“Options to...”

There is no way the world can do without incinerators and crematoria. Noshir H. Dadrawala says London, Munich and Los Angeles use incinerators at their peril ("Options to...” Readers’ Forum, Parsiana, April 2003). What peril is Dadrawala talking about? The world’s garbage is increasing by leaps and bounds and the USA leads the world with 2.1 kg household refuse per person per day. For urban centers like New York or San Francisco the daily refuse could be as high as five kilos per person per day. Land-filling and dumping sites are becoming scarcer and incinerators, besides generating power, cause a 90 percent reduction in volume of the garbage and a 40 percent reduction in weight. They are the only alternative, and there are scores of incinerators operating around the world today.

Years ago I had asked the then assistant municipal commissioner (AMC) in charge of waste disposal and management why incinerators were not installed in Bombay for disposal of over 3,000 tons of garbage per day. Today the figure may be even 5,000 tons/day. The AMC’s reply was that for four months during the monsoons from June to September the incinerator would become totally inoperational due to the high moisture content of the garbage. This would hinder self-sustained combustion in the incinerator. The same problem is being faced at Doongerwadi where the solar reflectors become totally in operational during the monsoon on account of rains and cloudy skies. It takes four to five days to dry the body even in dry weather.

According to the latest information, the Maharashtra Energy Development Agency (MEDA) has planned a dozen power generation plants based on bio-mass wastes in the drier regions of the state starting with Gondia. Such power plants based on biomass wastes are already operating in Andhra and Karnataka (The Indian Express, March 2, 2003).

On the question of crematoria, a 1991 survey in Britain had indicated that 70 percent of the dead preferred cremation as against 30 percent for burial in cemeteries, essentially because cremation is the most sanitary and efficient method for the disposal of the dead.

Coming now to the pollution aspect of incinerators, the effluents from incinerators and crematoria have to conform to the Environmental Protection Acts of the local bodies. It has been established experimentally that if the gases in the chamber are held for two seconds at 850°C, it is sufficient to destroy any hazardous and toxic gases in the effluents. Dadrawala talks about some initiatives taken by the American Lung Association to ban incinerators. How do the lungs come into the picture? The lungs are all at ground level whereas the chimneys from incinerators and crematoria dissipate the effluents high above the rooftops and the high velocity causes dispersion of the effluents into the atmosphere at a much higher altitude.

Whatever little dioxins that Dadra-wala talks about comes from the exhaust of diesel vehicles, but with the enforcement of the Euro-I and the Euro-II norms essentially for the suppression of SPM (Suspended Particulate Matter), Nox and SO2 and the gradual change over of diesel cars to CNG and LPG, this aspect is also taken care of.

In one of his earlier articles, Dadra-wala referred to crematoria causing the warming of the planet by the greenhouse effect due to accumulation of carbon dioxide (CO2) in the atmosphere. Actual studies in the UK in 1991 had indicated that the contribution by crematoria to CO2 was only 0.01 percent, the rest being contributed by thermal power stations, automobiles and from combustion of fuels in boilers for centrally heated buildings and private domestic homes.

Dr P. D. SUNAVALA