摘要
国内某600MW超临界机组由于实施节水减排,导致凝汽器不锈钢管发生了结垢和腐蚀现象。从循环水运行水质情况、不锈钢换热管在循环水中电化学腐蚀行为和材料性能等方面进行了研究分析。结果表明:循环水水质恶化导致凝汽器换热管结垢,垢下闭塞区氯离子发生富集,形成酸性环境诱发点蚀,同时垢下湿热环境中厌氧型细菌繁殖以及缓蚀性离子SO42-缺失等因素,促进了点蚀的发展,最终导致凝汽器换热管腐蚀穿孔发生泄漏。
Due to the water saving and emission reduction, the condenser stainless steel pipe of a domestic 600 MW supercritical unit scaled and corroded. The electrochemical corrosion behavior of stainless steel tube for the heat exchange, and the properties of materials were investigated. The results show that the quality deterioration of circulating water caused the scale formation in the heat exchange tube of condenser and chloride ion gathered under scale occlusion area, which induced pitting in an acidic environment. At the same time, anaerobic bacteria breeded in the hot and humid environment under the scale, and inhibitive sulfuric acid root ion was missing, which promoted the development of pitting and eventually led to corrosion perforation leakage in the heat exchange tube of condenser.
出处
《腐蚀与防护》
CAS
北大核心
2018年第1期55-58,62,共5页
Corrosion & Protection
关键词
节水减排
凝汽器
结垢
腐蚀
water saving and emission reduction
condenser
scaling
corrosion
