水驱油藏相对渗透率曲线变化规律研究

Change Rules of Relative Permeability Curve of Water-drive Reservoir

针对高含水油田水驱开发过程中相对渗透率曲线变化造成油藏流体流动描述困难的问题,通过水驱实验设计,得到水驱油藏相对渗透率曲线变化规律。结果表明,在长期水冲刷后,岩石的孔隙结构及润湿性会发生不同程度的变化,因而相对渗透率曲线必然也会发生变化。长期水冲刷岩样亲水性变强,并且相对渗透率曲线形态与原始的相对渗透率曲线发生变化,因此在高含水后期进行开发储量计算、三次采油研究时,应考虑水驱后相对渗透率曲线变化特征。该规律可应用于油藏数值模拟中,为开发后期井网调整进行有效指导。

In view of the difficulty in describing reservoir fluid flow caused by the change of relative permeability curve during water-drive development of high water content oilfield, the change rules of relative permeability curve of water-drive reservoir were obtained through water-drive experiment design. The results show that the pore structure and wettability of rocks will change in varying degrees after long-term water scouring, so the relative permeability curve will inevitably change. The long-term water washed rock samples become more hydrophilic, and the shape of the relative permeability curve changes with the original relative permeability curve. Therefore, the change characteristics of the relative permeability curve after water flooding should be considered when calculating the development reserves and studying the tertiary oil recovery in the late stage of high water content.These rules can be applied to reservoir numerical simulation and effectively guide well pattern adjustment in late development.