炼油厂重催装置换热器管束的泄漏原因

Leakage Reason of Tubes within Heat Exchanger of Residue Fluid Catalytic Cracking Unit in an Oil Refinery

某炼油厂重催装置E203换热器在运行过程中发生了管束泄漏,采用光学显微镜、扫描电镜、以及能谱分析等方法对失效原因进行了分析。结果表明:换热管内表面发生了严重的点蚀,腐蚀产物主要有Fe(OH)3、FeS和FeCl2;换热管内表面腐蚀产物中含有腐蚀性离子(Cl-和S2-),这是导致管束腐蚀失效的主要原因。

Leaking of tubes within heat exchanger of residue fluid catalytic cracking unit in an oil refinery occurred during running. The failure reasons were analyzed by means of optical microscopy, scanning electron microscopy and energy disperse spectroscopy. The results show that serious pitting occurred in the inner surfaee of the tube, and the corrosion products mainly consisted of Fe（OH）3, FeS and FeC12, corrosive ions such as CI- and S2- in the heat exchange tubes were the main reason for the corrosion and failure of tubes.