CO_(2)驱注气管柱腐蚀失效分析  

Corrosion Failure Analysis of CO_(2) Flooding Injection String

作　　者：江绍静 肖沛瑶 王珂 汤瑞佳 刘春燕 刘晶静[3] JIANG Shao-jing;XIAO Pei-yao;WANG Ke;TANG Rui-jia;LIU Chun-yan;LIU Jing-jing(Research Institute of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Xi’an 710065,China;Natural Gas Research Institute Branch of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.,Xi’an 710065,China;Wuqi Oil Production Plant of Yanchang Oilfield Co.,Ltd.,Yan an 717600,China)

机构地区：[1]陕西延长石油(集团)有限责任公司研究院,西安710065 [2]陕西延长石油(集团)有限责任公司天然气研究院分公司,西安710065 [3]延长油田股份有限公司吴起采油厂,延安717600

出　　处：《科学技术与工程》2025年第6期2301-2310,共10页Science Technology and Engineering

基　　金：陕西省秦创原碳中和背景下油藏CO_(2)地质封存关键技术“科学家+工程师”项目(2022KXJ-050);延长石油集团“揭榜挂帅”项目(ycsy2021jbgs-A-04)。

摘　　要：CO_(2)驱油是CO_(2)捕集、利用与封存(carbon capture,utilization and storage,CCUS)技术中CO_(2)地质利用环节的重要组成部分,延长油田开展CO_(2)驱油与封存项目取得了良好的增油封碳效果,但实际CO_(2)驱注入环境下的管柱腐蚀失效原因尚不明晰。利用扫描电镜(scanning electron microscopy,SEM)、3D共聚焦显微镜、能谱分析(energy dispersive spectrometer,EDS)、X射线衍射(X-ray diffraction spectroscopy,XRD)等实验手段对取自吴起某CO_(2)驱油与封存示范区注气管柱的腐蚀形貌进行表征,并对管柱腐蚀产物进行分析,以期明确研究区CO_(2)驱注气管柱腐蚀失效原因。结果表明:以CO_(2)腐蚀为主导的局部腐蚀造成注气管柱的腐蚀失效,腐蚀产物包括FeCO_(3)、Fe的高价氧化物及少量FeS。分析认为,低温CO_(2)的连续注入不会引起管柱腐蚀,但CO_(2)停注期间井筒温度回升、地层水上返使得注气管柱具备了发生CO_(2)/H_(2)S腐蚀的条件,且注气井转注水进一步加剧了管柱腐蚀。建议在CO_(2)停注以及转注水期间加强对注气管柱的杀菌与防腐措施。CO_(2) flooding is an important part of the CO_(2) geological utilization process in CCUS(carbon capture,utilization and storage).The CO_(2) flooding and storage project carried out in the Yanchang Oilfield has achieved good results in increasing production and storing CO_(2).But the reasons of pipe string corrosion failure are still unclear during CO_(2) injection.SEM(scanning electron microscopy),3D confocal microscopy,EDS(energy dispersive spectrometer)and XRD(X-ray diffraction spectroscopy)were used to characterize the corrosion morphology of the gas injection pipe string in the CO_(2) flooding and storage demonstration area of Wuqi Oilfield.The pipe string corrosion products are analyzed to clarify the reasons for pipe string failure caused by CO_(2) corrosion.The results show that local corrosion dominated by CO_(2) corrosion causes corrosion failure of the pipe string.Corrosion products include FeCO_(3),high-priced oxides of Fe and a small amount of FeS.Continuous injection of low-temperature CO_(2) cannot cause corrosion.However,the increase in wellbore temperature and the return of formation water caused by stopping CO_(2) injection can create conditions for CO_(2)/H_(2) S corrosion in the pipe string.In addition,pipe string corrosion is accelerated when gas injection wells are converted into water injection wells.It is recommended to strengthen the sterilization and anti-corrosion measures for the pipe string during the period of stopping CO_(2) injection and switching to water injection.

关 键 词：CO_(2)驱油 CO_(2)/H_(2)S电化学腐蚀 管柱腐蚀 腐蚀失效 防腐措施 

分 类 号：TG172.2[金属学及工艺—金属表面处理]