EXPERIMENTAL DETERMINATION OF SOLUTE TRANSPORT PARAMETERS OF SAND MEDIA

Abstract

Ground water is no doubt the greatest and most important natural source of water supply, but increasing industrial, nuclear and domestic wastes being dischared into the aquifers pose a serious problem of its. pollution. It was generally felt that passage of polluted water through porous media would purify itself. However, it has been found that purifying action has its limitations. In order to prevent or minimize such a water pollution problem, a thorough understanding of the flow and solute transport mechanism along with the associated parameters is essential. In present study, investigation is concerned with the dispersion of chemical pollutant. The experiments were conducted using a perspex column, 117 cm. long with 10 cm x 10 cm square cross section filled with sand media. Sodium chloride (NaCl) was used as chemical pollutant to study the time variation of salt concentration, samples were collected, and conductivity was measured. The dispersion coefficient and porosity were estimated for different location and for different sand samples. A linear increasing trend of dispersion coefficient with respect to length of flow has been found. A linear decreasing trend of dispersivity of the medium with respect to increase in average grain size of medium has also been observed.