摘要
CO_2辅助蒸汽驱是稠油开采的新型方式,但有关CO_2辅助蒸汽驱注气井中井下管柱CO_2腐蚀行为的研究较少。为此,利用高温高压釜模拟CO_2辅助蒸汽驱注气井筒工况,在CO_2分压为2MPa,240℃的条件下,对4种常用的油套管钢进行了失重腐蚀挂片试验,得到了模拟工况下油套管钢的腐蚀速率,利用SEM观察了4种材质的微观腐蚀形貌,并采用SEM和EDS对4种管材的腐蚀产物进行了表征。结果表明,在实验条件下,4种材质的均匀腐蚀速率均小于油田的腐蚀控制指标(0.076 mm/a);N80钢的腐蚀形态为均匀腐蚀,而3Cr、9Cr和13Cr钢的腐蚀形态为局部腐蚀;4种钢材的腐蚀速率均满足CO_2辅助蒸汽驱注气井筒腐蚀控制要求。
CO2-assisted steam flooding is a novel method for heavy oil production.However,studies on CO2 corrosion of downhole pipe in a high-temperature steam environment are relatively scarce.Therefore,in this study,the CO2 corrosion behavior of oilfield pipe casing steel in a high-temperature steam environment was investigated using four types of oilfield pipe casing steel.A high-temperature,high-pressure autoclave was used to simulate the operating conditions during CO2-assisted wellbore steam flooding.With a CO2 partial pressure of 2 MPa and an operating temperature of 240 C,a weight loss coupon corrosion test was performed on four types of oilfield pipe casing steel,and the corrosion rates of the pipeline materials under the simulated operating conditions were obtained.Scanning electron microscopy,energy dispersive x-ray spectrometry,and x-ray diffraction were used to determine the morphology and composition of the corrosion products.The results show that under the experimental conditions,the uniform corrosion rates of the four types of materials were lower than the allowable corrosion rate for oil fields(0.076 mm/a).The corrosion morphology of N80 steel was uniform corrosion,while that of 3Cr,9Cr,and 13CR steel were localized corrosion.The corrosion rates of all four steel materials met the corrosion control requirements for CO2-assisted wellbore steam flooding.
作者
石善志
董宝军
曾德智
于会永
陈禹欣
SHI Shanzhi;DONG Baojun;ZENG Dezhi;YU Huiyong;CHEN Yuxin(Research Institute of Engineering Technology,Xinjiang Oilfield Company,PetroChina,Karamay,Xinjiang 834000,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China)
出处
《西南石油大学学报（自然科学版）》
CAS
CSCD
北大核心
2018年第4期162-168,共7页
Journal of Southwest Petroleum University(Science & Technology Edition)
基金
国家自然科学基金(51774249
51374177)
国家科技重大专项(2016ZX05012-001)
关键词
CO2辅助蒸汽驱
CO2腐蚀
井下管柱
腐蚀速率
腐蚀形貌
CO2-assisted steam flooding
CO2 corrosion
downhole pipe
corrosion rate
corrosion morphology
