Super-critical carbon dioxide flow behaviour in low rank coal: A meso-scale experimental study

Abstract

The carbon dioxide (CO2) adsorbed in coal seams during CO2-enhanced coal bed methane recovery (CO2-ECBM) causes substantial coal matrix alterations, resulting in significantly reduced flow performance. Many studies have been conducted to date on the effect of CO2 phase on coal mass permeability. However, the effect of coal rank on these permeability changes with CO2 phase has not yet been studied. Therefore, the main aim of this study is to investigate how the influence of CO2 phase condition on coal flow performance varies with rank. A series of tri-axial permeability tests was conducted using Australian brown coal samples for both CO2 and N2 under various confinements and injections at 35 ..