湿气温度对3Cr管线钢CO_2腐蚀行为的影响

Effect of Wet Gas Temperature on CO_2 Corrosion Behavior of 3Cr Pipeline Steel in Wet Gas Environment

利用高温高压冷凝反应釜模拟深海湿气管道的现场环境,研究了湿气温度对3Cr管线钢湿气CO2腐蚀行为的影响;运用扫描电镜(SEM)和能谱(EDS)等分析技术对试样表面腐蚀产物的形貌和成分进行了分析。结果表明,在相同管壁温度(10℃)下,湿气温度在30～90℃内范围变化时,3Cr管线钢的平均腐蚀速率随湿气温度的升高而增大,且都没有发生局部腐蚀。在这些湿气温度条件下,3Cr管线钢的腐蚀产物膜是两层结构,外层膜的主要成分为FeCO3,内层为非晶态的富Cr膜。

The effect of wet gas temperature on CO2 corrosion behavior of 3Cr pipeline steel in wet gas environment was investigated in high temperature and high pressure condensation autoclave by simulating the environment of wet gas pipelines in deep sea. The corrosion product was analyzed by SEM and EDS. The results showed that at the same temperature of the pipe wall（10℃）, the uniform corrosion rate of 3Cr steel increased with increasing the temperature of wet gas from 30℃ to 90℃, no localized corrosion was discovered at all temperatures. The corrosion scale on 3Cr steel had two-layer structure, and the outer layer was mainly composed of FeCO3. Cr element was enriched in the inner layer, which was in amorphous state.