Study of biohydrometallurgical technology used to recover gold from ore at a gold-recovery plant

Abstract

The article contains the results of the studies performed for the biochemical eхtraction modes for mineral raw materials using thionic bacteria Acidithiobacillusferrooxidans of a certain strain capable to oxidize sulfide minerals. A representative sample of mineral raw materials was taken, and its physical and chemical studies were performed. The optimal conditions to leach mineral raw materials with biochemical solvents based on various factors (temperature, S:W) were established. Modern physical and chemical methods of analysis were used during the study: X-ray fluorescence, X-ray phase, mineralogical, electron probe, chemical analyzes, IR methods to study the phase composition of ores and changes in the structure of minerals. The chemical composition of the ore sample quartered and crushed up to a size of -0.074 mm is as follows, wt. %: SiO2 - 60.11; Al2O3 6.2; Zn 0.016; Cu 0.10; Fe - 2.5; S 0.50; Au - 3.67 g/t and Ag - 3.2 g/t. This paper discusses various options for agitational leaching with acid pre-wash, bacterial dissection and oxidative decomposition of minerals using sodium hypochlorite. The results obtained showed that the most effective method to increase the gold recovery is to perform bacterial oxidation of ore using acidophilic bacteria At. Ferrooxidans preliminarily adapted to the material composition of the test sample, followed by treatment with sodium hypochlorite solution and cyanidation. Biohydrometallurgical ore processing provides high gold recovery (78.1%).

Studies of the rate of gold sorption by the AM-2B anionite from cyanide-alkaline solutions

“…Productive gold-containing solutions obtained from agitation leaching are sent for sorption extraction. Ion-exchange resins or activated carbons are used as sorbents in industrial practice [ [6], [7], [8], [9], [10], [11], [12]].…”

Study of the Finely-Dispersed Gold Recovery Parameters

“…One of the new and effective methods created based on physical impact on the flotation process that enables simultaneously achieving high recovery and selectivity of separation of finely dispersed components with an increased specific productivity of the apparatus, is the method developed at "IMB" JSC by a flotation column in a unit with an air aerator [11]- [17].…”