循环流化床锅炉SNCR脱硝系统优化及应用  

SNCR denitrification system in CFB boilers:optimization and application

作　　者：屈卫东[1] 周建强[1,2] 杨建华[1] 秦光耀[1] 

机构地区：[1]郑州电力高等专科学校动力工程系,河南郑州450004 [2]华北电力大学能源动力与机械工程学院,北京102206

出　　处：《热力发电》2014年第1期133-136,共4页Thermal Power Generation

摘　　要：根据循环流化床（CFB）锅炉的特点,对以尿素为还原剂的选择性非催化还原（SNCR）脱硝系统进行了优化设计.通过数值模拟,发现在分离器入口段上侧和内侧喷入还原剂脱硝效率较高;把尿素溶液制备浓度由50％改为10％,系统可以取消伴热系统;采用计量泵控制小流量还原剂溶液更精确.优化后的脱硝系统在某电厂4×130 t/h的CFB锅炉进行了应用,测试表明,在NOx原始排放浓度为120～130 mg/m3时,脱硝效率达50％以上,建设成本和运行成本分别为32、0.001 45元/（kW·h）.According to the characteristics of on selective non-catalytic reduction （SNCR） circulating fluidized bed （CFB） boilers denitrification system applying urea as , optimization the reducing agent was conducted. Numerical simulation results indicate that, spraying the injecting reducing a- gent from the upper side of the separator inlet to the inner side can result in higher reducing a- gent＇s efficiency;decreasing the urea solution concentration from 50% to 10% ,the SNCR system can be operated without heat tracing system; the metering pump can make the flow rate control more accuracy for the reducing agent solution with small flow rate. The optimized SNCR system was applied in four 130 t/h CFB boilers of a power plant. The measurement shows that,denitrifi- cation efficiency of the SNCR system reaches up to more than 50% ,when the orignial NOx emis- sion ranges from 120 mg/m3 to 130 mg/m3,and the construction cost and operation cost of the system are only 32 yuan/kWh and 0. 145fen/kWh,respectively.

关 键 词：CFB锅炉 SNCR 尿素 还原剂 脱硝效率 

分 类 号：X511[环境科学与工程—环境工程]