Flotation method for gold ore

Abstract

The invention belongs to the technical field of flotation, and particularly relates to a flotation method for gold ore. According to the method, coarse-grain gold minerals which are easy to reselect and difficult to float are subjected to ore grinding stage by stage on the premise of avoiding over-grinding, and selective dissociation of gold (containing) minerals and gangue minerals is facilitated; gold minerals are separated and recovered in advance under the coarse grain condition through the technology of spiral chute reselection and table reselection, the situation that the gold minerals are lost in the mineral separation process due to fine grinding argillization is avoided, and meanwhile, the flotation reagent consumption is reduced; a reasonable flotation process is designed for remaining fine-grain gold (containing) minerals in reselection tailings obtained through the technology of spiral chute reselection and table reselection, gold-containing sulfide and oxide which are prone to floating are separated preferentially, scavenging tailings are independently subjected to re-flotation, interference of target minerals difficult to float on useful minerals easy to float is reduced, and efficient enrichment of the gold (containing) minerals and pre-discarding of the gangue minerals are realized.

Description

technical field [0001] The invention belongs to the technical field of flotation, in particular to a gold ore flotation method. Background technique [0002] Quartz vein type gold deposit refers to a type of ore deposit formed by metasomatism and precipitation of hot water solution in vein shape. The main useful minerals in the ore are native gold and a small amount of tellurite. The main metal minerals are pyrite, Chalcopyrite and galena, the main non-metallic minerals are quartz, feldspar, a small amount of chlorite and calcite. The embedded particle size of natural gold in the ore ranges from 0.2 to 300 μm, generally 0.2 to 30 μm. Except for a small amount of natural gold particles that are relatively coarse, the embedded particle size of most gold minerals is fine, and most of them are dispersed in yellow gold. Inside or in crevices of minerals such as iron ore, galena, quartz, limonite or hematite. Altered rock type gold deposit is a kind of hydrothermal gold deposit,...

AI Technical Summary

Problems solved by technology

Both quartz vein type gold deposits and altered rock type gold deposits belong to hydrothermal gold deposits. The minerals in the ore have complex intergenerational relationships and common mineralization alterations. It is difficult to sort through conventional beneficiation processes.

[0003] The existing gold ore beneficiation process is to finely grind the crushed raw ore to a particle size of 0.074mm, accounting for 85wt.%. All of them enter the cyanidation process for leaching, and all ores are transformed into highly toxic cyanide slag. The Au content in the slag is mostly in the More than 0.3g / t, the tailings cannot be thrown directly; at the same time, this process also has the problems of difficult backfilling of tailings and high consumption of leaching agent, and the recovery rate of gold concentrate is low

There is another gold ore production process, which adopts ore dressing technology to realize the pre-tailing and enrichment of ore, such as gravity separation first, which is used for the initial enrichment of gold, and then further improves the grade of gold in the concentrate through flotation, but For quartz vein-type gold deposits or altered rock-type gold deposits, except for a small part of the target minerals are coarse-grained natural gold, most of the particle size is fine (<30μm) and relatively scattered, and the pre-separation process of ores faces many challenges. The problem is that on the one hand (containing) gold minerals have large differences in particle size, and the coarse-grained natural gold is easily over-grinded and lost in the tailings during the ore dissociation process; on the other hand, due to limonization, oxidation, etc. The floatability of gold sulfide is poor, which is not conducive to flotation recovery

The tailings of the existing gold mines are of high grade and cannot be directly discarded, and the recovery rate of gold concentrate is low

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