Yousef Kazemzadeh

Synergistic effects of nanoparticles (NPs) and smart water flooding are new methods for enhanced oil recovery (EOR). One of the vital issues, in this case, is the formation and stability of emulsion. Therefore, investigating the role and performance of NPs and ions during the processes of EOR, which are based on smart water injection and natural reservoir production, is of significant importance. Previous studies have investigated various factors (i.e., compounds present in oil and water) that affect emulsion stability mainly at ambient temperatures. In this research, the effect of various factors, including the effect of surfactants, salts, and NPs, on the dynamics and thermodynamics of this phenomenon, has been studied through the visual analysis of emulsion droplets under high pressure (HP) and high-temperature (HT) conditions. Based on the results obtained from the experiments, the rate of formation and stability of emulsions increases by increasing the pressure, and after a certain pressure level, it decreases. On the other hand, in general, the rate of emulsion stability follows a decreasing trend by increasing the system temperature. Additionally, in this study, three salts, namely MgCl2, CaCl2, and NaCl, and two surfactants, AOS (alpha olefin sulfonate) and CTAB (cetrimonium bromide), were used. After finding the optimal weight percentage of these salts and surfactants in the formation and emulsion stability, they were combined with nanoparticles of silica oxide in different volume percentages, and the effect of these nanoparticles on the emulsion stability was investigated. The effect of ultrasonication on solutions containing NPs was also investigated from the point of view of emulsion formation and stability. Based on the results obtained, as the power consumption of the ultrasonic device increases to form an emulsion, the rate of rotation for its separation will also increase.