Project no. 018525 REMOVALS Reduction_ modification and by dfgh4bnmu

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									                                         Project no. 018525

                                            REMOVALS

                       Reduction, modification and valorisation of sludge


Instrument: Specific Targeted Research Or Innovation Project

Thematic Priority: Global change and ecosystems, 1.1.6.3




                                      Periodic Activity Report




Period covered: from 1 July 2007 to 30 June 2008
Date of preparation: 15 October 2008
Start date of project: 1 July 2006
Duration: 3 years
Project coordinator name: Dr. Azael Fabregat Llangostera
Project coordinator organisation name: Universitat Rovira I Virgili
Revision: 1
REMOVALS, FP6-018525                                                           Periodic Activity Report


                                                                                                        Page
INDEX.                                                                                                    2
PUBLISHABLE EXECUTIVE SUMMARY.                                                                            3
Section 1 – Project objectives and major achievements during the reporting period.                        9
      1. Overview of general project objectives.                                                          9
      2. Summary of recommendations from previous reviews.                                               16
      3. Summary of the objectives for the reporting period, work performed, contractors involved and    17
      the main achievements in the period.
      4. If applicable, comment on the most important problems during the period including the           29
      corrective actions undertaken.
Section 2 – Workpackage progress of the period.                                                          34
Section 3 – Consortium management.                                                                       68
      1. Consortium management tasks and their achievement; problems which have occurred and             68
      how they were solved.
      2. Contractors: Comments regarding contributions, changes in responsibilities and changes to       68
      consortium itself, if any.
      3. Project timetable and status, including an updated, frontlined barchart. Clarify changes and    68
      impact on the planned milestones, if any.
      Table 5: Workpackages - Plan and Status Barchart.                                                  71
      4. Short comments and information on co-ordination activities                                      72
Section 4 – Other issues.                                                                                74
Annex – Plan for using and disseminating the knowledge.                                                  75
      Section 1 - Exploitable knowledge and its Use.                                                     75
      Section 2 – Dissemination of knowledge.                                                            77
      Section 3 - Publishable results.                                                                   82




2nd reporting period                                   2
REMOVALS, FP6-018525                                                              Periodic Activity Report


                                  Publishable executive summary

              Specific Targeted Research Or Innovation Project, FP6-018525

             REMOVALS: Reduction, modification and valorisation of sludge

                                      1 July 2006 - 30 June 2009
The overall objective of this project is to develop a technological policy that permits the reduction or the
modification or the valorisation of excess sludge. This policy should be applicable and implemented by every
municipal wastewater treatment plant. The project aims at developing strategies for the safe disposal and
reuse of waste sludge. The scope envisages developing several processes for reducing both amount and
toxicity of sludge, with simultaneous transformation into green energy vectors such as methane or hydrogen.
Also, valuable materials will be obtained from sludge, such as activated carbons, which will serve to gas
decontamination, water purification and in advanced oxidation processes, which could open new applications
for that waste, thus valorising it.
Activated sludge is the most popular biochemical process for municipal and industrial wastewater treatment.
However, a great amount of excess sludge (ES) resulting from activated sludge processes in wastewater
plants is becoming a serious issue, especially in industrial countries. In addition, this huge amount is
expected to yearly increase entailing a lack of final disposal lands and punishing the accomplishment of strict
regulations on environmental protection. New processes with introduction of ES digestion by ozonation and
thermophilic microbial digestion have been proved to be useful in reducing ES production in activated sludge
by recycling the treated ES into the aeration tank. These methods aim at reducing the ES formation and
have the main disadvantage of the potential accumulation of nonbiodegradable components in the effluents.
Considering the vast amount of ES and its variety, the development of other alternative ES-reuse
technologies is still required as the unfavourable economic impact must be minimised.
The ES reduction can be achieved by two different ways. On one hand, modification/optimisation of the
operation parameters for the classical sludge stabilisation processes can result in a better management and
a reduction of the treated sludge with a higher associated production of methane or even hydrogen.
Simultaneously, the toxicity can be reduced to meet the sanitary regulations before sludge disposal. On the
other hand, new uses of sludge are foreseen, e.g. the production of activated carbons and the recovery of
organic acids or valuable enzymes, which will be subsequently used in other applications. For instance, the
activated will be tested for wet oxidation with a trickle bed reactor using the activated carbon as oxidation
promoter, biofilters for liquid and gaseous organic contaminant removal where the fixed bed is activated
carbon, classical adsorption processes and finally enzymatic removal with a torus reactor. All these
treatment modules could be used directly by industries as novel one-step processes or previous specifically
targeted treatments before other classical techniques.
About the reduction and stabilisation of the excess and toxicity of sludges in anaerobic conditions, during the
second reporting period, at the same time the three anaerobic reactors have been maintained, one at
mesophilic conditions of 33ºC and two at the themophilic temperatures of 50ºC and 55ºC. Within this period
more conditions have been studied to complete the previous task, like changes in HRT and combination
between mesophilic-thermophilic reactors. More over a fourth reactor has been started up at 55ºC in order to
produce our own innoculum for methanogenic tests measurement over the pretreatments. Thermal pre-
treatments have been conducted in two different temperature ranges: 30 80ºC and 110ºC 200ºC. The
distinction is made due to the different equipment used in each case: glass reactor and autoclave,
respectively. Thermal pre-treatments yield a considerable increase of the soluble COD, which should
favourably impact the sludge transformation in the subsequent thermophilic digestion. As expected, the
temperature has a key role, and growing solubilisation has been found as temperature increases. However,
practically no organic matter removal has been observed, except for the higher temperatures and at low
extent. One hour pre-treatment seems to be enough to yield most of the solubilisation. Hydrogen peroxide
addition also results in an improvement of the soluble fraction. In this sense, probably low doses of peroxide
are desired as high doses requires much more time to be consumed with no equivalent impact on the
soluble fraction. In addition, high doses also yield direct organic matter elimination and increase the sludge
volume, both undesirable. Temperature has only some additional impact.
Concerning to the sludge stabilisation in autothermal conditions, the aerobic innoculum for the autothermal
pilot plant was provided by the Reus Wastewater Treatment plant, however the innoculum was taken at
mesophilic temperature of 30ºC. Therefore, it has been necessary to slowly acclimate these microorganisms


2nd reporting period                                  3
REMOVALS, FP6-018525                                                                  Periodic Activity Report


into thermophilic ranges. The strategy followed to acclimate the bacteria was to increase the temperature in
intervals of 5ºC, starting from 30ºC, every two weeks. The feed was made intermittently, once a day. The
plant has been operated for 80 days, without apparently troubles. Nevertheless, at present acclimate
bacteria have not been yet obtained. In the work focused on investigations about the mixing and aeration
performances of the ATAD reactor, a simplification of the system (phenomena decoupling) was firstly
required to be able to study both hydrodynamics and gas-liquid mass transfer. Coupled with the rheological
studies, this new experimental device will enable, in the next months, the agitation device (power number)
and the global hydrodynamics behaviour (flow regime, mixing time, kLa) to be characterised. This will
constitute the basis necessary to initiate the numerical modelling of the reactor.
Regarding the production of hydrogen from sludge, sewage biosolid pre-treatments for improving
fermentative hydrogen production have been evaluated and enzymatic saccharification identified as the most
effective. Enhancing hydrogen removal via addition of nitrogen gas into the bio-reactor headspace or
contents was evaluated and found to be effective at prolonging hydrogen production in the bio-reactor.
Hydrogen production can currently be sustained for a period of 6 hydraulic retention times (HRTs).
In relation to the utilisation of enzymes from sludge to optimise activated sludge digestion, the extraction of
enzymes was carried out in a first stage using activated sludge from WWTP Prague, and in a second stage
using sludge from WWTP Reus. The extraction was performed using three different methods: ultrasound,
mechanical, and magnetic stirring disintegration, adding different compounds to improve the recovery of
enzymes. The enzymes extracted and tested were protease and lipase. Between the compounds added to
improve the extraction, the presence of a non ionic detergent (Triton X-100) had the major influence for the
extraction. It seems that the addition of a cation exchange resin and the presence of buffer have not
significant effect in the extraction. About the feasibility of the enzymatic reactions in a torus reactor, in a first
step, the enzymatic elimination of phenol was experimentally studied in the torus reactor. In order to
compare the performances, several assays were also carried out with a stirred reactor. A high degree of
conversion was obtained for the enzymatic elimination of phenol in both reactors with the tested quantities of
phenol. It was concluded that, keeping a ratio of 1:1 between the phenol and the H2O2 initial molar quantities,
the highest final reaction conversion was obtained. Using the torus reactor was obtained 97% of phenol
conversion when the optimal concentrations of substrates were used. Also, a substrate inhibition was
presented in the reaction, this occurred when the H2O2 initial concentration was increased, and thus, the final
reaction conversion was lower. The excess of hydrogen peroxide in the mixture inhibited the catalytic activity
of the enzyme through the conversion of the peroxidase to inactive forms. A kinetic model based on
Michaelis-Menten with inhibition was proposed in order to have a unique kinetic model to be applied for any
initial phenol concentration. A good fitting was obtained with the proposed model for all the studied phenol
concentrations. In this way, a model that included the effect of the H2O2 and the phenol initial concentrations
and inhibitions was reached. The initial reaction rates were very similar in both reactors; however, better
phenol conversions were obtained in the torus reactor for all cases. In order to improve economically the
process, the enzyme should be used in a continuous regime over a long time period to exploit it completely.
For this reason it was necessary to immobilise the enzyme. Three different approaches for the covalent
immobilisation of the HRP were explored, concluding that, the periodate-mediated covalent immobilisation of
the HRP on Eupergit was found to be an effective method for the preparation of stable biocatalysts. In this
case, a maximum value of the immobilised enzyme activity of 126 U•g-1 was found using an enzyme loading
on the support of 17.6 mg•g-1. The activity of the immobilised enzyme was lower than the activity of the free
enzyme. However, a high degree of phenol conversion was obtained using less concentration of enzyme.
For the coupling of the enzymatic reaction with the numerical prediction of hydrodynamics and the validation
by comparison to experimental measurements. The enzymatic reaction of phenol with the HRP was
modelled using the CFD coupled to the kinetic model of the enzymatic reaction to the flow simulation. Then,
the reaction mechanism has to be defined to simulate the enzymatic reaction. For this, two different
strategies were studied. In the first one, while the enzyme concentration was kept small, only two reactions
were taken into consideration and no inhibition of the enzyme was analysed. The second strategy was
studied because inhibition of the reaction was found for some initial concentrations of the reagents. The next
step was the definition of the reaction rate in Fluent by the utilisation of a user-defined function (UDF). To do
this, it was necessary to write a small program in C language and coupling it to Fluent using the UDF utility.
The reaction rate was defined in the UDF utility using the kinetic parameters obtained experimentally. After
that, a patch (assignation of an initial value to variables into different cells) was done for each initial
concentration of the reagents into the reactor. Finally, to simulate the enzymatic reaction, it was used the
kinetic model with inhibition by H2O2 and taking into account the influence of the phenol initial concentration.
A very good agreement was obtained between experimental data and the CFD numerical simulations in
terms of phenol conversion, initial reaction rates and kinetic comparison. These results allowed the
possibility of optimising and scaling-up the process using the CFD modelisation.



2nd reporting period                                     4
REMOVALS, FP6-018525                                                                Periodic Activity Report


With reference to the gasification of sewage sludge, a full characterisation (including elemental analysis, TG
profiles, proximate analysis, composition of products from thermal decomposition) of three additional
samples of sewage sludge (two from Poland and one from Prague) were done. On the other hand, the study
performed on the influence of the pyrolysis extent on gasification process was extended. By the effect of
catalytic additives (dolomite, calcium oxide) on tar yield and gas phase composition Carbon dioxide and
oxygen under no isothermal conditions were employed to collect experimental data to establish the effect of
oxidizer on thermogravimetric and gas evolution profiles. Finally, the ASTM E 698 method was used for
preliminary fitting of experimental data for pyrolysis and CO2 gasification obtained at no isothermal
conditions.
Regarding to the production of organic substrate from sludge for enhancement of nutrient removal, the
optimal conditions for organic substrate production using different methods were found. It was confirmed that
quantity and quality of substrate produced by sludge fermentation can be controlled by choice of sludge type,
by sludge pre-treatment (disintegration for example) and by conditions of fermentation. The optimal types of
sludge or conditions of fermentation according to the evaluated criterion are:

    Benchmark                       Type of sludge             Temperature range                  Time
    COD production                  excess activated                 thermophilic          > 5 days (> 2 days**)
    COD/N ratio                         primary                   psychrophilic                  < 1 day
  DNR                       not significant difference               mesophilic                  < 2 days
*for mesophilic and **thermophilic temperature
The quality of produced substrate is higher than that of ethanol based on the denitrification test. The
recommendations concerning the optimal disintegration method based on the evaluated criteria are indicated
in the following table:

    Benchmark                                                Method of disintegration
    COD production                                           thermal
    COD/N ratio                                              thermal
    DNR                                                      thermal, freeze and thaw
    Energy consumption                                       mechanical, freeze and thaw

Performing batch kinetic tests of denitrification and phosphorus release with substrate produced from sludge,
the enhancement of processes was confirmed. It was found that that the extent of enhancement is
comparable with external substrate addition. The methods chosen for further continuous long term
experiments were mechanical, thermochemical and ultrasound disintegration. The main achievements of the
period are following: The highest phosphorus release rate was measured with mechanically disintegrated
activated sludge used as a source of organic matter. According the actual results, the organic substrate
released by mechanical disintegration can be successfully used as a substrate for denitrification. The system
can also efficiently nitrify the surplus ammonia nitrogen coming into the system with the substrate produced
from sludge. The efficiency of nitrogen and phosphorus removal improved in comparison to the control
model reactor. A longer period of operation is necessary for the evaluation of thermal disintegration and
disintegration of activated sludge by ultrasound, because change of activated sludge characteristics seems
to be bigger and long-term disintegration can have deteriorating effect on the sludge. Finally, experimental
work was focused on the operation of lab scale sequencing batch reactors treating municipal wastewater
enriched by nitrogen to achieve low COD/N ratio. Objective of the work was the evaluation of other
consequences related to use of organic substrate for enhancement of nutrient removal. It was found that
using the disintegration methods more benefits can be gained:
•         The improvement of denitrification and phosphorus release which contribute to improvement of N and
          P removal efficiency.
•         The minimization of surplus activated sludge production.
•         The deterioration of filamentous structure of sludge flocks which can improve the separation of
          activated sludge.
On advanced technology for the biological nitrogen removal of the reject water from the sludge dewatering
systems, during the second year of the REMOVALS project, two main objectives were achieved in this task.



2nd reporting period                                     5
REMOVALS, FP6-018525                                                                  Periodic Activity Report


Firstly, it was successfully carried out the start-up of a nitrifying activated sludge three-reactor system with
100% of partial nitrification directly from the sludge of a municipal WWTP. The applied control strategy is a PI
controller that controls the nitrogen loading rate (NLR) of the system with on-line measurements of the
oxygen uptake rate (OUR) in the reactors. Secondly, it was confirmed the stability of the partial nitrification
process in the long term operation (more than 6 months). On the other hand, about the evaluation of an airlift
reactor for nitritation using activated carbon (AC) as biocarrier for the advanced technology, three main
objectives were achieved. Firstly, it was finalised the set-up of the nitrifying airlift pilot plant with the
purchasing of the instrumentation and control devices and the implementation and programming of the
control and monitoring software. Secondly, it was carried out the start-up of the nitrifying airlift pilot plant with
activated carbon provided by Chemviron Carbon Limited. The main achievement of this start-up was the
development of a system with high partial nitrifying capacity and a hybrid distribution of the biomass:
granular biomass (73%) and biofilm over AC (27%). Finally, adsorption tests of ammonium, nitrite and nitrate
were performed with the AC provided by Chemviron Carbon Limited in parallel with the operation of the pilot
plant.
On the topic of the minimisation of sludge production by utilisation of biological potential in membrane
bioreactors, Both bench-scale plants were operated for 200 days at a very high sludge age of 148 d with a
hydraulic retention time of 10 h. Afterwards the hydraulic retention time of one bench-scale plant was
reduced to 5h and the influence on sludge characteristics was monitored. Further changes in operating
conditions are planed. Sludge characteristics, like filterability, dewaterability, oxygen transfer and viscosity
have a strong impact on operational and sludge disposal costs. During the operation of both plants, sludge
samples were taken once a week from the aeration tank of both plants and were analysed immediately for
total and volatile suspended solids (MLSS, VSS) concentration, dewaterability (CST), filterability (TTF),
rheology and oxygen transfer coefficient (kLa). For the identification of suitable sludge treatment methods we
have done some screening tests with a test unit supplied by Salsnes Filter AS to see whether their Salsnes
Filter is useful for sludge thickening. These tests were already done and the evaluation of the results is still in
progress.
About the destruction of organic compounds in sewage sludge suspensions by ultrasound and catalytic wet
air oxidation, the combination of ultrasonication (which should ensure the breaking of insoluble
macromolecules in the solid phase of the sludge and favour their solubilisation in the liquid phase) and of
catalytic wet air oxidation in the presence of heterogeneous catalysts (the higher solubilisation of the solid
organic matter should prevent the catalysts from deactivation by deposition of solid organic matter) was
investigated. The influence of different parameters of the ultrasonic treatment was investigated on the sludge
solution. The observed effects were: a strong particle size reduction (from 274 to 4.5 μm for industrial
sludge), an increase of the COD in liquid phase (up to 1 200 mg/L), as well as the increase of TOC (up to
600 mg/L) and protein content in the liquid phase. Ultrasound power and sonication time have similar
positive effects: for a maximum effect, a power of 200 W during 60 min is necessary. There is an optimum
concentration of sludge of 12 g/L (of dry solid) for municipal sludge. It was also found that it is better to
operate without temperature control. The combination of sonication (which should ensure the breaking of
insoluble macromolecules in the solid phase of the sludge and favour their solubilisation in the liquid phase)
and of catalytic wet air oxidation in the presence of heterogeneous catalysts (the higher solubilisation of the
solid organic matter should prevent the catalysts from deactivation by deposition of solid organic matter).
Different Pt and Ru catalysts were prepared on oxide supports (TiO2, ZrO2 and CeO2) which were tested in a
batch reactor in the WAO of three different sludges (one municipal sludge, two industrial sludges) with an
initial TOC content of ca. 3 g/L. The temperature was 190°C, the partial pressure of air 37 bar. The effect of
a sonication pre-treatment was examined, by analysing the TOC content of the residual organic solid and the
TOC content in the oxidized liquor, as well as the global TOC abatement in the sludge suspensions. The
sonication pre-treatment, was not effective enough in the solubilisation of the suspended matter. As a result
of the disintegration by the ultrasounds, the organic solid is in a more finely divided state which favours even
more its adsorption on the surface presented by the solid catalyst. The beneficial effect of partial
solubilisation is annealed and the global TOC conversion is not significantly improved. This was confirmed
by performing similar experiments using mechanical disintegration by an ultra-Turrax as a pre-treatment
method. On the other hand, a thermal pre-treatment of the sludge at 200°C and then a catalytic WAO on the
supernatant liquor clearly demonstrated the positive effect of the addition of the solid catalysts prepared.
On the subject of the production of activated carbon from sludge, The response to steam activation of the
DRAW sludge was modelled using the response surface methodology (RSM) technique. The RSM model
was subsequently used to determine the optimum conditions for activating dewatered, raw (DRAW) sludge -
in the 1-12 month period, the response to steam activation of dewatered, mesophilically, anaerobically
digested (DMAD) sludge had been modelled by means of the RSM technique. The DRAW sludge was found
to be a better feedstock for the production of SBAs with relatively high BET surface areas. The optimum


2nd reporting period                                     6
REMOVALS, FP6-018525                                                               Periodic Activity Report


steam activation conditions determined from the RSM work was subsequently applied to French and Polish
sludges supplied by P2 GPA and P9 TUL respectively. The BET surface area results suggested that
aerobically digested and raw sludges represented the best feedstock for the production of activated carbons.
A range of new chemical activation reagents were evaluated, as was the response of dried and untreated
sewage sludge (as opposed to the previously investigated carbonised sludge) to chemical activation.
Untreated sewage sludge was ascertained to be an effective feedstock. The best activator was observed to
be K2CO3; BET surface areas approaching 1900 m2/g were achieved with this reagent. SBA have been
characterised in terms of their phenol uptake, catalytic activity (peroxide number), CCl4 uptake, mineralogy
(by XRD analysis), ball pan hardness, pH and their surface chemistry (by FTIR analysis). On the other hand,
hardened carbons were produced and it was ascertained that SBAs possessing the requisite catalytic
properties could be produced by the selection of the appropriate sludge type (DRAW) and activation method
(steam activation under the optimum conditions calculated from the RSM work).
Concerning to the utilisation of activated carbon as catalyst in wet air oxidation, wet air oxidation of aqueous
phenol solutions will be conducted both in a batch slurry reactor and a laboratory scale packed bed reactor
operating in trickle flow regime. Conditions of temperature (120-160ºC), oxygen partial pressure (2-8 bar) will
be studied and commercial and sludge based activated carbons produced in WP11 will be tested as catalytic
material. The main achievements were, firstly, the screening of 15 different carbons (commercial and sludge
based) was terminated in batch slurry reactors showing that the less economically attractive K2CO3 activated
and water or acid washed DMAD carbons are the most active ones. As alternatives, a steam activated
DMAD and a hardened steam activated DRAW carbon were selected as candidates for continuous TBR
tests. Secondly, TBR runs with the afore mentioned carbons gave acceptable conversions of phenol and
TOC at 140-160ºC and 4 bar of oxygen partial pressure compared to the commercial carbons, but the former
were not enough stable over time on stream. Finally, the problematic of important metal leaching of the
sludge based carbons due to their high ash contents could be highlighted as a secondary pollution and more
studies are necessary to address the issues of stability and metal leaching of sludge based carbons.
Different operating conditions such as reaction temperature (120-160ºC) and oxygen partial pressure (up to
4 bar) should be evaluated either in batch or continuous runs to obtain suitable concentration reaction/space
time profiles. The experimental data would be then adjusted with a lumped kinetic model, namely the
Generalized Kinetic Model, which considers three types of compounds: easier degraded reactants;
intermediates with difficult degradation and desired end products. Trickle-bed reactor CFD model was
upgraded in order to provide a more universal multiphase scale approach either in terms of hydrodynamic or
reaction parameters. Euler-Euler k-fluid and Volume-of-Fluid (VOF) models were developed to provide a
behavior analysis in transient conditions. The computational flow modeling techniques predicted successfully
gas-liquid distribution and pressure gradient, mainly with Eulerian codes. Local temperature variation and
Total Organic Carbon (TOC) profiles were evaluated axial and radially providing a more rigorous physical
description of the underlying flow process. Computational runs exhibited backmixing phenomena, poor radial
mixing and revealed the existence of hot spots in the simulated flow regime.
In relation to the utilisation of activated carbon as catalyst in AD-OX process, some SBAC, Steam Activate
Dewatered Raw, has convenient adsorption capacity, despite law surface area. All Sludge Based Activated
carbons have been tested as catalysts to oxidize phenol. Only first oxidation has been checked. For
comparison or exploration work on commercial AC has been extended to pharmaceuticals, and other
pollutants, especially real effluents containing salts. The complete modelling of AD-OX process operated in
our conditions is not feasible due to non isothermal conditions. Nevertheless a simplified model will be built
up. The adsorption step is now conveniently represented even in the case of mixture of pollutants.
Breakthrough curves are well simulated. A mini automated pilot plant has been built up and validated on AD-
OX process. It has been used first with commercial AC then with SBAC Steam Activate Dewatered Raw and
with several model pollutants and real wastewater. This SBAC being selected for its adsorption and oxidation
characteristics was found not strong enough. The hardened one- using PVA as a binder resulted in important
foaming avoiding its use in pressurized fixed bed. The reactor material stainless steel is not resistant to the
synergetic corrosion faced when using chlorides and carbon. It had to be changed 5 times, a new material
able to undergo such corroding system is not yet available and salted effluent are no longer used.
Nevertheless the feasibility of AD-OX on SBAC and salted effluents is a major achievement due to its
industrial importance.
About the utilisation of activated carbon in adsorption processes, optimal contact times were determined for
2 organic compounds (phenol and potassium hydrogenophtalate) in batch tests. Performances comparison
with a commercial activated carbon vas realised. On the other hand, optimal contact times and adsorption
capacities were determined for 3 dyes (AR18, BB9, BV4) and 2 metal ions (Ni, Cu) and one metalloid (As) in
batch tests.




2nd reporting period                                   7
REMOVALS, FP6-018525                                                               Periodic Activity Report


As regards of the use of activated carbon in biofilters for elimination of industrial waste gases, The evaluation
of physical-chemical characteristics of organic, inorganic and sludge-based packing materials as well as the
efficiency of biofilters packed with sludge-based carbons was carried out. A biofiltration model was
developed, calibrated and validated for toluene removal in biofilters. The proper description of a fungal
biofilter degrading toluene by means of a model based on mass balances for the gas and biofilm phases was
realised. Physical-chemical parameters of the model as well as biological activity parameters where
determined. Also, the influence of main processes and parameters was determined.




2nd reporting period                                   8
REMOVALS, FP6-018525                                                               Periodic Activity Report


Section 1 – Project objectives and major achievements during the reporting period.


1. Overview of general project objectives.
The overall objective of this project is to develop a technological policy to allow either the reduction, the
modification or the valorisation of excess sludge. This policy should be applicable and implemented by any
municipal wastewater treatment plant.
The proposal aims at developing strategies for the safe disposal and reuse of waste sludge. The scope
envisages developing several processes for reducing both amount and toxicity of sludge, with simultaneous
transformation into green energy vectors such as methane or hydrogen. Also, valuable materials will be
obtained from sludge, such as activated carbons, which will serve to gas decontamination, water purification
and in advanced oxidation processes, which could open new applications for that waste, thus valorising it.
Activated sludge-based depuration is the most popular biochemical process for municipal and industrial
wastewater treatment. However, a great amount of excess sludge (ES) resulting from activated sludge
processes in wastewater plants is becoming a serious issue, especially in industrial countries. In addition,
this huge amount is expected to yearly increase entailing a lack of final disposal lands and punishing the
accomplishment of strict regulations on environmental protection. New processes with introduction of ES
digestion by ozonation and thermophilic microbial digestion have been proved to be useful in reducing ES
production in activated sludge by recycling the treated ES into the aeration tank. These methods aim at
reducing the ES formation and have the main disadvantage of the potential accumulation of
nonbiodegradable components in the effluents. Considering the vast amount of ES and its variety, the
development of other alternative ES-reuse technologies is still required as the unfavourable economic impact
must be minimised.
The ES reduction can be achieved by two different ways. On one hand, modification/optimisation of the
operation parameters for the classical sludge stabilisation processes can result in a better management and
a reduction of the treated sludge with a higher associated production of methane or even hydrogen.
Simultaneously, the toxicity can be reduced to meet the sanitary regulations before sludge disposal. On the
other hand, new uses of sludge are foreseen, e.g. the production of activated carbons and the recovery of
organic acids or valuable enzymes, which subsequently will be used in other applications. For instance, the
activated will be tested for wet oxidation with a trickle bed reactor using the activated carbon as oxidation
promoter, biofilters for liquid and gaseous organic contaminant removal where the fixed bed is activated
carbon, classical adsorption processes and finally enzymatic removal with a torus reactor. All these
treatment modules could be used directly by industries as novel one-step processes or previous specifically
targeted treatments before other classical techniques.


1.1.     Optimisation of the operation parameters for the classical sludge processes.
1.1.1.     Reduction and stabilisation of the excess and toxicity of sludges in anaerobic conditions in
           combination with enhancing biodegradability sludge preteatments.
The expanding construction of sewage plants for the biological treatment of urban and industrial effluents is
generating a growing amount of sludge. For instance, only in UK –one of the countries participating and the
present proposal- the amount of sludge is predicted to be above 2.000.000 tonnes by 2006. The need for
optimised processes of treating and processing this vast amount of waste sludge is thus easily foreseen. In
addition, the European Directive on the use of sewage sludge on agricultural land is currently under review
and more stringent specifications regarding the presence of pathogens are expected. Therefore, a deep
examination of the present stabilisation treatments of sludge, which must lead to innovative processes, is
required to face the near future needs. At present, mesophilic processes (under 35ºC) predominate but they
show to be unable to accomplish the new sanitary specifications. Consequently, only the migration to higher
temperature conditions, i.e. thermophilic operation, seems to be capable of producing stabilised sludge that
meets the regulations for the presence of bacteria. Thermophilic digestion is conducted in anaerobic
conditions over a 40-70ºC range. The main advantages of thermophilic over mesophilic treatments are
greater degradation rates, higher loading rates, removal of pathogens, and lower sludge yield. Only the poor
settling of the sludge effluent, which difficulties the separation of the solid fraction, can be noted as
disadvantage. Although some research has been done on this topic, there is a clear lack of information about
the treatment efficiency owing to the influence of the origin of the sludge and seasonal effect. This limits the
applicability of the present knowledge and is preventing thermophilic processes from being more rapidly
implemented. In addition, few information is available on the beneficial effect of enhancing biodegradability


2nd reporting period                                   9
REMOVALS, FP6-018525                                                               Periodic Activity Report


pretreatments, either mechanical or chemical, that could improve the thermophilic performance thus reducing
the specific cost.


1.1.2.   Sludge stabilisation in autothermal conditions.
Obviously, higher temperature requirement for the thermophilic treatments also is a drawback since external
heat must be provided in order to achieve thermophilic conditions. The exceeding energy coming from
cogeneration systems fed by the methane generated in-situ can easily offset this point. However, this is an
indirect process with limited heat efficiency. Although the first study focused on Autothermal Thermophilic
Aerobic is from decades ago, ATAD is in fact a technology relatively new. Its main characteristic is that the
reaction itself occurring in an aerobic environment produces the most of the energy required to achieve the
thermophilic conditions. This is possible because of the high load of organic matter to be degraded, which
generates a high heat power per volume unit. As counterpart, there is a greater need of dissolved oxygen
that only can be met using tailored equipment or pure oxygen. However, in case of difficult energy
availability, this could be a very suitable solution to allow the implementation of thermophilic processes, e.g.
when cogeneration plants are not recommended.


1.1.3.   Production of hydrogen from sludge.
In the near future hydrogen will help the E.U. address issues of security of energy supply, environmental
impact and climate change, and decentralised energy production. To achieve this, hydrogen must be
produced sustainably and not as at present from fossil fuels. Hydrogen can be produced from biomass such
as sewage sludge by physico-chemical technologies such as gasification and pyrolysis, or by reforming
methane produced by anaerobic digestion. Hydrogen can also be produced from sewage sludge by a novel
fermentation process, resembling the acidification stage of anaerobic digestion. Generally biological
processes such as fermentation are considered more environmentally friendly and less energy-intensive
than physico-chemical processes. Each of the above processes is CO2 neutral, as CO2 released is part of
the natural carbon cycle. Sewage sludge may be over 50% carbohydrate, mainly cellulose and hemi-
cellulose, which can be fermented to yield H2 and CO2 in almost equal quantities, together with organic
fermentation end products. The fermentation process, which is similar to the acidogenic stage used to
improve anaerobic digestibility of sludge, has not been optimised for H2 production. The applicants have
experience in optimising the fermentation of biomass such as wheat starch and sugar beet to H2 using
sewage sludge as starter culture. The main objective is to investigate operating conditions for fermentation
giving maximal yields of H2 from sewage sludge and the technical and economic feasibility of this process.


1.1.4.   Advanced technology for the biological nitrogen removal of the reject water from the sludge
         dewatering systems.
New legislation for nitrogen removal requires optimisation of existing WWTPs. Conventional biological
extension of these WWTPs requires additional volume for aeration tanks and consequently a substantial
investment. In order to avoid unnecessary capital expenditure and minimise investment costs, it has been
shown to be more advantageous in many cases to increase nutrient removal capacity by making optimal use
of the existing process units and by implementing complementary techniques. A promising complementary
technique option for WWTPs with sludge digestion is the treatment of the liquor from sludge dewatering and
sludge drying. This internal process stream, called reject water, contains up to 20-25% of the total influent
nitrogen, but contributes only a minor 2% of the total influent flow. Normally, the reject water is recycled to
the activated sludge reactors but some studies in the Netherlands and Germany have shown that the
separated treatment of the reject water might be more economical compared to conventional extension of
the WWTPs. One of the most interesting technologies for the reject water treatment is the biological nitrogen
removal (BNR) via nitrite that consists of the ammonium oxidation to nitrite (partial nitrification) followed by
the denitrification from nitrite to nitrogen gas. This technology could suppose a 25% reduction of the total
oxygen requirements as well as a reduction in the amount of sludge produced compared with the classical
BNR. Several strategies have been tested to achieve partial nitrification. The main difference among them is
how it is favoured the ammonium oxidation to nitrite in front of the oxidation to nitrate. One methodology is
based on decreasing the dissolved oxygen (DO) concentration. Other possible methodology is the SHARON
process, which works at high temperatures (30-35ºC), short hydraulic retention time (about 1 day) and
without sludge retention. Finally, the substrate inhibition of the nitrifying biomass can be applied to achieve
the partial nitrification. All of the above mentioned strategies could be applied in suspended biomass
systems (e.g. activated sludge reactors) or immobilised biomass systems (e.g. airlift reactors). The biomass


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REMOVALS, FP6-018525                                                               Periodic Activity Report


immobilisation in airlift reactors can be done using activated carbon (AC) as biocarrier, although its
application is possibly restricted by its expansive cost. The production of AC from sludge of WWTP can be
the starting-point for its wide application as biocarrier.


1.2.     Utilisation of innovative technologies to minimise the excess sludge production.
1.2.1.     Gasification of sewage sludge with enhanced gas production.
Gasification of sewage sludge is the most promising alternatives to traditional disposal routes for sewage
sludge. The pyrolysis and gasification of sludge have several advantages over traditional incineration for
example, the exhaust gas requires more basic cleaning than for incineration and the char produced is less
susceptible to the leaching of heavy metals. Gasification seems to be better technology because the product
gas is easier to use than the mixed gas/oil product from pyrolysis. Gasification involves the partial
combustion of sewage sludge to produce gaseous fuels or synthesis gas by heating in a gasification medium
such as air, carbon dioxide or steam. These gases have many applications such as generation of heat or
electricity, synthesis of liquid fuels, production of hydrogen, synthesis of chemicals and manufacturing of fuel
cells. At large scale the fuel gas produced from biomass gasification can be used in an integrated
gasification combined cycle (IGCC) power plant. The high thermal efficiency of the combined cycle means
that these plants have the potential to be economically competitive. However, no large scale trials with
sewage sludge have been reported. Economic analysis has shown that on cost alone, energy from biomass
is not able to compete with existing fossil fuel resources, at least in comparison with the low oil price
prevailing in the past years. However, this situation is rapidly reversing. Generally speaking, gasification
occurs in three stages, drying, pyrolysis (devolatilisation) and gasification of char. There are many studies on
the successful thermo-chemical treatment (drying, pyrolysis and gasification) of municipal sewage sludge,
however very few investigators reported the fundamentals of these systems. Our project aims to fill this gap.


1.2.2.     Minimisation of sludge production by utilisation of biological potential in membrane
           bioreactors.
In addition to the treatment of already existing sludge, the minimisation of sludge production by the utilisation
of its biological potential in membrane bioreactors is devoted to tackle the waste sludge problem at its source
by minimisation of sludge production through direct exploitation of the sludge. In wastewater treatment,
excess sludge disposal accounts for 30-60 % of the total processing costs. The use of maintenance
demands offers the possibility of decreased excess biomass formation. At low growth rates, microorganisms
utilise available substrates mainly for maintenance purposes. This effect is observed as lower sludge yield
YB/S at high sludge ages or at high biomass concentrations respectively. While this phenomenon is well-
known, its application to the common activated sludge process (ASP) is limited since the settling ability of
sludge decreases at concentrations beyond 5 gMLSS/L. Besides, due to the complex nature of real
wastewater, systematic investigations on the influence of operating parameters on the degree of excess
sludge minimisation are scarce. Only a deeper understanding of the prevailing phenomena will allow an
impartial ecological and economical assessment of the inherent potential. Thus, higher concentrations are
possible in membrane bioreactors (MBR), i.e. combinations of common bioreactors and membrane
separation units as a replacement for settling tanks. Due to the increased biomass concentration, smaller
footprint is also required. Commonly, micro- or ultrafiltration membranes (pore sizes approx. 0.01–0.4 µm)
are applied. Since membrane costs have decreased dramatically over the last years (to approx. 50 €/m²),
this has now become an economically feasible alternative to ASP with an increasing number of full scale
plants coming into operation. In order to achieve feasible oxygen transfer rates, MLSS concentrations of
existing MBR plants are limited to approx. 15 g l-1. The corresponding growth rates or sludge retention times
(SRT) are still outside the regions where excess sludge production would be effected significantly. One way
to utilise the maintenance demands for excess sludge minimisation is to adapt design and operating
parameters like reactor volume and hydraulic retention time such that sludge loading rate and thereby
growth rate become minute. While operating bigger plants at higher hydraulic retention times (HRT) would
initially lead to higher investment costs it might after all be more economical in terms of excess sludge
minimisation. While a significant reduction of excess sludge production is expected, the residual amount still
needs to be treated. As MBR sludge characteristics differ from ASP, the application of sludge treatment
methods has to be adapted. In ASP, flocs may reach several 100 µm in size. Hydrodynamic stress in MBRs
reduces floc size (to approx. 30–60 µm). High biomass concentrations give rise to non-Newtonian behaviour
with high apparent viscosities. Operating conditions such as sludge loading rate and higher shear stress in
MBRs affect the production of extracellular polymeric substances (EPS). All factors lead to a different



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REMOVALS, FP6-018525                                                              Periodic Activity Report


dewaterability behaviour and degree. Therefore, the treatment process most suited for MBR sludges should
be identified.


1.2.3.     Destruction of organic compounds in sewage sludge suspensions by ultrasound and
           catalytic wet air oxidation.
Municipal and industrial wastewater treatment plants produce large volumes of sludge, and their processing
and disposal is by far the most complex problem in the field of wastewater treatment. Wet Air Oxidation (or
thermal liquid-phase oxidation process) has a great potential for the treatment of effluents containing a high
content of organic matter (COD Chemical Oxygen demand 10-100 g/l) or toxic pollutants for which direct
biological purification is not possible. Generally, this process takes place at severe reaction temperatures
(200-320°C) and pressures (20-200 bar). In a typical WAO system, waste is pumped through a heat
exchanger into a reactor along with compressed air. The high temperature and pressure in the reactor
maintains water in the liquid state and increases the solubility of oxygen. The organic contaminants
dissolved in water are either degraded to smaller intermediates or mineralised into CO2 and H2O, ammonia
or nitrogen, and inorganic salts. This process can be used to decontaminate a wide variety of industrial
waste streams, such as those generated from pulp and paper mills, breweries and chemical processing
plants. One of the major uses of WAO is for the treatment of residual sludge from biological treatment plants,
where the sludge is either completely oxidised or rendered suitable for disposal or biological treatment. ca. a
hundred WAO plants are in operation over world. Through the use of appropriate catalysts, the severity of
the processing conditions can be reduced to improve the economics of the operation, in addition to the
improvement for the further digestion steps.


1.2.4.     Excess sludge reduction by dewaterability.
Sludge treatments are based on processing the waste activated sludge (WAS) from the biological stage in
an aerobic digester. In a lot of processes, aerobically digested sludge is sent to drying beds, before disposal
off-site. The final clarifier effluent can be discharged after chlorination and/or UV disinfection. Due to the
increasing influent loads to the system, the whole process could be overloaded and needs to be redesigned.
Big amounts of wet sludge going to drying beds and final deposit are costly for the operation of the plant. In
these cases, biological processes also show instabilities, endangering the possibilities to maintain the
required effluent quality. This objective is dedicated to explore the possibilities to reduce the amount of
sludge by sending biological and/or chemical activated (secondary) sludge in a loop back to the Salsnes
Clarifier and mix the secondary sludge with raw sewage to see how much secondary sludge it is possible to
mix with the raw sewage and still be able to dewater with the integrated dewatering unit. This kind of design
has to be investigated in order to achieve a possible reduction of the WAS at this particular WWTP from
        3                                     3
15,0 m /day with 1-2% dry matter to 1,3 m /day of dewatered sludge with approx 20-25% dry matter. The
upgrading of existent wastewater treatment plants will assure a decrease of operation costs by the reduction
of the load on the biological process. On the other hand, utilisation of obsolete devices can reduce the cost
of upgrading.


1.3.     Valorisation of excess sludge in beneficial products that can be used directly in sludge
         reduction or in other applications.
1.3.1.     Production of activated carbon from sludge.
The production of adsorbents from surplus sludge has received considerable attention since the early 70s.
Due to the high carbon content of sludge, the manufacturing procedures applied are equivalent to the
industrial practice for the production of activated carbon from more conventional materials, such as different
coal grades or wood. Activated carbons are produced by different routes: physical and chemical activation.
Physical activation is a two stage process including a pyrolysis or carbonisation stage followed by activation
with gas phase reagents such as steam or CO2. In chemical activation, the conversion of non-carbonised
raw materials into activated carbon proceeds under the action of dehydrating reagents at high temperatures.
Using sewage sludge as a raw material both routes have been tested although special interest has been
devoted to chemical activation due to the best performance of the resulting sludge-based adsorbents. The
research carried out until the moment has relayed on the use of H2SO4 and ZnCl2, although the latter is out
of consideration in the industrial practice for environmental reasons. The sludge-based adsorbents are
heterogeneous in nature, half organic, and half inorganic and do not match the quality of commercial
activated carbon in terms of surface area or pore size distribution. However they have been shown to



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REMOVALS, FP6-018525                                                              Periodic Activity Report


perform similarly for certain environmental applications, such as sulphurous compounds removal from waste
streams or the adsorption of high molecular weight compounds in liquid phase applications. In spite of the
work carried out until the moment, much remain to be done. In particular, there are other more
environmentally sound activating agents and widely applied in industrial processes, such as H3PO4, KOH,
NaHCO3 or Na2CO3, which have still not been investigated. Depending on the type of activator, the results
may differ considerably and confer to sludge-based adsorbents distinctive properties that render them more
suitable features for certain applications. In addition, to explore new applications as proposed in the
framework of this project may broaden the fields of application and make the proposal even more attractive.


1.3.2.     Utilisation of enzymes from sludge to optimise activated sludge digestion.
About 60-70% of organic matter contained by domestic wastewater is lipids and proteins. The accessibility of
this organic matter to microorganisms metabolism is only possible with enzymes in the media, so it is needed
to know the factors affecting the activity of enzymes and finally, what organisms produce these enzymes.
Some studies have demonstrated that these enzymes cannot be produced by standard cultivation
techniques, therefore, it is necessary to isolate them in order to test their activity. The extension of
exoenzyme activity present in activated sludge is negligible, this fact means that the enzymes are
immobilised on flocs. The enzymes are connected on the surface of cells or imbedded in the extracellular
polymeric substances (EPS). Well known extraction and disruption methods will be used to provide large
quantities of enzyme to be tested in torus reactor. Reactors of torus geometry have been studied since many
years ago. Those geometries have been found to be more interesting than classical stirred tanks in some
chemical engineering applications. It was observed that the loop configuration involves low pressure drop,
and thus reduces power consumption for a given mixing operation. Another advantage is the high dispersion
attained because of Dean vortices involved by the reactor bends, and of the use of a simple marine screw
impeller in the torus axis that generates an efficient three-dimensional swirling motion in the geometry. The
combination of these two effects leads to an absence of dead volumes in the reactor, which facilitates the
scaling-up of its performance. Residence time can be very accurately controlled, making torus reactors very
interesting for biochemical applications like enzymatic reactions, especially in continuous mode. Thus,
reagents can be precisely fed according to the needs of the chemical reaction kinetic. Moreover, the torus
geometry gives a very efficient mixing that enhances mass transfer, thus permitting to employ the overall
volume of the reactor.


1.3.3.     Production of organic substrate from sludge for enhancement of nutrient removal.
Another promising method of optimisation of existing WWTPs is improving of COD/N (COD:P) ratio in
biological reactor. The addition of external carbon source causes mostly unacceptable increase of operating
costs. Therefore an internal carbon source is needed. The disintegration methods were until now
successfully used for enhancement of anaerobic digestion of excess activated sludge. The use of such
techniques for production of degradable organic substrate to improve denitrification or phosphate uptake
seems to be very promising. Efficient nutrient (N,P) removal is today one of the most problematic tasks of
wastewater treatment. Biological methods of nutrient removal are very efficient and sustainable, however
lack of organic substrate in wastewater often limits the process efficiency. Addition of external carbon source
is possible but very expensive solution. Another possible way is to search for internal carbon source and
excess activated sludge can be one of them. The method of volatile fatty acids production from sludge by its
prefermentation is well known, but the process control is not solved satisfactorily. The new methods of
excess sludge disintegration and treatment will be studied. The aim of such sludge treatment is the
production of organic substrate suitable for nutrient removal and minimisation of surplus sludge production.
The disintegration of cell walls of sludge and production of cell lysate can even stimulate the activity of
different trophic group of microorganisms.


1.4.     Utilisation of valorised sludge products in processes for the detoxification of industrial
         wastewaters and wastegases.
1.4.1.     Utilisation of activated carbon as catalyst in wet air oxidation.
The Catalytic Wet Oxidation (CWO) emerges as a worldwide help process in reducing the toxicity of liquid
effluents when direct biological treatment is not feasible. CWO has been earning nowadays an important
industrial role in different chemical companies for the treatment of toxic effluents. Therefore, research in
environmental catalysis is of great importance regarding to CWO wastewater cleanup technology in order to



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REMOVALS, FP6-018525                                                               Periodic Activity Report


meet low operation costs even if compared with non-catalytic treatments. The use of precious metals makes
the process expensive and has been unwelcome in many cases for pollution control. Development of active,
stable and economical catalysts for the Wet Oxidation Process is therefore nowadays critical. The efficiency
of the CWO technology cannot be only limited to the conversion of certain compounds into other chemical
species such as low carboxylic acids, which are in many cases refractory compounds. Therefore, the
complete conversion of carbonyl compounds to carbon dioxide and water can be predicted more adequately
by lumped TOC concentration measurements that represent then the major proof of the high performance of
the process. Also lumped kinetic models have to be used in order to represent the reaction mechanisms
involved in the oxidation of complex mixtures of countless compounds often present in industrial effluents. In
this context, a new kinetic model was proposed involving different groups of pollutants, namely, those easy
to oxidise, those refractory to the oxidation process and those that are unable to be decomposed. In this
context, the main goal of the study will be focused on the use of activated carbons in the removal of
industrial wastewater by catalytic wet air oxidation, as an integrated approach on the global objective of the
present project addressing the recycle of municipal sludges into high value materials. Activated carbon has
demonstrated to have superior catalytic activity, even if compared with metal oxide catalysts. In order to
define the catalytic efficiency of these new materials, comparison with other catalysts will be performed.
These studies will be carried out in our laboratory in a stirred reactor unit for kinetic studies and analysis of
the catalytic performance as well as in a trickle-bed reactor (TBR) in order to achieve the behaviour of the
system at industrial conditions. Furthermore, a pilot plant will be installed in a waste treatment company in
order to evaluate the Catalytic Wet Oxidation process with industrial data. Moreover, simulation studies of
the TBR will be undertaken by conventional computational methods as well as through the use of the more
recent Computational Fluid Dynamic (CFD) techniques with the goal to assess the scale-up and optimisation
of CWAO systems.


1.4.2.   Utilisation of activated carbon as catalyst in AD-OX process.
The concept of sequential adsorption and catalytic oxidation (AD-OX) on the active carbon bed for
elimination of non biodegradable or toxic organic pollutants as a preliminary water treatment has been
patented in 2001 and presented at the 2nd International Symposium on multifunctional reactors Nurenberg.
It has been validated at the lab scale for phenol polluted water with commercial active carbon. Both the
adsorption step and the oxidative regeneration one have been investigated separately then successively to
select convenient operation conditions for each step. Many aspects are still to be worked out and specially
the behaviour of active carbon when undergoing many cycles, as some deactivation and consumption have
been suggested by previous studies concerned by WCAO on active carbons. The type of reactor and more
precisely the liquid fraction (hold up) in the reactor would have significant effect on side reaction and the
related deactivation by irreversible adsorption of heavy compounds of polyphenol type. Trickling flow seems
to be most appropriate for stabilised activity. With regards to ad-ox economy the optimised duration of each
step cycles has to be found, the regeneration ratio obtained by partial oxidation being the key parameter. For
an application of this process as a pretreatment of industrial toxic wastewaters only pollutants which could be
oxidised in non toxic byproducts are concerned. For this preliminary separated investigations on adsorption
and mainly on oxidative regeneration are to be performed. The activated carbon is well known as a universal
adsorbent to remove organic molecules present in air. The mechanisms of diffusion and transfer in the
porous volume are well stated. The kinetics and the adsorption capacities have been previously determined
for a large number of volatile compounds. Fixed beds are generally used in air treatment. Polluted air is
applied directly to one end and forced through the packing adsorbent by pressure. However, the saturation
of material requires a desorption of adsorbent which is carried out by, pressure swing systems and heating
with steam or hot gas. The characteristics of commercial activated carbons show high specific surface area
and weak micropore distribution. These activated carbons are used both for drinking water or wastewater.
Then, the cost induced for wastewater treatments is important. Such high quality porous carbons are not
required for industrial wastewaters. It would be interesting to carry out a lower quality activated carbon to
these kinds of polluted effluents. Activated carbons produced from wastewater treatment plant sludge
(WWPS) seems to be promising and useful materials in term of cost. However, studies for use of WWPS
activated carbons are required to determine their performances to remove organics, inorganics or heavy
metal ions. To get better performances and a longer lifetime of biological filters for waste gas treatment, it is
possible to use the activated carbon both as porous media and bacteria support. In this case the porous
carbon is a storage of recalcitrant pollutant and also a support of bacteria degrading biodegradable
compounds. But, due to moisture required for biological life and the presence of bacteria, the mechanisms of
pollutant elimination are more complex in terms of diffusion and molecule adsorption. Then, a study has to
be performed to a better understanding of physical and biological phenomena. Thus, some specific operating
conditions have to be determined to define the best humidity level, and the optimal volumetric load to apply


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REMOVALS, FP6-018525                                                               Periodic Activity Report


to the biofilter. This new technology has to be compared with classical biofilters packed with peat or other
more rustic materials.


1.4.3.   Utilisation of activated carbon in adsorption processes.
Activated carbon produced from coal, wood, coconut or wood base is classically used for the treatment of
toxics present in industrial wastewater. At this time, the applications of adsorption, especially using activated
carbon powder and grains, in water and wastewater treatments are increasing in order to remove a large
variety of organic chemicals and some inorganic compounds which represent a health hazard. A large
number of soluble matter is found in industrial wastewaters depending on their source: aromatics, pesticides,
aliphatic hydrocarbons, volatile organic compounds (solvents, chlorinated molecules), dyes, inorganic
molecules such as ammonia or heavy metal ions. Two different technologies are carried out to apply
activated carbon in contact with wastewater. The first one is to use activated carbon powder injected in a
continuously stirred reactor. The phase separations are performed by settling or membrane filtration. The
second technique is the utilisation of fixed beds packed with activated carbon grains. Emission of
objectionable odours is a major problem for wastewater treatment and other processing facilities. Biological
treatment is a promising alternative to conventional control methods such as chemical scrubbing. Biofilters
for air pollution control are bioreactors in which waste air streams are passed through a packed bed on
which pollutant-degrading organisms are immobilised as biofilms and degrade absorbed contaminants to
harmless compounds. In the case of volatile organic compounds (VOCs) control, heterotrophic organisms
utilise VOCs as energy and as a carbon source for growth. Biofilters have been shown to work well for the
control of VOCs either as sole pollutants or as complex gas mixtures, but so far biotreatment always required
significantly larger reactor volumes than classical technologies such as chemical scrubbing. In almost all-
prior cases, air contact times in biofilters for aromatic VOCs removal have been above 40 seconds. As a
consequence, biotreatment always suffered from lower volumetric performance (hence it required larger
reactors) compared to conventional treatment methods, which allow for shorter contact times. Amongst
them, chemical scrubbing is the most established technique for odour control worldwide and is effective at
gas contact times as short as 1.3-2 seconds. Usage of new packing materials and shorter gas contact times
for biotrickling filters and biofilters for H2S treatment have shown to improve the performance of the reactors,
mostly due to larger specific surface area available for microorganisms growth and higher mass transfer
rates of the pollutant from the gas to the liquid/biofilm phase. Similar strategies to those proven for H2S may
be successful as well for VOC removal in biofiltration systems, which are waste gases targeted in the present
project. Also, packing materials with high adsorption capacities such as these of activated carbons may be
useful for attenuating peak loads, which commonly occur in real scenarios and difficult to buffer with other
packing materials. The production of AC from sludge of WWTP can be the starting-point for its wide
application as packing material for biofiltration of waste gases.


1.4.4.   Utilisation of activated carbon in biofilters for elimination of industrial waste gases.
Biological processes based upon suspended biomass, i.e. activated sludge (AS) are used for treating
industrial wastewaters. However, the toxicity of some compounds linked with the variability of flow and
concentration, usually found in these wastewaters, produces some operational problems of the AS: decrease
of efficiency removal and lack of sludge settleability. On the other hand, removal of some pollutants from
industrial wastewaters is usually carried out with activated carbon (AC) adsorption as final treatment. This
process has a major disadvantage; the need for thermal regeneration and ultimate disposal of the spent AC.
Nevertheless, a combination of both technologies, i.e. biological activated carbon (BAC), is an interesting
alternative for the above-named problems. Firstly, BAC tolerates load variations and toxic compounds better
than AS. In addition, the biomass concentration in BAC is higher than in AS, consequently higher removal
efficiency can be obtained without additional volume. With regard to AC, BAC technology decreases the
need of the AC regeneration; hence it reduces the cost of the treatment. From the viewpoint of surface area
for bio-carrier, BAC can be one of the most effective biofilm systems, due to the high specific surface area of
AC. Nevertheless, the application of BAC technology is possibly restricted by the expansive cost of AC. The
production of AC from sludge of WWTP can be the starting-point for the wide application of BAC technology
in urban and industrial WWTP. This project will test the application of BAC technology in the treatment of two
different industrial wastewaters. The first one comes from the petrochemical industry (high COD
concentration and the presence of phenolic compounds). The second one comes from the production of
fertilisers (high ammonium and low COD concentrations).




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REMOVALS, FP6-018525                                                     Periodic Activity Report


2. Summary of recommendations from previous reviews.
No recommendations from previous reviews are addressed in this report.




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REMOVALS, FP6-018525                                                             Periodic Activity Report


3. Summary of the objectives for the reporting period, work performed, contractors
   involved and the main achievements in the period.
3.1.   Fundamentals of thermophilic sludge stabilisation for the reduction and stabilisation of the
       excess and toxicity of sludges in anaerobic conditions.
During the second reporting period, at the same time the three anaerobic reactors have been maintained,
one at mesophilic conditions of 33ºC and two at the themophilic temperatures of 50ºC and 55ºC. Within this
period more conditions have been studied to complete the previous task, like changes in HRT and
combination between mesophilic-thermophilic reactors. More over a fourth reactor has been started up at
55ºC in order to produce our own innoculum for methanogenic tests measurement over the pretreatments.
The contactors involved in this objective were P1 Universitat Rovira i Virgili and P6 Gestio Ambiental i
Abastament, S.A.
The major achievement in this period has been the sustenance of three reactors during the second reporting
report without incidences and the start up of a fourth.


3.2.   Impact of the sludge pretreatment for the reduction and stabilisation of the excess and toxicity
       of sludges in anaerobic conditions.
Pre-treatments over sludge have being explored in two directions: thermal treatments and peroxide
treatments.
Thermal pre-treatments have been conducted in two different temperature ranges: 30-80ºC and
110ºC-200ºC. The distinction is made due to the different equipment used in each case: glass reactor and
autoclave, respectively. Thermal pre-treatments yield a considerable increase of the soluble COD, which
should favourably impact the sludge tranformation in the subsequent thermophilic digestion. As expected,
the temperature has a key role, and growing solubilisation has been found as temperature increases.
However, practically no organic matter removal has been observed, except for the higher temperatures and
at low extent. One hour pre-treatment seems to be enough to yield most of the solubilisation.
Hydrogen peroxide addition also result in an improvement of the soluble fraction. In this sense, probably low
doses of peroxide are desired as high doses requires much more time to be consumed with no equivalent
impact on the soluble fraction. In addition, high doses also yield direct organic matter elimination and
increase the sludge volume, both undesirable. Temperature has only some additional impact.
The contactors involved in this objective were P1 Universitat Rovira i Virgili and P6 Gestio Ambiental i
Abastament, S.A.
The major achievement in this period has been the establishment of recommended temperature and time for
thermal pre-treatment and dose, temperature and time for peroxide pre-treatment.


3.3.   Building up of a bench-scale test digestion plant for the sludge stabilisation in autothermal
       conditions.
The aerobic innoculum for the autothermal pilot plant was provided by the Reus Wastewater Treatment
plant, however the innoculum was taken at mesophilic temperature of 30ºC. Therefore, it has been
necessary to slowly acclimate these microorganisms into thermophilic ranges. The strategy followed to
acclimate the bacteria was to increase the temperature in intervals of 5ºC, starting from 30ºC, every two
weeks. The feed was made intermittently, once a day. The plant has been operated for 80 days, without
apparently troubles. Nevertheless, at present acclimate bacteria have not been yet obtained.
The contactors involved in this objective were P1 Universitat Rovira i Virgili and P6 Gestio Ambiental i
Abastament, S.A.
The major achievement in the period is the bench-scale autothermic digestion plant is totally operative.


3.4.   Theorical mixing study for the sludge stabilisation in autothermal conditions.
The work is focused on investigations about the mixing and aeration performances of the ATAD reactor (task
3.2) used by the P1. A simplification of the system (phenomena decoupling) was firstly required to be able to
study both hydrodynamics and gas-liquid mass transfer. Coupled with the rheological studies, this new



2nd reporting period                                 17
REMOVALS, FP6-018525                                                               Periodic Activity Report


experimental device will enable, in the next months, the agitation device (power number) and the global
hydrodynamics behaviour (flow regime, mixing time, kLa) to be characterised. This will constitute the basis
necessary to initiate the numerical modelling of the reactor.
The contactors involved in this objective were P1 Universitat Rovira i Virgili and P2 Université de Nantes.
The major achievement in the period is the experimental set-up for the hydrodynamic and mass transfer
determination of the Autothermal Thermophilic Aerobic Digester is built and operative.


3.5.   Determination of operating conditions for the production of hydrogen from sludge.
The second part of this objective is being undertaken. Sewage biosolid pre-treatments for improving
fermentative hydrogen production have been evaluated and enzymatic saccharification identified as the most
effective. nhancing hydrogen removal via addition of nitrogen gas into the bio-reactor headspace or contents
was evaluated and found to be effective at prolonging hydrogen production in the bio-reactor. Hydrogen
production can currently be sustained for a period of 6 hydraulic retention times (HRTs).
The contactor involved in this objective was P4 University of Glamorgan.
The major achievement of this period is the identification of optimum operating conditions for fermentative
hydrogen production.


3.6.   Extraction procedures for the utilisation of enzymes from sludge to optimise activated sludge
       digestion.
The extraction of enzymes was carried out in a first stage using activated sludge from WWTP Prague (during
a research stay at the Institute of Technology Prague), and in a second stage using sludge from WWTP
Reus (GAIASA). The extraction was performed using three different methods: ultrasound, mechanical, and
magnetic stirring disintegration, adding different compounds to improve the recovery of enzymes. The
enzymes extracted and tested were protease and lipase. Between the compounds added to improve the
extraction, the presence of a non ionic detergent (Triton X-100) had the major influence for the extraction. It
seems that the addition of a cation exchange resin and the presence of buffer have not significant effect in
the extraction.
The contactors involved in this objective were P1 Universitat Rovira i Virgili, P6 Gestió Ambiental i
Abastement S.A. and P8 Institut of Chemical Technology of Praha.
The major achievement of this period is the starting and optimization of the extraction procedure.


3.7.   Experimental assays for the utilisation of enzymes from sludge to optimise activated sludge
       digestion.
The main objective was to examine the feasibility of the enzymatic reactions in a torus reactor. In a first step,
the enzymatic elimination of phenol was experimentally studied in the torus reactor. In order to compare the
performances, several assays were also carried out with a stirred reactor. A high degree of conversion was
obtained for the enzymatic elimination of phenol in both reactors with the tested quantities of phenol. It was
concluded that, keeping a ratio of 1:1 between the phenol and the H2O2 initial molar quantities, the highest
final reaction conversion was obtained. Using the torus reactor was obtained 97% of phenol conversion
when the optimal concentrations of substrates were used. Also, a substrate inhibition was presented in the
reaction, this occurred when the H2O2 initial concentration was increased, and thus, the final reaction
conversion was lower. The excess of hydrogen peroxide in the mixture inhibited the catalytic activity of the
enzyme through the conversion of the peroxidase to inactive forms. A kinetic model based on Michaelis-
Menten with inhibition was proposed in order to have a unique kinetic model to be applied for any initial
phenol concentration. A good fitting was obtained with the proposed model for all the studied phenol
concentrations. In this way, a model that included the effect of the H2O2 and the phenol initial concentrations
and inhibitions was reached. The initial reaction rates were very similar in both reactors; however, better
phenol conversions were obtained in the torus reactor for all cases. In order to improve economically the
process, the enzyme should be used in a continuous regime over a long time period to exploit it completely.
For this reason it was necessary to immobilise the enzyme. Three different approaches for the covalent
immobilisation of the HRP were explored, concluding that, the periodate-mediated covalent immobilisation of
the HRP on Eupergit was found to be an effective method for the preparation of stable biocatalysts. In this
case, a maximum value of the immobilised enzyme activity of 126 U•g-1 was found using an enzyme loading


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REMOVALS, FP6-018525                                                                 Periodic Activity Report


on the support of 17.6 mg•g-1. The activity of the immobilised enzyme was lower than the activity of the free
enzyme. However, a high degree of phenol conversion was obtained using less concentration of enzyme.
The major achievement of this period was the study of the reaction conditions and the obtaining of the kinetic
model for the enzymatic elimination in the torus reactor.
The contactors involved in this objective were P1 Universitat Rovira i Virgili and P2 Université de Nantes.


3.8.   Numerical prediction and validation for the utilisation of enzymes from sludge to optimise
       activated sludge digestion.
The main objective of this part was the coupling of the enzymatic reaction with the numerical prediction of
hydrodynamics and the validation by comparison to experimental measurements. The enzymatic reaction of
phenol with the HRP was modelled using the CFD coupled to the kinetic model of the enzymatic reaction to
the flow simulation. Then, the reaction mechanism has to be defined to simulate the enzymatic reaction. For
this, two different strategies were studied. In the first one, while the enzyme concentration was kept small,
only two reactions were taken into consideration and no inhibition of the enzyme was analysed. The second
strategy was studied because inhibition of the reaction was found for some initial concentrations of the
reagents. The next step was the definition of the reaction rate in Fluent by the utilisation of a user-defined
function (UDF). To do this, it was necessary to write a small program in C language and coupling it to Fluent
using the UDF utility. The reaction rate was defined in the UDF utility using the kinetic parameters obtained
experimentally. After that, a patch (assignation of an initial value to variables into different cells) was done for
each initial concentration of the reagents into the reactor. Finally, to simulate the enzymatic reaction, it was
used the kinetic model with inhibition by H2O2 and taking into account the influence of the phenol initial
concentration. A very good agreement was obtained between experimental data and the CFD numerical
simulations in terms of phenol conversion, initial reaction rates and kinetic comparison. These results
allowed the possibility of optimising and scaling-up the process using the CFD modelisation.
The contactors involved in this objective were P1 Universitat Rovira i Virgili and P2 Université de Nantes.
The major achievement of this period was the numerical approach of the enzymatic elimination of phenol
using CFD.


3.9.   Characterisation of research objects for the gasification of sewage sludge.
Full characterisation (including elemental analysis, TG profiles, proximate analysis, composition of products
from thermal decomposition) of three additional samples of sewage sludge (two from Poland and one from
Prague) were done.
The contactors involved in this objective were P9 Technical University of Lodz and P8 Institute of Chemical
Technology of Praha.
The major achievement in the period is the full characterisation of sewage sludge samples.


3.10. Influence of the pyrolysis extent on gasification process for the gasification of sewage sludge.
The study performed in the first reporting period was extended. by The effect of catalytic additives (dolomite,
calcium oxide) on tar yield and gas phase composition was investigated.
The contactor involved in this objective was P9 Technical University of Lodz.
The major achievement in the period is data on the effect of different parameters on the yield, composition of
products and rate of the process. These data will be used for modelling (task 6.4).


3.11. Gasification reagent impact on the yield and kinetics for the gasification of sewage sludge.
Carbon dioxide and oxygen under nonisothermal conditions were employed to collect experimental data to
establish the effect of oxidizer on thermogravimetric and gas evolution profiles.
The contactor involved in this objective was P9 Technical University of Lodz.
The major achievement is the obtaining of data for modelling.




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REMOVALS, FP6-018525                                                               Periodic Activity Report



3.12. Identification of gasification kinetics models for the gasification of sewage sludge.
The ASTM E 698 method was used for preliminary fitting of experimental data for pyrolysis and CO2
gasification obtained at nonisothermal conditions.
The contactor involved in this objective was P9 Technical University of Lodz.
There is no major achievement in the period as the objective is under ongoing research.


3.13. Optimization of chosen method with respect to substrate production and its quality for the
      production of organic substrate from sludge for enhancement of nutrient removal.
The objective of the task was to find the optimal conditions for organic substrate production using different
methods, the main achievements in this period are following:
It was confirmed that quantity and quality of substrate produced by sludge fermentation can be controlled by
choice of sludge type, by sludge pre-treatment (disintegration for example) and by conditions of
fermentation.
The optimal types of sludge or conditions of fermentation according to the evaluated criterion are indicated in
following table:

 Benchmark                        Type of sludge              Temperature range                  Time
 COD production                   excess activated                thermophilic            > 5 days (> 2 days**)
 COD/N ratio                           primary                   psychrophilic                  < 1 day
  DNR                       not significant difference            mesophilic                    < 2 days
*for mesophilic and **thermophilic temperature
The quality of produced substrate is higher than that of ethanol based on the denitrification test.
The recommendations concerning the optimal disintegration method based on the evaluated criteria are
indicated in the following table:

 Benchmark                                                  Method of disintegration
 COD production                                             thermal
 COD/N ratio                                                thermal
 DNR                                                        thermal, freeze and thaw
 Energy consumption                                         mechanical, freeze and thaw

The contactor involved in this objective was P8 Institute of Chemical Technology of Prague, additional work
was done by P10 Technische Universität Berlin and P18 K&H Kinetic A.S.


3.14. Verification of enhancement of N and P removal for the production of organic substrate from
      sludge for enhancement of nutrient removal.
Performing batch kinetic tests of denitrification and phosphorus release with substrate produced from sludge,
the enhancement of processes was confirmed. It was found that that the extent of enhancement is
comparable with external substrate addition. The methods chosen for further continuous long term
experiments were mechanical, thermochemical and ultrasound disintegration.
The main achievements of the period are following: The highest phosphorus release rate was measured with
mechanically disintegrated activated sludge used as a source of organic matter. According the actual results,
the organic substrate released by mechanical disintegration can be successfully used as a substrate for
denitrification. The system can also efficiently nitrify the surplus ammonia nitrogen coming into the system
with the substrate produced from sludge. The efficiency of nitrogen and phosphorus removal improved in
comparison to the control model reactor. A longer period of operation is necessary for the evaluation of
thermal disintegration and disintegration of activated sludge by ultrasound, because change of activated




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REMOVALS, FP6-018525                                                               Periodic Activity Report


sludge characteristics seems to be bigger and long-term disintegration can have deteriorating effect on the
sludge.
The contactor involved in this objective was P8 Institute of Chemical Technology of Prague.


3.15. Optimisation of process implementation in wastewater treatment technology for the production
      of organic substrate from sludge for enhancement of nutrient removal.
Experimental work was focused on the operation of lab scale sequencing batch reactors treating municipal
wastewater enriched by nitrogen to achieve low COD/N ratio. Objective of the work was the evaluation of
other consequences related to use of organic substrate for enhancement of nutrient removal. It was found
that using the disintegration methods more benefits can be gained:
•     The improvement of denitrification and phosphorus release which contribute to improvement of N and
      P removal efficiency.
•     The minimization of surplus activated sludge production.
•     The deterioration of filamentous structure of sludge flocs which can improve the separation of
      activated sludge.
The contactor involved in this objective was P8 Institute of Chemical Technology of Prague, additional work
was done by P1 Universitat Rovira i Virgili and P18 K&H Kinetic A.S.
There is no major achievement in the period as the objective is under ongoing research.


3.16. Evaluation of an activated sludge system for nitritation for the advanced technology for the
      biological nitrogen removal of the reject water from the sludge dewatering systems.
During the second year of the REMOVALS project, two main objectives were achieved in this task. Firstly, it
was successfully carried out the start-up of a nitrifying activated sludge three-reactors system with 100% of
partial nitrification directly from the sludge of a municipal WWTP. The applied control strategy (Milestone
M8.1.) is a PI controller that controls the nitrogen loading rate (NLR) of the system with on-line
measurements of the oxygen uptake rate (OUR) in the reactors. Secondly, it was confirmed the stability of
the partial nitrification process in the long term operation (more than 6 months).
The objectives of this task are achieved in a 90% and the last part of this task will be the verification of this
technology for treating reject water with a real influent.
The contractor involved in this objective was P3 Universitat Autonoma de Barcelona.


3.17. Evaluation of an airlift reactor for nitritation using activated carbon (AC) as biocarrier for the
      advanced technology for the biological nitrogen removal of the reject water from the sludge
      dewatering systems.
During the second year of the REMOVALS project, three main objectives were achieved in this task. Firstly,
it was finalised the set-up of the nitrifying airlift pilot plant with the purchasing of the instrumentation and
control devices and the implementation and programming of the control and monitoring software. Secondly,
it was carried out the start-up of the nitrifying airlift pilot plant with activated carbon provided by P16
(Chemviron Carbon Limited). The main achievement of this start-up was the development of a system with
high partial nitrifying capacity and a hybrid distribution of the biomass: granular biomass (73%) and biofilm
over AC (27%). Finally, adsorption tests of ammonium, nitrite and nitrate were performed with the AC
provided by P16 in parallel with the operation of the pilot plant.
The objectives of this task are achieved in a 75%. The ongoing research on this task is the implementation of
an automatic control loop, based on the on-line ammonium measurement, for obtaining and maintaining the
partial nitrification process (Milestone M8.2.) and the verification of the system with a real influent.
The contractor involved in this objective was P3 Universitat Autonoma de Barcelona.




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REMOVALS, FP6-018525                                                               Periodic Activity Report


3.18. Identification of most influential operation parameter for the minimisation of sludge production
      by utilisation of biological potential in membrane bioreactors.
Both bench-scale plants were operated for 200 days at a very high sludge age of 148 d with a hydraulic
retention time of 10 h. Afterwards the hydraulic retention time of one bench-scale plant was reduced to 5h
and the influence on sludge characteristics was monitored. Further changes in operating conditions are
planed.
The contactor involved in this objective was P10 Technische Universität Berlin.
There is no major achievement in the period as the objective is under ongoing research.


3.19. Sludge characterisation for the minimisation of sludge production by utilisation of biological
      potential in membrane bioreactors.
Sludge characteristics, like filterability, dewaterability, oxygen transfer and viscosity have a strong impact on
operational and sludge disposal costs. During the operation of both plants, sludge samples were taken once
a week from the aeration tank of both plants and were analysed immediately for total and volatile suspended
solids (MLSS, VSS) concentration, dewaterability (CST), filterability (TTF), rheology and oxygen transfer
coefficient (kLa).
During the start-up of the plants sludge characteristics changed dramatically. Due to the high sludge age
Total Solids concentration increased from initially 7 g/L to 25±1 g/L. The increase in Total Solids
concentration lead to an increase in viscosity, a poorer filterability, a poorer dewaterability and a slightly
lower oxygen transfer. The results obtained are well within the range reported in literature.


3.20. Identification of suitable MBR sludge treatment method for the minimisation of sludge
      production by utilisation of biological potential in membrane bioreactors.
For the identification of suitable sludge treatment methods we have done some screening tests with a test
unit supplied by Salsnes Filter AS to see whether their Salsnes Filter is useful for sludge thickening. These
tests were already done and the evaluation of the results is still in progress.


3.21. Influence of power ultrasound as pre-treatment process for the destruction of organic
      compounds in sewage sludges suspensions by ultrasound and catalytic wet air oxidation.
The objectives were to investigate the combination of ultrasonication (which should ensure the breaking of
insoluble macromolecules in the solid phase of the sludge and favour their solubilization in the liquid phase)
and of catalytic wet air oxidation in the presence of heterogeneous catalysts (the higher solubilization of the
solid organic matter should prevent the catalysts from deactivation by deposition of solid organic matter).
The influence of different parameters of the ultrasonic treatment was investigated on the sludge solution. The
observed effects were: a strong particle size reduction (from 274 to 4.5 μm for industrial sludge), an increase
of the COD in liquid phase (up to 1 200 mg/L), as well as the increase of TOC (up to 600 mg/L) and protein
content in the liquid phase. Ultrasound power and sonication time have similar positive effects: for a
maximum effect, a power of 200 W during 60 min is necessary. There is an optimum concentration of sludge
of 12 g/L (of dry solid) for municipal sludge. It was also found that it is better to operate without temperature
control.
The contractor involved in this objective were P13 Institut de recherches sur la catalyse et l’environnement
de Lyon (CNRS) and P5 Institut National Polytechnique de Toulouse.


3.22. Synthesis and characterization of catalysts for the destruction of organic compounds in
      sewage sludge suspensions by ultrasound and catalytic wet air oxidation.
The objectives were to investigate the combination of sonication (which should ensure the breaking of
insoluble macromolecules in the solid phase of the sludge and favour their solubilization in the liquid phase)
and of catalytic wet air oxidation in the presence of heterogeneous catalysts (the higher solubilization of the
solid organic matter should prevent the catalysts from deactivation by deposition of solid organic matter).
Different Pt and Ru catalysts were prepared on oxide supports (TiO2, ZrO2 and CeO2) which were tested in a
batch reactor in the WAO of three different sludges (one municipal sludge, two industrial sludges) with an



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REMOVALS, FP6-018525                                                               Periodic Activity Report


initial TOC content of ca. 3 g/L. The temperature was 190°C, the partial pressure of air 37 bar. The effect of
a sonication pre-treatment was examined, by analysing the TOC content of the residual organic solid and the
TOC content in the oxidized liquor, as well as the global TOC abatement in the sludge suspensions. The
sonication pre-treatment, was not effective enough in the solubilization of the suspended matter. As a result
of the disintegration by the ultrasounds, the organic solid is in a more finely divided state which favours even
more its adsorption on the surface presented by the solid catalyst. The beneficial effect of partial
solubilization is annealed and the global TOC conversion is not significantly improved. This was confirmed
by performing similar experiments using mechanical disintegration by an ultra-Turrax as a pre-treatment
method. On the other hand, a thermal pre-treatment of the sludge at 200°C and then a catalytic WAO on the
supernatant liquor clearly demonstrated the positive effect of the addition of the solid catalysts prepared.
The contractor involved in this objective was P13 Institut de recherches sur la catalyse et l’environnement de
Lyon (CNRS).


3.23. Operation in a continuous trickle bed reactor for the destruction of organic compounds in
      sewage sludges suspensions by ultrasound and catalytic wet air oxidation.
The objective of this task is the operation in a continuous trickle bed reactor, which will be investigated
during the coming last twelve months. Based on the results of the Task 2 in the batch reactor, these catalytic
experiments will be performed on the oxidized liquor recovered after a first thermal treatment, to check the
stability of the selected catalysts on a long-term experiment. The continuous reactor which will be used for
the first experiments by P13 is constructed and ready for the planed experiments.
The contractor involved in this objective was P13 Institut de recherches sur la catalyse et l’environnement de
Lyon (CNRS).


3.24. Identification of user requirements for the production of activated carbon from sludge.
This objective was completed in the first reporting period, but through further feedback with URV (partner 1)
and partner 5 (INP) it was determined that additional items could be included in this deliverable. For
example, a key requirement of WPs 13 and 14 was a high hardness, i.e., resistance to attrition. It was,
moreover, determined that a high tendency towards the leaching of metals was not desirable.
The contactors involved in this objective were P14 Imperial College of Science, Technology & Medicine, P1
Universitat Rovira i Virgili and P5 Institut National Polytechnique de Toulouse.
The major achievement in the 12-24 month period was the refinement by addition of further user
requirements.


3.25. Start-up of the bench scale pilot plant for the production of sludge-based adsorbents for the
      production of activated carbon from sludge.
This activity was completed in the first 12 months, although it should be noted that a modification was made
to the chemical activation apparatus in the 12-24 month report. In short, the material from which the reactor
and the sample crucible was fabricated (quartz) was substituted for an alumina-based material (alsint).
Quartz had been found to react with the alkali-metal based reagents (for example, KOH), with detrimental
consequences to the integrity of the reactor and the crucible. The modification was successful.
The contactor involved in this objective was P14 Imperial College of Science, Technology & Medicine.
The major achievement was the successful modification of the chemical activation rig to circumvent the
destructive consequences of the reaction between the metal alkali-based reagents and the reactor and
crucible.


3.26. Production of SBA under known operating conditions for the production of activated carbon
      from sludge.
This task was completed in the first reporting period. However, it should be stated that in the 2nd reporting
period, P16 (CCC) became active in this task through their assistance in the large scale (i.e., in the order of
kgs) production of SBAs by carbonisation.




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REMOVALS, FP6-018525                                                            Periodic Activity Report


The contactors involved in this objective were P14 Imperial College of Science, Technology & Medicine and
P16 Chemviron Carbon Limited.
Thee were no further major achievements in this period.


3.27. Set-up and optimisation of new procedures for SBA production for the production of activated
      carbon from sludge.
The response to steam activation of the DRAW sludge was modelled using the response surface
methodology (RSM) technique. The RSM model was subsequently used to determine the optimum
conditions for activating dewatered, raw (DRAW) sludge - in the 1-12 month period, the response to steam
activation of dewatered, mesophilically, anaerobically digested (DMAD) sludge had been modelled by means
of the RSM technique. The DRAW sludge was found to be a better feedstock for the production of SBAs
with relatively high BET surface areas. The optimum steam activation conditions determined from the RSM
work was subsequently applied to French and Polish sludges supplied by P2 GPA and P9 TUL respectively.
The BET surface area results suggested that aerobically digested and raw sludges represented the best
feedstock for the production of activated carbons. A range of new chemical activation reagents were
evaluated, as was the response of dried and untreated sewage sludge (as opposed to the previously
investigated carbonised sludge) to chemical activation. Untreated sewage sludge was ascertained to be an
effective feedstock. The best activant was observed to be K2CO3; BET surface areas approaching 1900
m2/g were achieved with this reagent.
The contactors involved in this objective were P14 Imperial College of Science, Technology & Medicine, P2
Université de Nantes and P9 Technical University of Lodz.
The major achievements in this period were twofold: firstly, the regime used to generate sludge was found to
have a significant impact on the sludge’s potential as an activated carbon feedstock. Secondly, chemical
activation (using K2CO3 as the activant) of untreated sludge was determined to be capable of producing
SBAs with BET surface areas approaching 1900 m2/g.


3.28. Characterisation of sludge-based adsorbents for SBA production for the production of
      activated carbon from sludge.
SBA have been characterised in terms of their phenol uptake, catalytic activity (peroxide number), CCl4
uptake, mineralogy (by XRD analysis), ball pan hardness, pH and their surface chemistry (by FTIR analysis).
The contactors involved in this objective were P14 Imperial College of Science, Technology & Medicine and
P16 Chemviron Carbon Limited.
The major achievements have been the characterisation of the uptake of adsorbate by the SBA in both the
gaseous and liquid phase, the analysis of aspects of their physical and chemical properties.


3.29. Production of tailor-made SBA for different wastewater treatment application for the
      production of activated carbon from sludge.
In the 2nd reporting period hardened carbons were produced for WPs 13 and 14 and it was ascertained that
SBAs possessing the requisite catalytic properties could be produced by the selection of the appropriate
sludge type (DRAW) and activation method (steam activation under the optimum conditions calculated from
the RSM work).
The contactors involved in this objective were P14 Imperial College of Science, Technology & Medicine, P1
Universitat Rovira i Virgili and P5 Institut National Polytechnique de Toulouse.
The major achievement was determining that the optimum SBAs for WPs 13 and 14 were produced by the
steam activation of DRAW sludge.


3.30. Final optimization of tailor-made SBA and dissemination of results for the production of
      activated carbon from sludge.
This task is not scheduled to begin until month 29, but dissemination of the work has already commenced;
further information on the publications produced can be found in section 2 of the Annex.



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REMOVALS, FP6-018525                                                              Periodic Activity Report


The contactors involved in this objective were P14 Imperial College of Science, Technology & Medicine and
P2 Université de Nantes.
The major achievement was the successful submission of two conference papers.


3.31. Wet air oxidation operating with activated carbon as catalyst for the utilisation of activated
      carbon as catalyst in wet air oxidation.
Wet air oxidation of aqueous phenol solutions will be conducted both in a batch slurry reactor and a
laboratory scale packed bed reactor operating in trickle flow regime. Conditions of temperature (120-160ºC),
oxygen partial pressure (2-8 bar) will be studied and commercial and sludge based activated carbons
produced in WP11 will be tested as catalytic material.
The contactors involved in this objective were P1 University of Rovira i Virgili and P11 University of Coimbra.
The main achievements obtained in the 2nd reporting period were twofold. Firstly, the screening of 15
different carbons (commercial and sludge based) was terminated in batch slurry reactors showing that the
less economically attractive K2CO3 activated and water or acid washed DMAD carbons are the most active
ones. As alternatives, a steam activated DMAD and a hardened steam activated DRAW carbon were
selected as candidates for continuous TBR tests. Secondly, TBR runs with the afore mentioned carbons
gave acceptable conversions of phenol and TOC at 140-160ºC and 4 bar of oxygen partial pressure
compared to the commercial carbons, but the former were not enough stable over time on stream. Finally,
the problematic of important metal leaching of the sludge based carbons due to their high ash contents could
be highlighted as a secondary pollution and more studies are necessary to address the issues of stability
and metal leaching of sludge based carbons.


3.32. Kinetic studies of model compounds and industrial effluents for the utilisation of activated
      carbon as catalyst in wet air oxidation.
Different operating conditions such as reaction temperature (120-160ºC) and oxygen partial pressure (up to
4 bar) should be evaluated either in batch or continuous runs to obtain suitable concentration reaction/space
time profiles. The experimental data would be then adjusted with a lumped kinetic model, namely the
Generalized Kinetic Model, which considers three types of compounds: easier degraded reactants;
intermediates with difficult degradation and desired end products.
The contactors involved in this objective were P1 University of Rovira i Virgili and P11 University of Coimbra.
No achievement in the period was obtained during the 2nd reporting period due to the unavailability of
suitable sludge based carbons. The actual generation of prepared carbons is not stable enough over time on
stream and generates also important metal leaching. Further progress has to be done aiming at the
preparation of carbons that are more stable and resistant to leaching in the acidic medium.


3.33. Simulation studies of trickle-bed reactors, CFD techniques for the utilisation of activated
      carbon as catalyst in wet air oxidation.
During the second reporting period, trickle-bed reactor CFD model was upgraded in order to provide a more
universal multiphase scale approach either in terms of hydrodynamic or reaction parameters. Euler-Euler k-
fluid and Volume-of-Fluid (VOF) models were developed to provide a behavior analysis in transient
conditions.
The contactor involved in this objective was P11 University of Coimbra.
The major achievement was that computational flow modeling techniques predicted successfully gas-liquid
distribution and pressure gradient, mainly with Eulerian codes. Local temperature variation and Total Organic
Carbon (TOC) profiles were evaluated axial and radially providing a more rigorous physical description of the
underlying flow process. Computational runs exhibited backmixing phenomena, poor radial mixing and
revealed the existence of hot spots in the simulated flow regime.




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REMOVALS, FP6-018525                                                              Periodic Activity Report


3.34. Adsorption for the utilisation of activated carbon as catalyst in AD-OX process.
The initial project of working on Sludge Based Activated Carbons has been achieved during the 2nd period
due to delays of the partners involved in SBAC preparation. All samples provided by ICL and GPA have
been analysed (physical and chemical analysis) then tested in batch adsorption runs with phenol as model
pollutant. Adsorption isotherms were obtained to select convenient SBAC.
The contactors involved in this objective were P5 Institut National Polytechnique de Toulouse, P14 Imperial
College of Science, Technology & Medicine, P2 Université de Nantes and P16 Chemviron Carbon Limited.
The major achievement was to prove that some SBAC (the SA_DRAW, Steam Activate Dewatered Raw) has
convenient adsorption capacity, despite law surface area.


3.35. Oxidation, active carbon behaviour for the utilisation of activated carbon as catalyst in AD-OX
      process.
All Sludge Based Activated carbons sent by ICL and GPA have been tested as catalysts to oxidize phenol.
Only first oxidation has been checked. For comparison or exploration work on commercial AC has been
extended to pharmaceuticals, and other pollutants, especially real effluents containing salts.
The contactors involved in this objective were P5 Institut National Polytechnique de Toulouse, P14 Imperial
College of Science, Technology & Medicine and P2 Université de Nantes.
The major achievements concern the convenient catalytic properties of SBAC ( especially the one selected
for its adsorption capacity (SA_DRAW).


3.36. Complete modelling towards optimal conditions for the utilisation of activated carbon as
      catalyst in AD-OX process.
The complete modelling of AD-OX process operated in our conditions is not feasible due to non isothermal
conditions. Nevertheless a simplified model will be built up. The adsorption step is now conveniently
represented even in the case of mixture of pollutants. Breakthrough curves are well simulated.
The contactor involved in this objective was P5 Institut National Polytechnique de Toulouse.
The major achievement is the reliable fixed bed adsorption model. Modelling work on the complete AD-OX
process is still in progress. A precise representation does not appear feasible now due to the important role
of thermal desorption; only a simplified model assuming instantaneous desorption prior to oxidation at
constant and uniform temperature will be performed.
3.37. Construction and operation of the semi industrial pilot plant for for the utilisation of activated
      carbon as catalyst in AD-OX process.
The mini automated pilot plant has been built up (deliverable 1) and validated on AD-OX process on month
15 (milestone1). It has been used first with commercial AC then with SBAC (hardened SA_DRAW) and with
several model pollutants and real wastewater. Major problems: This SA-DRAW being selected for its
adsorption and oxidation characteristics was found not strong enough. The hardened one- using PVA as a
binder- procured by ICL resulted in important foaming avoiding its use in pressurized fixed bed. The reactor
material stainless steel is not resistant to the synergetic corrosion faced when using chlorides and carbon. It
had to be changed 5 times, a new material able to undergo such corroding system is not yet available and
salted effluent are no longer used. Nevertheless the feasibility of AD-OX on SBAC and salted effluents is a
major achievement due to its industrial importance.
The contactor involved in this objective was P5 Institut National Polytechnique de Toulouse
The main achievement is then to have a very sophisticated equipment to be used for AC selection in AD-OX
process.


3.38. Experimental validation of the optimal conditions for the utilisation of activated carbon as
      catalyst in AD-OX process.
Due to the abovementioned problems of time and space temperature variations the optimal conditions will
have to be found experimentally better than from a model. Experimental work is in progress.




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REMOVALS, FP6-018525                                                            Periodic Activity Report


The main problem is to receive from WP12 partners convenient AC, both active for adsorption and oxidation,
and adapted for trickle bed operation : strong enough to undergo 50 bar, without severe foaming, etc…
The contactors involved in this objective were P5 Institut National Polytechnique de Toulouse, P14 Imperial
College of Science, Technology & Medicine, P1 Universitat Rovira i Virgili and P2 Université de Nantes.


3.39. Construction of a activated carbon fixed bed for the utilisation of activated carbon in
      adsorption processes.
This task has not begun yet as it is planed to begin from month 24 to month 30 (see schedule modification
acted in first year report).
The contactor involved in this objective was P2 Université de Nantes.


3.40. Determination of the optimal contact time for the adsorption of COD or ammonium wastewater
      with batch tests for the utilisation of activated carbon in adsorption processes.
This work has begun on month 18 and should be ended on month 33 (see schedule modification acted in
first year report). The objectives deals with determination of adsorption capacities and corresponding
adsorption contact time for organic compounds (participating to COD) and for ammonium. From month 18 to
24, optimal contact times were determined for 2 organic compounds (phenol and potassium
hydrogenophtalate) in batch tests so the millestones M15.1 has been reached. CCC partner has provided a
commercial activated carbon for performances comparison.
The contactor involved in this objective was P2 Université de Nantes.


3.41. Determination of the optimal contact time for the adsorption of dye and metal ion wastewater
      for the utilisation of activated carbon in adsorption processes.
This work has begun on month 12 and ended on month 24 (see schedule modification acted in first year
report). The objectives deals with determination of adsorption capacities and corresponding adsorption
contact time for dye and metal ions. From month 12 to 24, optimal contact times and adsorption capacities
were determined for 3 dyes (AR18, BB9, BV4) and 2 metal ions (Ni, Cu) and one metalloid (As) in batch
tests so the millestones M15.2 has been reached. CCC partner has provided a commercial activated carbon
for performances comparison.
The contactor involved in this objective was P2 Université de Nantes.


3.42. Study of AC adsorption process of COD and ammonium in continuous for the utilisation of
      activated carbon in adsorption processes.
This task has not begun yet as it is planed to begin from month 24 to month 36 (see schedule modification
acted in first year report).
The contactor involved in this objective was P2 Université de Nantes.


3.43. Study of AC adsorption process of dyes and metal ions in continuous for the utilisation of
      activated carbon in adsorption processes.
This task has not begun yet as it is planed to begin from month 24 to month 36 (see schedule modification
acted in first year report).
The contactor involved in this objective was P2 Université de Nantes.


3.44. Evaluation of biofilters’ performance parameters for the utilisation of activated carbon in
      biofilters for elimination of industrial waste gases.
The evaluation of physical-chemical characteristics of organic, inorganic and sludge-based packing materials
as well as the efficiency of biofilters packed with sludge-based carbons was carried out.




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The contactor involved in this objective was P3 Universitat Autonoma de Barcelona.
The major achievement in the period was that sludge-based carbons are a suitable material as filter bed in
biofilters, even if their major potential advantage, which is to act as buffering agent of inlet pollutant
fluctuations, does not occur during normal biofilter operation due to the presence of a water layer.


3.45. Modelling of the biofilter units for the utilisation of activated carbon in biofilters for elimination
      of industrial waste gases.
A biofiltration model was developed, calibrated and validated for toluene removal in biofilters.
The contactor involved in this objective was P3 Universitat Autonoma de Barcelona.
The major achievement in the period was the proper description of a fungal biofilter degrading toluene by
means of a model based on mass balances for the gas and biofilm phases. Physical-chemical parameters of
the model as well as biological activity parameters where determined. Also, the influence of main processes
and parameters was determined.




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4. If applicable, comment on the most important problems during the period
   including the corrective actions undertaken.

P11 University of Coimbra was unable to begin the task 13.1 Wet air oxidation operating with activated
carbon as catalyst, on month 1 as planned in the project workprogramme. The mean reason was that this
Partner did not have any trickle bed reactor available. The Coordinator decided to begin the work in
Tarragona in one of the trickle bed reactors available for the study of CWAO promoted by hydrogen peroxide
with commercial activated carbon. The work has to been done in collaboration between the two Partners.
One Ph.D. student from Coimbra began the study during the first six months. During months 7 to 12 no work
was done in this task. On the other hand, important delays in the building of the trickle bed reactor in
Coimbra were noticed. At the end of first reporting period, the building was not begun, and the most
optimistic schedule was between months 18-21. The experience of the Coordinator in these reactors allowed
to plan the beginning of experimental work after month 24 as at least one year is necessary to build the
reactor and started-up. It was decided to continue work on this task in Tarragona during the next six months
(13 to 18) as AC was supplied. During this time, the construction of reactor in Coimbra was paralysed. The
Co-ordinator decided, after approval of P11, to take the leadership of the entire work-package 13. Some
modifications were necessaries. All these modifications were approved in the Extraordinary Project Co-
ordination Committee Meeting, Barcelona, January 28th, 2008.
The modifications of the WP13 are explained as follows:
WP13.     Utilisation of activated carbon as catalyst in catalytic wet air oxidation (CWAO)

Work package number           13              Start date or starting event:                  1
Participant id                                  URV         COI        TRI          CCC          KHK
Person-months per participant                    50         48          1            1            1

Objectives

The main goal of this work will address the analysis of the Wet Oxidation technology when activated carbon
is used as catalytic promoter of the reaction process. This research is integrated in the global objective of the
present project aiming at the reduction of municipal sludge by converting these residues in added value
materials. In particular, the activated carbons will be used as catalysts in the CWO treatment of liquid
effluents. Comparison with the efficiency of other catalysts will also be carried out. The studies will be
performed at different levels, involving experimental tests in laboratory and semi-industrial pilot plant units
with trickle-bed reactors, as well as simulation analysis through Computational Fluid Dynamics techniques.


Description of work

The activities to be performed under this workpackage will begin immediately with the project, by using
commercial activated carbons and tailored modified activated carbons, which will be used for comparative
studies aiming at the analysis of the process behaviour when using activated carbons obtained from sludge.
These studies concerning activated carbons efficiency in a continuous trickle bed reactor, determination of
kinetic parameters, trickle-bed behaviour by simulation studies and validation by experimental data and
finally the construction of a semi-industrial pilot plant.

Task 13.1. Catalytic wet air oxidation operating with activated carbon as catalyst.
Wet air oxidation of aqueous organic solutions will be conducted in a laboratory scale packed bed reactor
operating in trickle flow regime. Mild conditions of temperature (120-180ºC) and oxygen partial pressure (1-9
bar) will be used. Commercial, tailored modified, and activated carbons produced in WP5 will be tested as
catalytic material. The removal of organic content will be measured using routine analytical techniques. The
loss of activated carbons due to burning-out will be measured and both the temperature and the oxygen
partial pressure modified accordingly, to minimise losses of activated carbons. Several activated carbons
from sludge will be tested.

Task 13.2. Kinetic studies of model compounds and industrial effluents.
The simulation studies of the trickle-bed reactor will require the knowledge of the kinetic expressions of the
reaction process. In this context, in a first step phenol will be used as a model pollutant. If the time is enough,



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other model pollutants as well as industrial effluents will be oxidised in the laboratory trickle-bed reactor and
different lumped models for the reaction pathway will be tested for fitting the experimental data.

Task 13.3. Simulation studies of trickle-bed reactors; CFD techniques.
The performance of the Catalytic Wet Oxidation process will be firstly achieved through computational
studies, which will involve the modelling and simulation of the trickle-bed unit through different techniques.
Computational Fluid Dynamic (CFD) tools will be especially used in order to identify the main features in the
behaviour of these systems.


Task 13.4. Construction and installation of a semi-industrial pilot plant unit.
A semi-industrial CWAO pilot plant unit will be constructed, allowing to operate p to 250ºC and 50 bar. The
pilot plant unit will have a reactor allowing feed up to 1 L/h, which represents a scale-up of one order of
magnitude from a laboratory scale reactor.

Task 13.5. Semi-industrial pilot plant tests.
The overall efficiency of the CWAO technology with activated carbon will be established through the set-up
of a semi-industrial pilot plant unit, which will allow studies near the real conditions. In a first step phenol will
be used as a model pollutant. If the time is enough, other model pollutants as well as industrial effluents will
be treated with the best activated carbon from sludge. The management of industrial effluents will allow the
access to industrial data in order to be possible to validate this treatment process.


Deliverables                                                                                            Months

D13.1             Operating conditions optimised with activated carbon as catalyst and                     24
                  phenol as model pollutant.
D13.2             Industrial pilot plant: Evaluation of the CWAO technology for semi-industrial            36
                  applications.

Milestones                                                                                              Months

M13.1             Kinetic expressions for the CWAO process with activated carbon and                       30
                  phenol as model pollutant.
M13.2             Industrial pilot plant reactor.                                                          33
M13.3             Agreement between simulation and experimental tests.                                     36

Expected result

The activated carbon produced from sludge is an efficient catalyst for Catalytic Wet Air Oxidation process.
Kinetic expressions to be used on the simulation analysis of the behaviour of the trickle-bed reactor.
Laboratory data of the trickle-bed reactor for the design of the semi-industrial pilot plant unit. Industrial
results for evaluation of the CWAO technology on the treatment of wastewaters.


Planning
The task “13.1. Catalytic wet air oxidation operating with activated carbon as catalyst.” will be conducted
along the whole project and will be directed and realised by Tarragona (P1) in collaboration with Coimbra
(P11) until month 24. The effective experimentation on this task began really on month 13. The results
presented during first year of project where directed and completed in Tarragona, URV, where the thesis
project of a Ph.D. student from Tarragona was ongoing. These studies where firstly designed as training
work for Coimbra group expecting the building of their own trickle-bed reactor. At the end of month 12, the
reactor was not yet built up or even ordered. On month 13, during a visit of Dr. Rosa Quinta Ferreira in
Tarragona, it was decided to actually begin the work in Tarragona as one reactor was free for use. At this
stage the delay of the task was evaluated to be about 12 months. This task had to have a duration of only 9
months. This time was underestimated and is not enough to make all the experiments necessaries to
optimise CWAO operating conditions, test several model pollutants and explore several activated carbons
from sludge. As this experimentation should be an iterative work because this WP is directly linked to “WP12.
Production of activated carbon from sludge.”, the task should finish at the end of the project, month 36. In


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this sense, the deliverable “D13.1 Operating conditions optimised with activated carbon as catalyst and
phenol as pollutant model.” has to be delayed until month 24 and only if a limited number of activated
carbons can be tested and just with phenol as model pollutant. In all cases, a final evolution of the
deliverable can be presented at month 36.
The task “13.2. Kinetic studies of model compounds and industrial effluents.” will be conducted from month
19 to the end of the project, month 36 and will be directed and performed in Tarragona (P1). The results
presented during first year of project conducted in Coimbra are not interesting because they were obtained in
a batch reactor. This task has to be achieved also using a trickle-bed reactor as experimental tests cannot
be carried out in a batch reactor when activated carbon is the catalyst. The reason lies in that oxidation
coupling polymerisation of phenol prevails in stirred reactors because of the low catalyst to liquid ratio
existing in this type of reactor (Stüber et al., 2003). Therefore, there is not a true elimination of the phenol as
this remains in form of polymeric chains adsorbed onto the activated carbon surface. Only in systems with a
high catalyst to liquid ratio, such as trickle regime, a high extent of oxidation is assured so that kinetics of
phenol oxidation only make sense if coming of trickle bed reactors. The design of the reactor used in this
task allows the possibility to modify the flowrate of the feed during operation. Thus, when a steady state is
reached, the conversion can be calculated an then the flowrate changed to obtain a new spatial time. As
each new steady state can be achieved in just hours, every load of activated carbon can give a set of
different space time measures at one P and T conditions. Later the data can be mathematically treated to
discriminate between kinetic models and obtain kinetic parameters. For this purpose, the Co-ordinator has a
mathematical model using simulated annealing (Eftaxias et al., 2001, 2002 and 2006) that could be used for
the determination of the kinetics. The model has to be modified for its application to the new operating
conditions. Therefore, according the above, the milestone “M13.1 Kinetic expressions for the CWAO process
with activated carbon and phenol as model pollutant.” has to be delayed to month 30.
The task “13.3. Simulation studies of trickle-bed reactors; CFD techniques.” will be conducted from month 7
to the end of the project, month 36 and will be directed and carried out by Coimbra (P11). Some results were
presented in month 12 and are promising, but the experimental results used to fit the simulation study were
not the most adequate as a Mn-Ce-O catalyst in a slurry reactor was applied. The task will need results
obtained from tasks 13.1 and 13.2 to validate the CFD model. For these reasons, the milestone “M13.3
Agreement between simulation and experimental tests.” has to be delayed to month 36.
The task “13.4. Construction and installation of a semi-industrial pilot plant unit.” will be conducted from
month 25 to the month 33 and will be directed and performed by Tarragona (P1). This task has the higher
risk of the modifications proposed. 90% of the equipments to build the semi-industrial pilot-plant were
purchased from another project and the effective construction is waiting the delivery of the a new pilot-plant
building, which is expected to be ready on month 24. For these reasons, the milestone “M13.2 Industrial pilot
plant reactor.” has to be delayed to month 33.
The task “13.5. Semi-industrial pilot plant tests.” will be conducted from month 31 to the end of the project,
month 36, and will be directed and completed by Tarragona (P1). This task is totally dependent on the
previous task. As reported in the task description, in a first step phenol will be used as a model pollutant and
the tests will be conducted only with the best activated carbon from sludge. If there is enough time, other
model pollutants as well as industrial effluents will be treated.


Timetable
Table 1 shows the new timetable of the “WP13 Utilisation of activated carbon as catalyst in catalytic wet air
oxidation (CWAO)” where the new duration of each task are draft.
Table 1. New timetable of WP13.
                                                                                                 Month
                                                                                 3   6   9 12 15 18 21 24 27 30 33 36
13.1. Catalytic wet air oxidation operating with activated carbon as catalyst.
13.2. Kinetic studies of model compounds and industrial effluents.
13.3. Simulation studies of trickle-bed reactors; CFD techniques.
13.4. Construction and installation of a semi-industrial pilot plant unit.
13.5. Semi-industrial pilot plant tests.




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Person-months
The re-definition of the work-package and its tasks has increased the number of person-months needed to
achieve the objectives. The old work-package had a work force of 86 person-months whereas the new has
101 person-months, in order to intensify the work for recover the delay. Table 2 summarises the distribution
of the work force by tasks and by Partners.
Table 2. WP13 person-months status table.
                                                                         Partner - Person-month per task
                                                                       P1      P7      P11    P16     P18
                                                               Totals
                                                                      URV      TRI     COS CCC KHK
            Catalytic wet air oxidation operating   Actual     21.50 9.00     0.50 12.00
Task 13.1
            with activated carbon as catalyst.       Plan      49.00 24.00 1.00 24.00
            Kinetic studies of model compounds      Actual      6.00  0.00             6.00
Task 13.2
            and industrial effluents.                Plan      15.00 9.00              6.00
            Simulation studies of trickle-bed       Actual      6.00                   6.00
Task 13.3
            reactors; CFD techniques.                Plan      18.00                  18.00
            Construction and installation of a semi-Actual      0.00  0.00
Task 13.4
            industrial pilot plant unit.             Plan      10.00 10.00
                                                    Actual      0.00  0.00                    0.00    0.00
Task 13.5   Semi-industrial pilot plant tests.
                                                     Plan       9.00  7.00                    1.00    1.00
                                                    Actual     33.50                  24.00 0.00      0.00
                                 Total work-package
                                                     Plan      101.00 50.00 1.00 48.00 1.00           1.00
As it is can be seen in the Table 2, P1 has now 50.00 person-months instead of the 10 in the original work-
package. P11 has now only 48.00 person-months instead of the 60 in the original work-package. P7, P16
and P18 have no modifications. P12 (COS) disappears of the work-package. The values of the present
status are the values presented in the first periodic management report.
As above commented, the increase of 15 person-months is necessary to attain all the objectives of the work-
package because some work force used during the first reporting period was not actually utilisable.
About the repartition of P11, they are maintaining 24 person-months of P11 in task 13.1 because a Ph.D.
student is working from month 1 in this task and will finish at the end of month 24. P11 presented also results
on task 13.2 that can be evaluated as 6 months of work. They are maintaining 18 person-months of P11 in
task 13.3 because they presented CFD simulation results in this task, which can also be evaluated as 6
months of work. The other 12 months of work should be done during the last 24 months of project.
About the repartition of P1, the increase of 40 person-months can be detailed as follows:
•     14 person-months in task 3.1, 2 for direction and 12 for a Ph.D. student finishing the third year of work,
•     9 person-months in task 3.2, 3 for direction and 6 for a Ph.D. student finishing the third year of work
      (the work force is low, as the experimental work will be done in task 3.1),
•     nothing in task 3.3,
•     10 person-months in task 3.4, 1 for direction and 9 for a Ph.D. student or for a contract,
•     7 person-months in task 3.5, 1 for direction and 6 for a Ph.D. student or for a contract.
All the direction will be done by permanent staff of P1. At least 33 person-months have to be contracted
during the last 18 months of project.


Budget
Obviously, the budget of the project cannot be increased. The only solution is to make a modification of the
distribution of the project devoted to this work-package. The modification will involve P1 and P11.
For P11, the original budget presented in Annex I and the costs declared were (evaluation as a description of
costs was never presented):




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                                                                            Costs (€)
                   P11 COI                                              1st year form C       Needs (1)
                                                    Annex I Costs
                                                                         (evaluation)       (evaluation)
RTD Costs
Personnel costs                                            72000.00            12000.00            36000.00
         Ph.D. 36 months                           36000.00                                36000.00
         Post-Doc 12 months                        36000.00                                    0.00
Equipment                                                  42200.00                 0.00            4200.00
         Nitrogen Analyser                         15000.00                                    0.00
         TOC Solid Analyser                        17000.00                                    0.00
         HPLC Auto-sampler                          6000.00                                    0.00
         Accessories                                4200.00                                 4200.00
Consumables                                                13000.00                0.00             5000.00
Other costs (travel)                                        7000.00             2651.55             7000.00
                     Total Direct Costs                   134200.00            14651.55            52200.00
Indirect costs                                             26840.00             2930.31            10440.00
                       Total RTD Costs                    161040.00            17581.86            62640.00

Management Costs                                              5250.00             963.22              5250.00
         Audit                                      4500.00              963.22             4500.00
         Management                                  750.00                0.00              750.00
Indirect costs                                                 150.00               0.00               150.00
               Total Management Costs                         5400.00             963.22              5400.00

                                       TOTAL               166440.00           18545.08             68040.00
                                                                              Difference            98400.00
(1)
      See explanation below.
Regarding to the P11 needs for successfully finishing the project:
•        Personnel costs: 36 months of Ph.D., 12 were for the first year of task 13.1 (used), 12 are for the
         second year of task 13.1 and the last 12 for the task 13.3. A total of 36000.00 € are needed for the
         project.
•        Equipment: the evaluation of the Co-ordinator is that no budget for equipment was consumed. As
         during the last months of project they will not do experimental work, they should maintain only
         4200.00€ of accessories for computer or software needs.
•        Consumables: 5000.00 € of consumables are maintained for the needs of the whole project.
•        Other costs (travel): all initial budget is maintained.
•        Management Costs: all initial budget is maintained.
The needs of P11 for the whole project are evaluated to be 68040.00 €. This value was calculated with the
original values facilitated by P11 before the contract.
As P11 received from Co-ordinator 101640.00€ (wire transfer with date of 14-09-2006) he has to reimburse
33600.00 €. After the reimbursement P11 will not receive more budget from the Co-ordinator to finish the
project.
With regard to P1 needs to finish the WP 13:




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                                                                                 Costs (€)
                          P1 URV
                                                                              Additional Costs
RTD Costs
Personnel costs                                                                                     56880.00
         Ph.D. 24 months (1470.00€/month)                                                   35280.00
         PAS Grup III 9 months (2400.00 €/month)                                            21600.00
Equipment                                                                                           10000.00
         Accessories to finish the building of the semi-
         industrial trickle-bed reactor                                                     10000.00
Consumables                                                                                           5000.00
Other costs (travel)                                                                                     0.00
                                          Total Direct Costs                                         71880.00
Indirect costs                                                                                       14376.00
                                           Total RTD Costs                                           86256.00

Management Costs                                                                                          0.00
         Audit                                                                                   0.00
         Management                                                                              0.00
Indirect costs                                                                                            0.00
                                 Total Management Costs                                                   0.00

                                   TOTAL                                                             86256.00
In conclusion, we even release 12144 € due to the different equipment and consumables costs of partners
P1 and P11.


References
Eftaxias A., J. Font, A. Fortuny, J. Giralt, A. Fabregat, F. Stüber, “Kinetic modelling of catalytic wet air
oxidation of phenol by simulated annealing, Applied Catalysis B: Environmental 33 (2001) 175-190.
Eftaxias A., J. Font, A. Fortuny, A. Fabregat, F. Stüber, “Nonlinear kinetic parameter estimation using
simulated annealing”, Computers and Chemical Engineering 26 (2002) 1725-1733.
A., J. Font, A. Fortuny, A. Fabregat, F. Stüber, “Catalytic wet air oxidation of phenol over active carbon
catalyst Global kinetic modelling using simulated annealing”, Applied Catalysis B: Environmental 67 (2006)
12-23.
Stüber F., I. Polaert, H. Delmas, J. Font, A. Fortuny, A. Fabregat, “Catalytic wet air oxidation of phenol using
active carbon: performance of discontinuous and continuous reactors”, Journal of Chemical Technology and
Biotechnology 76 (2003) 743-751.




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Section 2 – Workpackage progress of the period.


1.    WP1. Economical feasibility study.
Not applicable as this workpackage finished on month 6 of project. For details, see activity report of 1st
reporting period.




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2.     WP2. Reduction and stabilisation of the excess and toxicity of sludges in
       anaerobic conditions.
2.1.   Workpackage objectives and starting point of work at beginning of reporting period.
The main objective of Work Package 2 for the second year is to study the effect of thermal and chemical pre-
treatments on raw sludge. During this period it has been studied the thermal effect at a low temperature
range -30, 40, 60, 80ºC- and at high temperature ranges -110, 140, 170 and 200ºC-. Finally it has been
studied peroxidation as a hydrolysis promoter of the sludge at two different temperatures 30ºC and 60ºC. At
present ozonation over sludge is being applied, however no results will be presented in this report.
Not applicable as the objective began month 13 of project.


2.2.   Progress towards objectives.
In the range of 30-80ºC of thermal pre-treatment, the higher temperatures lead to an increase of more than
100% in soluble COD content. Moreover, TDS shows the same behaviour. This suggests that part of the
homogeneous COD (or TS content) solubilises, but no organic matter is destroyed (completely mineralised).
A rapid increase of soluble COD was observed during the first hour of pre-treatment, especially at 60ºC and
80ºC, which also correlates with the rising in TDS content; beyond this time non noticeable improvement of
the solubilisation is found.
In the thermal treatment conducted at the range 110-200ºC, the tendency is similar. Therefore, the
solubilisation increases as temperature does. Only beyond 170ºC and 8h of treatment, elimination of TS is
observed at significant extent, instead VS only is removed at 200ºC and 16 h. Although, no evident
advantages can be drawn for treatment at high temperature, it is needed to assess its impact on the
thermophilic subsequent treatment to provide a supported conclusion.
Although no significant organic removal is observed after addition of hydrogen peroxide at 30ºC at
concentration below 0.87 g H2O2/g COD, it seems to occur solubilisation of the solid part, which results in an
increase of soluble COD and TDS. A dose of 0.03 g H2O2/g COD is enough to solubilise more than 70% of
the initial soluble COD. At higher doses, 1.16 and 1.45 g H2O2/g COD, organic destruction is also observed.
There is an elimination of organic matter, expressed as VSS, in 41 and 34.5%, respectively, and also a
decrease in the solid fraction, expressed as TS, in 22.5 and 14%, respectively. However, the addition of
hydrogen peroxide at this two higher doses leads to an increase of the reaction volume, rising the residual
volume in a 31.5 and 39.5% respectively, which is in turn an unfavourable consequence.
However, in the addition of hydrogen peroxide at 60ºC, it is found a higher efficiency than at 30ºC. Up to
doses of hydrogen peroxide below 0.55 g H2O2/g COD, it is seen a removal of organic matter up to a
maximum for the ratio 0.88 g H2O2/g COD, where the elimination of TS and VS content is around 46.1 and
28.3%, respectively. The maximum removal of VSS, 37.7%, is obtained using 1.11 g H2O2/g COD.
The effect of the reaction time at the sludge pre-treated with hydrogen peroxide at 60ºC proves a higher
solubilisation of the mineral matter, however no improvement is seen in the elimination of organic matter.
On the other hand, the 3 anaerobic reactors (task 2.2 “Fundamentals of thermophilic sludge stabilisation”)
were maintained during the second reporting period, in mesophilic and thermophilic conditions.
Fore more accurate details about work achieved, see technical report, part 1, pages 3-29.
P1 Universitat Rovira i Virgili as workpackage leader and P6 Gestio Ambiental i Abastament, S.A. were
involved in this workpackage.


2.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
The sludge pre-treatment by ozonation is not started. The equipment is ready and the experiments will begin
month 25. It is expected that the experimentation will be finished by month 30. For this reason, a first version
of the deliverable D2.2 “Diagram of solid reduction as a function of the kind of pretreatment applied and its
conditions” will be presented at the end of month 24, the definitive deliverable being presented at the end of
the month 30. P1 Universitat Rovira i Virgili as workpackage leader was responsible of the delay.




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2.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast      Lead
Del. Nº Deliverable name                                  WP Nº     Date due
                                                                                delivery date     contractor
D2.2      Diagram of solid reduction as a function of the      2     30-06-08      Delivered      P1 URV
          kind of pretreatment applied and its conditions.                       30-06-2008 (*)
(*) Deliverable without ozonation experiments. Full deliverable expected 31-12-2008.


2.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast      Lead
Mil. Nº   Milestone name                                  WP Nº     Date due
                                                                                delivery date     contractor
M2.2      Pretreatments operatives.                          2      31-12-07      Delivered       P1 URV
                                                                                 30-06-08 (*)
(*) Delay caused by the ozonation device.




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3.     WP3. Sludge stabilisation in autothermal conditions.
3.1.   Workpackage objectives and starting point of work at beginning of reporting period.
Some tests were carried out on the model fluids chosen for modelling the rheological behaviour of sludge
(shear-thinning, time-dependency and viscoelasticity). Some rheological tests were run on sludge used by
Partner 1 and sent by Partner 6. A lab-scale reactor has been also constructed: it is similar (in shape and in
dimensions) to the one of Partner 1, except that it allows hydrodynamics to be investigated (transparent
material, specific instrumentation).
Not applicable as first reporting period.


3.2.   Progress towards objectives.
The model fluids consisted of aqueous solutions of CMC and xanthan gum. Different concentrations were
tested as well as the effects of both temperature and NaCl addition. All tests were performed by using
rotational rheometer PAAR Physica® MCR500. The results have shown that, whatever the concentrations,
both Xanthan gum and CMC aqueous solutions have a shear-thinning behaviour (power law modeling), and
that adding NaCl allows to remove the time-dependence of these aqueous solutions and to ensure their
stability in time (during 3 days). The creeping tests have demonstrated that the CMC aqueous solutions are
not viscoelastic for the different shear stress tested whereas the xanthan gum aqueous solutions present a
viscoelastic behaviour for the lowest shear stress. For both solutions, the viscosity decreases for increasing
temperatures. At last, some rheological tests were run on sludge used by Partner 1 and sent by Partner 6.
They have confirmed that sludge has a shear-thinning character and that, even if their solid content is quite
important (TSS = 18.5 g/L), sludge remains time-independent (identical loaded and unloaded flow curves).
Fore more accurate details about work achieved, see technical report, part 1, pages 30-43.
P1 Universitat Rovira i Virgili as workpackage leader, P2 Université de Nantes and P6 Gestio Ambiental i
Abastament, S.A. were involved in this workpackage.


3.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
A PhD student has started on last October for the study of mixing and mass transfer in ATAD bioreactor. For
the theoretical study, it has been appeared necessary to build a specific model ATAD reactor in order to
perform mixing experiments for modelling the gas-liquid mass transfer with the same mixing device that the
one used by P1 in the ATAD pilot bioreactor. The mixing device is now operational. The experimental results
will used for the set-up of the numerical model. To summarise, both the tasks 3.2. Theorical mixing study and
3.3. Experimental mixing study have a delay of six month. The work of these tasks should be completed
during the third reporting period. P1 Universitat Rovira i Virgili as workpackage leader and P2 Université de
Nantes are responsible of the delay.


3.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                                 Actual/Forecast     Lead
Del. Nº Deliverable name                                   WP Nº     Date due
                                                                                  delivery date    contractor
D3.2      Impeller design to provide good mixing and the      3      30-06-08       Forecast        P1 URV
          data for digested sludge obtained at different                            31-12-08
          HRT.


3.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                                 Actual/Forecast     Lead
Mil. Nº   Milestone name                                   WP Nº     Date due
                                                                                  delivery date    contractor
M3.2      Numerical mixing study                              3      31-03-08       Forecast        P1 URV
                                                                                    31-12-08




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REMOVALS, FP6-018525                                                                Periodic Activity Report


4.     WP4. Production of hydrogen from sludge.
4.1.   Workpackage objectives and starting point of work at beginning of reporting period.
•      To investigate operating conditions for fermentation of sewage sludge giving a maximal yield of H2 and
       fermentation products for anaerobic digestion.
•      To evaluate the technical and economic feasibility of fermentation of sewage sludge to H2.
•      To make recommendations on the applicability of this technology to sewage treatment works of a
       range of scales.
At the start of the second reporting period, the necessary apparatus had been designed, constructed and
commissioned.


4.2.   Progress towards objectives.
The first milestone (M4.1) of this project involved the design, construct and commission of apparatus capable
of producing hydrogen and methane from sewage biosolids in a sequential, two phase digestion process.
This apparatus was constructed and commissioned in August 2007.
The next stage of the project (milestone M4.2) was to determine appropriate environmental conditions for
hydrogen production. In months 12-18, an evaluation of pre-treatment strategies appropriate to the
fermentative production of hydrogen from primary sewage biosolids (PSB) was begun. Three pre-treatment
methodologies have been evaluated. Firstly, heating the PSB to 70oC for one hour followed by enzymatic
saccharification, secondly, thermal hydrolysis of PSB, (as implemented in the CAMBI™ sludge treatment
process) and thirdly acidification of PSB to pH 2.0 for 24 hours.
When heating and enzymatic saccharification were applied to raw feedstock sludge, hydrogen production
was successfully produced. The mean yield of hydrogen during continuous fermentation was 12.19 L H2 Kg-1
volatile solids (VS). The production of hydrogen persisted for 2 days before declining.
When thermally hydrolysed (CAMBI™) or acidified PSB was used as a feedstock, no hydrogen production
was observed in the first bio-reactor. If glucose was added to the hydrogen bio-reactor during these
experiments, then hydrogen production was observed. Additionally it was determined that the same biosolids
used in the thermal hydrolysis process could be used as a feedstock for hydrogen production if subjected to
pasteurisation at 70oC for 1 hour followed by enzymatic degradation instead of thermal hydrolysis. These
findings indicated that thermal hydrolysis and acidification fail to improve the substrate quality sufficiently to
allow fermentative hydrogen production.
The duration of hydrogen production during continuous fermentation was extended by enhancing hydrogen
removal from the bio-reactor. Using nitrogen gas to sparge the bio-reactor contents proved to be more
effective that flushing just the headspace of the bio-reactor. Sparging extended the duration of hydrogen
production from 2 days to 6 days and delayed the build up of acetic acid for a similar period of time
suggesting that enhanced hydrogen removal serves to delay the onset of homoacetogenesis.
Fore more accurate details about work achieved, see technical report, part 1, pages 44-55.
P9 Technical University of Lodz as workpackage leader was involved in this workpackage.


4.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
No deviations from the project workprogramme were observed during the reporting period.


4.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                                    Actual/Forecast     Lead
Del. Nº Deliverable name                                     WP Nº     Date due
                                                                                     delivery date    contractor
         No deliverables during this reporting period




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REMOVALS, FP6-018525                                                             Periodic Activity Report


4.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                                 Actual/Forecast     Lead
Mil. Nº   Milestone name                                      WP Nº   Date due
                                                                                  delivery date    contractor
          No deliverables during this reporting period




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REMOVALS, FP6-018525                                                                Periodic Activity Report


5.     WP5. Utilisation of enzymes from sludge to optimise activated sludge
       digestion.
5.1.   Workpackage objectives and starting point of work at beginning of reporting period.
Task 5.1: Extraction of enzymes. The global objective was to evaluate different disintegration methods and
several treatments to the activated sludge with the idea of recover enzymes that could be used in
subsequent treatments of the sludge. The particular objectives were:
•      Test several disintegration techniques like mechanical disintegration, ultrasound disintegration and
       stirring for the release of enzymes (i.e protease) from activated sludge.
•      Evaluate the influence of several pre- and post- sludge treatments according to that found in literature
       (i.e. cation exchange resin, non ionic detergent, etc).
•      Evaluate different types of sludge for the recovery of the enzymes.
At the beginning of the reporting period no work was done in this task (starting date 13 month).
Task 5.2: Experimental assays. The objective was to examine the feasibility of enzymatic reactions in the
torus reactor. The particular objectives were:
•      Analysis of enzyme activity.
•      Determination of the kinetic parameters of the reaction.
•      Immobilisation of the enzyme.
•      Assays using immobilised enzyme.
At the beginning of the reporting period a preliminary study of the reaction was available (starting date 13
month).
Task 5.3 and 5.4: Numerical prediction and validation.
The main objective of this part was the coupling of the enzymatic reaction with the numerical prediction of the
hydrodynamic and the validation by comparison with the experimental data.
At the beginning of the reporting period a preliminary analysis of the numerical simulation of the reaction was
available but using a different kinetic model (starting date 18 month).


5.2.   Progress towards objectives.
Task 5.1. Extraction procedures.
In this period the work carried out consisted mainly in evaluate different disintegration methods found in
literature and apply them in order to recover the maximal enzyme activity. For the preliminary experiments, a
research stay (1 month duration) was carried out in the Institute of Chemical Technology Prague (P8), Czech
Republic, from 26/11/2007 – 21/12/2007, with the collaboration of Dr. Pavel Jenicek and Eng. Jana
Vondrysova, in order to profit their experience in sludge disintegration. During this stay, ultrasound,
mechanical and magnetic stirring disintegration of sludge was done, combining it with the addition of buffer,
cation exchange resin and non ionic detergent for the recovery of protease. Also some pretreatments like
washing of sludge and decantation were tested, to see the influence of such treatments in the enzyme
recovered. These preliminary experiments allow us to know that the previous washing of sludge was not
necessary and that it leads to the loss of enzyme. Also it was observed that the mechanical disintegration
had the same performance as the ultrasound disintegration (with the disadvantage of the excessive increase
in the temperature), and that the addition of cation exchange resin during the magnetic stirring disintegration
had a synergic effect with the non ionic detergent Triton X100, improving the enzyme extraction.
After these preliminary experiments, the work continued in Tarragona using sludge from WWTP Reus,
exploring in much more detail different conditions for the magnetic stirring disintegration. The extraction was
performed varying the temperature (low temperature using a water-ice bath, and room temperature); varying
the concentration of cation exchange resin and Triton X-100; evaluating the effect of the addition of buffer
(Tris HCl with pH 7, 7.5 and 8) and the time of disintegration. An ultrasound homogenizer equipment was
bought with the idea of compare the results obtained using magnetic stirring disintegration, varying the
concentration of Triton X-100, evaluating the effect of the addition of buffer, the time of disintegration and the




2nd reporting period                                   41
REMOVALS, FP6-018525                                                                   Periodic Activity Report


power applied during sonication. For all of these experiments the enzyme extraction was evaluated
measuring the amount of enzyme activity recovered for two enzymes: protease and lipase.
Task 5.2. Experimental assays.
The work was carried out in order to examine the feasibility of enzymatic reactions in the torus reactor. In a
first step, the analysis of the enzyme activity was carried out. Then, several assays were performed to study
the kinetic of the reaction and to determine the kinetic parameters. Once the reaction was studied, the
immobilisation procedure for enzyme immobilisation was analysed. Different procedures were carried out in
order to determine the best option. Once the enzyme was immobilised, the kinetic study of the reaction was
carried out using immobilised enzyme.
Task 5.3. Numerical prediction.
The coupling of the enzymatic reaction with the numerical prediction of hydrodynamics was carried out.
Utilisation of values obtained previously from a small reactor (100 ml) were used to affine model. Kinetic
models used in task 5.2. were evaluated by simulation for future validation.
Task 5.4. Validation.
The simulated initial reaction rates were calculated from the simulated curves of phenol conversion using the
model with the mechanism with inhibition of the enzyme. The simulated initial reaction rates were
significantly in agreement with the experimental values for the three initial concentrations of phenol. The
relative difference between simulated and experimental values were comprised in the range of 2 to 20.
Fore more accurate details about work achieved, see technical report, part 1, pages 56-72.
P1 Universitat Rovira i Virgili as workpackage leader, P2 Université de Nantes and P6 Gestio Ambiental i
Abastament, S.A. were involved in this workpackage.


5.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
Task 5.1. Extraction procedures, started on 15 October 2008, and due to the complexity of the work and the
difficulties found in the reproducibility of the results the extraction protocol is still under work. It seems that is
necessary to adjust the extraction protocol to the type of enzyme to be extracted in order to maximize its
recovery. For this reason, a new delivery date will be proposed (01-09-08) in order to have an optimized
extraction protocol for these two enzymes (protease and lipase). Work is 90% finished, but has a delay of 6
months. The task 5.2. Experimental assays, has to follow task 5.1. Work on sludge hydrolysis is not
commenced yet, but work on industrial effluents with commercial enzymes is finished. The delay is about 3
months. On the other hand, work in task 5.3. Numerical prediction and task 5.4. Validation are 80% finished
for both, with an advance of 6 months. The WP5 (Utilisation of enzymes from sludge to optimise activated
sludge digestion) is globally in advance of 3 months with the timesheet planned. In details, task 5.1 has a
delay of 6 months, task 5.2 has a delay of 3 months, task 5.3 is in advance of 6 months and task 5.4 is in
advance of 6 months. P1 Universitat Rovira i Virgili as workpackage leader and P2 Université de Nantes are
responsible of the balance.


5.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                                      Actual/Forecast       Lead
Del. Nº Deliverable name                                       WP Nº      Date due
                                                                                       delivery date      contractor
                                                                                          Forecast
D5.1      Extraction protocol.                                    5       31-12-07                         P1 URV
                                                                                          30-09-08


5.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                                      Actual/Forecast       Lead
Mil. Nº   Milestone name                                       WP Nº      Date due
                                                                                       delivery date      contractor
M5.1      Prediction of the efficiency of the torus reactor       5       30-06-08        Delivered        P1 URV
          used for enzymatic reaction.                                                    30-06-08




2nd reporting period                                     42
REMOVALS, FP6-018525                                                              Periodic Activity Report


6.     WP6. Gasification of sewage sludge.
6.1.   Workpackage objectives and starting point of work at beginning of reporting period.
•      To collect data for better understanding of the thermo-chemical processing of sewage sludge
       (devolatilisation and gasification).
•      To study the influence of the extent of pyrolysis process on subsequent gasification of the pyrolytical
       char (yield and kinetics).
•      To establish the kinetic model of the process for different gasification reagents (oxygen, carbon
       dioxide and water vapor).
At the end of the first reporting period, five municipal sewage sludges of different origin employed in the
thermogravimetric experiments were characterized. Data including elemental analysis, TG profiles,
proximate analysis, composition of products from thermal decomposition of sewage sludge samples under
well defined conditions were collected. Several factors indicating influence of the pyrolysis extent on
gasification process were established: the effect of final temperature for pyrolysis on the production of char,
influence of heating rate on pyrolysis extent, rate of gasification of char in different temperatures.


6.2.   Progress towards objectives.
In task 6.1. Characterisation of research objects, full characterisation (including elemental analysis, TG
profiles, proximate analysis, composition of products from thermal decomposition) of three additional
samples of sewage sludge (two from Poland and one from Prague) were done. One of these samples was
stabilized by liming and revealed significant impact of calcium on TG and MS profiles. The Varian GC was
installed, connected into TG-MS system, calibrated and series of experiments performed to verify MS
calibration procedures and to give more information about primary products of pyrolysis and gasification
processes for selected samples.
In task 6.2. Influence of the pyrolysis extent on gasification process, the effect of catalytic additives
(dolomite, calcium oxide) on tar yield and gas phase composition was investigated. It was found that the
catalyst is also responsible for self gasification of char occurring under an inert atmosphere.
In task 6.3. Gasification reagent impact on the yield and kinetics, the rate of gasification and evolved gas
composition under different atmospheres was measured in the temperature range from ambient to 1000°C.
Mixtures of CO2/Ar = 1/1, and O2/Ar containing from 0.5 to 20 mol-% of oxygen were used as an oxidizing
agents. Under CO2 containing atmosphere the gasification of char proceeds mainly above 700°C, whereas
in oxygen the whole process can be finished below this temperature.
Further work in this task includes:
•      experiments with steam as a reagent,
In the second reporting period task 6.4. Identification of gasification kinetic model was started. Some of the
data collected under task 6.1 and 6.3 concerning pyrolysis and CO2 gasification were used for preliminary
kinetic model development. The activation energies of the characteristic groups of reactions (lumps) were
identified using the ASTM E 698 method enables.
Further work in this task includes:
•      application of nonlinear regression for kinetic parameter estimation,
•      modelling of char gasification under different atmospheres.
Fore more accurate details about work achieved, see technical report, part 1, pages 73-90.
P9 Technical University of Lodz as workpackage leader was involved in this workpackage.


6.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
Delay on M6.1, the system set-up, synchronisation and calibration were done in first 6 moths of the project.
However calibration of mass spectrometer (MS) should be verified by gas chromatography. There was a
delay with purchase of this device. At this moment, GC is just installed in the laboratory of P9 Technical
University of Lodz.


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REMOVALS, FP6-018525                                                          Periodic Activity Report



6.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                              Actual/Forecast     Lead
Del. Nº Deliverable name                                   WP Nº   Date due
                                                                               delivery date    contractor
D6.1      Influence of the pyrolysis extent on synthesis     6     31-12-07     Delivered        P9 TUL
          gas composition and yield                                             28-02-08


6.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                              Actual/Forecast     Lead
Mil. Nº   Milestone name                                   WP Nº   Date due
                                                                               delivery date    contractor
M6.1      TG-MS set-up, synchronization and calibration      6     31-12-06     Delivered        P9 TUL
                                                                                31-05-08
M6.3      Influence of the pyrolysis extent on synthesis     6     31-12-07     Delivered        P9 TUL
          gas composition and yield                                             31-12-07
M6.4      Experimental data for kinetic modelling of         6     30-06-08     Delivered        P9 TUL
          gasification                                                          30-06-08




2nd reporting period                                44
REMOVALS, FP6-018525                                                               Periodic Activity Report


7.     WP7. Production of organic substrate from sludge for enhancement of nutrient
       removal.
7.1.   Workpackage objectives and starting point of work at beginning of reporting period.
The main objective for the Work-Package 7 for months 13th – 24th was to verify the feasibility of mechanical,
ultrasound and thermal disintegration to produce organic substrate for enhancement of biological nutrient
removal from wastewater. For this purpose, four SBR models were designed and operated.
The other objective was the measurement of phosphorus release rate (PRR) for testing of the possibility to
improve biological phosphorus removal process by substrate produced from sludge.


7.2.   Progress towards objectives.
During the second reporting period, work was done in the task 7.2. Optimization of chosen method with
respect to substrate production and its quality, where it was confirmed that quantity and quality of substrate
produced by sludge fermentation can be controlled by choice of sludge type, by sludge pre-treatment
(disintegration for example) and by conditions of fermentation (months 7-24).
The other work was done in the task 7.3 Verification of enhancement of N and P removal, where the
influence of substrate addition on denitrification activity of biomass and phosphate uptake was tested in
batch tests and continual experiment as well (months 13-30).
The other work was done in the task 7.4 Optimization of process implementation in wastewater treatment
technology, where the different method of technological use of substrate produced from sludge were
evaluated (months 13-30).
The main activities conducted were:
•      Development of methodology for assessment of phosphorus release rate (PRR) for testing of the
       possibility to improve biological phosphorus removal process by substrate produced from sludge.
•      Design of sequencing bath reactors for long term testing of activated sludge process with nutrient
       removal.
•      Experimental work to compare the influence of organic substrate produced by mechanical, thermal
       and thermochemical disintegration of activated sludge and by fermentation of primary sludge in
       activated sludge wastewater treatment system.
•      The comparison of activated sludge from conventional system and membrane reactor with respect to
       disintegration efficiency.
At month 24, it was planned to achieve as a milestone “Set-up of optimized parameters of disintegration
process and sludge treatment”. The following parameters were found as optimal at lab scale condition
Mechanical disintegration: Disintegrator ULTRA – TURRAX T25 Basic, disintegration time - 5 minutes, speed
- 24 000 rpm.
Thermal disintegration: Time of 10 minutes, temperature 95 ± 2 °C, standard pressure.
Ultrasonic disintegration: SONOTRODE DESINTEGRATOR, frequency 20 kHz, input power 180 W, 5
minutes.
Fermentation: Primary sludge from CWWTP of Prague was fermented in mesophilic conditions (35°C),
hydraulic retention time was 3 days.
The parameters of sludge disintegration methods determined by batch tests were evaluated by long term
sequencing batch reactor operation and it was found that another important factor must be taken into
consideration at use of disintegration methods in nutrient removal system. It is influence of the disintegration
on nitrification activity of activated sludge. From this point of view there is the risk of high salinity at the
chemical and thermochemical disintegration, which can decrease the actual nitrification activity. The
optimized process should be used in this case, when thickened sludge as more as possible is used for
disintegration and hence the salinity can be decreased to acceptable level.
For more accurate details about work achieved, see technical report, part 2, page 93-107.
P8 Institute of Chemical Technology Prague as workpackage leader was involved in this workpackage.




2nd reporting period                                  45
REMOVALS, FP6-018525                                                           Periodic Activity Report



7.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
No deviations from the project workprogramme were observed during the reporting period. However the
change in next period is planned: The programme of the task 7.4 “Optimization of process implementation in
wastewater treatment technology” has to be finished until 30th month. We suggest continuing with the task
until month 36, because of new aspects related to long term operation of SBR rectors mentioned in technical
report.


7.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast     Lead
Del. Nº Deliverable name                                    WP Nº   Date due
                                                                                delivery date    contractor
D7.1      Optimal process condition for production of         7     31-12-07     Delivered        P8 ICT
          organic substrate with regard to quantity and                          28-02-08
          quality of substrate


7.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast     Lead
Mil. Nº   Milestone name                                    WP Nº   Date due
                                                                                delivery date    contractor
M7.2      Set-up     of    optimized    parameters     of     7     30-06-08     Delivered        P8 ICT
          disintegration process and sludge treatment.                           30-06-08




2nd reporting period                                 46
REMOVALS, FP6-018525                                                                  Periodic Activity Report


8.     WP8. Advanced technology for the biological nitrogen removal of the reject
       water from the sludge dewatering systems.
8.1.   Workpackage objectives and starting point of work at beginning of reporting period.
The aim of this WP is the study and application of the most advanced biological technology in the treatment
of the liquor from the dewatering of the digested sludge (reject water). This internal process stream contains
up to 25% of the total nitrogen load of the influent of the WWTP. Normally the reject water is recycled to the
WWTP but a separate treatment of this water can significantly save in cost and area demand in upgrading
WWTP. The advanced technologies tested (nitrifying activated sludge and airlift reactor with activated
carbon as biocarrier) will be based on biological nitrogen removal via nitrite. The final objective is the
optimisation of these technologies for its implementation in full-scale WWTPs.


8.2.   Progress towards objectives.
Activities of P3 in WP8 were related to task 8.1 “Evaluation of an activated sludge system for nitritation” and
task 8.2 “Evaluation of an airlift reactor for nitritation using activated carbon (AC) as biocarrier”. During the
last year the progress in the task 8.1 could be summarized as follows:
Regarding to task 8.1, the start-up of a nitrifying activated sludge system with partial nitrification directly from
the sludge of a municipal WWTP was successfully carried out. The activated sludge pilot plant was
inoculated with biomass from the municipal WWTP of Manresa (Barcelona, Spain). The operational
conditions in the activated sludge pilot plant during the whole start-up period were fixed according to the
results obtained in the first year. The applied automatic control strategy was chosen according to Milestone
8.1 “Decision of the best control strategy for nitritation performance and stability in the activated sludge
system”. The objective was obtained in only 30 days with a very low ammonium concentration in the effluent,
high nitrogen loading rate (NLR) and 80% of nitrite accumulation. The second objective in this period was the
assessment of the stability of the partial nitrification process in the long term. This stability was verified with a
continuous operation of the controlled activated sludge system during 4 months. During this period, the
percentage of nitrite accumulation increased up to 99 % with a very low TAN concentration in the effluent.
This high value of nitrite accumulation was maintained constant for 3 months without considerable
disturbances and the objective was entirely achieved.
Regarding to task 8.2, the finalization of the set-up of the nitrifying airlift pilot plant was carried out with the
purchasing of the instrumentation and control devices and with the implementation and programming of the
control and monitoring software. The sensors installed in the airlift reactors cover: temperature, pH and
dissolved oxygen (DO), which are the main process variables for monitoring and control of the nitrification
process. The actuators cover the feeding of the reactor, the addition of base (sodium carbonate) to control
the pH, a control valve to regulate the air flow and to control the DO concentration of the liquid phase and an
electric resistance to maintain the desired temperature in the reactor. All these sensors and actuators are
either connected to specific controllers (temperature) or to a Programmable Logic Controller (PLC) which
allow the monitoring of the system in a PC and the management of the basic operating conditions set points.
The start-up of the nitrifying airlift pilot reactor was the second objective completely achieved in this task.
Activated sludge from a municipal WWTP was used as inoculum (25 L from the main biological reactor of the
Manresa municipal WWTP, Barcelona, Spain). The reactor was loaded with 2.5 kg (4% of total reactor
volume) of activated carbon (AC) produced by Chemviron Carbon Limited (P16), with a mean diameter of 1.2
                                      -1
mm and wet density of 1.25 g mL . The volumetric NLR (NLRv) was manually controlled and it was allowed
to increase if TAN in the effluent was not too high. After a period of 100 days of continuous operation of the
airlift pilot plant reactor the volumetric nitrification rate obtained was about 0.4 g N L-1 d-1 and the start-up
was successfully finished. Finally, the operation of the nitrifying airlift reactor was driven to achieve a 98% of
partial nitrification to nitrite through an increasing NLRv together with a relatively low air flow rate. This
operational strategy successfully resulted in an oxygen limited system (i.e. a biofilm partially penetrated by
oxygen) allowing nitrite building up in the reactor at NLRv as high as 0.75 gN L-1d-1.
Overall at the end of the 24th month of the REMOVALS project, we have achieved the objective of the
milestones M8.1 “Decision of the best control strategy for nitritation performance and stability in the activated
sludge system” and M8.2 “Decision of the best control strategy for nitritation performance and stability in the
airlift reactor”. Moreover, we successfully finished the deliverable D8.1 “Report on the design,
implementation and start-up of the activated sludge and airlift systems”.
For more accurate details about work achieved, see technical report, part 2, page 108-118.
P3 Universitat Autonoma de Barcelona as workpackage leader was involved in this workpackage.


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REMOVALS, FP6-018525                                                                Periodic Activity Report



8.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
A deviation of 3 months in the workprogramme of task 8.2 existed at the beginning of the second period due
to the delay in the construction of the airlift pilot plant. However, this delay had been recovered during this
year and currently there are not deviations in the workprogramme of WP8. On the other hand, due to the
lack of sludge-based activated carbon produced by the other partners of the REMOVALS project, we
decided to work in this WP with the activated carbon provided by P16 (Chemviron Carbon Limited). In the
next year, if the sludge-based activated carbon is provided by the others partners, we will test it in a scale-
down system of the airlift pilot plant.


8.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                                    Actual/Forecast     Lead
Del. Nº Deliverable name                                         WP Nº   Date due
                                                                                     delivery date    contractor
D8.1      Report on the design, implementation and                 8     31-12-07     Delivered       P3 UAB
          start-up of the activated sludge and airlift                                24-01-08
          systems


8.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                                    Actual/Forecast     Lead
Mil. Nº   Milestone name                                         WP Nº   Date due
                                                                                     delivery date    contractor
M8.1      Decision of the best control strategy for                8     31-08-07     Delivered       P3 UAB
          nitritation performance and stability in the                                31-08-07
          activated sludge system
M8.2      Decision of the best control strategy for                8     31-12-07     Delivered       P3 UAB
          nitritation performance and stability in the airlift                        15-03-08
          reactor




2nd reporting period                                      48
REMOVALS, FP6-018525                                                               Periodic Activity Report


9.     WP9. Minimisation of sludge production by utilisation of biological potential in
       membrane bioreactors.
9.1.   Workpackage objectives and starting point of work at beginning of reporting period.
This work package aims at the reduction of excess sludge production by utilisation of maintenance
metabolism in membrane bioreactors (MBR) which has not been applied so far in existing plants due to
rising viscosities and decreasing oxygen transfer rates at higher MLSS concentrations. Variation of operating
parameters (reactor volume, loading rates, sludge retention times (SRT)) should, however, enable
exploitation of maintenance potential at lower MLSS concentrations. Due to the complex nature of
wastewater, systematic investigations on the influence of operating parameters on the degree of excess
sludge minimisation are scarce. Therefore, a deeper understanding of the prevailing phenomena which will
allow an impartial ecological and economical assessment of the inherent potential is sought here. Since a
residual amount of sludge still needs to be treated and MBR sludge characteristics differ from conventional
ASP, a suitable treatment method shall be identified.
Two bench-scale membrane bioreactors (MBR) were designed and set-up for a systematic investigation of
excess sludge production as a function of operating conditions. The MBRs are of different size (10 L and 40
L, respectively) but otherwise identical and will be operated in parallel. Synthetic wastewater is chosen to
represent municipal wastewater as it enables work at defined conditions necessary for the fundamental
nature of the investigation.


9.2.   Progress towards objectives.
During the second reporting period, work was done in the task 9.2. Identification of most influential operation
parameter and task 9.3. sludge characterisation. Initially for task 9.2. both plants were operated under the
same operational conditions as a reference period. After stable conditions in both plants, the operational
conditions in one plant were systematically changed. During the operation of the plants the changes in
sludge characteristics (task 9.3) were continuously monitored.
Two submerged MBRs for C- and N-removal with identical configuration (anoxic and aerobic tank) and
identical operating conditions (HRT = 10 h, SRT = 140 d) but of different size (10 L and 40 L, respectively)
and equipped with different membrane modules (flat sheet and hollow fibre, respectively) were used to study
the sludge characteristics at a very high sludge age of 140 days. The plants were inoculated with activated
sludge from a MBR treating municipal wastewater. Both MBRs are operated at room temperature (18-23°C)
and are fed with a complex synthetic wastewater representing a municipal wastewater with a total COD of
600 mg/L. During the last year, operational conditions like HRT were changed in one plant.
The overall performance (i.e. COD removal) of the plants is assessed regularly. Sludge samples were taken
once a week from the aeration tank of both plants and were analysed immediately for total and volatile
suspended solids (MLSS, VSS) concentration, dewaterability (CST), filterability (TTF), rheology and oxygen
transfer coefficient (kLa).
Both bench-scale MBRs showed good and comparable results in terms of the C- and N-elimination rate. The
COD elimination efficiency was mostly above 97% and the TN-elimination efficiency was around 80% for
both plants.
Despite the same configuration, the same influent and the same operational conditions of both MBRs,
biomass production rate was different (~0.143 g/(L·d) and ~0.090 g/(L·d), respectively), thus resulting in
different equilibrium biomass concentrations. But the trend of the sludge characteristics was similar. With
increasing biomass concentration also apparent viscosity increases, while the viscosity for a given MLSS
concentration is different in both plants. Therefore, the viscosity of an activated sludge is not only a function
of MLSS but also a function of other sludge characteristics which have to be identified.
Increasing MLSS concentrations comes along with a poor dewaterability and a poor filterability. In
comparison to literature the obtained CST values in this study are very high, thus indicating a poor
dewaterability for both sludges. Therefore the potential to dewater these sludges is low and sludge treatment
cost would increase dramatically. Additionally, mass transfer efficiency decreases with increasing TS, thus
increasing aeration requirements. In contrast to other authors this study gave a dramatic decrease in
filterability and dewaterability and a slight decrease in mass transfer efficiency for MBRs operated at high
sludge ages.
The biodegrability of activated sludge from MBRs at high sludge ages is comparable to those of conventional
activated sludge.


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REMOVALS, FP6-018525                                                              Periodic Activity Report


For more accurate details about work achieved, see technical report, part 2, page 119-127.
P10 Technische Universität Berlin as workpackage leader, P8 Institute of Chemical Technology of Praha and
P15 Salnes Filter A.S. were involved in this workpackage.


9.3.   Deviations from the project workprogramme, and corrective actions taken/suggested: identify
       the nature and the reason for the problem, identify contractors involved.
No corrective actions.


9.4.   List of deliverables, including due date and actual/foreseen submission date.

                                                                                  Actual/Forecast     Lead
Del. Nº Deliverable name                                       WP Nº   Date due
                                                                                   delivery date    contractor
          No deliverables during this reporting period.


9.5.   List of milestones, including due date and actual/foreseen submission date.

                                                                                  Actual/Forecast     Lead
Mil. Nº   Milestone name                                       WP Nº   Date due
                                                                                   delivery date    contractor
          No milestones during this reporting period.




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REMOVALS, FP6-018525                                                                Periodic Activity Report


10. WP10. Destruction of organic compounds in sewage sludges suspensions by
    ultrasound and catalytic wet air oxidation.
10.1. Workpackage objectives and starting point of work at beginning of reporting period.
To degrade organic compounds in sewage sludge suspensions thanks to pre-treatments by power
ultrasound in order to break macromolecules and begin the solubilization of solids, then by thermal oxidation
step to achieve the solubilization of solids and finally by a catalytic oxidation process treatment of the liquid.
This workpackage WP10 was planed to start at Month 13. It started earlier in Month 9, and at the beginning
of this reporting period, samples of sewage sludges had been collected, partitioned in flasks and frozen to
get homogeneous samples for this study. The ultrasonic apparatus and analytical techniques for
characterization of treated sludge (particle size distribution, solubilized COD, TOC, total protein content)
have been set-up, as well as the batch autoclave to perform the catalytic wet air oxidation of the treated
suspensions.


10.2. Progress towards objectives.
The current activities were mainly connected with the two first tasks, Task 10.1. Influence of power
ultrasound as pre-treatment process (investigation of the influence of power ultrasound as pre-treatment
process by the characterization of the sludge before and after treatment: TOC, SM, flocs sizes, viscosity.
Influence of frequency (20 kHz, 500 kHz) and power of the wave (10-200 W) and geometry of the emitter
(horn, cuphorn, bath)) and Task 10.2 Synthesis and characterization of catalysts (Synthesis and
characterization of catalysts based on (Ru,Ti) on mixed oxide supports (TiO2, ZrO2, CeO2). Screening of the
prepared catalysts in lab scale autoclaves of the 2 step-process of wet oxidation of sewage sludge, with
analysis of the influence of the reaction parameters in the first hydrothermal step, and test of catalysts in the
second step). The work was achieved as planed. Different parameters were examined during the ultrasound
treatment of sewage sludges, demonstrating that power and time have similar positive effects (through the
key-parameter: energy=Power x time). The CWAO experiments showed that even small residual organic
solid matter may deactivate the heterogeneous catalyst, but that oxidation of the supernatant liquor after a
first thermal treatment is clearly enhanced by the addition of the prepared catalysts. Tasks 10.1 and Tasks
10.2 have been fully completed.
Task 10.3. Operation in a continuous trickle bed reactor was started recently with the set-up of the trickle-
bed reactor which will be used by P13.
During this period, it was planed to achieve as a milestone “Selection of pretreatments and reaction
conditions and of two catalysts, following the criteria of residual TOC in the solid after 1st steps of < 10% and
TOC conversion in the second step of > 80% ibn lab autoclave”. It was found, that optimal method is a
thermal pre-treatment of the suspension and a catalytic treatment of the oxidized liquor. The catalysts
selected are 3%Pt/ZrO2 and 3% Ru/ZrO2. The findings are summarized in 24 month report and will be
described in Deliverable 10.1.
For more accurate details about work achieved, see technical report, part 2, page 128-140.
P5 INP, Institut National Polytechnique de Toulouse and P13 CNRS, Institut de Recherches sur la Catalyse,
Lyon as workpackage leader were involved in this workpackage.


10.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
Work on Task 10.1: Work started in time. The initial time planed was a period of 6 months, but it went on for
12 months, because of the difficulties encountered on the heterogeneity of sewage sludges. Experiments
were repeated to check repeatability.
Work on Task 10.2: Work started in Month 9 instead of Month 13 and effective work was performed during
this second reporting period in parallel to Task 10.1.
Work on Task 10.3 planed to start in Month 19, started only in Month 23. The continuous reactor is in
operation to start the catalytic experiments on the liquid phase issued from the pre-treatment step.
P5 INP, Institut National Polytechnique de Toulouse and P13 CNRS, Institut de Recherches sur la Catalyse,
Lyon as workpackage leader were involved in this workpackage.



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REMOVALS, FP6-018525                                                           Periodic Activity Report



10.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast     Lead
Del. Nº Deliverable name                                    WP Nº   Date due
                                                                                delivery date    contractor
D10.1     Samples and performances of 12 catalysts and       10     30-06-08       Planed        P13 IRC
          of the different steps of the process                                   31-08-08


10.5. List of milestones, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast     Lead
Mil. Nº   Milestone name                                    WP Nº   Date due
                                                                                delivery date    contractor
M10.1     Selection of pretreatments and reaction            10     31-12-07     Delivered       P13 IRC
          conditions and of two catalysts following the                          30/06/08
          criteria of residual TOC in the solid after 1st
          step of < 10% and TOC conversion in the
          second step of > 80% in lab autoclave




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REMOVALS, FP6-018525                                                    Periodic Activity Report


11. WP11. Excess sludge reduction by dewaterability.
Not applicable as this workpackage will begin on month 25 of project.




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REMOVALS, FP6-018525                                                            Periodic Activity Report


12. WP12. Production of activated carbon from sludge.
12.1. Workpackage objectives and starting point of work at beginning of reporting period.
The objectives of WP12, which are unchanged from those given in the 1st reporting period, are:
•     To produce and characterise sludge-based adsorbents/catalysts under different experimental
      conditions
•     To establish cause-effect relationships between the characteristics of sludge-based adsorbents and
      the performance in different wastewater treatment applications
The starting point of the work at the beginning of the reporting period can be summarised as: Firstly, SBAs
had been produced under a limited range of different experimental conditions. Secondly, the cause-effect
relationships between the characteristics of sludge based adsorbents in different wastewater treatment
(WWT) applications had yet to be established.


12.2. Progress towards objectives.
Progress towards completing first objective (production           and   characterisation   of    sludge-based
adsorbents/catalysts under different experimental conditions).
In the first reporting period, SBAs were produced by carbonisation, physical (CO2 and steam) activation and
chemical activation. No new techniques have been used to produce SBAs, but the range of SBAs produced
by physical and chemical activation has been expanded. With regard to physical activation, a greater range
of SBAs have been produced by increasing the range of feedstock sludges from two (DRAW and DMAD) to
six – the four new additions were obtained from France and Poland with the aid of P2 GPA and P9 TUL
respectively. The new sludges have been found to exhibit a wide range of responses to the steam activation
conditions optimised using the DMAD and DRAW sludges: their BET surface areas ranged from 12.3 m2/g -
206.2 m2/g and their carbon content ranged from 0.3-34.6 wt.%. In terms of CO2 activation, the maximum
temperature used to produce SBAs has been increased from 900 ºC to 925 ºC.
Significant advances have been made in producing varied SBAs via chemical activation. Firstly, the sludge
feedstock used to produce chemically activated SBAs were expanded to encompass not only carbonised
sludges, but also dried and untreated sludges. Untreated sludges yielded particularly high BET surface
areas. A further advance was made in the range of chemical activation reagent tested; in addition to KOH,
the reagents K2CO3, K3PO4, CaCl2, MgCl2 and KCl were evaluated. The SBAs produced by using these
chemical activants, from untreated DMAD and DRAW sludges, exhibited BET surface areas that ranged from
376 to 1859 m2/g.
The characterisation studies of the SBAs have not been completed, but the litany of characterisation
techniques employed has been expanded to include analyses of the mineralogy (XRD analysis), surface
chemistry (FTIR analysis), gaseous CCl4 uptake, phenol uptake, peroxide number (catalytic activity) and pH.
Progress towards completing second objective (establish cause-effect relationships between the
characteristics of sludge-based adsorbents and the performance in different wastewater treatment
applications)
This objective is considered to still be under investigation, but substantial progress has been made. In
particular, the phenol adsorption of SBAs has been correlated with their surface area, as has their CCl4
uptake. In both cases, the experimental data has indicated that the surface chemistry of the SBAs was also
influential and indeed, may, at least in part, compensate for the SBAs’ low surface areas. However, their
advantageous surface chemistry was not sufficient to render the performance of the physically activated
SBAs competitive with commercial carbons.
Feedback from P1 (URV) and P5 (INP) has suggested that SBAs produced from steam activated SBAs are
effective in AD-OX, WWT processes; the cause of this has been identified as being their high catalytic
properties, which stem from their high content of catalytic metals (and compounds thereof), especially iron.
Fore more accurate details about work achieved, see technical report, part 2, pages 141-156.
P14 Imperial College of Science, Technology & Medicine as workpackage leader, P1 Universitat Rovira i
Virgili, P2 Université de Nantes, P5 Institute National Polytechnique de Toulouse, P9 Technical University of
Lodz and P16 Chemviron Carbon Limited were involved in this workpackage.




2nd reporting period                                 54
REMOVALS, FP6-018525                                                              Periodic Activity Report


12.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
It is anticipated that the objectives will be achieved by the end of the 30 month period. The sole milestone
(M12.1) and the first deliverable of this project were completed on schedule (i.e., in months 12-13). The
second deliverable, the completion of which is scheduled to coincide with this report, will not be subject to
any significant delays. However, it is fully anticipated that additions to the deliverable will occur (over and
above those required), when the other work package partners report more of their results back to the WP
leader and these are included into the sludge production programme. There is some ambiguity with regard to
the degree of precision to which the optimum SBAs have been selected and defined/characterised thus this
deliverable will continue to evolve.


12.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                                 Actual/Forecast      Lead
Del. Nº Deliverable name                                     WP Nº   Date due
                                                                                  delivery date     contractor
D12.1     Production of range of activated carbons.           12     01-07-07       Delivered        P14 ICL
                                                                                    13-09-07
D12.2     Definition and selection of optimum SBA for         12     30-06-08        Forecast        P14 ICL
          each application.                                                          31-07-08


12.5. List of milestones, including due date and actual/foreseen submission date.

                                                                                 Actual/Forecast      Lead
Mil. Nº   Milestone name                                     WP Nº   Date due
                                                                                  delivery date     contractor
          No milestones during this reporting period.




2nd reporting period                                    55
REMOVALS, FP6-018525                                                               Periodic Activity Report


13. WP13. Utilisation of activated carbon in wet air oxidation.
13.1. Workpackage objectives and starting point of work at beginning of reporting period.
The main goal of this work will address the analysis of the Wet Oxidation technology when activated carbon
is used as catalytic promoter of the reaction process. This research is integrated in the global objective of the
present project aiming at the reduction of municipal sludge by converting these residuals in added value
materials. In particular, the activated carbons will be used as catalysts in the CWO treatment of liquid
effluents. Comparison with the efficiency of other catalysts will also be carried out. The studies will be
performed at different levels, involving experimental tests in laboratorial and industrial pilot plant units with
trickle-bed reactors, as well as simulation analysis through Computational Fluid Dynamics techniques.
Regarding Tasks WP13.1 and 13.2, the starting point at beginning of second reporting period was the same
as for the beginning of the first reporting period. This is due to the fact that the work done in these tasks
during the first period by the previous WP13 leader (University of Coimbra) was not involving sludge based
carbons and therefore it was not useful to make any progress towards objectives. For starting point of TasK
WP13.3, it can be said that the performance of the Catalytic Wet Oxidation process involving simulation
activities of trickle-bed reactors has been conducted from month 7 on under the direction of Coimbra (P11).


13.2. Progress towards objectives.
During the second reporting period, progress towards objective of task 13.1. Wet air oxidation operating with
activated carbon as catalyst, was achieved in the sense that a convenient operating window (temperature
oxygen pressure and time on stream) could be established for continuous CWAO of phenol over SBACs in
TBRs. The screening of over 10 catalysts through batch oxidations allowed highlighting both the effect of
catalyst preparation (carbonisation, physical and chemical treatment) on the potential activity of SBACs for
the CWAO of phenol and the secondary problematic of metal leaching into the acidic reaction medium
originated from the intrinsically high mineral ash content of SBACs. Chemically activated carbons gave best
performance, but they are not very attractive from an economical point of view due to the high preparation
costs. Alternative and more economic SBACs (physically activated) could be proposed for continuous
operation, in particular steam activated DMAD and hardened steam activated DRAW carbons. These
carbons were subsequently tested in 72 h of time on stream experiments in a TBR. Suitable conditions of
temperature and oxygen partial pressure were determined to carry out the CWAO of phenol with acceptable,
but probably still too low conversions of phenol and TOC content. Improvement of activity could be easily
achieved by increasing either oxygen partial pressure or reactor temperature, but then carbons underwent
noticeable deactivation both due to combustion or disintegration of binder material. The problem of metal
leaching also occurred in continuous runs and monitoring of metal concentration of Fe and Cu detected
values close to the imposed threshold values by environmental legislation.
Concluding, it can be said that further studies are required to meet with the main objective. The main
inconvenient has been recognised by the work realised so far and the challenge for future studies is to
prepare in collaboration with P14 from ICL a 30-40% more active and stable SBAC that is also less prone to
metal lixiviation into the acidic reaction medium.
In Task 13.3 computational Fluid Dynamic codes were used for the purpose of multiphase reacting flow
prediction, namely based on Eulerian and Volume-of-Fluid models. Major hydrodynamic parameters such as
liquid holdup and pressure drop were already validated with the exception of catalyst wetting efficiencies
under trickle-flow regime. Also, the catalytic wet air oxidation based on manganese-cerium catalysts was
started to be modeled with Volume-of-Fluid model under transient conditions. The hydrodynamic prediction
of catalyst wetting efficiency by means of interface tracking schemes will be accomplished using level set
methods for gas-liquid-solid surface reconstruction. Further, the integration of sludge based activated carbon
kinetics in the computational model will be accomplished towards the successful implementation and
deployment of CWAO technology.
In particular, Eulerian k-fluid model was upgraded in order to provide a more universal multiphase scale
approach for the trickle-bed reactor either in terms of hydrodynamic or reaction parameters. The
hydrodynamic model validation was accomplished through the comparison of simulated pressure drop and
liquid holdup with experimental data from the literature. In a broad range of gas and liquid flows studied (G =
                               2
0.10-0.70 and L = 0.5-5 kg/m s) at different operation conditions, CFD results demonstrated the considerable
effect of operating pressure in pressure drop, whereas a minor influence was detected for the liquid holdup.
CFD runs were then performed for the catalytic wet air oxidation of aqueous phenolic acids solution. The
reactor behaviour was analysed by means of total organic carbon profiles which reflected the influence of



2nd reporting period                                   56
REMOVALS, FP6-018525                                                               Periodic Activity Report


temperature, pressure, gas-liquid flows and initial pollutant concentration when simulating the catalytic wet
air oxidation of phenolic acids in the temperature range 170-200 ºC and pressures 10-30 bar.
Afterwards, trickle-bed reactor was modeled by means of Volume-of-Fluid (VOF) model to provide a behavior
analysis in transient conditions. Fluid dynamics of the TBR is characterized by poor liquid distribution and
local temperature variation and conventional modeling techniques are unable to address these key design
issues. Therefore, the VOF code was used to investigate the dynamic performance under reaction conditions
providing a more rigorous physical description of the underlying flow process. The catalytic wet air oxidation
of phenolic pollutants was taken as example to evaluate axial and radial profiles for the total organic carbon
depletion and temperature along the packed bed. VOF model was used to understand the influence of
operating temperature in the total organic carbon distribution and to describe its interaction with chemical
oxidation reaction. The computational runs exhibited backmixing effects more pronounced for lower
operating temperatures. The mean radial temperature profiles revealed the existence of hot spots in the
simulated flow regime. Furthermore, poor radial mixing was remarked mainly at the hot spot locations
addressed in mass and thermal profiles.
Fore more accurate details about work achieved, see technical report, part 3, pages 159-178.
P1 Universitat Rovira i Virgili as workpackage leader and P11 University of Coimbra were involved in this
workpackage.


13.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
The fact is that WP13 has at least a 12 month delay in Task 13.1, mainly due to problems encountered by
P11 from Coimbra in the construction of the laboratory reactor, but also due to delayed availability of carbon
catalysts prepared from sludge precursors by P14 (ICL). Therefore, Task 13.2 could not be started on the
date fixed in the time schedule of WP13. Corrective actions are taken in the sense that a new WP leadership
(and time table) was accorded at the 18th month meeting held in Barcelona, new leader of WP13 is now P1
from URV, and all experimental work related to Tasks 13.1, 13.2, 13.4 and 13.5 will be now realised in
Tarragona by P1. Furthermore, P14 from ICL considerably speeded up the preparation of sludge based
carbons and during the 2nd reporting period all claimed carbon samples (up to 15 samples and a total of
500g) were provided in time by P14 from ICL. Enough batch and continuous experiments of CWAO of
phenol could be performed with these carbons to meet with Task 13.1 and start also Task 13.2. However,
the outcomes of the experiments revealed that the carbons are either stable but not enough active in the
phenol destruction at certain conditions of reactor temperature and pressure, or only sufficiently active but
not enough stable when increasing reactor temperature or pressure to suitable values. An additional
problematic with SBACs could be identified as metal leaching into the hot acidic reaction medium, which may
lead to a secondary contamination of the treated effluent. Concluding, delay in Task 13.1 is essentially
recovered, but future work has to be considered in collaboration with P14 from ICL to meet with the final
objective of WP13 that is to provide an active and stable carbon prepared from sludge that is also less prone
to metal lixiviation. The success and progress made in Task 13.1 is mandatory for fulfilling the objective of
Task 13.2 (to establish kinetics). The availability of a stable carbon catalyst is imperative and therefore work
of Task 13.2 has to be delayed until Task 13.1 is completed. However, it can be said that the numerical tools
for identifying parameters of lumped kinetic law from experimental data are available at URV (P1) and no
additional delay will result from the development of FORTRAN routines.
Fore more accurate details about this matter, see point 4 “comment on the most important problems during
the period including the corrective actions undertaken” of section 1.


13.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                                  Actual/Forecast      Lead
Del. Nº Deliverable name                                    WP Nº     Date due
                                                                                   delivery date     contractor
D13.1    Operating conditions optimized with sludge           13      30-06-08       Delivered        P1 URV
         based activated carbon as catalyst and phenol                               30-06-08
         as model pollutant.




2nd reporting period                                  57
REMOVALS, FP6-018525                                                            Periodic Activity Report


13.5. List of milestones, including due date and actual/foreseen submission date.

                                                                                Actual/Forecast     Lead
Mil. Nº   Milestone name                                     WP Nº   Date due
                                                                                 delivery date    contractor
          No milestones during this reporting period.




2nd reporting period                                    58
REMOVALS, FP6-018525                                                           Periodic Activity Report


14. WP14. Utilisation of activated carbon as catalyst in AD-OX process.
14.1. Workpackage objectives and starting point of work at beginning of reporting period.
•     To test activated carbon prepared from sludge in a new sequential process of water treatment for
      organic pollution AD-OX (adsorption at low temperature and atmospheric pressure then batch catalytic
      oxidation at higher temperature and pressure, achieving both pollution reduction and activated carbon
      regeneration).
At beginning of reporting period adsorption and oxidation steps have been investigated on several
commercial AC and a new mini pilot plant is being built-up especially for AD-OX tests.


14.2. Progress towards objectives.
As in September 2007 some “sludge based AC” was available from both GPA (1 sample) and ICL (4
samples) the main part of WP14 during this 2nd year has been devoted to investigate and compare the
efficiency of these sludge AC when used in AD-OX process i.e. as adsorbent then as an oxidation catalyst
on a model pollutant (phenol).
The work devoted to sludge based AC has to be divided in five parts
•     characterization of these SBAC ( chemical and physical analysis)
•     batch adsorption to derive the adsorption isotherms and compare to commercial AC. A selection of
      “convenient” sludge based AC is now available.
•     batch oxidation. Only single oxidation runs have been performed for preliminary screening.
•     use of this sludge AC in AD-OX mini plant. This last part has not been achieved due to preliminary
      experiments stressing the need of very strong AC to build the fixed bed avoiding any clogging. Most of
      experiments on the automated micro pilot plant have then been conducted with commercial activated
      carbon.
•     tests of Fenton regeneration, instead of CWAO, on SBAC (after preliminary tests on PICA S23).
Having stressed the need of enough AC mechanical strength to be used at elevated pressure, ICL has
provided hardened SBAC derived from the best SBAC tested. Its main drawback for being used in AD-OX is
due to important foaming which avoided convenient operation of the trickle bed in our conditions. Other
SBAC are then needed.
In addition to this main first part on sludge based AC we have
•     carried out some preliminary experiments on the mini automated pilot plant reactor on a more
      adapted commercial AC. A convenient duration for efficient oxidation (about 5 hrs), following a brief
      desorption due to heating was determined.
•     extended the work on pharmaceutical wastewater, investigating separately the two steps of AD-OX
      (adsorption and oxidation) for two important molecules Levodopa (Parkinson disease) and
      Paracetamol (one of the most widely spread pharmaceuticals) and starting some runs with the
      complete AD-OX protocol for Paracetamol on commercial AC. This commercial AC (PICA L 27) led to
      abnormal DCO increase while Paracetamol was completely oxidized
•     Tested a new commercial AC: PICA F22 to better understand the relations between AC characteristics
      and its performances as adsorbent and oxidation catalyst.
•     Started with a new AC regeneration method, as CWAO did not appear as efficient as initially
      expected: A Fenton type oxidation has been investigated on saturated AC after phenol. By this
      Fenton process the regeneration of PICA L 27 was improved but likely to conventional oxidation a
      DCO increase was observed. Same trends were observed on SBAC regeneration by this Fenton
      oxidation.
Fore more accurate details about work achieved, see technical report, part 3, pages 179-194.
P5 Institute National Polytechnique de Toulouse as workpackage leader was involved in this workpackage.




2nd reporting period                                 59
REMOVALS, FP6-018525                                                              Periodic Activity Report


14.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
As the quantity and variety of sludge based activated carbon procured by WP12 was limited, more work has
been devoted to commercial activated carbons.
As the results on adsorption capacity recovery by CWAO are rather disappointing it has been decided to test
a new oxidative regeneration using Fenton reagent (H202 + Fe 2+).
Very important corrosion problems have been faced on the mini pilot plant when using real salted effluents.
This task was not included in the initial program, though very important as validation step. It has to be
stopped due to corrosion but AD-OX was proved to be as efficient on salted effluents as on model solutions.
These additional tasks have involved more research workers than initially scheduled.


14.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                                  Actual/Forecast     Lead
Del. Nº Deliverable name                                       WP Nº   Date due
                                                                                   delivery date    contractor
          No deliverables during this reporting period.


14.5. List of milestones, including due date and actual/foreseen submission date.

                                                                                  Actual/Forecast     Lead
Mil. Nº   Milestone name                                       WP Nº   Date due
                                                                                   delivery date    contractor
M14.1     Build up of the microscale reactor for multiple       14     30-09-07     Delivered        P5 INP
          adsorption –oxidation cycle investigations                                01-01-08




2nd reporting period                                      60
REMOVALS, FP6-018525                                                               Periodic Activity Report


15. WP15. Utilisation of activated carbon in adsorption processes.
15.1. Workpackage objectives and starting point of work at beginning of reporting period.
From optimum SBAs produced in WP12, four different industrial synthetic wastewaters have been tested:
dyes and phenolic compounds, metal and metalloid ions in batch reactors in order to determine optimal
contact time and corresponding adsorption capacities.


15.2. Progress towards objectives.
During this 2nd year period, the different following tasks have been achieved:
•     Task 15.3 dealing with the determination of optimal conditions for adsorption of dyes and metal ions,
      on time regarding the timetable. Two metal ions (copper(II) and nickel(II)), three dyes (one acid called
      Acid Red 18 - AR18, and two basic named Basic Violet 4 - BV4 and Basic Blue 9 – BB9) and one
      metalloid element (arsenic (V)) have been tested. To assess the performances of SBA towards
      synthetic waters, the adsorption of the described pollutants is studied in terms of kinetics and
      isotherms in batch reactor.
•     Task 15.2 dealing with the determination of optimal conditions for adsorption of COD, in advance
      regarding the modified timetable. Two organic compounds (phenol and potassium hydrogenophtalate)
      have been tested. To assess the performances of SBA towards synthetic waters, the adsorption of the
      described pollutants is studied in terms of kinetics and isotherms in batch reactor.
Moreover during this period, task 15.1 dealing with construction of an activated carbon fixed bed has begun
in advance regarding the modified timetable. Taking into account the adsorption results obtained in batch
reactors, continuous adsorption tests will be realised with AR18. For a 2 days contact time, adsorption
capacity of DRAW-H2O is 48 % corresponding to 30 mg.g-1. In these conditions, a laboratory fixed bed of
volume 0.2 L should allow to remove approximately 2 g of AR18 pollutant for a flowrate of 100 mL.d-1. This
experimental conditions for continuous adsorption tests are chosen to reach a 2 days contact time for a lab
scale SBA production (approximately 70 g of SBA per column).
An finally, tasks 15.4 and 15.5 dealing with study of adsorption process of respectively COD, dye and metal
ion in continuous reactor, will begin at the beginning of the next reporting period as planed in the modified
timetable.
Fore more accurate details about work achieved, see technical report, part 3, pages 195-205.
P2 Université de Nantes as workpackage leader was involved in this workpackage.


15.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
Task 15.1. Design and construction of an activated carbon fixed bed. This task initially planed to begin month
10 was asked to be delayed of 14 months in order to obtain enough results from Tasks 15.2 and 15.3 (static
adsorption tests on the different pollutants) for an efficient design of the dynamic adsorption system. Finally,
this task has begun 2 months in advance (month 22).
Task 15.2. Determination of the optimal contact time for adsorption of COD or ammonium wastewater with
batch tests. The beginning of this task has been delayed of 7 months and the duration was increased of 6
months partly because of the recruiting of the post doctoral researcher. Although the end is planed on month
33, major part of the results is achieved.
Task 15.3. Determination of the optimal contact time for adsorption of dye and metal ion wastewater. This
task is in advanced of 5 months considering the initial scheduling, because it has been run in parallel with
Task 15.2 due to their similar approach. This task is achieved on time.
Task 15.4. Study of activated carbon adsorption process of COD. This task has been delayed of 4 months in
order to finalize results from task 15.2. The duration will be increased of 3 months and finished on month 36
so as to be run in parallel with Task 15.5 due to their similar approach.
Task 15.5. Study of activated carbon adsorption process of dyes and metal ions. This task is planed to begin
month 24 in advance of 2 months. The duration will be increased of 6 months and finished on month 36 so
as to be run in parallel with Task 15.4 due to their similar approach.



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15.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                              Actual/Forecast     Lead
Del. Nº Deliverable name                                   WP Nº   Date due
                                                                               delivery date    contractor
D15.1     Report of the AC adsorption technology for dye    15     30-06-08     Delivered       P2 GPA
          and metal ion removal of industrial                                   30-06-08
          wastewaters using AC from WWTP sludge.


15.5. List of milestones, including due date and actual/foreseen submission date.

                                                                              Actual/Forecast     Lead
Mil. Nº   Milestone name                                   WP Nº   Date due
                                                                               delivery date    contractor
M15.3     To prove the feasibility of the continuous        15     31-12-07      Forecast       P2 GPA
          adsorption treatment of industrial wastewaters                         30-04-09
          with AC from WWTP sludge.




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16. WP16. Utilisation of activated carbon in biofilters for elimination of industrial
    waste gases.
16.1. Workpackage objectives and starting point of work at beginning of reporting period.
The target of this workpackage will be to compare the capabilities of activated carbon-based biofilters versus
other biofilter packing material for treatment of odors. Four bench-scale biofilters will be tested, two of them
packed with commercial organic packing materials and two of them as activated carbon-based biofilters.
Volatile Organic Compounds (VOCs) representative of several odors sources such as solid waste treatment
facilities or wastewater treatment plants will be used as model compounds.
Starting point of work at the beginning of the reporting period was as follows. During the first reporting
period, work was finished in the task 16.1. The redesign and start-up of an existing biofiltration setup allowed
for the simultaneous operation of 4 biofilters with different packing materials. Also, work performed in the
task 16.2 in the first reporting period allowed to evaluate biofilters’ performance for toluene removal at
different gas contact time operating at medium-high gas. Additionally, some partial characterization of
physical and chemical parameters was performed for organic and inorganic packing materials other than
sludge-based carbons. Task 16.3 regarding biofilters modelling has been entirely performed in the 2nd
reporting period


16.2. Progress towards objectives.
Activities of P3 in WP16 were related to task 16.2 in the physical and chemical characterization of packing
materials and the operation in parallel of four biofilters to compare the capability of carbon-based biofilters for
treatment of target compounds against other packing materials. Also activities of P3 in WP16 were related to
task 16.3 in the modelling of biofilters. The following tasks were performed:
Regarding task 16.2, a set of packing materials (including sludge-based carbon) was characterized as to
determine the pressure drop generated by them under different operating conditions. Also, the sorption
capacity under dry and wet conditions for sludge-based carbon produced in the project and compost were
determined. Both are key parameters to assess the suitability of sludge-based carbons versus organic and
inorganic packing materials. The results obtained show that SBCs offer a higher contact surface than
traditional, organic, packing materials and their adsorption capacities are larger than any other organic and
inorganic material tested. However, such an advantage that would help buffering inlet load changes in real
biofilters is balanced when adsorption is tested under the operating conditions of a biofilter, i.e. with a layer
of water covering the surface of the SBC. Also, a VOC-treating conventional biofilter was run under
conditions comparable to those found in actual, industrial-scale systems showing relatively low toluene
elimination capacities compared to other biofiltration studies, even if toluene removal efficiency was
adequate at low concentrations. In general, a proper and conclusive experimental comparison of packing
materials with sludge-based carbons has been achieved and the objective of task 16.2 has been achieved.
Regarding task 16.3, a dynamic model aimed at simulating toluene abatement was calibrated and validated
using the experimental data obtained during the development of Task 16.2, along with previously obtained
data. The theoretical model describing the elimination of toluene in a biofilter bed was based on the mass
balance in the gas phase and within the biofilm. The set of partial differential equations was discretized in
space along the bed height and biofilm thickness. The resulting set of ordinary differential equations was
solved using MATLAB in a home-made modelling environment. The kinetic parameters were calculated
using experimental data from task 16.2. In order to determine the influence of model parameters on the
model predictions, a parametric sensitivity analysis was performed for each parameter, including all kinetic,
stoichiometric and physicochemical parameters.
                                                                       nd
Objectives of task 16.3 have been entirely achieved along the 2 reporting period since the model can
satisfactorily predict different operation scenarios, including bacterial- and fungal-based operation requiring
only few parameters. Results clearly demonstrate that a highly complex model is not necessary to properly
describe the performance of a biofilter. The major impact on model predictions was obtained for specific
surface area, partition and diffusion coefficient, according to the sensitivity analysis.
P3 Universitat Autonoma de Barcelona as workpackage leader was involved in this workpackage.
Fore more accurate details about work achieved, see technical report, part 3, pages 206-222.




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16.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
The main problem encountered during the development of the work was the lack of sludge-based activated
carbon. Instead, sludge-based carbon produced in the project was used as a first approach. According to the
results obtained, one can guess that sludge-based activated carbon will perform similarly to sludge-based
carbon in terms of biofiltration. In any case, larger sorption capacities of sludge-based activated carbons
could be tested to confirm the abovementioned. Deliverables for WP16 include a report on the biofilters
performance (D16.1, month 23) and milestones for WP16 include the comparison of the capability of the
activated carbon-based reactors versus traditional filter bed-based systems (M16.1, month 22). Both are
already prepared based on conclusions obtained for sludge-based carbon. In any case, WP 16 offers to test
sludge-based activated carbons in biofilters out of its schedule as long as sludge-based activated carbon is
provided in the next 6 months.


16.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast     Lead
Del. Nº Deliverable name                                  WP Nº     Date due
                                                                                delivery date    contractor
D16.1     Report on the biofilters performance              16      31-05-08      Delivered       P3 UAB
                                                                                  14-07-08


16.5. List of milestones, including due date and actual/foreseen submission date.

                                                                               Actual/Forecast     Lead
Mil. Nº   Milestone name                                  WP Nº     Date due
                                                                                delivery date    contractor
M16.1     Capability of carbon-based biofilters for         16      30-04-08      Delivered      P3 (UAB)
          improving treatment capabilities of current                             30-04-08
          packing materials




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17. WP17. Management & co-ordination.
17.1. Workpackage objectives and starting point of work at beginning of reporting period.
•       Address top level management, financial progress and administration of the project.
•       Ensure the timely fulfilment of the project goals.


17.2. Progress towards objectives.
Task 17.1 Project management.
The project management is based on the individual work packages and tasks defined in the project structure.
The Coordinator ensured the proper direction, the communication between partners and the European Union
and compliance with the projects overall commitments towards the European Union.
Second meeting at the end of the first reporting period was realised in Prague, July 2nd and 3rd, 2007.
Through this meeting, all the results of the different tasks and work packages were presented and reviewed
by the partners. The next topics were presented during this meeting: 6th month reports of WP2, WP3, WP4,
WP5, WP6, WP7, WP8, WP9, WP10, WP12, WP13, WP14, WP15 and WP16; dissemination, measures to
take; immediate plans for next 6 months, special focus on collaboration between Partners; administrative
and management aspects. During this meeting, a dissemination reunion was organised with local public and
private institutions. For more information, see Section 2 – Dissemination of knowledge of the Plan for using
and disseminating the knowledge.
Third meeting at the middle of the second reporting period was realised in Barcelona, January 28th and 29th,
2008. Through this meeting, all the results of the different tasks and work packages were presented and
reviewed by the partners. The next topics were presented during this meeting: 6th month reports of WP2,
WP3, WP4, WP5, WP6, WP7, WP8, WP9, WP10, WP12, WP13, WP14, WP15 and WP16; dissemination,
measures to take; immediate plans for next 6 months, special focus on collaboration between Partners;
administrative and management aspects. During this meeting, a second dissemination reunion was
organised with local public and private institutions. For more information, see Section 2 – Dissemination of
knowledge of the Plan for using and disseminating the knowledge.
Task 17.2 Accessibility to project progression.
The website is upgraded twice times a year. A private zone was created were all the documentation of the
project is accessible to all Partners.
Task 17.3. Progress reports.
Problems occurred during first reporting period were totally solved.
P1 Universitat Rovira i Virgili as workpackage leader, and all other Partners were involved in this
workpackage.


17.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
No big deviations from the workprogramme.


17.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                                  Actual/Forecast     Lead
Del. Nº Deliverable name                                      WP Nº    Date due
                                                                                   delivery date    contractor
D17.1     Reviews with the European Union.                     17      15-08-08      Forecast       P1 URV
                                                                                     15-10-08


17.5. List of milestones, including due date and actual/foreseen submission date.
Not applicable in this workpackage.




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18. WP18. Dissemination.
18.1. Workpackage objectives and starting point of work at beginning of reporting period.
•     Demonstration of the viability of experimental units with a view to their implementation in existing
      treatment plants.


18.2. Progress towards objectives.
Task 18.1 REMOVALS newsletter.
With the launch of REMOVALS website, this service was stopped. The news section has to be restarted with
a new format.
Task 18.2 REMOVALS website.
The REMOVALS website is improved twice times at year.
Task 18.3. Workshops and conferences.
Two dissemination reunions were organised in Prague (July 07) and Barcelona (January 08).
During the Prague meeting, a presentation of all partners and also a detailed description of each WP was
realised. The participants of the dissemination session were: Faculty of chemical and food Technol.
Bratislava, Slovakia, Veolia Voda a.s., Czech Republic, Cero VVV T.G.M., Prague, Czech Republic, ICT,
Prague, Czech Republic, Hydroprojekt, Č1ŽP, Vodohosp. Ponila Pler and VUT, Brně, Czech Republic.
During the Barcelona meeting, a presentation of all partners and also a detailed description of each WP was
realised. The participants of the dissemination session were: Rovira i Virgili University, Environmental
Analysis and Management research group, Spain, SIMPPLE S.A., DEISA, RUBATEC S.A., Agència
Catalana de l’aigua (ACA), Oms Sacede S.A., SECOMSA AIGÜES S.L., AREMA, CTM, Centre Tecnològic
Manresa, Cetaigua-CTM, Agbar Agua, Mancomunitat Penedes-Garraf, CI. GRAL. D’AIGÜES DE
CATALUNYA S.A., DEPURACION DE AGUS DEL MEDITERRANEO S.L., IDOM, UTE COPISA-INFILCO,
ACCIONA Agua, El Prat de Llobregat, ACCIONA Agua, La Llagosta, SOREA S.A., AUDING S.A., AQUALIA,
EDAR Tortosa, AQUALIA Gestión Integral del Agua S.A., AQUALIA, EDAR Torredembarra, Consell
comarcal del Baix Camp, CODALSA and Figueres de Serveis S.A.
Task 18.4. Confection of networks.
Work is ongoing.
Task 18.5. Dissemination material.
The primary dissemination material at this stage will be presented in the project website. Posters of each
Partner and of each workpackage are presented in both meetings, Prague and Barcelona. A lot of material is
individually prepared and presented by all Partners. 48 presentations, conferences and/or posters were
realised or are planned since the beginning of the project. For more information, see Section 2 –
Dissemination of knowledge of the Plan for using and disseminating the knowledge.
P1 Universitat Rovira i Virgili as workpackage leader, and all other Partners were involved in this
workpackage.


18.3. Deviations from the project workprogramme, and corrective actions taken/suggested: identify
      the nature and the reason for the problem, identify contractors involved.
The only relevant deviations from the work programme are in the tasks of Newsletters and Confection of
networks where the work is not totally satisfactory by lack of time. P1 Universitat Rovira i Virgili as
workpackage leader was involved in the deviations. Additionnal personnel has to be contracted to solve this
lack of information.




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18.4. List of deliverables, including due date and actual/foreseen submission date.

                                                                          Actual/Forecast     Lead
Del. Nº Deliverable name                              WP Nº    Date due
                                                                           delivery date    contractor
                                                                             Delivered
D18.3   Workshops and conferences (Prague).             18     30-06-07                     P1 URV
                                                                             02-07-07
                                                                             Delivered
D18.3   Workshops and conferences (Barcelona).          18     31-12-07                     P1 URV
                                                                             29-01-08
                                                                             Delivered
D18.4   Dissemination material (Prague).                18     30-06-07                     P1 URV
                                                                             02-07-07
                                                                             Delivered
D18.4   Dissemination material (Barcelona).             18     31-12-07                     P1 URV
                                                                             29-01-08


18.5. List of milestones, including due date and actual/foreseen submission date.
Not applicable in this workpackage.




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Section 3 – Consortium management.

1. Consortium management tasks and their achievement; problems which have occurred and how
   they were solved.
See the paragraph WP17 of section 2 for a description of Consortium management tasks and their
achievement.
Two big problems were detected:
•     The impossibility of P11 University of Coimbra to achieve the work contracted for the WP13. The
      decision to change the direction of the workpackage was taken by unanimity during the meeting in
      Barcelona, January 28th and 29th, 2008 in the Extraordinary Project Co-ordination Committee Meeting.
      For more accurate details, please see paragraph 4 “If applicable, comment on the most important
      problems during the period including the corrective actions undertaken” of section 1 “Project objectives
      and major achievements during the reporting period”.
•     P12 Cosvalado was declared in bakrupt during the year 2007. During the Extraordinary Project Co-
      ordination Committee Meeting of Barcelona, the decision to exclude this Partner was taken by
      unanimity. The exclusion of this Partner had consequences on the WP13. Again, see paragraph 4 of
      section 1 to find out how it was solved.


2. Contractors: Comments regarding contributions, changes in responsibilities and changes to
   consortium itself, if any.
As commented in the paragraph below, the Partner P12 Cosvalado was excluded of the Consortium after an
unanimal decision of the Project Co-ordination Committee.


3. Project timetable and status, including an updated, frontlined barchart. Clarify changes and
   impact on the planned milestones, if any.
The WP1 (Feasibility study) was totally delivered on time by the Consortium.
The WP2 (Reduction and stabilisation of the excess and toxicity of sludges in anaerobic conditions) has a
global delay of 6 months, caused by the delay in task 2.3. This delay was the responsible that milestone
M2.2 was delayed 6 months and deliverable D2.2 will be fully delivered only in month 30. Tasks 2.1 and 2.2
are finished, but the 3 reactors were maintained operatives during the second reporting period in order to
begin task 2.5 in month 25.
The WP3 (Sludge stabilisation in autothermal conditions) has a delay of 12 months caused by two delays of
6 months each one in the tasks 3.1. Building up of a bench-scale test plant and start-up and 3.2. Theoretical
mixing study. The delay imply a forecast delivery date of D3.2 (“Impeller design to provide good mixing and
the data for digested sludge obtained at different HRT”) by the 31-12-08, month 30. These delays do not
imply changes in the Milestones of this workpackage.
The WP4 (Production of hydrogen from sludge) is totally in line with the timesheet planned.
The WP5 (Utilisation of enzymes from sludge to optimise activated sludge digestion) is globally in advance of
3 months with the timesheet planned. In details, task 5.1 has a delay of 6 months, task 5.2 has a delay of 3
months, task 5.3 is in advance of 6 months and task 5.4 is in advance of 6 months. The delay imply a
forecast delivery date of D5.1 (“Extraction protocol”) by the 30-09-08, end of month 27.
The WP6 (Gasification of sewage sludge) is totally in line with the timesheet planned.
The WP7 (Production of organic substrate from sludge for enhancement of nutrient removal) is globally in
advance of two months with the timesheet planned.
The WP8 (Advanced technology for the biological nitrogen removal of the reject water from the sludge
dewatering systems) is globally in line with the timesheet planned, but the task 8.1. Evaluation of an
activated sludge system for nitritation is delayed 3 months and it will be finished on September 2008
whereas the task 8.2 Evaluation of an airlift reactor for nitritation using activated carbon (AC) as biocarrier is
developed on time. Task 8.3 will begin on this month and task 8.4 is advanced 3 months.




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The WP9 (Minimisation of sludge production by utilisation of biological potential in membrane bioreactors)
has globally a delay of 1 month because work in task 9.2. Identification of most influential operation
parameter has a delay of 4 months for the reason that the delivery 9.1. was delayed. Elsewhere, the task
9.3. Sludge characterisation is in advance of 3 months over the plan. Task 9.4 Identification of most suitable
MBr sludge treatment methods has not started yet.
The WP10 (Destruction of organic compounds in sewage sludges suspensions by ultrasound and catalytic
wet air oxidation) has globally a delay of 4 months. Task 10.1 (Influence of power ultrasound as pre-
treatment process) has been finished in Month 24. Experiments will still go on to clarify some aspects. Task
10.2 (Synthesis and characterization of catalysts) was achieved in Month 24. Further experiments will be
performed in parallel with Task 10.3 to better analyse the effect of temperature on the pre-treatment step.
Task 10.3 has started in Month 23 and is ongoing.
The WP11 (Excess sludge reduction by dewaterability) will begin on month 25.
The WP12 (Production of activated carbon from sludge) is globally in line with the plan. Tasks 12.1-12.3
were completed in the first reporting period. Task 12.4 can also be judged to have been completed; physical
activation using both CO2 and steam has been tested exhaustively in the case of steam activation. The
response to steam activation by both DRAW and DMAW sludge had been modelled by means of the RSM
technique and the optimum conditions for activating these sludges have subsequently been applied to
sludges sourced from France and Poland. Chemical activation has also been thoroughly investigated; whilst
the investigations have not been completed, the progress made can already be said exceed the
requirements of this task; the highest BET surface area attained is in line with the highest BET surface area
reported in the literature for a SBA. Task 12.5 is considered to be approximately 60-70 % complete and it is
anticipated that it will be completed within the 30 month deadline. With regard to task 12.6, a range of SBAs
have been produced for specific WWT applications and a selection of SBAs have been distributed to the
WPs affiliated with WP12. It is believed that this task will be completed on time. Task 12.7 is not scheduled
to start until month 30, but, as is described elsewhere in the latter part of this document, dissemination of the
results has already commenced and no problems are anticipated with regard to the completion of this task
within the allotted time period.
The WP13 (Utilisation of activated carbon as catalyst in wet air oxidation) has globally 6 months of delay
(new timetable). Task 13.1 Wet air oxidation operating with activated carbon as catalyst was started with new
WP13 leader on month 18th in Tarragona and progresses have been made testing up to 15 carbons in batch
and 3 carbons in continuous oxidation runs. The task is ongoing, because new sludge based carbons are
required that are more stable and resistant to metal leaching. However, convenient operating conditions with
respect to temperature and oxygen partial pressure have been assessed. Due to this situation, work in task
13.2 Kinetic studies of phenol over sludge based active carbon has not started yet as it makes no sense to
conduct a kinetic study with inadequate catalysts (6 month delay). Task 13.3 Simulation studies of trickle-bed
reactors:CFD techniques meets the requirements established after WP13 reformulation including both work
                                                                        rd
status and programmed timetable. Task 13.4 and 13.5 will start in the 3 reporting period.
WP14 (Utilisation of activated carbon as catalyst in AD-OX process) is globally in advance of 3 months.
Tasks 14.1 and 14.2 are achieved as scheduled initially – though complementary additional works are still in
progress. Task 14.3 is on line. Task 14.4: construction and operation of a semi-industrial pilot plant is in
advance of 3 months. Task 14.5: experimental validation of the optimal conditions has yet started (in
advance of 3 months). This advance on initial program is due to more research workers than scheduled. It
anticipated the complete moving in a new building of the laboratory (250 persons), which will not be able to
perform experimental work from 25 july to mid November 2008. This period will be used to exploit
experimental results and write reports and publications, with the exceptions of 1 Ph D student going to URV
Tarragona for 2.5 months (WP14) and 1 Post Doc going to IRC Lyon for 3 months ( WP10).
About WP15 (Utilisation of activated carbon in adsorption processes) This WP has modifications in its
timesheet:
Task 15.1. Design and construction of an activated carbon fixed bed. This task initially planed to begin month
10 was asked to be delayed of 14 months in order to obtain enough results from Tasks 15.2 and 15.3 (static
adsorption tests on the different pollutants) for an efficient design of the dynamic adsorption system. Finally,
this task has begun 2 months in advance (month 22).
Task 15.2. Determination of the optimal contact time for adsorption of COD or ammonium wastewater with
batch tests. The beginning of this task has been delayed of 7 months and the duration was increased of 6
months partly because of the recruiting of the post doctoral researcher. Although the end is planed on month
33, major part of the results is achieved.



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Task 15.3. Determination of the optimal contact time for adsorption of dye and metal ion wastewater. This
task is in advanced of 5 months considering the initial scheduling, because it has been run in parallel with
Task 15.2 due to their similar approach. This task is achieved on time.
Task 15.4. Study of activated carbon adsorption process of COD. This task has been delayed of 4 months in
order to finalize results from task 15.2. The duration will be increased of 3 months and finished on month 36
so as to be run in parallel with Task 15.5 due to their similar approach.
Task 15.5. Study of activated carbon adsorption process of dyes and metal ions. This task is planed to begin
month 24 in advance of 2 months. The duration will be increased of 6 months and finished on month 36 so
as to be run in parallel with Task 15.4 due to their similar approach.
All tasks of WP16 are 100% completed. In any case, WP 16 offers to test sludge-based activated carbons in
biofilters out of its schedule as long as sludge-based activated carbon is provided in the next 6 months.
The WP17 (Management & co-ordination) has a delay of 2 months caused by the retard of sending of the
reports to the E.C.
The WP18 (Dissemination) has a delay of more or less 6 months in the task 18.1 REMOVALS newsletter, is
in time in the task 18.2 REMOVALS website but has to be improved constantly, is in time in the task 18.3.
Workshops and conferences and has a delay of 2 months in the task 18.4. Dissemination material.
About the whole project, the retard accumulated is about 37 months in a total of 493 months of work in all
workpackages. This represents a 7.5% of delay. This value is not very important as corrective measures
were taken in all workpackages.




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Table 5: Workpackages - Plan and Status Barchart
                                                                                                                                       24th month report

                                                                             1st year                                   2nd year                            3rd year
                                                         1   2   3   4   5    6    7    8   9   10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
WP1. Economical feasibility study
1.1. Individual economical feasibility studies
1.2. Integrated economical feasibility study
WP2. Reduction and stabilisation of the exce
2.1. Building-up of a bench-scale anaerobic dig
2.2. Fundamentals of thermophilic sludge stabil
2.3. Impact of the sludge pretreatment
2.4. Recovery of organic acids
2.5. Combination of pretreatment and thermoph
WP3. Sludge stabilisation in autothermal co
3.1. Building up of a bench-scale test plant and
3.2. Theoretical mixing study
3.3. Experimental mixing study
3.4. Detailed optimisation and feasibility aspect
WP4. Production of hydrogen from sludge
4.1. Determination of operating conditions
4.2. Evaluation of technical and economic feasi
4.3. Applicability of fermentation technology
WP5. Utilisation of enzymes from sludge in t
5.1. Extraction procedures
5.2. Experimental assays
5.3. Numerical prediction
5.4. Validation
5.5. Process optimisation
WP6. Gasification of sewage sludge
6.1: Characterisation of research objects
6.2: Influence of the pyrolysis extent on gasifica
6.3: Gasification reagent impact on the yield an
6.4: Identification of gasification kinetic models
WP7. roduction of organic substrate from sl
7.1 Evaluation of sludge disintegration methods
7.2. Optimization of chosen method with respec
7.3 Verification of enhancement of N and P rem
7.4 Optimization of process implementation in w
WP8. Advanced technology for the biologica
8.1. Evaluation of an activated sludge system fo
8.2 Evaluation of an airlift reactor for nitritation u
8.3 Comparison of activated sludge and airlift re
8.4. Evaluation of an activated sludge system fo
WP9. Minimisation of sludge production by
9.1. Plant set-up and start-up
9.2. Identification of most influential operation p
9.3. Sludge characterisation
9.4. Identification of suitable MBR sludge treatm
WP10. Destruction of organic compounds in
10.1. Influence of power ultrasound as pre-treat
10.2. Synthesis and characterization of catalyst
10.3. Operation in a continuous trickle bed reac
WP11. Excess sludge reduction by dewatera
11.1. Construction and installation of the pilot p
11.2. Operation of the industrial pilot plant unit
11.3. Optimisation of system
11.4. Economical and feasibility study
WP12. Production of activated carbon from
12.1. Identification of user requirements
12.2. Pilot plant for the production of sludge-bas
12.3. Production of SBA under known operating
12.4. Set-up and optimisation of new procedure
12.5. Characterisation of sludge-based adsorbe
12.6. Production of tailor-made SBA for differen
12.7. Final optimization of tailor-made SBA and
WP13. Utilisation of activated carbon as cata
13.1. Wet air oxidation operating with activated
13.2. Kinetic studies of model compounds and
13.3. Simulation studies of trickle-bed reactors;
13.4. Construction and installation of the indust
13.5. Industrial pilot plant tests
WP14. Utilisation of activated carbon as cata
14.1. Adsorption14.1. Adsorption
14.2. Oxidation. Active carbon behaviour
14.3. Complete modelling towards optimal cond
14.4. Construction and operation of the semi ind
14.5. Experimental validation of the optimal con
WP15. Utilisation of activated carbon in adso
15.1. Construction of a activated carbon fixed b
15.2. Determination of the optimal contact time
15.3. Determination of the optimal contact time
15.4. Study of AC adsorption process of COD a
15.5. Study of AC adsorption process of dye an
WP16. Utilisation of activated carbon in biof
16.1. Redesign and start-up of an existing biofil
16.2 Evaluation of biofilters’ performance param
16.3 Modelling of the biofiltration units
WP17. Management & co-ordination
17.1 Project management
17.2 Accessibility to project progression
17.3. Progress repports
WP18. DisseminationWP18. Dissemination
18.1 REMOVALS newsletter
18.2 REMOVALS website
18.3. Workshops and conferences
18.4. Dissemination material


                                                                                                                                       24th month report




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4. Short comments and information on co-ordination activities in the period, such as communication
   between partners, project meetings, possible co-operation with other projects/programmes etc…


The project co-ordination is achieved at two levels. The overall co-ordinator of the project is Prof. Azael
Fabregat. Prof. Fabregat is responsible of high level decisions and communications with E.C. and with the
Partners. The executive co-ordinator of the project is Dr. Christophe Bengoa. Dr Bengoa assumes regular
communication with E.C. as well as the day to day relations with the other Partners.
During second reporting period were organised two meetings, the 18th month meeting in Barcelona, 28-29
January 2008, and the 24th month meeting in Lodz, 30 June and 01 July 2008.
P1 Universitat Rovira i Virgili, P6 Gestio Ambiental i Abastament, S.A. and P7 Tratamientos y
Recuperaciones Industriales, S.A. met on a regular basis for the WP2, WP3 and WP5. Dr. Debora Nabarlatz
Post-Doctoral researcher from P1 Universitat Rovira I Virgili made the stage during 1 month in Prague,
working on enzyme extraction for the WP5.
P3 Universitat Autonoma de Barcelona was the organizer of the 18th month Coordination Meeting during 28-
29 January 2008 in Barcelona (Spain). For the WP8, two meetings were realised between P3 and P8 in
Barcelona and Lodz. A PhD student from Prague (Jana Vondrysova) made a stage during 1 month in
Barcelona, working on WP8. On the other hand, P3 and P13 made an application for a Picasso Action
Project (French and Spanish Governments) for the next year.
P4 University of Glamorgan. Potential links with the following partners have been identified during this
reporting period.
•     Imperial College, London U.K (ICL). UOG has agreed to supply effluent from its hydrogen bio-reactor
      in a dried form. The material will be analysed by UOG with regards to total solids, volatile solids,
      carbohydrate, and volatile fatty acid content. This material will be evaluated by Imperial College as a
      candidate for the production of activated carbon.
•     Universitat Rovira i Virgili, Spain (URV). UOG has agreed to supply effluent from its hydrogen bio-
      reactor in a liquid form. The material will be analysed by UOG with regards to total solids, volatile
      solids, carbohydrate, and volatile fatty acid content. The material will contain extraneous enzymes
      added during pre-treatment. URV will evaluate the feasibility of recovering these enzymes thus
      reducing the cost of pre-treatment.
P5 Institut National Polytechnique de Toulouse as the leader of WP14 actively participated to the definition of
convenient sludge based activated carbon - to be prepared by WP 12 - for adsorption, oxidation and more
precisely for being used in AD-OX process. A special meeting of WP 12, 13, 14 and 15 was held in Lodz in
addition to the 24th month meeting. Close contacts are maintained with WP13 concerning oxidation with
SBAC (H. Delmas visit to Tarragona and common meeting at Lodz). This collaboration will continue with the
2.5 month visit at URV Tarragona of C. Ayral, Ph D Student at INP Toulouse. P5 intensely interacted with
P13 in WP10. Rana Kidak, INP post Doc has yet been 2 times at IRC Lyon and will work there for 3 month
during the LGC-INP laboratory moving. Conversely INP received F. Di Greggorio for short term visit.
P8 Institute of Chemical Technology Prague. Potential links with the following partners have been identified
during this reporting period.
•     For the WP7 four quarterly meetings were realised between P8 Institute of Chemical Technology
      Prague and P18 K&H Kinetic in Prague.
•     For the WP7 and simultaneously for the WP9 meeting was realised between partners P8 Institute of
      Chemical Technology Prague and P10 Technische Universität Berlin in Berlin.
•     For the WP8 meeting was realised between partners P3 Universitat Autonoma de Barcelona and P8
      Institute of Chemical Technology Prague in Barcelona.
•     Post-Doctoral researcher from P1 Universitat Rovira I Virgili (Debora Nabarlatz), made the stage
      during 1 month in Prague, working on WP5.
•     Doctoral researcher from P8 - ICT (Jana Vondrysova), made the stage during 1 month in Barcelona
      (P3), working on WP8.
P10 Technische Universität Berlin. For the WP9, meetings between P8 and P10 were realised on the 1st July
2007 in Prague and on the 8th April 2008 in Berlin. Besides the discussion of results sludge samples were
exchanged.


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P13 CNRS, Institut de Recherches sur la Catalyse, Lyon. The post-doctoral student at CNRS in Lyon
(François Di Gregorio) went twice to INP Toulouse (in October 2007 and April 2008) to perform the
sonication treatment on the sewage sludges used for further Catalytic Wet Air Oxidation. The post-doctoral
student in INP Toulouse (Rana Kidak) spent one week at CNRS Lyon (June 23-27, 2008) to learn about the
WAO treatment of sludges. She will spend three months from September 2008 in CNRS to perform the
catalytic continuous experiments on the trickle-bed reactor.

P14 Imperial College of Science, Technology & Medicine. Dr. Maretva Baricot, from P1 URV, came to P14
ICL to spend one month working on activated carbon production. Dr. Geoff Fowler from P14 ICL went to
URV P1 to participate in the examination of the PhD candidature of Dr. Maretva Baricot. In October 2007,
P14 ICL hosted a two day meeting in London between themselves and P2 GPA. Moreover, in December
2007, ICL hosted a one day meeting in London between themselves and P16 CCC. Both meetings were
held to strengthen links and to maximise collaboration between the respective WP 12 partners. However, in
the case of the meeting with GPA, due to the departure of their post-doc assigned to WP 12, soon after the
meeting, the planned collaborative activities arising from the meeting have had to be scaled down. However,
in August/September of this year (2008), a new post-doc will assume the currently vacant position, enabling
the recommencement of joint activities. The meeting between P14 ICL and P16 CCC formed the foundation
of a highly fruitful relationship between these two partners, of which the primary outcomes thus far include:
the characterisation by P16 CCC of SBAs produced by P14 ICL; the provision by P16 CCC of commercial
carbons for use by P14 ICL as reference carbons in key WWT applications; the large-scale production, by
P16 CCC and under regimes prescribed by P14 ICL, of SBAs from sludges provided by P14 ICL. Extensive
electronic communication has occurred between P14 ICL and P1 URV (particularly with Dr. Frank Stüber);
the subject of these emails has primarily been the performance of the SBAs sent by P14 ICL to P1 URV and
the requirements of P1 URV as regards the further provision of SBAs. Emails on the same themes have
also been exchanged between P14 ICL and respectively, P2 GPA, P5 IPL and P3 UAB. Further emails have
been exchanged between P14 ICL and P1 URV on the subject of the drafting of a joint paper; this paper is
currently in production. Emails were also exchanged between P14 ICL and P2 GPA on the writing of a joint
conference paper and a conference poster; both tasks were successfully completed. Emails have been
exchanged between P14 ICL and P9 TUL on, firstly, the provision by P9 TUL of dried sewage sludge
samples for use by P14 ICL in SBA production; the outcome of these communications has been that ICL
now has three TUL-sourced sludges in their possession. The second item discussed was the TGA-MS
analysis by P9 TUL of SBAs supplied by P14 ICL. Again, the outcomes were positive: P9 TUL has analysed
                                                                                                   nd
the samples they received from P14 ICL and the results were conveyed to P14 ICL at the 2 annual
REMOVALS progress meeting (in Łodz). P14 ICL will host, in London, the 30 month REMOVALS progress
meeting, with support from P16 CCC.
No co-operation with other projects was scheduled during the first reporting period.




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Section 4 – Other issues.

Not applicable for this project.




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Annex – Plan for using and disseminating the knowledge.


1.    Section 1 - Exploitable knowledge and its Use.
Overview table.

  Exploitable         Exploitable                                                            Owner & Other
                                       Sector(s) of      Timetable for    Patents or other
  Knowledge          product(s) or                                                             Partner(s)
                                       application      commercial use     IPR protection
  (description)       measure(s)                                                                involved
Use of internal     Decision making Wastewater         2009 (non          No.                ICT (Owner),
organic             guide for use of treatment         commercial                            KHK, URV and
substrate for       internal organic industry.         use).                                 TUB.
improvement of      substrate.
wastewater
treatment.
High surface        BET surface       Waste water      None.              None planned.      GPA and ICL
area, physically    area (measure).   and gas                                                (owners).
activated SBAs.                       treatment.
Use of              The use of a      Wastewater       2009 (non          No.                UOG
cellulolytic        commercially      treatment        commercial                            (Biocatalysts,
enzyme for          available         industry.        use).                                 Pontypridd, UK)
improving           enzyme to
sludge rheology     improve sludge
and digestibility   digestion.
Application of      Automatic        Wastewater        2010.              No.                UAB (Owner).
partial             control loop     treatment
nitrification       based on in-line industry.
process for         OUR
improving the       measurement
reject water        applied in an
treatment.          activated sludge
                    system with
                    three-reactors.

Use of internal organic substrate for improvement of wastewater treatment. Exploitable result
represents innovation of wastewater treatment technology. The Partners involved in this exploitable
knowledge are the Partners working in Workpackage 7 (Production of organic substrate from sludge for
enhancement of nutrient removal), ICT (responsible), KHK, URV, TUB (collaborators). The result can be
exploited by wastewater treatment designers and operators, however it is not suitable for commercial use.
There is necessary further research during next years for optimising the desired result. The result is not
suitable for patenting. Other potential impact of modified technology is reduction of biological excess sludge
production at wastewater treatment.
High surface area, physically activated SBAs. The finding is that, when coupled with HCl rinsing (a de-
ashing technique), it is feasible to use physical activation methods to produce SBAs with relatively high
porosities and BET surface areas. Traditionally, the use of physical activation to produce high surface area
adsorbents from sewage sludge has been hindered by sewage sludge’s high inorganic (ash) content; ash
has a negligible porosity and as the physical activation develops porosity through the partial burn-off of the
                                                                                                          2 -1
sludge’s carbonaceous fraction, researchers have failed to attain BET surface areas in excess of 250 m g
from sewage sludge - the highest reported BET surface area for a SBA prepared by physical activation is
226 m2 g-1, which was attained by Rio et al. (2006a, 2006b) using steam as the reagent. Fitzmorris et al.,
(2006) also studied the washing with HCl of a SBA prepared by physical activation, but the BET surface area
of the resulting material was only 143 m2 g-1. This project has achieved BET surface areas in excess of 600
m2 g-1 – the highest is 622 m2 g-1 - by washing sewage sludge that firstly had been carbonised at 600°C for
1 h and secondly was activated with CO2 at 900°C for 2 h in a 4 M solution of HCl. The carbonisation and
activation conditions have yet to be optimised, suggesting that further improvements in the porosity are
feasible. The primary partner responsible for this work was Partner 2 – GPA – although partner 14 – ICL –
made a contribution by suggesting HCl washing might be an effective means of beneficiating physically


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activated SBAs. At present it is unclear how this development could be exploited, particularly as the
adsorptive properties of the SBAs have yet to be assessed. With regard to the novel value of this finding, the
use of acid washing to de-ash activated carbons and activated carbon pre-cursors has been reported
extensively in the literature. However, the work has generally favoured the use of de-ashing reagents other
than HCl; where HCl was used, it was usually been used in tandem with hydrofluoric acid (HF). The key
barrier to commercialisation of this idea is the high cost of rinsing in HCl, especially at high concentrations.
However, research conducted at ICL has indicated that the use of lower concentrations of HCl should not
significantly inhibit the efficacy of the de-ashing process. A further problem pertains to how the waste
products generated by this process can be disposed of: potentially they pose a high risk to the environment
and the cost of their disposal could therefore prove to be exorbitant. No work has been conducted yet into
the investigation of the feasibility of commercialising this SBA production method; until it has been
ascertained that there are no other findings arising from this project which are more commercially
exploitable, work on commercialising the method is to be suspended. However, this stance may alter if the
carbons produced by this method are found to exhibit exceptional pollutant removal properties.
Use of cellulolytic enzyme for improving sludge digestibility and rheology. During this investigation
enzymatic saccharification was identified as a pre-treatment option for primary sewage biosolids (PSB). This
enzyme breaks down complex polysaccharides in the PSB allowing fermentative hydrogen production to
take place (Massanet-Nicolau, 2008; Massanet-Nicolau et al., 2008). The saccharification process could be
used in a conventional methanogenic digester to improve digestibility. In addition the enzymatic
saccharification also causes significant improvement in rheology of the PSB making it easier to pump. This
could result in operational savings if deployed in a full scale sewage treatment process. Since the enzyme is
a commercial product, designed to be used at full scale, its cost is lower than that of cellulolytic enzymes of
research grade. At present the cost of pre-treating a litre of PSB is 3.25 UK pence. The process is not yet
suitable for commercial use and would require more specific pricing information based on the economies
offered by deployment at full scale in the wastewater treatment process, as well as an evaluation of the cost
benefits derived from improving the rheology of sewage biosolids. Massanet-Nicolau, J., Dinsdale, R., and
Guwy, A. 2008 Hydrogen production from sewage sludge using mixed microflora inoculum: Effect of pH and
enzymatic pretreatment. Bioresource Technology. Massanet-Nicolau, J. 2008 “Fermentative hydrogen
production from sewage sludge” in Hammamet, Tunisia.
Application of partial nitrification process for improving the reject water treatment. Exploitable result
represents innovation of reject water treatment technology. The Owner of this exploitable knowledge is the
leader of the Workpackage 8 (P3, UAB). The result could be exploited by wastewater treatment designers
and operators in the next years. There is necessary further research during next year for optimising the
desired result and coupling with denitrification process. The result is not suitable for patenting.




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2.      Section 2 – Dissemination of knowledge.
2.1.    Overview table.

                                                                                                Partner
  Planned /                               Type of              Countries       Size of
                          Type                                                               responsible /
 actual Dates                            audience              addressed      audience
                                                                                               involved
12-07-2006 (1)     Presentation       Industry and       France.           > 100            UOG
                                      research.
06-03-2007 (2)     Project website    General public.    All.              Impossible to    URV
                                                                           determine.       (responsible), all
                                                                                            other Partners
                                                                                            (involved).
24-04-2007 (3)     Poster             Industry and       All.              > 100            URV
                                      research.
02-07-2007 (4)     Exhibition         Industry and       Czech Republic    < 20             ICT and KHK
                                      research.          and Slovak                         (responsibles),
                                                         Republic.                          all other
                                                                                            Partners
                                                                                            involved.
13-07-2007 (5)     Presentation       Higher             United Kingdom. > 100              UOG
                                      education.
15-07-2007 (6)     Conference         Industry and       All.              > 200            URV and GPA
                                      research.
24-07-2007 (7)     Poster             Higher             Germany.          < 100            TUB
                                      education.
25-07-2007 (8)     Exhibition         Industry.          Spain.            < 20             TRI and URV
                                                                                            (responsibles),
                                                                                            UAB and EDA
                                                                                            (assisted), all
                                                                                            other Partners
                                                                                            (involved).
01-09-2007 (9)     Poster             Higher             Australia.        > 100            UOG
                                      education.
19-09-2007 (10)    Information        Research           Czech Republic. 200                ICT
                   lecture in the
                   conference
19-09-2007 (11)    Publication in     Research           Czech Republic. 200                ICT
                   proceedings of
                   conference
05-10-2007 (12)    Poster             Industry and       France.           > 100            URV
                                      research.
17-10-2007 (13)    Presentation       Industry           United Kingdom. > 100              UOG
5-11-2007 (14)     Conference         Research           All               200              TUB
                   including
                   publication
2007 (15)          Presentation                          Japan.                             UOG
       (16)
2007               Article in trade   Industry           All.                               UOG
                   Journal
12-03-2008 (17)    Poster             Higher             Czech & Slovak    230              ICT
                                      education          Republics.



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17-03-2008 (18)     Presentation                      India                              UOG
20-05-2008 (19)     Exhibition     Industry public    Czech & Slovak   21                ICT and KHK
                                   administration     Republics.
25-05-2008 (20)     Article        Industry and       All.                               UOG
                                   Higher
                                   Education
26-05-2008 (21)     Conference     Higher             All.             150               ICT
                                   education
26-05-2008 (22)     Conference     Industry and       Tunisia.         300+              UOG
                    Paper          Higher
                                   Education
01-06-2008 (23)     Poster         Industry and       All.             > 200             URV and GPA
                                   research.
01-06-2008 (24)     Conference     Research           International    200               INP
                                                                                         (responsible)
                                                                                         and CNRS
02-06-2008 (25)     Conference     Industry and       All.             > 50              URV
                                   research.
03-06-2008 (26)     Conference     Research and       International.   To be             GPA and ICL
                                   waste industry.                     determined.
03-06-2008 (27)     Conference     Research           International    200               CNRS
             (28)
18-06-2008          Conference     Research           All              30                TUB
             (29)
14-06-2009          Conference     Industry and       All.             > 100             URV
                                   research.
14-06-2009 (30)     Conference     Industry and       All.             >200.             URV
                                   research.                                             (responsibe)
24-06-2008 (31)     Conference     Research           All              >500              TUB
                    including
                    publication
24-06-2008 (32)     Conference     Research           International    200               GPA
             (33)
30-06-2008          Conference     Industry and       UK               < 100             ICL
                                   research.
01-07-2008 (34)     Seminar and    Industry and       Poland.          > 20              TUL and STL
                    exhibition     research.                                             (responsibles),
                                                                                         all other
                                                                                         Partners
                                                                                         involved.
10-07-2008 (35)     Presentation   Industry.          United Kingdom.                    UOG
12-07-2008 (36)     Conference     Research           All             >1000              TUB
                    including
                    publication
13-07-2008 (37)     Conference     Research           International    1000              CNRS
                                                                                         (responsible)
                                                                                         and INP
24-08-2008 (38)     Conference.    Industry and       All.             > 200             URV
                                   research.
01-09-2008 (39)     Conference.    Research and       International.   < 1000            ICL
                                   waste industry.



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7-09-2008 (40)        Conference             Research               All                     3000                   TUB
19-09-2008 (41)       Conference             Research               All                     100                    TUB
              (42)
21-09-2008            Publication in         Research               International           To be                  UAB
                      Proceedings of                                                        determined
                      Conference
21-09-2008 (43)       Publication in         Research               International           To be                  UAB
                      Proceedings of                                                        determined
                      Conference
08-10-2008 (44)       Publication in         Research               International           To be                  UAB
                      Proceedings of                                                        determined
                      Conference
21-10-2008 (45)       Poster.                Industry and           Mediterranean           < 100                  URV
                                             research.              Countries.
21-10-2008 (46)       Poster.                Industry and           Mediterranean           < 100                  URV
                                             research.              Countries.
21-10-2008 (47)       Poster.                Industry and           Mediterranean           < 100                  URV
                                             research.              Countries.
2009 (48)             Paper                  Industry and           All.                    Impossible to          URV and ICL
                                             research.                                      determine.             (both
                                                                                                                   responsible)

(1)    Bioydrogen Production Research in the UK. International Energy Association (IEA-HIA Annex 21), World Hydrogen Energy
       Conference, Lyon Congress Centre, Lyon, France. July 12th, 2006. Guwy A.J.
(2)    http://www.etseq.urv.es/REMOVALS/index.html.
(3)    A poster entitled “Enzymatic elimination of phenol: pH influence” was performed to the 1st International Congress on Green
       Process Engineering, which has been held in Toulouse (France), 2007. Pramparo, L.; Castro, U.I.; Stüber, F.; Font, J.; Fortuny,
       A.; Fabregat, A.; Bengoa, C.
                                                                                                       st
(4)    A poster presentation of the project was conducted in Prague (Czech Republic) during the 1 annual meeting. Each Partner
       presented two posters, the first with a description of its organisation, the second one with a description of the tasks where they
       are involved. The assistance were: Faculty of chemical and food Technol. Bratislava, Slovakia, Veolia Voda a.s., Czech
       Republic, Cero VVV T.G.M., Prague, Czech Republic, Hydroprojekt, Č1ŽP, Czech Republic, Vodohosp. Ponila Pler, Czech
       Republic, VUT, Brně, Czech Republic.
(5)    Sustainable Solutions for Energy Production and Waste Treatment. 13th July 2007. Cranfield University. Dr Richard Dinsdale.
(6)    CARBON 2007 CONFERENCE, July 15 - 20, 2007, Seattle, USA. Activated carbon used as catalyst for the catalytic wet air
       oxidation of phenol. Maretva Baricot (URV), Seyed A. Dastgheib (URV), Agustí Fortuny (URV), Frank Stüber (URV), Christophe
       Bengoa (URV), Azael Fabregat (URV), Laurence Le Coq (GPA), Josep Font (URV).
(7)    Schaller, J.; Drews, A.; Kraume, M.: Minimisation of Sludge Production by Utilisation of the Biological Potential in Membrane
       Bioreactors, BASF Summer Course, Ludwigshafen 23 July - 2 August 2007.
(8)    A poster presentation of the project was conducted in Tarragona. The four Spanish Partners directed the meeting. Each Partner
       involved, presented two posters, the first with a description of its organisation, the second one with a description of the tasks
       where they are involved. The attendants were: SIRUSA (Urban wastes incineration), ERCROS (Chemical industry), GRECAT
       (Catalan governamental organisation), IQA (Chemical industry), CLARIANT (Chemical industry), CATOR (Wastewater
       treatment industry).
(9)    A poster entitled “The Anaerobic Fermentative Production of Hydrogen from Sewage Sludge” is being presented at the 11th
       IWA Specialist Conference on Anaerobic Digestion on September 2007 in Brisbane, Australia.
(10)   Jeníček P., Vondrysová J., Pokorná D.: Reduction, modification and valorisation of sludge, 7th International conference
       Wastewater 2007, 18.-20.9.2007, Brno, pp 69-73 (in Czech).
(11)   Vondrysová J., Slámová K., Koubová J., Jeníček P.: Comparison of different disintegration methods of activated sludge for
       releasing organic substrate for denitrification, 7th International conference Wastewater 2007, 18.-20.9.2007, Brno, pp 139-143
       (in Czech).
(12)   A poster entitled “Determination of the kinetic model and parameters of the enzymatic elimination of phenol in a torus reactor”
       was performed to the 11e Congrès de la Société Française de Génie de Procédés (SFGP), Saint Etienne (France), 2007.
       Pramparo, L.; Stüber, F.; Font, J.; Fortuny, A.; Fabregat, A.; Bengoa, C.
(13)   Hydrogen Energy Progress in Wales. 17th Oct 2007. Angel Hotel Cardiff. Dennis Hawkes, Jon Maddy.
(14)   Kraume, M.; Wedi, D.; Schaller, J.; Iversen, V.; Drews, A.: Fouling in MBR – What use are lab investigations for full scale
       operation?, Proc. IMSTEC07, Sydney 5-9 Nov 2007, 291.



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(15)   Hydrogen Energy and Fuel Cell Activities in Wales. Renewable energy 2007 International Exhibition & Conference. Makuhari
       Messe, Chiba, Japan. Jon Maddy.
(16)   Improving the treatment of sewage sludge. 2007. Water and sewerage journal. 4 p25. Richard Dinsdale.
(17)   Vondrysová J., Koubová J., Jeníček P.: Using of activated sludge and primary sludge as a organic substrate for denitrification,
       Kaly a odpady 2008, 12.-13.3.2008, Bratislava, pp 50-58 (in Czech).
                                                                               th         th
(18)   Hydrogen Research and Development The UK perspective. March 17 -18 , 2008. Low Carbon Technologies for Decentralised
       Power Production-An Indo-UK Workshop. Indian Institute of Technology Madras (IITM), India. Professor Alan Guwy.
(19)   Presentation of the project was conducted in Prague (Czech Republic) consisted of the first lecture with a description of project
       organisation, the second one with a description of each task. The participants represented: Šumavské vodovody a kanalizace,
       Veolia Voda a.s., Vodohosp. Podnik Plzeň, Povodí Vltavy, Technické služby Hostivice, ENVI-PUR Soběslav, Vodovody a
       kanalizace Vsetín,. ČIŽP - Olomouc, - Liberec, - Ústí nad Labem, Bohemiaplan, TPCA Kolín, .1.JVS České Budějovice, Krajský
       úřad Plzeň, EPS.
                                                                                th
(20)   Fermentative hydrogen production from sewage sludge. 25-05-2008. V International symposium on anaerobic digestion of solid
       wastes and energy crops.
(21)   Vondrysová J., Jeníček P.: Comparison of activated sludge from membrane biological reactor and conventional system -
                                                             th
       biodegradability and pretreatment by disintegration, 5 International Symposium on Anaerobic Digestion of Solid Waste and
       Energy Crops, 25.-28.5.2008, Hammamet, Tunisia, CD.
(22)   Hydrogen production from sewage sludge using mixed microflora inoculum: Effect of pH and enzymatic pre-treatment. 2008.
       Bioresource Technology, Elsevier. Massanet-Nicolau, J.; Dinsdale, R. & Guwy, A.
                                                                                                                                         th
(23)   A poster entitled “Numerical approach for the enzymatic elimination of phenol in a torus reactor” has been submitted to the 18
       European Symposium on Computer Aided Process Engineering (ESCAPE-18), Lyon (France), 2008. Pramparo, L.; Pruvost, J.;
       Stüber, F.; Font, J.; Fortuny, A.; Fabregat, A.; Legentilhomme, P.; Legrand, J.; Bengoa, C.
                                nd
(24)   Poster presentation at 2 International Conference on Engineering for Waste Valorisation, in Patras, Greece, entitled “On the
       elimination of sewage sludges via Catalytic Wet Air Oxidation.”, M. Bernardi, F. Di Gregorio, C. Descorme and M. Besson.
       Results of WP10 were presented together with other results of P13.
                                                                                                                            th
(25)   An oral presentation entitled “Extraction of enzymes from activated sludge” was performed at WIT 2008, 4 International
       Conference on Waste Management 2008 – Waste Management and the Environment, which was held at Granada, Spain, 2-4
       June 2008. The final manuscript was published in the proceedings of the conference: Nabarlatz, D.; Vondrysova, J.; Jenicek, P.;
       Stüber, F.; Font, J.; Fortuny, A.; Fabregat, A.; Bengoa, C. “Extraction of enzymes from activated sludge”, Waste Management
       and the Environment IV, WIT Transactions on Ecology and the Environment, Vol. 109, pages 249 – 257 (2008). The paper
       describes the work conducted in recovery of enzymes by disintegration of sludge using magnetical stirring, mechanical and
       ultrasound disintegration for the experiments carried out during the research stay in Prague, Czech Republic.
(26)   An abstract entitled ‘Re-use of sludge activated carbon production for industrial waste water treatment’ has been submitted to
       the 2nd International Conference on Engineering for Waste Valorisation, which is to be held at the Convention Centre,
       University of Patras, Greece on June 3-5, 2008 (http://www.wasteeng08.org). The abstract was submitted on the 16th of July,
       2007 and describes the work conducted in the production of SBAs via carbonisation, physical activation and de-ashing.
                               th
(27)   Oral presentation at 11 Meeting of the European Society of Sonochemistry, in La Grande Motte, France, entitled “Ultrasonic
       pre-treatment of waste activated sludge and its effect on catalytic wet air oxidation”, R. Kidak, B. Ratsimba, A.M. Wilhelm, F. Di
       Gregorio, C. Descorme, M. Besson. Results of WP10 were presented.
(28)   Drews, A.; de la Torre, T.; Iversen, V.; Schaller, J.; Stüber, J.; Meng, F.; Lesjean, B.; Kraume, M.: Is there a compelling fouling
       indicator? - A critical evaluation of various MBR fouling characterisation methods, 2nd Oxford and Nottingham Water and
       Membranes Research Event, Oxford 18-20 June 2008.
(29)   An oral presentation entitled “Evaluation of sludge-based activated carbon as packing material in biofiltration in comparison to
       classical materials” is accepted for the 3rd IWA Odour and VOCs conference: Measurement, Regulation and Control
       Techniques to be held from October 2008 in Barcelona, Spain.
                                                                         nd
(30)   An oral presentation is planned to be performed at GPE 2009, 2 International Congress on Green Process Engineering, which
                                                                                                   th
       will be held at Venice, Italy, 14-17 June 2009. The deadline for abstract submission is 10 September, 2008. Nabarlatz, D.;
       Stüber, F.; Font, J.; Fortuny, A.; Fabregat, A.; Bengoa, C. “Extraction and purification of hydrolytic enzymes from activated
       sludge”.
(31)   Schaller, J.; Camacho, M.; Drews, A.; Kraume, M.: Operation of Different Membrane Bioreactors at High Sludge Ages for
       Minimising Excess Sludge Production, SIDISA, Florence 24-27 June 2008.
(32)   Gerente C., Guiheneuf L. and Le Coq L. Chemical characterization of Sludge Based Adsorbents (SBA) and Comparison with
       commercial activated carbons. International Symposium on Sanitary and Environmental Engineering, Florence, Italy, June 24-
       27, 2008.
(33)   A poster entitled "Brown Gold: Turning sewage sludge into activated carbon" was presented at the fifth annual Resource
       Efficiency KTN and WARMNET “Tackling Waste - Decoupling Growth from Environmental Impact” Conference on June 30-July-
       1, 2008, Nottingham (UK). The poster won first prize in the conference’s BIFFA sponsored, poster competition.
                                                                                                          nd
(34)   A poster and oral presentation of the project were conducted in Lodz (Poland) during the 2 annual meeting. During the
       seminar each Partner presented its organisation and the objectives and tasks of all workpackages it is responsible for. Each
       partner presented also two posters, the first with a description of its organization, the second one with the description of results
       obtained in each workpackage.
                                                                                     th
(35)   The sustainable production and utilisation of hydrogen from waste. 10 July 2008. Energy from Waste in Wales. All Nations
       Centre, Cardiff. Dr Richard Dinsdale.



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(36)   Kraume, M.; Wedi, D.; de la Torre, T.; Schaller, J.; Iversen, V.; Drews, A.: Scale-up of Lab Investigations on Fouling in MBR –
       Potentials and Limitations, ICOM 2008, Honolulu 12-18 July 2008.
                                   th
(37)   Poster presentation at 14 International Congress on Catalysis, in Séoul, Korea, entitled “Efficiency of soluble and
       heterogeneous catalysts in the Catalytic Wet Air Oxidation of sewage sludge”, M. Bernardi, M. Besson, C. Descorme, F. Di
       Gregorio, S. Deleris, A. Sourzat, R. Kidak, B. Ratsimba, A.M. Wilhelm. Different results on CWAO of sludges, including WP10.
(38)   An oral presentation entitled “Extraction of protease and lipase from activated sludge by ultrasound and magnetic stirring
                                                            th
       disintegration” will be performed at CHISA 2008, 18 International Congress of Chemical and Process Engineering, which is to
                                                                                                              th
       be held at Prague, Czech Republic, 24-28 August 2008. The final manuscript was submitted on the 15 June (2008) and
       describes a comparison of the work conducted in extraction of enzymes of sludge by magnetic stirring disintegration and
       ultrasound disintegration for the experiments carried out using sludge from WWTP Reus and from WWTP Prague.
(39)   A poster and a paper entitled ‘Influence of source and treatment method on the properties of activated carbons produced from
       sewage sludge’ have both been accepted for the forthcoming ‘European Conference on Sludge Management’ conference in
       Liege, Belgium on September 1-2, 2008 (http://www2.ulg.ac.be/bioreact/ECSM08).
(40)   Schaller, J.; Iversen, V.; Drews, A.; Kraume, M.: Operation of Membrane Bioreactors in parallel: Experiences and Difficulties,
       World Water Congress 2008, Vienna 7-12 September 2008.
(41)   Schaller, J.: Minimisation of Excess Sludge Production in Membrane Bioreactors, Network Young Membrains, Berlin 18-19
       September 2008.
(42)   An oral presentation entitled “Start-up of a biofilm airlift system to obtain partial nitrification of a high-strength ammonium
       wastewater” is accepted for the Third International Meeting on Environmental Biotechnology and Engineering (3IMEBE) to be
       held from September 2008 in Palma de Mallorca, Spain.
(43)   An oral presentation entitled “Kinetic models for ammonium oxidising bacteria inhibition by free ammonia and free nitrous acid”
       is accepted for the Third International Meeting on Environmental Biotechnology and Engineering (3IMEBE) to be held from
       September 2008 in Palma de Mallorca, Spain.
(44)   An oral presentation entitled “Kinetic models for ammonium oxidising bacteria inhibition by free ammonia and free nitrous acid”
       is accepted for the Third International Meeting on Environmental Biotechnology and Engineering (3IMEBE) to be held from
       September 2008 in Palma de Mallorca, Spain.
                                                                                                                      th
(45)   A poster entitled “Modeling the enzymatic elimination of phenol with CFD” has been submitted to the 11 Mediterranean
       Congress of Chemical Engineering, which is to be held at the Fira of Barcelona, Barcelona, October 21-24, 2008.
                                                                                                                      th
(46)   A poster entitled “Extraction of protease and lipase from activated sludge” has been submitted to the 11 Mediterranean
       Congress of Chemical Engineering, which is to be held at the Fira of Barcelona, Barcelona, October 21-24, 2008. The abstract
                                  th
       was submitted on the 27 June (2008) and describes the work conducted in the extraction of enzymes of sludge by magnetic
       stirring disintegration and ultrasound disintegration for the experiments carried out using sludge from WWTP Reus.
(47)   An abstract entitled ‘Sludge based activated carbon for the catalytic wet air oxidation of phenolic wastewater’ will be submitted
       to the 2nd International Congress on Green Process Engineering, which is to be held in Venice, Italy on June 14-17, 2009
       (http://www.GPE-EPIC2009.org).
(48)   A paper entitled “Preparation of sludge based active carbons and its application in catalytic wet air oxidation of phenol” is
       currently in preparation between URV and ICL and will be presented either to Carbon, Applied Catalysis B: Environmental or
       Journal of Hazardous Materials.




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REMOVALS, FP6-018525                                                 Periodic Activity Report


3. Section 3 - Publishable results.
The consortium is not ready to publicise in this reporting period.




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