A copper-molybdenum smelting slag multi-metal collaborative recovery method based on composite conditioning and external field strengthening

Abstract

The application provides a copper-molybdenum smelting slag multi-metal collaborative recovery method based on composite conditioning and external field strengthening, and relates to the field of comprehensive utilization of non-ferrous metal secondary resources. The method comprises the following steps: mixing liquid copper-molybdenum slag and a composite conditioning agent to obtain a mixture; in low-frequency alternating electromagnetic field strengthening treatment, the mixture is subjected to smelting reaction to obtain flue gas, molten slag and matte phase droplets; the matte phase droplets are cooled and ground to obtain ground matte phase; under alkaline conditions, a'mixed roughing- asynchronous separation' process is adopted, the ground matte phase and a collector are mixed for roughing to obtain copper-molybdenum mixed rough concentrate; the copper-molybdenum mixed rough concentrate and an inhibitor are mixed for cleaning to obtain copper concentrate and molybdenum concentrate, and finally, the copper recovery rate is greater than or equal to 92%, the molybdenum recovery rate is greater than or equal to 95%, and the smelting slag is deeply depleted and harmlessly disposed.

Description

Technical Field

[0001] This application relates to the field of comprehensive utilization of secondary non-ferrous metal resources, and in particular to a method for the synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement. Background Technology

[0002] Copper smelting primarily utilizes pyrometallurgical processes to process copper concentrate, generating approximately 2-3 tons of smelting slag for every ton of copper produced. The copper content in this slag typically ranges from 0.5% to 3%, far exceeding the average mineable grade of copper mines in my country (approximately 0.3%). Furthermore, due to the associated characteristics of the ore, the slag is often rich in valuable metals such as molybdenum (0.1%-0.5%), lead (0.1%-1.5%), and zinc (0.5%-2%). Direct stockpiling of these slags not only wastes strategic metal resources but also causes long-term damage to the ecological environment due to the heavy metals and acidic substances they contain, which can leach into soil and water bodies.

[0003] Currently, the industry generally uses the direct slow cooling-flotation process to recover copper sulfide and metallic copper from the slag separately. However, the recovery efficiency for elements such as molybdenum, lead, and zinc is low (generally not exceeding 20%). The main reasons include: 1. The occurrence state of valuable elements is complex. Molybdenum is mostly dispersed in the fritillary phase as molybdenum oxide or isomorphous form, while lead and zinc easily form microcrystalline inclusions with silicates, which are difficult to dissociate through conventional crushing; 2. Molybdenum minerals have strong hydrophilicity, and lead and zinc minerals have fine particle sizes (mostly <10μm), which are easily lost to tailings in the flotation system; 3. Slag component interference effect: Magnetite, glass phase and other components in the slag adsorb the collector, which intensifies the competition and inhibition between valuable element minerals.

[0004] Existing technologies such as wet leaching (acid / alkali system) can partially dissolve valuable metals, but they face problems such as high reagent consumption, severe co-dissolution of impurities (such as iron and arsenic), and high subsequent separation costs. Therefore, developing an efficient, low-cost, and environmentally friendly multi-metal recovery technology from copper smelting slag has become an urgent need to improve the resource efficiency and environmental compliance of copper smelting enterprises. Summary of the Invention

[0005] The purpose of this application is to provide a method for the synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement, so as to solve the above-mentioned problems.

[0006] To achieve the above objectives, this application provides a method for the synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement, comprising: Liquid copper-molybdenum slag and composite conditioning agent are mixed to obtain a mixture; in the process of strengthening treatment by applying a low-frequency alternating electromagnetic field, the mixture is subjected to a smelting reaction, so that the copper and molybdenum components in the liquid copper-molybdenum slag combine with the released active sulfur to generate copper matte droplets and molybdenum matte droplets in situ, and lead and zinc volatilize into the gas phase, resulting in lead-zinc containing flue gas, slag and matte droplets; The matte droplets are cooled and ground to obtain ground matte; under alkaline conditions, the ground matte is mixed with a collector and roughed to obtain a copper-molybdenum mixed rough concentrate; the copper-molybdenum mixed rough concentrate is mixed with an inhibitor and fined to obtain copper concentrate and molybdenum concentrate.

[0007] Optionally, the composite conditioning agent includes a core and a coating layer disposed on the core; the core includes a vulcanizing component, and the coating layer includes a reducing component; The sulfiding component includes at least one of pyrite, gypsum, copper sulfide ore, and sulfate minerals; the reducing component includes at least one of coal, coke, and carbonaceous binder.

[0008] Optionally, the mass ratio of the reducing component to the sulfurizing component is 1:2-7; And / or, the particle size of the composite conditioning agent is 3mm-8mm.

[0009] Optionally, the mass ratio of the liquid copper-molybdenum slag to the composite conditioning agent is 1:0.05-0.2.

[0010] Optionally, the reaction temperature is 1200-1500℃ and the time is 45-180 min; And / or, the volume ratio of CO to CO2 during the reaction is 0.4-1:1; And / or, the flue gas contains lead, zinc or their oxides or sulfides.

[0011] Optionally, the frequency of the low-frequency alternating electromagnetic field enhancement treatment is 0.5 Hz-10 Hz, and the magnetic induction intensity at the center is 50 mT-300 mT.

[0012] Optionally, during the cooling process, the average cooling rate from 1100°C to 800°C is less than 15°C / h; And / or, the mass content of particles with a particle size of less than or equal to 0.074 mm in the ground matte phase is ≥90%.

[0013] Optionally, the collector includes at least one of butyl xanthate, isopentyl xanthate, and butylammonium black powder; And / or, the inhibitor includes at least one of sodium sulfide, sodium hydrosulfide, and Knox pharmaceuticals.

[0014] Optionally, the mass ratio of the collector to the milled matte phase is 0.0005-0.002:1; And / or, the mass ratio of the inhibitor to the milled matte phase is 0.003-0.015:1.

[0015] Optionally, the pH of the coarse selection is 8.5-12.0.

[0016] Compared with the prior art, the beneficial effects of this application include: This application provides a multi-metal synergistic recovery method for copper-molybdenum smelting slag based on composite conditioning and external field enhancement. In high-temperature liquid slag, it utilizes the preferential reaction of reducing components in the composite conditioning agent coating layer to construct localized reducing microregions. Under controlled conditions of CO / CO2 volume ratio and residence time, it simultaneously achieves lead-zinc volatilization recovery, arsenic lattice solidification, and in-situ sulfidation capture of copper-molybdenum components. Furthermore, it introduces a 0.5 Hz-10 Hz magnetic field with a central magnetic induction intensity of 50 mT-300... The low-frequency alternating electromagnetic field of mT drives the directional aggregation and forced sedimentation of fine matte phase droplets, effectively overcoming the high viscosity resistance of the slag system. After slow cooling and fine grinding, the enriched matte phase is then separated and high-purity copper concentrate and molybdenum concentrate are produced by a "mixed roughing-asynchronous separation" process, ultimately achieving a copper recovery rate of ≥92%, a molybdenum recovery rate of ≥95%, and deep depletion and harmless disposal of smelting slag. This application solves the technical problems of difficult sedimentation of fine metal droplets and severe copper-molybdenum intermingling in existing processes through the synergistic effect of core-shell structure composite conditioning agent and low-frequency alternating electromagnetic field enhanced treatment. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation on the scope of this application.

[0018] Figure 1 A photograph of a solid block with a black slag upper layer and a white matte phase lower layer, as provided in Example 1; Figure 2 A physical image of the copper concentrate provided in Example 1; Figure 3 This is a physical image of the molybdenum concentrate provided in Example 1. Detailed Implementation

[0019] First, the solution provided in this application will be explained in more detail as follows: This application provides a method for the synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement, including: Liquid copper-molybdenum slag and composite conditioning agent are mixed to obtain a mixture; in the low-frequency alternating electromagnetic strengthening auxiliary treatment, the mixture is smelted to react, so that the copper and molybdenum components in the liquid copper-molybdenum slag combine with the released active sulfur to generate copper matte droplets and molybdenum matte droplets in situ, and lead and zinc volatilize into the gas phase to obtain lead-zinc containing flue gas, slag and matte droplets; It is important to note that during the reaction process, the lead and zinc oxides in the liquid copper-molybdenum slag are reduced to metal vapor or low-valence oxides, which then volatilize into the flue gas; the volatilization of arsenic in the liquid copper-molybdenum slag is suppressed, and it is stabilized and solidified in the silicate lattice of the molten slag; the copper and molybdenum components in the liquid copper-molybdenum slag combine with the released active sulfur to generate suspended copper matte droplets and molybdenum matte droplets in situ. The reducing components in the composite conditioning agent coating layer contact the molten slag, creating a locally reducing micro-atmosphere around the particles. Under these conditions, lead and zinc oxides (PbO, ZnO) are preferentially reduced because their standard Gibbs free energy is significantly higher than that of iron and silicon oxides at high temperatures. During the reaction, zinc silicate and lead oxide in the slag are reduced by the reducing agent to elemental zinc vapor and elemental lead or its low-valence volatile oxides. Simultaneously, the system precisely controls the oxygen potential by adjusting the CO / CO2 volume ratio within the range of 0.4-1:1, allowing arsenic atoms to partially replace silicon atoms in the slag, forming an arsenic-containing silicate network structure. This network is then stably solidified within the silicate lattice of the molten slag, effectively suppressing secondary arsenic pollution. As the coating layer is consumed, the quencher core releases active sulfur. Based on the order of sulfur affinity (Mo>Cu>Pb / Zn>Fe), dissolved copper (Cu₂O) and molybdenum oxide (MoO₃) in the slag preferentially undergo displacement reactions with the active sulfur, generating stable Cu₂S and MoS₂. The generated sulfide phases fuse together to form suspended copper-molybdenum matte droplets. During the smelting reaction stage, this application introduces a low-frequency alternating electromagnetic field. Under the action of the electromagnetic field, due to the significant difference in conductivity between the matte droplets and the molten slag, the magnetic field generates a directional Lorentz force within the melt, driving the droplets to collide and coalesce. The coalesced large droplets, under the combined action of gravity and electromagnetic driving force, overcome the high viscosity resistance of the high-temperature slag and rapidly settle to the bottom of the furnace, forming an enriched matte layer. It should also be noted that during the reaction process, a controllable electromagnetic field is applied. Utilizing the difference in conductivity between copper matte droplets and molybdenum matte droplets and the slag matrix, and the difference in conductivity between the matte phase (high conductivity) and the slag (low conductivity), a vertically downward electromagnetic volume force is generated within the melt through a magnetic field, thereby strengthening the melt as follows: Directional aggregation: Electromagnetic force is used to drive the fine matte phase droplets suspended in molten slag to migrate directionally relative to the slag matrix, increasing the collision frequency between droplets and promoting their mutual adsorption and aggregation growth; Forced settling: The gravity effect of the aggregated large droplets is combined with the vertically downward electromagnetic driving force to overcome the high viscosity resistance of the high-silicon molten slag and accelerate the settling of matte droplets towards the bottom of the furnace. Flow field stabilization: By controlling the frequency in the low-frequency range, the magnetic field penetration depth is ensured while the severe macroscopic turbulence that is not conducive to sedimentation in the slag matrix is ​​suppressed, providing a stable flow environment for matte slag separation. This effectively overcomes the physical hindrance effect of high-viscosity slag system on fine metal droplets, and achieves efficient enrichment and separation of copper and molybdenum components. The matte droplets are cooled and ground to obtain ground matte; under alkaline conditions, the ground matte is mixed with a collector and roughed to obtain a copper-molybdenum mixed rough concentrate. It should be noted that roughing also yields tailings, which contain iron oxides and silicate gangue. Roughing can separate the iron oxides and silicate gangue from the copper-molybdenum mixed rough concentrate. The copper-molybdenum mixed crude concentrate and the inhibitor are mixed and then finely selected to obtain copper concentrate and molybdenum concentrate.

[0020] In some embodiments, the composite conditioning agent includes a core and a coating layer disposed on the core; the core includes a vulcanizing component, and the coating layer includes a reducing component; The sulfiding component includes at least one of pyrite, gypsum, copper sulfide ore, and sulfate minerals; the reducing component includes at least one of coal, coke, and carbonaceous binder.

[0021] It should be noted that the reducing components in the coating layer of the composite conditioning agent preferentially react with oxides in the slag and ambient oxygen to create a local reducing micro-atmosphere around the particles, protecting the internally wrapped sulfide components from decomposition and release of active sulfur. This core-shell structure with "internal sulfur and external sulfur" has the following technological advantages: Spatiotemporal sequence control: This facilitates the achievement of a kinetic sequence of "reduction and impurity removal first, followed by sulfidation enrichment." The coating layer is consumed first, ensuring that lead-zinc volatilization and magnetic iron reduction are essentially completed before the sulfidation reaction, thus avoiding the ineffective consumption of sulfur components by impurity metals.

[0022] Constructing localized low-oxygen potential micro-regions: The reduction layer generates an oxygen potential environment around the particles that is lower than that of the macroscopic slurry, which protects the internal sulfidation components from being absorbed by high-valent iron (Fe) in the slag. 3+ Direct oxidation greatly improves the utilization rate of active sulfur.

[0023] Reducing slag viscosity: The coating layer preferentially reduces Fe3O4, converting it into FeO, thereby breaking the spinel structure and pre-reducing the viscosity resistance of droplet movement before the sulfidation reaction occurs. This design ensures that the core sulfidation component only begins to release active sulfur after impurity metals such as lead and zinc have completed reduction and volatilization, avoiding the ineffective consumption of sulfur elements and greatly improving the selectivity and utilization rate of copper and molybdenum sulfidation capture.

[0024] In some embodiments, the mass ratio of the reducing component to the sulfurizing component is 1:2-7; Optionally, the mass ratio of the reducing component to the sulfurizing component can be any value between 1:2, 1:3, 1:4, 1:5, 1:6, 1:7 or 1:2-7; It is important to note that this ratio is based on a thermodynamic balance calculation of the amount of carbon required for the reduction of magnetic iron oxide (Fe3O4) in the slag and the amount of sulfur required for the in-situ sulfidation of copper and molybdenum. This range ensures sufficient reduction kinetics to maintain the low viscosity of the slag while avoiding the precipitation of metallic iron (Fe) due to excess carbon. An appropriate ratio can maintain stable oxygen potential in the system, maximize the efficiency of copper-molybdenum sulfidation, and prevent flotation difficulties caused by excessive iron content in the matte phase; and / or, the particle size of the composite conditioning agent is 3mm-8mm.

[0025] Optionally, the particle size of the composite conditioning agent can be any value between 3mm, 4mm, 5mm, 6mm, 7mm, 8mm or 3mm-8mm.

[0026] It is important to note that particle size directly affects the survival time and diffusion efficiency of the reagent in the high-temperature melt. If the particle size is less than 3 mm, the reagent will become ineffective due to excessively rapid reaction or being carried away by flue gas, and the core-shell structure will be difficult to maintain at high temperatures. If the particle size is greater than 8 mm, the contact surface area between the reagent and the molten slag is too small, resulting in an excessively long reaction cycle, and the core sulfurizing component will be difficult to release completely within a limited time. This particle size range ensures that the reagent can stably sink into the interior of the melt and continue to act.

[0027] In some embodiments, the mass ratio of the liquid copper-molybdenum slag to the composite conditioning agent is 1:0.05-0.2. Optionally, the mass ratio of the liquid copper-molybdenum slag to the composite conditioning agent can be any value between 1:0.05, 1:0.1, 1:0.15, 1:0.2, or 1:0.05-0.2.

[0028] In some embodiments, the reaction temperature is 1200-1500°C and the time is 45-180 min; Optionally, the reaction temperature can be any value between 1200℃, 1300℃, 1400℃, 1500℃ or 1200-1500℃, and the time can be any value between 45min, 60min, 90min, 120min, 150min, 180min or 45-180min. And / or, the volume ratio of CO to CO2 during the reaction is 0.4-1:1; Optionally, the volume ratio of CO to CO2 during the reaction can be any value between 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, or 0.4:1; It is important to note that within this ratio range, the system oxygen potential is sufficient to support the reduction and volatilization of lead and zinc oxides, while simultaneously driving arsenic into the silicate phase for lattice solidification. Furthermore, this ratio ensures that Fe3O4 is reduced to FeO, maintaining a low slag viscosity and thus increasing the settling rate of the matte droplets.

[0029] And / or, the flue gas contains lead, zinc or their oxides or sulfides.

[0030] In some embodiments, the frequency of the low-frequency alternating electromagnetic field enhancement treatment is 0.5 Hz-10 Hz, and the magnetic induction intensity at the center is 50 mT-300 mT.

[0031] Optionally, the frequency of the electromagnetic strengthening treatment can be any value between 0.5 Hz, 1 Hz, 2 Hz, 4 Hz, 6 Hz, 8 Hz, 10 Hz or 0.5 Hz-10 Hz, and the magnetic induction intensity at the center can be any value between 50 mT, 100 mT, 150 mT, 200 mT, 250 mT, 300 mT or 50-300 mT.

[0032] It is important to note that the low frequency (0.5-10 Hz) is used to utilize the strong penetration depth of the electromagnetic field to act on the deep melt. The magnetic induction intensity (50-300 mT) is used to generate sufficient Lorentz force. This combination of frequencies can produce significant magnetohydrodynamic effects without inducing severe turbulence, increasing the collision frequency of microdroplets by 2-3 times and the forced settling velocity by two orders of magnitude compared to gravity settling, thus greatly shortening the depletion cycle of the smelting slag. In some embodiments, during the cooling crystallization process, the average cooling rate from 1100°C to 800°C is less than 15°C / h. Optionally, the average cooling rate when cooling from 1100°C to 800°C can be any value of 1°C / h, 5°C / h, 10°C / h, 14°C / h or less than 15°C / h; It should be noted that during the cooling process, the average cooling rate from 1100℃ to 800℃ is less than 15℃ / h, which can induce sufficient growth of copper sulfide and molybdenum sulfide grains. And / or, the mass content of particles with a particle size of less than or equal to 0.074 mm in the ground matte phase is ≥90%.

[0033] It should be noted that grinding can achieve the individual dissociation of useful minerals from gangue and iron oxides; Optionally, the mass content of particles with a particle size of less than or equal to 0.074 mm in the matte phase after grinding can be any value of 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 100%, or ≥90%.

[0034] In some embodiments, the collector includes at least one of butyl xanthate, isopentyl xanthate, and butylammonium black powder; It is important to note that these three types are typical strong collectors for sulfide minerals. Among them, xanthates are the most stable in a weakly alkaline environment with a pH of 8.5-11.

[0035] And / or, the inhibitor includes at least one of sodium sulfide, sodium hydrosulfide, and Knox pharmaceuticals.

[0036] In some embodiments, the mass ratio of the collector to the milled matte phase is 0.0005-0.002:1; Optionally, the mass ratio of the collector to the ground matte phase can be any value between 0.0005:1, 0.001:1, 0.002:1, or 0.0005:0.002:1. And / or, the mass ratio of the inhibitor to the milled matte phase is 0.003-0.015:1.

[0037] Optionally, the mass ratio of the inhibitor to the ground matte phase can be any value between 0.003:1, 0.005:1, 0.01:1, 0.015:1, or 0.003:0.015:1.

[0038] In some embodiments, the pH for coarse selection is 8.5-12.0. Optionally, the pH for coarse selection can be 8.5, 9, 10, 11, 12, or any value between 8.5 and 12.

[0039] The implementation schemes of this application will be described in detail below with reference to specific embodiments. However, those skilled in the art will understand that the following embodiments are only for illustrating this application and should not be regarded as limiting the scope of this application. Unless otherwise specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments used without specified manufacturers are all conventional products that can be purchased commercially.

[0040] Example 1 This application provides a method for the synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement. The specific steps are as follows: The raw material is copper-molybdenum slag containing 2.38% copper, 0.34% molybdenum, 44.14% iron, 0.24% lead, 1.14% zinc, and 28.21% silicon.

[0041] S1: A composite conditioning agent is provided, including a core and a coating layer disposed in the core; the core includes a sulfide component (pyrite), the coating layer includes a reducing component (coke and binder), the mass ratio of the reducing component and the sulfide component is 1:5, and the particle size of the composite conditioning agent is 5mm. S2: A mixture is obtained by mixing liquid copper-molybdenum slag and composite conditioning agent, with a mass ratio of liquid copper-molybdenum slag to composite conditioning agent of 1:0.1; S3: The mixture is added to the reaction apparatus, and a controllable low-frequency alternating electromagnetic field is applied externally to enhance the reaction. The temperature of the reactants is maintained at 1350℃, the residence time is 120 minutes, the volume ratio of CO to CO2 during the reaction is 0.6:1, and the frequency of the electromagnetic field is controlled at 2Hz, the central magnetic induction intensity is 150mT. After the reaction, flue gas, slag, and matte droplets are obtained. In the S3 electromagnetic enhancement stage, the conductivity difference between the matte droplets and the slag is approximately 10 times that of the slag. 3 -10 4 The low-frequency alternating electromagnetic field generates a vertically downward Lorentz force (F=J×B) inside the melt, which drives the droplet collision frequency to increase by 2-3 times compared with the condition without electromagnetic field, and the sedimentation rate to increase by about two orders of magnitude compared with simple gravity sedimentation. S4: The mixture of molten slag and matte droplets is cooled and crystallized. The average cooling rate of the matte droplets in the critical temperature range of 1100℃ to 800℃ is controlled at 10℃ / h. After slow cooling, a solid block is obtained with a black molten slag upper layer and a white matte phase (copper-sulfur mixture) lower layer, as shown in the figure. Figure 1 As shown, the upper and lower layers are separated, and the lower layer material is subjected to multi-stage fine grinding to control the mass content of particles with a particle size of less than or equal to 0.074 mm in the matte phase after grinding to be ≥90%. S5: Under alkaline conditions, the ground matte phase and collector (butyl xanthate) are mixed for roughing. The mass ratio of collector to ground matte phase is 0.001:1 to obtain a copper-molybdenum mixed rough concentrate. S6: The copper-molybdenum mixed crude concentrate and the inhibitor (sodium sulfide) are mixed and finely treated. The mass ratio of the inhibitor to the matte phase after grinding is 0.01:1, yielding copper concentrate and molybdenum concentrate. A photograph of the copper concentrate is shown below. Figure 2 As shown in the photograph, the actual product of molybdenum concentrate is as follows: Figure 3 As shown.

[0042] The final technical targets achieved were a copper recovery rate of 93.20% and a molybdenum recovery rate of 96.35%.

[0043] Example 2 The difference from Example 1 is that the composite conditioning agent is different. The core of the composite conditioning agent provided in this example includes a sulfidation component (gypsum and sulfate minerals), and the coating layer includes a reducing component (coke and binder). The mass ratio of the reducing component to the sulfidation component is 1:5, and the particle size of the composite conditioning agent is 8 mm.

[0044] Example 2 also demonstrated excellent multi-metal recovery performance. In the final product, the copper recovery rate reached 94.23%, and the molybdenum recovery rate was as high as 97.5%.

[0045] Example 3 The difference from Example 1 is that the amount of composite conditioning agent is different. In this example, the mass ratio of liquid copper-molybdenum slag to composite conditioning agent is 1:0.05.

[0046] When the amount of conditioning agent added was reduced to 5%, the various indicators fluctuated slightly, but still remained within the high-efficiency recovery range. The copper recovery rate was 90.5%, and the molybdenum recovery rate was 92.8%.

[0047] Comparative Example 1 The difference from Example 1 is that no composite conditioning agent is added.

[0048] Comparative Example 2 The difference from Example 1 is that the composite conditioning agent only contains an equal mass of vulcanizing components and does not contain a reducing component for the coating layer.

[0049] Comparative Example 3 The difference from Example 1 is that the composite conditioning agent only contains an equal mass of reducing components, specifically coke.

[0050] Comparative Example 4 The difference from Example 1 is that no low-frequency alternating electromagnetic field enhancement treatment was applied during the reaction process. Relying on natural sedimentation under gravity, the separation interface between the matte phase and the slag phase became relatively blurred. A large number of copper-molybdenum particles with a diameter less than 10 μm remained in the slag layer.

[0051] Comparative Example 5 The difference from Example 1 is that after the reaction process, the matte droplets were directly and rapidly cooled in the furnace at a rate of 50°C / h, close to that of normal air cooling. Due to the excessively rapid cooling rate, copper and molybdenum grains could not effectively aggregate and grow, resulting in a monomer liberation degree of only 42% after grinding. Consequently, the flotation indicators decreased significantly, with the copper concentrate grade dropping to 11.20% and the copper recovery rate decreasing to 74.50%, thus verifying the role of the slow cooling process in improving the beneficiation grade.

[0052] The recovery rates of copper and molybdenum prepared in the above embodiments and comparative examples, as well as the grades of copper concentrate and molybdenum concentrate, are shown in Table 1.

[0053] Table 1 Recovery rate and grade

[0054] analyze: As can be seen from the above tests, the multi-metal synergistic recovery method for copper and molybdenum smelting slag based on composite conditioning and external field enhancement provided in this application significantly improves the comprehensive recovery effect of copper and molybdenum while achieving efficient volatilization and separation of lead and zinc through the synergistic combination of core-shell structure composite conditioning agent, low-frequency alternating electromagnetic field and controlled slow cooling process.

[0055] The comparative data fully demonstrates the necessity of each key technical step: 1. The core-shell structure of the composite conditioning agent, through the time-series control mechanism of "internal sulfur and external reduction," enables the reducing components to preferentially construct local low-oxygen potential micro-regions around the particles, effectively protecting the core sulfidation components from ineffective oxidation loss, thereby ensuring the selectivity and efficiency of in-situ sulfidation enrichment of copper and molybdenum; 2. The application of a low-frequency alternating electromagnetic field utilizes the difference in conductivity between the matte phase and the slag matrix, driving the directional aggregation and forced sedimentation of fine matte phase droplets through magnetohydrodynamic effects, thus improving the droplet sedimentation kinetic rate compared to simple gravity sedimentation, breaking through the physical bottleneck of the difficulty in effectively separating fine droplets in high-viscosity slag systems; 3. The controlled slow cooling process, by controlling the cooling rate of the key temperature zone below 15℃ / h, induces the full growth of copper and molybdenum sulfide grains, laying the mineralogical foundation for subsequent fine grinding, dissociation, and flotation separation.

[0056] This application provides a systematic technical solution for the multi-metal synergistic recovery and green utilization of complex copper-molybdenum smelting slag.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

[0058] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, any of the claimed embodiments can be used in any combination. The information disclosed in this background section is intended only to enhance the understanding of the general background of this application and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

Claims

1. A method for synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement, characterized in that, include: Liquid copper-molybdenum smelting slag and composite conditioning agent are mixed to obtain a mixture; in the process of strengthening treatment by applying a low-frequency alternating electromagnetic field, the mixture is subjected to a smelting reaction, so that the copper and molybdenum components in the liquid copper-molybdenum smelting slag combine with the released active sulfur to generate copper matte droplets and molybdenum matte droplets in situ, and lead and zinc volatilize into the gas phase, resulting in lead-zinc containing flue gas, slag and matte droplets; The matte droplets are cooled and ground to obtain ground matte. Under alkaline conditions, the ground matte phase and collector are mixed and roughed to obtain a copper-molybdenum mixed rough concentrate; the copper-molybdenum mixed rough concentrate is mixed with an inhibitor and fined to obtain copper concentrate and molybdenum concentrate. The composite conditioning agent includes a core and a coating layer disposed on the core; the core includes a vulcanizing component, and the coating layer includes a reducing component; The sulfiding component includes at least one of pyrite, gypsum, copper sulfide ore, and sulfate minerals; the reducing component includes at least one of coal, coke, and carbonaceous binder. The volume ratio of CO to CO2 in the reaction process is 0.4-1:1; The frequency of the low-frequency alternating electromagnetic field enhancement treatment is 0.5 Hz-10 Hz, and the magnetic induction intensity at the center is 50 mT-300 mT; During the cooling process, the average cooling rate from 1100°C to 800°C is less than 15°C / h.

2. The method for synergistic recovery of multiple metals from copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to claim 1, characterized in that, The mass ratio of the reducing component to the sulfurizing component is 1:2-7; And / or, the particle size of the composite conditioning agent is 3mm-8mm.

3. The method for multi-metal synergistic recovery of copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to claim 1, characterized in that, The mass ratio of the liquid copper-molybdenum smelting slag to the composite conditioning agent is 1:0.05-0.

2.

4. The method for multi-metal synergistic recovery of copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to claim 1, characterized in that, The reaction temperature is 1200-1500℃, and the time is 45-180 min; And / or, the flue gas contains lead, zinc, or their oxides or sulfides.

5. The method for multi-metal synergistic recovery of copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to claim 1, characterized in that, The mass content of particles with a particle size of less than or equal to 0.074 mm in the matte phase after grinding is ≥90%.

6. The method for multi-metal synergistic recovery of copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to claim 1, characterized in that, The collector includes at least one of butyl xanthate, isopentyl xanthate, and butylammonium black powder; And / or, the inhibitor includes at least one of sodium sulfide, sodium hydrosulfide, and Knox pharmaceuticals.

7. The method for multi-metal synergistic recovery of copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to claim 6, characterized in that, The mass ratio of the collector to the ground matte phase is 0.0005-0.002:1; And / or, the mass ratio of the inhibitor to the milled matte phase is 0.003-0.015:

1.

8. The method for multi-metal synergistic recovery of copper-molybdenum smelting slag based on composite conditioning and external field enhancement according to any one of claims 1-7, characterized in that, The pH of the coarse selection is 8.5-12.0.

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