Determination of CO2/crude oil system interfacial tension and dynamic interfacial tension by ADSA method

ADSA was used to measure the interfacial tension of CO2/crude oil system under simulated-formation conditions of temperature of 355.65K and pressure ranging from 7MPa to 23MPa. The test results indicated that the equilibrium interfacial tension of CO2/crude oil system decreased as the systematic pressure increased. Intense mutual diffusion happened when CO2 was in contact with crude oil. CO, extracted the light components of crude oil and was constantly dissolved in the crude oil, both processes ultimately achieving homeostasis. The dynamic interfacial tension between CO2 and crude oil was large at the initial contact. After that, the interfacial tension gradually decreased, and finally reached dynamic balance. In addition, the interfacial tension of the CO2/crude oil system decreased greatly with time as the systematic pressure increased.