Ce. Schaefer et al., PREDICTION AND EXPERIMENTAL VALIDATION OF LIQUID-PHASE DIFFUSION RESISTANCE IN UNSATURATED SOILS, Journal of contaminant hydrology, 20(1-2), 1995, pp. 145-166
Citations number
15
Categorie Soggetti
Water Resources","Environmental Sciences","Geosciences, Interdisciplinary
Determination of liquid-phase diffusion through unsaturated soils is i
mportant for estimating contaminant transport in soils and design of r
emediation processes for contaminated soils and groundwater. Liquid-ph
ase diffusion through unsaturated soils is governed by both the pore s
ize distribution and water distribution of the soil matrix. Diffusion
tube experiments were carried out using several soils packed to field
densities to determine the effective diffusivity of chloride ion as a
function of soil moisture content. Chloride was selected to serve as a
non-volatile, non-sorbing tracer species. A transport model was devel
oped to predict liquid-phase tortuosity as a function of readily obtai
ned soil parameters, including density, moisture content, particle siz
e distribution and pore size distribution. The basis of the model was
parallel diffusion resistances in the inter- and intra-particle pore r
egimes. The new model was found to provide an accurate prediction of o
bserved experimental results. Previously reported models did not agree
with experimental results over significant portions of the experiment
al domain investigated.