340MW机组锅炉水冷壁高温腐蚀原因分析及治理

Reason Analysis and Treatment of High Temperature Corrosion on Water Wall of 340MW Unit Boiler

国家能源集团丰城发电有限公司双尺度低氮燃烧技术改造以来,锅炉水冷壁逐步暴露出高温腐蚀问题,因高温腐蚀引起的爆管占锅炉四管爆漏的50%以上。通过分析,煤质高硫份、切圆偏斜、运行氧量不足等是引起高温腐蚀的主要成因,制定了切圆调整、金属喷涂等防范措施。治理后,H2S浓度明显降低,高温腐蚀得到有效缓解,设备可靠性明显提高,减少了机组非计划停运的次数。

After the technology transformation of double scale low-nitrogen combustion of Fengcheng Powergeneration Co.,Ltd.of National Energy Group,the boiler water wall has gradually exposed the problem of high temperature corrosion,and the pipe burst caused by high temperature corrosion accounts for more than50%of the boiler four pipe leakage.Through the analysis,the main causes of high temperature corrosion are high sulfur content of coal,slanting of cutting circle,insufficient oxygen content in operation,etc.and preventive measures such as cutting circle adjustment and metal spraying are formulated.After the treatment,the concentration of H2 S was significantly reduced,the high temperature corrosion was effectively alleviated,the equipment reliability was significantly improved,and the number of unplanned outage of the unit was reduced.