Abstract

This study aims at investigating, experimentally and numerically, the pesticide transport through the soil in unsaturated zone. In our work the multi residues GC 250 (Metribuzin) and LC 250 (Isoproturon) are studied. The movement of pesticide is described with one dimensional model. The transport equation incorporates terms accounting for diffusion – convection, adsorption and reaction. The first objective of this work is to identify the effects of the parameters transport such as: the dimensions first order degradation coefficient (), the peclet number (e) and the dimensionless mass transfer coefficient(w). The evolution of pesticide concentration in fuction of depth and time was found by using the non-equilibrium transport model. The data obtained show the importance of the adsorbed concentration. The second objectif is to find the relation between the concentration and the transport parameters because there is a difficulty of the analytical solution. The third objective is to find a new form for the Non-equilibrium model of two-dimensional dispersion (2D), with the consideration the two velocities horizontal and vertical. days, shows that the vertical velocity V higher than the horizontal velocity U.The results have been analyzed to understand these processes for possible improvement .We were able to predict the time behavior of a contaminated groundwater layer and the distribution and rate of pollutant penetration into soil . Maximum concentration of pesticide (29% from the initial concentration C0) in the soil appears one hundred days after application at 100-m depth. We can be used to value a window of occasion for emergency action. The results obtained are agreed with those of other authors who treat with the same problem. The solution of the problem was carried out by a numerical approach by using the finite difference method and the finite volume method with the aid of the FORTRAN program.

Information

Item Type:	Thesis
Divisions:	» Laboratory sciences and technical water and environment » Faculty of Science and Technology
ePrint ID:	1837
Date Deposited:	2019-06-24
Further Information:	Google Scholar
URI:	https://www.univ-soukahras.dz/en/publication/article/1837

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