选择性非催化还原烟气脱硝技术的研究现状与发展  

Research status and development of flue gas denitrification technology in selective non-catalytic reduction

作　　者：罗晨 马素霞 冯于川[1,2] 王春波 赵贯甲 冯浩 刘建伟[1] LUO Chen;MA Suxia;FENG Yuchuan;WANG Chunbo;ZHAO Guanjia;FENG Hao;LIU Jianwei(ShanXi Research Institute of Huairou Laboratory,Taiyuan 030032,Shanxi China;College of electrical and power engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi China;Jinneng Holding Power Group,Taiyuan 030006,Shanxi China)

机构地区：[1]怀柔实验室山西研究院,山西太原030032 [2]太原理工大学电气与动力学院,山西太原030024 [3]晋能控股电力集团有限公司,山西太原030006

出　　处：《电力科技与环保》2024年第6期603-614,共12页Electric Power Technology and Environmental Protection

基　　金：山西省科技重大专项“循环流化床复合燃烧快速调峰关键技术及工程示范”(202201090301001)。

摘　　要：选择性非催化还原(selective non-catalytic reduction,SNCR)脱硝技术广泛应用于燃烧后烟气NOx排放控制,尤其适用于循环流化床(circulation fluidized bed,CFB)锅炉烟气脱硝。SNCR技术工程应用的NOx脱除效率受到诸多因素的影响,现阶段CFB机组调峰运行期间烟温过低易导致SNCR脱除性能不佳。本文系统阐述了SNCR技术的研究现状与发展,分析了影响脱硝性能的主要工艺参数,对比了各新型还原剂与活性添加剂对脱硝效率的增效特性,总结了不同SNCR反应动力学模型的特点及模拟计算关键反应机理。CFB锅炉二次风口布置SNCR脱硝喷枪、喷枪错位布置及非定速雾化喷射等优化方式可一定程度提高脱硝效率;负载氨基还原剂、活性添加剂、助燃剂等的高分子固体脱硝剂具有显著的低温增效性能;亲水性添加剂(乙醇、乙酸、过氧化氢)与碱金属化合物(碳酸钠、氢氧化钠、乙酸钠)用于SNCR低温增效脱硝的工程应用前景良好;结合机理实验与反应动力学模拟计算可进一步探明SNCR微观反应机理,为该工艺的增效优化提供理论参考。Selective non-catalytic reduction(SNCR)denitration technology is widely used for NOx emission control of flue gas after combustion,especially for flue gas denitration of CFB boiler.The NOx removal efficiency of SNCR engineering application is affected by many factors,and the low flue gas temperature during the current CFB peakshaving operation leads to poor SNCR removal performance.The research status and development of SNCR technology were described,the main process parameters affecting denitrification performance were analyzed.The synergistic characteristics of various new reductants and active additives on denitrification efficiency were compared.The characteristics of different SNCR reaction kinetic models and key reaction mechanisms were summarized in this paper.Optimization methods such as arranging SNCR denitration spray guns at the secondary tuyere of CFB boiler,misplacing spray guns and non-constant speed atomizing injection can improve the denitration efficiency to some extent.Polymer solid denitration agent loaded with amino reducing agent,active additive and combustion improver has remarkable low-temperature synergistic performance.Hydrophilic additives(ethanol,acetic acid,hydrogen peroxide)and alkali metal compounds(sodium carbonate,sodium hydroxide and sodium acetate)have good engineering application prospects for SNCR low-temperature synergistic denitration.Combining mechanism experiments and reaction dynamics simulation calculation,the micro-reaction mechanism of SNCR will be explored and will provide theoretical reference for the synergistic optimization of this process.

关 键 词：选择性非催化还原 CFB锅炉 烟气脱硝 反应动力学 增效优化 

分 类 号：TK09[动力工程及工程热物理] X511[环境科学与工程—环境工程]