200 MW机组SCR烟气脱硝系统优化运行

Optimal operation of SCR flue gas denitration system of 200 MW unit

为缓解空气预热器ABS堵塞问题,研究以某200 MW机组为例,针对机组长时间处于深度调峰状态下烟气波动较大、烟气温度较低、喷氨量过高、多次发生空气预热器堵塞的问题。通过开展现场试验摸底,结合机组DCS历史数据,分析机组实际运行状况,确定空气预热器堵塞原因。根据试验结果对SCR烟气脱硝系统喷氨部分进行优化调整,消除了SCR烟气脱硝系统喷氨过量的现象,减少氨逃逸、延缓ABS的产生、缓解空气预热器堵塞的问题。

In order to alleviate the problem of ABS blockage in air preheater,taking a 200 MW unit as an example,the study aims to address the problems of large fluctuations in flue gas temperature,high ammonia injection volume,and repeated blockage of air preheater after the unit has been in deep peak shaving state for a long time.Through conducting field tests and combining with historical data from the unit's DCS,the actual operating conditions of the unit are analyzed to determine the cause of air preheater blockage.Based on the test results,the ammonia injection part of the SCR flue gas denitrification system is optimized and adjusted,eliminating the phenomenon of excessive ammonia injection in the SCR flue gas denitrification system,reducing ammonia escape,delaying ABS generation,and alleviating the problem of air preheater blockage.