Effect of Moisture on the Methane Capacity of American Coals.
Joubert-JI; Grein-CT; Bienstock-D
Fuel 1974 Jul; 53(3):186-191
An investigation of methane sorption in bituminous coals ranging from low-volatile to high-volatile b has been carried out. Equilibrium sorption isotherms for dry and moist coal were measured at 30 deg. C and at pressures up to 60 atm. The natural oxygen content of a coal plays a major role in determining its methane capacity. Capacities of high-oxygen coals undergo a much greater reduction when saturated with moisture than do low-oxygen coals. Measurements of adsorbed-water saturation capacities clearly suggest that only adsorbed water affects the equilibrium capacity of a coal for methane; water present in excess of the adsorbed water has no effect on methane sorption. Excellent agreement has been found between the methane sorption data reported here and field measurements of methane emission from coal samples obtained during borehole drillings.
Fuel V. 53, No. 3, July 1974, PP. 186-191