Title: Electromagnetic adsorption and polarization mechanism on reservoir sandstone with nanofluid interaction for oil mobility

Abstract

Using present approaches, improving oil mobility from reservoirs with high temperatures and pressures is unfeasible. As a result, injection of dielectric nanofluid driven by an electric field has been proposed to increase oil mobility in terms of diffusion coefficient and assessment of interfacial tension. When exposed to a direct electric field, nanoparticles are activated, allowing them to travel more effectively and affect oil characteristics. The electronic characteristics of four nanoparticles were simulated and characterized in terms of band structures and partial density of state: zinc oxide, copper oxide, graphene, and magnetite. Following an examination of nanoparticles' influence on oil adsorption energy, two nanoparticles with good dielectric and magnetic characteristics and diverse surface chemistry, Graphene and Magnetite, were chosen. In the preliminary adsorption investigation, oil was represented by Decane and Hexadecene. According to the findings, nanoparticles have a high influence on heavy molecular chains (Hexadecene) and a low impact on low molecular chains (Decane). Magnetite's contact with the rock-oil interface lowered adsorption energy from 23.99Kcal/ mol to 21.63Kcal/mol (for Decane) and from 28.53Kcal/mol to 18.81Kcal/mol (for Hexane) (for Hexadecene). Because Decane had a limited impact, it was employed as an oil candidate in following investigations. In addition, the influence of salinity on the performance of nanoparticles was studied in adsorption research. Salinity increases from 0ppm to 11000ppm (0ppm, 3000ppm, 7000ppm, and 11000ppm) causes additive decrease with a more obvious influence on graphene. Following this, the diffusion coefficient of Decane via a simulated Angsi field sandstone structure was calculated at 120°C after verifying the simulation methods and before and after exposure to the action of nanoparticles and an electromagnetic field. There is a trend in the concentration effect of nanoparticles on Decane diffusivity for Graphene (from 0.01wt percent to 0.05wt percent and 0.1wt percent). Magnetite performed best at 0.05wt percent. The addition of an externally provided electric potential of 2V/cm and 0.05wt percent nanofluid concentration at 11000ppm salinity resulted in increases of 1088.89% and 644.44% for Graphene and Magnetite, respectively. Because interfacial tension is another component that influences the effectiveness of oil mobilization by nanoparticles, the activation of nanoparticles at the interface of oil and water by an electric field was also explored experimentally. The experimental Interfacial Tension findings proved the effectiveness of applied electromagnetic potential in activating nanofluid performance. The application of 2V/cm lowered interfacial tension by 99.49 percent for Graphene and 15.66 percent for Magnetite at the measurement equipment's highest practicable operational heat state of 100oC. Graphene's greater effect can be ascribed to its hydrophobicity and strong dielectric properties.