炼化装置碱性介质环境设备失效机理及解决方案

Failure mechanism and solution of equipment under alkaline medium environment in refining and chemical plant

碱性介质是炼化装置中较为常见且危害较大的一类腐蚀性介质,已成为催化裂化、延迟焦化、加氢、废碱处理等诸多装置设备泄漏和开裂的重要诱因。列举了几种常见的碱性腐蚀介质对设备和管线的腐蚀形式,辅以现场实际腐蚀案例,深入剖析了其腐蚀机理、影响因素和失效危害。针对每种腐蚀形式重点介绍了材料选择方案,并从结构设计、设备制造、现场操作优化等角度提出了预防碱性环境腐蚀的措施,有助于减缓相关腐蚀,保障炼化装置的长周期稳定运行。

Alkaline medium was a kind of common and harmful corrosive medium in refining and chemical plants,which was an important inducement for leakage and cracking of many units such as catalytic cracking,delayed coking,hydrogenation,waste alkali treatment.Several common corrosion forms of alkaline mediums on equipment and pipelines were listed,and the corrosion mechanism,influencing factors and failure hazards were analyzed based on the actual corrosion cases on site.Material selection options were introduced for each form of corrosion;meanwhile,the measures to prevent corrosion in alkaline environment were put forward from the aspects of structural design,equipment manufacturing,and on-site operation optimization to slow down the corrosion and ensure long-term stable operation of refining unit.