蜡油加氢装置空冷器入口管泄漏原因分析及对策

某公司蜡油加氢装置脱H2S塔塔顶空冷器入口管出现了泄漏。通过泄漏部位管道取样和对样品管道进行的宏观检查、化学组成分析、金相组织观察等物理化学检验检测,初步判断泄漏为氯化铵盐腐蚀导致。结合工艺流程和铵盐结晶腐蚀机理分析,进一步确定管道保温层缺失、低负荷运行导致了氯化铵盐在空冷器入口管的结晶、沉积、垢下腐蚀,腐蚀的加剧引发了管道泄漏。基于分析结果,提出了针对性的调控工艺操作及增补管道保温结构措施。

Cause Analysis and Solution for Inlet Pipe Leakage of Air Cooler in Wax Oil Hydrogenation Unit

The leakage was found in the inlet pipe of the air cooler at the top of the hydrogen sulfide removal tower of a wax oil hydrogenation unit.According to the physical and chemical tests such as the sampling of the leaking pipeline and the macroscopic inspection,chemical composition analysis and metallographic structure observation,it was preliminarily determined that the leakage was caused by the corrosion of ammonium chloride.Combined with the analysis of process flow and ammonium salt crystallization corrosion mechanism,it was further determined that the loss of pipeline insulation layer and low load operation led to the crystallization,deposition and corrosion under scale of ammonium chloride in the inlet pipe of air cooler,and the aggravation of corrosion led to pipeline leakage.Based on the analysis results,the corresponding control process operation and the supplement of pipeline insulation structure measures were proposed.