水平井连续油管拖动转向酸化技术在艾哈代布油田的应用

艾哈代布油田主要采用长井段水平井线性井网开发,由于水平井段长、地层非均质性强,均匀布酸难度很大,为此,提出长井段水平井连续油管拖动酸化工艺及其辅助均匀布酸方法。结合储层特征,确定采用连续油管水平井段变速回抽酸化或定点酸化实现酸液的锥形注入形态,并使用转向酸液体系协助分段均匀布酸、水力喷射突破污染带等辅助布酸方法。现场应用结果表明,酸化后单井产量是酸化前的1.4倍,累计增产原油88.9×104 t,为油田建产提供了工程技术保障。

Application of coiled tubing withdrawing acidizing with diverting acid system in Ahdeb oil field,Iraq

Ahdeb Oilfield is the first oilfield reconstructed after the Iraqi War and mainly developed by long-lateral horizontal wells in linear well pattern. The wells, with a horizontal section of 800-1 000 m, face strong heterogeneity, and uneven acid distribution etc. in the process of acidizing. In view of these problems, the following measures were taken to assist effective acid distribution: CT was withdrawn continuously from high to low velocity along the whole horizontal section. Diverting acid system was used to help equalize acid distribution. The jetting nozzle was adopted to remove deep damage caused by the drilling fluid and completion fluid and improve acid penetration in relatively low permeability section. In the past 3 years, over 90 horizontal wells were stimulated with viscoelastic diversion acidizing, oil production of individual wells has increased by more than 1.4 times after acidizing, and cumulative oil production increment reaches 88.9×104 ton.