Treatment method of talc-containing copper cobalt oxide ore

Abstract

The invention discloses a treatment method of talc-containing copper cobalt oxide ores, which utilizes low-copper raffinate to presoak the talc-containing copper cobalt oxide ores, so as to fully utilize sulfuric acid in the low-copper raffinate, save the cost of neutralizing agents in the low-copper raffinate, and reduce the impact on production when the talc-containing copper cobalt oxide ores directly enter a leaching system. Production accidents such as groove overflowing, thickener mixing and three-phase extraction increase are reduced, and the electrodeposition efficiency is guaranteed. The method has the advantage of being low in production cost, the profit and loss balance grade of the copper oxide cobalt ore can be reduced, and development of the low-grade copper oxide cobalt ore is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of copper-cobalt smelting, and in particular to a method for treating talc-containing copper-cobalt oxide ore. Background Art

[0002] Copper and cobalt are strategic metals, essential foundational materials for the development of new energy, 5G communications, aerospace, and defense industries. Currently, China's copper and cobalt resources are scarce, and its dependence on foreign sources is high. In 2020, these foreign dependence rates reached 72% for copper and 96% for cobalt, respectively. Over 90% of primary cobalt production comes from the Democratic Republic of the Congo (DRC).

[0003] The process commonly used for copper-cobalt oxide ores in the Democratic Republic of the Congo involves reductive acid leaching, leaching pulp concentration and thickening, CCD washing of the leaching residue, leachate extraction and electrowinning, CCD washing supernatant (low-copper feed solution) extraction and electrowinning, neutralization and impurity removal of the low-copper raffinate, and cobalt precipitation in the post-impurity removal solution. However, copper-cobalt oxide ores often contain associated talc, and direct leaching into the leaching system can increase acid consumption, bubbling, thickener mixing, increased three-phase extraction, and reduced electrowinning efficiency. Furthermore, the neutralization and impurity removal process for the low-copper raffinate presents challenges such as inefficient utilization of sulfuric acid in the solution and high costs for neutralization agents. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the present invention aims to provide a method for treating talc-containing copper-cobalt oxide ore, so as to achieve low-cost treatment of talc-containing copper-cobalt oxide ore.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for treating talc-containing copper-cobalt oxide ore comprises the following steps:

[0007] S1, mixing the talc-containing copper-cobalt oxide ore with the low-copper raffinate for pre-leaching;

[0008] S2, using a thickener to perform solid-liquid separation on the preleached slurry obtained after the preleaching in step S1 to obtain a preleached underflow and a preleached supernatant;

[0009] S3, adding lime slurry to the pre-leaching supernatant obtained in step S2 to carry out copper precipitation reaction;

[0010] S4, using a thickener to perform solid-liquid separation on the copper precipitation slurry obtained after the copper precipitation reaction in step S3 to obtain copper precipitation residue and copper precipitation supernatant;

[0011] S5. The copper precipitation residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 and returned to the acid leaching system to further recover copper and cobalt; the copper precipitation supernatant obtained in step S4 is subjected to cobalt precipitation using magnesium oxide to obtain a cobalt hydroxide product.

[0012] Furthermore, in step S1, the talc-containing copper-cobalt oxide ore contains Cu 1-5%, Co 0-5%, Ca 0.5-15%, Mg 0.5-15%, Al 0.5-15%, and talc>0.5% by mass, and the particle size of the talc-containing copper-cobalt oxide ore is -200 mesh, accounting for ≥50% by mass.

[0013] Furthermore, in step S1, the low-copper raffinate contains Cu 0-2 g / L, Co 0-5 g / L, and acidity ≥ 5 g / L.

[0014] Furthermore, in step S1, the preleaching temperature is room temperature, the preleaching time is 0.5-3 hours, the preleaching pulp mass concentration is 5%-40%, and the end point pH of the preleaching is 4-5.

[0015] Furthermore, in step S3, the endpoint pH of the copper precipitation reaction is 5.6-6.2.

[0016] Furthermore, in step S5, the copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 for acid leaching. After the acid leaching is completed, the obtained slurry is concentrated and thickened. The concentrated acid leaching underflow enters the CCD washing process, and the concentrated acid leaching liquid enters the extraction process; in the CCD washing process, the obtained washing water is returned to the pre-leaching step of step S1 as a low-copper raffinate, and the obtained washing residue is neutralized and discharged into the tailings pond; in the extraction process, the obtained high-copper raffinate is returned to the acid leaching step, and the extract enters the electrolytic process after stripping to recover copper.

[0017] The beneficial effects of the present invention are:

[0018] (1) The present invention proposes to use low-copper raffinate to pre-soak talc-containing copper-cobalt oxide ore, so as to fully utilize the sulfuric acid in the low-copper raffinate and save the cost of the low-copper raffinate neutralizing agent.

[0019] (2) In order to solve the problems of high acid consumption, mixing of bubbling tank and thickener, increased three-phase extraction, and reduced electrolytic deposition efficiency when talc-containing copper-cobalt oxide ore is directly fed into the leaching system, the present invention proposes a pre-leaching process for talc-containing copper-cobalt oxide ore, which preliminarily decomposes the acid-consuming substances in the talc-containing copper-cobalt oxide ore, reduces the impact of the talc-containing copper-cobalt oxide ore directly entering the leaching system on production, reduces the occurrence of production accidents such as mixing of bubbling tank and thickener, and increased three-phase extraction, and ensures electrolytic deposition efficiency.

[0020] (3) The method of the present invention has the advantage of low production cost, can reduce the break-even grade of copper-cobalt oxide ore, and realize the development of low-grade copper-cobalt oxide ore. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of the methods of Examples 1, 2, and 3 of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings. It should be noted that this embodiment is based on the technical solution and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to this embodiment.

[0023] Example 1

[0024] The talc-containing copper-cobalt oxide ore in this example contains, by mass, 2.93% Cu, 0.12% Co, 4.7% Ca, 7.3% Mg, 2.4% Al, and 2.5% talc. The talc-containing copper-cobalt oxide ore has a particle size of -200 mesh, accounting for 62.5% of the total talc content. The low-copper raffinate contains 0.3 g / L Cu, 1.1 g / L Co, and an acidity of 12.7 g / L.

[0025] This embodiment provides a method for treating a talc-containing copper-cobalt oxide ore, such as Figure 1 As shown, the following steps are included:

[0026] S1. Pre-leaching was performed by mixing a talc-containing copper-cobalt oxide ore with a low-copper raffinate. The pre-leaching temperature was room temperature, the pre-leaching time was 3 hours, the pre-leaching slurry mass concentration was 30%, and the pre-leaching endpoint pH was 4.6. The pre-leaching Cu leaching rate was 45.39%, and the Co leaching rate was 8.32%.

[0027] The main purpose of pre-leaching is to use the sulfuric acid in the low-copper raffinate to react with the talc and other carbonates in the talc-containing copper-cobalt oxide ore, while minimizing the copper leaching rate (reducing the subsequent copper precipitation cost), thereby effectively utilizing the sulfuric acid in the low-copper raffinate, reducing the cost of lime neutralization of the low-copper raffinate, and reducing the leaching acid consumption of the talc-containing copper-cobalt oxide ore entering the original acid leaching system.

[0028] S2. Using a thickener, the preleached slurry obtained after the preleaching in step S1 is subjected to solid-liquid separation to obtain a preleaching underflow and a preleaching supernatant. The copper content of the preleaching underflow is 1.55%, and the copper concentration of the preleaching supernatant is 5.83 g / L.

[0029] S3, adding lime slurry to the pre-leaching supernatant obtained in step S2 to carry out copper precipitation reaction, the copper precipitation reaction end point pH is 5.8, the lime consumption is 8.57kg / m 3 liquid.

[0030] S4. Using a thickener, the copper slurry obtained after the copper precipitation reaction in step S3 is separated into solid and liquid to obtain copper precipitation slag and copper precipitation supernatant. The copper concentration of the copper precipitation supernatant is 0.012 g / L, and the copper content of the copper precipitation slag is 16.08%.

[0031] S5. The copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 and returned to the acid leaching system to further recover copper and cobalt. The acid leaching endpoint pH is 2, and the acid leaching acid consumption is 103.25 kg / t ore ( / t ore refers to the dry weight of the original talc-containing copper-cobalt oxide ore per ton). The copper precipitate supernatant obtained in step S4 is subjected to cobalt precipitation using magnesium oxide to obtain a cobalt hydroxide product.

[0032] In this embodiment, in step S5, the copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 for acid leaching. After the acid leaching is completed, the resulting slurry is concentrated and thickened. The concentrated acid leaching underflow enters the CCD washing process, and the concentrated acid leaching liquid enters the extraction process. In the CCD washing process, the washing water obtained is returned to the pre-leaching step of step S1 as a low-copper raffinate, and the obtained washing residue is neutralized and discharged into the tailings pond. In the extraction process, the obtained high-copper raffinate is returned to the acid leaching step, and the extract enters the electrolytic process after stripping to recover copper.

[0033] Comparative Example 1

[0034] The talc-containing copper-cobalt oxide ore and low-copper raffinate used in this comparative example are the same as those in Example 1. The processing flow is as follows:

[0035] (1) The talc-containing copper-cobalt oxide ore was slurried with water and directly leached with sulfuric acid. The leaching temperature was room temperature, the leaching time was 3 h, the leaching slurry mass concentration was 30%, the leaching endpoint pH was 2, and the leaching acid consumption was 165.89 kg / t ore dry weight.

[0036] (2) The low copper raffinate was directly neutralized with lime slurry. The pH at the end of the reaction was 5.8 and the lime consumption was 14.27 kg / m 3 liquid.

[0037] Example 2

[0038] The talc-containing copper-cobalt oxide ore used in this example contains, by mass, 1.15% Cu, 0.18% Co, 8.5% Ca, 13.1% Mg, 3.8% Al, and 4.7% talc. The talc-containing copper-cobalt oxide ore has a particle size of -200 mesh, accounting for 50% of the total talc content. The low-copper raffinate contains 0.2 g / L Cu, 0.9 g / L Co, and an acidity of 7.2 g / L.

[0039] This embodiment provides a method for treating a talc-containing copper-cobalt oxide ore, such as Figure 1 As shown, the following steps are included:

[0040] S1. Pre-leaching was performed by mixing a talc-containing copper-cobalt oxide ore with a low-copper raffinate. The pre-leaching temperature was room temperature, the pre-leaching time was 2 hours, the pre-leaching slurry concentration was 10%, and the pre-leaching endpoint pH was 4.3. The pre-leaching Cu leaching rate was 32.87%, and the Co leaching rate was 12.55%.

[0041] S2. Using a thickener, the preleached slurry obtained after the preleaching in step S1 is subjected to solid-liquid separation to obtain a preleaching underflow and a preleaching supernatant. The copper content of the preleaching underflow is 0.84%, and the copper concentration of the preleaching supernatant is 1.67 g / L.

[0042] S3, adding lime slurry to the pre-leaching supernatant obtained in step S2 to carry out copper precipitation reaction, the copper precipitation reaction end point pH is 6, the lime consumption is 5.73kg / m 3 liquid.

[0043] S4. Using a thickener, the copper slurry obtained after the copper precipitation reaction in step S3 is subjected to solid-liquid separation to obtain copper precipitation slag and copper precipitation supernatant. The copper concentration of the copper precipitation supernatant is 0.002 g / L, and the copper content of the copper precipitation slag is 14.17%.

[0044] S5. The copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 and returned to the acid leaching system to further recover copper and cobalt. The acid leaching endpoint pH is 2 and the acid consumption is 95.71 kg / t ore. The copper precipitate supernatant obtained in step S4 is subjected to cobalt precipitation using magnesium oxide to obtain a cobalt hydroxide product.

[0045] In this embodiment, in step S5, the copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 for acid leaching. After the acid leaching is completed, the resulting slurry is concentrated and thickened. The concentrated acid leaching underflow enters the CCD washing process, and the concentrated acid leaching liquid enters the extraction process. In the CCD washing process, the washing water obtained is returned to the pre-leaching step of step S1 as a low-copper raffinate, and the obtained washing residue is neutralized and discharged into the tailings pond. In the extraction process, the obtained high-copper raffinate is returned to the acid leaching step, and the extract enters the electrolytic process after stripping to recover copper.

[0046] Comparative Example 2

[0047] The talc-containing copper-cobalt oxide ore and low-copper raffinate used in this comparative example are the same as those in Example 2. The treatment process is as follows:

[0048] (1) The talc-containing copper-cobalt oxide ore was slurried with water and directly leached with sulfuric acid. The leaching temperature was room temperature, the leaching time was 2 h, the leaching slurry concentration was 10%, the leaching end point pH was 2, and the leaching acid consumption was 141.05 kg / t ore dry weight.

[0049] (2) The low copper raffinate was directly neutralized with lime slurry. The pH at the end of the reaction was 6 and the lime consumption was 7.89 kg / m 3 liquid.

[0050] Example 3

[0051] The talc-containing copper-cobalt oxide ore used in this example contains, by mass, 4.88% Cu, 2.98% Co, 3.3% Ca, 8.1% Mg, 5.3% Al, and 6.3% talc. The talc-containing copper-cobalt oxide ore has a particle size of -200 mesh, accounting for 68% of the total talc content. The low-copper raffinate contains 0.1 g / L Cu, 0.9 g / L Co, and an acidity of 15.9 g / L.

[0052] This embodiment provides a method for treating a talc-containing copper-cobalt oxide ore, such as Figure 1 As shown, the following steps are included:

[0053] S1. Pre-leaching was performed by mixing the talc-containing copper-cobalt oxide ore with the low-copper raffinate. The pre-leaching temperature was room temperature, the pre-leaching time was 1 hour, the pre-leaching slurry concentration was 20%, and the pre-leaching endpoint pH was 4.5. The pre-leaching Cu leaching rate was 52.08%, and the Co leaching rate was 15.4%.

[0054] S2. Using a thickener, the preleached slurry obtained after the preleaching in step S1 is subjected to solid-liquid separation to obtain a preleaching underflow and a preleaching supernatant. The copper content of the preleaching underflow is 2.61%, and the copper concentration of the preleaching supernatant is 6.35 g / L.

[0055] S3, adding lime slurry to the pre-leaching supernatant obtained in step S2 to carry out copper precipitation reaction, the copper precipitation reaction end point pH is 6.1, and the lime consumption is 10.32kg / m 3 liquid.

[0056] S4. Using a thickener, the copper precipitate slurry obtained in step S3 is separated into solid and liquid to obtain copper precipitate slag and copper precipitate supernatant. The copper concentration of the copper precipitate supernatant is 0.001 g / L, and the copper content of the copper precipitate slag is 15.38%.

[0057] In step S5, the copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 and returned to the acid leaching system to further recover copper and cobalt. The leaching endpoint pH is 2, and the leaching acid consumption is 156.23 kg / t ore. The copper precipitate supernatant is used to precipitate cobalt using magnesium oxide to obtain a cobalt hydroxide product.

[0058] In this embodiment, in step S5, the copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 for acid leaching. After the acid leaching is completed, the resulting slurry is concentrated and thickened. The concentrated acid leaching underflow enters the CCD washing process, and the concentrated acid leaching liquid enters the extraction process. In the CCD washing process, the washing water obtained is returned to the pre-leaching step of step S1 as a low-copper raffinate, and the obtained washing residue is neutralized and discharged into the tailings pond. In the extraction process, the obtained high-copper raffinate is returned to the acid leaching step, and the extract enters the electrolytic process after stripping to recover copper.

[0059] Comparative Example 3

[0060] The talc-containing copper-cobalt oxide ore and low-copper raffinate used in this comparative example are the same as those in Example 3. The treatment process is as follows:

[0061] (1) The talc-containing copper-cobalt oxide ore was slurried with water and directly leached with sulfuric acid. The leaching temperature was room temperature, the leaching time was 1 h, the leaching slurry concentration was 20%, the leaching end point pH was 2, and the leaching acid consumption was 218.98 kg / t ore dry weight.

[0062] (2) The low copper raffinate was directly neutralized with lime slurry. The pH at the end of the reaction was 6.1 and the lime consumption was 16.42 kg / m 3 liquid.

[0063] The main process technical indicators of the treatment method of the talc-containing copper-cobalt oxide ore used in Examples 1, 2, and 3 and the direct acid leaching process of the talc-containing copper-cobalt oxide ore used in Comparative Examples 1, 2, and 3 are shown in Table 1.

[0064] Table 1

[0065]

[0066] Note: Utilization rate of sulfuric acid of low copper raffinate = (1-pre-soaking end point acidity / pre-soaking initial acidity) × 100%.

[0067] As shown in Table 1, Examples 1-3 can fully utilize the sulfuric acid in the low-copper raffinate, with a sulfuric acid utilization rate of more than 93%. Since the sulfuric acid in the low-copper raffinate is used to pre-soak the talc-containing copper-cobalt oxide ore, the acid leaching acid consumption of Examples 1-3 is reduced by more than 45 kg / t ore compared with Comparative Example 1-3. Moreover, since the sulfuric acid in the low-copper raffinate is basically reacted completely, the neutralization lime consumption is greatly reduced. The neutralization lime consumption of Examples 1-3 is reduced by 2 kg / m 3 liquid or above.

[0068] Those skilled in the art can make various corresponding changes and modifications based on the above technical solutions and concepts, and all of these changes and modifications should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for treating talc-containing copper-cobalt oxide ore, characterized in that: The following steps are involved: S1, mixing the talc-containing copper-cobalt oxide ore with the low-copper raffinate for pre-leaching; S2, using a thickener to perform solid-liquid separation on the preleached slurry obtained after the preleaching in step S1 to obtain a preleached underflow and a preleached supernatant; S3, adding lime slurry to the pre-leaching supernatant obtained in step S2 to carry out copper precipitation reaction; S4, using a thickener to perform solid-liquid separation on the copper precipitation slurry obtained after the copper precipitation reaction in step S3 to obtain copper precipitation residue and copper precipitation supernatant; S5. The copper precipitation residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 and returned to the acid leaching system to further recover copper and cobalt; the copper precipitation supernatant obtained in step S4 is subjected to cobalt precipitation using magnesium oxide to obtain a cobalt hydroxide product.

2. The method according to claim 1, characterized in that In step S1, the talc-containing copper-cobalt oxide ore contains Cu 1-5%, Co 0-5%, Ca 0.5-15%, Mg 0.5-15%, Al 0.5-15%, and talc>0.5% by mass, and the particle size of the talc-containing copper-cobalt oxide ore is -200 mesh, accounting for ≥50% by mass.

3. The method according to claim 1, characterized in that In step S1, the low-copper raffinate contains Cu 0-2 g / L, Co 0-5 g / L, and has an acidity of ≥5 g / L.

4. The method according to claim 1, wherein In step S1, the pre-leaching temperature is room temperature, the pre-leaching time is 0.5-3 hours, the pre-leaching pulp mass concentration is 5%-40%, and the end point pH of the pre-leaching is 4-5.

5. The method according to claim 1, wherein In step S3, the endpoint pH of the copper precipitation reaction is 5.6-6.

2.

6. The method according to claim 1, characterized in that In step S5, the copper precipitate residue obtained in step S4 is mixed with the pre-leaching underflow obtained in step S2 for acid leaching. After the acid leaching is completed, the obtained slurry is concentrated and thickened. The concentrated acid leaching underflow enters the CCD washing process, and the concentrated acid leaching liquid enters the extraction process; in the CCD washing process, the obtained washing water is returned to the pre-leaching step of step S1 as a low-copper raffinate, and the obtained washing residue is neutralized and discharged into the tailings pond; in the extraction process, the obtained high-copper raffinate is returned to the acid leaching step, and the extract enters the electrolytic process after stripping to recover copper.

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