A beneficiation method for high-sulfur, low-copper type copper sulfide ore containing secondary copper

Abstract

The present invention relates to the technical field of flotation of secondary copper ores, and in particular to a beneficiation method for a high-sulfur, low-copper copper sulfide ore containing secondary copper, comprising grinding, mixed flotation, and copper-sulfur separation flotation. An organic polyphosphonic acid is added as a pulp conditioner during grinding, mixed flotation includes three flotations, and the resulting coarse concentrate is collected. In the copper-sulfur separation flotation, the coarse concentrate obtained by the three flotations is first regrinded with a pyrite combination depressant. The resulting pulp after regrinding is then subjected to copper-sulfur separation flotation, and the concentrate obtained by the copper-sulfur separation flotation is a copper concentrate. The present invention provides a beneficiation method for a high-sulfur, low-copper copper sulfide ore containing secondary copper, which can effectively inhibit pyrite in the presence of secondary copper, thereby achieving efficient separation of the high-sulfur, low-copper copper sulfide ore containing secondary copper.

Description

Technical Field

[0001] The present invention relates to the technical field of flotation of secondary copper ore, in particular to a beneficiation method for high-sulfur and low-copper sulfide copper ore containing secondary copper. Technical Background

[0002] Copper sulfide minerals are divided into primary copper ores and secondary copper ores. Compared to primary copper sulfide (chalcopyrite CuFeS2), secondary copper sulfide minerals occur in nature in a wider variety, such as bornite (Cu5FeS4), chalcocite (Cu2S), and covellite (CuS). These secondary copper ores are formed through the oxidation and decomposition of primary sulfides, followed by reduction, impregnation, and migration. Secondary copper minerals are brittle and easily over-grinded. During ore dressing and grinding, copper ions are easily dissolved, which in turn deteriorates the flotation environment and activates non-target minerals such as pyrite, interfering with the normal flotation process. Copper sulfide ores often contain pyrite. When the pyrite content in the ore is high and the copper-sulfur ratio is low, the separation of chalcopyrite becomes more difficult. The presence of secondary copper sulfide ores, which leads to the activation of pyrite, undoubtedly increases the difficulty of separating this type of ore.

[0003] For copper sulfide ores with low copper-sulfur ratios, inhibiting pyrite during the recovery process is an inevitable problem. The most common method for inhibiting pyrite is the lime method, which has the advantages of good inhibition effect and relatively low cost, but its strong alkalinity can easily cause problems such as high pH value of mineral processing wastewater, easy blockage of pipelines, and low recovery rate of precious metals. In addition, it also includes redox agent methods mainly represented by sodium sulfite, potassium permanganate, hypochlorite, etc., and various organic inhibitor methods represented by sodium humate, dextrin, tannin, etc. However, when the ore contains secondary copper, the copper ions in the slurry will activate pyrite, making it more difficult to inhibit pyrite. A higher alkalinity is required to achieve a better inhibition effect. The above-mentioned agents have weak inhibitory effects on pyrite.

[0004] In the existing technology, in order to address the adverse effects of secondary copper ore on the flotation of high-sulfur, low-copper sulfide copper ores, reducing the concentration of free copper ions during the grinding stage is an effective means. There are currently two main solutions:

[0005] First, measures are taken during the grinding stage to reduce the free copper ion content in the solution, weakening or eliminating the copper ion's activation of non-target minerals, thereby addressing the problem of secondary copper minerals affecting sulfide ore flotation at the source. Sulfide precipitation is a widely used method. For example, patent CN101722096 A proposes adding sodium carbonate and sodium sulfide during grinding to precipitate copper ions. Patent CN 110026293 A proposes adding sodium sulfide during grinding to eliminate the effects of copper ions. However, the addition of sodium sulfide can have a certain negative impact on the flotation of sulfide ores.

[0006] The second is to use targeted inhibitors to inhibit pyrite that has been activated by copper ions. For example, the paper "Zhang Yahui, Ji Tingting, Li Yan, Zhou Chao, Shi Wei.Cu 2+ Flotation separation of activated pyrite and chalcopyrite [J]. Metal Mines, 2010 (12): 46-49. It is proposed to use citric acid, sodium bisulfite and lime as a combination of reagents to inhibit the formation of Cu 2+ Activated pyrite: Patent CN106540816A proposes using calcium oxide, sodium hypochlorite, and sodium humate to inhibit pyrite activated by copper ions. These inhibitors either have insufficient inhibitory capabilities or have negative environmental impacts due to the presence of hypochlorite.

[0007] Therefore, it is necessary to develop sulfur inhibitors specifically for this type of ore to achieve efficient separation of high-sulfur, low-copper copper sulfide ores containing secondary copper. Summary of the Invention

[0008] In order to solve the above problems, the present invention provides a beneficiation method for high-sulfur, low-copper type copper sulfide ore containing secondary copper.

[0009] The present invention adopts the following technical solutions:

[0010] A beneficiation method for a high-sulfur, low-copper copper sulfide ore containing secondary copper comprises the following steps:

[0011] S1. Grinding: Grinding the copper sulfide ore into pulp, adding an organic polyphosphonic acid as a pulp conditioner during the grinding process;

[0012] S2 mixed flotation: The pulp prepared in S1 is mixed with a flotation agent and subjected to three flotation steps, and the coarse concentrate obtained by the three flotation steps is collected;

[0013] S3. Copper-sulfur separation flotation: The coarse concentrate obtained from the three flotation steps is first regrinded, during which a pyrite combination depressant is added. The resulting pulp is then subjected to copper-sulfur separation flotation, and the concentrate obtained from this separation flotation is the copper concentrate. The pyrite combination depressant is a mixture of calcium oxide, hydrogen peroxide, high molecular weight organic matter, and a synergist, and the amount of pyrite combination depressant added is 500-1500 g / t. 矿石 .

[0014] Preferably, the high molecular weight organic matter is any one or more of sodium humate, dextrin, and tannin; and the synergist is magnesium silicate.

[0015] Preferably, the calcium oxide, hydrogen peroxide, high molecular weight organic matter and synergist are mixed in a mass ratio of (20-50):(10-25):(1-5):(5-10).

[0016] Preferably, in step S1, the ore is ground until the ore particles with a particle size of less than 0.074 mm account for more than 60% of the total ore mass content.

[0017] Preferably, in step S1, the organic polyphosphonic acid is any one or more of hydroxyethylidene-1,1-diphosphonic acid HEDP, aminotrimethylenephosphonic acid ATMP, and diethylenetriaminepentamethylenephosphonic acid HTPMP, and the addition amount is 50-150g / t 矿石 .

[0018] Preferably, in step S2, the flotation reagent includes a collector and a foaming agent, the collector is a combination of xanthate and ethionamide in a mass ratio of 2:1, and the foaming agent is No. 2 oil; the amount of the flotation reagent is 20-100 / t 矿石 .

[0019] Preferably, in step S3, the regrinding operation is performed until the ore particles with a particle size of less than 0.045 mm account for more than 70% of the total ore mass content.

[0020] Preferably, in step S3, before the copper-sulfur separation flotation is carried out on the regrinded pulp, a collector is added, wherein the collector is ethiocarbamate, and the addition amount is 20-100 / t 矿石 .

[0021] The beneficial effects of the present invention are:

[0022] Reducing the concentration of free copper ions during the grinding stage is an effective means of addressing the impact of secondary copper minerals on sulfide ore flotation. Chelating ligands contain two or more coordinating atoms, which simultaneously form a chelate ring with a central atom (or ion). Due to the cyclization of the chelating agent, the chelate complex is more stable than non-chelating coordination compounds with similar composition and structure. Through extensive practice, the inventors have discovered that using polybasic organophosphoric acid as a chelating agent has the advantages of strong chelating ability and stable chelates, and can be used in the flotation of high-sulfur, low-copper copper sulfide ores targeting secondary copper ores.

[0023] In the present invention, one molecule of organic polyphosphonic acid can chelate with two or more metal ions to form a three-dimensional bicyclic or polycyclic chelate, and the chelate is stable. Taking HEDP as an example, HEDP is a pentabasic acid. After ionization in water, it forms 5 coordinated oxygen atoms, which can react with Cu 2+ Form a stable chelate to reduce the activation of copper ions on pyrite. In addition, organic polyphosphonic acid can also chelate Ca 2+ Mg 2+ 、Fe 2+ 、Fe 3+The phosphonic acid group is directly connected to the carbon atom, and the low polarity of the PC bond makes the structure of polyphosphate very stable, which has little pollution to water bodies.

[0024] In the copper-sulfur separation flotation stage, the pyrite combination inhibitor composed of "calcium oxide + oxidant + macromolecular organic matter" provided by the present invention has a relatively good effect on pyrite that has been activated by copper ions. Hydrogen peroxide is a relatively environmentally friendly oxidant. Generally, its effect will be weakened in an alkaline environment and in the presence of metal ions, resulting in a poor inhibitory effect. The composite formula of the present invention has a relatively good inhibitory effect on hydrogen peroxide ions HO2 - It has excellent physical and chemical adsorption properties and also has an adsorption effect on metal ions (such as Fe and Mn ions), which can reduce their catalytic effect and prevent their rapid and violent decomposition, thereby ensuring that hydrogen peroxide can fully exert its oxidative effect and achieve the effect of inhibiting pyrite. The present invention increases the effectiveness of the combined inhibitor through a composite formula, improving the effectiveness of the combined inhibitor.

[0025] The present invention provides a beneficiation method for high-sulfur, low-copper copper sulfide ore containing secondary copper, which can effectively inhibit pyrite in the presence of secondary copper, thereby achieving efficient separation of high-sulfur, low-copper copper sulfide ore containing secondary copper. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the process of the present invention. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is described in more detail below with reference to the embodiments.

[0028] Example 1

[0029] A copper ore contains 0.53% copper and 6.34% sulfur, with secondary copper accounting for 15% of the total copper. A beneficiation method for a high-sulfur, low-copper sulfide copper ore containing secondary copper, provided by the present invention, is used to recover copper concentrate. The process is as follows:

[0030] S1. Grinding: Grind the copper sulfide ore into pulp, and the grinding process is carried out at a rate of 100g / t 矿石 Hydroxyethylidene-1,1-diphosphonic acid (HEDP) was added to obtain a slurry having a fineness of -0.074 mm and accounting for 60%.

[0031] S2. Mixed flotation: The pulp prepared in S1 was subjected to three-stage roughing, using a mixture of butyl xanthate and ethiocarbamate in a mass ratio of 2:1 as the first collector. The addition amount of the first collector in the three stages of roughing was 40g / t 矿石 , 20g / t 矿石 、10g / t矿石 , the dosage of the first foaming agent is 12g / t 矿石 , 8g / t 矿石 , 4g / t 矿石 , collect the coarse concentrate obtained by three flotation steps.

[0032] S3. Copper-sulfur separation flotation: The coarse concentrate obtained from the three flotation steps is firstly regrinded to obtain a copper-sulfur separation pulp with a fineness of -0.045mm accounting for 70%. During the regrinding process, 400g / t of calcium oxide is added. 矿石 , hydrogen peroxide 200g / t 矿石 , dextrin 10g / t 矿石 , magnesium silicate 50g / t 矿石 . Add 10g / t 矿石 The second collector ethylthiocarbamate is used for slurry preparation, and the slurry after slurry preparation is subjected to copper-sulfur separation flotation, and the concentrate obtained by the copper-sulfur separation flotation is the copper concentrate.

[0033] Analysis of the flotation results showed that the copper grade in the copper concentrate was 24.12% and the copper recovery rate was 90.11%.

[0034] The above beneficiation process was repeated in Comparative Example 1 without adding HEDP and in Comparative Example 2 without adding magnesium silicate. In Comparative Example 1, a copper concentrate with a copper grade of 23.78% and a copper recovery rate of 89.93% was obtained. In Comparative Example 2, a copper concentrate with a copper grade of 23.45% and a copper recovery rate of 90.02% was obtained, both of which were lower than the beneficiation method provided by the present invention.

[0035] Example 2

[0036] A copper ore contains 0.69% copper and 8.76% sulfur, with secondary copper accounting for 23% of the total copper. A beneficiation method for a high-sulfur, low-copper sulfide copper ore containing secondary copper, provided by the present invention, is used to recover copper concentrate. The process is as follows:

[0037] S1. Grinding: Grind the copper sulfide ore into pulp, and grind it at 150g / t 矿石 Hydroxyethylidene-1,1-diphosphonic acid (HEDP) was added to obtain a slurry having a fineness of -0.074 mm and accounting for 60%.

[0038] S2. Mixed flotation: The pulp prepared in S1 was subjected to three-stage roughing, using a mixture of butyl xanthate and ethiocarbamate in a mass ratio of 2:1 as the first collector. The addition amount of the first collector in the three-stage roughing was 40g / t 矿石 , 20g / t 矿石 、10g / t 矿石 , the dosage of the first foaming agent is 12g / t 矿石 , 8g / t 矿石 , 4g / t 矿石, collect the coarse concentrate obtained by three flotation steps.

[0039] S3. Copper-sulfur separation flotation: The coarse concentrate obtained from the three flotation steps is firstly regrinded to obtain a copper-sulfur separation pulp with a fineness of -0.045mm accounting for 70%. 500g / t calcium oxide is added during the regrinding process. 矿石 , hydrogen peroxide 250g / t 矿石 , dextrin 15g / t 矿石 , magnesium silicate 50g / t 矿石 . Add 10g / t 矿石 The second collector ethylthiocarbamate is used for slurry preparation, and the slurry after slurry preparation is subjected to copper-sulfur separation flotation, and the concentrate obtained by the copper-sulfur separation flotation is the copper concentrate.

[0040] Analysis of the flotation results showed that the copper grade in the copper concentrate was 25.78% and the copper recovery rate was 91.56%.

[0041] The above beneficiation process was repeated in Comparative Example 1 without adding HEDP and in Comparative Example 2 without adding magnesium silicate. In Comparative Example 1, a copper concentrate with a copper grade of 24.56% and a copper recovery rate of 91.43% was obtained. In Comparative Example 2, a copper concentrate with a copper grade of 24.34% and a copper recovery rate of 91.32% was obtained, both of which were lower than the beneficiation method provided by the present invention.

[0042] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A beneficiation method for high-sulfur, low-copper copper sulfide ore containing secondary copper, characterized in that: The following steps are involved: S1. Grinding: Grinding the copper sulfide ore into pulp, adding an organic polyphosphonic acid as a pulp conditioner during the grinding process; S2 mixed flotation: The pulp prepared in S1 is mixed with a flotation agent and subjected to three flotation steps, and the coarse concentrate obtained by the three flotation steps is collected; S3. Copper-sulfur separation flotation: The coarse concentrate obtained from the three flotation steps is first regrinded, during which a pyrite combination depressant is added. The resulting pulp is then subjected to copper-sulfur separation flotation, and the concentrate obtained from this separation flotation is the copper concentrate. The pyrite combination depressant is a mixture of calcium oxide, hydrogen peroxide, high molecular weight organic matter, and a synergist, and the amount of pyrite combination depressant added is 500-1500 g / t. 矿石 .

2. The mineral processing method according to claim 1, wherein: The high molecular organic matter is any one or more of sodium humate, dextrin, and tannin; and the synergist is magnesium silicate.

3. The mineral processing method according to claim 2, wherein: The calcium oxide, hydrogen peroxide, high molecular organic matter and synergist are mixed in a mass ratio of (20-50):(10-25):(1-5):(5-10).

4. The mineral processing method according to claim 1, wherein: In the step S1, the ore is ground until the ore particles with a particle size of less than 0.074 mm account for more than 60% of the total ore mass content.

5. The mineral processing method according to claim 1, wherein: In step S1, the organic polyphosphonic acid is any one or more of hydroxyethylidene-1,1-diphosphonic acid HEDP, aminotrimethylenephosphonic acid ATMP, and diethylenetriaminepentamethylenephosphonic acid HTPMP, and the addition amount is 50-150g / t 矿石 .

6. The mineral processing method according to claim 1, wherein: In step S2, the flotation reagent includes a collector and a foaming agent. The collector is a combination of xanthate and ethiocarbamate in a mass ratio of 2:1, and the foaming agent is No. 2 oil. The amount of the flotation reagent is 20 to 100 / t 矿石 .

7. The mineral processing method according to claim 1, wherein: In step S3, the regrinding operation is performed until the ore particles with a particle size of less than 0.045 mm account for more than 70% of the total ore mass content.

8. The mineral processing method according to claim 1, wherein: In step S3, before the copper-sulfur separation flotation is carried out on the regrinded pulp, a collector is added, wherein the collector is ethylthiocarbamate, and the addition amount is 20-100 / t 矿石 .

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