Multicomponent Gas Counter-Diffusion In Coal (2006–2008)
This project is directed at understanding and quantifying multicomponent gas diffusion in coal. For enhanced coalbed methane (ECBM) recovery, the diffusion of the CH4, the enhancement fluid, and other gases in the coal pores, are opposed and cause mutual interference. This effect is neglected or oversimplified in current coal-gas reservoir simulators. This counter-diffusion depends on coal properties including pore morphology and free water, as well as local conditions such as pressure, species, concentration and stress. Through experiments, informed by theory, this project will develop a counter-diffusion model for CH4, CO2, N2 in wet coal for inclusion in CBM reservoir simulators.