N2O emission factors in bubbling fluidized bed incineration of municipal sewage sludge: The China case

• Published in: Waste management (Elmsford) Vol. 183; pp. 253 - 259
• Main Authors: Dong, Yuhang, Wang, Lihua, Wang, Fei, Zou, Boyuan, Lv, Guojun, Cui, Haibin, Ye, Zhirong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 30.06.2024
• Subjects: Continuous monitoring; Emission factor; Greenhouse gas; Sludge incineration facility; SNCR; Emission factor; Continuous monitoring; SNCR; Greenhouse gas; Sludge incineration facility
• ISSN: 0956-053X; 1879-2456; 1879-2456
• DOI: 10.1016/j.wasman.2024.05.022

[Display omitted] •The deviation of N2O emission factor (EF) from short-term monitoring can reach 20%.•The N2O EF for sludge incineration in China may be smaller than the default value.•The N2O EF decreases as the temperature in the furnace increases.•The N2O EF of the sludge incinerators with smaller heat loads fluctuates more.•The fluctuation range of the N2O EF narrows with the increase of temperature. The N2O emissions resulting from sludge incineration are estimated using the default values published by the Intergovernmental Panel on Climate Change (IPCC), which may differ significantly from the actual emissions. In this investigation, N2O emissions from four sludge incineration lines in two plants were monitored for varying durations. The variation in N2O emission factors (EFs) between incineration lines of the same plant was much smaller than the difference between different plants. Data on N2O EFs obtained from brief monitoring may contain variabilities of up to 30%. N2O EFs were more sensitive to temperature changes at low temperatures, necessitating extended monitoring periods to improve the reliability of N2O monitoring outcomes in cases of low furnace temperatures. Excessive use of the SNCR system to reduce NOx emissions resulted in concentrations of N2O and NH3 in the exhaust gases exceeding NOx levels. In the case of furnace temperature control and advanced reburning technology, it is advisable to utilize actual monitoring data or the smaller default values provided by the IPCC in China. Otherwise, the estimated N2O emissions may exceed the actual emissions.