Effect of Coal Rank on CO2 Adsorption Induced Coal Matrix Swelling with Different CO2 Properties and Reservoir Depths

Abstract

Although the greater adsorption potential of carbon dioxide (CO2) in coal is an appealing fact in relation to the long-term safe storage of CO2 in coal seams, the resulting coal structure modification, particularly through coal matrix swelling, adds several uncertainties to the process. To date, many studies have been initiated, particularly on the effects of injecting CO2 and reservoir properties on this swelling process and the associated reservoir permeability depletion. These influences are largely dependent on the maturity of the coal mass and its structure, including the cleat system. However, minor attention has been given to date to the effect of coal rank on CO2 adsorption-induced c..