HOMOGENIZATION ANALYSIS OF DIFFUSION AND ADSORPTION MACROTRANSPORT IN POROUS-MEDIA - MACROTRANSPORT IN THE ABSENCE OF ADVECTION

A model for pollutant transport in a heterogeneous medium, including diffusion accompanied by adsorption, has been developed. The macroscopic equivalent diffusion tensor and the macroscopic governing equations for the average concentration field can be deduced by homogenization. The necessary condition for this theory to be applied is the existence of a small parameter epsilon defined as the ratio of the scale of the pores and the scale of a sample, which can be distinguished in the heterogeneous medium. Transport processes with respect to different dominating phenomena, related to epsilon, have been examined. Using the analysis performed the condition has been specified when the homogenization is not possible, i.e. when it is impossible to find the rigorous macroscopic equivalent description.