环境因素对N80钢在模拟油田采出液中腐蚀行为的影响

Influence of Environmental Factors on Corrosion Behavior of N80 Steel in Simulated Oilfield Produced Fluids

为研究不同环境因素影响下N80油管钢的腐蚀行为,采用极化曲线、交流阻抗、扫描电镜等方法研究了H^(+)、S^(2-)和Cl^(-)对N80钢在饱和CO_(2)模拟油田采出液中的腐蚀行为。结果表明:3种侵蚀性离子对N80钢腐蚀行为的影响由大到小为H^(+)、S^(2-)、Cl^(-)。随着3种侵蚀性离子浓度增加,N80钢腐蚀速率均增加。在低浓度Cl^(-)环境中,N80钢的腐蚀以阶梯状腐蚀和局部腐蚀为主,在高浓度Cl^(-)环境中,主要以点蚀为主;H^(+)会造成N80钢严重的局部腐蚀和均匀腐蚀,S^(2-)对N80钢的腐蚀失效以局部腐蚀为主。

The corrosion behavior of N80 steel under different environmental factors was explored.Polarization Curve,AC impedance spectroscopy test,SEM and other methods were used to study the effects of H^(+),S^(2-)and Cl^(-)ions on the corrosion behavior of N80 steel in saturated CO_(2)simulated oilfield production fluid.The results show that the influence of the three aggressive ions on the corrosion behavior of N80 steel is H^(+),S^(2-),Cl^(-).The corrosion rate of N80 steel increases with the concentration of three kinds of aggressive ions.In the environment of low concentration of Cl^(-),the corrosion morphology of N80 steel is mainly mesa corrosion and local corrosion,and in the environment of high concentration Cl^(-),it is mainly pitting corrosion.H^(+)can cause serious local corrosion and uniform corrosion of N80 steel,and the corrosion failure of N80 steel caused by S^(2-)is mainly local corrosion.