Biological Reclamation of Waste Dump by Utilization of Fly- Ash for by xft76262

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									    Biological Reclamation of Waste Dump by Utilization of
        Fly- Ash for Plant Growth and Soil Conditioner
                                                    Dr.R.B.Panda1 and P.M.Dash2

                                                                ABSTRACT

  Many researches have been carried out on the study of different aspects of Fly Ash and its utilization. Huge
  amount of fly ash is being generated from coal based thermal power plants in our country. Few of it is being
  utilized in different ways. Although fly ash contains a small amount of toxic elements and heavy metals but
  due to having some macro- and micro- nutrients in it and its physical characteristics it can be used as soil
  amendments and soil conditioner. Toxic effect of fly ash is found to be negligible and concentration of toxic
  elements is found to be within permissible limit on utilization in Plantation work. 20 % addition of fly ash (by
  weight) can be applied with good earth for plantation work in waste or degraded land.

  Electricity Power, it may be come from thermal, hydral or atomic, becoming a integral part of our day to day
  life without which our modern society can not dream a single minute. Out of total global power demand, coal
  based thermal power is meeting about 2/3rd of the total requirement. In our India about 80 % of the total
  energy demand is meeting by coal alone. In India low grade, high ash content coal are being used for power
  generation resulting generation of huge quantity of fly ash and bottom ash, which amount is at present 60
  million ton and which is estimated to exceed 100 million ton in coming 2010AD. Thus generation of huge
  quantity of fly ash posses a multiple environmental and other serious problems beside occupying large areas
  of land for its storage and disposal. Environmental problems are :

  a. Being very fine gets air borne very fast. Ignition causes serious health hazards like silicosis, fibrosis of
  lungs, bronchitis, pneumonitis etc over wide areas and also affects flora and fauna and aquatic life.
  b. Danger of contamination of ground and surface water by traces of toxic and heavy metals presents in fly
  ash.
  c. Affects aquatic life cycle of nearby water bodies.
  d. Contaminates the good cultivating topsoil of nearby agriculture field through wind propagation.
  e. Reduce the photosynthesis rate hence reduce the field crop production of the nearby agriculture field by
  deposition of fly ash over the leaves of agriculture crops through wind.
  f. Requires huge area for disposal thereby decreases area availability for other purposes such as cultivation
  etc. therefore in order to minimize the harmful effects of fly ash it is always to important to find out ways and
  means not only for safe disposal but also for meaningful large scale utilization of fly ash.
  g. Even though serious efforts are now being made and number of new technology developed for the
  utilization of fly ash for different purposes, hardly 6 to 7 % of fly ash generated is being utilized in India which
  is far below in percentage of utilization in foreign countries.


As such disposal of huge quantity of fly ash requires large                   nutrients viz. Ca, Mg, Cu, Zn, Fe etc in sufficient quantities
quantity of either useful or wasteland. Thus in Indian scenario               a part alkaline in nature with pozolanic properties helps in
the need for bulk utilization of fly ash in eco-friendly manner               water          and          nutrient       transportation.
requiring immediate and urgent measure to be taken in                         -Fly ash for waste / degraded land management /
this direction. In different parts of world many researches                   reclamation - Fly ash is a good soil aerator contains
have been done on utilization of fly ash by many                              essential elements for plant nutrient as well as fly ash helps
researchers. Few of them are follows:                                         in increasing of porosity and permeability of soil thereby
                                                                              increases water retention time and water holding capacity
-Manufacture of bricks and other building materials-Fly ash                   can be used as soil conditioner for the degraded / waste
owing to its excellent pozolanic properties used as cement                    land.
material        of      different       building     works.                   -Fly ash as mine fills:
- Fly ash utilization in agriculture including reclamation of                 Sand obtained from river flowing in coal field mines has
waste and degraded land- Fly ash contains majority of plant                   been used for filing of the under ground voids. However due
                                                                              to over exploration of sand from riverbeds for stowing
1. Managing Director & Env. Consultant, , 71, V.I.P Colony, Nayapalli,
Bhubaneswar- 15, Tel 553 314 Email: rasb ¡Vpanda@hotmail.com,                 purposes and its slow rate of replenishment due to different
2. Scientist (Environment), M/s Nature care                                   causes, its availability is becoming scarce by day by day

ENTMS 2002 Geominetech Conference Proceedings                            68                                            ENTMS 2002
thereby necessitating the using of alternative material for              some macronutrients and its physical characteristics it acts
stowing. Now it is being proved. Fly ash is a good and                   as a soil conditioner for tree growth.
potential element as an alternative to sand for under ground
mines filling.                                                           Fly ash is usually alkaline and so it can be applied in soils
                                                                         in order to check pH and its physical characteristics. It is
Even though a good deal of works have been carried out by                also a source of plant nutrients except having humus and
different scientists of different part of world on utilization of        nitrogen.
fly ash by different means still a lot of works has to be
done. In this content the author has carried out some                    To balance the carbon content we have applied cow dung
experiments on utilization of fly ash for biological                     manure and Vermi ¡V Compost at least 2 Kg per plant. We
reclamation of waste dump in mining area utilizing fly ash               also used bio-fertilizers like azatobacter, ribosome, and
a soil conditioner, plant growth accelerator.                            phosphobactrin in selective manner. After plantation
                                                                         watering is carried out in regular intervals along with other
UTILIZATION OF FLY ASH AS SOIL CONDITIONER:                              post plantation work as usual. The results of plant growth
                                                                         have been observed as follows:
Fly ash a byproduct of thermal power plants is rich in macro-
and micro- nutrients and suitable physical properties.                   The results of plant growth have been observed as follows:

It can be used as soil amendments on waste over burden                   - Tree species such a Gamhari, Sisoo, Chakunda,
dump and eroded waste land. Fly ash when added to hard                   Krishnachuda, Radhachuda, Babul and Siris were grown
soil in the proportion of 1:5 to 1:10 by weight it improves              up well. The survivability was found to be more than 85% in
the physical properties of soil. Acid soil became neutral. It            off-season taking varieties of plant species including fruit
improves the soil porosity, permeability soil and hence also             bearing plants.
moisture retention capacity of soil increases. Hence if
afforestation will be made then plant growth will be good                - Growth by height and stem diameter ¡V Height of all tree
over that area due to easy penetration of the roots and                  species increased rapidly with the application of fly ash.
moisture in the soil.                                                    Species like Gamhari, Chakunda and Siris, grown well with
                                                                         respect to height (1.5 ft to 3 ft during six months). Increase
                                                                         in stem diameter was distinctly visible in species like
UTILIZATION OF FLY ASH FOR BIOLOGICAL                                    Chakunda, Krushnachuda and Sirisa.
RECLAMATION OF WASTE DUMP:
                                                                         - Leaf growth ¡V Number of leaves formed during six months
It has been observed that fly ash is very useful in plantation           have been counted. It is more in species like Gamhari,
work for plant growth as well as soil conditioner due to                 Sisoo, Chakunda, Krushnachuda, Radhachuda,
presence of some macro- and micro- nutrients and its                     Phesphesia and Kamalagundi. Some flowering plants also
physical characteristics.                                                grown well.

We are in the job of biological reclamation of mines waste               - Water holding capacity ¡V The presence of fly ash with
dump through indigenous species since last 14 years.                     topsoil increased the water holding capacity or the water
Recently we have applied fly ash on waste dump areas of                  retention time. Initially it was difficult to retain water more
Talcher and Ib Valley and carried out massive plantation of              than one day on pure waste dump material or with soil
indigenous species where there is no sign of topsoil. We                 only. With the addition of fly ash with topsoil, the water
applied mixture of good earth and fly ash in different ratio in          retention times increased to 3 ¡V 4 days. This helps in
different plots during plantation work. The chemical                     easy transportation of nutrients to the plants.
composition of fly ash of these areas thermal plants is as
follows:                                                                 With a little increase in local temperature, the field becomes
                                                                         dry quickly. Hence caring of plants will be very difficult
SiO2 %   Al2O3%    Fe2O3%     CaO %    MgO %     SO3%    Alkalies        generally during summer season and the survivability of
59.84     21.01      11.55      2.30     0.84     1.35     0.96          the plant species. This has been now avoided by the
                                                                         application of fly ash, which keeps the soil moisturized for
In general Coal of Mahanadi Coal Fields are highly siliceous             a long time.
and acidic in nature containing about 30 % silica and 45 ¡V
60 % Clay. Density of fly ash of Orissa thermal power                    For the study of plant growth we have planted different
stations is 600 ¡V 900 Kg/m3, Specific gravity is 2.3 ¡V 2.5             species in different ratio of soil and fly ash as soil + 0% fly
and particle size varies from 53 micron to 75 micron. So                 ash, soil + 5% fly ash, soil + 10% fly ash, soil + 20% fly
the major constituent is silica. But due to the presence of              ash and soil + 50% fly ash. The observations noticed are
                                                                         given in the tables 1 to 6.
ENTMS 2002 Geominetech Conference Proceedings                       69                                            ENTMS 2002
                                                                    Table-6
Table-1                                                             Concentration of trace metals in leaves of Sisoo plants after
Height after 6 months                                               6 months (unit mg/Kg)
   Tree species Height in CM      Soil (100%)   Soil (80%) +        Fly ash
fly ash (20%) Soil (50%)
+
                                                                    Added            Zn           Cu            Fe           Mn
  fly ash (50%)                                                     0%           3.5           2.3             9.6           6.2
  Karanja                  46.2          72.4          52.7         50%          4.2           2.2             9.8           9.3
  Chakunda                 30.5          46.5          34.1         10%          4.6          3.1           11.2           10.4
  Gamhari                  46.7          65.9          49.4
                                                                    20%          4.8          4.3           16.4           11.6
  Sisoo                    70.6          81.1          73.4
                                                                    50%          5.6          5.1           17.8           14.6
Table- 2
                                                                    The following adverse effects may be occurred by utilization
Collar diameter of tree species after 6 months of plantation
                                                                    of fly ash:
Sl. No. Tree species Collar Diameter in CM
      Soil (100%) Soil (80%)                                        a. Ground water contamination
+                                                                   b. Fly ash contains a small portion of heavy metals, which
fly ash (20%) Soil (50%)                                            may percolate down and pollute ground water. The solubility
+                                                                   of these elements is less than 10 % (Rohriman,1997)
fly ash (50%)                                                       c. At Central Fuel Research institute, Dhanbad, it was
1.            Karanja        1.2         1.8            0.9         observed that the quality of ground water did not change
2.            Chakunda       1.8         2.2            1.9         with the application of fly ash. All the parameters including
3.            Gamhari        2.9         3.2            2.8         the trace elements and toxic metals contents were within
4.            Sisoo          1.8         2.4            2.1
                                                                    the permissible limits.
                                                                    d. Uptake of heavy metals and toxic elements by the
                                                                    vegetation ¡V RRL, Bhopal conducted a study regarding
Table - 3
                                                                    the uptake of trace and toxic elements by vegetation crops
Concentration of trace metals in leaves of Karanja plants
                                                                    and it was observed that the uptake is quite low and
after 6 months (unit mg/Kg)
                                                                    remaining within the normal range.
Fly ash
                                                                    e. Radio active contamination:
Added           Zn           Cu          Fe           Mn
                                                                    V.Vijayan and S.N.Behara, Institute of Physics,
0%            5.6            8.2        5.9          8.7
                                                                    Bhubaneswar, 1999 have conducted an experiment on
5%            6.2            9.4       9.6            8.9
                                                                    analysis of heavy metals using gamma nuclides on crop
10%          5.8            9.6         9.1         12.2
                                                                    grown fly ash treated soil at Farakka (p-231). The analytical
20%          6.9            10.1        10.7        12.8
                                                                    results showed that the concentration of heavy elements
50%         13.4            12.3        12.8        13.1
                                                                    and radionuclides in crops and soil produced are within the
                                                                    permissible limit.
Table-4
Concentration of trace metals in leaves of Chakunda plants
                                                                    CONCLUSION
after 6 months (unit mg/Kg)
Fly ash
                                                                    With the addition of 20% fly ash by weight the successful
Added            Zn           Cu            Fe         Mn
                                                                    growth of plant species such Karanja, Sisoo, Gamhari and
0%           3.4           2.1            5.8          5.6
                                                                    Chakunda have been observed. It is also seen that Gamhari
5%           2.7           3.8            7.2          7.6
                                                                    species shows good results as compared to others by collar
10%           4.2          3.9             9.6         9.4
                                                                    diameter with a mixture of soil and fly ash (80% soil + 20%
20%           5.1          4.2           9.8         11.2
                                                                    fly ash). It also observed that fly ash is very helpful in
50%          8.4           5.6          14.5         15.8
                                                                    maintaining water holding capacity and moisture content
                                                                    in the soil. When the addition of fly ash is increased, the
Table -5
                                                                    concentration of trace elements in the plant species also
Concentration of trace metals in leaves of Gamhari plants
                                                                    increased. But at 20 % use of fly ash (i.e. 80 % Soil + 20
after 6 months (unit mg/Kg)
                                                                    % Fly ash) the concentration of trace elements transported
Fly ash
                                                                    to plants was found to be medium and the height & collar
Added           Zn          Cu            Fe          Mn
                                                                    diameter of the plant species like Karanja, Gamhari, Sisoo
0%           4.3          6.5            9.2          5.1
                                                                    and Chakunda were found to be comparably good. Hence
5%           5.3          7.8           14.2          6.7
                                                                    utilization of Fly Ash for plantation is highly beneficial.
10%          7.8         10.9           15.6          7.8
20%          9.2         10.2           16.7          7.2
50%          10.4         12.5           23.1         8.1

ENTMS 2002 Geominetech Conference Proceedings                  70                                           ENTMS 2002
         Air Pollution Control & Enviornmental Management
                                                     A. Deb* Harijeevan Alva**

                                                 ABSTRACT
 Environmental Management and Pollution Control pose a major concern to all sectors of Mining, Steel,
 Power, Cement and other core Industries. The wide range of industries coming under the purview of Pollution
 Control demonstrates the need of EFFICIENT POLLUTION CONTROL TECHNIQUES, to meet the stringent
 norms as stipulated by Central Pollution Control Board under the Ministry of Environment and Forest and
 implemented by the State Pollution Control Boards.With the advancement of science and increase in awareness
 of the problems related to pollution, a challenge has arisen to solve/control the spread of Air Pollution in
 Industrial Establishments. In addition to these, recent world developments have targeted towards cleaner
 process technology to reduce pollution.


ENVIRONMENTAL REGULATION
                                                                             In the following paragraphs we are highlighting the techno-
                                                                             economic optimal solutions for dust control in contrasting
The strict environmental regulation and legislation as well
                                                                             material handling applications for different industries by Wet
as the sensitivity of the Pollution with respect to air pollution
                                                                             Dust Suppression and with introduction of Conveyor Care
has motivated KAVERI to adopt new approaches in
                                                                             Products.
Engineering, Design, basic research and education. Modern
concept is to have waste reduction which itself is preliminary
                                                                             PORT TRUST – VISAKHAPATNAM
measure to waste treatment and its disposal. Waste
                                                                             WET DUST SUPPRESSION SYSTEM FOR CARGO
reduction and pollution control integrated with production,
                                                                             HANDLING AREAS.
needs a fundamental engineering research base which has
been developed by KAVERI for controlling the air borne
                                                                             This mega project, one of the first of its kind in the country
dust emitted due to Transport, Transfer, Storage and
                                                                             is under commissioning stage; value of the project being
distribution of bulk materials.
                                                                             approx. Rs.6 Crores. Individual Dust Suppression System
                                                                             is being provided for the following areas:
HEALTH & SAFETY ASPECTS.
                                                                             Sl.No Area              Approximate Area      Approximate
The time has come when people resent to put up with dusty                                            of Stock Yard         Storage
environment. Production and Maintenance Managers are                                                                       Capacity
fully aware of pollution caused by, during handling of bulk                  01    General Cargo    68,000 Sq.Mtrs.        1,10,000 MT
materials and its after effects. Plant personnel do not want                       Berth
                                                                             02    West Quay Berths 1,80,000 Sq.Mtrs.      2,60,000 MT
to expose themselves to dusty environment. Present day
                                                                             03    North / South of 1,15,000 Sq.Mtrs.      2,00,000 MT
technologies have solutions to eliminate the dust nuisance                         S4 Conveyor
and create a healthy and safe working atmosphere. In this
paper, we are focusing on tackling of Air Pollution Control                  General Cargo Berth is located in Vizag Outer Harbour
in Ports and Storage Areas, Open Cast Mines and Bulk                         adjacent to the Iron Ore Berth. The berth mainly handles
Material Handling Plants.                                                    general cargo and coal. The coal stockpiles adjacent to
                                                                             the berths are stacked upto a height of about 4.5m in
INTRODUCTION                                                                 available areas. The coal gets unloaded onto the berth with
                                                                             the help of cranes mounted on the ships. From the berth
Awareness of pollution caused by, during handling bulk                       the coal is loaded on dumpers with the help of front-end
materials is the reason why industries are giving major                      loaders.
attention to control this situation. The problem associated
with the operation and maintenance of Plant for handling,                    West Quay Berth are located on the western side of the
storage, distribution of materials in bulk are profuse. The                  Northern Arm, due south of the Iron Ore Handling Complex.
variety of materials being handled in bulk varies from fine                  The berth mainly handles coal. Coal is stacked upto a height
dust to rocks. We shall restrict ourselves to the control of                 of about 4.5m in available areas. There is no definite pattern
Micronics fugitive dust. Like in any engineering situations,                 of stacking. The area is divided among various handling
many methods and methodologies are available to solve                        contractors and stacking is done haphazardly. The coal
the pollution problems.                                                      gets unloaded onto bunkers located on the berths with the
* General Manager (Proj. Mktg. Dev.), Kaveri Ultra Polymers Limited.         help of cranes mounted on the ships.
Bangalore
** Deputy Manager Marketing. Kaveri Ultra Polymers Limited. Bangalore

ENTMS 2002 Geominetech Conference Proceedings                           71                                              ENTMS 2002
North / South of S4 Conveyor these areas are located                   PROCESS PLANT - INDIAN ALUMINIUM CO. LTD.,
on the north and south of S4 conveyor, bounded by GFCL                 BELGAUM
area on the west and R2/R4 areas on the east. Coal is
stacked in some places. Although present stacking is not               DUST SUPPRESSION SYSTEM FOR RED MUD POND
much, coal is proposed to be stacked upto a height of
about 4.5m in available areas. There is no definite pattern            The waste product generated from producing Alumina is
of stacking. The present stacking is done haphazardly. The             Red Mud which is a very fine light particle. This waste Red
coal is transported from the berths with the help of dumpers           Mud is transported from the INDAL factory premises to an
and dumped in the stockpile.                                           adjacent dumping yard of approximately 250,000 Sqm. The
                                                                       Red Mud dumping by tippers is a continuous process. Pres-
Simultaneous Loading & Unloading.                                      ently the maximum height of the dumped material is approx.
For each of the above areas, the dumpers carry the coal                20 Mtrs. from the peripheral road level, situated on the out-
and dump them in the stockpile. From the stockpiles, the               skirts of the Belgaum Town Center and is just on the edge
coal is retrieved with the help of front-end loaders and loaded        of the National Highways No. 4 between Belgaum to
on to railway wagons or dumpers as per requirements.                   Pune.
Loading and unloading operations proceed simultaneously.
                                                                       Serious Pollution Problem.
Scheme
                                                                       During the dry season, on certain occasions the fine Red
The basic scheme is to suppress the fine ionic dust particles          Mud Particles have caused disruption to traffic movement
by controlled spray of water at the required pressure,                 for several hours on the National Highway apart from pollut-
augmented by RCC tanks and individual Booster Pumps,                   ing the near by residential areas. To avoid this Air Pollution
Control Valve, Duplex Filters etc. The pumps shall be                  phenomenon, INDAL tried several measures, which includes
operated from the respective pump houses and operation                 water spraying through perforated pipes with water being
of pumps and valves will be manual.                                    supplied by a Booster Pump through piping network. How-
                                                                       ever such measures did not achieve the minimum expected
Water is sprayed with the help of circular swiveling type              results.
sprinklers. These sprinklers with an approximate throw
radius of 40 metres are mounted on vertical stand posts,               Tailor made Dust Suppression System.
which is tapped from underground water headers. The above
sprinklers are located along the periphery and roads. For              To eliminate this dust nuisance, Kaveri designed a plain
sprinklers located inside the stockpiles, the stand-posts              water dust suppression sprinkling system tailor made to
rises upto a height of 5m to avoid submergence by the                  the actual site conditions like:
stacked material. The flow of water through the Sprinklers
is controlled manually with the help of globe valves. The              ·   Dumped Red Mud being fine powder like material does
sprinklers are bunched in groups – each bunch of sprinklers                not have a consolidated base.
is controlled by butterfly valves.                                         On applying the water there are possibilities of per-
                                                                           sons getting stuck in the stockyard.
Sprinkler Operation                                                        To take care of this unsafe situation the scheme had
                                                                           been designed to facilitate the operator to operate the
Each group of sprinklers is operated in cycles. The number                 system from the boundary of stacked Red Mud.
of cycles operated in one shift is determined at site based            ·   Water inside the natural pond is slightly alkaline and
on prevailing weather conditions and fugitive dust generation.             to accommodate the same the Sprinkler body were
The operator will decide this by observing the extent of                   designed and manufactured with cast iron material and
wetting after one cycle. The sprinkling duration may be                    the internal parts with Stainless Steel.
slightly increased / decreased by the operator based on
the extent of wetting and after one cycle is completed the             System configuration
next area is covered and so on til all areas are covered.
Judging the extent of wetting and fugitive dust generation,            The system comprises of Booster Pumps, Duplex Filter,
start of second cycle is decided and active areas of stockpile         Control Valve, Modular Piping Network for easy shifting,
may require more sprinkling than inactive areas.                       Sprinklers Support and full circle Sprinklers with an ap-
                                                                       proximate throw of 30 Mtrs. radius.
                                                                       The total area is divided into different segments of Sprin-
                                                                       kler Headers with Sprinklers positioned to ensure that 100%
                                                                       wetting of the area is achieved. Each sprinkler header con-
                                                                       stitute several sprinklers – quantity depending upon the
                                                                       length of the header.
ENTMS 2002 Geominetech Conference Proceedings                     72                                            ENTMS 2002
Sprinklers on each header operates simultaneously. The                designed sprinklers fixed on sprinkler headers. The high
frequency of the operation of the Sprinkler Header depends            pressure is achieved with help of suitably designed Booster
upon the climatic condition and the dryness of the Red                Pump. Depending upon the length of the Haul Road, the
Mud at individual areas.                                              system can be segregated into several segments which
The system is in operation since January 2001, and has                can be controlled either manually or electrically; operated
been proved to be extremely useful and successful.                    through composite electrical control panel installed within
                                                                      the pump house shed. The sprinklers are selected based
OPEN CAST MINES                                                       on the width of the road and average ambient temperature.
HAUL ROAD – WET DUST SUPPRESSION SYSTEM                               The sprinklers will be operated depending on the frequency
Dust problem                                                          of the movement of HEMM, density of generated dust as
                                                                      well as climatic condition of the area for that particular period
On haul roads, generation and accumulation of dust is                 of time.
common phenomenon due to movement of Heavy Earth
Moving Machinery (HEMM). The generation of dust                       Compound MDS added Dust Suppression System.
assumes dangerous proportions causing health hazard for
those working at site as well as bringing down the efficiency         COMPOUND MDS is applied to increase the efficiency of
of the workmen. Most of the Haul roads in open cast mines             the spraying system, which is essential to improve physical
are not of permanent nature and under goes various                    phenomenon between solution and dust particles and to
changes conforming to the profile of the mines operation.             reduce surface tension of water. By reducing the surface
The haul roads are unsealed and therefore the road surface            tension of water, COMPOUND MDS creates micro fine mist
gets cracked and crushed due to the heavy pressure of the             and greater spray dispersion for more area coverage.
HEMM which operates at high frequency.
                                                                      By controlled dozing of Compound MDS with plain water,
Present system of Dust Suppression applied on                         fine air borne particles of ore /minerals which are hydro-
Haul Roads.                                                           phobic converts to hydrophilic.

Presently water tankers of 10000 to 35000 litres capacity             Compound MDS controls water evaporation and during re-
are used with gravity feed to wet the haul road during the            peat spray of water, it helps immediately to absorb the
mining operation. Inspite of continuous water sprinkling at           water thereby gradually reducing the water tanker trips.
a substantial cost of water, diesel, equipment and man
hours; the movement of dumpers causes generation of dust              Functioning of Compound MDS.
particles which pollute the entire area including foliage of
vegetation on either side of haul road.                               Kaveri has developed the latest technology of Dust
                                                                      Suppression System by providing special chemical additive
Disadvantages of present system.                                      or wetting agent – COMPOUND MDS, which is mixed at a
                                                                      ratio of 1:4000 (one part of chemical to four thousand parts
·    Erratic sprinkling contributes water to either flow or           of water) in a specially designed proportioning unit.
collects rather than effectively helping in dust suppression.
·    Frequency of watering of roads is at undetermined                When diluted in such minute quantities, COMPOUND MDS
intervals, with the result, the dust suppression efficiency is        has tremendous wetting, penetrating and sprinkling powers.
very poor.
·    Use of Graders become essential resulting in higher              The Compound MDS increases the effectiveness of water
maintenance costs.                                                    by:
·    Consumption of excessive quantity of fuel adds upto              ·   Accelerating the absorption of fines.
uneconomical running costs.                                           ·   Fines generated remain in the agglomerating mass of
·    Wear and tear of HEMM parts adds to maintenance                  the material mostly adhering to the surface.
costs, resulting in higher operating costs.

Methodology of Dust Suppression for Haul Roads.                       ·  Accelerating the water dispersion, assisting in the
                                                                      homogeneous conditioning of fines.
The total system will be modular type so that maximum
flexibility is achieved for transferring the system from one
place to another depending on the profile of the mines and            Techno Commercial Advantages for using the Dust
location of haul road. The solution is spread in the form of          Suppression System.
mist generated at a high pressure through specially
                                                                      1. Overall productivity of the mines increases.


ENTMS 2002 Geominetech Conference Proceedings                    73                                              ENTMS 2002
2. By suppressing the air borne dust better health condi-                 Kaveri dust suppression system is designed to prevent
   tion of the worker will prevail.                                       micron sized dust particles from getting air borne by
3. The HEMM are better maintained due to lesser wear                      suppressing it at its source. To achieve this, the system
   tear thereby increasing the equipment life and avail-                  configuration consists of a chemical dozing pump, booster
   ability.                                                               pump, proportioning unit, control panel with relevant
4. Break down and maintenance costs are reduced.                          instrumentation and accessories.
5. Replacement of air filter of dumper reduces consider-                  The unique feature of the system are the tailor made spray
   ably thereby saving cost of replacement.                               jet mist nozzles operating with minimum moisture addition.
6. A cleaner environment will help to promote congenial                   The system is designed to operate automatically with the
   worker and management relationship.                                    help of material sensors and Solenoid Valves located at
   Reference Installations of Kaveri Dust Suppression                     strategic locations within the material handling system. The
   System                                                                 system is designed in such a way, that Spray through
                                                                          Nozzles will only operate when the material flows through
SAIL     Bhilai                    Raw Material Stock Pile.               the Belt Conveyors. The material sensors senses the
INDAL    Durgamanwadi Bauxite Mine Haul Road. After                       material and actuates the Solenoid Valve to spray on the
                                   installation had become the
                                   First Bauxite Mine in the world        material and stops automatically in the absence of the
                                   to receive ISO 14001.                  material even if the conveyor continues to run. The number
MCL      Lakhanpur & Chingriguda                                          of Nozzles on a Nozzle Header would depend upon the
         Colliery                  Haul Road / Railway Siding –           belt width material flow, belt speed, material characteristics
                                   Coal Mine.
SECL     Gevra & Kusmunda Colliery Railway Siding – Coal Mine.            and other relevant parameters.
INDAL    Lohardaga Bauxite Mine    Haul Road.
JVSL     Bellary                   Raw Material Stock Pile.               SPILLAGE AND CARRY BACK

                                                                          Cost Analysis
BULK MATERIAL HANDLING SYSTEMS — CONTROL
OF AIR POLLUTION                                                          Spillage and Carry back has always been a constant source
                                                                          for generation of fine dust particles which in turn pollutes
INTRODUCTION                                                              the surrounding environment. Cost analysis indicates that
Air Pollution at transfer points during handling of bulk ma-              while designing a conveyor system, if little more effort is
terial had always been a perennial problem and the indus-                 made towards selection of efficient cleaning system, it not
try was not aware of a scientific solution to the problem.                only reduces cleaning cost but also reduces wear of belt
The transportation in Bulk Material Handling & Mineral Pro-               top cover enhancing its life and thereby effecting reduction
cessing Industries is mainly through belt conveyors during                of overall cost of conveying bulk materials. Keeping com-
which management of dust generation, spillage and carry                   prehensive records, it has been found that reduction in run-
back have always been a challenge to the Plant Produc-                    ning cost far offsets the investment cost towards preven-
tion and Maintenance personnel. The vulnerable areas for                  tion of carry back and better cleaning and spillage control
generation of dust particles on a belt conveyor handling                  system.
bulk material is at the discharge and at the material load-
ing points. In the following paragraphs, we would be con-                 Belt Cleaning – Conventional Type
centrating on the latest technologies available with Kaveri               In the past and even still now, manufacturing industries
to foster an environment that encourages professional ex-                 frequently employed improvised devices like Rubber or
cellence.                                                                 Plastic to clean belts. However this provided only a cheap
After a continuous process of development through a full                  answer but not an effective solution.
fledged R & D team which works in our in - house R&D
center and also make visits to the plants and installation of             Kaveri Multiblade Sprung Blade Scrapers – Updated
various clients to study their problems, collect samples                  Technology
data etc. and, if required, call for the services of experts to           Kaveri introduced the Multiblade Sprung Back Elastomount
solve their problem, Kaveri has the distinction to be the                 Scrapers for an effective solution for belt cleaning.
sole proven manufacturers and suppliers of the following
combination of Techno-Commercial viable system / prod-                    All KAVERI Sprung Blade Scrapers operate on the prin-
ucts required to control air pollution in totality.                       ciple of blade being inclined against the direction of the
                                                                          belt travel, exerting minimal force on the surface to be
COMPOUND MDS ADDED DUST SUPPRESSION SYS-                                  cleaned. Each individual blade has a sprung action so that
TEM                                                                       the blades maintain constant contact with the belt even if
                                                                          some wear out more quickly than others.
Dust Generation during handling and distribution of materials
are enormous and contrasting with different scenarios.

ENTMS 2002 Geominetech Conference Proceedings                        74                                            ENTMS 2002
This angle ensures that the sprung blade scrapers are easily         IMPACT PADS
able to remove the final layer of material adhering to the           Introduction
belt.                                                                The Impact Zone in a Conveyor System is an area that
                                                                     needs critical attention.
Primary & Secondary Belt Scrapers
Where a Sprung Blade Scraper is to be operated under                 It is an established fact that excessive impact on belt
severe conditions, it is always advisable to employ a Pri-           surfaces due to material lump size and height of fall Conveyor
mary Belt Scraper to ensure optimum effectiveness and                Belt sags, gets damaged, spillage occurs, pollutes the
economy. This is particularly pertinent where high percent-          environment, maintenance increases contributing to cost
age of coarse / sticky materials are moved which have a              escalation vis-à-vis; reduced machine availability.
tendency to cake onto the belt thus reducing the load on
the Secondary Scraper which follows the primary scraper.             Impact Zone – Impact Idlers (Conventional Type)
This combination of Primary Belt Scraper in conjunction              KAVERI with proven experience on bulk solid handling have
with the Secondary Scraper helps in giving maximum clean-            successfully designed and manufactured Impact Pads to
ing efficiency.                                                      substitute functional disadvantage of conventional Impact
                                                                     Rollers installed at specific intervals within the Impact Zone.
Scraping Tips                                                        The gap between the Impact Rollers leads to sagging of
Scraping tips are of High grade tool steel, Polyurethane or          belt which in turn contributes to spillage / polluting the
Tungsten Carbide and the selection of these tips is based            environment.
on various operating parameters and our experience in this
matter plays a very vital role.                                      Impact Pad – Updated Technology
                                                                     The unique features of Kaveri Impact Pads is that the design
SPILL STOP SKIRT BOARD SEALING SYSTEM                                eliminates the gap which occurs in the belt between two
Skirt Board - Conventional Type.                                     idlers and thus the skirting material works as a positive
Bulk material spillage had always been a constant source             seal not allowing material to spill out.
of concern.                                                          Impact pads are suitable for all bulk conveyor systems with
Conventional rubber strips were being used but in today’s            varying impact conditions and raw materials having different
situation of constantly rising productivity norms, this              lump sizes.
conventional system has become ineffective.                          Impact Pads are installed in the longitudinal direction (i.e.
                                                                     in the direction of the belt) consisting of UHMW Polymer
Skirt Board Sealing System – Updated Technology.                     backed by rubber easily fitted to a steel frame of modular
Kaveri introduced a cost effective superior designed sealing         design with suitable fasteners below the conveyor belt tailor
system with segmented over lapped blocks to eliminate.               made to suit any troughing angle.
·   Material - spillage, blockage and piling                         The Impact Pads have no moving parts and therefore regular
·   Plant downtime and to ensure                                     maintenance is not required.
    - Optimum Productivity
    - Increased Recovery of Material                                 Recommended Use
    - Reduction of Labour Costs.                                     The combination of Impact Pads and Spill Stop Skirt Board
                                                                     Sealing System effectively sandwiches the conveyor belt
One of the most important areas where spillage occurs is             thereby eliminating any possible spillage of fine material.
at the loading points. This is mainly due to improper loading        This ensures that the surrounding environment is pollution
on the conveyor, improper width, height, and length of skirt         free and thus safe for the plant personnel
board and sealing system. KAVERI skirt blocks are
moulded from specialised wear resistant rubber / polymer.            REFERENCES
The skirt blocks are designed to be adjusted in small                Our above products are in use and performing very well at
increments to conform to the belt contour, thereby providing         Cement, Power, Chemical, Mining & other Bulk Material
an effective seal against any material spillage. The blocks          Handling Plants throughout the country and the number of
have an overlapped design thus ensuring that spillage is             satisfied clients & the Performance Certificates we have
controlled effectively.                                              received are a testimony to our credentials.




ENTMS 2002 Geominetech Conference Proceedings                   75                                            ENTMS 2002
              Urgent Need for Control of Vehicle Emissions
                           in Mining Industry
                                                        Dr.S.K.Puri *
India is among the top ten mineral producers in the world             has been introduced in a few mines. In pit crushing and
and stands third in coal production after China and U.S.A.            conveying has been introduced in Piperwar in C.C.L. At
The present production of coal of the order of about 320              Gevra, the biggest coal producing mine in India, inpit crushing
MTY is supporting about 70,000 MW of thermal power                    and conveying of coal is already in vogue.The economics
generation and with the development plan to produce                   of belt conveying are particularly attractive in large volume
200,000 MW by 2010,the share of thermal power generation              operations; in mines where steep climbs are involved and
would be about 150,000 MW.Thus, in the next ten years, it             whose haul distances are more than a few kilo metres.The
will be required to double the production of power grade              rigid configuaration of belt conveyors at times make their
coal i.e.,by the year 2010,the country will be required to            introduction cumbersome.A second problem is that for
produce 550 MTY of coal of about 35% ash only for thermal             conveyor transportation the mined mineral has to be within
power generation.If the past 30 years of post nationalisation         certain size parameters. For quality reasons too the mineral
period is to act as a guide line, such rapid increase in coal         has to be of consistent size suitable for customers.In hard
production would be feasible only from opencast mines.The             rock mines that means crushing prior to conveying and
coal production which had stgnated at 88.41 MT in 1974-               tends to limit conveyor haulage to coal fractions only.
75 reached a level of 329 Mt in 2001-2002.The phenomenal              Advances in mobile equipment designs using rubber tyres
growth in coal production in the past in our country has              and crawlers have introduced aflexibility in crushing and
been made possible by laying greater emphasis on opencast             conveying hereto unavailable.
mining.Open Cast mines have proved to economic and safe,
contributing to larger coal recovery and have greater                 DUST HAZARD DUE TO OPEN CAST MINING
potential for large sized production units to effect economies
of scales with lesser gestation period in order to meet the           il     Higher size of equipment and transfer of minerals at
accelerated growth in power coal demand. The share of                 transfer points is likely to generate dust in larger quantities
open cast mines in CIL projected to go up fro 26% in 1974-            because of the scales of operations.Wide spread concern
75 to about 81% in 2001-2002.The share is likely to shoot             is being expressed in all quarters about the likely
up to 85% by the terminal year (2011-12) of XI th 5 year              deterioration in envirnmental quality especially the increase
plan. For economic reasons we will have to adopt latest               in concentration of suspended particulate matter (SPM)
technology for open cast mining.                                      within and around the mining site.

GLOBAL OPEN CAST TRENDS                                               l      Vehicular traffic on the haul roads of mechanised
                                                                      mines have been identified as the most prolificn source of
l     Upgradation in equipment size                                   fugitve dust and can contribute as much as 80% of dust
Almost all the major dumper manufacturers have launched               emitted from a surface coal mine ( Axetell 1978 )
high capacity models in 120-170T range. Recently a few
companies have introduced 240-300 Tonnes dumper                       Another study conducted by Tan (1984) and Chadwik et al
commercially.                                                         (1987) on surface coal mine established that about 50% of
                                                                      total coal dust was produced during journey of dumper on
l     Higher capacity shovels are becoming available to               unpaved haul road while 25% for both loading and unloading
work with these large capacity dumpers. Rope shovels of               of dumpers.
46 cubic metre bucket size and hydraulic shovels of 50
cubic metre bucket size are in regular production.Wheel               CHARACTERISATION OF MINE DUST
loaders of 28 cubic metre size with 1800 H.P. engine with a
loading rate of 2800 tph are being used with 240T dumpers.            The physical characteristics of air borne mine dust most
                                                                      often associated with the incidence of health hazard are
Shovel - Dumper combination has become a standard                     the size distributions and mass concentration of dust.
practice in mines where the gradients are more than 1 in 5.           Precaution against dust as per CMR - 1957 :-

l     Conveyor Transport                                              The Coal Mines Regulations,1957 has been ammended in
As an alternative to wheeled transport for coal and                   1990 to strengthen the provision relating to precautions
overburden,crushing and conveying of coal and overburden              against dust. It requires that owner,agent,or manager of
                                                                      every mine shall take such steps as are necessary for the
* Chief General Manager,Katras Area,Bharat Coking Coal
Limited,Dhanbad

ENTMS 2002 Geominetech Conference Proceedings                    76                                            ENTMS 2002
minimising of emissions of dust which enters at any work                to polycyclic armatic hydrocarbons (PAHs).Typical of this
place below ground or on surface and for ensuring that                  class of compound is benzo (a) prene - B(a)P - a notorious
exposure of workers to respirable dust ( less than 10 u                 cancer inducing agent or carcinogen
size ) is limited to an extent that is reasonably practicable,
but in any case not exceeding the limits that are harmful to            CH+1/2O2      —————>         B(a)P +   H2 O
the health of persons.For the purpose of this regulation a              Oil + Oxygen —————> Brenzo(O)prene+ Water
place is not deemed fit for the work if the 8 hrs. time weighted
average concentration of airborne respirable dust exceeds               The above reaction has been considered with oxygen but
3 mg/cum provided free respirable silica present in the dust            in actual air is used for combustion which contains Nitrogen
is less than 5% and the value arrived at by dividing the                of about 77% by weight or 79% by volume.The presence of
figure of 15 with the percentage of free respirable silica              Nitrogen in air during combustion produces oxides of
present in other cases.                                                 Nitrogen under higher temperature and pressure.

EMISSION OF RESPIRABLE PARTICULATE MATTER                               POLLUTANTS PRODUCED DUE TO FUEL COMBUSTION
DUE TO USE OF DIESEL IN OPEN CAST MINING                                IN DIESEL ENGINES

A large number of open cast,Heavy Earth Moving Machinery                Quantitative Specifically   Subjective
(HEMM), operates on diesel. For xample, Dumpers,
Dozers,Graders,Water Tankers,Generators,Welding sets,                   Unburnt Hydrocarbons        Smoke and odour
some small capacity Excavators etc., use High Speed                     Carbonmonoxide              Other pollutants come from
Diesel as fuels in their prime movers.Roughly in Indian open            Oxide of Nitrogen           Evaporative emissions
cast mines 0.8 litre per tonne of coal production is used.              Particulates                Crank case emissions
                                                                        Sulphur Compounds
Open cast production during 2001-2002 was of the order of               Other Compounds
263 million tonnes. It can be safely estimated that 210.56
million litres of High Speed Diesel was used for Open Cast              ADVERSE EFFECTS OF POLLUTANTS ON HEALTH
Over Burden Removal and Coal Production.
                                                                        Pollutant                   Health effects
Pollutants produced due to combustion of fuels
                                                                        HC                          Some kind of HCs are
The combustion equation for fuel such as oil with oxygen                                            cacinogenous. Hydro Carbons
can be written as                                                                                   contribute to Ozone formation
                                                                                                    and they are also indirect green
CH + 2O2 —————> CO2        +      2H2 O                                                             house gases.
Oil + Oxygen —————> Carbon dioxide + Water                              Oxidants                    Difficultbreathing,chest
                                                                        (Peroxyacetylnitrate)       tightness, respiratory coughing
This looks fairly harmless for the urban environment as
carbon dioxide (although a green house gas) is not really               Ozone                       Soreness ,coughing
poisonous.
                                                                        TSP                         Increased susceptability to
However if there is not enoigh oxygen during combustion,the                                         other pollutants,fine particles
equation may look like                                                                              less than 10 micron especially
                                                                                                    particles less than 2.5 micron
CH + O2      —————>        CO +      H2 O                                                           enters the lungs and
Oil + Oxygen —————>Carbon monoxide + Water                                                          associated with cardiovscular
                                                                                                    disorder and asthma.
The carbon monoxide is a poisonous gas as it combines                   SO2 &SO4                    Increase asthma attacks.
with red blood corpuscles and can kill by asphyxiation at               NO2                         Soreness,coughing particularly
higher concentrations, or                                                                           among people with respiratory
with even less oxygen we may get carbon or simple smoke                                             illness.Nox contributes to the
                                                                                                    formation of acid rains and can
CH+1/2O2      —————>       B(a)C +  H2 O                                                            damage vegetation
Oil + Oxygen—————> Carbon/Smoke + Water                                 CO                          Visual acuity affects central
                                                                                                    nervous system as it reduces
At lower temperatures, where there is relatively little oxygen,                                     the oxygen carrying capacity
reactions may cause rearrangement of atoms that can lead                                            of blood.


ENTMS 2002 Geominetech Conference Proceedings                      77                                            ENTMS 2002
Exhaust emissions are tested on following test cycles                          vehicles in mines depends upon
                                                                               >>     Routine Maintenance
1      13 mode test cycle for Auto application,Idle,Peak                       >>     Fuels and Lubricants Quality
Torque, Rated 10%,25%,50%,75%, and 100%.Loads and                              >>     Operating Condition
net value calculated on weightage at different points.
                                                                               Influencing Parameters on Diesel Emission
2     Generator sets are tested on 5 mode test cycles as
per ISO : 8174 - 4                                                             Quality of air
                                                                               Engine Compression
3    Constructions are tested on ISO : 8178 - 4C                      8        Fuel Injection System
mode test                                                                      Oil Consumption
                                                                               Oil Quality
Present Norms                                                                  Fuel Quality

i)     Automative 60 - 150 BHP - Euro - I                                      Factors for High Smoke

ii)  Construction 160 - 800 BHP Central Motor Vehicles                         Inadequate air supply to cylinders
Regulation is working on this and presently under draft                        Improper Combustion
mode                                                                           Restrictions in exhaust Gas Flow
                                                                               Other factors (Fuel and altitude)
iii)   Generator Drive ISO 8178 - 5 details & limits                           Case to be exercised
       Nox      7 to 9.3 gm/bhp/hr                                             (During Free Acceleration Test)
       HC       0.2 to 0.9 gm/bhp/hr                                           Equipment Maintenance and Calibration
       CO       0.3 to -3 gm/bhp/hr                                            Selection of correct probe diameter and placement of probe
                                                                               Keep correct pressure and temperature
Emission Norms                                                                 Warmed up engine
                                                                               Consistent pressing of accelerator
Pollutant         Euro-I          Euro - II   Euro - III    CNG                Reading consistency
Nox               8               7           5             1.38
HC                1.1             1.1         0.6           0.02               Influencing Factors
CO                4.5             4           3.5           2.5
PM                0.36            0.15        0.07          0.07               (For Free Acceleration Test)
                                                                               Fuel quality
Note:                                                                          Atmospheric Pressure,Temperature and Humidity
Still emissions norms are not finalised for construction                       Equipment Calibration
application.Due to the various test cycles it will be possible                 Free Acceleration Method
to establish the factors only with sophisticated equipment.                    Vehicle Condition
However emission regulations for Europe - 2000 and USA -
EPA - 2000 for construction machines are reproduced                            Eqiupments needed for Emission Test
below:-
                                                                               i)     Hartridge Smoke Meter
Europe Appication Test     NO x         HC     CO    PM   Smoke                ii)    All Smoke Meter
2000              Cycle    gm/kw        gm/kw- gm/kw gm/kw                     iii)   Other equivalent Full Flow Opaci Meters
                           -hr          -hr    -hr   -hr
Europe            8 mode
2000 Constn.      ISO-8178- 9.2         1.3    5      0.5   -------            Advantages of Free Acceleration Test
                  C1
US-EPA            8 mode                                                       Simplicity of the test
2000 Constn.      ISO-8178- 9.2         1.3    5      0.54 ------              Low cost
                  C1
                                                                               Of full throttle smoke
VEHICLE EMISSION CONTROL TECHNOLOGY                                            Emission Measurements

                                                                               Smoke Opacity under free acceleration
The situation of air pollution is considered critical for large                Smoke Opacity under fuel throttle performance
open cast mines in India. The emission level of in-use



ENTMS 2002 Geominetech Conference Proceedings                             78                                          ENTMS 2002
Gaseous emissions like CO,HC,NO x under 13 mode test                   0.87% for heavy duty vehicles.
Particulate matter under 13 mode test                                  *In India sulphur content has been 0.50% in 1996 and it
                                                                       has been further reduced to 0.25% by September 1999.
STRATEGIES TO REDUCE AIR POLLUTION DUE TO
VEHICULAR MOVEMENTS IN MINE                                            *It is necessary to have low sulphur diesel for meeting norms
                                                                       beyond Euro - II norms (for Euro I and II norms, sulphur
-Regular monitoring of air pollutants should be done to                content in diesel is 0.3%). The refineries will need to take
establish a data base for studying trends in pollutants levels.        steps for bringing down sulphur content.
                                                                       *Low sulphur of 0.5% is available from 1st January 2001.
-Studies on quantification of air pollution emissions at the
mine should be taken up to classify equipmentwise air                  CONCLUSIONS
pollution sources.
                                                                       The Indian emission norms may be further tightened in the
Air pollution in the mining area can be checked to a large             year 2005 to graduallu catch up with the standards prevailing
extent by adopting various provisons for prevention and                in advanced countries. The Indian diesel engine
control of air pollution as described below.                           manufacturers need to incorporate new tchnologies such
                                                                       as turbo charging with after cooling,combustion
-All service roads should be bitumen coated black topped               optimisation, electronic fuel management and use of after
metal road.                                                            treatment technologies and devices such as catalytic
                                                                       converters, and particulate traps to conform to the present
-Belt conveyor transport system should be adopted wherever             as well as future emission norms.
feasible.
                                                                       Automobile industry,manufacturers of HEMM and oil
i-Green belt should be provided around mining area,along               industry in India must work closely to find solutions for
roads and also in the residentials area.                               lower emissions.Emission norms for construction
iv)    Use of clean fuel - Sulphur content in Diesel Oil               machineries used in open cast mines need to be set at
                                                                       the earliest therafter regular monitoring to ensure conformity
*aSulpher in diesel has direct effect on Sulphur dioxide(SO2)          with the norms.Wherever the norms are not being met,
and particulate (PM) emissions and indirectly on other                 preventive and mitigative measures need to be taken.
pollutants due to its poisoning effect on catalytic converter.
                                                                       ACKNOWLEDGEMENT
*Preliminary data released fro auto/oil industry shows that
lowering of the sulphur level in the disel oil from 2000 ppm           The author is grateful to BCCL management for useful
to 500 ppm, reduced overall emissions of particulate from              discussion,suggestions and providing facilities for
light duty diesel engine by 2.4% and for heavy duty diesel             study.The author is grateful for granting permission for
engine by 13%.                                                         presenting the paper.
*The relationship between particulates emission and sulphur
level in diesel oil was found to be linear,for every 1000 ppm          REFERENCES
reduction in sulphur in diesel oil, there is a reduction of
particulate emission by 0.16% for light duty vehicles and              1       C.P.C.B. Publication
                                                                       2       M.O.S.T. Guidelines for Vehicular emission




ENTMS 2002 Geominetech Conference Proceedings                     79                                            ENTMS 2002
 Coir Geotextiles and New Generation of Soil Conservation
                in Mining & Allied Industries
                                              KERALA COIR CORP. LTD
INTRODUCTION                                                 5.     Drainage                                   16
It has become difficult to imagine geo-technical construc-            6.       Asphalt Overlay                 17
tions without the incorporation of geo materials in modern
                                                                      7.       Separation / stabilization      42
construction practices. While geo-synthetics dominate all
sphere of application, the natural organic fibre (coir) have          3. Coir Geo-Textiles: characteristics
now proven the mettle to match with geo-synthetic in ar-
                                                                      The potentials of natural fibre geo materials lies in areas of
eas involving erosion, filtration, drainage and separation.
                                                                      short to medium term applications, with high performance
Geo-synthetic in the simplest sense of the term, are per-
                                                                      and a life span of 2 to 3 years. Coir fibre is coarse, rigid and
meable textile fabrics used to prevent the soil from migrat-
                                                                      strong and degrades slowly. The slow rate of degradation
ing, while maintaining the water flow.
                                                                      is attributed to the high content in the fibre (35 to 40 %).
Coir & Jute (nets and mesh fabrics) was probably first                Some of the important properties and characteristics are
used in erosion control application in the early 30’s, where          highlighted below:
soil conservation were said to have taken a modified form
                                                                      ·       The high tensile strength of coir fibre protects steep
of coir/jute mesh used to wrap cotton bales. These mate-
                                                                      surfaces from heavy flows and derbs movement.
rials were laid on the slope to prevent wash – off from newly
seeded grounds.                                                       ·        Five (5*) to Ten (10*) years longevity, allows for full
                                                                      plant and soil establishment, natural invasion and land
The geo-textiles role was to protect and promote vegetar-
                                                                      stabilization (* under different soil, temperature, rainfall and
ian cover during its formative period after which it degrades
                                                                      climatic conditions).
over a period of time and mixes with the soil providing for
valuable nutrients etc., Geotextiles(woven/nonwoven/blan-             ·        Totally biodegradable, 100% natural coir fibre func
ket/composite/cells/3-d structures/modules) forms permit                       tions as a soil amen dent.
free flow of water both normal and interlayer directions.             ·       Water absorbent fibers act as a mulch on the sur-
Recent trend in both the developed and developing coun-               face and as a wick in the soil mantle.
tries very clearly suggest that the role of geo-textiles exist
in fluid control and solid control applications.                      ·       Provides an excellent micro climate for plant es-
                                                                      tablishment, natural invasion and balance healthy growth.
GROWTH OF GEO-TEXTILES /GEO-MATERIALS
                                                                      ·        Re-vegetarian measures encourage the restoration
Geo-textiles have seen unrivalled growth with a forecast              of terrestrial and aquatic riparian habitat.
by the United Nations International Trade Centre (UNCTD)
of 1,400 million sq. meters produced by the new millennium.           ·        Environmentally friendly, biodegradable and aes-
Europe & North America markets each account for 40%                   thetically pleasing.
with the remaining 20% attributed mainly to Japan, Asia &             ·        Easy to install and follows the counter of the soil
Australia. Natural fibre geo-textiles (Coir, jute sisal, hemp,        surface.
straw and other similar fibers) account for less than 1%.
Even this 1% runs in to millions of square meters, which              (* Life expectancy of the natural fibers depends on the soil
should be exploited to the fullest extent for usage and ap-           structure & composition, climatic conditions,UV, radiation
plications. With the present thrust on environmental friendly         aspects, rainfall at site, temperature and type of application).
aspects and non-polluting engineering materials and the               .Geotextiles, itsfeaturesand benefits derived
ban on synthetic plastics, HDPE, LDPE HMHDPE, so
that coir geo-materials have immense potentials.                      Highlights the features & benefits derived with its applica-
                                                                      tion for solving environmental problems.
Table ,Application vs percentage (%) of different major
application.                                                          Technology of recp’s / stitch bonded Erosion

Sl. No. Application areas            Percentage                       control blankets:

1.       Reinforcement                    4                           The production of stitch bonded blankets involves three basic
                                                                      steps:
2.       Slit Fences                      6
                                                                      (a) Coir fibre decurling, opening, dosing & metering, uniform
3.       Erosion Control                  7                           web preparation. With the required coir fibre web density.
4.       Linings                          8                           (b) Introduction of top & bottom nettings, with the desired

ENTMS 2002 Geominetech Conference Proceedings                    80                                             ENTMS 2002
mesh size, weight and the required tensile strength aspects             The onset of the monsoon. Similarly experiments were also
of the blanket in the machine and cross direction as per                carried out at M/s Ann Arian Mines, Chitradurga, Karnataka,
ASTM 4595 standards (wide width tensile strength value in               for controlling erosion due to severe winds.
KN/meter at a traverse speed of 10mm per minute and
                                                                        TECHNOLOGY OF EROSION CONTROL
specimen size of 20cm X 5cm) and the life expectancy of
the blanket.                                                            Introduction concept of vegetation programmed in erosion
                                                                        control.
c)Stitching of the blanket in the machine direction at intervals
of 50mm across width of the blanket and rolling them into               The basic ingredients for successful erosion control and
rolls of desired diameters.                                             vegetation program could be summarized as follows:
APPLICATION OF ECB’S IN THE MINING INDUSTRY                             · Soil analysis & modification as required.
The mining industry in India is an age old profession and               · Properly prepared seedbed.
second only to agriculture as the world’s oldest and valuable
                                                                        · Correct seed or solon selection using appropriate
industry, exploitation of minerals are going on since pre
                                                                        quantities.
Christian era. Currently the country produces 4 furl. 11
metallic, 49 non-metallic and 20 minor minerals. Over the               · Fibre mulch applied at proper rates to ensure germination
years the mines waste dumps have accumulated in leaps                   and quick growth.
and bounds causing damage to land, soil, water, flora, fauna            · Proper fertilization selection and rates to enhance seedling
as the mining land has to be broken open. The soil                      vigor.
composition of the dumps, being very soft and delicate are
prone the soil loss and severe erosion problems, resulting              · Addition of soil amendments and stabilizers as insurance
in severe pollution to the environment.                                 against failure.
The mine wastes are composed of 60% later tic soil and                  · Irrigation plan or natural moisture potential based on
40% soft clay (magniferrous/phyllitic). Mining waste is sterile         reason.
with no organic matter and biological activity. The waste               · Follow up maintenance plan.
dump and garden soil analysis are show in table 2, which
indicates that the soil is deficient in basic nutrients like            Soil fertility analysis: The soil you are protecting must be
nitrogen, phosphorous and potassium. The environmental                  fertile if it is going to support the establishment of vegetation.
parameters and chemical analysis of water is shown in                   To determine whether the soil structure has the ability to
table.                                                                  naturally enhance growth. The soil to be analyzed with
                                                                        an exclusive
A typical extraction development performance in tones in
the mining industry is as follows.                                      extraction method to identify the mineral and organic
                                                                        balance naturally healthy soil. Natural healthy soil means
(Good mining performance should have a stripping ratio of               naturally healthy vegetation. The ability of the soil to natural
1:2.5)                                                                  hold water and nutrients for delivery to the plant and saplings,
The traditional bio engineering techniques, like plating of             seeds will reduce the cost of chemical fertilizers and help
acacia plants, cashew plants at regular spacing intervals               to determine an economical erosion control blanket design
(to establish vegetative covers), spreading a cover of laterilte        and selection
soil over the mine dumps slopes have been inadequate to                  INDEX TESTS REQUIRED FOR EROSION CONTROL
provide relief from the severe erosion problem’s. The present
                                                                           blankets and selection
problems faced are available of laterilte soil, high transpor-
                                                                        · Thickness
tation cost for movement of laterite soils to the dump areas
                                                                        · Resiliency
etc.,With the present government rules and regulations to
                                                                        · Mass per unit area
protect the environment from pollution, it is imperative that
                                                                        · Mesh size
we look for alternate solutions for the problems faced.
                                                                        · Water absorption
Application of new generation coir erosion control blankets             · Swell
with special design features could be an effective alternate            · Stiffness
to provide for solutions and speed up the vegetation process.           · Light penetration
7.Experimental trials at M/s Sesa Goa Limited, Goa (Sonshi              · Smoldering resistance (against fire hazards)
& Codli Mines)(Year 2000 and 2001)                                      · Tensile properties
                                                                        · Slope recommendation
During the year 2000 & 2001, two experimental Sites in                  DESIGN, SELECTION AND FABRICATION OF ECB’S
their Sonshi and Codli Mines were selected for application              FOR MINE DUMPS
of coir geotextiles (rolled erosion control blankets). The
blankets were installed before                                          The erosion control blanket designed and developed for the

ENTMS 2002 Geominetech Conference Proceedings                      81                                              ENTMS 2002
purpose had a strength of 3.5 kN per meter both in th            in the needle looms. Weight: 35 gsm.
machine and cross direction (as per ASTM 4595 at a
                                                                 · Stitching of HDPE blanket with high strength
traverse speed of 10mm per minute. The ingredients of the
                                                                 polypropylene thread (multi filament without twist – 1000
blanket it as follows:
                                                                 denier).
· Coir fibre content (untwisted or de curled): 400 gsm
                                                                 INSTALLATION TECHNIQUES AND GUIDELINES
·Selection of top netting: made from HDPE monofilament
                                                                 Stand recommendations of International Erosion Control
yarn with 10mm mesh size fabricated/woven in the needle
                                                                 Association (IECA) and Erosion Control Technology Council
looms. Weight: 35gsm.
                                                                 (ECTC), guidelines adopted for this purpose by our Head
· Selection of Bottom netting: made from HDPE                    Office & systematic laying procedures .
monofilament yarn with 10mm mesh size fabricated/woven




ENTMS 2002 Geominetech Conference Proceedings               82                                          ENTMS 2002
    With Best Compliments From


    The Kerala State Coir Corporation Ltd

                                                     Fax: 91674-509237


ENTMS 2002 Geominetech Conference Proceedings   83                       ENTMS 2002

								
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