METHOD AND APPARATUS FOR RECOVERING GOLD FROM LOW-GRADE ORES Russian patent published in 1997 - IPC

FIELD: precious metal hydrometallurgy. SUBSTANCE: method consists in charging ore, percolation leaching of gold from ore charge with cyanide solution, sorption of gold, washing ore charge to isolate dissolved gold using removing gold from wash solutions, neutralization of leaching cakes, and their discharging. According to invention, ore charge is saturated with cyanide solution from below upward, separated, and subjected to passive cyanidation in air, whereas washing away dissolved gold is performed consecutively by preliminarily devoid of gold solution until gold concentration in productive solution attains 0.05-0.1 mg/l. Installation contains at least three percolation leaching block sections, reservoir for initial leaching solution, sorption unit, container for gold-free solution, and reservoir for neutralizing solution. Invention is distinguished by that percolation block sections are made in the form of dishes with, built in into bottom, perforated connecting pipes for introducing and withdrawing process solutions, each of them being connected with collector for feeding and draining solutions into pipeline of corresponding container. Between sorption unit and block sections, there is container to collect productive gold-containing solutions connected through percolation block sections and sorption unit with gold-free solution container into closed circuit. EFFECT: enhanced efficiency of gold recovery. 3 cl, 2 dwg