CO2吞吐管柱腐蚀分析及防治研究

针对CO₂吞吐井杆管腐蚀严重的问题,对吞吐油井管柱进行了腐蚀产物分析。通过微观形貌分析、能谱分析、金相分析以及X射线衍射分析等手段,确定了吞吐区块油井腐蚀类型为CO₂腐蚀。通过腐蚀规律研究,提出了以液体缓蚀剂、固体缓蚀剂等化学防腐保护技术为主,加深尾管保护技术、牺牲阳极保护技术、油管涂层保护技术为辅的综合腐蚀防治技术思路,并通过实验确定了合理的加药量与加药方法。综合腐蚀防治技术在69口井中开展现场试验,对吞吐井杆管取得了较好的保护效果,油井免修期由260天延长到400天,验证了综合腐蚀防治技术的有效性。

Corrosion analysis and protection of pipe strings in CO2 huff and puff well

Aiming at the serious problem of tubing corrosion in huff and puff well, the corrosion products of carbon dioxide stimulation wells were analyzed. The corrosion type of huff and puff oil well are determined as carbon dioxide corrosion, by using methods of microscopic morphology analysis, energy spectrum analysis, metallographic analysis and X-ray diffraction analysis. Basing on the study of corrosion law, a comprehensive corrosion prevention and control technology thought was put forward, which includes liquid corrosion inhibitor, solid corrosion inhibitor and other chemical corrosion protection technology as primary, deepening liner protection technology, sacrificial anode protection technology and tubing coating protection technology as auxiliary. The reasonable dosage concentration and dosage method of corrosion inhibitors were determined through experiments. Field tests were carried out in 69 wells, and the oil well lifetime has been extended from 260 days to 400 days, which verifies the effectiveness of the comprehensive corrosion prevention and control technology.