摘要
为了解燃煤锅炉变温条件下甲烷对选择性非催化还原(selective non-catalytic reduction,SNCR)方法脱硝性能的影响,考察了4种化学反应模型的适用性,在此基础上,选择了能较好反映出低温、长停留时间下SNCR效果的AA模型,计算了变温工况下不同甲烷喷入量对NO脱除效率的影响。结果表明,喷入RCH4(CH4与NO的体积分数之比)=0.5～2.0的甲烷可显著降低SNCR过程中NO与NH3发生反应的温度,提高NO脱除效率;考虑到CH4和CO的不完全燃烧,RCH4=0.5是较适宜的甲烷添加比例,过高CH4喷入量将导致CO排放增加,成为限制NO脱除效率的瓶颈。
Four reaction models of the SNCR （selective non-catalytic reduction） process were used to study the effect of variable flue gas temperatures on NO removal. The AA model, which simulates the SNCR performance well at low temperatures and longer residence times, was selected to analyze the effect of additional CH4 on the NO removal. The addition of CH4 with CH4 to NO volume fraction ratio of 0. 5 -2.0 lowers the NH3 and NO reaction temperature, removes more NO. Take into account the incomplete combustion of CH4 and CO, the CH4 to NO volume fraction ratio of 0. 5 is optimal since excessive CH4 would increase CO emissions which limit NO removal.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2008年第8期1315-1320,共6页
Journal of Tsinghua University(Science and Technology)
基金
国家"九七三"重点基础研究项目(2006CB200301)
