烟气深度余热回收技术对燃气锅炉NO_x排放扩散迁移规律的影响研究  

Effect of high efficiency heat recovery from flue gas on NO_x dispersion in a gas boiler

作　　者：张艳华[1,2,3] 宋光武[1,2] 罗志云[1,2] 闫静[1,2] 潘涛[1,2] 

机构地区：[1]北京市环境保护科学研究院,北京100037 [2]国家城市环境污染控制工程技术中心,北京100037 [3]首都师范大学资源环境与旅游学院,北京100048

出　　处：《环境科学学报》2016年第3期1064-1069,共6页Acta Scientiae Circumstantiae

基　　金：北京市科技计划项目资助(No.D14110900110000)~~

摘　　要：运用Fluent计算软件对北京市丰台区某燃气锅炉排放烟气中NOx的转化和扩散过程进行了数值模拟,定量地研究了烟气深度余热回收技术对燃气锅炉排放NOx在大气中的迁移规律产生的影响,并与Screen 3模型模拟的结果进行了对比.研究发现:烟气深度余热回收技术的应用使NOx的最大落地浓度与烟气直排时相比增加了2.5倍,NOx对本地地表的影响面积增大了15750 m2,增加了本地环境污染的风险.结合燃气锅炉的NOx控制技术提出了缓解局部环境风险的解决方案.结果表明,烟气深度余热回收技术与低氮燃烧技术联用,NOx的控制效率达到70%以上时,在有效提升锅炉热效率的同时,可以缓解由于烟温大幅下降造成的本地环境污染恶化的风险.The NOxemission transformation and dispersion process in a gas fired boiler in Fengtai District,Beijing was modeled and analyzed using the Fluent Computational Fluid Dynamics Software. The impact of high efficiency heat recovery technology on NOxemission from the flue gas was quantitatively investigated and compared with the simulated results from Screen 3 model. The results indicated that the maximum NOxconcentration at ground surface level increased by 2.5 times and the impacted area of ground surface enlarged about 15750 m^2 when a high efficiency heat recovery facility was applied to a boiler. To counteract the ground level pollution increase caused by heat recovery boilers,it was recommended that these boilers be paired with NOx pollution control devices such as low NOxburners. When the low NOxburners reduced NOxemission by 70% or greater,the combination of these two facilities not only reduced the risks of deterioration of the local environment,but also improved the thermal efficiency of the boiler.

关 键 词：余热回收 烟气扩散 NOx 数值模拟 低氮燃烧技术 

分 类 号：X701[环境科学与工程—环境工程]