模拟塔里木油田环境中低Cr钢的H2S／CO2腐蚀行为

H_2S/CO_2 Corrosion Behavior of Low-Cr Steel in Simulated Tarim Oilfield Environments

通过高温高压腐蚀试验,运用SEM、XRD、EDS等分析技术,研究了普通P110与3Cr110钢在模拟塔里木油田现场环境中的CO2/H2S腐蚀特征。结果表明:在模拟CO2腐蚀环境中,这两种材料的腐蚀产物为FeCO3,3Cr110表现出良好的抗CO2均匀腐蚀及局部腐蚀能力,其平均腐蚀速率显著小于普通P110;模拟CO2/H2S腐蚀条件下,两种材料的均匀腐蚀速率远小于单独CO2腐蚀环境下的均匀腐蚀速率,表面腐蚀产物为FeS,H2S腐蚀占主导作用;Cr元素在低Cr钢腐蚀产物膜中的富集,其腐蚀产物Cr(OH)3改善了腐蚀产物膜的稳定性,显著提高了低Cr钢的抗均匀腐蚀及局部腐蚀能力。

The CO2/H2S corrosion behavior of two carbon steels, common Pl11 and low-Cr 3Cr110 in the simulated environment simulating Tarim Oilfield, was studied hy means of high temperature and high pressure corrosion tests, SEM, XRD and EDS, The results show that the corrosion products of 3Cr110 and P110 were identified as FeCO3 in CO2 corrosion environment, and the uniform corrosion rate of 3Cr110 was much less than that of common P110. In the simulated CO2/H2S environment, the corrosion product was FeS, and H2S corrosion predominated in the corrosion course. The uniform corrosion rates of the two materials were much less than those in CO2 environment. The enrichment of Cr in the corrosion scale on the low Cr steel improved the protection of corrosion scale, which enhanced the resistance of 3Cr110 to uniform and local corrosion.