METHOD OF PILLAR DESTRUCTION Russian patent published in 2009 - IPC E21C41/22 F42D3/04 

FIELD: mining.

SUBSTANCE: invention can be implemented at development of mineral deposits by method of explosion for destructing between-chamber and under-goaf pillars of ore deposits, and also for block caving under conditions of increased mine pressure. The method of destruction of pillars consists in drilling boreholes in the pillar and in placing charges of explosion material EM in them, in driving upward boreholes and in placing chamber charges of EM in them, in successive explosion with formation of system of opposite relieving cavities into two opposite surfaces of pillar exposure and in final destruction of the pillar by explosion of the chamber charges of EM. Coaxially with project contours of reliving cavities additional boreholes are drilled. The additional boreholes are arranged symmetrically to the lengthwise axis of the pillar, and charges of EM are placed into them. Initially the relieving cavities are formed on ends of the pillar, further other cavities are formed. Charges of EM in additional boreholes located on ends of the pillar are exploded after formation of the relieving cavities. Simultaneous explosion of chamber charges of EM and charges of EM left in additional boreholes is performed last of all.

EFFECT: upgraded quality of crushing increased safety of mining.

4 dwg, 1 ex