An improved permeability model of coal for coalbed methane recovery and CO2 geosequestration

摘要: An alternative approach is proposed to develop an improved permeability model for coalbed methane (CBM) and CO2-enhanced CBM (ECBM) recovery, CO2 geosequestration in coal. This integrates the textural mechanical properties describe anisotropy of gas coal reservoirs. The accounts stress dependent deformation using a stress-strain correlation, which allows determination directional coals. correlation was developed by combining strain with sorption-induced any given direction. described general thermo-poro-elastic constitutive equations solid materials under isothermal conditions approximated treating swelling/shrinkage matrix equivalent thermal contraction/expansion materials. With strains, direction can be modeled based on theory rock hydraulics. In this study, tested both literature data experiments. experiments were carried out specially designed true tri-axial permeameter (TTSCP). results show that provides better predictions compared other conventional models. also gives reasonable agreement between predicted measured stress-strains permeabilities laboratory conditions.