METHOD FOR DEGASSING OF FOLLOWER-SEAM Russian patent published in 1997 - IPC

FIELD: mining industry. SUBSTANCE: this relates to working of gently inclined coal seams for preventing creation of local and in-seam accumulation of methane in zone behind stoping face of underground working near boundary of worked-out space. Method implies drilling of bore-holes in seam foot rocks towards stoping face beyond supporting pressure zone in direction of relieving zone, casing, cementation and hermetic sealing of bore-holes and connecting them to vacuum system. Determined preliminarily is relieving pitch, and then niches are formed, and distance between them is taken as equal to not less than relieving pitch of follower-seam. Determined graphically with taking account of bore-hole vacuum are parameters of drilling bore-holes in the form of cluster. Heads of bore-holes are grouped in niche beyond boundary of plastic deformation zone. Connection of bore-holes to vacuum system is performed prior to coming of stoping face to them. Gas sucking is started ahead of stoping face in section of length calculated according to formula and is continued behind stoping face in zone of receiving follower-seam to ensure catching of gas emitting from foot rocks by bore-holes. In working zone of section behind stoping face, rock is blasted with advancement of stoping face. EFFECT: higher efficiency. 6 dwg