METHOD OF MINING OF THICK STEEP COAL SEAMS Russian patent published in 2000 - IPC

FIELD: mining; applicable in underground mining of thick steep coal seams. SUBSTANCE: method includes coal mining by blocks; driving of vent, belt and sublevel drifts, raise on block flanks; drilling of deep holes in blocks; series hole blasting at a time with millisecond delay and discharge of broken coal through bunkers onto belt drift. Raises are also driven in middle part of blocks. Cross-cuts are driven from raises across the strike through full heights of blocks. Drilled from cross-cuts are deep horizontal and slightly inclined holes and also upward holes. Blasting of the first series of holes forms the clamping medium through entire thickness of seam: blasting of hole charges at level of sublevel and vent drifts in lower and upper parts of block; blasting of upward holes between cross-cuts in middle part of blocks, and breakage of coal block by series of secondary blasting of horizontal and slightly inclined holes in compressed medium. It is expediently to break block of strong coal by secondary series of blasting of upward holes in compressed medium. Claimed method provides for higher safety of mining due to absence of nonsupported space in drilling and charging of holes and blasting of hole charges at one step in compressed medium with absence of free space for accumulation and explosion of methane and coal dust. EFFECT: higher safety of mining operations, reduced labor input in preparation for mining and mining of coal mass. 2 cl, 6 dwg