Macroscopic modeling of colloids adsorption in porous media

Abstract

Natural porous media such as soils or aquifers, contain colloidal particles. Depending on geochemical and hydrodynamic conditions, they can be transported by water, developing high reactivity and mobility. They may therefore act as vectors of pollutants and viruses dissemination in soils and groundwater. Some colloidal particles like bacteria are also likely to present a risk to the environment and health. However, adsorption of colloids on the solid matrix may severely limit their mobility in porous media, consequently, their fate depends on physico-chemical and hydrodynamic conditions. Previous experimental studies [1] highlighted the role of ionic strength and Peclet number on both adsorption and release of particles. The objective of this work is to propose a macroscopic model (Darcy scale) that accurately describes the transport of colloids in the presence of adsorption process observed experimentally.