MODELING OF POLLUTANT MIGRATION IN POROUS-MEDIA WITH INTERFACIAL TRANSFER - LOCAL EQUILIBRIUM NON-EQUILIBRIUM/

In the paper, an attempt to model local equilibrium and local non-equi librium in pollutant migration in porous media is presented. Diffusion is assumed to occur in the pores as well as in the solid porous matri x. The macroscopic models are developed using the homogenization metho d (asymptotic expansion technique). The resulting macroscopic equation s show either a one-concentration field or two-concentration fields or memory effects, The domains of validity of all the presented models a re also determined. Local cell problems are provided to compute the ef fective diffusion tensors. The conditions for the local mass equilibri um assumption to be valid are derived in terms of the dimensionless ch aracteristic parameters. The effect of pollutant source distributions is also investigated. (C) 1997 by John Wiley & Son, Ltd.