普通稠油开发水驱油转N₂驱油室内实验研究

Laboratory study on N₂ flooding after waterflooding for ordinary heavy oil development

章星¹ 杨胜来¹ 章玲² 李芳芳¹ 陈浩¹ 聂向荣¹ 丁景臣¹

中国石油大学（北京）石油工程教育部重点实验室，北京 102249 中国石油新疆油田公司风城油田作业区，新疆 克拉玛依 834011

MOE Key Laboratory of Petroleum Engineering, China University of Petroleum, Beijing 102249, China Fengcheng Oilfield Operation Zone, Xinjiang Oilfield Company, PetroChina, Karamay 834011, China

三塘湖油田在稠油开发过程中，具有流体渗流阻力大、油井产量低等特点。研究表明，水驱油转N₂驱油效率远远大于水驱油和N₂驱油效率，现场应制定合理的开采方式和工作制度。N₂突破时会出现采出程度大幅度增加，并对最终采收率有明显影响，矿场上应防止气体过早突破，提高N₂在地层中的波及面积和驱油效率。考虑到压力梯度的影响，初期水驱油应控制注入水流量及其注入体积，防止压漏地层或过早形成水窜，以提高油田产量。

Santanghu Oilfield is characterized by large fluid percolation resistance and low oil production in the process of heavy oil development. Laboratory study shows that the displacement efficiency of N₂ flooding after waterflooding is much higher than that of waterflooding and N₂ flooding. Rational development mode and working system should be worked out in field. A substantial increase of recovery degree will appear when N₂ breakthrough occurs, which will have an obvious influence on final recovery efficiency. Premature breakthrough of gas should be prevented in field in order to improve the sweep area of N₂ in formation and displacement efficiency. Considered the effect of pressure gradient, injected water flow and injected volume should be controlled in the process of initial waterflooding to prevent the formation breakdown or premature formation of channeling, which improves the oil production of this oilfield.

10.6056/dkyqt2012z1016