Mathematics of Pesticide Adsorption in a Porous Medium: Convective-Dispersive Transport with steady state water flow In two Dimension

Abstract

The transport of solutes through porous media where chemicals undergo adsorption or change process on the surface of the porous materials has been a subject of research over years. Usage of pesticides has resulted in production of diverse quantity and quality for the market and disposal of excess. material has also become an acute problem. The concept of adsorption is essential in determining the movement pattern of pesticides in soil in order to asses the effect of migrating chemical, from their disposal sites, on the quality of ground water. In the study of movement of pesticides in the soil, the mathematical models so far developed only consider axial movement. The contribution of radial movement to the overall location of solutes in the porous media seems to have been disregarded by researchers in this field. The objective of this study is to close this gap by developing a mathematical model to determine the combine radial and axial movement of pesticides due to Convective - Dispersive transport of pesticides with steady - state water flow in a porous media. The methodology will involve determining the comprehensive dispersion equation accounting for both axial and radial movement of solutes in the porous media and finding the solution of the governing equation using finite difference methods. The solution of this equation will be applied to the data from experiments carried out on adsorption and movement of selected pesticides at hi~h concentration by soil department, University of Florida, Gainesville U.S.A. We will confme our study to single - Region Flow and Transport.