温度和压力对密相CO_(2)输送管线用X65钢腐蚀行为的影响  

Effect of Temperature and Pressure on the Corrosion Behavior of X65 Pipeline Steel Used for Transporting Dense Phase CO_(2)Fluids

作　　者：衣华磊 程璐瑶 胡丽华 李大朋 杨维健 孙冲 孙建波 YI Hualei;CHENG Luyao;HU Lihua;LI Dapeng;YANG Weijian;SUN Chong;SUN jianbo(State Key Laboratory of Offshore Oil and Gas Exploitation,Beijing 100028,China;CNOOC Research Institute Co.,Ltd.,Bejing 100028,China;School of Materials Science and Engineering,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]海洋油气高效开发全国重点实验室,北京100028 [2]中海油研究总院有限责任公司,北京100028 [3]中国石油大学(华东)材料科学与工程学院,青岛266580

出　　处：《腐蚀与防护》2024年第10期68-76,共9页Corrosion & Protection

基　　金：中海油“十四五”重大科研项目(KJGG-2022-12-CCUS-0103);中央高校基本科研业务费专项资金(20CX06075A)。

摘　　要：通过腐蚀模拟试验、表面分析技术和水化学模拟计算等手段,研究了在低含水及含O_(2)、H_(2)S、SO_(2)和NO_(2)杂质的密相CO_(2)腐蚀环境中X65管线钢的腐蚀行为,对比分析了温度和压力对X65钢腐蚀速率的影响及其原因。结果表明:温度和压力变化对X65钢的腐蚀速率影响显著,但不改变X65钢的腐蚀机理,X65钢表面形成了以FeOOH和FeSO_(4)为主的腐蚀产物膜。在恒压密相CO_(2)环境中,温度升高可以降低X65钢的腐蚀速率;而在恒温50℃密相CO_(2)环境中,随压力升高腐蚀速率先降低后显著增加;在试验温度和压力范围内,X65钢在10 MPa和50℃的密相CO_(2)环境中的腐蚀速率最低。温度和压力变化引起的X65钢腐蚀速率差异的原因与其造成的液相形成量及液相中腐蚀性物质含量的改变密切相关。The corrosion behavior of X65 pipeline steel in a dense phase CO_(2)corrosion environment with low water content and impurities such as O_(2),H_(2)S,SO_(2),and NO_(2)was studied through corrosion simulation experiments,surface analysis techniques,and hydrochemical simulation calculations.The influence of temperature and pressure on the corrosion rate of X65 steel and reasons were compared and analyzed.The results show that the changes of temperature and pressure had a significant impact on the corrosion rate of X65 steel,but did not change the corrosion mechanism of X65 steel.A corrosion product film mainly composed of FeOOH and FeSO4 formed on the surface of X65 steel.In a dense CO_(2)environment with a constant pressure of 10 MPa,an increase in temperature could reduce the corrosion rate of X65 steel.In a dense CO_(2)environment at a constant temperature of 50℃,the corrosion rate first decreased and then significantly increased with increasing pressure.Within the experimental temperature and pressure range,X65 steel had the lowest corrosion rate in a dense CO_(2)environment at 10 MPa and 50℃.The reason for the difference in corrosion rate of X65 steel caused by temperature and pressure changes was closely related to the changes in the amount of liquid phase formation and the content of corrosive substances in the liquid phase.

关 键 词：X65管线钢 密相CO_(2) 温度 压力 腐蚀 

分 类 号：TG178[金属学及工艺—金属表面处理]