CIESC Journal ›› 2013, Vol. ›› Issue (5): 1789-1796.doi: 10.3969/j.issn.0438-1157.2013.05.039

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Simulation and optimization of SNCR process

LI Qiong, WU Yuxin, YANG Hairui, LÜ Junfu   

  1. Key laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084, China
  • Received:2012-08-04 Revised:2012-11-24 Online:2013-05-05
  • Supported by:

    supported by the Key Project in the National Science & Technology Pillar Program(2012BAA02B01)and the National Natural Science Foundation of China(51076081).

Abstract: Using computational fluid dynamics(CFD)method,the urea-based selective non-catalytic reduction(SNCR)process in a 100 t·h-1 circulating fluidized bed(CFB)boiler was numerically simulated to study effect of temperature and normalized stoichiometric ratio(NSR)on SNCR denitration efficiency, NH3 slip and N2O formation.The results show that the window of optimized temperature for SNCR process is in a range of 850-1050℃ and becomes wider with increasing NSR; when temperature rises, NH3 slip decreases obviously and can be ignored if temperature is higher than 940℃.With increase of temperature, amount of N2O formation increases first and then decreases.With increasing NSR, the denitration efficiency and NH3 slip increase.The denitration efficiency is the maximum at 980℃.Formation of N2O is in proportion to denitration efficiency and the maximum about 30 μl·L-1.

Key words: SNCR, temperature window, NSR, NH3 slip, CFD

CLC Number: 

  • X5
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