油井井下连续滴加缓蚀剂技术

Research and Application of Titration Injection of Corrosion Inhibitor in Oil Wells

针对中国石油天然气股份公司长庆油田分公司长期以来油水井内腐蚀严重问题,并根据陇东老区部分油水井内以CO_2和硫酸盐还原茵腐蚀、靖东以H_2S腐蚀为主的特点,评价、筛选出了抗CO_2和H_2S腐蚀的缓蚀剂。采用的缓蚀剂井下滴加装置能够实现药液的长期、稳定连续加药,可稳定控制产出液介质中的缓蚀剂浓度,实现最佳加药效果,加药周期在8个月以上。通过陇东和靖东各5口井的现场试验,缓蚀率最高达到96%,挂片表面光亮无点蚀,有效抑制了油井内腐蚀。

The oil wells in Petronhina Changqing Oil Field Compang suffered from severe corrosion. Based upon the characteristics of CO2 corrosion and SRB corrosion in oil wells in Longdong Area and H2 S corrosion in wells in Jingdong Area, corrosion inhibitors resisting CO2 and H2 S corrosion were evaluated and screened. The inhibitor can be injected inside the wells by titration devices for long - term continuous injection and control of corrosion inhibitor concentration in production liquid so as to achieve good inhibition results. The injection cycle is over 8 months. The field tests in the 5 wells in Longdong Area and 5 wells in Jingdong Area show that the corrosion inhibition rate is as high as 96%, there is no pitting corrosion on the surface of test coupons, which indicates that the corrosion has been effectively controlled.