添加煤气化合成气的SNCR脱硝反应实验与机理研究  

Study on Experiment and Mechanism of Selective Non-catalytic Reduction with Coal Syngas as an Additive

作　　者：李德龙[1] 杨梅[1] 于娟[1] 张忠孝[1] 

机构地区：[1]上海交通大学机械与动力工程学院

出　　处：《电站系统工程》2014年第3期5-8,11,共5页Power System Engineering

基　　金：国家科技支撑计划子课题(2012BAA02B01-05)

摘　　要：新国标对氮氧化物（NOx）的排放有了更严格的限值,利用煤气化合成气作为选择性非催化还原反应（SNCR）的添加剂可以显著改善氮氧化物的脱除效果。选择两种典型的气化合成气作为SNCR反应的添加剂,对其过程进行了理论分析和实验研究,同时对脱硝机理进行了简化。结果表明合成气可以有效地提升SNCR反应脱硝的效果：添加900ppm合成气时,合成气1#的最佳温度窗口约为780℃,温度区间为710-940℃,合成气2#的最佳温度窗口约为770℃,温度区间为730-890℃,窗口较为窄小,两种合成气与无添加剂的SNCR反应相比,最佳反应温度降低了约150℃,脱硝效率约提升8个百分点;最适反应温度随着浓度的降低呈现升高趋势;最高脱硝效率均可以达到80%;合成气1#作为添加剂的总体脱硝效果略优于合成气2#。同时,简化出的包含33种物质,99个反应的机理模型与复杂反应模型结果符合较好,计算速度可以提升4倍以上,可以预测出反应情况。The new national standards have more stringent limits on nitrogen oxide（NOx） emissions. Coal gasification syngas as an additive of selective non-catalytic reduction（SNCR） can improve the NOx removal efficiency significantly. In this study, two typical kinds of gasification syngas were chosen as additives and theoretical analysis and experimental research were carried out, while denitrification mechanism was simplified. The results showed that the syngas could effectively enhance the effect of SNCR. With two kinds of syngas of 900ppm, the optimum temperature window for 1# would be about 780℃ and the temperature range would be 710℃-940℃, while for 2# the window would be about 770℃and the range would be 730℃-890℃, a relatively narrower window. Compared to reactions with no addictive, the optimum temperature window shifted down about 150℃ and maximum removal efficiency shifted up about 8 percent, for both syngases. With concentrations of additives decreasing, the optimum reaction temperature showed an increasing trend. It would be slightly better for syngas 1# as an additive than syngas 2#. For all of the above, maximum removal efficiency could reach 80%. At the same time, simplified model contained 33 kinds of substances and 99 reactions. Computing speed would increase by more than 4 times. The results of the model, which agreed well with that of complex reaction model, could well predict conditions of SNCR.

关 键 词：NOx 合成气 选择性非催化还原反应 机理简化 

分 类 号：X701.3[环境科学与工程—环境工程]