催化裂化装置腐蚀失效分析与实验室模拟实验研究  

FAILURE ANALYSIS OF CORROSION CRACKING AND SIMULATING TEST FOR FCCU

作　　者：陈华[1] 李明[1] 李晓刚[1,2] 杨锦文[3] 陈鸣皋[3] 

机构地区：[1]北京科技大学腐蚀与防护中心,北京市腐蚀,磨蚀与表面技术开放实验室,北京100083 [2]中国科学院金属研究所腐蚀与防护国家重点实验室,九江332004 [3]中国石油化工股份有限公司九江分公司

出　　处：《机械强度》2004年第6期691-695,共5页Journal of Mechanical Strength

基　　金：受973项目 (0 1 9990 0 650 );中国石油化工集团公司技术中心的支持。

摘　　要：通过对催化裂化再生器在NOx SOx H2 O环境下现场构件的无损检测、硬度测定、化学成分分析、介质分析、金相检验、断口分析及腐蚀产物分析等表明 ,催化裂化再生系统由于设备壁温长期处于烟气露点温度 ,在NOx SOx H2 O烟气结露形成的酸性腐蚀介质和残余应力的共同作用下 ,发生硝酸盐应力腐蚀开裂。实验室进行的现场模拟实验所得的结果与催化裂化再生器现场失效构件的实验结果具有共同的特征 ,进一步论证了现场装置的开裂是由硝酸盐应力腐蚀开裂引起的。力图对再生器设备在NOx SOx H2 O烟气体系中产生的应力腐蚀开裂进行预测 ,并为进一步研究有效的防护对策提供科学的依据。Some nondestructive detection methods, hardness measurement, analysis of chemical compositions, medium, fracture surface and corrosion products, optical microscopy were used to investigate the reason of the cracking in the recycled system of fluid catalytic and cracking unit (FCCU). The analysis results showed that the crack were stress corrosion cracking which are caused by nitrate, and were generated together with the acidic corrosive medium below dew point temperature in mixing fume NO x-SO x-H 2O environment. The result of simulating test in laboratory displayed the same characteristics as that of failured instruments in the equipment. It can be further proved that stress corrosion cracking caused by nitrate was the major reason of cracking for FCCU. Some suggestions are proposed to prevent the occurrences of stress corrosion cracking of FCCU.

关 键 词：应力腐蚀 催化裂化装置 露点 失效 

分 类 号：TG172.3[金属学及工艺—金属表面处理] TG115.5[金属学及工艺—金属学]