超临界二氧化碳混相驱油机理实验研究

Laboratory study on miscible oil displacement mechanism of supercritical carbon dioxide

根据大庆榆树林油田原油组分变化、CO2与原油界面张力关系及CO2超临界性质,对CO2混相驱地层情况进行了模拟研究,建立了CO2混相驱驱替模型和方程。研究结果表明,超临界状态的CO2可以降低所波及油水的界面张力;混相时混相带原油含碳组分中C20以下的含量达到了最高值;水气交替注入时,水对混相有不利的影响。

On the basis of component change of carbon in oil, interracial.tension between oil and carbon dioxide and the quality of supercritical carbon dioxide of Yushulin oil fields in Daqing area, the formation change of carbon dioxide miscible oil displacement was simulated. The model of carbon dioxide miscible flooding in these oil fields was established, and the equation of carbon dioxide miscible flooding was found. Some new and important mechanisms on the craft mode of carbon dioxide miscible flooding and the water-gas alternating injection were determined. The supercritical carbon dioxide could lower the tension of the interface of involved oil and water, and the content of carbon dioxide in carbon component of oil could reach the highest value in the miscible region. The effect of water on the carbon dioxide miscible flooding is unfavorable for the alternating injection of water and carbon dioxide.