Colloidal control of multi-phase flow in geological porous media – COCONUT

The COCONUT project aims at developing predictive capabilities to understand how colloids (nanometals, fine particles, bacteria, viruses, asphaltenes..) control immiscible two-phase flow in complex geological formations. Colloids (including nanoparticles) have an incredible potential to remobilize non-aqueous phase trapped by capillary forces in soils and the subsurface, and then to remediate contaminated ground-water or enhance oil recovery. Their use in daily engineering, however, is still underexploited because the lack of knowledge regarding their transport mechanisms is an obstacle to precise control of two-phase flow. Importantly, the presence of colloidal particles flowing in the subsurface challenges the standard modeling viewpoint of flow and transport based on Darcy’s law. We posit that the precise control of colloids on the motion of two-phase flow can only be achieved by developing a deep knowledge of the coupled hydro-electro-chemical processes at the pore-scale. The COCONUT project uses a combined modelling-experimental strategy focusing on the pore-scale mechanisms and on the upscaling to the continuum-scale. The project is multi-disciplinary and uses computational and experimental sciences, fluid dynamics, electrochemistry, and mathematics. The project will require the development of hydro-electro-chemical computational models at different scales of interest (WP1). We will use high-resolution simulations to interrogate emergent physico-chemical processes and characterize the surface attractive and repulsive forces at the nanoscale (WP2). Then, we will decipher the mechanisms leading to the displacement of fluids trapped in an unsaturated porous medium in the presence of colloids using pore-scale modelling and microfluidic experiments (WP3). Finally, we will demonstrate and optimize the two-phase flow colloidal control in geological systems at the column-scale (WP4).