某油田地面注水管线腐蚀失效分析

Analysis on Corrosion Failure of Ground Water Injection Pipeline in an Oil Field

某油田注水管线近期发生多起腐蚀穿孔失效。运用高温高压反应釜对溶解氧腐蚀风险进行测试分析;运用OLI模拟软件对注入水的结垢腐蚀风险进行评估;同时借助细菌培养、扫描电子显微镜(SEM)、X射线衍射(XRD)等技术对注水管线的腐蚀产物进行分析。结果表明:溶解氧不是导致管线快速穿孔的关键因素;根据OLI模拟结果可知注入水的FeS和CaCO_3结垢风险较高;溶解氧腐蚀、垢下腐蚀与细菌腐蚀的协同作用导致油田注水管线发生快速的局部腐蚀腐蚀。

A number of corrosion leakage failures occurred recently in an oilfield water injection pipeline. In this paper,the risk of dissolved oxygen corrosion was analyzed with high-temperature and high-pressure autoclave,and the risk of fouling corrosion of the injected water was assessed with OLI simulation software,and meantime,the corrosion products of the failure water injection pipeline were studied by bacterial breeding,scanning electron microscopy( SEM) and X-ray diffractometer( XRD). Results showed that the dissolved oxygen was not a key factor in rapid leakage of pipelines;according to the simulation result of the OLI,Fe S and Ca CO3 in water injection pipeline led to the high fouling risk. Besides,the synergistic effects of dissolved oxygen corrosion,fouling corrosion,and bacterial corrosion resulted into the rapid localized corrosion of water injection pipeline in oilfield.