After several trials and errors, an acceptable procedure has been formulated for cutting, handling, preparing, and selecting coal core samples for laboratory tests. The unsteady-state method for relative permeability measurement has been found to provide satisfactory results when applied to whole core samples of coal. Furthermore, a novel nondestructive and simple laboratory technique has been developed to estimate the porosity and irreducible water saturation associated with the coal cleat network. In this paper, examples are presented using results obtained with coal core samples from the San Juan and Warrior Basin. Laboratory measured relative permeability curves, porosity, and irreducible water saturation of coal cleats have proven valuable in numerical simulation and other engineering studies of coalbed methane recovery.

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