SCR脱硝在燃煤电厂超低排放中的适用性分析  

Applicability analysis of SCR technology to ultra-low NO_x emission for coal-fired power plants

作　　者：庄烨[1] 张东辉[1] 褚玥[1] 松鹏[1] 

机构地区：[1]北京国电龙源环保工程有限公司,北京100039

出　　处：《环境工程学报》2017年第7期4183-4189,共7页Chinese Journal of Environmental Engineering

基　　金：国家科技支撑计划项目(2015BAA05B01)

摘　　要：通过流场模拟、化学动力学计算、并结合物理实验,全过程研究SCR反应器内烟气组分的动量/能量/质量传递及脱硝还原反应,计算在不同入口NO_x浓度下SCR出口NO_x和氨逃逸的排放量及空间分布,确定SCR在NO_x超低排放要求下的适用范围。研究结果表明,为实现NO_x<50 mg·Nm^(-3)并同时满足NH_3<2.28 mg·Nm^(-3)的要求,2层SCR催化剂可处理的入口烟气NO浓度上限为240 mg·Nm^(-3),而3层SCR催化剂则可对NO浓度<380 mg·Nm^(-3)的烟气实施超低排放治理,为合理选择SCR超低排放设计方案提供了数据支撑。Fluid simulation, chemical kinetics calculation, and cold flow experiments were performed to characterize momentum-mass-energy transfer of flue gas constituents and de-NO, reaction within an SCR （selective catalytic reactor）. Partition of NO and NH3 in the flue gas and their emissions at the SCR outlet were calculated, at varied inlet NOx concentrations, to determine the applicability of SCR technology to ultra-low emission of NOx （ 〈 50 mg · Nm-3 ） for coal-fired power plants. Research results indicate that a two-layer SCR can reduce NO, emis- sion to 〈50 mg · Nm-3 , with ammonia slip 〈2.28 mg· Nm-3 , for a coal flue gas containing 240 mg· Nm-3 of NO or less. The upper limit for a three-layer SCR to achieve the same level of SCR performance would be 380 mg · Nm-3 NO. These results serve as a design guideline to achieve a cost-effective strategy for achieving ultra-low NOx emission at coal fired power plants.

关 键 词：燃煤烟气 SCR NOx 超低排放 氨逃逸 

分 类 号：TQ028.2[化学工程]