CHECK any restaurant in northern India; the chances are you'll find the name Palam Potteries on their plates and cups. Since 1955, this plant, located near the India Gandhi airport in New Delhi, has supplied its ware to restaurants and hotels. But the threat of relocation forced the management to first go in for pollution control and later, waste minimisation.

Smoke from the firings of earthenware in the vicinity of the airport amounted to a major "crime". In 1965, the authorities declared their intention to extend the airport over an area that included the factory. But the plan was quashed by the local court.

Later, the authorities told Palam Potteries they were a non-conforming industry and would have to move elsewhere. Simultaneously, the Delhi pollution control committee (DPCC) issued a notice to the company, alleging they were polluting well in excess of the prescribed limit of 1,200 micrograms/cum.

Says joint managing director O P Joshi, "We were emitting some 5,000 micrograms/cum at the time." The authorities had also appealed to the lieutenant governor of Delhi to have the factory shifted because its proximity to the airport posed a hazard for aeroplanes.

Desperate search
Under pressure, Palam Potteries searched desperately for a way out. DPCC took the company to court and after a lower court ruled against Palam Potteries, they appealed to the Delhi High Court. In the course of the proceedings, they made a plea for help to find an answer to their solution and, through a legal friend, got in touch with a "consultant" whose name Joshi does not care to remember.

The consultant studied the plant's pollution problems for a week, but the solution he prescribed proved useless. By now, the Delhi administration was threatening the plant with closure.

In late 1990, Joshi heard about NPC's environmental consultancy cell and called K P Nyati, who is now environment adviser to the Confederation of Indian Industry. NPC's team studied the plant process for three months and came up with a simple, cost-efficient solution. The scientists found the firing cycle of the plant, spread over 42 hours, produced varying quantities of smoke. As the quantity of coal was increased to raise temperatures inside, the quantum of smoke emitted also rose. A cyclone connected to the chimney sucked air out of the kiln and chimney. The smoke, says Nyati, was nothing but unburnt carbon particles.

The solution rested around finding a more efficient way to burn coal and the cyclone itself provided the answer. By drawing out the air through the kiln, the fan in the cyclone increased combustion efficiency to a point. Beyond that, it reduced temperatures inside, with a fall in the quality of the ware.

Therefore, there was a need to control the airflow generated by the cyclone's fan, which was met by putting a butterfly, a device much like that found in carburetor chokes, inside the pipes taking air from the chimney to the fan. By varying the butterfly's pitch, the operator could control the quantum of air passing through the furnace.

Palam Potteries benefitted in two ways -- coal consumption decreased by 16 per cent, which helped it recoup the Rs 3.5 lakh spent on the cyclone, and emissions reduced to below prescribed limits.

But the greatest gain was the firm could now rebut the charge that it was a hazard to aircraft in the area. "We could turn around and show DPCC and the Delhi administration that we were meeting the prescribed norms and that they could no longer call us a polluting industry," says Joshi.

Palam Potteries has since switched to oil-fired furnaces that are totally non-polluting and produce better ware, though they are more expensive than coal-fired kilns.