METHOD FOR KIMBERLITE PIPE DEVELOPMENT UNDER DIFFICULT HYDROGEOLOGICAL CONDITIONS Russian patent published in 2005 - IPC

FIELD: mining industry, particularly crystal-saving diamond mining when developing permafrost kimberlites under difficult hydrogeological conditions of permafrost zones.

SUBSTANCE: method involves loosening rock, converting rock into pulp and conveying pulp through pulp line by dredger. Before subpermafrost zone opening hole having large diameter is driven from pit bottom for the full depth of field to be developed and inclined borehole is built. The borehole is connected to the hole in point located at said depth and then high-pressure subpermafrost brine is pumped into the pit. Airlift dredger is arranged on water body surface, ripper-dozer provided with all-purpose boring bit is lowered on pit bottom. Loosening of kimberlites weakened by brine is performed by ripper-dozer along helical cuts. Fine ore cuttings are conveyed by means of airlift through pulp line to ore mill. Coarse ore cuttings are moved to ground surface to ore storage through hole, caisson drift and inclined borehole provided with skip hoist. Kimberlite pipe development below pit bottom is performed at right angles of faces depreciation without performing overburden operations.

EFFECT: increased gem diamond yield and resource saving due to deep horizons with opened worked-out space development without overburden operations and improved ecological safety.

4 dwg, 1 ex, 1 tbl