Numerical model of the migration of toluene in porous media

Abstract

A Volatile Organic Compound (VOC) model describing migration of toluene concentration in subsurface system of porous media was developed. To investigate pollutant transport of nonaqueous phase liquids (NAPL) for VOC, requires a solution of multiphase fluid flow, heat flow and pollutant transport in a deforming porous media. The nonlinear saturation and relative permeability functions were incorporated into Galerkin finite element model, which was subsequently used to simulate multiphase immiscible fluid flow under unsaturated conditions. The governing partial differential equations, in terms of soil displacements, fluid pressures, concentrations and temperature, which are coupled and non¬linear, are solved by the finite element method. The weighted residual finite element approach was employed to achieve spatial discretization of the problem while temporal discretization was achieved by a fully implicit scheme. The potential use of the numerical model is discussed and applied to toluene migration in one-dimensional analysis to demonstrate the model capabilities.