Study of Interfacial Phenomena of High Asphaltene Crude Oil with Different Salinity Water and ZrO2 Nanoparticles

In recent years, low-salinity waterflooding and nanofluid flooding have been regarded as the new technologies for enhanced oil recovery and research (EOR). Research on the mechanisms behind the improvement in the recovery rate has garnered significant attention. However, little attention has been given to the mechanism of low-salinity water within the high-salinity range and the synergistic mechanism between low-salinity water and nanoparticles. In the salinity range of 0–22,0,000 mg/L, the interfacial properties of different concentrations of Na+, Mg2+, Ca2+, and SO42– were investigated. The following conclusions were drawn: interfacial tension (IFT) gradually decreased at elevated temperatures, reaching a minimum value of 14.9 mN/m for 2000 mg/L low-salinity water at 60 °C. The contact angle decreased significantly at increased temperatures, reaching a minimum value of 64.8° for the contact angle of 2000 mg/L low-salinity water at 60 °C, indicating water-wet wettability. Electrostatic repulsion was the highest for 5000 mg/L low-salinity water, with a zeta potential value of −12.56 mV. Furthermore, Na+ significantly affected IFT and zeta potential values at low concentrations, while Ca2+ exhibited a more significant effect on wettability at low concentrations. Additionally, when utilizing 2000 mg/L low-salinity water as the dispersion medium for ZrO2 nanoparticles, increasing the particle concentration negatively impacted the stability of the nanofluid. As the temperature increased, IFT decreased, reaching a minimum value of 14.27 mN/m at a concentration of 0.01 wt % at 60 °C. Similarly, as the temperature increased, the contact angle decreased, with nanofluids at a concentration of 0.014 wt %, exhibiting the lowest contact angle of 51° at 60 °C, indicating increased water-wet wettability of the rock surface. This study offered a fundamental understanding of interfacial phenomena involving low-salinity water and nanoparticles, indicating their potential for EOR technology.