On the use of foam for the in situ remediation of polluted heterogeneous soils

Abstract

In this paper we present an experimental study of foam flow in porous media dealing with 1D sandpacks columns and 2D laboratory pilot. 1D porous column were dedicated to the study of foam generation and propagation in porous media of different permeabilities. We show that the resistance factor (RF) to flow, that is the ratio between pressure drop in presence of foam and pressure drop in absence of foam, is a non-monotonous function of permeability. A 2D transparent laboratory pilot (1 × 0.5 × 0.02 m3), made of two water saturated sand layers of different permeabilities has been used to visualize foam flow. We clearly see that foam remains in high permeability layer and does not enter in the low permeability one. Moreover when we inject a liquid tracer we see that fluid velocities are quite similar in both layers showing the front straightened up.