|Environmental Technologies Industries
|India Environmental Export Market Plan|
Environment Problems and Requirements
|Chemicals||Product-specific pollutants, with particular problems related to hazardous materials. In many small-scale firms, pollution treatment systems remain non-existent. Pollution prevention expertise is also required.|
|Metal finishing including electroplating||Almost 50,000 units in India. The most serious pollution problems consist of rinsing operations discharged into municipal drains. Almost all small operations discharge wastewater without treatment. Effluent contains heavy metals such as zinc, nickel, and chromium and toxic salts such as cyanide. Air emissions are also a problem. In-process pollution prevention services are the greatest single requirement, as the high cost of endof-pipe treatment systems is prohibitive. In larger firms, where treatment facilities now exist or can be installed economically, there is a need for sludge management technologies.|
|Food and food processing||Oil, suspended solids, and biochemical oxygen demand in effluents. Need for expertise in pollution prevention, as well as cost-effective wastewater treatment technologies, including anaerobic systems.|
|Brick kilns||Air pollution from chimney exhaust containing particulates, sulfur dioxide, and carbon monoxide. Land degradation is also a problem. There is a need for simple, inexpensive treatment technologies.|
|Drugs||16,000 plants, of which 96 percent are small-scale. Discharge of partially treated liquid wastes containing toxics is a major concern. Organic solid wastes are disposed in unsecured landfills without adequate characterization, pre-treatment, or control.|
|Pesticides||20 percent of the 90,000-tons-per-year-production capacity in this sector is small-scale. Release of toxic substances in air and water and on land. Inadequate process control instrumentation. Limited technical and financial capabilities to handle toxic wastes and sludge. Such plants require incineration, de-watering, ozonation, measuring, and control technologies.|
|Hazardous waste disposal||Industry still trying to understand the requirements of the new Amendment Rules, January 2000. Almost all the standards for storage of hazardous waste and discharge limits for treated leachates have been revised. Measuring, control, and dosing technologies are the weakest technology links. There is a need for know-how in all areas pertaining to hazardous waste management, including the design and installation of adequate disposal facilities and treatment plants. Most incineration technologies currently in use are not comparable to international standards. There is also a need for know-how related to maintenance and control of plants as well as environmentally compatible management of landfill sites.|
|Integrated iron and steel plants/mini steel plants/small foundries||One of the most important sectors in India. There are seven large plants, 170 mini plants, and more than 5,000 small foundries. Raw material is highly variable in quantity and in combination with obsolete cupola-based production technology, results in serious air and water problems, as well as slag and ash management problems. Need for a wide range of expertise technologies and products such as, semi-automatic molding technologies for small foundries, sand regeneration technologies, coated electrodes for electric arc furnaces, efficient sand coolers, improved sand mixers, metal filters, spectrometers, and full mould casting processes.|
|Thermal power plants||Almost 70 percent of total generation met by coal-based thermal power plants. Air pollution, mainly comprising fly ash, sulfur oxides and nitrogen oxide emissions from the stack, and coal dust from the coal handling conveying and crushing system is the biggest problem. Ash content of power plant coal can vary between 20 percent and 60 percent in a single day, and is around 38 percent on average. Electrostatic precipitators installed currently are out dated. Ash removal is carried out by the wet method and fly ash suspension is dumped without any remediation measures. Fly ash sludge contributes a lot to water pollution. Because of existing shortfall in power supply, older inefficient stations cannot be closed down, but the existing ash precipitation and connected ash handling system definitely needs to be completely replaced with new improvised designed systems and higher efficiency electrostatic preciptators.|
There is also a need for expertise and technology in fly ash utilization, coal beneficiation, upgrading and retrofitting of existing plants, fluidized bed firing, nitrogen oxide removal, flue gas desulfurization, fabric filters, and continuous waste gas measuring devices.
|Sugar||More than 400 sugar mills where the main concern is high biochemical oxygen demand levels in the effluent streams and also high oil and grease content. Need for enhancing expertise in pollution prevention and wastewater treatment technologies particularly anaerobic treatment technologies.|
|Fermentation industries||In breweries, the suspended solids content in wastewater is relatively high and also leads to the odor problem. In distilleries the main problem is that of excessively high biochemical oxygen demand in effluents (spent wash) contributing also to odor nuisance. Need to evolve treatment technologies, particularly anaerobic and biological treatment methods.|
|Textiles||Mainly water pollution from heavy metals, total dissolved solids, color, and organics. High concentration of dissolved solids. There are serious gaps in control technologies and available treatment technologies are quite expensive.|
|Dye and dye intermediate||Over 64 major units and around 700 units are in the small-scale sector. Main pollutants are heavy metals, acids, organics, and phenolic compounds leading also to high biochemical oxygen demand and chemical oxygen demand levels. High total dissolved solids, chloride and sulfide salt concentrations. Need for evolving expertise in wastewater minimization and other in-plant measures for pollution prevention. Available treatment technologies are quite expensive and there is a need to evolve low-cost treatment methods.|
|Large pulp and paper||There are more than 96 major large-scale units and around 500 small-scale units. The annual production is 3.8 metric tons (MT). The average organic chlorine released is 2-10 kg/ton. Air pollution basically comprises organo-chlorine, mainly in the form of sulfur emissions and the release of suspended particulate matter. The other solid wastes include (per ton of production) the following;|
Most mills discharge wastewater on land or in surface water bodies resulting in higher soil salinity levels. Chlorine bleaching leads to water pollution, apart from high biochemical oxygen demand/chemical oxygen demand/total dissolved solids/dissolved solids and lignin levels. Large-scale units also contribute to air pollution by emitting particulate matter, gaseous pollutants, and mists.
|Small pulp and paper||A small pulp and paper unit discharges high biochemical oxygen demand and high chemical oxygen demand, including high concentrations of lignin, chlorine, and suspended solids. Poses environmental problems through water source contamination. Fiber and chemical recovery is not carried out in such units because of prohibitive cost. Wastewater treatment technologies are quite expensive. Need to evolve cost-effective waste minimization and waste treatment technologies.|
|Tanneries||Around 2,500 tanneries in the country. Major problems are through wastewater, which contains heavy metals, toxic chemicals, chlorides, lime with high dissolved and suspended salts, and other pollutants. Most of the tanneries are located in clusters. Hence they prefer to have common effluent treatment plants. Rapid modernization of the industry with the shift toward chromium tanning dyeing using synthetics has made the water pollution problem very significant. Color removal from effluents is a major problem.|
|Man-made fiber||Around 74 units in India, including 56 units of synthetic fiber, 15 units of semi-synthetic fiber, and three units of glass fiber.|
|Synthetic fiber plants||Environment problems could be posed by high chemical oxygen demand or high levels of dissolved and suspended solids in wastewater, including caprolactam, dimethylterephathalate (DMT), ethylene glycol, and acrylonitrile and polypropylene used as raw materials in synthetic fiber units.|
|Semi-synthetic fiber plants||Wastewater from semi-synthetic fiber plants includes high chemical oxygen demand, high suspended solids, and, most important, zinc, and poses environmental problems. Wastewater treatment technologies include raw materials recovery and chemical recovery/reuse technologies. Need to evolve cost-effective chemical recovery technologies and waste minimization technologies. Need to evolve low-cost treatment technologies, which could be affordable to small units.|
|Paint industry||Around 1,400 units, spread all over the country. The wastewater from paint industry contains high chemical oxygen demand and biochemical oxygen demand, oil and grease, heavy metals and phenolics, and poses environmental problems. The cost of wastewater treatment is quite high. Need for evolving wastewater minimization technologies and costeffective wastewater treatment technologies. Air pollution from these units needs to be controlled through low-cost technologies.|
|Caustic soda industry||There are 25 major units and a few units in the unorganized sector. Outdated mercury cell technology used in the caustic soda manufacturing process poses severe environmental problems as the wastewater contains mercury salts (chlorine, calcium, and sulfates), acids, and high concentrations of suspended solids. The treatment cost is quite high, as mercury recover/reuse technologies are not easily available at low cost. Need to evolve costeffective mercury recovery/reuse and treatment technologies.|
|Inorganic chemicals||Around 60 units spread all over India producing chemical compounds of chromium, manganese, nickel, copper, zinc, cadmium, mercury, lead, etc. These units pose severe environmental problems as the wastewater streams contain all the above-said heavy metals, cyanides, sulfates, high concentrations of dissolved as well as suspended solids, and high chemical oxygen demand levels.|
The treatment technologies are very expensive, as the wastewater composition is complex in nature. There is a need to evolve cost-effective waste minimization, metal recovery, and treatment technologies.
|Bakeries||Under the broad classification of bakeries this sector involves basically two types of units - breads and biscuits - from which the solid waste generated is 5 kg/ton and 5.7 kg/ton, respectively. The present methods of disposal, such as incineration, animal feed, and municipal garbage, are not effective. Specific wastewater generated 0.11 and 0.05 cum./ton for the continuous and non-continuous operations in the bread units. The biochemical oxygen demand and chemical oxygen demand loads are also very high in the noncontinuous process, which is mainly due to the cleaning activities at the end of the production period, leading to frequent discharges of concentrated wastewater. The wastewater generation is in the range of 0.02 to 0.11 cum./ ton.|
|Soft drinks industries||The annual production is estimated to be at the rate of 2,520 million bottles (0.5 million tons). This sector is classified into two sub-sectors:|
1. Synthetic-based units,
2. Fruit-based units.
The only sources of air pollution are the combustion of fuels used in utilities such as package boilers and diesel generator sets. The solid waste generated in the synthetic sector is high (1.7 kg/ton of product in large units). The total solid waste generated consists of used filters, spent activated carbon, broken bottles, and tetra packs, which are currently being disposed of as municipal garbage or on land outside the factory premises. The wastewater flow rates in the synthetic-based units and fruit-based units are 94 cum./day and 90 cum./day, respectively. The biochemical oxygen demand load is 76 kg and 51 kg, respectively. The higher specific pollution load in the large units is due to the additional loads from the bottle washing machines and discharge of beverages from rejects. Wastewater from washing activities requires neutralization; the remaining stream requires oil and grease traps as pre-treatment. Thus, effective in-plant segregation and stream specific pre-treatment are preferred prior to biological treatment.
|Confectioneries||The total production per year in the large-scale industries and small-scale industries is 50,000 and 150,000 tons respectively. The solid waste generated is 1.4 and 2.25 cum./ton for large-scale industries and small-scale industries respectively. There is immense potential for reducing wastewater volume and pollution loads (implementation will also result in the reduction of the capital investment and annual operation and maintenance expenses for the effluent treatment system). The following technically feasible pollution abatement measures have been assessed:|
|Rice mills||The principal fuel used in this industrial sector is rice husk, which has an ash content of 20 percent. The chief sources of air pollution are the emissions from the stack of the furnace used for boilers. Steam-generating systems used in most units are not effective. Fugitive emissions are another point of concern in the rice mills. The dust blown up by the natural air current in the work environment remains suspended for varying periods, resulting in respiratory disorders. Landfilling of boiler ash and paddy handling rejects is the prevalent method of solid waste disposal. Noise pollution is a serious problem in the working zones. Wastewater generation ranges between 8 to 22 cum./day with high biochemical oxygen demand levels.|
|Fruit/vegetable processing units||The average solid waste generated is 0.2 ton/ton of product produced. Fruit units (especially the pineapple, mango, apple, and guava processing units) produce 1,300 kg of waste per ton of product. Vegetable units (especially tomato, green pea, cabbage, and potato processing units) produce 760 kg of waste per ton of product. Pollution load is mainly due to the concentrated discharges arising from balancing operations. The wastewater generated is 91.45 cum./day. Biochemical oxygen demand levels vary significantly and are dependent on the raw material being processed (for example, in apple processing units biochemical oxygen demand is as low as 2.6 kg/day; for the other fruits and vegetables it can be as high as 42 to 86 kg day).|
|Viscose rayon staple fiber industries||Coal being the principal fuel leads to high emissions of particulate matter and sulfur dioxide. Wastewater generated is high in temperature, has high pH value, suspended solids, biochemical oxygen demand, chemical oxygen demand, zinc, and total dissolved solids. Colored effluent is another point of concern for these industries. Other significant air pollutants are carbon and hydrogen sulfides, fly ash, and sodium sulfate. The solid waste generated includes fly ash, sulfur, sludge, slag, waste charcoal, and biological waste. Available treatment technologies are not adequate to meet the required standards in these industries.|
|Cement||During the dry season, when the ambient temperature is very high, coal and raw material is dry and the dew point of the kiln gases reduces, thereby affecting the performance of electrostatic precipitators. The greatest roadblock in the efficient running of the electrostatic precipitators is the erratic and deplorably low quality of coal, having the following:|