RESEARCH ARTICLE

Effect of circulating ash from CFB boilers on NO and N2O emission

  • Xiangsong HOU , 1 ,
  • Shi YANG 2 ,
  • Junfu LU 2 ,
  • Hai ZHANG 2 ,
  • Guangxi YUE 2
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  • 1. Utilities Engineering Department CISDI Engineering Co., Ltd., Chongqing 400013, China
  • 2. Department of Thermal Engineering, Tsinghua University, Beijing 100084, China

Received date: 01 Jul 2008

Accepted date: 16 Aug 2008

Published date: 05 Jun 2009

Copyright

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg

Abstract

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.

Cite this article

Xiangsong HOU , Shi YANG , Junfu LU , Hai ZHANG , Guangxi YUE . Effect of circulating ash from CFB boilers on NO and N2O emission[J]. Frontiers in Energy, 2009 , 3(2) : 241 -246 . DOI: 10.1007/s11708-009-0006-0

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