油藏条件下溶解CO2的稀油相特性实验研究

以胜利大芦湖油田樊 12 4区块稀油油藏为例 ,利用高温高压PVT物性分析仪 ,通过CO2 对地层油的膨胀降粘、多次脱气和多次接触实验 ,研究了用不同量CO2 饱和的稀油相特性 ,给出了大量CO2 溶解引起的原油相特性参数的变化规律 ,解释了CO2 驱提高原油采收率的机理。实验结果表明 ,CO2 可有效地使地层原油膨胀 ,改善原油的流动特性。同时还可大量萃取地层油中的轻烃 ,使气相不断富化 ,从而达到动态混相 ,最终提高原油采收率。

Phase behaviors of light oil with dissolution of CO2 under reservoir condition

Taking the light oil reservoir of Fan-124 block in Shengli-Daluhu Oilfield as an example, the mechanism of enhanced oil recovery by the use of CO_2 gas drive was investigated. The pressure-volume-temperature (PVT) property analysis instrument was used to analyze the behaviors of light oil with different amounts of CO_2 gas. The effect of CO_2 gas expansion on viscosity reduction of reservoir oil, the multiple-degasification from oil and the multicontacting in reservoir oil were experimented. The change of the phase behaviors of crude oil caused by abundant dissolution of CO\-2 gas was described. The experimental results show that CO_2 gas can make oil expand and improve flow behavior of oil. It also can extract the light hydrocarbon of crude oil, enrich gas phase and achieve the dynamic miscible to improve oil recovery.