Measurements of N₂O Emission from Stationary Sources and Studies on the Formation

Abstract

We meausred N₂O of exhaust gas from 9 stationary sources. As the results, N₂O concentrations from the gas boilers were very low and less than about 5 ppm, even then low excess air ratio. In case of municipal refuse incinerator, the concentrations were the extent of several 1-20 ppm. And the amount of N₂O from refuse incinerators was about 70g per 1 ton municipal refuse. The total emission from muiucipal refuse incinerator in Japan is estimated to be about 2, 400 ton a year.
In case of sewage sludge incinerator, N₂O concentration of exhaust gas was the extent of several tens-100ppm and more than NO on the contrary. And the amount of N20 from sludge incinerators was about 400g per 1 ton sludge cake. The total emission is estimated to be about 1, 240 ton a year in the same way as the above plant.
Subsequently we surveyed the formation of N₂O on the various conditions by using a laboratory combustion apparatus. It became clear that N₂O depended on N content in kerosene. At gas burning test, N₂O formation was very low level.