A method for the flotation separation of copper-molybdenum ores

Abstract

This invention discloses a flotation separation method for copper-molybdenum ore. The method includes the following steps: 1) grinding the raw copper-molybdenum ore to obtain a copper-molybdenum slurry. During grinding, a slurry conditioner is added to adjust the pH of the copper-molybdenum slurry to 7.5–9.5 and the potential to 200–300 mV; 2) adding a non-polar collector and a frother to the copper-molybdenum slurry for rough flotation to obtain a flotation concentrate and flotation tailings; the flotation concentrate is then subjected to blank cleaning to obtain a copper-molybdenum mixed concentrate; 3) mixing and grinding the copper-molybdenum mixed concentrate with expanded graphite to obtain a copper-molybdenum mixed concentrate slurry; the copper-molybdenum mixed concentrate slurry is subjected to one roughing and multiple cleaning processes to obtain molybdenum concentrate and copper concentrate I; 4) the flotation tailings are subjected to one roughing and multiple cleaning processes to obtain copper concentrate II. This invention can reduce the impact of lime on copper-molybdenum recovery, greatly improve the flotation recovery rate of copper and molybdenum, and significantly reduce the amount of copper-molybdenum separation inhibitor used, achieving clean and efficient flotation recovery of copper-molybdenum ore.

Description

Technical Field

[0001] This invention relates to the field of mineral flotation processes and reagents, specifically to a flotation separation method for copper-molybdenum ore, belonging to the field of copper-molybdenum ore beneficiation technology. Background Technology

[0002] Molybdenum, as a very important rare metal and strategic reserve resource, possesses excellent electrical conductivity, processing stability, and high-temperature and high-strength properties, finding applications in various fields such as electronics manufacturing, chemicals, metallurgy, national defense, and daily life. Copper, as a strategic metal resource, also has wide applications in new energy, electrical, and electronic fields. Porphyry copper-molybdenum ore is the main source of copper and molybdenum resources. Currently, the flotation recovery of this type of ore mainly adopts two processes: copper-molybdenum mixed flotation—copper-molybdenum separation, or molybdenum-copper and other floatable processes—enhanced copper flotation—copper-molybdenum separation. In the copper-molybdenum mixed flotation or molybdenum-copper and other floatable processes, lime is added as a pyrite inhibitor, and Z200 type polar collectors are used as copper-molybdenum collectors. In the copper-molybdenum separation process, sodium sulfide or sodium hydrosulfide is added to de-process the chalcopyrite surface, and sodium mercaptoacetate is added to inhibit chalcopyrite. However, in actual production, the process and reagent system still have the following major problems: (1) When adding a large amount of lime to the copper-molybdenum mixed flotation or equal floatable operation to suppress pyrite, it also suppresses molybdenite and gold and silver minerals, resulting in low recovery rate of associated metals; (2) Since polar collectors are added during the copper-molybdenum flotation process, the reagents form strong chemical adsorption on the surface of chalcopyrite. Therefore, in the subsequent copper-molybdenum separation operation, a large amount of sodium sulfide or sodium hydrosulfide needs to be added to ensure effective desorption of reagents from the surface of chalcopyrite. This not only results in high cost of copper-molybdenum separation, but also brings about safety and environmental protection problems and water treatment difficulties.

[0003] Therefore, there is an urgent need to invent a clean, efficient, and effective flotation separation method for copper-molybdenum ore to ensure the efficient recovery and utilization of copper-molybdenum resources. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a flotation separation method for copper-molybdenum ore. This method can significantly improve the separation and recovery efficiency of copper and molybdenum, and is simple, low-cost, environmentally friendly, and suitable for industrial application.

[0005] To achieve the above-mentioned technical objectives, the present invention provides a flotation separation method for copper-molybdenum ore. The method includes the following steps:

[0006] 1) Grind the copper-molybdenum ore to obtain copper-molybdenum slurry. During the grinding process, add slurry conditioner to adjust the pH of the copper-molybdenum slurry to 7.5-9.5 and the potential to 200-300mV.

[0007] 2) Add collectors and frothers to the copper-molybdenum slurry for rough flotation to obtain flotation concentrate and flotation tailings; the flotation concentrate is then subjected to blank cleaning to obtain a copper-molybdenum mixed concentrate;

[0008] 3) The copper-molybdenum mixed concentrate is mixed and ground with expanded graphite to obtain a copper-molybdenum mixed concentrate slurry. The copper-molybdenum mixed concentrate slurry is subjected to a first roughing process to obtain a molybdenum rough concentrate and a copper rough concentrate I. The molybdenum rough concentrate is subjected to a cleaning process to obtain a molybdenum concentrate. The copper rough concentrate is subjected to a scavenging process to obtain a copper concentrate I.

[0009] 4) The flotation tailings are processed into copper concentrate II through one roughing and multiple cleaning processes.

[0010] This invention firstly involves grinding copper-molybdenum ore to liberate the copper and molybdenum minerals from the gangue minerals. Then, by adjusting the pH and potential of the mixed copper-molybdenum ore pulp, hydrophobic substances such as elemental sulfur are generated on the surface of chalcopyrite, while hydrophilic substances such as ferric hydroxide are generated on the surface of pyrite. This ensures efficient flotation of chalcopyrite while inhibiting the flotation of pyrite, thus enhancing the flotation separation effect. Secondly, in the roughing flotation process, long-chain hydrocarbon collectors are used instead of traditional polar collectors, which significantly improves selectivity and reduces the flotation of pyrite. Simultaneously, the enhanced hydrophobicity of the chalcopyrite surface due to pulp adjustment further improves the separation of hydrocarbons. The collector forms effective hydrophobic adsorption and hydrogen bond adsorption on the pyrite surface, ensuring the recovery of chalcopyrite and molybdenite. Third, no lime is added during the rough flotation process, effectively avoiding the inhibitory effect of lime on molybdenite and gold and silver minerals, and significantly improving the recovery rate of associated metals. Fourth, since the chalcopyrite surface in the copper-molybdenum mixed concentrate does not chemically adsorb polar collectors, it is easier to desorb them later, which is beneficial to the subsequent copper-molybdenum separation operation. At the same time, the expanded graphite used in this invention has abundant pores and active sites, which can effectively adsorb hydrocarbon oil collectors during the regrinding of the copper-molybdenum mixed concentrate, enhancing the desorption effect of the reagents.

[0011] As a preferred embodiment, the content of the slurry after grinding the copper-molybdenum ore to a fineness of -74μm is 55-75wt%, more preferably 60-70wt%.

[0012] As a preferred embodiment, the pulp conditioner includes a pH adjuster and / or a redox agent.

[0013] As a preferred embodiment, the pH adjuster includes at least one of sodium hydroxide, potassium hydroxide, lime, sodium carbonate, and sodium bicarbonate.

[0014] As a preferred embodiment, the redox agent includes at least one of sodium sulfide, sodium hydrosulfide, sodium metabisulfite, and potassium persulfate.

[0015] As a preferred embodiment, the collector is a long-chain hydrocarbon oil collector.

[0016] As a preferred embodiment, the long-chain hydrocarbon oil collector includes at least one of paraffinic oil, heavy oil, lubricating oil, engine oil, and tar.

[0017] As a preferred embodiment, the foaming agent comprises No. 2 oil and / or methyl isobutyl methanol (MIBC).

[0018] As a preferred embodiment, the amount of collector added relative to the copper-molybdenum ore is 20-80 g / t.

[0019] As a preferred embodiment, the amount of foaming agent added relative to the copper-molybdenum ore is 10-50 g / t.

[0020] As a preferred embodiment, the flotation concentrate is subjected to two blank cleaning processes to obtain a copper-molybdenum mixed concentrate.

[0021] As a preferred embodiment, the amount of expanded graphite added relative to the copper-molybdenum ore is 10-50 g / t.

[0022] As a preferred embodiment, the expanded graphite has a particle size of 10–100 μm.

[0023] As a preferred embodiment, the content of the slurry containing copper-molybdenum mixed concentrate ground to a fineness of -38μm is 60-80wt%.

[0024] As a preferred embodiment, sodium mercaptoacetate is added as a chalcopyrite inhibitor and kerosene as a collector during the roughing process of the copper-molybdenum mixed concentrate slurry.

[0025] As a preferred embodiment, the molybdenum concentrate is subjected to 2 to 5 refining processes, with sodium thioglycolate added as a chalcopyrite inhibitor at each refining process.

[0026] As a preferred embodiment, the copper rough concentrate is subjected to 1 to 3 scavenging processes, with kerosene added as a collector in each scavenging process.

[0027] As a preferred option, in the roughing process of copper-molybdenum mixed concentrate slurry, the amount of sodium mercaptoacetate added relative to the copper-molybdenum ore is 10-50 g / t; and the amount of kerosene added relative to the copper-molybdenum ore is 2-10 g / t.

[0028] As a preferred option, the amount of sodium thioglycolate added during each beneficiation process of molybdenum rough concentrate is 0.01 to 0.25 times the mass of sodium thioglycolate added during the roughing process of copper-molybdenum mixed concentrate slurry.

[0029] As a preferred option, the amount of kerosene added during each scavenging process of copper rough concentrate is 0.1 to 0.5 times the mass of kerosene added during the roughing process of copper-molybdenum mixed concentrate slurry.

[0030] As a preferred embodiment, the roughing and cleaning process of the flotation tailings is as follows: the pH of the flotation tailings is adjusted to 10-12 and a copper collector is added for roughing to obtain copper rough concentrate II and copper rough tailings; the copper rough concentrate II is ground and then cleaned by blank to obtain copper concentrate II; the tailings obtained by scavenging the copper rough tailings are the final flotation tailings.

[0031] As a preferred embodiment, lime is used as a pH adjuster during the roughing process of the flotation tailings. The amount of lime added relative to the copper-molybdenum ore is 500–2000 g / t.

[0032] As a preferred embodiment, the copper collector includes at least one of thiocyanate collectors, xanthate collectors, and pyridine collectors.

[0033] As a preferred embodiment, the amount of copper collector added relative to the copper-molybdenum ore is 10-30 g / t.

[0034] As a preferred method, copper rough concentrate II is ground to a fineness of -38μm with a mineral content of 70-90 wt%, and lime is added during the grinding process. The amount of lime added relative to the copper-molybdenum ore is 50-300 g / t. Adding lime can suppress pyrite and improve flotation separation efficiency.

[0035] As a preferred option, copper crude concentrate II undergoes two blank cleaning processes.

[0036] As a preferred embodiment, the copper tailings are subjected to two scavenging processes, with a copper collector added at each scavenging stage. The amount of copper collector used is 0.1 to 0.5 times the amount used in the roughing process of the copper-molybdenum ore.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The separation and recovery efficiency of copper and molybdenum is high. The molybdenum recovery rate reaches more than 88%, the copper recovery rate reaches more than 90%, the grade of molybdenum concentrate is increased to more than 48%, and the overall grade of copper concentrate is increased to more than 21%.

[0039] (2) Chalcopyrite and pyrite are semiconductor minerals. By adding a pulp conditioner to adjust the pH and potential of the pulp, hydrophobic substances such as elemental sulfur are generated on the surface of chalcopyrite, while hydrophilic substances such as iron hydroxide are generated on the surface of pyrite. This ensures efficient flotation of chalcopyrite and inhibits the flotation of pyrite, thus enhancing the flotation separation effect.

[0040] (3) For floatable (rough flotation) of molybdenum, copper and other minerals, long-chain hydrocarbon collectors are used instead of traditional polar collectors, which can significantly improve selectivity and reduce the floating of pyrite. At the same time, thanks to the enhanced hydrophobicity of chalcopyrite surface brought about by slurry adjustment, the hydrocarbon collectors form effective hydrophobic adsorption and hydrogen bond adsorption on the pyrite surface, ensuring the recovery of chalcopyrite and molybdenite.

[0041] (4) Molybdenum, copper and other floatable processes (rough flotation) do not require the addition of lime, which can effectively avoid the inhibitory effect of lime on molybdenite and gold and silver minerals, and significantly improve the recovery rate of associated metals.

[0042] (5) The chalcopyrite surface in the copper-molybdenum mixed concentrate does not have chemically adsorbed polar collectors, and it is easier to desorb them in the future, which is beneficial to the subsequent copper-molybdenum separation operation.

[0043] (6) Expanded graphite has abundant pores and active sites, which can effectively adsorb hydrocarbon oil collectors during the regrinding of copper-molybdenum mixed concentrate, thus enhancing the desorption effect of the reagents.

[0044] (7) The flotation process and reagent system eliminate the addition of sodium sulfide or sodium hydrosulfide, and at the same time significantly reduce the amount of reagents such as lime and sodium mercaptoacetate added, which is beneficial for the concentrator to control production costs and effectively protect the ecological benefits of the concentrator.

[0045] (8) The separation method is simple, low-cost, green and environmentally friendly, and suitable for industrial applications. Attached Figure Description

[0046] Figure 1 This is a process flow diagram of the closed-circuit test used in the embodiments of the present invention. Detailed Implementation

[0047] The present invention will be further illustrated below with reference to the embodiments, but not in a way that limits the invention.

[0048] Example 1

[0049] The experimental raw material (copper-molybdenum ore) contained 0.46 wt% copper and 0.020 wt% molybdenum. The results of process mineralogical studies showed that the main metallic minerals in the sample were pyrite, chalcopyrite, bornite, and molybdenite.

[0050] The copper-molybdenum ore sample was separated by flotation using a method for separating copper-molybdenum ore provided by this invention. The amount of materials added was based on the copper-molybdenum ore sample. The specific steps are as follows:

[0051] 1) First, grind the ore sample to a fineness of -74μm, accounting for 65%. During grinding, add 200g / t of sodium hydroxide as a pulp conditioner to adjust the pulp pH to 8.0 and the pulp potential Eh to 250mV. After grinding, add 40g / t of heavy oil as a collector and 30g / t of No. 2 oil as a frother for molybdenum and copper equal floatable roughing to obtain equal floatable rough concentrate and equal floatable tailings. The equal floatable rough concentrate is then subjected to two blank cleaning processes to obtain a copper-molybdenum mixed concentrate.

[0052] 2) The copper-molybdenum mixed concentrate was regrinded to a fineness of -38μm (70%). During regrinding, 25 g / t of expanded graphite with a particle size of 50μm was added. Subsequently, 30 g / t of sodium thioglycolate and 5 g / t of kerosene were added for copper-molybdenum separation roughing. The roughing concentrate was then subjected to four cleaning processes. In the first to fourth cleaning processes, 5 g / t, 3 g / t, 2 g / t, and 1 g / t of sodium thioglycolate were added, respectively. The final cleaned concentrate obtained was molybdenum concentrate. The roughing tailings were subjected to two scavenging processes, with 2 g / t of kerosene added in each process. The final scavenged tailings were copper concentrate 1.

[0053] 3) In step (1), 1000 g / t of lime was added to the equally floatable tailings to adjust the pH of the slurry to 10.5, followed by the addition of 20 g / t of Z-200 for roughing. The rough concentrate was regrinded to a fineness of -38 μm (75%), with 200 g / t of lime added during regrinding. Two blank cleaning processes were then performed (without any reagents), yielding copper concentrate 2. The roughing tailings were subjected to two scavenging processes: 10 g / t of Z-200 was added in the first scavenging, and 5 g / t of Z-200 was added in the second scavenging. The scavenged tailings were the final flotation tailings. The separation results are shown in Table 1.

[0054] Table 1

[0055]

[0056]

[0057] The results of this embodiment show that the present invention can obtain a molybdenum concentrate with a molybdenum grade of 49.15% and a molybdenum recovery rate of 88.76%; the copper grade in copper concentrate 1 is 23.89% and the copper recovery rate is 68.39%; the copper grade in copper concentrate 2 is 17.67% and the copper recovery rate is 21.84%; the combined copper grade of copper concentrate 1 and copper concentrate 2 is 22.01% and the copper recovery rate is 90.23%.

[0058] Example 2

[0059] Copper and molybdenum were separated and recovered using the method in Example 1, with the difference being that lime was added as a slurry conditioner during the grinding process of the raw ore to adjust the slurry pH to 8.5 and the slurry potential Eh to 226mV. The results are shown in Table 2.

[0060] Table 2

[0061]

[0062] This embodiment yields a molybdenum concentrate with a molybdenum grade of 50.22% and a molybdenum recovery rate of 88.23%; copper concentrate 1 has a copper grade of 24.13% and a copper recovery rate of 69.83%; copper concentrate 2 has a copper grade of 18.88% and a copper recovery rate of 19.83%; the combined copper grade of copper concentrate 1 and copper concentrate 2 is 22.73%, and the copper recovery rate is 89.66%.

[0063] Example 3

[0064] Copper and molybdenum were separated and recovered using the method in Example 1, with the difference being that sodium sulfide was added as a slurry conditioner during the grinding process of the raw ore to adjust the slurry pH to 9.0 and the slurry potential Eh to 269mV. The results are shown in Table 3.

[0065] Table 3

[0066]

[0067] This embodiment yields a molybdenum concentrate with a molybdenum grade of 48.62% and a molybdenum recovery rate of 89.81%; copper concentrate 1 has a copper grade of 23.26% and a copper recovery rate of 73.80%; copper concentrate 2 has a copper grade of 17.04% and a copper recovery rate of 16.78%; the combined copper grade of copper concentrate 1 and copper concentrate 2 is 21.79%, and the copper recovery rate is 90.57%.

[0068] Example 4

[0069] Copper and molybdenum were separated and recovered using the method of Example 1, with the difference being that the equal floatable coarse separator used paraffin-based oil and machine oil in a mass ratio of 1:1. The results are shown in Table 4.

[0070] Table 4

[0071]

[0072] This embodiment yields a molybdenum concentrate with a molybdenum grade of 48.73% and a molybdenum recovery rate of 89.14%; copper concentrate 1 has a copper grade of 23.49% and a copper recovery rate of 68.86%; copper concentrate 2 has a copper grade of 18.24% and a copper recovery rate of 21.62%; the combined copper grade of copper concentrate 1 and copper concentrate 2 is 21.98%, and the copper recovery rate is 90.49%.

[0073] Example 5

[0074] The experimental raw material (copper-molybdenum ore) contained 0.37 wt% copper and 0.016 wt% molybdenum. The results of process mineralogical studies showed that the main metallic minerals in the sample were pyrite, chalcopyrite, and molybdenite.

[0075] The flotation separation method for copper-molybdenum ore provided by this invention is used to separate the ore sample by flotation. The specific steps are as follows:

[0076] 1) First, grind the ore sample to a fineness of -74μm, with 70% of the sample being fine. During grinding, add 100g / t sodium metabisulfite and 150g / t sodium hydroxide as pulp conditioners to adjust the pulp pH to 7.5 and the pulp potential Eh to 279mV. After grinding, add 30g / t tar as a collector and 30g / t No. 2 oil as a frother for molybdenum-copper co-flotable roughing to obtain co-flotable rough concentrate and co-flotable tailings. The co-flotable rough concentrate is then subjected to two blank cleaning processes to obtain a copper-molybdenum mixed concentrate.

[0077] 2) The copper-molybdenum mixed concentrate was regrinded to a fineness of -38μm (80%). During regrinding, 40 g / t of expanded graphite with a particle size of 80μm was added. Subsequently, 20 g / t of sodium thioglycolate and 8 g / t of kerosene were added for copper-molybdenum separation roughing. The roughing concentrate was then subjected to four cleaning processes. In the first to fourth cleaning processes, 5 g / t, 3 g / t, 2 g / t, and 1 g / t of sodium thioglycolate were added, respectively. The final cleaned concentrate obtained was molybdenum concentrate. The roughing tailings were subjected to two scavenging processes, with 2 g / t of kerosene added in each process. The final scavenged tailings were copper concentrate 1.

[0078] 3) In step (1), 1500 g / t of lime was added to the equally floatable tailings to adjust the pH of the slurry to 11, followed by the addition of 10 g / t of sodium ethyl xanthate for roughing. The rough concentrate was regrinded to a fineness of -38 μm (85%), with 300 g / t of lime added during regrinding. Two blank cleaning processes were then performed, yielding copper concentrate 2. The roughing tailings were then subjected to two scavenging processes: 5 g / t of sodium ethyl xanthate was added in the first scavenging, and 3 g / t of sodium ethyl xanthate was added in the second scavenging. The scavenged tailings were the final flotation tailings. The separation results are shown in Table 5.

[0079] Table 5

[0080]

[0081] This embodiment yields a molybdenum concentrate with a molybdenum grade of 48.42% and a molybdenum recovery rate of 89.77%; copper concentrate 1 has a copper grade of 22.72% and a copper recovery rate of 69.07%; copper concentrate 2 has a copper grade of 20.22% and a copper recovery rate of 20.67%; the combined copper grade of copper concentrate 1 and copper concentrate 2 is 22.09%, and the copper recovery rate is 89.74%.

[0082] Example 6

[0083] The experimental raw material (copper-molybdenum ore) contained 0.32 wt% copper and 0.012 wt% molybdenum. The results of process mineralogical studies showed that the main metallic minerals in the sample were pyrite, chalcopyrite, chalcocite, covellite, and molybdenite.

[0084] The flotation separation method for copper-molybdenum ore provided by this invention is used to separate the ore sample by flotation. The specific steps are as follows:

[0085] 1) First, grind the ore sample to a fineness of -74μm, with 60% of the sample being fine. During grinding, add 50g / t potassium persulfate and 500g / t sodium hydrosulfide as pulp conditioners to adjust the pulp pH to 9.5 and the pulp potential Eh to 214mV. After grinding, add 50g / t of a 1:1 mass ratio heavy oil + lubricating oil combined collector and 30g / t of No. 2 oil as a frother for molybdenum and copper equal floatable roughing to obtain equal floatable rough concentrate and equal floatable tailings. The equal floatable rough concentrate is then subjected to two blank cleaning processes to obtain a copper-molybdenum mixed concentrate.

[0086] 2) The copper-molybdenum mixed concentrate was regrinded to a fineness of -38μm (65%). During regrinding, 20 g / t of expanded graphite with a particle size of 20μm was added. Subsequently, 40 g / t of sodium thioglycolate and 4 g / t of kerosene were added for copper-molybdenum separation roughing. The roughing concentrate was then subjected to four cleaning processes. In the first to fourth cleaning processes, 5 g / t, 3 g / t, 2 g / t, and 1 g / t of sodium thioglycolate were added, respectively. The final cleaned concentrate obtained was molybdenum concentrate. The roughing tailings were subjected to two scavenging processes, with 2 g / t of kerosene added in each process. The final scavenged tailings were copper concentrate 1.

[0087] 3) 2000 g / t of lime was added to the equally floatable tailings obtained in step (1) to adjust the pH of the slurry to 11.8, followed by the addition of 15 g / t of butylammonium black for roughing. The rough concentrate was regrinded to a fineness of -38 μm accounting for 70%, with 200 g / t of lime added during regrinding. Two blank cleaning processes were then performed, and the cleaned concentrate was copper concentrate 2. The roughing tailings were subjected to two scavenging processes. 7 g / t of butylammonium black was added in the first scavenging process, and 3 g / t of butylammonium black was added in the second scavenging process. The scavenged tailings were the final flotation tailings. The separation results are shown in Table 6.

[0088] Table 6

[0089]

[0090] This embodiment yields a molybdenum concentrate with a molybdenum grade of 49.03% and a molybdenum recovery rate of 88.32%; copper concentrate 1 has a copper grade of 23.11% and a copper recovery rate of 68.92%; copper concentrate 2 has a copper grade of 19.51% and a copper recovery rate of 21.31%; the combined copper grade of copper concentrate 1 and copper concentrate 2 is 22.14%, and the copper recovery rate is 90.24%.

[0091] Comparative Example 1

[0092] Copper and molybdenum were separated and recovered using the method in Example 1, except that no slurry modifier was added during the grinding process of the raw ore. The results are shown in Table 7.

[0093] Table 7

[0094]

[0095] Under these comparative conditions, a molybdenum concentrate with a grade of 45.22% and a molybdenum recovery rate of 87.96% was obtained; the copper grade in copper concentrate 1 was 16.73% and the copper recovery rate was 60.20%; the copper grade in copper concentrate 2 was 16.89% and the copper recovery rate was 28.19%; the combined copper grade of copper concentrate 1 and copper concentrate 2 was 16.78% and the copper recovery rate was 88.39%. This result is due to the reduced flotation of copper minerals after removing the pulp potential modifier, while the increased flotation of pyrite led to a significant decrease in concentrate grade and recovery rate.

[0096] Comparative Example 2

[0097] Copper and molybdenum were separated and recovered using the method of Example 1, except that the floatable collector was replaced with Z-200. The results are shown in Table 8.

[0098] Table 8

[0099]

[0100]

[0101] Under these comparative conditions, a molybdenum concentrate with a grade of 38.22% and a molybdenum recovery rate of 78.91% was obtained; the copper grade in copper concentrate 1 was 17.43% and the copper recovery rate was 75.87%; the copper grade in copper concentrate 2 was 17.82% and the copper recovery rate was 13.82%; the combined copper grade of copper concentrate 1 and copper concentrate 2 was 17.49% and the copper recovery rate was 89.70%. This result is due to the increased flotation of pyrite after the isoflurgical collector was changed from long-chain hydrocarbon oil to Z-200, leading to a decrease in the copper concentrate grade. Simultaneously, this resulted in a deterioration in copper-molybdenum separation, an increase in the cross-contamination between the molybdenum concentrate and copper concentrate 1, and a significant reduction in molybdenum recovery rate.

[0102] Comparative Example 3

[0103] Copper and molybdenum were separated and recovered using the method in Example 1, with the difference that expanded graphite was not added during the regrinding of the copper-molybdenum mixed concentrate. The test results are shown in Table 9.

[0104] Table 9

[0105]

[0106] Under these comparative conditions, a molybdenum concentrate with a grade of 35.26% and a molybdenum recovery rate of 86.40% was obtained; the copper grade in copper concentrate 1 was 23.68% and the copper recovery rate was 67.87%; the copper grade in copper concentrate 2 was 17.43% and the copper recovery rate was 21.52%; the combined copper grade of copper concentrate 1 and copper concentrate 2 was 21.80% and the copper recovery rate was 89.39%. This result is due to the incomplete desorption of reagents from the chalcopyrite surface without the addition of expanded graphite, leading to poorer copper-molybdenum separation and a significant decrease in the molybdenum concentrate grade.

[0107] Comparative Example 4

[0108] Copper and molybdenum were separated and recovered using the method in Example 2, with the difference being that 750 g / t of lime was added to adjust the pH of the slurry to 9.5 and the slurry potential Eh to 174 mV. The test results are shown in Table 10.

[0109] Table 10

[0110]

[0111] Under these comparative conditions, a molybdenum concentrate with a grade of 48.22% and a molybdenum recovery rate of 89.14% was obtained; the copper grade in copper concentrate 1 was 22.05% and the copper recovery rate was 64.93%; the copper grade in copper concentrate 2 was 15.32% and the copper recovery rate was 22.05%; the combined copper grade of copper concentrate 1 and copper concentrate 2 was 19.84% and the copper recovery rate was 86.98%. This result indicates that the slurry potential was not adjusted, leading to a weakened difference in hydrophobicity between the surfaces of chalcopyrite and pyrite, which reduced the grade and recovery rate of the copper concentrate.

Claims

1. A method for the flotation separation of copper-molybdenum ores, characterized in that: The method comprises the following steps: 1) grinding the copper-molybdenum raw ore to obtain a copper-molybdenum ore slurry, wherein a slurry adjusting agent is added to adjust the pH value of the copper-molybdenum ore slurry to 7.5-9.5 and the electric potential to 200-300 mV during the grinding process; 2) adding a long-chain hydrocarbon oil collector and a foaming agent to the copper-molybdenum ore slurry to perform rough flotation to obtain a flotation concentrate and a flotation tailing; the flotation concentrate is subjected to blank concentration to obtain a copper-molybdenum mixed concentrate; 3) mixing and grinding the copper-molybdenum mixed concentrate with expanded graphite to obtain a copper-molybdenum mixed concentrate slurry, which is subjected to one-time rough concentration to obtain a molybdenum rough concentrate and a copper rough concentrate I; the molybdenum rough concentrate is subjected to concentration to obtain a molybdenum concentrate; the copper rough concentrate is subjected to scavenging to obtain a copper concentrate I; 4) the flotation tailing is subjected to one-time rough concentration and multiple concentration to obtain a copper concentrate II. The sodium mercaptoacetate is added as a chalcopyrite inhibitor and kerosene is added as a collector during the rough concentration of the copper-molybdenum mixed concentrate slurry; wherein the addition amount of the sodium mercaptoacetate relative to the copper-molybdenum raw ore is 10-50 g / t, and the addition amount of the kerosene relative to the copper-molybdenum raw ore is 2-10 g / t.

2. A process for the flotation separation of copper-molybdenum ores as claimed in claim 1, characterized in that: The copper-molybdenum raw ore is ground to a fineness of 55-75 wt% of -74 μm slurry content.

3. A process for the flotation separation of copper-molybdenum ores according to claim 1 or 2, characterized in that: The slurry adjusting agent comprises a pH adjusting agent and / or an oxidation-reduction agent.

4. The method according to claim 3, wherein: the pH adjusting agent comprises at least one of sodium hydroxide, potassium hydroxide, lime, sodium carbonate and sodium bicarbonate; the oxidation-reduction agent comprises at least one of sodium sulfide, sodium hydrosulfide, sodium metabisulfite and potassium peroxodisulfate.

5. The method according to claim 1, wherein: the long-chain hydrocarbon oil collector comprises at least one of paraffin-based oil, heavy oil, lubricating oil, engine oil and tar; the foaming agent comprises 2# oil and / or methyl isobutyl carbinol; the addition amount of the collector relative to the copper-molybdenum raw ore is 20-80 g / t; the addition amount of the foaming agent relative to the copper-molybdenum raw ore is 10-50 g / t.

6. A process for the flotation separation of copper-molybdenum ores as claimed in claim 1, wherein: the addition amount of the expanded graphite relative to the copper-molybdenum raw ore is 10-50 g / t; and the copper-molybdenum mixed concentrate is ground to a fineness of 60-80 wt% of -38 μm slurry content.

7. The method according to claim 1 or 6, wherein: the molybdenum rough concentrate is subjected to 2-5 times of concentration, and sodium mercaptoacetate is added as a chalcopyrite inhibitor during each concentration; the copper rough concentrate is subjected to 1-3 times of scavenging, and kerosene is added as a collector during each scavenging.

8. The method according to claim 7, wherein: during each concentration of the molybdenum rough concentrate, the addition amount of the sodium mercaptoacetate is 0.01-0.25 times of the mass of the sodium mercaptoacetate added during the rough concentration of the copper-molybdenum mixed concentrate slurry; during each scavenging of the copper rough concentrate, the addition amount of the kerosene is 0.1-0.5 times of the mass of the kerosene added during the rough concentration of the copper-molybdenum mixed concentrate slurry.

9. A process for the flotation separation of copper-molybdenum ores as claimed in claim 1, wherein: The roughing and cleaning process of the flotation tailings is: roughing is carried out after adjusting the pH of the flotation tailings to 10-12 and adding a copper collector to obtain a copper rough concentrate II; the copper rough concentrate II is ground and then cleaned by blank cleaning to obtain a copper concentrate II.

10. The method according to claim 9, characterized in that: The copper collector comprises at least one of a sulfidamine collector, a xanthate collector and a black drug collector. The addition amount of the copper collector relative to the copper-molybdenum ore is 10-30 g / t.

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