Vol. 7, Issue 1, Part A (2025)

Polymer solutions containing nanoparticles could potentially provide a promising direction for improving the efficiency of oil recovery; however, their exact action and efficiency are still not well-studied. To achieve this objective, a detailed examination of the rheological properties and capillary dynamics (i.e., interfacial tension and contact angle) exhibited by the nanoparticles during oil recovery in polymer processes is conducted in this study. The technique employed includes sequential injection of water, polymer and nanoparticles using synthesized nanosilica (SiO2) as well as nano-aluminium oxide (Al2O3) to evaluate regeneration of crude oil from reservoir rocks under different experimental conditions. The results indicate that water loss is influenced by mobility ratio of polymer-nanoparticles leading into reduction in retention capacity and capillarity strength but increase in viscoelasticity of the polymer itself. Particularly, polymer-SiO2 flooding showed higher percentage of oil recovery than other scenarios whose capillary strength was compromised due to structural breakdown pressure. In addition, when determining relative permeabilities residual saturation (Sor) was found to be 29% while water relative permability (Krw) equalled 0.3%. However, for polymer-nanoparticle mixture, these values were changed into 12% and 0.005%, respectively. The contact angle after the treatment of the polymer was lower, with 21 and 29 degrees, respectively. The addition of the nanoparticles decreased it even more; this should correspond to an increase in hydrophilicity. Beyond the concentration of 2000 mg L−1 of SiO2, no more significant changes were observed. These findings indicate that such a nanoparticle-enhanced polymer solution may serve as a feasible alternative to the more conventional chemical enhanced oil recovery techniques, especially in applications where a shift in oil mobility and increased recovery efficiencies under reservoir conditions are required.