利用高温高压反应釜模拟高含硫气田H2S/CO2共存环境, 分别在流动湿气和溶液介质中进行API-X60腐蚀实验, 探讨了高H2S分压对腐蚀行为的影响. X60管线钢的腐蚀速率在湿气介质中随H2S分压升高而增加, 在溶液介质中则先升高后降低, 腐蚀形态均由全面腐蚀趋于局部腐蚀, 腐蚀产物以硫铁化合物(FexSy)为主. H2S分压为2.0 MPa条件下, 溶液介质中形成的腐蚀产物中富S相比例明显增加, HS-和Cl-穿过膜层缺陷引发点蚀, 多孔且不连续的富S膜层进一步促进点蚀发展.
Wet gas and solution environments containing H2S/CO2 were simulated in a high temperature and high pressure autoclave. Corrosion behaviors of API-X60 pipeline steel were investigated with Scanning Electron Microscopy (SEM) and X-ray Diffraction methodology (XRD). Effects of high H2S partial pressure on corrosion rate and scale were discussed. The results show that corrosion rate increased with H2S partial pressure in wet gas but raised up first and then dropped down in the solution immersion environment. Pitting corrosion was observed at the situations with H2S partial pressure 2.0MPa. The corrosion process was controlled by H2S and mackinawite (Fe1＋XS) was the dominant composition in the corrosion products free of FeCO3. Pitting was occurred in the scale’s defect which was acidified by the HS- and Cl- ions migrating, and the development of the pitting was affected by the electrochemical property of the sulfur-rich phase and FeCl2 admixture. The crystal morphology and structure were more complicated in the scales formed in immersion environment, which were less integrated and bonded than that formed in wet gas. However, hydrogen blistering and hydrogen-induced cracking were more easily occurred for X60 in wet gas than that in immersion environment.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] | |
| [8] |
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