Numerical Solution of the Pollutant’s Penetration in a Specific Soil in Tensift (South Morocco)

Abstract

Studies of pollution in porous media as well as water transfers in unsaturated soils have concerned many researchers. These studies have intensified, since it has become apparent that soils could have an impact on the environment, flora and fauna. In this work, the process of pollutant’s propagation in an unsaturated, with a variable porosity, and broken media has been studied. The flow of fluids in such media is modeled by the Richards equation coupled by the pollutant transport equation and by the equation of thermal transfer. Those equations have been complemented by empirical relationships in order to describe the relationships between fluid pressure, and relative permeability. Because of the strong non-linearity of the equations, the double continuum method has been adopted to discretize the system of equations obtained. For the resolution, the method of ADI (Alternating Direction Implicit) has been used. Then, several graphics have been plotted in order to understand the role of three main parameters: Pressure, Temperature and Concentration. The conclusion reached is that the pressure decreases through time mainly because of the infiltration of the pollutant inside of the matrix of the media. The temperature decreases through time, which means that the heat transfer is amortized over time. The concentration of the pollutants increases over time, which is explained by the accumulation of products of dissolution of pollutants. The originality of this work is the development of a numerical solution in order to solve the flow of the pollutants for such media. Then, it has been applied on a specific region of South Morocco: Tensift.