ONE-DIMENSIONAL PARTICLE TRANSPORT MODEL IN POROUS MEDIA

R.N. Prabhushankar and L.N. Reddi

Department of Civil Engineering, Kansas State University, Manhattan, KS, 66506, 913-532-1586, FAX 913-532-7717


ABSTRACT

The occurrence of migration of colloidal particles through subsurface environments is extensively studied and well acknowledged. Several field studies have indicated the transport of microorganisms and colloidal matter through the subsurface. Therefore, a proper understanding of mechanisms and quantification of particle transport is essential to predict the contaminant migration in ground water. In this work a mathematical model to predict particle transport through porous media is presented. The important feature of this model is the representation of soil matrix as a cluster of pore tubes of different diameters. The effects of various parameters responsible for the particle transport and deposition such as pH, ionic strength, fluid properties, particle density and concentration are accounted for in the model. The effects of these factors are incorporated through the utilization of a single combined parameter.

The effects due to the variation of geometry of the medium and changes in pore size distribution are also taken into account in the model formulation. A numerical solution was obtained by using finite difference scheme to estimate the rate of change of particle concentration and net deposition of particles. The sensitivity analysis of model parameters was also conducted. The main advantages of this model are (1) it incorporates a unique and efficient scheme to account for particle deposition at various spatial and temporal levels; (2) it can be easily modified to estimate facilitated transport of contaminants; and (3) the numerical scheme is simple, and an efficient solution can be achieved without loss of generality.

KEY WORDS

colloids, concentration, density, porous media

This paper is from the Proceedings of the 10th Annual Conference on Hazardous Waste Research 1995, published in hard copy and on the Web by the Great Plains/Rocky Mountain Hazardous Substance Research Center.