水平井二元复合驱三维油藏物理模拟研究

为研究水平井二元复合驱提高石油采收率的渗流机理,建立了三维纵向非均质物理模型,利用模型上布置的饱和度测量探针,测量了水平井二元复合驱的开采效果、进口压力和饱和度场变化。实验结果表明:对于纵向非均质油藏,二元复合体系在油藏内的吸附、滞留、乳化等作用使阻力增大,压力升高,液流转向,波及范围扩大;在平面上,在二元体系的协同作用下,驱替出水驱波及域外和簇状剩余油;在水平井、重力和正韵律"低渗透屏障"作用下,注入的流体优先流动到高渗层,再由高渗透层向中、低渗透层渗流,提高了纵向波及范围。因此,水平井二元复合驱可以大幅度提高原油采收率。

3-D physical modeling of enhanced oil recovery by surfactant-polymer flooding in horizontal well

The fluid flow mechanism in porous media of EOR by the surfactant-polymer flooding in horizontal wells was investigated by measuring production performance, input pressure and saturation distribution with saturation measuring probes in a 3-D physical model of vertical heterogeneous reservoir. Results show that, in a vertical heterogeneous reservoir, with the resistance increasing and the pressure going up, the flow direction changed under the physical and chemical actions of adsorption, retention and emulsion of SP agents in the reservoir. The SP agents displaced the remaining oil that water flooding did not affect and clustered remaining oil in the plane direction. Under the action of horizontal well, gravity and positive rhythm “low permeability barrier”, the fluid mainly flew in high permeability regions, and then flew from high permeability layer to the middle, last to low permeability regions which enlarged sweeping volume. So, the surfactant-polymer flooding in horizontal well can greatly enhance the oil recovery.