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					                            Yearly average emission and consumption levels associated with the use of BAT for non
                            integrated uncoated fine paper mills, non integrated coated fine paper mills and non
Table 6.31                  integrated tissue mills.

                                                                                   1                         2
Parameter                   Units                        Uncoated fine paper           Coated fine paper
BOD 5                       kg/t of paper                0,15-0,25                     0,15-0,25
COD                         kg/t of paper                0,5-2                         0,5-1,5
TSS                         kg/t of paper                0,2-0,4                       0,2-0,4
AOX                         kg/t of paper                <0.005                        <0.005
Total P                     kg/t of paper                0.003-0.01                    0.003-0.01
                                                                   5
Total N                     kg/t of paper                0.05-0.2                      0.05-0.2
                                                                 6
Wastewater Amount           m3/t paper                   10-15                         10-15
notes:
1) The fibre furnish might be e.g. 100% bleached kraft pulp and fillers and sizes might amount to 15-30%. For mass sized paper
the upper ranges for COD and BOD have to be considered
2) The fibre furnish might be e.g. 100% bleached kraft pulp and fillers coating colour might amount to 20-40%. Upgrading of paper
colours consist of both surface sizing and application of coating
3) Fibre furnish 100% purchased chemical pulp. For tissue manufactured of a fibre mix of recycled and virgin fibre, see also
chapter 5.4.2
4) The higher AOX value can be caused by wet strength agents that contain chlorinated organic substances
5) For coloured grades the nitrogen releases can be higher when N-containing azo dyestuffs are used
6) For mills which are producing coloured or strong coloured grades fresh water consumption can normally bit be bought
below 17 m3/t
7) A change of basis weight and speed of the paper machine have a significant effect on the specific water
consumption (SWC). Lower basis weights (down to 12 g/m2) and lower speeds corresponds to higher SWC.




BOD


In well designed treatment plants BOD5 is removed almost completely (95% + removal) from paper mill waste water when the carbon-
phosphorus-nitrogen ratio and oxygen supply is maintained sufficient and well controlled. In case of disturbance or if some of the running
parameters are moving away from the target level the BOD5 concentration in effluents will start to increase. This calls for adjustment of the
running parameters and/or analysis of the biomass. BOD5 levels will usually be below 25 mg BOD5 / l and can reach values down to 5 mg/l
(almost completely removal). However, BOD5 levels around 5 mg/l are hardly to measure accurately and reproducible. Depending on the
water flow this correspond to 0,15 kg BOD5 /t (at 10mg/l and 15m3 flow/t) and 25 kg BOD5 / t respectively (at 25 mg/l and 10m3 flow).


COD
Depending on the paper grade manufactured, the applied techniques for prevention and control of emissions and the water flow per tonne of
product, the wastewater from paper mills after treatment contains between 50-150 mg COD / l.


TSS
Under normal operation conditions, the water from the secondary clarifier is fairly clear.
The content of suspended solids is in the range of below 20 to 30 mg/l. This corresponds to
discharges of 0.2 - 0.4 kg TSS/t. The values depend on the surface load of the secondary
clarifier and the characteristics of the biomass. With bio filtration also lower concentrations are normally achievable.


AOX
Nowadays, discharges of chlorinated organics are very low as the purchased pulp used in non-integrated paper mills is normally either ECF
or TCF bleached pulp. Activated sludge treatment result in a further AOX reduction between 30 and 50%. However, this reduction is partly
achieved by stripping of these compounds during wastewater treatment. Depending on the purchased pulp and chemical additives used
paper mills discharge chlorinated organic compounds below 0,005 kg/t.
N AND P
Mineral nutrients are usually added to the biological treatment plant to keep the
balance C : P : N which is of crucial importance for the growth of active biomass. To find and
keep a balance between biodegradable carbon, nitrogen- and phosphorus-compounds a certain
fine-tuning of the added nutrient feed is required. Usually, phosphorus is added as phosphorus
acid and nitrogen in form of urea. When the system is well optimised nutrients discharge well
below 1 mg tot-P/l and 5 mg total N/l are achievable. The corresponding loads are 0.003-0.001 kg
P/t and 0.05-0.2 kg N/t respectively.
 ls associated with the use of BAT for non
 rated coated fine paper mills and non


                                                  3
                                         Tissue
                                         0,15-0,4
                                          0,4-1,5
                                          0,2-0,4
                                         <0.01 4
                                       0,003-0,015
                                        0,05-0,25
                                         10-25 7

 ht amount to 15-30%. For mass sized paper


  might amount to 20-40%. Upgrading of paper


mix of recycled and virgin fibre, see also




 sumption can normally bit be bought




val) from paper mill waste water when the carbon-
olled. In case of disturbance or if some of the running
 ts will start to increase. This calls for adjustment of the
w 25 mg BOD5 / l and can reach values down to 5 mg/l
asure accurately and reproducible. Depending on the
  BOD5 / t respectively (at 25 mg/l and 10m3 flow).




 and control of emissions and the water flow per tonne of
mg COD / l.




 ations are normally achievable.




sed in non-integrated paper mills is normally either ECF
between 30 and 50%. However, this reduction is partly
 on the purchased pulp and chemical additives used
Table 6.32                   Emissions levels associated with the use of BAT for different fuels

Released substances          Coal                    Heavy fuel oil          Gas Oil                 Gas
                             100-200 1               100-200 1
mg S/MJ fuel input           (50-100) 5              (50-100) 5              25-50                   <5
                             80-110 2                80-110 2
mg Nox/MJ fuel input         (50-80 SNCR) 3          (50-80 SNCR) 3          45-60 2                 30-60 2
mg dust/Nm3                  10-30 4 at 6% O2        10-40 4 at 3% O2        10-30 at 3% O2          <5 at 3% O2
Notes:
1) Sulphur emissions of oil or coal fired boilers depend on the availability of low-S oil and coal. Certain reduction of
sulphur could be achieved with injection of calcium carbonate.
2) Only combustion technology is applied
3) Secondary measures as SNCR are also applied; only larger installations
4) Achieved values when electrostatic precipitators are used
5) When a scrubber is used; only applied to larger installations

Emission levels associated with BAT from auxiliary boilers incinerating own bio fuels and/or different fuels are given in Table 6.32. It has to be noted that auxiliary
boilers within the pulp and paper industry are of a very variable size (from 10 to above 200 MW). For the smaller only the use of low-S fuel and combustion
techniques can be applied at reasonable costs while for the larger also control measures. This difference is reflected in the table. The higher range is considered
BAT for smaller installations and is achieved when only quality of fuel and internal measures are applied; the lower levels (in brackets) are associated with
additional control measures like SNCR and scrubbers and are regarded as BAT for larger installations.
different fuels

                                        Bio fuel (e.g. bark)

                                                  <15

                             60-100 2                   (40-70 SNCR) 3
                             10-30 4 at 6% O2




different fuels are given in Table 6.32. It has to be noted that auxiliary
 W). For the smaller only the use of low-S fuel and combustion
 s difference is reflected in the table. The higher range is considered
 are applied; the lower levels (in brackets) are associated with
 tallations.
                                                 Indication for energy consumption associated with
                                                 the use of BAT for different types of paper
Table 6.33                                       production per tonne of product

                                                 Process heat consumption         Power consumption
Type of mill                                     (net) in GJ/t                    (net) in MWh/t
Non-integrated uncoated fine paper               7,0-7,5                          0,6-0,7
Non-integrated coated fine paper                 7,0-8                            0,7-0,9
Non-integrated tissue mill                       5,5-7,5 1                        0,6-1,1
Notes:
1) In tissue mills the energy consumption depends mainly on drying system used. Through air drying
and creping consumer significant process heat up to 25 GJ/t (according to ETF)
          BAT Checklist for Non Integrated Paper Mills
          BREF document
          December 2001
          The checklist is a resume of BREF-document for Non Integrated Paper Mills. There is therefore a need to check BREF-document for a more detailed explanation.



          BAT reference no.
          (BREF-document,
          Section 6.4.2.)                 BAT definition                                                    BAT reference no.    BAT status              BAT Action Plan

           Non Integrated Paper Mills

          General Measures

                                      1 Training, education and motivation of staff and operators
                                      2 Process control optimisation
                                        Ensure sufficient maintenance of technical units of paper
                                      3 mills and associated abatement techniques
                                      4 Environmental management system

          Measures for Reducing Emissions To Water
                                    Minimising water usage by increased recycling of process
                                  1 waters and water management                                             6.3.1

                                        Control of potential disadvantages of closing up the water
                                        system. Microbial control, proper design and material
                                        selection helps to keep the surfaces in clean condition.
                                        Recycle stream monitoring by measurements and lab
                                        analysis determine the performance and the quality of the
                                        shower water etc. Automation, online measurements and
                                        accurate process control area essential for effective and
                                      2 stable papermaking                                                  6.3.2 / 6.3.8

                                          Construction of a balanced white water, filtrate and broke
                                          storage system and use of constructions, design and
                                      3   machinery with reduced water consumption when practicable         6.3.3
                                          Measures to reduce frequency and effects of accidental
                                          discharge including training of staff and precautionary
                                      4   techniques                                                        6.3.7
                                          Collection and reuse of clean cooling and sealing waters by
                                      5   use of heat exchangers or a cooling tower
                                          Separate pre-treatment of coating wastewaters by
                                      6   membrane technique or by flocculation                             6.3.6
                                          Substitution of potentially harmful substances by using non
                                          toxic and better biodegradable product aids and process
                                      7   chemicals                                                         6.3.12
                                          Effluent treatment of wastewater by installation of
                                          equalisation basin and primary treatment ( not considered as
                                      8   BAT as a stand alone technique)                                   6.3.9
                                          Secondary or biological treatment of wastewater and or in
                                          some cases secondary chemical precipitation or flocculation
                                      9   of wastewater                                                     6.3.10 / 6.3.11

          Measures for Reducing Emissions To Air
                                  1 Installation of low Nox technology in auxiliary boilers   6.3.15
                                  2 Using low sulphur oil and coal in steam boilers
                                  3 Use of combined heat and power generation                 6.3.16
                                    Using renewable sources like wood or wood waste to reduce
                                  4 emissions of fossil CO2

          Measures for Reducing solid waste

                                        Minimisation of the generation of solid waste and recover, re-
                                      1 use and recycle reusable materials as far as possible
                                        Separate collection of waste fractions at source and, if
                                        necessary, intermediate storage of residuals/waste, to allow
                                        for a greater proportion to be reused or recycled rather than
                                      2 land filled
                                      3 Reduction of fibre and filler losses                            6.3.4
                                        Pre-treatment of sludge (dewatering) before further utilisation
                                      4 or final disposal                                               6.3.13
                                      5 Recovery and recycling of coating wastewaters                   6.3.5

                                        Reduction of the amount of waste to be land filled.
                                        Identification of possibilities for recovery operations and - if
                                        feasible - utilisation of waste for material recycling or
                                      6 incineration of rejects and sludge with energy recovery.

          Energy saving measures
                                        Implementation of a system for monitoring energy usage and
                                        performance. Energy management includes setting,
                                        controlling, reviewing and revising energy performance
                                      1 targets

                                        More effective dewatering of the paper web in the press
                                        section of the paper machine by using wide nip shoe
                                      2 pressing technologies (this does not apply to tissue mills)         6.3.17

                                        Use of energy efficient technologies as e.g.. High
                                        consistency slushing, best practise refining, twin wire
                                        forming, optimised vacuum systems, speed adjustable
                                        drivers for fans, high efficiency electric motors, well sizing of
                                        electric motors, steam condensate recovery, increasing size
                                      3 press solids or exhaust air heat recovery systems                   6.3.18
                                        Reduction of direct use of steam by careful process
                                      4 integration by using pinch analysis

          Noise attenuation

                                          Reduction of noise levels audible in the vicinity of paper mills 6.3.19

          Chemical usage




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                                      Ensure the availability of a database for all used chemicals
                                      and additives containing information on the chemical
                                      composition of the substances, degradability, their toxicity for
                                  1   men and environment and potential of bio-accumulation
                                      Application of the principle of substitution i.e. less hazardous
                                  2   products are used when available
                                      Measures to avoid accidental discharges to soil and water
                                  3   from handling and storage of chemicals
                                      Design and operation of facilities in such a way that
                                  4   dangerous substances cannot escape




D:\Docstoc\Working\pdf\63c8fdaf-34dc-4d47-abb1-8fb57dce0380.xls                                          10/12/2011   8/8

				
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