摘要
为解决锅炉氮氧化物排放浓度高的问题,对利港电厂1台370 MW机组前墙旋流燃烧器锅炉进行了燃烧器低氮改造。改造包括更换新型的中心给粉低NOx燃烧器和在后墙增加燃烬风喷口,改造后因为运行情况不理想,又经过了增加内二次风量套筒挡板和改进一次风喷口的二次优化改造,经过优化改造后氮氧化物排放的质量浓度有较大幅度的下降,平均降幅为42.35%,同时也解决了锅炉严重结渣、掉渣的问题,与此同时过热器减温水率也有一定幅度的下降,配合SCR脱硝的改造,达到了国家最新排放标准要求。存在问题是改造后锅炉飞灰含碳的质量百分数有相对较大幅度的升高,水冷壁区域还原性气体浓度过高,高温腐蚀的危险性较大。
In order to reduce the high NOx for a 370 MW front wall fired unit in Ligang power plant, the low NOx burner retrofit has been implemented. The retrofit includes a central concentrated LNB and rear wall OFA. The performance was not ideal after the first retrofit. Then the second retrofit was performed including new inner SA damper and modified PA nozzle. After the second modification, NOx is reduced by 42. 35%, and at the same time the serious problems such as dregs slagging and falling are solved, and the super heater spray flow is reduced to a certain degree. With the help of SCR, this unit can meet the government newest emission standards. The shortages are that the UBC increases significantly, the local reducing gas concentration near the wall area is higher and the risk of high temperature corrosion is larger after the retrofit.
出处
《电力科学与工程》
2014年第12期24-29,共6页
Electric Power Science and Engineering
