关键词: 三元复合驱, 界面张力, 粘度, 乳化, 润湿性, 驱油效率

Abstract: On the basis of core physical simulation experiment and micro-displacement experiment, influential rule and mechanism of interfacial tension, viscosity of ASP system, formation of emulsified oil droplet coalescence and reservoir rock wettability on ASP displacement efficiency have been analyzed. The result showes that improving water/oil balance and reducing dynamic interfacial tension can greatly increase ASP displacement efficiency and oil/water interfacial tension must be lower than 10^-3 mN/m magnitude order by ASP flooding. In addition, increasing viscosity of ASP system can enlarge ASP swept volume, with necessary condition of water/oil viscosity ratio more than 2 for improving oil recovery by 20% by ASP flooding. As emulsified oil droplet formation is the main way to enhance ASP displacement efficiency,the lower water/oil interfacial tension is,the higher viscosity of displacement system is; the easier producing emulsified droplet energy is,the better displacement efficiency is. Moreover, ASP flooding can displace oil-film on the surface of oil-wet rock and change rock wettability from oil-wet to water-wet.

Key words: ASP flooding, interfacial tension, viscosity, emulsification, wettability, displacement efficiency