METHOD FOR UNDERGROUND MINING OF COMPLEX COPPER-GOLD DEPOSITS WITH ACTIVATION LEACHING Russian patent published in 2022 - IPC E21C41/22 E21B43/28 

FIELD: mining industry.

SUBSTANCE: invention relates to the mining industry and can be used in the underground development of complex copper and gold deposits. The method for underground mining with activation leaching involves placing the main explosive charges in twinned holes. In addition to explosive charges, thin-walled pipes with reagents are placed in wells of increased diameter and twinned holes, and explosive charges in wells of increased diameter are detonated with an increased deceleration interval relative to adjacent twinned holes. Successively, the blasted ore is impregnated with a weakly concentrated electroactivated oxidizing solution of sulfuric acid and voltage is applied to electrodes placed in porous casing pipes with a value that ensures the implementation of the electrolysis process in the initial solution of reagents inside the porous casing pipes and electrodiffusion processes initiated by electrolysis of ions and molecules of electrolysis gases through porous casing pipes into the volume of the blasted ore to soften the joints. Sulfuric acid is produces directly in the blasted ore and the oxidation process of sulfide and sulfosolic minerals containing copper and related valuable components soluble in sulfuric acid is intensified. The voltage is switched off at the electrodes, the exploded ore is irrigated with initially oxygenated water and sent through a pipeline to the surface. The barren solutions are oxygenated and fed to the next irrigation cycle until the main part of copper and related valuable components soluble in sulfuric acid are extracted from the blasted ore. A concentrated solution of sodium chloride is supplied, which is conditioned by pH with hydrochloric or sulfuric acid and subjected to electrolysis. The resulting alkaline solution of sodium hypochlorite as a result of barodiffusion enters the acidic environment surrounding the exploded ore, as a result of which, when the pH rises to the level of 6.5-7.3, a complexing agent for gold is formed: hypochlorous acid. After the stage of chloride electrochemical leaching of gold, the voltage on the electrodes is turned off, and the exploded ore is irrigated with an active chloride-hypochlorite solution obtained in an electrochemical reactor.

EFFECT: method provides an increase in the technological efficiency of mineral extraction, process maintenance productivity, production profitability and environmental safety.

1 cl, 2 dwg