NUMERICAL MODEL OF THE MIGRATION OF TOLUENE IN POROUS MEDIA
DOI:
https://doi.org/10.11113/mjce.v15.15655Keywords:
Groundwater, Unsaturated Zone, Finite Element, Toluene, Multiphase Flow, Heat and Volatilisation.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 capabilitiesReferences
Brooks, R.H. and Corey, A.T. (1964) Hydraulics properties of porous media. Hydrology Paper 3, Colorado State University, Fort Collins.
Dorgaten, H.W. and Tsang, C.F. (1992) Three-phase simulation of organic contamination in aquifer systems. In K.U.Weyer (ed), Proc. Int. Conf. on Subsurface Contamination by Immiscible Fluids, Calgary, Canada, Rotterdam: Balkema, 149-158.
Ferguson, W.J. and Thomas, H.R. (1997) A numerical study of the effect of thermal gradient on landfill gas migration. In R.N. Yong and Thomas (eds.), Proceedings of the Conference on Geoenvironmental Engineering - Contaminated ground: fate of pollutants and remediation. London: Thomas Telford, p. 181-186.
Fredlund, D.G. and Rahardjo, H. (1993) Soil Mechanics for Unsaturated Soils. New York: John Wiley and Sons.
Jury, W.A., Spenser, W.F. and Farmer, W.J. (1983) Behavior assessment model for trace organics in soil: 1. Model Description. Journal of Environmental Quality, 12: 558-564.
Lewis, R.W. and Schrefler B.A. (1987) The Finite Element Method in the Deformation and Consolidation of Porous Media. Chichester: John Wiley.
Lujan, C.A. (1985) Three-Phase Flow Analysis of Soil Spills in Partially Water-Saturated Soil. Ph.D thesis, Department of Civil Engineering, Colorado State University, Fort Collins.
Millington, R.J. and Quick, J.P. (1961) Permeability of porous solids. Transactions of the Faraday Society, 57: 1200-1207.
Muhammad Nassir, H. (1991) Long Term Simulation of Water and Vapor Phase Transport in Unsaturated-Saturated Soil. Master Thesis, University of Waterloo, Ontario, Canada.
Norhan, A. R. (1998) Finite Element Analysis of Multiphase Flow Heat Flow and Pollutant Transport in Deforming Porous Media for Subsurface System. Ph.D. Thesis, University Of Wales, Swansea.
Norhan A. R. and Lewis, R.W. (1997) Numerical modelling of multiphase immiscible flow in deforming porous media for subsurface system. In R.N. Yong and Thomas (eds.), Proceedings of the Conference on Geoenvironmental Engineering –Contaminated Ground: Fate of Pollutants and Remediation. London: Thomas Telford, p. 254-263.
Zainab M.Y. (2002) Numerical Modelling of Volatile Organic Compounds in Subsurface Systems. Master Thesis, Universiti Teknologi Malaysia, Skudai, Johor.
