埋地油气管道腐蚀失效研究进展及思考

Research progress and thinking on corrosion failure of buried oil and gas pipelines

随着油气管道服役时间的延长,管道面临的腐蚀失效问题愈加严峻。阐述了中国埋地油气管道腐蚀现状,总结了埋地管道常见的腐蚀失效类型,讨论了油气管道酸腐蚀、微生物腐蚀、应力腐蚀开裂(SCC)及氢损伤的作用机理,分析了温度、腐蚀性阴离子、阴极保护电位、磁场和交流电等环境因素对管道腐蚀的影响。针对当前埋地油气管道腐蚀失效研究尚不充分,机理、规律尚未完全明确的现状进行讨论,以期为未来油气管道腐蚀失效的研究方向选择提供参考:在点蚀穿孔方面,未来应结合多相流模型和弱酸腐蚀机理建立弱酸作用下的腐蚀预测模型,以准确评估油气管道腐蚀程度,采用扫描振动电极技术等手段深入开展微观层面的腐蚀机理研究;在SCC方面,未来可将模拟计算方法与更高分辨率的显微原位观测技术相结合来解析管道应力腐蚀本质。

With the increase of service time, oil and gas pipelines have serious corrosion failure problems. Herein, the corrosion status of buried oil and gas pipelines in China was clarified, the common corrosion failure types of the buried pipelines were summarized, the mechanism of acid corrosion, microbial corrosion, stress corrosion cracking and hydrogen damage of oil and gas pipelines was discussed, and the effects of environmental factors such as temperature, corrosive anions, cathodic protection potential, magnetic field, and alternating current on pipeline corrosion were analyzed. In addition,discussion was performed for the present status of inadequate study on corrosion failure of buried oil and gas pipelines and the mechanism and laws that are not cleared completely, so as to provide reference for the selection of research direction of corrosion failure of buried oil and gas pipelines in the future. In terms of pitting corrosion perforation, a corrosion prediction model under the action of weak acid should be established based on the multi-phase flow model and weak acid corrosion mechanism to accurately evaluate the corrosion of oil and gas pipelines in the future, and the scanning vibration electrode technology and other means should be used to carry out in-depth research on the corrosion mechanism at the micro level: In terms of SCC, the simulation calculation method can be combined with higher resolution microscopic observation technology to analyze the nature of stress corrosion in pipelines in the future. The results of the study.