表面技术2025,Vol.54Issue(18):37-45,76,10.DOI:10.16490/j.cnki.issn.1001-3660.2025.18.004
不同材质油套管钢在CO2/H2S共存环境下的腐蚀行为及机理研究
Corrosion Behavior and Mechanism of Oil Casing Steel of Different Materials in CO2/H2S Coexistence Environment
摘要
Abstract
Pipe corrosion failure is a key factor affecting the safety of gas storage facilities.The work aims to explore the corrosion behavior and mechanism of five types of oil casing pipes,namely 80S,80S-3Cr,80S-5Cr,90S,and 90S-3Cr,based on the corrosion laws in the coexistent CO2/H2S environment of gas storage facilities,so as to optimize the oil casing steels resistant to corrosion by carbon dioxide and hydrogen sulfide. The steels of the five types of oil casing pipes were respectively cut into three rectangular specimens with dimensions of 30.0 mm×15.0 mm×2.8 mm.These specimens were polished smoothly with water-sandpaper and then cleaned and dried.A multi-phase flow dynamic circulation high-temperature and high-pressure reactor independently developed by the research group was used to simulate the working environment with coexistent CO2 and H2S in the gas storage facility.The prepared specimens were fixed inside the reactor body.The prepared simulated formation water solution was added into the reactor.All valves were closed,and N2 was introduced for 2-4 hours to remove oxygen.Then,CO2 was introduced to expel the nitrogen in the reactor.During the experiment,the temperature was maintained at 80 ℃,and the total pressure in the reactor was controlled at 38 MPa.The rotational speed of the electric motor was set according to a flow velocity of 2 m/s on the surface of the pipe material.The stirring device was started,0.038 MPa of H2S and 0.327 MPa of CO2 were introduced,and the timing was started.The experimental cycle was 336 hours.Subsequently,an EVO MA15 scanning electron microscope was employed to observe the micro-morphology of the specimen surfaces before and after the removal of corrosion products.The chemical components of the corrosion products were analyzed with the built-in Oxford energy-dispersive spectrometer.An X'Per 3 MRD X-ray diffractometer was used to analyze the phase structure and phase composition of the surface corrosion products.A white-light interferometer was used to analyze the three-dimensional morphology of the specimen surfaces after the removal of corrosion products and measure the depth of the corrosion pits. The 80S-5Cr had the minimum uniform corrosion rate of 0.049 8 mm/a.According to the corrosion grade standard,the uniform corrosion rates of the five types of pipes were all low,and they all suffered from moderate corrosion.In terms of pitting corrosion,the 90S-3Cr had the minimum pitting corrosion rate of 0.177 1 mm/a,and its corrosion pit depth was the shallowest,at 6.792 5 μm.The 90S-3Cr was moderately corroded,while 80S-5Cr,80S-3Cr,and 80S were severely corroded,and 90S was extremely severely corroded.The 80S-5Cr had the most excellent comprehensive performance.The chromium deposition on the surface of the Cr-containing steel formed a surface layer,which reduced the corrosion rate of the oil casing pipes.Moreover,as the Cr content increased,the corrosion resistance of the pipes gradually improved.This research provides a theoretical basis for the selection of oil casing pipes in the coexistent CO2/H2S environment in the underground of gas storage facilities.关键词
油套管/CO2/H2S/高温高压釜/腐蚀行为Key words
oil casings/CO2/H2S/high-temperature and high-pressure vessel/corrosion behavior分类
矿业与冶金引用本文复制引用
刘婉颖,张宁好,张智,丁思艺,任传谱,林泽洋,苟德成,李磊..不同材质油套管钢在CO2/H2S共存环境下的腐蚀行为及机理研究[J].表面技术,2025,54(18):37-45,76,10.基金项目
国家自然科学基金联合基金项目(U22A20164) (U22A20164)
国家自然科学基金(52074234) (52074234)
2024年四川省大学生创新训练计划项目(S202410615308) (S202410615308)
西南石油大学第23期课外开放重点实验项目(2023KSZ05049)The National Natural Science Foundation of China Joint Fund Project(U22A20164) (2023KSZ05049)
The National Natural Science Foundation of China(52074234) (52074234)
2024 Provincial College Student Innovation and Entrepreneurship Training Program Project:(S202410615308) (S202410615308)
The 23nd Extracurricular Open Key Experimental Project of Southwest Petroleum University(2023KSZ05049) (2023KSZ05049)