Contribution of the transport of suspended particles to the internal erosion in soils: Particle migration in porous media

Abstract

National audienceAn experimental study which aimed at investigating the transport behaviour of suspended particles in saturated porous media is presented. A short-pulse technique was used for measuring particle recovery and collision efficiencies in two porous media (silica gravel and glass beads). Breakthrough curves (BTCs) were measured on-line and well described by analytical solution of an advective-dispersive equation with a first-order deposition kinetic. The effects of hydrodynamic and gravity forces on particle transport and deposition rate were delineated. Results show particles travelling faster than the conservative tracer. The recovery rate of the suspended particles decreased with decreasing flow rate, and the deposition rate presents unexpected changes, depending on the flow rate