延长油田油井管柱腐蚀原因分析及防腐措施研究  

Cause analysis and anti-corrosion measures of oil well string corrosion in Yanchang Oilfield

作　　者：庞静 郭振华 李鑫[1] 于昕东 PANG Jing;GUO Zhen-hua;LI Xin;YU Xin-dong(Qilicun Oil Production Plant of Yanchang Oilfield Co.,Ltd.,Yan'an 717111,China)

机构地区：[1]延长油田股份有限公司七里村采油厂,陕西延安717111

出　　处：《化学工程师》2022年第8期81-84,共4页Chemical Engineer

基　　金：延长石油重大科技项目(ycsy2020xjs-c-05)。

摘　　要：为了找出延长油田油井管柱腐蚀的主要原因,室内采用挂片失重法实验对影响管柱腐蚀的主要因素进行了评价,主要包括采出液含水率、矿化度、pH值、CO_(2)含量、温度以及流速,并根据实验结果优选了适合延长油田油井管柱的高效缓蚀剂ND-F。实验结果表明,油井采出液的含水率越高、矿化度越高、CO_(2)含量越高、温度越高以及流速越大,其对油井管柱钢材的腐蚀速率就越大,而采出液的pH值越高,腐蚀速率则越小。当采出液的含水率为80%,矿化度为25000mg·L^(-1),pH值为6,CO_(2)分压为0.5MPa,实验温度为50℃,实验流速为0.5m·s^(-1)时,钢片的腐蚀速率可以达到0.557mm·a^(-1),腐蚀速率较大。咪唑啉类缓蚀剂ND-F对目标油田油井管柱钢材的防腐效果较好,当其加量为900mg·L^(-1)时,缓蚀效率就可以达到95%以上,能够显著降低油井管柱的腐蚀速率,延长其使用寿命,保障延长油田油井的安全高效生产。In order to find out the main causes of oil well pipe string corrosion in Yanchang Oilfield,the hanging weight loss method was used to evaluate the main factors affecting pipe string corrosion,mainly including produced fluid water content,salinity,pH value,CO_(2) content,temperature and flow rate.According to the experimental results,the high-efficiency corrosion inhibitor ND-F suitable for oil well pipe string in Yanchang Oilfield was optimized.The experimental results showed that the higher the water content,the higher the salinity,the higher the CO_(2) content,the higher the temperature and the greater the flow rate of the oil well produced fluid,the greater the corrosion rate of the oil well string steel,while the higher the pH value of the produced fluid,the smaller the corrosion rate.When the water content of the produced liquid is 80%,the salinity is 25000mg·L^(-1),the pH value is 6,the CO_(2) partial pressure is 0.5MPa,the experimental temperature is 50℃and the experimental flow rate is 0.5m·s^(-1),the corrosion rate of the steel sheet can reach 0.557mm·a^(-1),and the corrosion rate is large.Imidazoline corrosion inhibitor ND-F has good anti-corrosion effect on the steel of oil well string in the target oilfield.When its dosage is 900mg·L^(-1),the corrosion inhibition efficiency can reach more than 95%,which can significantly reduce the corrosion rate of oil well string,prolong its service life and ensure the safe and efficient production of oil wells in the oilfield.

关 键 词：延长油田 油井管柱 腐蚀原因 防腐措施 缓蚀剂 

分 类 号：TE341[石油与天然气工程—油气田开发工程]