RU-2861647-C1 - METHOD FOR PROCESSING SULPHIDE-OXIDISED ORES WITH RECOVERY OF COPPER AND SILVER

RU2861647C1RU 2861647 C1RU2861647 C1RU 2861647C1RU-2861647-C1

Abstract

FIELD: mining industry. SUBSTANCE: invention relates to the extraction of copper and silver from sulphide-oxidised copper ores. The method includes crushing and staged grinding of the ore with intercycle collective flotation to recover a collective concentrate which is subjected to atmospheric sulphuric acid leaching, countercurrent washing. The obtained pulp is separated into liquid and solid phases. The solid phase is sent after neutralisation to attrition scrubbing and subsequent extraction of copper and silver by flotation to recover a copper flotation concentrate in which silver-containing minerals are associated with copper sulphide minerals. The liquid phase is sent to the stage of copper precipitation with a precipitant - sodium hydrosulphide or sodium sulphide - to obtain a copper sulphide precipitate. Wherein in the process of copper sulphide precipitation, the degree of copper precipitation is controlled by regulating the precipitant feed mode, avoiding complete quantitative precipitation of copper to prevent excessive release of hydrogen sulphide. EFFECT: high recovery of copper and silver into copper flotation concentrate, production of high-quality copper sulphide from the oxidised fraction with a copper content of at least 40%, minimal release of hydrogen sulphide gas. 3 cl, 4 dwg, 1 tbl, 1 ex

Inventors

Iashchuk Aleksei Alekseevich
Cherkasov Valerii Iurevich
Naidanov Oleg Dorzhievich
Ezhurov Ruslan Olegovich

Dates

Publication Date: 20260506
Application Date: 20250514

Claims (3)

1. A method for processing sulfide-oxidized copper ores to obtain copper and silver, comprising crushing and subsequent stage-by-stage grinding of the ore with inter-cycle collective flotation of sulfide and oxidized copper minerals from the crushed ore with the separation of a collective concentrate, its atmospheric sulfuric acid leaching with mixing with an aqueous solution of sulfuric acid, counter-current washing, separation of the resulting pulp into liquid and solid phases, wherein the solid phase - leaching cake, is sent after neutralization to attrition and subsequent extraction of copper and silver from it by flotation to separate a copper flotation concentrate in which silver-containing minerals are associated with copper sulfide minerals, and the liquid phase - a productive copper-containing solution, is sent to the copper precipitation stage, characterized in that the copper precipitation is carried out by a precipitating agent, which is sodium hydrosulfide or sodium sulfide, with the production of a copper sulfide precipitate, whereby the copper sulfide obtained by precipitation is an independent product, or it is mixed with copper flotation concentrate, and in the process of copper sulfide precipitation, the degree of copper precipitation is controlled by controlling the feeding mode of the precipitant, not allowing complete quantitative precipitation of copper in order to prevent excessive release of hydrogen sulfide due to a side reaction of the precipitant with sulfuric acid.
2. The method according to paragraph 1, characterized in that the precipitant is fed to the copper sulfide precipitation process with an average consumption of sodium hydrosulfide or sodium sulfide of 0.8-1.38 g/g of copper contained in the solution.
3. The method according to paragraph 1, characterized in that the control of the precipitant feed mode is carried out by means of an automated process control system, in which, based on the flow rate of the productive copper-containing solution and the copper content in it, the amount of copper supplied with the solution and the required ratio of the precipitant supplied are calculated, while the concentration of hydrogen sulfide is constantly monitored in the apparatuses used and around the working area of the copper sulfide precipitation process, and if a predetermined hydrogen sulfide concentration threshold is exceeded, the feed of the precipitant is blocked, preventing the occurrence of a dangerous concentration of gas.

Description

The invention relates to non-ferrous metallurgy, in particular to copper and silver metallurgy, namely to methods for extracting metals from sulfide-oxidized copper ores. A method for extracting copper by leaching copper concentrates is known (Patent of the Russian Federation No. 2373298). The invention relates to hydrometallurgy, specifically to the leaching of copper from copper sulfide-containing concentrates such as chalcopyrite. The process involves using pyrite as a catalyst for the reduction of ferric iron to avoid passivation of the chalcopyrite surface. The process is carried out under conditions that substantially prevent pyrite oxidation, for example, by maintaining the working potential of the solution at an appropriate level. The mass ratio of chalcopyrite to pyrite ranges from less than 3:1 to 1:20. Leaching is carried out in an acidic sulfate medium and may include oxidation with an oxygen-containing gas. The leached copper is then recovered, for example, by solvent extraction and electrowinning. A method for extracting copper from mixed and oxidized ores (RU Patent 2337161) is known using tank leaching. Prior to leaching, the ore is crushed and ground to a particle size of 60-70%, no more than 3.0 mm. Leaching of the ore is carried out in tanks with stirring for 60-120 minutes using a sulfuric acid solution with an initial concentration of 10-40 g/L and a solids content of 50-70%. During the first 40 minutes of leaching, the sulfuric acid concentration is maintained at at least 10 g/L. After leaching is complete, the solid and liquid phases are separated, and copper is extracted from the liquid leaching phase. Copper is extracted from the liquid phase by solvent extraction followed by electrowinning. A method for precipitating non-ferrous metals (Author's Certificate No. 1207152) from acidic solutions is also known, which includes treating them with a solution of sulfur in calcium hydroxide, wherein the treatment is carried out together with alkali metal sulfides with a mass ratio of sulfide sulfur in alkali metal sulfides and a solution of sulfur in calcium hydroxide and calcium in calcium hydroxide of 1: 0.1 - 1.0, respectively. A method for precipitating non-ferrous metals is also known (Author's Certificate No. 1129258), for example, arsenic, copper and zinc from acidic solutions by treatment with alkali metal sulfides, wherein the treatment is carried out in the presence of thiosulfate ion at a content of 0.5 - 2.0 g / l, and sodium sulfohydrate is used as the alkali metal sulfide. A method for processing oxidized copper ores with copper extraction is known (RU Patent No. 2179589). In this patent, the method includes crushing and grinding the feedstock to a fraction size exceeding the required fraction size for flotation, leaching followed by separation of the liquid and solid phases of the product with simultaneous washing with a portion of the extraction raffinate and water, after which the solid phase of the product is further crushed and flotation is carried out, and the liquid phase is subjected to extraction with the separation of the raffinate and a copper-containing extractant solution, wherein the raffinate is repeatedly used in leaching and washing. The copper is re-extracted from the copper-containing extractant solution, and the regenerated extractant is used in extraction, and the pure copper-containing solution is subjected to electrowinning, after which the spent electrolyte is used in re-extraction, wherein the extraction is carried out by contacting the copper-containing solution with an organic cation-exchange extractant. A method for processing sulfide-oxidized copper ores with the extraction of copper and silver is also known (Patent of the Russian Federation No. 2604279). In this method, before feeding the bulk concentrate obtained from sulfide-oxidized copper ore to acid leaching, a staged bulk flotation process is performed with the addition of sodium sulfide. Before the first stage of bulk flotation, the ore is crushed to 140-190 micron particles, and the tailings are sent to the second stage of bulk flotation. Before the second stage, the tailings are crushed to 60-90 micron particles. Sodium sulfide is added at predetermined intervals during the bulk flotation stages. Before copper and silver are extracted by flotation from the concentrate leaching cake, the cake is crushed to 20-30 micron particles. The disadvantage of this method is the complexity of the technological process due to the need to use expensive reagents at the copper extraction stage to obtain a copper cathode. The technical objective is to develop a method for processing sulfide-oxidized copper ores to produce high-quality copper flotation concentrate and copper sulfide as a standalone product. Ensuring process safety. The technical result is a high extraction of copper and silver into copper flotation concentrate, as well as the production of high-quality copper sulfide (copper concentrate) fr