致密油水平井小型注水吞吐技术研究

Research on small-scale water injection huff and puff technology for horizontal well of tight oil

目前致密油水平井开发过程中,常规注水适应性差,自然能量开发递减大,水平井低产低效,整体采出程度低,迫切需要对水平井有效补能技术进行攻克,来实现恢复单井产能,提高采收率。D1区C7油藏为一个致密油水平井开发单元,受裂缝发育、井间干扰大、注水适配性差等因素影响,长期无注水补能,自然递减持续较高,开发水平低。针对此问题,前期开展了水平井长周期注水吞吐和压裂车快速分段注水吞吐矿场试验,取得了一定效果,但存在注水有效利用低的问题,投入高产出低。通过研究两种试验机理,结合实际情况,摸索出了小型快速注水吞吐技术,增油效果较好,为同类油藏开发具有现实指导意义。

At present,in the process of horizontal well development of tight oil,conventional water injection adaptability is poor,natural energy development is decreasing,horizontal well is low production and low efficiency,and the overall recovery degree is low.It is urgent to overcome the effective energy supplement technology for horizontal wells to restore single well productivity and enhance oil recovery.C7 reservoir in D1 area is a horizontal well development unit of tight oil.Due to the development of fractures,large interwell interference and poor water injection adaptability,there is no water injection for a long time,the natural decline is high and the development level is low.In order to solve this problem,the field tests of long-period water injection and stimulation in horizontal wells and the rapid subsection water injection huff and puff by fracturing vehicle have been carried out in the early stage,and some results have been achieved.But there is a problem of low effective utilizaton of water injection and high input.By studying the mechanism of the two tests and combining with the actual situation,the small-sized fast water injection huff and puff technology is found out,which has a good effect of increasing oil,and has practical guiding significance for the development of similar reservoirs.