The effects of stress and fracturing on permeability of coal

Abstract This paper examines the changes in structure and permeability of coal under the stress conditions experienced around longwall faces. The effect of fracturing on permeability of coal is discussed, and the stress—permeability relationship for fractured coal is compared with that of non-fractured coal. An empirical relationship between stress and permeability for coal is derived from the experimental data which relates the stress—permeability behaviour of coal to its rank through the compressibility of the coal itself.