Concentration of carcinogenic substances in flue gases with combustion of gas and oil

Sources of carcinogenic substances entering the atmosphere are different fuel-using plants, including steam generators of heat and power plants and of central power stations, internal combustion engines, and especially large quantities of carcinogenic substances are formed with dry distillation of fuel under conditions of pyrolytic reactions. At present one can maintain that carcinogenic substances entering the environment are products of combustion and use of fossil fuels. Despite the variety of carcinogenic substances forming with combustion their presence in combustion products and in the air is normally estimated according to the existence of benzopyrene, C/sub 20/H/sub 12/. C/sub 20/H/sub 12/ is regarded as an indicator of the presence of carcinogenic substances in the air, in combustion products, water, soil etc, since it is the strongest carcinogenic substance most common in the environment and easily detected by the characteristic spectrum of fluorescence. Comparison of data obtained with combustion of gas and oil in steam generators shows that, other conditions being similar, change of steam generators to operation on gaseous fuel makes it possible to decrease discharge of C/sub 20/H/sub 12/ by a factor of tens or more.