Fluid-solute-colloid interactions in porous media and its implications for enhanced oil recovery

Flows of colloidal suspensions containing a variety of solutes in porous media are widely found in nature as well as artificial settings such as hydrocarbon recovery, blood flow, water purification, and coastal habitats. Such environments often exhibit spatiotemporal inhomogeneity in the solute and colloid distribution. While it is naively expected that the colloidal particles advect with the flow, non-equilibrium interactions between the fluid, solute, and the colloids may lead to unique colloidal dynamics. We present a number of scenarios in which the colloidal particles can be captured and accumulate continuously in localized regions in porous media despite the presence of strong pore flow due to the fluid-solute-colloid interactions. We link our findings to the chemical flooding process to provide useful insights into the enhanced oil recovery.