X80管线钢在含硫原油中的顶部腐蚀行为

摘要

Corrosion coupon testing and scanning electron microscopy (SEM) were used to research the top-of-line corrosion (TLC) behavior of X80 pipeline steel in sour crude oil with different sulfur contents at different temperature differences.The results show that with the increase of concentration of S2-,X80 steel corrosion rate increased firstly and then decreased.When the temperature difference was in the range of 20-70 ℃,the corrosion rate exhibited a trend of increase followed by decrease.The corrosion rate was maximum at the temperature difference of 40 ℃.Uniform corrosion and a very dense and thin FeS2 layer were found at the top of the pipe.When the temperature difference was low and the condensation rate of steam was high,a thicker and more porous outer layer formed on its surface.%通过腐蚀挂片试验及扫描电子显微镜研究了X80管线钢在含硫原油中、不同硫含量和温差条件下管道顶部的腐蚀行为.研究表明:随着原油溶液中硫离子含量的增加,X80管线钢顶部腐蚀速率先增大后减小;温差为20～70℃时,随温差的增大,腐蚀速率先增大后减小,温差40℃时达到峰值;管道顶部发生了均匀腐蚀,产生致密的FeS2薄层,但在温差较小、水蒸气的冷凝速率较高的情况下,管道顶部表层会生成较厚且多孔的外层膜.