INITIATION OF THERMAL ENERGY IN AN OIL-SATURATED POROUS MEDIUM

One of the directions in the development of chemical thermal energy has been explored, particularly regarding the provision of energy carriers through the efficient extraction of residual oil reserves from fields at a late stage of development. The focus is placed on the use of thermochemical effects, specifically the exothermic reaction of granulated magnesium with hydrochloric acid solution, to initiate thermal energy directly within the oil-saturated porous medium. This process yields a sufficient amount of thermal energy and enhances the extraction of residual, hard-to-recover oil reserves. An improved design of a high-pressure autoclave is proposed for studying the kinetics of exothermic reactions under conditions close to actual reservoir environments — pressures up to 50 MPa and temperatures up to 150 °C. The results of experimental studies on the influence of pressure on the reaction kinetics and the efficiency of thermal energy generation are presented. It is confirmed that as pressure increases, the dissolution rate of magnesium decreases due to the formation of a hydrogen gas shell around the magnesium granules, which hinders the diffusion of reactants. An empirical equation describing the dependence of the reaction rate on pressure has been obtained, and the dynamics of temperature change in the reaction zone under reservoir-like conditions typical of active oil fields in Ukraine have been studied. The research results demonstrate the potential of using thermochemical reactions to initiate thermal energy within oil-saturated porous media. The conducted studies form the basis for further research and the development of technological processes aimed at using thermal energy to maximize hydrocarbon recovery and ensure Ukraine’s energy sustainability. Bibl. 25, Fig. 3.