二次风喷嘴角度对炉排式垃圾焚烧炉内燃烧及选择性非催化还原脱硝的影响  

Effects of secondary air injection angle on combustion and SNCR performance in MSW incinerators

作　　者：李坚[1] 夏梓洪[1] 吴亭亭[1] 陈彩霞[1] 张小可 

机构地区：[1]华东理工大学煤气化及能源化工教育部重点实验室,上海200237 [2]上海环境集团,上海200040

出　　处：《环境工程学报》2016年第10期5907-5913,共7页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(21276085);上海市科委科技攻关计划重大项目(10DZ1200105)

摘　　要：利用CFD技术,对某城市处理量为750 t·d^(-1)的垃圾焚烧炉内燃烧与选择性非催化还原脱硝(SNCR)过程进行建模分析,重点研究了二次风喷嘴角度的改变对焚烧炉内燃烧温度场的影响及其对提高SNCR脱硝效率的作用。模拟结果表明,焚烧炉二次风喷嘴角度调整为相互交叉45°,可以改善炉内燃烧状况,促进炉膛内烟气与空气的混合,使炉膛内温度场分布均匀,有利于SNCR还原反应;二次风喷嘴角度改变后,在一定程度上保证了SNCR系统喷入的尿素液滴在炉膛内的停留时间。与平行二次风相比,使用交叉二次风送风方案,前墙喷嘴脱硝效率提高4.8%,后墙喷嘴脱硝效率提高了19.7%。A computational fluid dynamic（ CFD） technique was applied to the modeling and simulation of municipal solid waste（ MSW） combustion and the selective non-catalytic reduction（ SNCR） process in a 750t·d-1moving-grate incinerator. The effects of the varying secondary air injection angles on the temperature field were simulated,and their impacts on the De-NOxefficiency of the SNCR process were investigated numerically.The results showed that secondary air with a 45° cross-angle injection can improve the gaseous mixing and contribute to a uniform distribution of the gas temperature suitable for the SNCR performance. Compared with parallel injections of the secondary air,a proper change of the injection angles results in a longer residence time of the urea in the furnace,as well as a corresponding higher De-NOxefficiency. In detail,the De-NOxrates increased by 4. 8% and 19. 7% for the front and rear wall injections,respectively.

关 键 词：二次风 喷嘴角度 焚烧炉 SNCR 数值模拟 

分 类 号：X705[环境科学与工程—环境工程]