高凝油油藏气水交替驱提高采收率参数优化

通过开展室内物理模拟实验,验证了高凝油油藏气水交替驱提高采收率的可行性,得到了岩心尺度下的最优化参数,采出程度较纯水驱时提高19.83%。在物模研究的基础上,利用实验岩心和流体参数、含气活油相渗曲线建立数值模型,分别研究注采井网、注采井距、段塞尺寸、气水体积比、注入时机、注入周期各参数对采收率的影响。研究结果表明:当采用五点系统、300 m井距、0.2PV段塞尺寸、1∶2气水体积比、含水率60%时转注、连续注入9个周期为最佳方案,可以保证在较低的注气成本下获得较高的采收率,对以后该类油藏的气水交替驱开发具有理论指导意义。

Parameter optimization of WAG flooding for improving oil recovery of high pour-point oil reservoir

Physical simulation experiments were carried out to verify the feasibility of water alternating gas (WAG) flooding for improving oil recovery of high pour-point oil reservoir.And then optimal parameters on core scale were ob-tained.The increased recovery of WAG is 19.83% higher than that of waterflooding.Based on the physical simulation re-search,the numerical simulation model was established according to parameters of core and fluid,and relative permeability curve of live oil.And then it was carried out the effect of well pattern,well spacing,slug size,gas water volume ratio,injec-tion timing,and injection cycle on oil recovery rate.The results showed that the preferred plan includes five-spot well pat-tern,300 m well spacing,0.2 PV slug size,1∶2 gas water volume ratio,injection timing at 60%water cut,continuous injec-tion of nine cycles,which guarantee higher oil recovery ratio under the condition of low gas injection cost.Thus this has guiding significance to WAG flooding for this kind of reservoir.