METHOD FOR MINING DIAMOND-CARRYING KIMBERLITE PIPES Russian patent published in 1997 - IPC

FIELD: mining industry. SUBSTANCE: method relates to mining deposits of hard minerals, mainly to mining diamond-carrying kimberlite pipes by deep-water dredging. For this purpose in preparatory period, created beyond kimberlite pipe perimeter is counterfiltration curtain, ore body is exposed by excavation, ore body is marked into vertical concentric blocks, tailings storage is built, then lowered into water-filled excavated basin are elevator dredge and suction-tube dredge. Deep-water dredging is performed from top downwards by successive cutting vertical concentric ore blocks in direction from center of dredge basin towards its sides with gradual lowering of mining breast over central ore column down to design depth. Peripheral blocks are mined down to protective ore pillar left in zone of contact with embracing rock. Kimberlite pipe is worked by elevator dredge and suction-tube dredge on which mining machinery is installed according to technological system ensuring continuous cutting of ore mass over entire area of preset section of block with hydraulic cleaning of cutting face. Tailings are delivered into separately located store, cleaned water after settling of sludge is returned for repeated use in closed circulation system. To reduce volume of tailings store, sludge is preliminarily thickened and filtered. Filtrate is returned for repeated use and thickened tailings are delivered to store. Method can be used for mining large-capacity deep-lying (buried) placer deposits. It is safe and profitable and least disturbing to environment. EFFECT: high efficiency. 3 cl, 5 dwg