DZG型锅筒底部特殊腐蚀失效事故的原因分析

Analysis on the Reasons of Special Corrosion Failure on the Bottom of "DZG"Boiler

本文对锅筒底部大面积腐蚀产生原因进行分析,确定为加入酸性"锅炉专用高效力除垢剂"后,使锅水总碱度和pH值严重偏小,锅内金属表面保护膜被破坏,引发锅筒底部高温区域产生大面积点坑状腐蚀的失效事故。锅炉在运行期间锅内加酸性除垢剂处理方法应引起锅炉监督管理机构和检验部门的关注。

The paper after analyzing the reasons of large area corrosion on the bottom of the boiler, we have ascertained that total alkalinity and PH value of the boiler water had been immensely diminished after the addition of acid scale remover, a special efficient scale remover for the boiler, and it has led the deterioration of metal protective film on the surface of the boiler, then the high temperature area on the bottom of the boiler has been massively corroded, and failure accidents happened. It is suggested that supervisory authorities and inspection department of the boiler should pay carefully attention to dealing with the acid scale remover during the operation of the boiler.