摘要
针对天然气管道的内腐蚀问题,利用高温高压反应釜模拟了低pH值及H_(2)S/CO_(2)共存环境,结合SEM、EDS以及XRD技术探讨了H_(2)S分压、实验温度以及外加应力对X80管线钢的腐蚀速率与腐蚀机理的影响。结果表明,纯CO_(2)腐蚀远较H_(2)S/CO_(2)共存时严重;含H_(2)S条件下,腐蚀产物膜中非晶态Cr(OH)_(3)能提升FeS膜的稳定性,起到表面保护和降低腐蚀速率作用。H_(2)S/CO_(2)共存时,X80管材发生H_(2)S腐蚀反应为主的均匀腐蚀,腐蚀速率随H_(2)S分压增大而升高;腐蚀速率随着环境温度的增加先增后减,在设定的实验条件下,最高的腐蚀速率发生在100℃附近;外加应力对腐蚀速率影响显著,腐蚀速率随应力增加快速升高。
Internal corrosion of pipeline is an important factor affecting the safety of natural gas transmission.A high temperature-pressure reactor is used to simulate the low pH H_(2)S/CO_(2)coexistence environment,and the effects of H_(2)S partial pressure,experimental temperature and applied stress on the corrosion rate and corrosion mechanism of API X80 steel are discussed,combined with SEM,EDS and XRD techniques.The results show that the corrosion of the samples under pure CO_(2)condition is much serious than that under H_(2)S/CO_(2)coexistence.The corrosion stability of amorphous film under H_(2)S-containing environment can be improved to by the formation of amorphous Cr(OH)_(3),therefore the surface protection is more obvious than that in pure CO_(2)condition.The X80 steel is subject to uniform corrosion dominated by H_(2)S corrosion,and the corrosion rate increases with the increase of H_(2)S partial pressure.The corrosion rate firstly increases and then decreases with the increase of ambient temperature,and the highest corrosion rate occurs when the temperature reaches near 100℃ under the present experimental conditions.The external stress has a significant effect on the corrosion rate,and the corrosion rate increases rapidly with the increase of stress.
作者
李玉坤
黄小光
周龙池
彭启凤
LI Yukun;HUANG Xiaoguang;ZHOU Longchi;PENG Qifeng(College of Pipeline and Civil Engineering,China University of Petroleum,Qingdao 266580,Shandong,China)
出处
《实验室研究与探索》
CAS
北大核心
2023年第1期43-48,58,共7页
Research and Exploration In Laboratory
基金
山东省自然科学基金项目(ZR2020ME092)。
关键词
天然气管线
X80钢
腐蚀速率
温度
应力
natural gas pipeline
X80 steel
corrosion rate
temperature
stress
