Method for combined concentration and metallurgical processing of copper-cobalt ore with high calcium and magnesium content

Abstract

FIELD: hydrometallurgy.SUBSTANCE: proposed invention relates to a method for the combined concentration and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium. A method for the combined concentration and metallurgical processing of copper-cobalt ore with a high calcium and magnesium content, in which the ore with a high calcium and magnesium content comprises MgO from 8 to 15 wt.% and CaO from 9 to 16 wt.%, includes the step S1: adding water to the high calcium and magnesium copper-cobalt ore to obtain an ore pulp, adding an environment regulator, a first collector and a first frother to the ore pulp for the first flotation to obtain a roughing copper-cobalt sulphide concentrate and roughing copper-cobalt sulphide tailings, the step S2: adding a reducing agent to the roughing copper-cobalt sulphide concentrate for calcination to obtain a calcined residue and an off-gas, the step S3: adding water and sulfuric acid to the calcined residue and leaching at atmospheric pressure, and then separating the solid and liquid materials to obtain a first leach product and a first leaching residue, the step S4: adding a sulfonating agent to the roughing copper-cobalt sulphide tailings for sulfonation, and then adding the second collector, a second frother and a gangue inhibitor for the second flotation to obtain a roughing copper-cobalt oxide concentrate and roughing copper-cobalt oxide tailings, the step S5: performing magnetic separation of the roughing copper-cobalt oxide tailings to obtain a magnetically separated cobalt oxide concentrate and magnetically separated cobalt oxide tailings, and the step S6: mixing the first leaching residue, the roughing copper-cobalt oxide concentrate and the magnetically separated cobalt oxide concentrate, adding water and sulfuric acid for oxidative leaching under elevated pressure, and then separating solid and liquid materials to obtain a second leach product and a second leaching residue.EFFECT: increase in the extraction of copper and cobalt.10 cl, 2 dwg, 1 tbl, 18 ex

Description

Cross-reference to related applications

[0001] This application claims the priority of Chinese Patent Application No. 202510332662.7, filed on March 20, 2025, the entire contents of which are incorporated herein by reference.Field of invention

[0002] The present invention relates to the technical field of hydrometallurgy, and more particularly to a method for combined enrichment and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium. Prior art of the present invention

[0003] High calcium-magnesium copper-cobalt ore is an ore with an oxidation state of 10 to 90% and a calcium oxide and magnesium oxide content in gangue minerals close to or exceeding 10%. High calcium-magnesium copper-cobalt ore, including ore occurring in sandstone, is characterized by a high degree of ore oxidation and a high calcium and magnesium content.The sandstone-hosted copper-cobalt ore with a high calcium and magnesium content mainly contains chalcocite, bornite, covellite and the like minerals in the form of copper sulfide ore, malachite, siliceous malachite, cuprite and the like minerals in the form of copper oxide ore, copper-cobalt sulfide ore (which is also referred to as carrolite) and the like minerals in the form of cobalt sulfide ore, cobalt-bearing dolomite, copper-cobalt plagioclase ore (which is also referred to as kolvesite) and the like minerals in the form of cobalt oxide ore, and the gangue minerals are mainly siltstone, quartz, dolomite and the like minerals. Copper in the high calcium and magnesium copper-cobalt ore is mainly present in the form of copper sulfide, and cobalt is mainly present in the form of cobalt oxide ore, and the composition of the high calcium and magnesium copper-cobalt ore is relatively complex.Due to the relatively high copper and cobalt sulfide content of the ore, achieving optimal leaching rates with direct leaching proves challenging. Furthermore, since the gangue contains minerals such as dolomite with high calcium and magnesium content, direct acid leaching results in high acid consumption, which increases production costs.

[0004] CN Patent No. 114054201A discloses a method for beneficiating mixed copper-cobalt ore with a high content of magnesium sulfide and oxide. Sulfide concentrate and roughing oxide concentrate are obtained through stage flotation, and most of the calcium-magnesium minerals in the gangue are simultaneously separated. The resulting roughing copper-cobalt oxide concentrate is subsequently subjected to a hydrometallurgical copper recovery process, which reduces the amount of ore processed and the acid consumption in wet leaching, thereby conserving resources and reducing costs. However, only the roughing copper-cobalt oxide concentrate obtained by flotation is processed, with a total copper recovery rate of only 85.12% and a total cobalt recovery rate of only 73.93%, with the copper and cobalt recovery rates being relatively low.Patent CN 114950712 A discloses a combined processing method for the complete recovery of copper and cobalt. Copper-cobalt ore and individual cobalt ore are subjected to flotation and magnetic separation, resulting in copper sulfide concentrate, copper oxide concentrate, cobalt concentrate after flotation, and cobalt concentrate after magnetic separation, respectively. The copper sulfide concentrate is subjected to wet leaching after roasting, and the copper oxide concentrate, cobalt concentrate after flotation, and cobalt concentrate after magnetic separation are directly subjected to wet leaching. However, the residue after wet leaching of the copper sulfide concentrate is not further recovered, and atmospheric pressure leaching is used for wet leaching. Due to the presence of sulfur, the leaching rates of copper and cobalt remain low.

[0005] Currently, there are three main processing routes for copper-cobalt ores with high calcium and magnesium content: pyrometallurgy, acid leaching, and flotation. Pyrometallurgical processing mainly involves matte smelting in a copper matte converter (also known as the converter-blown matte smelting process), which has problems such as high capital investment, increased smelting costs, significant environmental impact, and high copper content in the residue. When acid leaching is used to process copper-cobalt ores with high calcium and magnesium content, there are disadvantages such as excessive acid consumption and high production costs. At the same time, a large amount of difficult-to-leach copper-cobalt sulfide ore remains in the tailings, which hinders the complete recovery of copper and cobalt.The flotation method is mainly a "copper-cobalt bulk flotation" beneficiation process, but there are problems such as low recovery rate of oxide copper-cobalt ore and high content of calcium and magnesium in the concentrate, and the concentrate with high content of calcium and magnesium will reduce the quality of the concentrate and increase the difficulty in subsequent metallurgical processes. Brief disclosure of the present invention.

[0006] The object of the present invention is to provide a method for the combined enrichment and metallurgical processing of copper-cobalt ore with a high calcium and magnesium content, so as to solve the problems of the prior art, such as high production costs and low recovery rates of copper and cobalt as a result of processing copper-cobalt ore with a high calcium and magnesium content.

[0007] In order to solve the above-mentioned problem, according to an aspect of the embodiments of the present invention, a method for the combined beneficiation and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium is provided. The method comprises steps S1-S6. In step S1, water is added to the copper-cobalt ore with a high content of calcium and magnesium to obtain an ore pulp, a first collector is added to the ore pulp for the first flotation to obtain a copper-cobalt sulfide roughing concentrate and copper-cobalt sulfide roughing tailings. In step S2, a reducing agent is added to the copper-cobalt sulfide roughing concentrate for calcination to obtain a calcined residue and an off-gas.In stage S3, water and sulfuric acid are added to the roasted residue, and atmospheric leaching is performed, followed by solid-liquid separation to produce a first leach product and a first leaching residue. In stage S4, a sulfonating agent is added to the copper-cobalt sulfide tailings from roughing for sulfonation, and then a second collector is added for a second flotation to produce copper-cobalt oxide concentrate from roughing and copper-cobalt oxide tailings from roughing. In stage S5, magnetic separation of the copper-cobalt oxide tailings from roughing is performed to produce cobalt oxide concentrate from magnetic separation and cobalt oxide tailings from magnetic separation.In the S6 step, the first leaching residue, the rough processing copper-cobalt oxide concentrate and the magnetic separation cobalt oxide concentrate are mixed, water and sulfuric acid are added for oxidative leaching under high pressure, and then solid-liquid separation is carried out to obtain the second leaching product and the second leaching residue.

[0008] According to some embodiments, in step S1, the solids content of the ore pulp is from 20 to 40%. According to some embodiments, step S1 further comprises grinding copper-cobalt ore with a high calcium and magnesium content to obtain ground ore and adding water to the ground ore to obtain ore pulp. From 65 to 85 wt.% of the ground ore has a particle size of no more than 0.074 mm.

[0009] According to some embodiments, in step S1, the first collector comprises one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate and O-isopropyl ethyl thiocarbamate, which are added in an amount of from 50 to 300 g / t, and / or the first flotation is carried out for a period of time of from 2 to 10 minutes, wherein the mixing duration is from 1 to 5 minutes. According to some embodiments, a regulator, a first collector and a first frother are sequentially added to the ore pulp for the first flotation. The regulator contains one or more substances selected from the following: calcium oxide, calcium hydroxide and calcium carbonate, in order to adjust the pH of the ore pulp from 7 to 10, and the first frother contains pinitol oil, which are added in an amount of from 20 to 50 g / t.

[0010] According to some embodiments, in step S2, the reducing agent comprises one or more substances selected from the following: sodium carbonate, sodium sulfate, or sodium chloride; and / or the weight ratio of the copper-cobalt sulfide roughing concentrate and the reducing agent is from 1:0.2 to 1:0.5; and / or the calcination is carried out at a temperature of from 400 to 600°C for a period of time of from 2 to 4 hours. According to some embodiments, step S2 further comprises adding water to the off-gas to produce sulfuric acid and returning the sulfuric acid to atmospheric pressure leaching and / or elevated pressure oxidative leaching.

[0011] According to some embodiments, in step S3, the acid-to-ore ratio for leaching at atmospheric pressure is from 180 to 280 kg / t, the liquid-to-solid ratio is from 3:1 to 5:1, and the stirring speed is from 300 to 600 rpm, and / or leaching at atmospheric pressure is carried out at a temperature of from 25 to 90°C for a period of time of from 60 to 240 minutes, and the pH value of the solution at the end point of leaching is from 0.8 to 2.5.

[0012] According to some embodiments, in step S4, the sulfonating agent comprises sodium sulfide and / or sodium hydrosulfide, which are added in an amount of from 1000 to 3000 g / t, and / or the second collector comprises one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate, potassium amyl xanthate and sodium amyl xanthate, which are added in an amount of from 500 to 2000 g / t, and / or sulfonation is carried out for a period of time of from 30 to 80 minutes, and / or the second flotation is carried out for a period of time of from 2 to 10 minutes, wherein the mixing duration is from 2 to 6 minutes. According to some embodiments, the sulfonating agent is added to the copper-cobalt sulfide roughing tailings for sulfonation, and then the second collector, the second frother and the inhibitor are sequentially added for the second flotation.The second foaming agent contains pinitol oil, which is added in an amount of 20 to 50 g / t, and the inhibitor contains sodium hexametaphosphate and / or carboxymethylcellulose, which are added in an amount of 40 to 200 g / t.

[0013] According to some embodiments, in step S5, the intensity of the background magnetic field for magnetic separation is 0.3 to 2.0 T. According to some embodiments, the magnetic separation includes preliminary magnetic separation, purification magnetic separation and final magnetic separation, which are carried out sequentially.

[0014] According to some embodiments, in step S6, the acid-to-ore ratio for the high-pressure oxidative leaching is 180 to 220 kg / t, the liquid-to-solid ratio is 6:1 to 10:1, and the stirring speed is 600 to 800 rpm; and / or the high-pressure oxidative leaching is carried out at a temperature of 160 to 220°C for 0.8 to 2 hours, the oxygen partial pressure is 0.3 to 0.8 MPa, and the pH value of the solution at the end point of leaching is 1.2 to 2.0.

[0015] According to some embodiments, in step S6, the first leaching residue is subjected to third flotation to obtain a copper-cobalt sulfide enriched leaching residue. The copper-cobalt sulfide enriched leaching residue, the copper-cobalt oxide concentrate from rough processing, and the cobalt oxide concentrate from magnetic separation are mixed, and water and sulfuric acid are added for oxidative leaching under elevated pressure.

[0016] According to some embodiments, the copper-cobalt ore with a high calcium and magnesium content has a Cu content of 0.5 to 5 wt.%, a Co content of 0.1 to 1 wt.%, a MgO content of 8 to 15 wt.%, a CaO content of 9 to 16 wt.%, and an S content of 0.2 to 0.6 wt.%.

[0017] By applying the technical solution proposed in accordance with the embodiment of the present invention, a method of sequential sulfide and oxide flotation and beneficiation with combined atmospheric pressure leaching and elevated pressure oxidative leaching is used to effectively leach copper and cobalt from copper-cobalt ore with high calcium and magnesium content. The flotation and magnetic separation processes result in the production of copper-cobalt sulfide concentrate of rough processing, copper-cobalt oxide concentrate of rough processing, and cobalt concentrate after magnetic separation.The copper-cobalt sulfide concentrate is then roasted to produce a roasted residue and off-gas, and the roasted residue is leached at atmospheric pressure to produce a copper-cobalt leachate and a leaching residue containing unleached copper-cobalt complex sulfide. Finally, the leaching residue, copper-cobalt oxide concentrate, and cobalt concentrate after magnetic separation are subjected to oxidative leaching at elevated pressure to produce a copper-cobalt leachate with a high metal recovery rate. The method proposed in accordance with embodiments of the present invention is characterized by simplicity, relatively low cost, and a relatively high copper and cobalt recovery rate. Brief Description of the Figures.

[0018] The accompanying figures in the description, which form a part of the present invention, are intended to provide a better understanding of the present invention, and the illustrative embodiments of the present invention and the corresponding descriptions serve to explain the present invention, but do not constitute unreasonable limitations of the present invention.

[0019] Fig. 1 illustrates a process flow chart representing a method for combined enrichment and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium according to Example 1 of the present invention.

[0020] Fig. 2 illustrates a process flow chart representing a method for combined enrichment and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium according to Example 2 of the present invention. Detailed disclosure of the present invention

[0021] It should be noted that, without contradiction, the embodiments and features in the embodiments of the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying figures and with the presentation of embodiments.

[0022] Terminological Explanation

[0023] Added reagent amount: The mass ratio of the reagent used (in grams) to the ore to be processed (in tons).

[0024] Acid to Ore Ratio: The mass ratio of liquid acid (in kilograms) used during the leaching process and the material to be leached (in tons).

[0025] Liquid to solid ratio: the mass ratio of liquid to solid materials in the ore pulp during the leaching process.

[0026] As described in the section "Prior Art of the Present Invention," the prior art literature describes problems of high production costs and low copper and cobalt recovery rates in the process of processing copper-cobalt ore with a high content of calcium and magnesium. In order to solve the above-mentioned problems, according to an embodiment of the present invention, a method for the combined beneficiation and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium is provided. The method includes steps S1-S6. In step S1, water is added to the copper-cobalt ore with a high content of calcium and magnesium to obtain an ore pulp, and a first collector is added to the ore pulp for the first flotation to obtain a copper-cobalt sulfide roughing concentrate and copper-cobalt sulfide roughing tailings.In stage S2, a reducing agent is added to the copper-cobalt sulfide roughing concentrate for calcination, producing a calcined residue and off-gas. In stage S3, water and sulfuric acid are added to the calcined residue, and atmospheric pressure leaching is performed, followed by solid-liquid separation to produce a primary leachate and a primary leaching residue. In stage S4, a sulfonating agent is added to the copper-cobalt sulfide roughing tailings for sulfonation, and then a second collector is added for a second flotation to produce copper-cobalt oxide roughing concentrate and copper-cobalt oxide roughing tailings.At stage S5, magnetic separation of the copper-cobalt oxide tailings from roughing is performed, yielding a cobalt oxide concentrate from magnetic separation and cobalt oxide tailings from magnetic separation. At stage S6, the first leaching residue, copper-cobalt oxide concentrate from roughing, and cobalt oxide concentrate from magnetic separation are mixed, water and sulfuric acid are added for oxidative leaching at elevated pressure, and then solid-liquid separation is performed, yielding a second leach product and a second leaching residue.

[0027] Prior art literature describes that the processing of copper-cobalt ore with high calcium and magnesium content typically involves a combined enrichment and metallurgical processing method involving multi-stage flotation. This multi-stage flotation can lead to significant losses of metallic elements due to reduced metal recovery rates.In order to process copper-cobalt ore with a high content of calcium and magnesium, according to an embodiment of the present invention, a method of sequential sulfide and oxide flotation and enrichment is used, in which combined leaching at atmospheric pressure and oxidative leaching at elevated pressure are carried out to effectively leach copper and cobalt, and only a rough separation is carried out, in which copper-cobalt sulfide concentrate, copper-cobalt oxide concentrate and cobalt concentrate are obtained, the enrichment process is simplified and metal losses are reduced.

[0028] Specifically, water is added to copper-cobalt ore containing high calcium and magnesium content to form an ore slurry, and then a primary collector is added to the ore slurry for primary flotation. The collector can chemically adsorb on the surfaces of copper sulfide and cobalt sulfide-containing minerals, imparting hydrophobicity. The copper-cobalt sulfide ore is adsorbed on pre-selection bubbles and subjected to flotation to produce copper-cobalt sulfide roughing concentrate and copper-cobalt sulfide roughing tailings, which are then subjected to separate processing.

[0029] Next, a reducing agent is added to the copper-cobalt sulfide concentrate from the roughing stage for sulfonation during the roasting process. During this process, the reducing agent converts the metal sulfides in the copper-cobalt sulfide concentrate from the roughing stage into soluble salts that are more readily dissolved in the acidic leachate, thereby improving the efficiency of metal leaching. Furthermore, the reducing agent reduces the resulting sulfur dioxide to sulfates such as copper sulfate and cobalt sulfate, thereby reducing sulfur dioxide emissions and achieving sulfur fixation. Water and sulfuric acid are added to the resulting roasted residue for leaching at atmospheric pressure.According to the principle of acid leaching, soluble copper and cobalt compounds obtained from the roasted residue are dissolved in the solution through a chemical reaction, and the copper and cobalt are pre-extracted from the copper-cobalt sulfide concentrate from the roughing process. After separation of the solid and liquid materials, the primary leach product and primary leach residue are obtained. Due to the relatively small volume of the primary leach residue, the volume to be processed during subsequent processes can be significantly reduced.It should be noted that since the roasted residue of the copper-cobalt sulfide concentrate from rough processing contains unoxidized sulfides that cannot be recovered during leaching at atmospheric pressure, and if the unoxidized sulfides are directly sent to a tailings storage tank, this may cause losses of copper and cobalt, according to an embodiment of the present invention, the unoxidized sulfides are then sent to oxidative leaching at elevated pressure for secondary recovery with increased degrees of copper and cobalt recovery.

[0030] A sulfonating agent is added to copper-cobalt sulfide roughing tailings for sulfonation, and this sulfonating agent can convert calcium and magnesium ions into insoluble sulfides. A second collector is then added for secondary flotation. The second collector can selectively bind to copper-cobalt minerals to remove the bulk of calcium- and magnesium-containing, acid-consuming gangue from the copper-cobalt sulfide roughing tailings and remove carbonate minerals such as dolomite, thereby reducing the adverse effects of these minerals on subsequent leaching processes. The resulting products are copper-cobalt oxide roughing concentrate and copper-cobalt oxide roughing tailings. Sulfonation and secondary flotation can significantly reduce acid consumption during leaching, reducing production costs and increasing economic efficiency.The copper-cobalt oxide concentrate from the roughing process is then sent directly to high-pressure oxidative leaching without further purification, significantly reducing copper and cobalt losses. After high-pressure oxidative leaching, copper and cobalt recovery rates are high, while acid consumption is low.

[0031] Copper-cobalt oxide tailings from roughing operations retain a small amount of cobalt, but direct leaching of the cobalt is difficult because it is encapsulated in limonite. Therefore, copper-cobalt oxide tailings from roughing operations are sent for magnetic separation. Due to the different magnetic properties of limonite and cobalt, a strong magnetic field attracts magnetic substances such as limonite, while non-magnetic substances such as cobalt are repelled. This results in the recovery of a small amount of cobalt from the tailings, producing cobalt oxide concentrate after magnetic separation and cobalt oxide tailings after magnetic separation.Finally, the resulting cobalt oxide concentrate is sent to high-pressure oxidative leaching after magnetic separation, thus achieving a relatively high total recovery of copper and cobalt.

[0032] Compared with atmospheric pressure leaching, according to the present invention, the first leaching residue, the copper-cobalt oxide concentrate from rough processing, and the cobalt oxide concentrate from magnetic separation are mixed to form a mixture. This mixture is added to an autoclave along with water and sulfuric acid, and oxygen is simultaneously introduced for oxidative leaching at elevated pressure. During this process, oxygen can be used as a strong oxidizing agent instead of sulfuric acid, thereby reducing the required amount of sulfuric acid. The solubility of oxygen can increase at high pressure, and metal sulfides are directly oxidized to form sulfates, thereby further reducing the consumption of sulfuric acid.Metals can be dissolved more efficiently under elevated oxygen pressure conditions, and the residual amount of metals in the leaching residue is reduced, resulting in significantly increased copper and cobalt leaching rates while reducing sulfuric acid consumption, and significantly reducing metal losses in high calcium and high magnesium copper-cobalt ore.

[0033] To summarize, according to an embodiment of the present invention, a method of sequential sulfide and oxide flotation and beneficiation in a combined leaching process at atmospheric pressure and oxidative leaching at elevated pressure is used to efficiently leach copper and cobalt in a copper-cobalt ore with a high calcium and magnesium content. The flotation and magnetic separation processes produce a copper-cobalt roughing sulfide concentrate, a copper-cobalt roughing oxide concentrate, and a cobalt concentrate after magnetic separation. Thereafter, the copper-cobalt sulfide concentrate is calcined to obtain a calcined residue and an off-gas, and the calcined residue is sent to leaching at atmospheric pressure to obtain a copper-cobalt leachate and a leaching residue containing unleached copper-cobalt complex sulfide.Finally, the leaching residue, copper-cobalt oxide concentrate, and cobalt concentrate from magnetic separation are sent to oxidative leaching at elevated pressure to produce a copper-cobalt leachate with a high metal leaching rate. According to an embodiment of the present invention, process simplicity, relatively low cost, and relatively high copper and cobalt recovery rates are achieved, with a total cobalt recovery rate of at least 96% and a total copper recovery rate of at least 97%.

[0034] According to the embodiment, in step S1, the solid content of the ore pulp is from 20 to 40%, which can improve the fluidity and stability of the ore pulp, while reducing the amount of liquid to be processed in the subsequent leaching process, and reducing the energy consumption and cost of wastewater treatment. This is favorable for the uniform distribution of flotation reagents and the collection effect, and further increases the efficiency of copper and cobalt recovery. According to the embodiment, step S1 further comprises grinding copper-cobalt ore with a high calcium and magnesium content to obtain ground ore and adding water to the ground ore to obtain ore pulp. From 65 to 85% by mass of the ground ore has a particle size of not more than 0.074 mm.

[0035] By optimizing the particle size of the crushed ore and achieving a uniform and relatively small particle size, more complete dissociation of copper-cobalt minerals and gangue can be achieved. This is favorable for the efficient collection of copper-cobalt minerals during subsequent flotation and reduces the adverse effects of undissociated minerals on metal recovery. Furthermore, by adjusting the grinding degree, the concentrate grade can be significantly improved, the amount of ore in the subsequent processing stage can be reduced, the overall production cost can be further reduced, the ore processing process from the source can be optimized, energy consumption, material consumption, and processing costs can be effectively reduced, and the recovery rates of copper and cobalt can be further improved.

[0036] For the purpose of significantly improving the efficiency of copper and cobalt extraction from a feedstock which is a copper-cobalt ore with a high calcium and magnesium content, while reducing the cost of the reagents used and the energy consumption, according to the embodiment, in step S1, the first collector contains one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate and O-isopropyl ethyl thiocarbamate (Z-200), which are added in an amount of 50 to 300 g / t, and / or the first flotation is carried out for a period of time of 2 to 10 minutes, while the mixing duration is from 1 to 5 minutes. According to the embodiment, the regulator, the first collector and the first frother are sequentially added to the ore pulp for the first flotation.The regulator contains one or more substances selected from the following: calcium oxide, calcium hydroxide and calcium carbonate in order to establish the pH value of the ore pulp at a level of 7 to 10, and the first foaming agent contains pinitol oil, which is added in an amount of 20 to 50 g / t.

[0037] The above-mentioned first collector, having a specific chemical structure, can form a stable hydrophobic film on the surface of copper-cobalt sulfide minerals, significantly enhancing the hydrophobicity of the minerals. Thus, the separation of copper-cobalt minerals from gangue is more efficient during flotation. By adjusting the added amount within the above-mentioned range, the collection effect can be further enhanced, while reducing the increased cost and unnecessary consumption of reagents due to excessive addition. By adjusting the stirring duration within the above-mentioned range during flotation, the distribution of reagents becomes more uniform, while maintaining relatively low energy consumption.By adjusting flotation duration within the above-mentioned range, recovery can be further increased while maintaining relatively high process efficiency. Optimizing mixing and flotation durations facilitates efficient energy consumption reduction while ensuring complete contact and selective separation of minerals.

[0038] The above-mentioned regulator can create an alkaline environment that is more favorable for the flotation of copper-cobalt minerals, reduce the interference of harmful minerals, and improve flotation selectivity. The above-mentioned frother not only promotes bubble formation and enhances bubble stability but also further enhances contact between minerals and reagents, which is conducive to improved flotation efficiency and recovery.

[0039] According to the embodiment, in step S2, the reducing agent comprises one or more substances selected from the following: sodium carbonate, sodium sulfate and sodium chloride, and / or the weight ratio of the copper-cobalt sulfide concentrate from rough processing and the reducing agent is from 1:0.2 to 1:0.5, and / or calcination is carried out at a temperature of from 400 to 600°C for a period of from 2 to 4 hours. The reducing agent can facilitate the oxidation-reduction reactions of copper-cobalt sulfide minerals at a relatively low calcination temperature to form metal salts that are easily leached by acid, which not only increases the solubility of the metal, but also produces a sulfur fixation effect, reducing sulfur dioxide emissions during calcination, which is beneficial for environmental protection and subsequent acid regeneration.

[0040] By adjusting the mass ratio of the rough processing copper-cobalt sulfide concentrate and the reducing agent within the above-mentioned range, it is more favorable to ensure complete contact and reaction between the reducing agent and the metal sulfide, while minimizing the incompleteness of conversion caused by an insufficient amount of reducing agent, or preventing additional costs and possible increase in the amount of residue caused by an excessive amount of reducing agent, and thus achieving a balance between economy and efficiency.By controlling the calcination temperature and duration, it is beneficial to achieve efficient conversion of metal sulfides, ensure proper decomposition of sulfides, increase metal leaching rates, and at the same time reduce excessive oxidation of minerals at high temperature or the formation of insoluble by-products such as metal oxides, so as to better control energy consumption and reduce production costs.

[0041] According to the embodiment, step S2 further comprises adding water to the exhaust gas to produce sulfuric acid and returning the sulfuric acid to atmospheric leaching and / or high-pressure oxidative leaching. The sulfur dioxide generated during the calcination of the copper-cobalt sulfide concentrate from rough processing is then reused to produce acid, and this acid is returned to atmospheric leaching and high-pressure oxidative leaching, thereby further reducing environmental pollution, conserving resources, and reducing production costs.

[0042] According to an embodiment of the present invention, by optimizing the leaching parameters, the economic and environmental performance are significantly improved when the processed raw material is a copper-cobalt ore with a high calcium and magnesium content, and at the same time, the metal recovery rate is increased. According to the embodiment, in step S3, the acid-to-ore ratio for leaching at atmospheric pressure is from 180 to 280 kg / t, the liquid-to-solid ratio is from 3:1 to 5:1, and the stirring speed is from 300 to 600 rpm, and / or leaching at atmospheric pressure is carried out at a temperature of from 25 to 90°C for a period of from 60 to 240 minutes, and the pH value of the solution at the end point of leaching is from 0.8 to 2.5.

[0043] By optimizing the acid-ore ratio for atmospheric pressure leaching and the liquid-to-solid ratio, acid consumption during leaching can be effectively controlled, reducing the increased costs and environmental pollution caused by adding excess acid. Meanwhile, a relatively low liquid-to-solid ratio can further reduce the amount of liquid in the subsequent process stage, reducing energy consumption and processing costs. Increasing the stirring speed can accelerate mass transfer between the ore pulp and the liquid acid, increasing the leaching rate, shortening the leaching time, and improving process efficiency.

[0044] Setting the leaching temperature and duration within the above-mentioned range improves the likelihood of simultaneously ensuring complete dissolution of copper-cobalt minerals, increasing metal recovery, reducing unnecessary energy consumption and equipment wear due to high temperatures, and achieving a balance between reaction rate and energy consumption. Setting the pH of the solution at the final leaching point within the above-mentioned range improves the likelihood of stable metal ion existence in an acidic environment and reduces the risk of secondary precipitation, creating favorable conditions for subsequent processing.

[0045] According to the embodiment, in step S4, the sulfonating agent comprises sodium sulfide and / or sodium hydrosulfide, which are added in an amount of 1000 to 3000 g / t, and / or the second collector comprises one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate, potassium amyl xanthate or sodium amyl xanthate, which are added in an amount of 500 to 2000 g / t, and / or sulfonation is carried out for a period of time of 30 to 80 minutes, and / or the second flotation is carried out for a period of time of 2 to 10 minutes, wherein the mixing duration is from 2 to 6 minutes. According to the embodiment, the sulfonating agent is added to the copper-cobalt sulfide roughing tailings for sulfonation, and then the second collector, the second frother and the inhibitor are sequentially added for the second flotation.The second foaming agent contains pinitol oil, which is added in an amount of 20 to 50 g / t, and the inhibitor contains sodium hexametaphosphate and / or carboxymethylcellulose, which are added in an amount of 40 to 200 g / t.

[0046] The above-mentioned sulfonating agent can not only effectively activate copper-cobalt sulfide minerals to improve collection efficiency during subsequent flotation, but also reduce the increased cost and potential inhibition caused by excessive addition. By adjusting the addition amount of the second collector within the above-mentioned range, it is more favorable to improve the selective collection of copper-cobalt minerals and reduce the intrusion of accompanying gangue, thereby effectively reducing the amount of ore in the subsequent process stage, reducing energy and reagent consumption, and lowering overall production costs. By optimizing the sulfonation duration, it is favorable to more completely complete the sulfonation reaction, enhance the surface modification of minerals and the adsorption of reagents, and ensure conditions for effective subsequent flotation.By optimizing the mixing duration and flotation duration for the second flotation, it is found that more complete contact of the reagents with the minerals is achieved while simultaneously regulating unnecessary energy consumption, the destruction or excessive activation of minerals during prolonged mixing is reduced, and the quality of the concentrate and the degree of metal recovery are further improved.

[0047] Adding a second frother can promote bubble formation, increase the likelihood of mineral-bubble bonding, and improve flotation efficiency. The use of the aforementioned inhibitor is beneficial for controlling the flotation of harmful gangue and reducing copper and cobalt losses during flotation, thereby further increasing copper and cobalt recovery.

[0048] In order to more completely and specifically extract cobalt traces encapsulated within limonite from copper-cobalt oxide roughing tailings, effectively remove non-magnetic gangue, improve the cobalt recovery rate, and reduce the cost of subsequent processing, according to the embodiment, in step S5, the intensity of the background magnetic field for magnetic separation is from 0.3 to 2.0 T. According to the embodiment, the magnetic separation includes preliminary magnetic separation, purification magnetic separation, and final magnetic separation, which are carried out sequentially. The aforementioned high-gradient magnetic separation provides increased selectivity, which makes it possible to effectively separate weakly magnetic cobalt oxide minerals, reduce the intrusion of strongly magnetic gangue, and reduce the amount of ore and energy consumption for subsequent processing.

[0049] According to the embodiment, the background magnetic field intensity for the preliminary magnetic separation is 1.2 to 1.5 T, the background magnetic field intensity for the purifying magnetic separation is 0.9 to 1.1 T, and the background magnetic field intensity for the final magnetic separation is 0.75 to 0.85 T. Under the above-mentioned preliminary magnetic separation conditions, the bulk of the cobalt magnetic minerals can be pre-collected. The background magnetic field intensity for the purifying magnetic separation is used to further upgrade the concentrate grade and remove non-magnetic minerals, thereby achieving high-purity cobalt recovery.Under the conditions of the aforementioned final magnetic separation, it becomes more feasible to recover trace magnetic cobalt minerals that may be lost during preliminary magnetic separation and purification magnetic separation. This reduces unnecessary resource consumption and further increases overall cobalt recovery. A specific multi-stage magnetic separation process can not only ensure efficient cobalt resource recovery from copper-cobalt oxide roughing tailings and reduce the cost of direct leaching, but also improve the cobalt concentrate grade and lay a solid foundation for subsequent cost-effective and highly efficient metal recovery.

[0050] According to the embodiment, in step S6, the acid-to-ore ratio for the high-pressure oxidative leaching is from 180 to 220 kg / t, the liquid-to-solid ratio is from 6:1 to 10:1, and the stirring speed is from 600 to 800 rpm, and / or the high-pressure oxidative leaching is carried out at a temperature of from 160 to 220°C for 0.8 to 2 hours, the oxygen partial pressure is from 0.3 to 0.8 MPa, and the pH value of the solution at the end point of leaching is from 1.2 to 2.0. By precisely controlling the acid-ore ratio and the liquid-solid ratio, the complete contact between the liquid acid and the ore can be facilitated, thereby accelerating the dissolution of copper and cobalt metals, reducing excess acid consumption, lowering costs, and minimizing environmental pollution.

[0051] By adjusting the temperature, duration, and partial pressure of oxygen for oxidative leaching at elevated pressure within the above-mentioned range, it is possible to ensure ideal thermodynamic and dynamic conditions for oxidative leaching at elevated pressure. The oxidation reaction rate can be accelerated at the above-mentioned temperature, and sufficient oxygen introduction at high pressure is suitable for the complete oxidation of difficult-to-leach metal sulfides and oxides, which promotes the transfer of metal ions into solution and, in particular, significantly improves the leaching efficiency of residual copper-cobalt sulfide ore and copper-cobalt oxide ore during pre-processing.By adjusting the pH of the solution at the final leaching point and creating an acidic environment, the stable existence of copper and cobalt metal ions is possible, thereby increasing the degree of metal leaching and the efficiency of subsequent separation / purification. On the one hand, the conditions of the aforementioned oxidative leaching at elevated pressure can increase the solubility and leaching rates of metals in complex copper-cobalt ore with high calcium and magnesium content. On the other hand, these conditions are favorable for reducing unwanted side reactions and wasteful resource use, thereby achieving a balance between cost and environmental protection while simultaneously increasing copper and cobalt recovery rates.

[0052] Flotation of the first leaching residue can further reduce the amount of residue that must undergo oxidative leaching at elevated pressure. According to the embodiment, in step S6, the first leaching residue is subjected to third flotation to obtain a copper-cobalt sulfide enriched leaching residue. Then, the copper-cobalt sulfide enriched leaching residue, the copper-cobalt oxide concentrate from rough processing, and the cobalt oxide concentrate from magnetic separation are mixed, and then water and sulfuric acid are added for oxidative leaching at elevated pressure.By directing the primary leaching residue to beneficiation processing in the third flotation process, non-metallic minerals and low-value components can be effectively removed, thereby reducing the amount of ineffective ore during high-pressure oxidative leaching, decreasing liquid acid and oxygen consumption, and lowering costs. By mixing copper-cobalt sulfide concentrate from leaching, copper-cobalt oxide concentrate from roughing, and cobalt oxide concentrate from magnetic separation for high-pressure oxidative leaching, the synergistic effect of copper-cobalt minerals in various forms can be used to improve leaching efficiency and metal recovery rates, particularly for residual copper-cobalt sulfide minerals.By implementing oxidative leaching at elevated pressure, more complete dissolution of metals can be achieved under conditions of high temperature, high pressure and a strong oxidizing agent environment, and the efficiency of extracting complex copper and cobalt sulfides is significantly increased.

[0053] According to the embodiment, the third flotation includes adding water to adjust the solid content of the ore pulp to a level of 25 to 35%, adding an additional regulator to adjust the pH value of the ore pulp to 7 to 9, and then sequentially adding an additional collector and an additional frother for the third flotation.According to an embodiment, the additional regulator contains one or more substances selected from the following: calcium oxide, calcium hydroxide and calcium carbonate, the additional collector contains one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate and O-isopropyl ethyl thiocarbamate, which are added in an amount of 40 to 60 g / t, and the additional frother contains pinitol oil, which is added in an amount of 10 to 30 g / t, and / or the third flotation is carried out for a period of time of 2 to 10 minutes, wherein the mixing duration is from 1 to 5 minutes.

[0054] The above conditions are favorable for further accelerating the reaction between metal-bearing minerals and reagents, improving selectivity and efficiency during flotation, reducing metal losses, and increasing concentrate purity. Through pre-concentration processing and precise control of flotation conditions, copper and cobalt recovery rates can be significantly increased, the high-pressure oxidative leaching process can be optimized, and costs can be reduced.

[0055] According to the embodiment, the copper-cobalt ore with a high calcium and magnesium content has a Cu content of 0.5 to 5 wt%, a Co content of 0.1 to 1 wt%, an MgO content of 8 to 15 wt%, a CaO content of 9 to 16 wt%, and an S content of 0.2 to 0.6 wt%. Since the ore has a high content of calcium oxide and magnesium oxide, and if acid leaching is carried out directly, a large amount of liquid acid may be consumed, and the processing cost may significantly increase. At the same time, copper in the ore is present mainly in the form of sulfide, cobalt acid oxide liquid, and the sulfur content is moderate, which can provide more advanced material conditions in which sequential sulfide and oxide flotation and combined leaching at atmospheric pressure and at elevated oxygen pressure should be carried out according to the embodiment of the present invention.For an ore having a high content of CaO and MgO, according to an embodiment of the present invention, said acid-consuming gangue is effectively removed using flotation, leaching and similar processes, and as a result, collector consumption and acid consumption during subsequent acid leaching are reduced, costs are reduced, complete extraction of copper and cobalt is ensured, and a relatively high overall degree of metal extraction is achieved.

[0056] By way of illustration, but not limitation, in stage S1, the added amount of the first collector is 50 g / t, 100 g / t, 150 g / t, 200 g / t, 250 g / t, 300 g / t, or is within the range limited by any two of the specified numerical values.

[0057] By way of illustration, but not limitation, in step S2, the weight ratio of the copper-cobalt sulfide roughing concentrate to the reducing agent is 1:0.2, 1:0.3, 1:0.4, 1:0.5, or is within the range defined by any two of the said numerical values.

[0058] By way of illustration, but not limitation, in step S2, calcination is carried out at a temperature of 400°C, 450°C, 500°C, 550°C, 600°C, or within a range defined by any two of the said numerical values, while the calcination duration is 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, or within a range defined by any two of the said numerical values.

[0059] By way of illustration, but not limitation, in step S4, the added amount of sulfonating agent is 1000 g / t, 1500 g / t, 2000 g / t, 2500 g / t, 3000 g / t, or is within the range limited by any two of the said numerical values.

[0060] By way of illustration, but not limitation, at stage S4, the added amount of the second collector is 500 g / t, 1000 g / t, 1500 g / t, 2000 g / t, or is within the range limited by any two of the specified numerical values.

[0061] By way of illustration, but not limitation, in step S4, the duration of sulfonation is 30 minutes, 40 minutes, 50 minutes, 60 minutes, 70 minutes, 80 minutes, or is within the range limited by any two of the specified numerical values.

[0062] As an illustration, but not limitation, in step S5, the intensity of the background magnetic field for magnetic separation is 0.3 T, 0.5 T, 1.0 T, 1.5 T, 2.0 T, or is within the range limited by any two of the said numerical values.

[0063] By way of illustration, but not limitation, in step S6, the oxidative leaching under elevated pressure is carried out at a temperature of 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, or within the range limited by any two of the said numerical values, while the duration of the oxidative leaching under elevated pressure is 0.8 hours, 1.0 hours, 1.2 hours, 1.5 hours, 1.8 hours, 2 hours, or within the range limited by any two of the said numerical values. The partial pressure of oxygen is 0.3 MPa, 0.4 MPa, 0.5 MPa, 0.6 MPa, 0.7 MPa, 0.8 MPa, or within the range limited by any two of the said numerical values.

[0064] Next, the present invention will be described in more detail by providing specific examples, which should not be construed as limiting the scope of legal protection claimed in the present invention.

[0065] Example 1

[0066] The flow chart of the method is illustrated in Fig. 1.

[0067] A method for the combined enrichment and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium was implemented. The copper-cobalt ore with a high content of calcium and magnesium had a Cu content of 3.21 wt.%, a Co content of 0.23 wt.%, a MgO content of 10.93 wt.%, a CaO content of 12.31 wt.%, and a S content of 0.47 wt.%. The method included steps S1-S6.

[0068] In the S1 stage, copper-cobalt ore with high calcium and magnesium content was crushed to obtain crushed ore, with 75% of the crushed ore having a particle size of no more than 0.074 mm. Water was added to the crushed ore to obtain ore pulp, with the solids content of the ore pulp being 30%.A regulator, a first collector and a first frother were added sequentially to the ore pulp for the first flotation to obtain a copper-cobalt sulphide roughing concentrate and copper-cobalt sulphide roughing tailings, wherein the regulator was calcium oxide in order to adjust the pH of the ore pulp to 8, the first collector was amyl xanthate, which was added in an amount of 100 g / t, the first frother was pinitol oil, which was added in an amount of 30 g / t, and the first flotation was carried out for a period of time of 3 minutes, while the mixing duration was 2 minutes.

[0069] In step S2, a reducing agent was added to the copper-cobalt sulfide concentrate from the rough processing stage for calcination to obtain a calcined residue and an off-gas. The reducing agent was sodium carbonate, the weight ratio of the copper-cobalt sulfide concentrate from the rough processing stage and the reducing agent was 1:0.3, and calcination was carried out at a temperature of 500°C for 2 hours. Water was added to the off-gas to obtain sulfuric acid, and the sulfuric acid was returned to atmospheric pressure leaching and high-pressure oxidative leaching.

[0070] In step S3, water and sulfuric acid were added to the calcined residue, and then atmospheric pressure leaching was carried out. The acid-to-ore ratio was 280 kg / t, the liquid-to-solid ratio was 4:1, the stirring speed was 500 rpm, atmospheric pressure leaching was carried out at a temperature of 80 °C for 120 minutes, and the pH value of the solution at the end point of leaching was 0.8. After that, solid-liquid separation was carried out to obtain the first leaching product and the first leaching residue.

[0071] In the S4 step, a sulfonating agent was added to the copper-cobalt sulfide tailings of rough processing for sulfonation, wherein the sulfonating agent was sodium hydrosulfide, which was added in an amount of 2000 g / t, and sulfonation was carried out for 60 minutes. Thereafter, a second collector, a second frother and an inhibitor were sequentially added for a second flotation to obtain a copper-cobalt oxide roughing concentrate and copper-cobalt oxide roughing tailings, wherein the second collector was potassium amyl xanthate, which was added in an amount of 1500 g / t, the second frother was pinitol oil, which was added in an amount of 30 g / t, the inhibitor was sodium hexametaphosphate, which was added in an amount of 80 g / t, and the second flotation was carried out for a period of time of 3 minutes, while the mixing duration was 2 minutes.

[0072] In step S5, preliminary magnetic separation, refining magnetic separation, and final magnetic separation of copper-cobalt oxide tailings from rough processing were sequentially carried out to obtain cobalt oxide concentrate after magnetic separation and cobalt oxide tailings after magnetic separation, wherein the background magnetic field intensity for the preliminary magnetic separation was 1.3 T, the background magnetic field intensity for the refining magnetic separation was 1.0 T, and the background magnetic field intensity for the final magnetic separation was 0.8 T.

[0073] In the S6 step, water, an additional regulator, an additional collector, and an additional frother were sequentially added to the first leaching residue for the third flotation to obtain a copper-cobalt sulfide enriched leaching residue, wherein water was added to adjust the solid content of the ore pulp to 30%, the additional regulator was calcium oxide CaO to adjust the pH of the ore pulp to 8, the additional collector was amyl xanthate, which was added in an amount of 50 g / t, the additional frother was pinitol oil, which was added in an amount of 20 g / t, and the third flotation was carried out for a period of 3 minutes, with a stirring time of 2 minutes.The copper-cobalt sulfide concentrate after leaching, the copper-cobalt oxide concentrate of rough processing and the cobalt oxide concentrate after magnetic separation were mixed, and then water and sulfuric acid were added for oxidative leaching under elevated pressure, wherein the acid-to-ore ratio was 200 kg / t, the liquid-to-solid ratio was 8:1, the stirring speed was 800 rpm, the oxidative leaching under elevated pressure was carried out at a temperature of 200 °C for 1 hour, the oxygen partial pressure was 0.4 MPa, and the pH value of the solution at the end point of leaching was 1.4. Then, solid-liquid separation was carried out, and the second leach product and the second leach residue were obtained.

[0074] Example 2

[0075] The flow chart of the method is illustrated in Fig. 2.

[0076] A method for the combined enrichment and metallurgical processing of copper-cobalt ore with high calcium and magnesium content was implemented. The composition of the copper-cobalt ore with high calcium and magnesium content was the same as in Example 1. The method included steps S1–S6.

[0077] In the S1 stage, copper-cobalt ore with high calcium and magnesium content was crushed to obtain crushed ore, with 75% of the crushed ore having a particle size of no more than 0.074 mm. Water was added to the crushed ore to obtain ore pulp, with the solids content of the ore pulp being 30%.A regulator, a first collector and a first frother were added sequentially to the ore pulp for the first flotation to obtain a copper-cobalt sulphide roughing concentrate and copper-cobalt sulphide roughing tailings, wherein the regulator was calcium oxide in order to adjust the pH of the ore pulp to 8, the first collector was amyl xanthate, which was added in an amount of 100 g / t, the first frother was pinitol oil, which was added in an amount of 30 g / t, and the first flotation was carried out for a period of time of 3 minutes, while the mixing duration was 2 minutes.

[0078] In step S2, a reducing agent was added to the copper-cobalt sulfide roughing concentrate for calcination to obtain a calcined residue and an off-gas. The reducing agent was sodium carbonate, which was added in an amount of 40 g, the weight ratio of the copper-cobalt sulfide roughing concentrate to the reducing agent was 1:0.3, and calcination was carried out at a temperature of 500°C for a period of 2 hours. Water was added to the off-gas to obtain sulfuric acid, and the sulfuric acid was returned to atmospheric pressure leaching and pressure oxidative leaching.

[0079] In step S3, water and sulfuric acid were added to the calcined residue, and then atmospheric pressure leaching was carried out. The acid-to-ore ratio was 280 kg / t, the liquid-to-solid ratio was 4:1, the stirring speed was 500 rpm, atmospheric pressure leaching was carried out at a temperature of 80 °C for 120 minutes, and the pH value of the solution at the end point of leaching was 0.8. After that, solid-liquid separation was carried out to obtain the first leaching product and the first leaching residue.

[0080] In the S4 step, a sulfonating agent was added to the copper-cobalt sulfide tailings of rough processing for sulfonation, and the sulfonating agent was sodium hydrosulfide, which was added in an amount of 2000 g / t, and sulfonation was carried out for 60 minutes. Thereafter, the second collector, the second frother and the inhibitor were sequentially added for the second flotation to obtain a copper-cobalt oxide roughing concentrate and copper-cobalt oxide roughing tailings, wherein the second collector was potassium amyl xanthate, which was added in an amount of 1500 g / t, the second frother was pinitol oil, which was added in an amount of 30 g / t, the inhibitor was sodium hexametaphosphate, which was added in an amount of 80 g / t, and the second flotation was carried out for a period of time of 3 minutes, while the mixing duration was 2 minutes.

[0081] In step S5, preliminary magnetic separation, refining magnetic separation, and final magnetic separation of copper-cobalt oxide tailings from rough processing were sequentially carried out to obtain cobalt oxide concentrate after magnetic separation and cobalt oxide tailings after magnetic separation, wherein the background magnetic field intensity for the preliminary magnetic separation was 1.3 T, the background magnetic field intensity for the refining magnetic separation was 1.0 T, and the background magnetic field intensity for the final magnetic separation was 0.8 T.

[0082] In step S6, the first leaching residue, the rough processing copper-cobalt oxide concentrate, and the magnetic separation cobalt oxide concentrate were mixed, and then water and sulfuric acid were added for pressure oxidative leaching, wherein the acid-to-ore ratio was 200 kg / t, the liquid-to-solid ratio was 8:1, the stirring speed was 800 rpm, the pressure oxidative leaching was carried out at a temperature of 200 °C for 1 hour, the oxygen partial pressure was 0.4 MPa, and the pH value of the solution at the end point of leaching was 1.4. Thereafter, solid-liquid separation was carried out, and the second leaching product and the second leaching residue were obtained.

[0083] Example 3

[0084] The difference from Example 1 was that in step S1, copper-cobalt ore with high calcium and magnesium content was crushed to obtain crushed ore, with 65% by weight of the crushed ore having a particle size of no more than 0.074 mm. Water was added to the crushed ore to obtain ore pulp, with the solids content of the ore pulp being 40%.A regulator, a first collector and a first frother were added sequentially to the ore pulp for the first flotation to obtain a copper-cobalt sulphide roughing concentrate and copper-cobalt sulphide roughing tailings, wherein the regulator was calcium hydroxide in order to adjust the pH of the ore pulp to 7, the first collector was ethyl xanthate, which was added in an amount of 50 g / t, the first frother was pinitol oil, which was added in an amount of 20 g / t, and the first flotation was carried out for a period of time of 10 minutes, while the mixing duration was 5 minutes.

[0085] Example 4

[0086] The difference from Example 1 was that in step S1, copper-cobalt ore with high calcium and magnesium content was crushed to obtain crushed ore, with 85% of the crushed ore having a particle size of no more than 0.074 mm. Water was added to the crushed ore to obtain ore pulp, with the solids content of the ore pulp being 20%.A regulator, a first collector and a first frother were added sequentially to the ore pulp for the first flotation to produce a copper-cobalt sulphide roughing concentrate and copper-cobalt sulphide roughing tailings, wherein the regulator was calcium carbonate in order to adjust the pH of the ore pulp to 10, the first collector was butyl xanthate, which was added in an amount of 300 g / t, the first frother was No. 2 oil (trade name for pinitol oil), which was added in an amount of 50 g / t, and the first flotation was carried out for a period of 2 minutes, while the mixing duration was 1 minute.

[0087] Example 5

[0088] The difference from Example 1 is that in Step S2, a reducing agent was added to the copper-cobalt sulfide roughing concentrate for calcination to obtain a calcined residue and an off-gas, wherein the reducing agent was sodium sulfate, the weight ratio of the copper-cobalt sulfide roughing concentrate to the reducing agent was 1:0.2, and calcination was carried out at a temperature of 400°C for a period of 4 hours. Water was added to the off-gas to obtain sulfuric acid, and the sulfuric acid was returned to atmospheric pressure leaching and high-pressure oxidative leaching.

[0089] Example 6

[0090] The difference from Example 1 is that in step S2, a reducing agent was added to the copper-cobalt sulfide roughing concentrate for calcination to obtain a calcined residue and an off-gas, wherein the reducing agent was sodium chloride, the weight ratio of the copper-cobalt sulfide roughing concentrate to the reducing agent was 1:0.5, and calcination was carried out at a temperature of 600°C for a period of 2 hours. Water was added to the off-gas to obtain sulfuric acid, and the sulfuric acid was returned to atmospheric pressure leaching and high-pressure oxidative leaching.

[0091] Example 7

[0092] The difference from Example 1 is that in step S3, water and sulfuric acid were added to the calcined residue, and then leaching was carried out at atmospheric pressure, the acid-to-ore ratio was 180 kg / t, the liquid-to-solid ratio was 4:1, the stirring speed was 300 rpm, leaching at atmospheric pressure was carried out at a temperature of 25 °C for 240 minutes, and the pH value of the solution at the end point of leaching was 2.5. After that, solid-liquid separation was carried out, and the first leaching product and the first leaching residue were obtained.

[0093] Example 8

[0094] The difference from Example 1 is that in step S3, water and sulfuric acid were added to the calcined residue, and then leaching was carried out at atmospheric pressure, the acid-to-ore ratio was 280 kg / t, the liquid-to-solid ratio was 4:1, the stirring speed was 600 rpm, leaching at atmospheric pressure was carried out at a temperature of 90 °C for 60 minutes, and the pH value of the solution at the end point of leaching was 0.8. After that, solid-liquid separation was carried out, and the first leaching product and the first leaching residue were obtained.

[0095] Example 9

[0096] The difference from Example 1 was that in the S4 step, a sulfonating agent was added to the copper-cobalt sulfide tailings from rough processing for sulfonation, and the sulfonating agent was sodium sulfide, which was added in an amount of 1000 g / t, and sulfonation was carried out for 80 minutes.Thereafter, a second collector, a second frother and an inhibitor were sequentially added for a second flotation to obtain a copper-cobalt oxide roughing concentrate and copper-cobalt oxide roughing tailings, wherein the second collector was amyl xanthate, which was added in an amount of 500 g / t, the second frother was pinitol oil, which was added in an amount of 20 g / t, the inhibitor was sodium hexametaphosphate, which was added in an amount of 40 g / t, and the second flotation was carried out for a period of time of 10 minutes, while the mixing duration was 6 minutes.

[0097] Example 10

[0098] The difference from Example 1 was that, in the S4 step, a sulfonating agent was added to the copper-cobalt sulfide tailings from rough processing for sulfonation, and the sulfonating agent was sodium hydrosulfide, which was added in an amount of 3000 g / t, and sulfonation was carried out for 30 minutes.Thereafter, a second collector, a second frother and an inhibitor were sequentially added for a second flotation to produce a copper-cobalt oxide roughing concentrate and copper-cobalt oxide roughing tailings, wherein the second collector was sodium amyl xanthate, which was added in an amount of 2000 g / t, the second frother was oil No. 2, which was added in an amount of 50 g / t, the inhibitor was carboxymethyl cellulose, which was added in an amount of 200 g / t, and the second flotation was carried out for a period of time of 2 minutes, while the mixing duration was 2 minutes.

[0099] Example 11

[0100] The difference from Example 1 is that in step S5, the preliminary magnetic separation, the refining magnetic separation, and the final magnetic separation of the copper-cobalt oxide tailings from the roughing were sequentially carried out to obtain the cobalt oxide concentrate after magnetic separation and the cobalt oxide tailings after magnetic separation, wherein the background magnetic field intensity for the preliminary magnetic separation was 1.2 T, the background magnetic field intensity for the refining magnetic separation was 0.9 T, and the background magnetic field intensity for the final magnetic separation was 0.75 T.

[0101] Example 12

[0102] The difference from Example 1 is that in step S5, the preliminary magnetic separation, the refining magnetic separation, and the final magnetic separation of the copper-cobalt oxide tailings from the roughing were sequentially carried out to obtain the cobalt oxide concentrate after magnetic separation and the cobalt oxide tailings after magnetic separation, wherein the background magnetic field intensity for the preliminary magnetic separation was 1.5 T, the background magnetic field intensity for the refining magnetic separation was 1.1 T, and the background magnetic field intensity for the final magnetic separation was 0.85 T.

[0103] Example 13

[0104] The difference from Example 1 is that, in step S6, water, an additional regulator, an additional collector and an additional frother were sequentially added to the first leaching residue for the third flotation to obtain a copper-cobalt sulfide enriched leaching residue, wherein water was added to adjust the solid content of the ore pulp to 25%, the additional regulator was calcium hydroxide to adjust the pH of the ore pulp to 7, the additional collector was ethyl xanthate added in an amount of 40 g / t, the additional frother was pinitol oil added in an amount of 10 g / t, and the third flotation was carried out for a period of 10 minutes, with a stirring duration of 5 minutes.The copper-cobalt sulfide concentrate after leaching, the copper-cobalt oxide concentrate of rough processing and the cobalt oxide concentrate after magnetic separation were mixed, and then water and sulfuric acid were added for oxidative leaching under elevated pressure, wherein the acid-to-ore ratio was 180 kg / t, the liquid-to-solid ratio was 10:1, the stirring speed was 600 rpm, the oxidative leaching under elevated pressure was carried out at a temperature of 160 °C for 2 hours, the oxygen partial pressure was 0.8 MPa, and the pH value of the solution at the end point of leaching was 2.0. Then, solid-liquid separation was carried out, and the second leach product and the second leach residue were obtained.

[0105] Example 14

[0106] The difference from Example 1 is that, in step S6, water, an additional regulator, an additional collector and an additional frother were sequentially added to the first leaching residue for the third flotation to obtain a copper-cobalt sulfide enriched leaching residue, wherein water was added to adjust the solid content of the ore pulp to 35%, the additional regulator was calcium carbonate to adjust the pH of the ore pulp to 9, the additional collector was butyl xanthate added in an amount of 60 g / t, the additional frother was No. 2 oil added in an amount of 30 g / t, and the third flotation was carried out for a period of 2 minutes, with a stirring duration of 1 minute.The copper-cobalt sulfide concentrate after leaching, the copper-cobalt oxide concentrate of rough processing and the cobalt oxide concentrate after magnetic separation were mixed, and then water and sulfuric acid were added for oxidative leaching under elevated pressure, wherein the acid-to-ore ratio was 220 kg / t, the liquid-to-solid ratio was 6:1, the stirring speed was 800 rpm, the oxidative leaching under elevated pressure was carried out at a temperature of 220 °C for 0.8 hour, the oxygen partial pressure was 0.3 MPa, and the pH value of the solution at the end point of leaching was 1.2. Then, solid-liquid separation was carried out, and the second leach product and the second leach residue were obtained.

[0107] Example 15

[0108] The difference from Example 1 was that the copper-cobalt ore with a high calcium and magnesium content had a Cu content of 0.5 wt.%, a Co content of 0.1 wt.%, a MgO content of 15 wt.%, a CaO content of 9 wt.%, and an S content of 0.2 wt.%.

[0109] Example 16

[0110] The difference from Example 1 was that the copper-cobalt ore with a high calcium and magnesium content had a Cu content of 5 wt.%, a Co content of 1 wt.%, a MgO content of 8 wt.%, a CaO content of 16 wt.%, and an S content of 0.6 wt.%.

[0111] Comparison Example 1

[0112] The difference from Example 2 is that in step S6, the first leaching residue, the copper-cobalt oxide concentrate from rough processing, and the cobalt oxide concentrate after magnetic separation were mixed, and then water and sulfuric acid were added for leaching at atmospheric pressure, wherein the acid-to-ore ratio was 800 kg / t, the liquid-to-solid ratio was 4:1, the stirring speed was 500 rpm, and leaching at atmospheric pressure was carried out at a temperature of 80 °C for 2 hours. Then, solid-liquid separation was carried out, and the leaching product and leaching residue were obtained.

[0113] Comparison Example 2

[0114] The difference from Example 1 was that the copper-cobalt ore with a high calcium and magnesium content was processed according to Example 1 of Patent CN 114950712 A.

[0115] Research results

[0116] In the above examples 1-16 and comparative examples 1 and 2, the metal contents were determined, and the total recovery of cobalt and the total recovery of copper were calculated. The results are presented in Table 1.

[0117] Gross recovery rate of cobalt: the cobalt grade in high-calcium-magnesium copper-cobalt ore, the cobalt grade in the secondary leaching residue, and the cobalt grade in the cobalt oxide tailings after magnetic separation can be determined by atomic absorption spectrometry, and can also be determined by other chemical analysis methods such as inductively coupled plasma mass spectrometry and X-ray fluorescence spectrometry. Gross recovery rate of cobalt = (cobalt grade in high-calcium-magnesium copper-cobalt ore - cobalt grade in the secondary leaching residue - cobalt grade in the cobalt oxide tailings after magnetic separation) / cobalt grade in high-calcium-magnesium copper-cobalt ore.

[0118] Gross copper recovery rate: the copper grade in high-calcium-magnesium copper-cobalt ore, the copper grade in the secondary leaching residue, and the copper grade in the cobalt oxide tailings after magnetic separation can be determined by atomic absorption spectrometry, and can also be determined by other chemical analysis methods such as inductively coupled plasma mass spectrometry and X-ray fluorescence spectrometry. Gross copper recovery rate = (copper grade in high-calcium-magnesium copper-cobalt ore - copper grade in the secondary leaching residue - copper grade in the cobalt oxide tailings after magnetic separation) / copper grade in high-calcium-magnesium copper-cobalt ore.

[0119] As can be seen from the above data, in comparison with Comparative Examples 1 and 2, Examples 1 to 16 of the present invention employ a sequential sulfide and oxide flotation and beneficiation method, which is a combined leaching at atmospheric pressure and oxidative leaching at elevated pressure, to effectively leach copper and cobalt from copper-cobalt ore with a high calcium and magnesium content. As a result of the flotation and magnetic separation processes, copper-cobalt sulfide roughing concentrate, copper-cobalt oxide roughing concentrate, and cobalt concentrate after magnetic separation are obtained.The copper-cobalt sulfide concentrate is then roasted to produce a roasted residue and off-gas, and the roasted residue is sent for leaching at atmospheric pressure to produce a copper-cobalt leachate and a leaching residue containing unleached copper-cobalt complex sulfide. Finally, the leaching residue, copper-cobalt oxide concentrate, and cobalt concentrate after magnetic separation are sent for oxidative leaching at elevated pressure to produce a copper-cobalt leachate with a high metal recovery rate. The method proposed in the examples of the present invention is characterized by simplicity, relatively low cost, and a relatively high copper and cobalt recovery rate.

[0120] In addition, it can be seen that when all the process parameters are within the ranges specified in the examples of the present invention, the overall effect is improved.

[0121] The above description presents only preferred embodiments of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention is subject to various modifications and changes. Any modifications, equivalent substitutions, improvements, and other changes that are made within the spirit and principles of the present invention shall be included within the scope of the legal protection of the present invention.

Claims

1. A method for the combined enrichment and metallurgical processing of copper-cobalt ore with a high content of calcium and magnesium, in which the ore with a high content of calcium and magnesium contains MgO from 8 to 15 wt.% and CaO from 9 to 16 wt.%, including the following stages: stage S1: adding water to the high calcium and magnesium copper-cobalt ore to obtain ore pulp, adding an environment regulator, a first collector and a first frother to the ore pulp for the first flotation to obtain a roughing copper-cobalt sulfide concentrate and roughing copper-cobalt sulfide tailings; Step S2: adding a reducing agent to the rough processing copper-cobalt sulfide concentrate for calcination to obtain a calcined residue and an exhaust gas; step S3: adding water and sulfuric acid to the calcined residue and performing leaching at atmospheric pressure, and then separating the solid and liquid materials to obtain a first leaching product and a first leaching residue; step S4: adding a sulfonating agent to the roughing copper-cobalt sulfide tailings to cause sulfonation, and then adding a second collector, a second frother and a gangue inhibitor to cause a second flotation to obtain a roughing copper-cobalt oxide concentrate and roughing copper-cobalt oxide tailings; step S5: performing magnetic separation of the copper-cobalt oxide tailings from rough processing to obtain a cobalt oxide concentrate after magnetic separation and cobalt oxide tailings after magnetic separation; and Step S6: mixing the first leaching residue, the rough processing copper-cobalt oxide concentrate and the magnetic separation cobalt oxide concentrate, adding water and sulfuric acid to carry out oxidative leaching under high pressure, and then separating the solid and liquid materials to obtain the second leaching product and the second leaching residue.

2. The method according to claim 1, wherein at step S1 the solids content of the ore pulp is from 20 to 40%; and Step S1 further comprises: grinding copper-cobalt ore with a high calcium and magnesium content to obtain ground ore and adding water to the ground ore to obtain ore pulp; wherein from 65 to 85 wt.% of the ground ore has a particle size not exceeding 0.074 mm.

3. The method according to claim 1 or 2, wherein at step S1: the first collector contains one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate and O-isopropyl ethyl thiocarbamate, which are added in an amount of from 50 to 300 g / t; and the first flotation is carried out for a period of time of from 2 to 10 minutes, wherein the mixing duration is 1 to 5 minutes; and an environment regulator, a first collector and a first frother are sequentially added to the ore pulp for the first flotation; wherein the environment regulator contains one or more substances selected from the following: calcium oxide, calcium hydroxide and calcium carbonate, in order to establish a pH value of the ore pulp from 7 to 10, and the first frother is pinitol oil, which is added in an amount of from 20 to 50 g / t.

4. The method according to any one of paragraphs 1-3, in which at step S2: the reducing agent comprises one or more substances selected from the following: sodium carbonate, sodium sulfate or sodium chloride; and the weight ratio of the copper-cobalt sulfide roughing concentrate and the reducing agent is from 1:0.2 to 1:0.5; and the calcination is carried out at a temperature of from 400 to 600 °C for a period of time of from 2 to 4 hours; and Step S2 further comprises: adding water to the exhaust gas to produce sulfuric acid and returning the sulfuric acid to atmospheric pressure leaching and / or elevated pressure oxidative leaching.

5. The method according to any one of paragraphs 1-4, in which at step S3: the acid-to-ore ratio for leaching at atmospheric pressure is 180 to 280 kg / t, the liquid-to-solid ratio is 3:1 to 5:1, and the stirring speed is 300 to 600 rpm; and Atmospheric pressure leaching is carried out at a temperature of 25 to 90°C for a period of 60 to 240 minutes, and the pH value of the solution at the end point of leaching is 0.8 to 2.

5.

6. The method according to any one of paragraphs 1-5, in which at step S4: the sulfonating agent comprises sodium sulfide and / or sodium hydrosulfide, which are added in an amount of from 1000 to 3000 g / t; and / or the second collector comprises one or more substances selected from the following: ethyl xanthate, butyl xanthate, amyl xanthate, potassium amyl xanthate or sodium amyl xanthate, which are added in an amount of from 500 to 2000 g / t; and / or the sulfonation is carried out for a period of time of from 30 to 80 minutes; and / or the second flotation is carried out for a period of time of from 2 to 10 minutes, wherein the mixing duration is from 2 to 6 minutes; and A sulfonating agent is added to the copper-cobalt sulfide roughing tailings for sulfonation, and then a second collector, a second frother, and a gangue inhibitor are sequentially added for the second flotation; wherein the second frother is pinitol oil, which is added in an amount of 20 to 50 g / t, and the inhibitor contains sodium hexametaphosphate and / or carboxymethylcellulose, which are added in an amount of 40 to 200 g / t.

7. The method according to any one of paragraphs 1-6, wherein at step S5; the background magnetic field intensity for magnetic separation is from 0.3 to 2.0 T; and Magnetic separation includes preliminary magnetic separation, cleaning magnetic separation and final magnetic separation, which are carried out sequentially.

8. The method according to any one of paragraphs 1-7, wherein at step S6; the acid-to-ore ratio for the high-pressure oxidative leaching is 180 to 220 kg / t, the liquid-to-solid ratio is 6:1 to 10:1, and the stirring speed is 600 to 800 rpm; and Oxidative leaching at elevated pressure is carried out at a temperature of 160 to 220°C for a period of time of 0.8 to 2 hours, the partial pressure of oxygen is 0.3 to 0.8 MPa, and the pH value of the solution at the end point of leaching is 1.2 to 2.

0.

9. The method according to any one of claims 1 to 8, wherein in step S6 the first leaching residue is subjected to third flotation to obtain a copper-cobalt sulfide enriched leaching residue; then the copper-cobalt sulfide enriched leaching residue, the copper-cobalt roughing oxide concentrate and the cobalt oxide concentrate after magnetic separation are mixed, and water and sulfuric acid are added for oxidative leaching under elevated pressure.

10. The method according to any one of claims 1 to 9, wherein the copper-cobalt ore contains Cu from 0.5 to 5 wt.%, Co content from 0.1 to 1 wt.%, and S from 0.2 to 0.6 wt.%.

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