连续重整装置脱戊烷塔设备腐蚀原因分析及对策

Corrosion cause analysis and countermeasures on depentanizer of continuous reforming unit

关键词:  连续重整  脱戊烷塔  结盐  氯化铵

Key words:  continuous reforming  depentanizer  salt deposition  ammonium chloride

摘要:

针对某石化公司连续重整装置脱戊烷塔系统出现的设备腐蚀问题,通过对腐蚀部位进行宏观检查、涡流检测、腐蚀物分析等手段,并查阅相关参考文献,分析引发关键部位腐蚀的原因和机理,认为铵盐沉积是造成脱戊烷塔空冷器腐蚀泄漏的主要原因,并提出以下措施,以缓解装置脱戊烷塔系统的腐蚀:①加强原料中氮含量的控制；②脱戊烷塔进行塔顶水洗；③加注缓蚀剂；④更换高效的脱氯剂；⑤易腐蚀部位材质升级；⑥加强在线腐蚀监测方法。 

Abstract:

Aiming at the equipment corrosion problems of the depentanizer system of continuous reforming unit in a petrochemical company, through adopting the methods including macro inspection, eddy current testing, and corrosive analysis of the corrosion location, consulting relevant references, and analyzing the corrosion causes and corrosion mechanism of the key parts, it concluded that ammonium salt deposition was the main cause of depentanizer air cooler corrosion and leakage. Effective measures were put forward as follows:(1) Control the nitrogen content in the raw material； (2) make water washing on depentanizer overhead; (3) fill corrosion inhibitor; (4) replace efficient dechlorination agent; (5) update the material of easy corrosive parts; (6) strengthen the on-line corrosion detection method.