大孔道非均质油藏调堵封窜参数优化模拟研究

SSimulation on parameter optimization of profile control and water shutoff in homogeneous formation with channels

注入水沿高渗透大孔道窜流是非均质油藏注水开发后期面临的主要问题之一,多轮次调堵对堵剂注入量、注入位置和剩余油分布的影响缺乏直观描述。为此,设计并加工了不同类型可视化平板模型,系统研究堵剂注入量、注入位置和剩余油分布对规则大孔道地层调堵效果的影响及蚓孔状弯曲大孔道条件下堵剂的最佳注入位置。研究结果表明:对于规则大孔道模型,当堵剂注入量为0.1倍孔隙体积时,其经济效益最佳;且堵剂注入位置越靠近油藏中部,波及改善效果越好;不同剩余油分布情况下堵剂的最佳注入位置不同,当剩余油富集在油井附近时,应优先选择深部堵水;而当剩余油富集在水井附近时,浅部调剖效果更佳;对于蚓孔状弯曲大孔道模型,封堵拐点后端,能较好地发挥高注入压差(流速)与液流转向的协同机理,波及改善效果最好,最终采收率最高。

Water crossflow is one of the main problems encountered during the development of homogeneous reservoirs. Multi-cycle op-erations of water shutoff are short of detailed description. In this paper, the visible plate models are designed, and systematical researchon parameter optimization is launched with ideal modal, while the best position to deploy plugging agents is also studied in modals withbended channels. The results show that there is a limit on the injection volume, and when it equals to 0.1 PV, the operation may get eco-nomical success. The sweep efficiency can be higher with the deeper location, and different styles of remaining oil distribution show dif-ferent results. When the remaining oil is near the producing well, the plugging agents should be put deeper; while the range is littlewith the remaining oil adjacent to injecting well. For models with worm-shaped channels, the best location for plugging agents is just af-ter breakpoint near injecting well, which can make full use of the pressure drop(flowing rate) and fluid diverting. Under this condition,the synergism, aswellasthe recovery rate, can both reach the optimum.