In this work we consider the coupling between multiphase flow of binary-gas components (CH_4 and CO_2) and water in cleats coupled with the swelling of a poroelas-tic matrix leading to the closure of the cleats induced by the simultaneous methane desorption and carbon dioxide adsorption. Macroscopic governing equations are derived within the framework of the formal homogenization procedure where we upscale the anomalous behavior of the binary gas mixture in the nanopores. The adsorption isotherm is constructed rigorously by exploring the Thermodynamics of mhomoge-neous gases in nanopores. More precisely we consider spherical nanopores and apply the Density Functional Theory (DFT) to compute the gas density profiles incorporating both hard-sphere repulsion and Lennard-Jones attractive intermolecular interactions supplemented by a fluid-solid external potential. In addition we consider the mechanics of the matrix by computing the solvation force which induces the volume strain of the matrix. Finally a 2D reservoir simulation of methane production enhanced by CO_2 injection is presented to illustrate the potential of the multiscale model proposed herein.
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