氮气泡沫热水驱物理模拟及数值模拟研究

Research on physical and numerical simulation of nitrogen hot-water foam flooding

针对强非均质油藏提高采收率的需要,开展了泡沫驱油技术研究。利用油田现场提供的起泡剂和原油等资料,通过室内物理模拟和数值模拟,对氮气泡沫热水驱提高采收率的机理进行了研究。建立了三维、三相、多组分数学模型,编制了氮气泡沫热水驱油藏数值模拟软件。模型考虑了相平衡以及温度、界面张力对油、气、水三相渗流的影响以及起泡剂损失的各种机理,较全面地反映了氮气泡沫热水驱的作用机理。实验和数值模拟的结果均表明,氮气泡沫热水驱能大幅度地提高驱油效率,降低残余油饱和度。在非均质油层(模型)中泡沫的驱油效果比在均质油层(模型)中更好,残余油饱和度降低了21.1%,采收率提高了31.2%。

Technology of foam flooding is studied for the purpose of enhancing oil recovery in oil reservoirs of high heterogeneity.Based on using the materials of foaming agents and crude oil obtained from oilfields,this paper studies the mechanism of nitrogen hot-water foam flooding enhancing oil recovery using physical simulation and reservoir simulation.A three-dimensional,three-phase,and multiple-component model is developed,and the software for three-dimension,three-phase,and multiple-component reservoir simulation is established on the basis of modularization theory.Phase equilibrium and effects of temperature and interfacial tension on multiple-phase flow in porous media are taken into account in the model,and the model can comprehensively describe the mechanisms of nitrogen hot-water foam flooding.The results of experiment and simulation show that the nitrogen hot-water foam flooding can significantly enhance displacement efficiency,lowering the remaining oil saturation.It is more effective for heterogeneous formations rather than for homogeneous ones,since the residual oil saturation is reduced 21.1%,while oil recovery is increased by 32.1%.