双河Ⅴ_上层系特高含水期提高采收率技术实践

PRACTICE OF EOR DURING THE ULTRA-HIGH WATER CUT PERIOD IN SHUANGHE Ⅴ FORMATION

双河油田Ⅴ上层系综合含水高达95.21%,已进入特高含水开发后期,层间层内非均质性严重,层间动用状况差异大,主力油层水淹严重。分析了Ⅴ上层系开发中所面临的主要问题:油水井井距大,井网不完善,注水利用率低,注水井吸水剖面不均匀。利用油水井测井测试资料和油藏数值模拟方法,明确了特高含水开发后期剩余油潜力分布。指出下步的调整方向是油层边角部位、断层附近的剩余油富集区和剩余储量高的部位。提出了井网完善调整、调剖封堵大孔道、三次采油等技术,应用于现场实际中,取得了明显的降水增油效果,提高了水驱采收率,形成了一套特高含水开发后期提高采收率技术,对非均质油藏改善开发效果有借鉴作用。

Ⅴ formation in Shuanghe oil field has already entered the late period of ultra-high water cut,with water cut of up to 95.21%.Because of inner-layer and interlayer heterogeneity of reservoir,between layers there is big difference in production,and the main pay zones are severely flooded.In this paper,the main developing problems in V formation are analyzed,the distance between oil well and water well is big,well-pattern is not perfected,injected water is insufficiently used and injected water absorption profile is asymmetry.Distribution of the remaining oil is established according to oil-water well test and reservoir numerical simulation data.This research indicates that next adjustment direction is remaining oil accumulation area located in the side of formation,adjacent faults and the high remaining reserve regions.Some EOR technologies are put forward,including adjusting and perfecting well-pattern,blocking the larger reservoir pore space in order to adjust profile control,and developing tertiary recovery.After these technologies are used in practice,obvious effectiveness of increasing oil and decreasing water production is achieved,and the water flooding recovery is enhanced.A set of enhanced oil recovery technologies is formed,and it provides a referential evidence for improvement of development effectiveness in the period of ultra-high water cut.