QCM-D Study - Adsorption and Desorption of Crude Oil on Silica and CaCO3 Surfaces
Interactions between crude oil and reservoir materials are complex, and industrially very important. There is clearly a need to investigate the interactions as they can be used for understanding enhanced oil recovery (EOR) processes. In this study, oil recovery from silica and calcium carbonate substrates was investigated in order to mimic the oil recovery from sandstone and calcite reservoirs.
Increased oil recovery by substantially lowering the injection brine salinity or modifying the brine composition of the injection water has been reported in numerous experimental studies and field trials for both tertiary (residual oil condition) and secondary (initial water condition) modes of water flooding.
Quartz crystal microbalance with dissipation (QCM-D) has been used to investigate adsorption and/or desorption of crude oil fractions, asphaltenes on hydrophilic surfaces. The effects of ions, ionic strength, and salinity on EOR processes were investigated by QCM-D. The studies show that QCM-D is able to monitor various structural arrangements of adsorbed materials can be used to understand how oil components adsorb to surfaces.
In this study, oil recovery from silica and calcium carbonate substrates was investigated in order to mimic the oil recovery from sandstone and calcite reservoirs. The effects of brines, NaCl and CaCl2, in EOR processes were studied by QCM-D. Our study shows that high salinity brine (3.3% NaCl and CaCl2) cannot increase oil recovery from silica surface but it increases oil recovery from calcium carbonate surface, while low salinity brines (1600 ppm NaCl and CaCl2) increase oil recovery from both silica and calcium carbonate surfaces.