Simulation of ammonium and chromium transport in porous media using coupling scheme of a numerical algorithm and a stochastic algorithm

摘要

The migration of the species of chromium and ammonium in groundwater and their effectivenremediation depend on the various hydro-geological characteristics of the system. Thencomputational modeling of the reactive transport problems is one of the most preferred tools fornfield engineers in groundwater studies to make decision in pollution abatement. The analyticalnmodels are less modular in nature with low computational demand where the modification isndifficult during the formulation of different reactive systems. Numerical models provide morendetailed information with high computational demand. Coupling of linear partial differentialnEquations (PDE) for the transport step with a non-linear system of ordinary differential equationsn(ODE) for the reactive step is the usual mode of solving a kinetically controlled reactive transportnequation. This assumption is not appropriate for a system with low concentration of species suchnas chromium. Such reaction systems can be simulated using a stochastic algorithm. In this paper,na finite difference scheme coupled with a stochastic algorithm for the simulation of the transportnof ammonium and chromium in subsurface media has been detailed.