低渗油藏CO_(2)驱提高采收率阶段划分研究

Research on the stage division of CO_(2)flooding for improving oil recovery in low permeability reservoirs

CO_(2)驱油已成为最有效的提高低渗油藏采收率的方法之一,认清CO_(2)驱替过程中原油的驱替规律,是开发好低渗油藏的关键。以低渗油藏CO_(2)驱替长岩心实验为基础,结合数值模拟分析方法,研究CO_(2)驱替过程中原油产出规律。结果表明,原油产出主要可以分为三个阶段:纯油生产阶段、CO_(2)与油混合生产阶段和CO_(2)携带的轻质组分原油生产阶段。

CO_(2)flooding has become one of the most effective methods to improve the recovery efficiency of low permeability reservoirs.Understanding the displacement patterns of crude oil during CO_(2)flooding is the key to developing low permeability reservoirs.Based on the long core experiment of CO_(2)displacement in low permeability reservoirs,combined with numerical simulation analysis methods,the crude oil production law during CO_(2)displacement process is studied.The results indicate that crude oil production can be mainly divided into three stages,pure oil production stage,CO_(2)and oil mixed production stage and CO_(2)carried light component crude oil production stage.