污油污水罐内壁强制电流阴极保护的应用

Application of Impressed Current Cathodic Protection for Oilfield Produced Water Tank

目前国内污油污水罐普遍采用牺牲阳极保护,但存在阳极消耗快,输出电流不可调,需定期开罐更换阳极等问题,这不仅增加了维护投资,而且延误了正常生产。为解决上述问题,采用强制电流进行阴极保护是最有效的方法之一。结合华北油田鄚一站的1000m^3污油污水罐,介绍了罐内壁采用强制电流进行阴极保护的方法,通过在罐内悬挂金属氧化物阳极和安装长效锌参比电极,不仅使阳极输出电流可调,延长了阴极保护系统的使用寿命,而且实现了可在罐外对罐内不同点的保护电位进行监测。工程实践证明,华北油田鄚一站1000m^3污油污水罐采用强制电流进行阴极保护,其防腐效果良好,目前已正常运行1年多了,各项参数均控制在合理的范围内。

Sacrificial anodes are widely used for oilfield produced water tanks, but there are some problems such as fast consumption of sacrificial anode, unadjustable current output and required regular replacement of the sacrifi- cial anode. Thus, not only the maintenance investment increases, but also the normal production is affected. Impressed current cathodic protection is the most effective method to solve the problems. This paper intro- duces the application effect of the impressed current cathodic protection in the 1 000 m3 oilfield produced wa- ter tank at Mao-1 station of Huabei Oilfield. Hanging anodes and installing long-term zinc reference electrodes in the tank not only enable current output to be adjustable and prolong service life of the cathodic protection system, but also realize to monitor protection potentials at different points inside the tank from outside of the tank. The effect of the cathodic protection system has normally worked for more than one year with perfect anticorrosion effect, all parameters has been within reasonable ranges.