Copper-molybdenum bulk concentrate flotation separation combined inhibitor and application thereof

Abstract

The invention discloses a copper-molybdenum bulk concentrate flotation separation combined inhibitor and application thereof, and belongs to the technical field of mineral flotation separation. The combined inhibitor is formed by mixing isomaltose and sodium hexametaphosphate. The method for using the combined inhibitor for flotation separation of the copper-molybdenum bulk concentrate specifically comprises the steps that the copper-molybdenum bulk concentrate is subjected to scrubbing, reagent removal and pulping; a combined inhibitor, a collecting agent and a foaming agent are sequentially added into the ore pulp, primary roughing is conducted, and roughing concentrate and roughing tailings are obtained; the roughing concentrate is subjected to three times of concentration, a combined inhibitor is supplemented in each time of concentration, and copper concentrate is obtained; and the roughing tailings are subjected to two times of scavenging, the collecting agent is supplemented in each time of scavenging, and molybdenum concentrate is obtained. According to the method, the floatability difference of the copper ore and the molybdenum ore is enlarged by inhibiting molybdenum and floating copper, the use of high-toxicity agents can be reduced, meanwhile, copper can be efficiently recycled, the grade of molybdenum concentrate can be guaranteed, and good environmental compatibility and industrial application prospects are achieved.

Description

Technical Field

[0001] This invention relates to the field of mineral flotation separation technology, specifically to a combined inhibitor for the flotation separation of copper-molybdenum mixed concentrate and its application. Background Technology

[0002] Copper sulfide minerals (such as chalcopyrite and molybdenite) are important minerals for extracting copper and molybdenum metals. They often coexist closely in porphyry deposits. In industrial production, copper and molybdenum mixed concentrates are usually obtained by bulk flotation first, and then separated by selective inhibition. However, since the natural floatability of the two is similar, it is often difficult to obtain ideal separation indicators if effective depressants are not introduced to expand the flotation difference.

[0003] Currently, the most widely used process is copper suppression and molybdenum flotation, with common copper depressants including sulfides, cyanides, and phosphoroxane reagents. Although separation can be achieved, this method suffers from drawbacks such as high toxicity, environmental pollution, high reagent dosage, poor selectivity, and high cost, making it difficult to meet the demands of green environmental protection and low-cost development. In particular, for ores with high molybdenum and low copper grades, using copper suppression and molybdenum flotation does not conform to the flotation principle of more suppression and less flotation, easily leading to problems such as mechanical inclusions, high foam viscosity, and low pulp concentration. However, the types of depressants suitable for molybdenum suppression and copper flotation are currently limited, and existing molybdenum suppression technologies often have insufficient selectivity or poor suppression effects when separating mixed concentrates of chalcopyrite and molybdenite.

[0004] Therefore, developing a novel molybdenum-inhibiting combined inhibitor that is low in toxicity, environmentally friendly, highly selective, and cost-effective is of great industrial significance for the effective separation of copper-molybdenum mixed concentrates, especially under resource conditions of high molybdenum and low copper. Summary of the Invention

[0005] To address the problems of high reagent toxicity, environmental pollution, insufficient selectivity, and poor separation effect under high molybdenum and low copper resource conditions in existing copper-molybdenum mixed concentrate separation methods, the present invention aims to provide a combined inhibitor for the flotation separation of copper-molybdenum mixed concentrate. The combined inhibitor is composed of isomaltose and sodium hexametaphosphate, wherein the mass ratio of isomaltose to sodium hexametaphosphate is 1:1 to 2:1.

[0006] Another object of the present invention is to provide an application of a combined inhibitor in the flotation separation of copper-molybdenum mixed concentrates, specifically including the following steps: (1) The copper-molybdenum mixed concentrate was scrubbed and de-treated to prepare a slurry.

[0007] (2) Add a combination of inhibitor, collector and frother to the slurry in sequence, and obtain rough concentrate and rough tailings after one roughing process.

[0008] (3) The rough concentrate obtained in step (2) is subjected to three fine treatments, and a combination inhibitor is added in each fine treatment to obtain copper concentrate.

[0009] (4) The rough tailings obtained in step (2) are subjected to two scavenging processes, with a collector added each time, to obtain molybdenum concentrate from the scavenged tailings.

[0010] Preferably, the amount of the combined inhibitor used in step (2) of the present invention is 1000-1500 g / t.

[0011] Preferably, the collector used in step (2) of the present invention is butyl xanthate, and the amount of collector used is 50-60 g / t.

[0012] Preferably, in step (2) of the present invention, the foaming agent selected is No. 2 oil, and the amount of foaming agent is 15~25g / t.

[0013] Preferably, in the three selection operations of step (3) of the present invention, the amount of combined inhibitor used in selection operation I is 500-750 g / t; the amount of combined inhibitor used in selection operation II is 250-370 g / t; and the amount of combined inhibitor used in selection operation III is 100-200 g / t.

[0014] Preferably, in step (3) of the present invention, a foaming agent needs to be added during the selection process. The foaming agent is No. 2 oil, and the amount of foaming agent is 8~12g / t.

[0015] Preferably, the collector in step (4) of the present invention is butyl xanthate, and the amount of collector used in scavenging operation I is 25-30 g / t; the amount of collector used in scavenging operation II is 12-15 g / t.

[0016] Preferably, in step (4) of the present invention, a foaming agent needs to be added during the scavenging operation. The foaming agent is No. 2 oil, and the amount of foaming agent used in the scavenging operation is 8~12g / t.

[0017] Compared with the prior art, the present invention provides a combined depressant for the flotation separation of copper-molybdenum mixed concentrate and its application, which has the following beneficial effects: (1) In the separation of copper and molybdenum minerals, the commonly used process route is to suppress copper and float molybdenum, which is prone to problems such as mechanical inclusion, high foam viscosity and low pulp concentration. This invention follows the flotation principle of suppressing more and floating less. For high molybdenum and low copper minerals, the synergistic effect of isomaltose and sodium hexametaphosphate effectively blocks the approach of subsequent collectors, reduces mechanical entrainment and other problems in the flotation process, can prioritize the recovery of copper concentrate, and can reasonably recover molybdenum through scavenging, thereby improving the level of comprehensive utilization.

[0018] (2) Good process adaptability: The combined inhibitor of the present invention has a better effect under weakly alkaline to neutral conditions, reduces the use of alkaline agents such as lime, avoids scaling and circulating water problems, has good compatibility with other agents, and will not damage the foam system.

[0019] (3) Superior economic efficiency: The two components in the combined inhibition of the present invention are widely available, low in cost, simple in preparation process, and require moderate amount, which can significantly reduce the cost of mineral processing.

[0020] (4) Green and environmentally friendly: Isomaltose is a widely available biodegradable organic compound that is safe and non-toxic; Sodium hexametaphosphate is a commonly used inorganic polyphosphate that is environmentally friendly and avoids the use of highly toxic agents such as cyanide and phosphorus, significantly reducing the risk of environmental pollution. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the flotation process used in the embodiments of the present invention. Detailed Implementation

[0022] 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.

[0023] Example 1 In this embodiment, isomaltose and sodium hexametaphosphate are used as a combined depressant for the flotation of a copper-molybdenum mixed concentrate. The flotation process flow is as follows: Figure 1 As shown, the chemical composition of a copper-molybdenum mixed concentrate is: Mo content 32.68%, Cu content 9.80%. A closed-circuit test was conducted, and the specific steps are as follows: (1) The copper-molybdenum mixed concentrate is scrubbed and de-treated in a mill, and then the slurry required for flotation is prepared (limestone is added to adjust the pH of the slurry to 7-8).

[0024] (2) Add 1000g / t of combined inhibitor (isomaltose and sodium hexametaphosphate in a mass ratio of 1:1), 60g / t of collector (butyl xanthate) and 25g / t of frother (2# oil) to the slurry in sequence based on the dry weight of each ton of copper-molybdenum mixed concentrate. After thorough stirring, carry out aeration flotation to obtain rougher concentrate and rougher tailings.

[0025] (3) The rough concentrate obtained in step (2) is subjected to three cleaning processes. In cleaning process I, 500 g / t of combined inhibitor and 12 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In cleaning process II, 250 g / t of combined inhibitor is added. In cleaning process III, 100 g / t of combined inhibitor is added. After stirring and flotation in each stage, copper concentrate is finally obtained. The tailings from the three cleaning processes are returned to the previous stage in sequence.

[0026] (4) The roughing tailings obtained in step (2) are subjected to two scavenging operations. In scavenging operation I, 30 g / t of collector (butyl xanthate) and 12 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In scavenging operation II, 15 g / t of collector (butyl xanthate) is added. After stirring and flotation in each stage, the final scavenged tailings are molybdenum concentrate. The concentrates from the two scavenging operations are returned to the previous stage operation in sequence.

[0027] The closed-circuit flotation test results of this embodiment are shown in Table 1.

[0028] Example 2 In this embodiment, isomaltose and sodium hexametaphosphate are used as a combined depressant for the flotation of a copper-molybdenum mixed concentrate. The flotation process flow is as follows: Figure 1 As shown, the chemical composition of a copper-molybdenum mixed concentrate is: Mo content 32.68%, Cu content 9.80%. A closed-circuit test was conducted, and the specific steps are as follows: (1) The copper-molybdenum mixed concentrate is scrubbed and de-treated in a mill, and then the slurry required for flotation is prepared (limestone is added to adjust the pH of the slurry to 7-8).

[0029] (2) Add 1200g / t of combined inhibitor (isomaltose and sodium hexametaphosphate in a mass ratio of 1.5:1), 55g / t of collector (butyl xanthate) and 20g / t of frother (2# oil) to the slurry in sequence based on the dry weight of each ton of copper-molybdenum mixed concentrate. After thorough stirring, carry out aeration flotation to obtain rougher concentrate and rougher tailings.

[0030] (3) The rough concentrate obtained in step (2) is subjected to three cleaning processes. In cleaning process I, 600 g / t of combined inhibitor and 10 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In cleaning process II, 300 g / t of combined inhibitor is added. In cleaning process III, 150 g / t of combined inhibitor is added. After stirring and flotation in each stage, copper concentrate is finally obtained. The tailings from the three cleaning processes are returned to the previous stage in sequence.

[0031] (4) The roughing tailings obtained in step (2) are subjected to two scavenging operations. In scavenging operation I, 27 g / t of collector (butyl xanthate) and 10 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In scavenging operation II, 13 g / t of collector (butyl xanthate) is added. After stirring and flotation in each stage, the final scavenged tailings are molybdenum concentrate. The concentrates from the two scavenging operations are returned to the previous stage operation in sequence.

[0032] The closed-circuit flotation test results of this embodiment are shown in Table 1.

[0033] Example 3 In this embodiment, isomaltose and sodium hexametaphosphate are used as a combined depressant for the flotation of a copper-molybdenum mixed concentrate. The flotation process flow is as follows: Figure 1 As shown, the chemical composition of a copper-molybdenum mixed concentrate is: Mo content 38.71%, Cu content 5.79%. A closed-circuit test was conducted, and the specific steps are as follows: (1) The copper-molybdenum mixed concentrate is scrubbed and de-treated in a mill, and then the slurry required for flotation is prepared (limestone is added to adjust the pH of the slurry to 8-9).

[0034] (2) Add 1400 g / t of combined inhibitor (isomaltose and sodium hexametaphosphate in a mass ratio of 2:1), 50 g / t of collector (butyl xanthate) and 15 g / t of frother (2# oil) to the slurry in sequence based on the dry weight of each ton of copper-molybdenum mixed concentrate. After thorough stirring, carry out aeration flotation to obtain rougher concentrate and rougher tailings.

[0035] (3) The rough concentrate obtained in step (2) is subjected to three cleaning processes. In cleaning process I, 700 g / t of combined inhibitor and 8 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In cleaning process II, 350 g / t of combined inhibitor is added. In cleaning process III, 175 g / t of combined inhibitor is added. After stirring and flotation in each stage, copper concentrate is finally obtained. The tailings from the three cleaning processes are returned to the previous stage in sequence.

[0036] (4) The roughing tailings obtained in step (2) are subjected to two scavenging operations. In scavenging operation I, 25 g / t of collector (butyl xanthate) and 8 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In scavenging operation II, 12 g / t of collector (butyl xanthate) is added. After stirring and flotation in each stage, the final scavenged tailings are molybdenum concentrate. The concentrates from the two scavenging operations are returned to the previous stage operation in sequence.

[0037] The closed-circuit flotation test results of this embodiment are shown in Table 1.

[0038] Example 4 In this embodiment, isomaltose and sodium hexametaphosphate are used as a combined depressant for the flotation of a copper-molybdenum mixed concentrate. The flotation process flow is as follows: Figure 1 As shown, the chemical composition of a copper-molybdenum mixed concentrate is: Mo content 40.29%, Cu content 5.44%. A closed-circuit test was conducted, and the specific steps are as follows: (1) The copper-molybdenum mixed concentrate is scrubbed and de-treated in a mill, and then the slurry required for flotation is prepared (limestone is added to adjust the pH of the slurry to 8-9).

[0039] (2) Add 1500g / t of combined inhibitor (isomaltose and sodium hexametaphosphate in a mass ratio of 2:1), 60g / t of collector (butyl xanthate) and 20g / t of frother (2# oil) to the slurry in sequence based on the dry weight of each ton of copper-molybdenum mixed concentrate. After thorough stirring, carry out aeration flotation to obtain rougher concentrate and rougher tailings.

[0040] (3) The rough concentrate obtained in step (2) is subjected to three cleaning processes. In cleaning process I, 750 g / t of combined inhibitor and 10 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In cleaning process II, 370 g / t of combined inhibitor is added. In cleaning process III, 200 g / t of combined inhibitor is added. After stirring and flotation in each stage, copper concentrate is finally obtained. The tailings from the three cleaning processes are returned to the previous stage in sequence.

[0041] (4) The roughing tailings obtained in step (2) are subjected to two scavenging operations. In scavenging operation I, 30 g / t of collector (butyl xanthate) and 10 g / t of frother (2# oil) are added sequentially based on the dry weight of each ton of copper-molybdenum mixed concentrate. In scavenging operation II, 15 g / t of collector (butyl xanthate) is added. After stirring and flotation in each stage, the final scavenged tailings are molybdenum concentrate. The concentrates from the two scavenging operations are returned to the previous stage operation in sequence.

[0042] The closed-circuit flotation test results of this embodiment are shown in Table 1.

[0043] Comparative Example 1 This comparative example is intended to be compared with Example 2. Its process flow, mineral samples used, and types and amounts of other reagents except for the inhibitor are exactly the same as those in Example 1. The difference is that the mass ratio of isomaltose and sodium hexametaphosphate in the combined inhibitor used in this comparative example is 3:1.

[0044] The closed-circuit test results for this comparative example are shown in Table 1.

[0045] Comparative Example 2 This comparative example is intended to be compared with Example 2. Its process flow, mineral samples used, and types and amounts of other reagents except for the inhibitor are exactly the same as those in Example 1. The difference is that the mass ratio of isomaltose and sodium hexametaphosphate in the combined inhibitor used in this comparative example is 4:1.

[0046] The closed-circuit test results for this comparative example are shown in Table 1.

[0047] Comparative Example 3 This comparative example is intended to be compared with Example 2. Its process flow, mineral samples used, and types and amounts of other reagents except for the inhibitor are exactly the same as those in Example 1. The difference is that the mass ratio of isomaltose and sodium hexametaphosphate in the combined inhibitor used in this comparative example is 5:1.

[0048] The closed-circuit test results for this comparative example are shown in Table 1.

[0049] Comparative Example 4 This comparative example is intended to be compared with Example 2. Its process flow, mineral samples used, and types and amounts of reagents other than the inhibitor are exactly the same as those in Example 1. The difference is that the inhibitor used in this comparative example is isomaltose in an amount equal to that of the combined inhibitor, and sodium hexametaphosphate is not used.

[0050] The closed-circuit test results for this comparative example are shown in Table 1.

[0051] Comparative Example 5 This comparative example is intended to be compared with Example 2. Its process flow, mineral samples used, and types and amounts of reagents other than the inhibitor are exactly the same as those in Example 1. The difference is that the inhibitor used in this comparative example is sodium hexametaphosphate in an amount equal to that of the combined inhibitor, and isomaltose is not used.

[0052] The closed-circuit test results for this comparative example are shown in Table 1.

[0053] Comparative Example 6 This comparative example is intended to be compared with Example 2. Its process flow, mineral samples used, and types and amounts of reagents other than inhibitors are exactly the same as those in Example 1. The difference is that this comparative example uses sodium hydrosulfide as an inhibitor, and the inhibitor dosage in the roughing stage is adjusted to 1500 g / t; the inhibitor dosages in the cleaning stages I, II, and III are adjusted to 1000 g / t, 500 g / t, and 200 g / t, respectively.

[0054] The closed-circuit test results for this comparative example are shown in Table 1.

[0055] Comparative Example 7 This comparative example is intended to compare with Example 2. Its process flow, mineral samples used, and the types and amounts of reagents other than the inhibitor are completely identical to those in Example 1. The difference is that this comparative example uses dextrin as the inhibitor. The inhibitor dosage in the roughing stage is adjusted to 1500 g / t; the inhibitor dosages in the cleaning stages I, II, and III are adjusted to 1000 g / t, 500 g / t, and 200 g / t, respectively. The closed-circuit test results of this comparative example are shown in Table 1.

[0056] Table 1 The results of closed-circuit flotation tests of copper-molybdenum mixed concentrates in Examples 1-4 and Comparative Examples 1-7 of this invention are shown in Table 1. In Examples 1-4, after flotation using the combined inhibitor system of this invention, the Cu content of the obtained molybdenum concentrate was only 0.55%-1.57%, indicating that the floatability of molybdenite was effectively suppressed. At the same time, the Mo content of the copper concentrate was less than 10%, and the Cu recovery rate was above 90%. Chalcopyrite could be preferentially floated. The system of this invention can simultaneously ensure high copper recovery rate and high molybdenum concentrate purity under weakly alkaline conditions, and the separation effect is stable and reliable.

[0057] In contrast, the Cu recovery rates in Comparative Examples 1–3 all decreased significantly, indicating that excessive inhibition impaired flotation selectivity. In Comparative Example 4, when only isomaltose was used, both the molybdenum concentrate grade and recovery rate decreased, indicating that the inhibition ability of a single organic component was insufficient. In Comparative Example 5, when only sodium hexametaphosphate was used, the inhibition effect was extremely weak, and molybdenum and copper were hardly effectively separated. In Comparative Example 6, a sodium hydrosulfide system was used, which could partially inhibit molybdenum, but both the molybdenum concentrate grade and copper recovery rate decreased, and the reagent was corrosive and toxic. In Comparative Example 7, when dextrin was used as an inhibitor, the molybdenum concentrate grade dropped to 46.79%, and the molybdenum recovery rate was only 76.13%, indicating poor inhibition selectivity, and significant cross-flotation of copper and molybdenum still occurred.

[0058] The comprehensive comparative results show that the isomaltose-sodium hexametaphosphate combined inhibitor system of the present invention exhibits a good synergistic effect. Through the surface adsorption of isomaltose and the complexation and dispersion effect of sodium hexametaphosphate, a stable hydrophilic film is formed on the surface of molybdenite, thereby significantly reducing the floatability of molybdenite. The surface of chalcopyrite responds weakly to the system and maintains good hydrophobicity, allowing copper minerals to float preferentially. The system of the present invention achieves a low-consumption, high-efficiency, and environmentally friendly molybdenum suppression and copper flotation separation effect.

[0059] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A combined depressant for the flotation separation of copper-molybdenum mixed concentrate, characterized in that, The combined inhibitor is composed of isomaltose and sodium hexametaphosphate, wherein the mass ratio of isomaltose to sodium hexametaphosphate is 1:1 to 2:

1.

2. The application of the combined inhibitor as described in claim 1 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, Specifically, the following steps are included: (1) The copper-molybdenum mixed concentrate was scrubbed and de-treated to prepare a slurry; (2) Add a combination of inhibitor, collector and frother to the slurry in sequence, and obtain rough concentrate and rough tailings after one roughing process; (3) The rough concentrate obtained in step (2) is subjected to three fine treatments, with a combination inhibitor added each time, to obtain copper concentrate. (4) The rough tailings obtained in step (2) are subjected to two scavenging processes, with a collector added each time, to obtain molybdenum concentrate from the scavenged tailings.

3. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, The slurry pH in step (1) is 7-9.

4. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, The dosage of the coarsely selected combination inhibitor in step (2) is 1000-1500 g / t.

5. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, The collector used in step (2) is butyl xanthate, and the amount of collector used is 50-60 g / t.

6. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, In step (2), the foaming agent used in the rough selection is No. 2 oil, and the amount of foaming agent used is 15~25g / t.

7. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, In the three selection operations described in step (3), the dosage of the combined inhibitor in selection operation I is 500-750 g / t; the dosage of the combined inhibitor in selection operation II is 250-370 g / t; and the dosage of the combined inhibitor in selection operation III is 100-200 g / t.

8. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, Step (3) Selecting I requires the addition of a foaming agent. The foaming agent is No. 2 oil, and the amount of foaming agent used is 8~12g / t.

9. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, The collector in step (4) is butyl xanthate. The amount of collector used in scavenging operation I is 25-30 g / t; the amount of collector used in scavenging operation II is 12-15 g / t.

10. The application of the combined inhibitor according to claim 2 in the flotation separation of copper-molybdenum mixed concentrate, characterized in that, Step (4) A foaming agent needs to be added during the scavenging operation I. The foaming agent is No. 2 oil, and the amount of foaming agent used in the scavenging operation I is 8~12g / t.

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