NO and N2O emissions from circulating fluidized bed (CFB) boilers are determined by their formation and destruction rates in the furnace. The effect of circulating ash from a CFB boiler on NO and N2O emissions were investigated in a laboratory-scale fluidized bed reactor. The results show that the residue char in circulating ash and the CO generated from the char play an important role in NO reduction and N2O formation; however, active components of circulating ash such as CaO, Fe2O3 accelerate the decomposition of N2O. Experiment was also conducted on a 75 t/h CFB boiler fueled with the mixture of anthracite and biomass. The lower residue carbon content of circulating ash in this experiment is lower; therefore, the reacting rate of NO deoxidize is limited. This result verified the conclusion of laboratory research.
. Effect of circulating ash from CFB boilers on NO and N2O emission[J]. Frontiers of Energy and Power Engineering in China, 2009, 3(2): 241-246.
Xiangsong HOU, Shi YANG, Junfu LU, Hai ZHANG, Guangxi YUE. Effect of circulating ash from CFB boilers on NO and N2O emission. Front Energ Power Eng Chin, 2009, 3(2): 241-246.
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