The Impact of Nanoparticles Adsorption and Transport on Wettability Alteration of Water Wet Berea Sandstone

Abstract

AbstractWettability alteration was proposed as one of the main Enhanced Oil Recovery (EOR) mechanisms for nanoparticle fluid (nanofluid). A series of wettability index measurement experiments were conducted for water wet core plugs, which were treated by nanofluids with varied nanoparticles concentrations and types of nanoparticles. Nanoparticles transport experiments with the same nanofluids also were performed to study nanoparticles adsorption behavior. Effluent nanoparticles concentration was measured to evaluate nanoparticles adsorption and desorption inside core. Pressure drop was recorded during nanoparticles transport process to show effect of adsorption on permeability. Wettability index measurements were also performed for hydrophobic nanoparticles to investigate its effect on wettability.The results of wettability alteration experiments indicated that hydrophilic nanoparticles have ability to make the core more water wet but not significantly. Hydrophobic nanoparticles can delay spontaneous imbibition while cannot change original wettability. For nanoparticles transport experiments, the results showed that the nanoparticles undergo both adsorption and desorption during injection. Effluent nanoparticles concentration curves were plotted to find breakthrough time. Experiments with varying concentration and type of nanoparticles showed different adsorption and desorption ability for water wet core. Permeability impairment was observed during nanoparticles dispersion injection.This experimental study combined the effect of adsorption and transport of nanoparticles inside Berea sandstone on wettability alteration and permeability impairment. The objective of this paper is to release the influence of nanoparticles adsorption and transport on EOR of nanofluid.