SCR脱硝机组空气预热器堵塞治理建议

PROPOSALS FOR CONTROLLING AIR HEATER PLUGGAGE OF SCR DENITRATION UNITS

燃煤机组安装SCR脱硝装置后,空气预热器堵塞成为普遍现象,严重影响机组的安全性、经济性。通过对空气预热器堵塞物成分分析,提出治理空气预热器堵塞技术路线,结合实际运行中出现的问题,探寻SCR脱硝机组氨逃逸率高、SO_3浓度高、排烟温度低的原因,并且分析这些因素对空气预热器堵塞程度的影响,建议从保持催化剂活性,确保NO_x浓度,氨逃逸率均匀分布,防止氨过喷,降低入炉煤含硫量,提高锅炉排烟温度等方面,综合治理空气预热器堵塞,并提出详细的建议。

After SCR denitration device is installed on coal-fired unit,air heater pluggage becomes widespread. Air heater pluggage affects seriously the economy and safety of the unit. In the paper,the technical route of controlling air heater pluggage has been proposed by the component analysis of air heater pluggage materials. Causes of high NH_3 escape rate,high SO_3 concentration,low boiler exhaust temperature have been explored on the base of the problems occurring during actual operation. The influence of the factors on the extent of air heater pluggage has been analyzed. The paper proposes to maintain catalyst activity,ensure uniform distribution of NOxconcentration and NH_3 escape rate,prevent ammonia overspray,reduce sulphur content of fired coal, improve the boiler exhaust temperature, and so on, for the purpose of controlling comprehensively air heater pluggage.