Method for in situ gas production from coal seams

摘要

Gas is produced and extracted from a coal deposit by drilling a row of supply wells in the deposit for receiving air or another combustion supporting gas, cutting horizontal inclined supply passages along the bottom of the deposit extending from the bottom end of the supply wells to a channel at the other end of the deposit perpendicular to and interconnecting the supply passages, igniting the coal face in the channel to create a combustion zone, maintaining combustion by continuously supplying air to the combustion zone via the supply wells and supply passages, and continuously removing gases produced by combustion via a central discharge passage extending along the deposit parallel to the supply passages and production wells drilled from the surface to the discharge passage in a row perpendicular to the row of supply wells.