METHOD OF UNDERGROUND GASIFICATION OF FLAT AND INCLINED COAL BENCHES Russian patent published in 2010 - IPC E21B43/295 E21B43/30 

FIELD: mining.

SUBSTANCE: invention relates to mining, particularly to development of coal deposits by their gasification. Proposed method comprises drilling the wells, combustion face ignition and generator gas withdrawal. Vertical central well is drilled from the surface onto formation, other wells being drilled around it, at the distance of bench coal hydraulic fracturing radius. Oriented circular hydraulic bench fracturing is performed through central well to connect all wells, then combustion face ignition and blowdown are carried, while generator gas is withdrawn through the other wells. Nest row of wells is drilled within the limits of hydraulic fracturing radii as far as gasification proceeds to cause circular hydraulic fracturing through said wells and generator gas withdrawal, while previous row of wells is used for blowdown. Note here that wells used earlier for blowdown purposes are subjected to tamping.

EFFECT: reduced coal loses and coal bench exploitation intervals.

3 cl, 3 dwg, 1 ex