Method for Determining the Amount of Crude Oil Desorbed from Silica and Aluminosilica Surfaces upon Exposure to Combined Low-Salinity Water and Surfactant Solutions

摘要

The desorption of crude oil components from silica and aluminosilicate surfaces upon exposure to low-salinity surfactant solutions was investigated by a quartz crystal microbalance (QCM). The study aimed at facilitating a better understanding of a hybrid enhanced oil recovery (EOR) process, where low-salinity water is combined with surfactant flooding. The measurements were carried out for various concentrations of two sulfonate surfactants: sodium dodecylbenzene sulfonate (SDBS) and sodium dioctylsulfosuccinate (AOT). A procedure for obtaining the oil desorption efficiency (ODE) was developed on the basis of measuring adsorption of surfactants onto the crystals. Generally, the ODE increased when the concentration of surfactants increased. Furthermore, the ODE was lower for aluminosilicate surfaces than for silica surfaces. Contact angle measurements showed wettability alteration toward more water-wet conditions for both crystal surfaces after exposure to low-salinity surfactant solutions.