正交试验法研究X90管线钢在CO_2环境中的腐蚀行为

通过正交试验法研究了CO_2环境中各因素对X90管线钢腐蚀行为的影响。结果表明:各因素对X90管线钢在CO_2环境中腐蚀速率的影响按大小顺序是原油含水率、温度、CO_2分压、流速;X90管线钢腐蚀产物膜表面布满网状裂纹,呈鳞片状,产物膜结构疏松,对基体保护作用较弱,表面点蚀坑较多,点蚀严重,X90管线钢抗CO_2腐蚀性能较差;产物膜成分随腐蚀环境变化而不相同,所有产物中都含有FeCO_3和Fe,部分试样产物膜中还有腐蚀介质析出的碳酸盐。

Corrosion Behavior of X90 Pipeline Steel in CO2 Environment Evaluated by Orthogonal Test

The effects of different factors on corrosion behavior of X90 pipeline steel in CO2 environment were investigated by orthogonal test.The results show that the influence factors on corrosion rate of X90 pipeline steel in CO2 environment ranked from big to small were water content ratio of crude oil,temperature,CO2 partial pressure,flow velocity.The corrosion product film of X90 pipeline steel covered with net cracks on its surface was scaly.The structure of corrosion product film was loose,so it had weak protection for the matrix.There were a lot of pits on the surface,and the pitting corrosion of the steel was serious.The resistance to CO2 corrosion of X90 pipeline steel was comparatively poor.The corrosion products were different when the corrosion conditions changed,but all the corrosion products contained FeCO3 and Fe,and part of the corrosion products contained carbonate precipitated from corrosion medium.