Self-Limited Accumulation of Colloids in Porous Media

Gaétan Gerber (1) , M. Bensouda (1) , David A. Weitz (2) , Philippe Coussot (1)

1 navier umr 8205 - Laboratoire Navier
2 Harvard University

We present local direct imaging of the progressive adsorption of colloidal particles inside a 3D model porous medium. By varying the interparticle electrostatic interactions, we observe a large range of particle deposition regimes, from a single layer of particles at the surface of the medium to multiple layers and eventually clogging of the system. We derive the complete deposition dynamics and show that colloid accumulation is a self-limited mechanism towards a deposited fraction associated with a balance between the particle interactions and the imposed flow rate. These trends are explained and predicted using a simple probability model considering the particle adsorption energy and the variation of the drag energy with evolving porosity. This constitutes a direct validation of speculated particle transport mechanisms, and a further understanding of accumulation mechanisms.

Mots clés: Flows in porous media; Porous media; Charged colloids; Confocal imaging

Domaines: Matériaux

Gaétan Gerber, M. Bensouda, David A. Weitz, Philippe Coussot. Self-Limited Accumulation of Colloids in Porous Media. Physical Review Letters, 2019, 123 (15), ⟨10.1103/PhysRevLett.123.158005⟩. ⟨hal-02912541⟩