Measurement of Coal Permeability Using Large Samples

A project being undertaken by a multidisciplined group at The University of Queensland is described. The project is examining fundamental aspects of coal seam methane and the scope of the various project sections is outlined. Coal bed methane flow into mine openings or drainage networks is strongly influenced by the seam property of permeability. Representative measurement of permeability must take into account aspect such ground stress, gas pressure, existence of water and structures within the coal. Laboratory measurements of this property have often in the past been undertaken on small diameter (\u3c25mm diameter) core. An approach to large sample permeability testing is described based on the use of HQ (61mm diameter) core tested in a permeability cell. This apparatus allows both axial and transverse core loading. Permeability is tested under varying gas pressures in either axial or transverse directions. Transverse testing allows permeability in flow paths parallel to coal piles to be established in core from holes drilled across the seam