炼油厂重催装置分馏塔顶换热器管束的腐蚀失效分析  

Corrosion Failure Analysis of Heat Exchanger Tube Bundle in Oil Refinery Residue Fluid Catalytic Cracking Unit Fractionating Tower Top

作　　者：李辉辉[1] 胥聪敏[1] 杨东平[1] 

机构地区：[1]西安石油大学材料科学与工程学院材料加工工程重点实验室,西安710065

出　　处：《机械工程材料》2015年第5期102-106,共5页Materials For Mechanical Engineering

基　　金：陕西省教育厅专项科研计划项目(2013JK0895);陕西省重点学科专项资金资助项目

摘　　要：某炼油厂重催装置分馏塔顶换热器管束在使用18个月后发生了腐蚀失效,采用扫描电镜、能谱仪和X射线衍射仪等对失效原因进行了分析。结果表明:换热管外表面发生了严重的点蚀,最大腐蚀坑深度为0.98 mm,达到了管壁厚度的40.3%;换热管外表面的腐蚀产物主要有α-FeO(OH)、Fe2O3、Fe3O4、FeS和FeCl2;换热管外表面所处介质环境中的腐蚀性离子(Cl-和S2-)含量很高,这是导致换热器管束腐蚀失效的主要原因。Corrosion failure of heat exchanger tube bundle in oil refinery residue fluid catalytic cracking unit fractionation tower top occured after using for 18 months, the causes were analyzed by scanning electron microscopy, energy disperse spectroscopy and X-ray diffraction. The results show that the outer surface of the heat exchange tube exhibited serious pitting, the maximum depth of corrosion pits was 0. 98 ram, accounting for 40. 3% of the tube thickness. The corrosion products on the outer surface of the heat exchange tube were mainly α-FeO（OH）, Fe2O3, Fe3O4, FeS and FeCl2. The content of corrosive ions （Cl and S2- ） in the media around heat exchange tube outer surface was very high, this was the main reason leading to corrosion failure for heat exchanger tube bundle.

关 键 词：换热管 局部腐蚀 腐蚀产物 腐蚀失效 渗铝钢 

分 类 号：TG172.7[金属学及工艺—金属表面处理]