常减压蒸馏装置水冷却器腐蚀原因分析与对策

Analysis of Causes of Corrosion in Water Cooler of Atmospheric-vacuum Distillation Unit and Countermeasures

随着国内加工原油品种日趋增多,原油变重、酸值增加,腐蚀问题加剧,与此同时水冷设备的设计选材等问题却一直被人们所忽视,导致该类水冷却器频繁泄漏或堵塞,给装置的平稳安全生产带来隐忧。针对常减压蒸馏装置水冷却器的堵塞和腐蚀泄漏问题,一方面结合腐蚀产物的化学性质来推断腐蚀机理,提出微观的氧浓差电池是造成水冷却器泄漏的主要原因;另一方面从设备的使用全过程入手,找出泄漏原因,结合自身经验提出水冷却器使用过程中应避免的问题,对水冷却器腐蚀问题提出合理建议。

Water cooler is one of common equipment in petroleum refineries,whose stable operation has a direct impact on process parameters and energy consumption of the unit.With increased varieties of crude oil being processed in China in recent years and crude oil is becoming increasingly heavier and acidic,great attention has been paid on the corrosion protection and materials of many heat exchange equipment have been upgraded.Whereas,the material selection for some non-critical cooler equipment has been ignored,which leads to frequent leaking or plugging of water coolers,imposing safety hazard on unit operation.To solve these problems,The chemical properties of corrosion products are analyzed to work out the corrosion mechanisms.It is found that the macro cell corrosion is the main cause of leaking of water cooler.In addition,the leaking causes are found out through comprehensive analysis of the operation process,and appropriate measures to control the corrosion of water coolers are recommended.