CO_2气窜主控因素研究

The Research on Main Controlling Factors of CO_2 Gas Channeling

在CO2驱油过程中,气窜的发生是一个必然现象,只是不同条件下其窜流程度不同。目前对窜流规律及其控制方法的研究已经成为国内外关注的焦点。讨论了渗透率、驱替速度、裂缝对CO2突进的影响,并进行了CO2与N2驱油突进对比。进一步明确在相同注入条件下,CO2在特低渗储层中的窜流比N2要弱;与N2相比,CO2更容易进入致密的低渗层,有利于低渗层剩余油的动用。

During the oil flooding process, the occurrence of gas channeling is an inevitable phenomenon. However, degrees of the channeling process are different under different conditions. Channeling laws and its control methods have become the focus of attention at home and abroad. The influence of permeability, displacement veloc- ity and cracks are discussed on the onrush of C02, and make comparisons on flooding onrush between CO2 and N2. Further clarify that in the same injection conditions, the channeling of CO2 is weaker than N2 in the ultra-low permeability reservoirs. Compared with N2, CO2 is easier to the producing of remaining oil in low-permeability layer.