Numerical Modeling for Simulation of Contaminant Migration of Leachate in Soil Media

TL;DR

This paper develops and compares numerical and analytical models to simulate the migration of leachate contaminants in soil layers beneath landfills, demonstrating good agreement with experimental data and potential for field application.

Contribution

It introduces a finite element numerical model with variable diffusion coefficients and boundary conditions for simulating leachate contaminant transport in soil.

Findings

Numerical results closely match experimental data.

The model effectively simulates ion transport in landfill leachate.

Good agreement validates the model's use for environmental impact assessment.

Abstract

Solid waste disposal in a landfill causes leachate production whose discharge to soil layers carries soil and leachate contaminants to the groundwater. A landfill with a capacity of 3000 ton/day and an area of 0.5 square kilometers is studied to assess and control the environmental impacts of leachate discharge on the inner layers of soil. An analytical calculation is performed, a numerical model under two different boundary conditions is developed, and their outcomes are compared to the experimental values. The landfill data is used for programming and a finite element modelling is applied. The variables considered in the model are time steps and diffusion coefficient. Results obtained from numerical computations were compared with the experimental values. The comparison demonstrates a good agreement between experimental and numerical calculations. This model can be used at fields for the landfills to simulate transport of different types of ions available in the leachates in any scale.