The number of polluting processes inside the automobile assembly plant is limited. Painting, machining, finishing, incineration and the effluent treatment plant itself are the major sources of pollution. Energy is a major input, which causes pollution in the upstream processes involving generator, boiler, power plant and the like. Consumption of oil, lubricants, coolants and solvents contributes to the toxic and non-biodegradable pollutants from the plant.
In absolute terms the production facility of the automobile sector creates far less pollution than those of other manufacturing industries (pulp and paper, iron and steel and textiles). But grp found that its overall environmental performance leaves much to be desired.
Automakers draw 91. 3 per cent of their energy requirements from polluting fossil fuels such as coal, diesel and furnace oil. Only 8.7 per cent of the total energy consumed comes from liquefied petroleum gas (lpg), compressed natural gas (cng), propane and other such green fuels (see chart: Pollution at the plant ). Of the 26 concerns rated, 14 were seen using 100 per cent polluting fossil fuels. But encouraging trends have emerged over the past three years, pointing to a concerted effort by 75 per cent of the companies to cut their specific energy consumption.
The industry is not a major consumer of water and, therefore, does not seem to be addressing this problem seriously enough. Despite this, 62.5 per cent companies have decreased their specific water consumption. The concept of sourcing water through harvesting has not yet arrived in the sector across the globe. India is no exception. As much as 75 per cent of the total requirement is met from ground water.
Auto companies use a substantial portion of new metals in their casting operations (see chart: Pollution at the plant). Currently, only about 25 per cent of the metals used in foundry and aluminium dye-casting are recycled. Most manufacturers use 20-30 per cent scrap. This trend has been constant for the past three years.
Non-biodegradable metal working fluids and solvents are very commonly used in the assembly plant. Currently, few companies are recycling their lubricants. Tri-chloro-ethane, a solvent used for finishing operations and facility clean-up, is a known carcinogen and has been banned in the West. It is, however, commonly used in India. Another environmental problem is the disposal of grinding sludge. Most of the companies claim to be either storing this waste or selling it without any further follow-up. Though almost all the companies use components with heavy metal plating, monitoring of heavy metals in wastewater is not practiced in India. Heavy metals such as lead, tin and chromium are indispensable parts of a vehicle but extremely toxic. Prolonged exposure of workers to these can seriously affect their health.
The global paint industry is in the midst of a green revolution, but this makeover seems to have been overlooked by the Indian auto sector. Vehicle manufacturers continue to use solvent and heavy metal-based paints instead of water-based ones. The paint transfer efficiency of the Indian companies is less than 50 per cent, which means more than half the paints consumed go waste.
That the majority of them do not monitor volatile organic compound (voc) emissions is a cause for concern. voc is a major pollutant which can, however, be recycled for energy generation. This, too, is not being done. Manual painting, perceived to enhance the look of the vehicle, is still in vogue in the industry. Close to 50 per cent of the companies have recorded a surge in the use of paints and primers during the past three years.
A square peg in a round hole would succinctly sum up the state of wastewater management at the automobile production plants. Even as most of the wastewater discharged is chemical in nature, nearly all companies have installed biological treatment systems wherein sewage waste is mixed with process waste and then treated. The result: chemical dosing in the biological plant, causing acidification of wastewater. Regulatory standards in this context have been found to be lax and irrational. Segregation of wastewater in terms of level of pollution is also not undertaken.
The average efficiency of effluent treatment plants (etps) is 48 per cent. This indicates that the difference between pre-treatment and post-treatment wastewater quality is 48 per cent. The automobile sector has achieved a score of 39.7 per cent in water pollution.
If not monitored, incinerators can pose a problem themselves. No company has kept tabs on incinerator emissions as they seem content merely with its installation.
Several plants also have high capacity diesel generator sets. Here, too, no emission control devices are in place. The automobile industry has managed 30 per cent -- a dismal score -- in this category.
The absence of coherent norms to handle solid and hazardous wastes has resulted in the sector getting 25.5 per cent. Of the total solid waste generated, 48.30 per cent is land-filled, 2.3 per cent reused or recycled, 13.9 per cent is sold, 27 per cent is sold but end-use not kept track of and 8.5 per cent is incinerated.
Forty-six per cent of hazardous waste is land-filled, 10 per cent sold to contractors without any follow-up, while approximately 45 per cent is incinerated and emissions not monitored.
Despite delegating most of the polluting processes to vendors, the overall environmental performance of the automobile companies at the production plant has been far from satisfactory. Remedial action -- both short-term and long-term -- is the need of the hour.
Vehicle manufacturers should switch over to clean gaseous fuels such as lpg and cng to meet their energy needs at the plant.
With vast tracts of land at their disposal, rainwater harvesting can be a viable alternative to cater to their process water requirements.
Recycling can help reduce the use of new metals in their casting operations.
Automakers should opt for water-based paints instead of solvent and metal-based ones.
It is not enough for companies to instal pollution control devices such as incinerators. A close watch must also be kept on the emission caused by them.
Authorities should lay down proper norms for solid and hazardous waste disposal, clearly stressing the importance of reuse and recycling.
On the whole, the automobile sector needs to look afresh at the issue. Prevention rather than cure can help nip production-stage pollution in the bud.