Simulating thermal remediation in porous media

Remediation techniques involving thermal treatment technologies, such as thermal conductive heating, are effective at removing non-aqueous phase liquids (NAPL) from soils. In this process, co-located cylindrical heaters and extractors are placed in the soil. As the soil heats up, the contaminants vaporize and are removed by the extractors. In this thesis, we present a numerical model for the remediation of contaminated soil. This numerical model couples a continuum model of the temperature in the soil with a macroscopic invasion percolation (Macro-IP) model to capture the dynamics of the gas migration. The heat transport is modelled using a finite difference scheme and macro-IP uses constitutive relations to describe the fluid and gas phases. Finally, we compare the results of the Macro-IP model with a simpler Stefan problem in one dimension. The results show that the dynamics of the NAPL front are primarily determined by the time the location reaches a depth-dependent temperature, and only weakly on the amount of NAPL initially present. Moreover, it is unclear whether the additional model fidelity provided by including the Macro-IP step is necessary to make reasonable predictions of how long the heaters need to run.