The Estimation of Emission Factor of N2O and CH4 by Measurement from Stacks in the Waste Incinerators and Cement Production Plants

The Estimation of Emission Factor of N2O and CH4 by Measurement from Stacks in the Waste Incinerators and Cement Production Plants

The purpose of this study is to estimate the emission factor of non-CO2 global warming gases such as N2O and CH4 by measuring concentrations from stacks of waste incinerator and cement production plants. Based on the established monitoring methods, N2O concentration measured from stacks in incinerator were between 0.62 and 40.60 ppmv (ave. 11.50 ppmv). The concentration of N2O was dependent on theincinerator types. However, the concentration of CH4 gas were between 2.65 and 5.68 ppmv (ave. 4.22 ppmv), and did not show the dependency on the incinerator types. In the cement production plant, the concentration ranges of N2O from the stack were from 6.90 to 10.80 ppmv (ave. 8.60 ppmv), andCH4 were between 1.80 and 2.20 ppmv (ave. 2.60 ppmv). Using measured concentrations, the emission amounts of N2O and CH4 from stacks per year were calculated. The results were is 4.2 ton N2O/yr in the incinerators, and 53.7 ton N2O/yr in the cement facilities. The big difference is from the flow rate of flue gas in the cement facilities compared to the incinerators. By the same reason, the CH4 emission amounts in cement plant and incinerator was found to be 339 ton CO2/yr and 34.1 ton CO2/yr,respectively. Finally, the emission factor of N2O in the incinerators were calculated using the measured concentration and the amount of incinerated wastes, and was 42.5~799.1 g/ton in kiln and stoker type, 11.9~79.9 g/ton in stoker type, 90.1 ton/g in rotary kiln type, 174.9 g/ton in fluidized bed type, and 63.8 g/ton in grate type, respectively. Also, the emission factors of CH4 were found to 65.2-91.3 g/ton in kiln/stoker type, 73.9-122 g/ton in stoker type, 109.5 g/ton rotary kiln, and 26.1 g/ton in fluidized bed type. This result indicates that the emission factor in incinerators is strongly dependent on the incinerator types, and matched with result of IPCC (International Panel on Climate Change) guideline.