低渗透油藏分段压裂水平井开发方式研究

Study on Energy Supplement of Low Permeability Reservoirs With Fractured Horizontal Wells

目前油田分段压裂水平井大多处于弹性开采阶段,产量递减快,迫切需要选择合适的开发方式来补充地层能量;国内外关于分段压裂水平井开发方式的选择目前还研究较少。根据现场某水平井示范区的地质资料建立了五点法分段压裂水平井井组模型,采用组分模拟分别开展了三类低渗透储层在衰竭、注水、注气及水气交替4种开发方式的研究,并利用大型高压物理模拟试验验证了数值模拟结果的可靠性。研究结果表明:Ⅰ类和Ⅱ类储层适合注水开发,Ⅲ类储层适合注气开发,水气交替能有效缓解含水上升和气窜,提高采出程度。

Currently most of fractured horizontal wells in oilfields were developed in elastic recovery. It is urgently needed to supply formation energy because of the fast production and pressure decline. There was less study on the development style optimization of fractured horizontal wells. In this paper, a five-spot model of horizontal wells was built based on a certain horizontal wells demonstration area. Compositional Simulation were applied to study on the effectiveness of four development methods for three types of low permeability reservoirs with fractured horizontal wells, and the simulation results of the II class formation was proved by physical experiments. The study showed that., the I class formation and the II class formations are better applied with water injection as well as the III class formation is better applied with gas injection. WAG can enhance oil recovery by delaying water cut increasing and gas channeling. Reasonable suggestions were proposed for three types of low permeability reservoirs for fractured horizontal well development.