水泥窑烟气SNCR脱硝技术喷射系统的关键问题  

Key problems of cement kiln flue gas SNCR denitration technology injection system

作　　者：张立娟[1] 凌绍华[1] 

机构地区：[1]中国环境管理干部学院环境工程系,秦皇岛066004

出　　处：《环境工程学报》2015年第5期2373-2378,共6页Chinese Journal of Environmental Engineering

基　　金：河北省科学技术研究与发展计划项目(12273701);秦皇岛市市级科技计划项目(201401A006;201401A233)

摘　　要：喷射系统是水泥窑烟气SNCR脱硝技术的重要组成部分,对日产5 kt新型干法水泥烟气SNCR脱硝项目中的喷射系统进行了设计和实验研究。结果表明,系统压力设计、分配调节设计、喷枪布置和喷枪雾化能力是影响烟气脱硝效率的关键因素。在氨水质量分数为13.5%,喷入点温度904℃,n(NH3)/n(NH3)为1.2条件下,系统压力能够稳定运行在0.3~0.6 MPa之间、喷枪雾化颗粒度平均直径在50μm左右、喷枪在分解炉上的垂直安装角度为75°时烟气NOx浓度由原来的720 mg/Nm3降低到206 mg/Nm3,脱硝效率能达到70%,远低于水泥工业大气污染物排放标准的限定要求。对同类新型干法水泥熟料生产线SNCR脱硝技术有一定的参考意义。Injection system is an important part of cement kiln flue gas SNCR denitration technology. The design and experimental study on injection system were carried on the 5 000 t / d new dry process cement flue gas SNCR denitration project. The denitration efficiency turns on four key factors that are the system's pressure design,distribution regulation design,denitration lance layout and atomization ability. Under the conditions of ammonia mass fraction of 13. 5%,injection point temperature of 904℃,n( NH3)∶ n(NOx)of 1. 2. When the system pressure run stably in 0. 3 ~ 0. 6 MPa,the spray atomization particle average diameter was about 50 μm,and the lance in the decomposition furnace vertical installation angle was 75 °,the flue gas NOxconcentration decreased from 720 mg / m3 to 206 mg / m3. The denitration efficiency reached 70%,far below the emission standard of air pollutants for cement industry. It has some reference meaning on similar new dry cement clinker production line of SNCR denitration technology.

关 键 词：水泥窑 烟气脱硝 喷射系统 关键因素 

分 类 号：X781.5[环境科学与工程—环境工程]