毛管力在低渗透油藏CO_2驱替过程中的作用

针对目前低渗透油藏CO_2驱替过程中,毛管力作用不确定且常被忽略问题,采用室内实验与数值模拟分析相结合的方法,研究了低渗透油藏中毛管力在CO_2驱油过程中的作用。以CO_2在不同驱油方式下长岩心室内实验为基础,建立了一维CO_2驱油的数值模拟模型,并通过模拟分析毛管压力在CO_2不同驱油方式下的作用。研究结果表明,低渗透油藏中,毛管力在CO_2不同驱油方式下所起的作用并不一致,驱替过程表现为动力,压力恢复后的驱替过程表现为阻力。因此,为促进低渗油藏合理有效开发,有效地认清毛管力在CO_2驱油中的作用是必要的。

Effect of capillary pressure on CO2 displacement in low permeability oil reservoirs

In view of the problem that the effect of capillary pressure is uncertain and is often overlooked during CO2 displacement in low permeability reservoirs, the indoor experiment and numerical simulation analysis were combined to study the effect of capillary pressure in CO2 displacement in low permeability reservoirs. Based on long core indoor experiment under different CO2 displacement manners, a 1D numerical simulation model of CO2 flooding was built, and the effect of capillary pressure on the role of different CO2 displacement manners was analyzed through simulation. The research results show that, in low permeability reservoirs, the effect of capillary pressure in different CO2 displacement manners are not consistent. The displacement process is shown as dynamic power, but the displacement process after pressure buildup is shown as resistance. Therefore, in order to promote the reasonable and effective development of low permeability reservoirs, it is necessary to effectively identify the role of capillary pressure in CO2 flooding.