300MW燃煤锅炉SNCR过程的数值模拟  

Numerical simulation of SNCR in a 300MW pulverized-coal boiler

作　　者：姜敏[1] 金保昇[1] 周英贵[1] 王晓佳[1] 

机构地区：[1]东南大学能源热转换及其过程测控教育部重点实验室,南京210096

出　　处：《东南大学学报（自然科学版）》2012年第4期691-695,共5页Journal of Southeast University：Natural Science Edition

基　　金：科技部中欧国际合作资助项目(2010DFA61960)

摘　　要：利用FLUENT软件对300 MW燃煤锅炉的选择性非催化还原(SNCR)过程进行了模拟.重点分析尿素溶液的喷射位置、液滴喷射速度、雾化平均粒径对SNCR过程脱硝效率以及漏氨量的影响,从而得到实际运行过程中最佳运行条件.结果显示,增加喷射速度能加快蒸发过程;雾化粒径越大越有利于还原剂的平均分布,但也会延长蒸发时间;在第1,2层同时喷射尿素溶液,并控制雾化平均粒径为0.3 mm和液滴喷射速度为30 m/s时,能够获得较好的脱硝效果.将不同氨氮摩尔比模拟结果与实际过程进行对比,结果表明两者能够较好地吻合.Modeling and numerical simulation for SNCR（selective non-catalytic reduction） in a 300MW pulverized-coal boiler were conducted based on the FLUENT software.Main factors including the injection position of urea-solution,droplet velocity,droplet size and their influence on NOx removal efficiency and ammonia slip were analyzed,thus the best operational conditions were obtained.The results indicate that increasing the injection speed can accelerate the evaporation process.The greater the droplet size is,the better the reductant distributes,and the longer the evaporation time is.Injecting urea-solution on both the first and second floor with a mean atomizing particle size of 0.3mm and a velocity of 30m/s shows an ideal result.Simulation and measured values under different molar ratios of NH3/NO are compared,which shows a good agreement.

关 键 词：数值模拟 选择性非催化还原 雾化 氮氧化物 

分 类 号：X511[环境科学与工程—环境工程]