Colloidal control of multi-phase flow in geological porous media

Introduction

The COCONUT project aims at developing predictive capabilities to understand how colloids (nanometals, fine particles, bacteria, viruses, asphaltenes, etc.) control immiscible two-phase flow in complex geological formations.

Potential of Colloids

Colloids (including nanoparticles) have an incredible potential to remobilize non-aqueous phases trapped by capillary forces in soils and the subsurface. This capability can be utilized for:

• Remediating contaminated groundwater
• Enhancing oil recovery

However, their use in daily engineering is still underexploited due to the lack of knowledge regarding their transport mechanisms, which poses an obstacle to precise control of two-phase flow.

Challenges in Modeling

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.

Project Strategy

The COCONUT project employs a combined modeling-experimental strategy focusing on:

1. Pore-scale mechanisms
2. Upscaling to the continuum scale

Multi-disciplinary Approach

The project is multi-disciplinary and utilizes:

• Computational and experimental sciences
• Fluid dynamics
• Electrochemistry
• Mathematics

Work Packages

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 modeling and microfluidic experiments (WP3).

Finally, we will demonstrate and optimize the two-phase flow colloidal control in geological systems at the column scale (WP4).