660 MW锅炉水冷壁高温腐蚀原因分析及应对措施

某厂锅炉水冷壁发生高温腐蚀现象,通过煤质分析、腐蚀形貌观察和腐蚀产物分析等方法研究了导致腐蚀的原因。结果表明:产生高温腐蚀的主要原因为机组实际燃煤硫分含量较设计偏高,燃烧器设计缺陷导致炉内强还原性气氛和定期的大出力试验使大量煤粉聚集粘结在水冷壁鳍片附近造成的。为此,提出了调整煤粉细度,燃烧器局部改造,燃烧优化调整等建议。

Causes Analysis and Solutions of High Temperature Corrosion of 660 MW Station Boiler Water Walls

In this paper,the causes of high temperature corrosion of water wall were studied through analysis of coal quality,corrosion morphologies and compositions.Results showed that the main reason for the high temperature corrosion was the higher sulfur amount in the actual coal than that in the design.Besides,the burner design defect led to the formation of the strong reducing atmosphere and a large amount of coal powder caused by the periodic large capacity test was accumulated in the water wall near the water wall fins.Therefore,some solutions were put forward,like adjusting the fineness of the pulverized coal,reconstructing the local modification of burner as well as the optimizing and adjusting of combustion.