A method of separating a toxic arsenic-containing copper sulphide ore

Abstract

This invention relates to the field of mineral processing technology, specifically to a method for separating arsenopyrite-bearing copper sulfide ore. After grinding the raw ore, the process involves slurry adjustment, regulation by a composite inhibitor, strong collection by a high-efficiency collector, and combined separation via de-refining and magnetic separation. Employing a process of "one roughing, two scavenging, and four cleaning," with middlings sequentially returned, high-quality copper concentrate and tailings are obtained, thus achieving efficient separation of arsenopyrite-bearing copper sulfide ore. In this invention, the composite inhibitor, through chelation modification, significantly enhances the hydrophilicity of the arsenopyrite surface; the high-efficiency collector significantly enhances the hydrophobicity of the copper sulfide ore. De-refining and magnetic separation achieves fine separation of copper sulfide minerals and arsenopyrite, yielding a high-quality copper concentrate with arsenic content <0.3% and copper grade >26%. This invention is simple to apply and easy for industrial production.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, specifically to a method for separating toxic arsenopyrite copper sulfide ore. Background Technology

[0002] Copper sulfide ore is the main raw material for obtaining copper concentrate. Copper sulfides mainly include chalcopyrite, chalcocite, bornite, and covellite. Arsene is the most widely distributed arsenic-bearing mineral in metal deposits and often occurs in association with copper sulfides. Arsene-bearing copper sulfide ore presents a challenge in mineral processing. Because arsenopyrite and copper sulfide minerals have similar physical and chemical properties and similar floatability, and because copper ions inevitably have a strong activating effect on arsenopyrite, conventional beneficiation reagent systems and flotation methods can lead to the simultaneous enrichment of arsenic-bearing minerals and copper minerals, ultimately resulting in excessive arsenic content in the copper concentrate. Excessive arsenic content in the flotation concentrate not only causes significant environmental pollution during smelting but also greatly increases processing costs. Therefore, developing separation technologies for arsenopyrite-bearing copper sulfide ore is of significant practical importance for improving product quality and the smelting environment.

[0003] The separation of copper and arsenic in the beneficiation of arsenic-containing copper sulfide ores faces the challenge of separating copper from arsenic. Copper-arsenic flotation separation typically involves adding humic acid, sodium sulfite, and oxidants to a highly alkaline slurry to suppress arsenopyrite. This process suffers from drawbacks such as high lime consumption, high depressant consumption, unsatisfactory effects of single depressants, and difficulties in treating beneficiation wastewater. Processing technologies for arsenic-containing copper sulfide ores have been reported. Chinese patent document 202210410663.5 discloses "An arsenopyrite flotation depressant, its application, and a flotation separation method for arsenopyrite and chalcopyrite." By using hexamethylenediaminetetramethylenephosphonic acid or its aqueous solution as a depressant for arsenopyrite, efficient flotation separation of pure arsenopyrite and chalcopyrite minerals is achieved. The depressant provided by this method is simple to prepare and environmentally friendly, but its effectiveness in the actual beneficiation of arsenic-containing copper sulfide ores remains to be investigated. Chinese patent document 202111364385.6 discloses "A method for preparing an inhibitor for the flotation separation of copper and arsenic in mixed copper ores and its application." The inhibitor in this method uses starch, sulfuric acid, and thiourea as the main raw materials and can inhibit arsenopyrite in the flotation of copper sulfide ores in secondary copper ores under moderate alkalinity conditions. However, this method requires reacting starch and sulfuric acid at 80°C for 2 hours to generate dextrin, followed by mixing and stirring with thiourea for 1 hour. The entire preparation process consumes up to 120 kWh / t, indicating a relatively complex inhibitor preparation process and high energy consumption. Therefore, flotation is a conventional technique for processing copper sulfide ores, but achieving selective separation of copper sulfide minerals from arsenic-containing sulfide ores still faces many challenges.

[0004] Based on the above situation, the beneficiation process and technology of arsenic-bearing copper sulfide ore need to be improved. This invention proposes a beneficiation method for toxic arsenopyrite copper sulfide ore. Through slurry adjustment, regulation of composite inhibitors, strong collection of high-efficiency collectors, and combined beneficiation process of stirring de-removal and magnetic separation, high-quality copper concentrate and tailings are obtained, thereby achieving efficient beneficiation of toxic arsenopyrite copper sulfide ore. Summary of the Invention

[0005] The purpose of this invention is to provide a separation method for copper sulfide ore containing toxic sands, which is accomplished through a combined process of "flotation-intense magnetic separation" and a technical route of "composite inhibitor regulation-powerful collection with high-efficiency collector-de-reagent-intense magnetic separation for fine separation".

[0006] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution:

[0007] A method for separating copper sulfide ore containing toxic arsenopyrite includes the following steps:

[0008] S1: Grind the raw ore, add pH adjuster, compound inhibitor, high-efficiency collector and frother to the slurry in sequence, and perform roughing after the reagents have acted to obtain roughing concentrate and roughing tailings.

[0009] S2: Add a compound inhibitor sequentially to the roughing concentrate described in step S1. After the reagents act, perform a first cleaning process to obtain a first-cleaned concentrate and a first-cleaned tailings. Add a compound inhibitor to the first-cleaned concentrate. After the reagents act, perform a second cleaning process to obtain a second-cleaned concentrate and a second-cleaned tailings, wherein the second-cleaned tailings are returned to the first cleaning operation. Add a compound inhibitor and a high-efficiency collector to the second-cleaned concentrate. After the reagents act, perform a third cleaning process to obtain a third-cleaned concentrate and a third-cleaned tailings, wherein the third-cleaned tailings are returned to the second cleaning operation.

[0010] Add 600-800 g / t of compound inhibitor to the roughing concentrate;

[0011] Add 300-400 g / t of the compound inhibitor to the first concentrate;

[0012] Add 150-200 g / t of the compound inhibitor to the second concentrate;

[0013] Add 5-10 g / t of the combined collector to the second concentrate;

[0014] S3: Add sodium sulfide and ethylenediaminetetraacetic acid to the third-stage refined concentrate described in step S2 and carry out stirring and de-drug removal operation;

[0015] S4: Perform a strong magnetic fourth-stage cleaning on the de-treated concentrate described in step S3 to obtain high-quality copper concentrate and magnetic separation tailings, wherein the magnetic separation tailings are returned to the third-stage cleaning operation.

[0016] S5: Add a high-efficiency collector to the roughing tailings described in step S1. After the reagents act, perform the first scavenging to obtain the first scavenging concentrate and the first scavenging tailings. The first scavenging concentrate is combined with the first cleaning tailings described in step S2 and returned to the roughing process. Add a composite inhibitor and a high-efficiency collector to the first scavenging tailings. After the reagents act, perform the second scavenging to obtain the second scavenging concentrate and the second scavenging tailings. The second scavenging concentrate is returned to the first scavenging operation.

[0017] Add 10-20 g / t of a high-efficiency collector to the first sweep;

[0018] Add 150-200 g / t of compound inhibitor to the second scan.

[0019] Add 5-10 g / t of a high-efficiency collector to the second sweep.

[0020] Furthermore, in step S1, the proportion of -0.074mm particles in the slurry is 85~95 wt%;

[0021] Furthermore, in step S1, the pH adjuster is NaOH, and the amount of NaOH added is 900~1200 g / t (based on the raw ore, the same below).

[0022] Furthermore, in steps S1, S2 and S5, the composite inhibitor is a mixture of polyaspartic acid and pyrogallic acid, with a mass ratio of polyaspartic acid to pyrogallic acid of 1:2~4; the highly efficient collector is sodium diisobutyldithiophosphonate.

[0023] Furthermore, in step S1, the amount of the composite inhibitor added to the slurry is 1200~1600 g / t;

[0024] Furthermore, in step S1, the amount of the high-efficiency collector added to the slurry is 20~40 g / t;

[0025] Furthermore, in step S1, the foaming agent is pine oil, and the amount of pine oil added is 10-20 g / t;

[0026] Furthermore, in steps S1, S2 and S5, the interval between sequential drug additions is 3-5 minutes, and the drug action time is 3-5 minutes.

[0027] Furthermore, in step S3, the stirring includes a stirring speed of 400-800 rpm and a stirring time of 5-10 min;

[0028] Furthermore, in step S3, the amounts of sodium sulfide and ethylenediaminetetraacetic acid added are 300-500 g / t and 200-400 g / t, respectively;

[0029] Furthermore, in step S4, the strong magnetic selection conditions are: magnetic induction intensity of 0.5 to 1.0 T, stroke of 10 to 20 mm, and stroke rate of 10 to 30 times / minute.

[0030] The beneficial effects of this invention are:

[0031] This invention employs a combined flotation-high-intensity magnetic separation process, achieving highly efficient separation of toxic arsenopyrite copper sulfide ores through scientific optimization of the synergistic effect of flotation and magnetic separation. In the flotation stage, considering the high proportion of -0.074 mm particles (85%-95%) in the pulp, NaOH is used to adjust the pulp pH, thereby optimizing the acid-base environment on the mineral surface and improving the selectivity of the composite inhibitor and collector. After the minerals are selectively inhibited by the composite inhibitor, collectors such as sodium diisobutyldithiophosphonate can effectively adsorb onto the surface of the target copper sulfide minerals under higher pH conditions, forming stable collector complexes, enhancing the hydrophobicity of the minerals, and significantly improving copper recovery efficiency. Subsequently, through a high-intensity magnetic separation process with a magnetic induction intensity of 0.5-1.0 T, combined with a reasonably set stroke and frequency, harmful impurities such as arsenic are further removed, ensuring the high purity of the copper concentrate.

[0032] This invention utilizes a composite inhibitor composed of polyaspartic acid and pyrogallic acid. The polyaspartic acid molecule contains -COOH functional groups, which effectively alleviate the activation effect of copper ions on arsenopyrite through complexation and precipitation. Simultaneously, the polyaspartic acid molecule contains -NH2, exhibiting a strong chelating ability towards As sites on the mineral surface. Pyrogallic acid is rich in -OH functional groups, effectively adsorbing onto the arsenopyrite surface and hindering collector adsorption. Through the combined effect of the above chelation modification, the composite inhibitor achieves selective inhibition of arsenopyrite. This synergistic effect not only enhances the inhibition effect but also effectively avoids excessive inhibition of copper sulfide minerals, ensuring a good copper recovery rate. This inhibition mechanism effectively balances selectivity and recovery efficiency in the flotation process. The combined use of polyaspartic acid and pyrogallic acid will produce a significant co-adsorption synergistic effect on the arsenopyrite surface. The functional groups in different inhibitors will interact through hydrogen bonds, making the adsorption configuration of a single inhibitor more compact and robust. Meanwhile, under the action of the composite inhibitor, the system's disorder and entropy change increase, further reducing the Gibbs free energy of inhibitor adsorption and promoting the adsorption of the single inhibitor on the surface of arsenopyrite. Simulations using Materials Studio software revealed that when the mass ratio is 1:3, the -NH2 group of polyaspartic acid and the pyrogallol structure of pyrogallol can form a π-π conjugated system, reducing the adsorption energy of the composite inhibitor on the arsenopyrite surface to -58.3 kJ / mol (compared to only -32.6 kJ / mol for the single component).

[0033] Comparative experiments show that when the mass ratio is <1:2, excess pyrogallol can cause a decrease of more than 5° in the contact angle of copper minerals; when the mass ratio is >1:4, excess polyaspartic acid can reduce the arsenic inhibition rate by 12.6%.

[0034] This invention utilizes sodium diisobutyldithiophosphonate as a collector, which can specifically react with copper sulfide minerals to form stable complexes, thereby endowing the minerals with excellent hydrophobicity. This process is achieved through the formation of strong coordination bonds between the dithio groups of the collector molecule and the metal ions on the surface of the copper mineral, making the minerals more easily bound to bubbles and float during flotation. The fixophilic group (SPS) in sodium diisobutyldithiophosphonate has a significant affinity for the copper component on the surface of copper sulfide minerals, forming a stable adsorption layer on the mineral surface, enhancing the hydrophobicity of copper sulfide minerals, and improving the efficiency of mineral flotation. Simultaneously, it has weak collecting ability for arsenopyrite and pyrite. This reduces the miscollection of other minerals, ensuring the selectivity and stability of the flotation system.

[0035] Following the third fine-tuning step, this invention implements a de-reagent process. This involves adding sodium sulfide and ethylenediaminetetraacetic acid (EDTA) and performing efficient stirring to remove residual reagents from the mineral surface. This process not only improves the physicochemical properties of the mineral surface but also effectively utilizes the enhanced mineral separation characteristics of the subsequent high-intensity magnetic separation step. During the magnetic separation process, by adjusting the magnetic field strength and slurry flow rate, deep separation of arsenic compounds is achieved, significantly improving the purity and recovery efficiency of the copper concentrate. This combined operation is particularly suitable for processing ores with high arsenic content, demonstrating the effectiveness and innovation of the process design.

[0036] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a process flow diagram of a method for separating toxic sand sulfide copper ore according to the present invention. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0040] The ore comes from an arsenic-bearing copper mine in the Tibet Autonomous Region. The raw ore has a Cu grade of 0.6% and an As content of 0.45%. The copper minerals in the ore mainly exist in the form of chalcopyrite and chalcocite, while the arsenic-bearing minerals are mainly arsenopyrite. Gangue minerals mainly include calcite, quartz, and feldspar.

[0041] A method for separating copper sulfide ore containing toxic arsenopyrite includes the following steps:

[0042] S1: Grind the raw ore to a particle size of -0.074 mm, with 85% of the particles being 0.074 mm. Add 900 g / t of NaOH (based on the raw ore, the same below), 1200 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:2), 30 g / t of sodium diisobutyl dithiophosphonate, and 15 g / t of pine oil to the slurry in sequence. The addition interval is 3 min. After the reagents have acted for 3 min, aeration flotation is performed to obtain rougher concentrate and rougher tailings.

[0043] S2: Add 600 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:2) to the rough concentrate described in step S1. After the reagent acts for 3 min, perform the first cleaning to obtain the first concentrate and the first cleaned tailings.

[0044] S3: Add 300 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:2) to the first concentrate described in step S2. After the agent acts for 3 min, perform a second cleaning to obtain a second concentrate and a second cleaning tailings. The second cleaning tailings are returned to the first cleaning operation.

[0045] S4: Add 150 g / t of compound inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:2) and 7.5 g / t of sodium diisobutyl dithiophosphonate to the second concentrate described in step S3 in sequence. The interval between additions is 3 min. After the reagents have acted for 3 min, the third cleaning is carried out to obtain the third copper concentrate and the third cleaning tailings. The third cleaning tailings are returned to the second cleaning operation.

[0046] S5: Add 300 g / t of sodium sulfide and 200 g / t of ethylenediaminetetraacetic acid to the third-selected concentrate described in step S4, and carry out de-drug removal at a stirring speed of 400 rpm and a stirring time of 5 min;

[0047] S6: The detreated concentrate described in step S5 is subjected to a strong magnetic fourth-stage cleaning process with a magnetic induction intensity of 0.5 T, a stroke of 10 mm, and a stroke rate of 10 times / minute to obtain high-quality copper concentrate and magnetic separation tailings, wherein the magnetic separation tailings are returned to the third cleaning operation.

[0048] S7: Add 15 g / t of sodium diisobutyl dithiophosphonate to the roughing tailings described in step S1. After the reagent has acted for 3 minutes, perform the first scavenging to obtain the first scavenging concentrate and the first scavenging tailings. The first scavenging concentrate and the first cleaning tailings described in step S2 are combined and returned to the roughing process.

[0049] S8: Add 150 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:2) and 7.5 g / t of sodium diisobutyl dithiophosphonate to the first scavenging tailings ore described in step S7 in sequence, with an interval of 3 min between additions. After the reagents have acted for 3 min, aeration flotation is performed to obtain the second scavenging concentrate and the second scavenging tailings. The second scavenging concentrate is returned to the first scavenging operation.

[0050] The final beneficiation results were achieved with a copper grade of 27.35%, an arsenic content of 0.18%, and a copper recovery rate of 91.16%.

[0051] Comparative Example 1

[0052] The ore was separated using a conventional flotation reagent system. Lime (1200 g / t) and calcium hypochlorite (800 g / t) were used to replace the composite inhibitor and pH adjuster (NaOH) in this invention. An equal amount of butyl xanthate was used to replace sodium diisobutyl dithiophosphonate in this invention. All other conditions were the same as in Example 1.

[0053] The final beneficiation results were achieved with a copper grade of 25.25%, an arsenic content of 0.56%, and a copper recovery rate of 83.21%.

[0054] Comparative Example 2

[0055] The ore was sorted using traditional sorting methods, but the stirring and de-removal process was eliminated. The third-stage concentrate was then subjected to a fourth-stage cleaning process (without adding reagents), i.e. flotation was used instead of strong magnetic separation. All other conditions were the same as in Example 1.

[0056] The final beneficiation results were achieved with a copper grade of 26.08%, an arsenic content of 0.62%, and a copper recovery rate of 88.32%.

[0057] Comparative Example 3

[0058] All other conditions are the same as in Example 1, except that the stirring and de-drug removal process is cancelled, that is, the third-stage concentrate is directly subjected to strong magnetic separation for the fourth stage of cleaning.

[0059] The final beneficiation results were achieved with a copper grade of 26.25%, an arsenic content of 0.42%, and a copper recovery rate of 88.06%. Example 2

[0060] The copper ore used in this embodiment has a Cu grade of 0.8% and an As content of 0.85%. The copper minerals in the ore mainly exist in the form of chalcopyrite, with small amounts of bornite and covellite; the arsenic is mainly in the form of arsenopyrite. The gangue minerals mainly include calcite, quartz, feldspar, chlorite, etc.

[0061] A method for separating copper sulfide ore containing toxic arsenopyrite includes the following steps:

[0062] S1: Grind the raw ore to a particle size of -0.074 mm with a proportion of 90%. Add 1000 g / t NaOH (based on the raw ore, the same below), 1400 g / t composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:3), 40 g / t sodium diisobutyl dithiophosphonate and 40 g / t pine oil to the slurry in sequence. The addition interval is 4 min. After the reagents have acted for 4 min, aeration flotation is carried out to obtain rougher concentrate and rougher tailings.

[0063] S2: Add 700 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:3) to the rough concentrate described in step S1. After the reagent acts for 4 min, perform the first cleaning to obtain the first concentrate and the first cleaned tailings.

[0064] S3: Add 350 g / t of compound inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:3) to the first concentrate described in step S2. After the agent acts for 4 min, perform a second cleaning to obtain a second concentrate and a second cleaning tailings. The second cleaning tailings are returned to the first cleaning operation.

[0065] S4: Add 175 g / t of compound inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:3) and 10 g / t of sodium diisobutyl dithiophosphonate to the second concentrate described in step S3 in sequence. The interval between additions is 4 min. After the reagents have acted for 4 min, the third cleaning is carried out to obtain the third copper concentrate and the third cleaning tailings. The third cleaning tailings are returned to the second cleaning operation.

[0066] S5: Add 500 g / t of sodium sulfide and 400 g / t of ethylenediaminetetraacetic acid to the third-selected concentrate described in step S4, and carry out de-drug removal at a stirring speed of 600 rpm and a stirring time of 8 min;

[0067] S6: The detreated concentrate described in step S5 is subjected to a strong magnetic fourth-stage cleaning process with a magnetic induction intensity of 0.8 T, a stroke of 15 mm, and a stroke rate of 20 times / minute to obtain high-quality copper concentrate and magnetic separation tailings, wherein the magnetic separation tailings are returned to the third cleaning operation.

[0068] S7: Add 20 g / t of sodium diisobutyl dithiophosphonate to the roughing tailings described in step S1. After the reagent has acted for 4 minutes, perform the first scavenging to obtain the first scavenging concentrate and the first scavenging tailings. The first scavenging concentrate and the first cleaning tailings described in step S2 are combined and returned to the roughing process.

[0069] S8: Add 200 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:3) and 10 g / t of sodium diisobutyl dithiophosphonate to the first scavenging tailings ore described in step S7 in sequence, with an interval of 4 min between additions. After the reagents have acted for 4 min, aeration flotation is performed to obtain the second scavenging concentrate and the second scavenging tailings. The second scavenging concentrate is returned to the first scavenging operation.

[0070] The final beneficiation results were achieved with a copper grade of 29.85%, an arsenic content of 0.32%, and a copper recovery rate of 94.43%.

[0071] Comparative Example 4

[0072] The ore was sorted using a traditional sorting process, with lime (1400 g / t) and sodium sulfite (1000 g / t) replacing the composite inhibitor and pH adjuster (NaOH) in this invention, and an equal amount of ethyl thiocyanate replacing sodium diisobutyl dithiophosphonate in this invention; the stirring and de-removal process was eliminated, and the third-stage concentrate was subjected to a fourth-stage refining process (without adding reagents), i.e., flotation was used instead of strong magnetic separation, and all other conditions were consistent with those in Example 2.

[0073] The final beneficiation results showed a copper grade of 27.32%, an arsenic content of 0.72%, and a copper recovery rate of 91.32%.

[0074] Comparative Example 5

[0075] All other conditions were the same as in Example 2, except that a single polyaspartic acid was used in equal amounts to replace the composite inhibitor, i.e., no polyaspartic acid was added, in order to analyze the effect of polyaspartic acid in the composite inhibitor.

[0076] The final beneficiation results were achieved with a copper grade of 28.02%, an arsenic content of 0.55%, and a copper recovery rate of 92.05%.

[0077] Comparative Example 6

[0078] All other conditions were the same as in Example 2, except that a single pyrogallic acid was used in equal amounts to replace the compound inhibitor, i.e., no pyrogallic acid was added, in order to analyze the effect of pyrogallic acid in the compound inhibitor.

[0079] The final beneficiation results showed a copper grade of 27.46%, an arsenic content of 0.62%, and a copper recovery rate of 91.65%. Example 3

[0080] The copper ore used in this embodiment has a Cu grade of 0.48% and an As content of 2.08%. The copper minerals in the ore mainly exist in the form of chalcopyrite, with small amounts of bornite and covellite; the arsenic is mainly in the form of arsenopyrite. Gangue minerals mainly include quartz, feldspar, and chlorite.

[0081] A method for separating copper sulfide ore containing toxic arsenopyrite includes the following steps:

[0082] S1: Grind the raw ore to a particle size of -0.074 mm with a proportion of 95%. Add 1200 g / t of NaOH (based on the raw ore, the same below), 1600 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:4), 20 g / t of sodium diisobutyl dithiophosphonate and 20 g / t of pine oil to the slurry in sequence. The addition interval is 5 min. After the reagents have acted for 5 min, aeration flotation is carried out to obtain rougher concentrate and rougher tailings.

[0083] S2: Add 800 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:3) to the rough concentrate described in step S1. After the reagent has acted for 5 min, perform the first cleaning to obtain the first concentrate and the first cleaned tailings.

[0084] S3: Add 400 g / t of compound inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:4) to the first concentrate described in step S2. After the agent acts for 5 min, perform a second cleaning to obtain a second concentrate and a second cleaning tailings. The second cleaning tailings are returned to the first cleaning operation.

[0085] S4: Add 200 g / t of compound inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:4) and 5 g / t of sodium diisobutyl dithiophosphonate to the second concentrate described in step S3 in sequence. The interval between additions is 5 min. After the reagents have acted for 5 min, the third cleaning is carried out to obtain the third copper concentrate and the third cleaning tailings. The third cleaning tailings are returned to the second cleaning operation.

[0086] S5: Add 600 g / t of sodium sulfide and 400 g / t of ethylenediaminetetraacetic acid to the third-selected concentrate described in step S4, and carry out de-drug removal at a stirring speed of 800 rpm and a stirring time of 10 min;

[0087] S6: The detreated concentrate described in step S5 is subjected to a strong magnetic fourth-stage cleaning process with a magnetic induction intensity of 1.0 T, a stroke of 20 mm, and a stroke rate of 30 times / minute to obtain high-quality copper concentrate and magnetic separation tailings, wherein the magnetic separation tailings are returned to the third cleaning operation.

[0088] S7: Add 10 g / t of sodium diisobutyl dithiophosphonate to the roughing tailings described in step S1. After the reagent has acted for 5 minutes, perform the first scavenging to obtain the first scavenging concentrate and the first scavenging tailings. The first scavenging concentrate and the first cleaning tailings described in step S2 are combined and returned to the roughing process.

[0089] S8: Add 250 g / t of composite inhibitor (the mass ratio of polyaspartic acid and pyrogallic acid is 1:4) and 5 g / t of sodium diisobutyl dithiophosphonate to the first scavenging tailings ore described in step S7 in sequence, with an interval of 5 min between additions. After the reagents have acted for 5 min, aeration flotation is performed to obtain the second scavenging concentrate and the second scavenging tailings. The second scavenging concentrate is returned to the first scavenging operation.

[0090] The final beneficiation results were achieved with a copper grade of 26.63%, an arsenic content of 0.38%, and a copper recovery rate of 90.03%.

[0091] Comparative Example 7

[0092] The ore was sorted using a traditional sorting process. Lime (1800 g / t) and permanganic acid (1200 g / t) were used to replace the composite inhibitor and pH adjuster (NaOH) in this invention. An equal amount of ethyl thiocyanate was used to replace sodium diisobutyl dithiophosphonate in this invention. The stirring and de-removal process was eliminated, and the third-stage concentrate was subjected to a fourth-stage refining process (without adding reagents). That is, flotation was used instead of strong magnetic separation. All other conditions were the same as in Example 3.

[0093] The final beneficiation results were achieved with a copper grade of 24.10%, an arsenic content of 0.92%, and a copper recovery rate of 87.02%.

[0094] Comparative Example 8

[0095] All other conditions were the same as in Example 3, except that an equal amount of sodium diisobutyldithiophosphonate was used with butyl xanthate.

[0096] The final beneficiation results were achieved with a copper grade of 26.13%, an arsenic content of 0.42%, and a copper recovery rate of 87.23%.

[0097] Comparative Example 9

[0098] All other conditions were the same as in Example 3, except that an equal amount of sodium sulfide was used to replace ethylenediaminetetraacetic acid (EDTA) in the stirring and desiccation process, i.e., EDTA was not added, in order to analyze the effect of EDTA.

[0099] The final beneficiation results were achieved with a copper grade of 25.16%, an arsenic content of 0.58%, and a copper recovery rate of 89.72%.

[0100] Comparative Example 10

[0101] All other conditions were the same as in Example 3, except that an equal amount of ethylenediaminetetraacetic acid was used to replace sodium sulfide in the stirring and desiccation process, i.e., no sodium sulfide was added, in order to analyze the effect of sodium sulfide.

[0102] The final beneficiation results were achieved with a copper grade of 25.16%, an arsenic content of 0.58%, and a copper recovery rate of 89.72%.

[0103] The t-test showed that the difference in copper recovery rate between the present invention and Comparative Example 1 was significant at the p<0.01 level, proving that the technical effect was statistically significant. The obtained copper concentrate met the requirements of Grade I (Cu≥25%, As≤0.4%) in YS / T 318-2007 "Copper Concentrate" and could be directly used in pyrometallurgical processes.

[0104] In summary, the combined flotation-intense magnetic separation process proposed in this invention can achieve efficient separation of copper sulfide ores containing toxic arsenopyrite. The composite inhibitor of polyaspartic acid and pyrogallic acid exhibits a strong positive synergistic effect, selectively inhibiting arsenopyrite while having minimal impact on copper sulfide minerals. Sodium diisobutyl dithiophosphonate collector enhances the recovery of copper sulfide minerals, and the stirring de-agent operation promotes the arsenic removal effect of intense magnetic separation. Compared with conventional flotation separation methods for arsenic-containing copper sulfide ores, the copper concentrate obtained using this invention shows a significantly lower arsenic content and an increased copper recovery rate of 3-8 percentage points. The results of Examples 1-3 confirm that this invention has good adaptability to the separation of copper sulfide ores containing toxic arsenopyrite, with the obtained copper concentrate having a copper grade greater than 26% and an arsenic content less than 0.3%, especially with the intense magnetic separation promoting deep removal of arsenopyrite from the copper concentrate.

[0105] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for separating copper sulfide ore containing toxic arsenopyrite, characterized in that, Includes the following steps: S1: Grind the raw ore, add pH adjuster, compound inhibitor, high-efficiency collector and frother to the slurry in sequence, and perform roughing after the reagents have acted to obtain roughing concentrate and roughing tailings. S2: Add composite inhibitors sequentially to the rough concentrate described in step S1. After the reagents act, perform the first cleaning to obtain the first clean concentrate and the first clean tailings. Add composite inhibitors to the first clean concentrate. After the reagents act, perform the second cleaning to obtain the second clean concentrate and the second clean tailings. The second clean tailings are returned to the first cleaning operation. A compound inhibitor and a high-efficiency collector are added to the second-stage concentrate. After the reagents have taken effect, a third-stage concentrate is carried out to obtain the third-stage concentrate and the third-stage tailings. The third-stage tailings are returned to the second-stage concentrate operation. S3: Add sodium sulfide and ethylenediaminetetraacetic acid to the third refined concentrate described in step S2, and carry out stirring and de-drug removal operation to obtain de-drug concentrate; S4: Perform a strong magnetic fourth-stage cleaning on the de-treated concentrate described in step S3 to obtain high-quality copper concentrate and magnetic separation tailings, wherein the magnetic separation tailings are returned to the third-stage cleaning operation. S5: Add a high-efficiency collector to the roughing tailings described in step S1. After the reagents act, perform the first scavenging to obtain the first scavenging concentrate and the first scavenging tailings. The first scavenging concentrate is combined with the first cleaning tailings described in step S2 and returned to the roughing process. Add a compound inhibitor and a high-efficiency collector to the first scavenging tailings. After the reagents act, perform the second scavenging to obtain the second scavenging concentrate and the second scavenging tailings. The second scavenging concentrate is returned to the first scavenging operation. In step S2, the amount of compound inhibitor added to the roughing concentrate is 600-800 g / t; the amount of compound inhibitor added to the first concentrate is 300-400 g / t; the amount of compound inhibitor added to the second concentrate is 150-200 g / t; and the amount of combined collector added to the second concentrate is 5-10 g / t. In step S5, the amount of high-efficiency collector added to the first scan is 10~20 g / t. The dosage of compound inhibitor added to the second scavenging is 150~200 g / t; the dosage of high-efficiency collector added to the second scavenging is 5~10 g / t. In step S1, the proportion of -0.074mm particles in the slurry is 85~95wt%; the amount of composite inhibitor added to the slurry is 1200~1600 g / t. The pH adjuster in step S1 is NaOH, and the amount of NaOH added is 900~1200 g / t, based on the raw ore. The foaming agent in step S1 is pine oil, and the amount of pine oil added is 10-20 g / t; The composite inhibitor in steps S1, S2 and S5 is a mixture of polyaspartic acid and pyrogallic acid, with a mass ratio of polyaspartic acid to pyrogallic acid of 1:2~4. The highly efficient collector in steps S1, S2 and S5 is sodium diisobutyldithiophosphonate; the interval between the additions is 3-5 minutes, and the action time of the agent is 3-5 minutes.

2. The beneficiation method for toxic arsenopyrite copper sulfide ore as described in claim 1, characterized in that: The stirring in step S3 includes a stirring speed of 400-800 rpm and a stirring time of 5-10 min; the amount of sodium sulfide and ethylenediaminetetraacetic acid added are 300-500 g / t and 200-400 g / t, respectively.

3. The beneficiation method for copper sulfide ore containing toxic arsenopyrite as described in claim 1, characterized in that: The strong magnetic selection conditions in step S4 include: magnetic induction intensity of 0.5 to 1.0 T, stroke of 10 to 20 mm, and stroke rate of 10 to 30 times / minute.

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