A combined inhibitor of lead-zinc oxide ore in lead-zinc sulfide tailings and its application

Abstract

The present invention relates to a combined inhibitor for lead-zinc oxide ore in lead-zinc sulfide tailings and its application, belonging to the technical field of lead-zinc oxide ore beneficiation. The combined inhibitor comprises sodium fluorosilicate, sodium sulfide, and sodium humate, wherein the mass ratio of the sodium fluorosilicate, sodium sulfide, and sodium humate is 2:5:1. The present invention also includes applying the combined inhibitor to a reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings. The combined inhibitor and reverse flotation process employed in the present invention achieve simultaneous recovery of lead oxide and zinc oxide while ensuring flotation recovery efficiency, and have the advantages of a simple process and low equipment investment.

Description

Technical Field

[0001] The invention belongs to the technical field of lead-zinc oxide ore beneficiation, and in particular relates to a combined inhibitor of lead-zinc oxide ore in lead-zinc sulfide tailings and application thereof. Background Art

[0002] Sulfide-oxidation mixed lead-zinc ore is an important type of lead-zinc ore resource. Sulfide minerals are more hydrophobic than oxide minerals, making their recovery relatively simple. Therefore, the key to the utilization of this type of ore resource lies in the recovery of oxide minerals.

[0003] When recycling mineral resources in sulfide-oxidation mixed lead-zinc ores, a process of first flotation of sulfide minerals and then flotation of oxidized minerals is usually adopted. The recovery of oxidized lead-zinc minerals usually adopts a sulfide flotation process of first lead and then zinc, that is, the sulfide-xanthate method is used to first recover lead oxide, and then the sulfide-fatty amine method is used to recover zinc oxide minerals from the lead oxide tailings. However, the above methods have obvious disadvantages: (1) It is relatively difficult to sulfide oxidized minerals under normal temperature conditions; (2) The application of fatty amines has high requirements for the pulp environment. (3) The oxidized minerals are brittle and have fine embedded particle size; using conventional flotation processes, fine-grained oxidized minerals are easily lost in the tailings. In summary, the use of conventional depressants and flotation processes has the problems of high recovery costs, poor recovery effects, and relatively complex process.

[0004] Therefore, it is necessary to provide a high-separation efficiency combined inhibitor for oxidized lead-zinc ore in lead-zinc sulfide tailings and its application, so as to simplify the process flow, reduce the recovery cost, and at the same time improve the flotation level and comprehensive resource utilization rate of complex and difficult-to-separate lead-zinc ores in my country. Summary of the Invention

[0005] In order to overcome the problems existing in the background technology, the present invention provides a combined inhibitor of lead-zinc oxide ores in lead-zinc sulfide tailings and its application. By using a combined inhibitor with high sorting efficiency and a reverse flotation process, the process flow is simplified, the recovery cost is reduced, and the simultaneous inhibition and recovery of low-grade and difficult-to-select lead-zinc oxide minerals are achieved, thereby improving the flotation level of complex and difficult-to-select lead-zinc ores and the comprehensive utilization rate of resources.

[0006] To achieve the above object, the present invention is implemented through the following technical solutions:

[0007] The combined inhibitor comprises sodium fluorosilicate, sodium sulfide and sodium humate, and the mass ratio of the sodium fluorosilicate, sodium sulfide and sodium humate is 2:5:1.

[0008] The combined inhibitor is applied to the reverse flotation recovery process of oxidized lead-zinc ore in lead-zinc sulfide tailings.

[0009] Preferably, the lead oxide ore is lead alum, and the zinc oxide ore is zinc iron spinel or zincite.

[0010] Preferably, the gangue minerals contained in the lead-zinc sulfide tailings are mainly calcite and dolomite.

[0011] Preferably, the reverse flotation recovery process comprises the following specific steps:

[0012] S1: Grinding the lead-zinc sulfide tailings to obtain a slurry with a grinding fineness of -200 mesh accounting for 90%;

[0013] S2: Sodium fluorosilicate, sodium sulfide, and sodium humate are sequentially added to the slurry obtained in S1 as a combined depressant, and then a collector is added, followed by reverse flotation. After a roughing operation, a roughing concentrate and roughing tailings are obtained. The roughing concentrate is mainly lead-zinc oxide minerals, and the roughing tailings are mainly gangue minerals.

[0014] S3: Add collector to the rougher concentrate obtained in S2, and then perform two scavenging operations, of which the second scavenging is a blank scavenging. The rougher tailings obtained in S2 are combined with the flotation foam obtained by the scavenging to be discarded.

[0015] Preferably, the collector comprises oleic acid and oxidized paraffin soap, and the mass ratio of the oleic acid to the oxidized paraffin soap is 3:1.

[0016] Preferably, in S2, 6000 g / t of combined inhibitor is added per ton of raw ore, including 1500 g / t of ammonium fluorosilicate, 3750 g / t of sodium sulfide, and 750 g / t of sodium humate.

[0017] Preferably, in S2, 300 g / t of collector is added per ton of raw ore.

[0018] Preferably, in S3, 100 g / t of collector is added per ton of raw ore.

[0019] The combined inhibitors of ammonium fluorosilicate, sodium sulfide, and sodium humate of the present invention enable flotation separation of lead-zinc oxide ore from lead-zinc sulfide tailings, primarily relying on the synergistic and reinforcing effects of the three agents. Ammonium fluorosilicate primarily erodes and cleans the minerals, and pretreatment with fluorosilicic acid can increase the relative content of lead and zinc atoms on the surface of the lead-zinc oxide ore, particularly for silicon-containing zinc oxide minerals such as hemimorphite. Furthermore, since lead-zinc sulfide tailings typically contain large amounts of gangue minerals such as calcite and dolomite, the acidity of ammonium fluorosilicate cleanses the calcium and magnesium ions deposited on the surface of the lead-zinc oxide ore, thereby exposing a fresh surface. Sodium sulfide primarily sulfides the target mineral, undergoing a redox reaction with the lead and zinc atoms on the surface of the lead-zinc oxide ore, thereby forming a lead and zinc sulfide film similar to that of the lead-zinc sulfide ore. The pretreatment with ammonium fluorosilicate further enhances the effects of sodium sulfide. The addition of sodium humate will react with the lead sulfide and zinc sulfide films produced by the action of sodium sulfide, and physical and chemical adsorption will occur on their surface to further form a covering layer of macromolecular organic matter, thereby increasing the floatability difference between oxidized lead-zinc ore and gangue minerals such as calcite under the fatty acid system.

[0020] The flotation of lead-zinc oxide minerals from traditional lead-zinc sulfide tailings uses a sulfide-positive flotation process that first adds lead and then zinc. Specifically, the lead oxide minerals are first floated using a sulfide-xanthate method, and then the zinc oxide minerals are recovered from the lead oxide tailings using a sulfide-fatty amine method. During the separation process, corresponding inhibitors are added to suppress the floating of gangue minerals. In the positive flotation process, factors such as the type of collector can produce adverse effects such as excessive flotation foam, significantly impacting the flotation recovery effect. The reverse flotation process of the present invention uses a combined inhibitor to suppress the floating of lead-zinc oxide minerals, while using a collector to float gangue minerals. This is the opposite of the floating and floating inhibitory substances in the traditional positive flotation process, and is therefore called a reverse flotation process. The present invention improves the sorting effect by applying the combined inhibitor to the reverse flotation process, particularly having a beneficial effect on the flotation effect of low-grade lead-zinc oxide minerals.

[0021] Beneficial effects of the present invention:

[0022] 1. The reverse flotation process employed in the present invention offers advantages over conventional flotation processes for lead and zinc oxide minerals, such as a simpler process and reduced equipment investment. Conventional flotation processes for lead and zinc oxide minerals typically utilize a sulfide-xanthate method to preferentially recover lead oxide, followed by a sulfide-fatty amine method to further recover zinc oxide. The reverse flotation process employed in the present invention enables the simultaneous recovery of both lead and zinc oxide.

[0023] 2. The present invention adopts a combined inhibitor with high sorting efficiency and strong adaptability to fluctuations in ore properties to ensure the flotation recovery effect of lead-zinc oxide minerals.

[0024] 3. The combined inhibitor and reverse flotation process adopted in the present invention realizes the simultaneous recovery of lead oxide and zinc oxide, which has great theoretical and economic value for improving the flotation level and comprehensive resource utilization rate of complex lead-zinc mines in my country. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a process flow chart of the present invention

[0026] Figure 2 This is the traditional flotation process flow chart of lead-zinc oxide ore DETAILED DESCRIPTION

[0027] In order to make the objectives, technical solutions and beneficial effects of the present invention more clear, preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings to facilitate understanding by technicians.

[0028] The raw ore of the present invention is the lead-zinc sulfide tailings of a unit in Yunnan Province. The raw ore contains 0.64% Pb and 1.52% Zn. The lead oxide minerals are mainly cerussite and lead alum, and the zinc oxide minerals are mainly zinc-iron spinel. The gangue mineral content is relatively high, mainly calcite, dolomite, etc.

[0029] Example 1

[0030] The invention adopts a reverse flotation process and uses ammonium fluorosilicate, sodium sulfide and sodium humate as a combined inhibitor of lead-zinc oxide minerals, wherein the mass ratio of ammonium fluorosilicate, sodium sulfide and sodium humate is 2:5:1.

[0031] First, the lead-zinc sulfide tailings are ground to obtain a slurry with a grinding fineness of -200 mesh accounting for 90%; then ammonium fluorosilicate, sodium sulfide, and sodium humate are added to the slurry in sequence, with the total amount added being 6000g / t per ton of raw ore. According to the mass ratio of 2:5:1, the amount of ammonium fluorosilicate is 1500g / t, the amount of sodium sulfide is 3750g / t, and the amount of sodium humate is 750g / t. Then, a collector is added, with the total amount of collector added being 300g / t per ton of raw ore. According to the mass ratio of 3:1, the amount of oleic acid added is 225g / t, and the amount of oxidized paraffin soap added is 75g. / t, followed by reverse flotation operation, after a roughing operation, the gangue mineral roughing tailings and the lead-zinc oxide roughing concentrate are obtained, and then 100g / t of collector is added to the obtained lead-zinc oxide roughing concentrate per ton of original ore. According to the proportion, the amount of oleic acid added is 75g / t, and the amount of oxidized paraffin soap added is 25g / t. Then two scavenging operations are carried out, of which the second is a blank scavenging. After the scavenging is completed, the roughing tailings and the flotation foam generated by the scavenging are combined and the tailings are discarded, and finally a lead-zinc oxide mixed concentrate is obtained. The yield and grade during the experiment are tested, and the results are shown in Table 1.

[0032]

[0033] According to the experimental results in Table 1, it can be seen that the present invention can effectively realize the comprehensive recovery of lead-zinc oxide ore in lead-zinc sulfide tailings. The lead grade in the lead-zinc oxide mixed concentrate is 3.61%, the zinc grade is 12.04%, the lead enrichment ratio is 5.64, and the zinc enrichment ratio is 7.92. This shows that the combined inhibitor of the present invention can effectively realize the separation of lead-zinc oxide minerals and gangue minerals such as calcite, thereby ensuring the flotation effect of lead-zinc oxide minerals.

[0034] Comparative Example 1

[0035] In Comparative Example 1, a traditional direct flotation process and a traditional inhibitor were used to conduct a flotation experiment on lead-zinc oxide minerals on a lead-zinc sulfide tailings ore from a unit in Yunnan Province. The ore contained 0.64% Pb and 1.52% Zn. The lead oxide minerals were mainly cerussite and lead alum, and the zinc oxide minerals were mainly zinc-iron spinel. The gangue mineral content was relatively high, mainly calcite, dolomite, etc.

[0036] First, the lead-zinc sulfide tailings are ground to obtain a slurry with a grinding fineness of -200 mesh and a proportion of 90%; then, sodium sulfide is added to the slurry as an activator for lead oxide, and the addition amount is 1000 g / t per ton of raw ore; then, a collector, butyl yellow, is added, and the addition amount is 75 g / t per ton of raw ore, and the lead oxide scavenging amount is 25 g / t; then, a foaming agent, No. 2 oil, is added, and the addition amount is 20 g / t per ton of raw ore, and the lead oxide scavenging amount is 5 g / t; after one roughing and one scavenging operation, lead oxide concentrate and lead oxide tailings are obtained; sodium sulfide is added to the obtained lead oxide tailings as an activator for zinc oxide to separate the zinc oxide ore, and the addition amount is 5000 g / t per ton of raw ore; sodium hexametaphosphate is added as a gangue mineral inhibitor, and the addition amount is 1200 g / t per ton of raw ore. g / t; then add the collector octadecylamine, the addition amount is calculated based on per ton of raw ore, the roughing amount of zinc oxide is 100 g / t, and the scavenging amount of zinc oxide is 50 g / t. After one roughing and one scavenging operation, zinc oxide concentrate and total tailings are obtained. The results are shown in Table 2.

[0037]

[0038] The experimental results in Table 2 show that the comprehensive recovery of lead-zinc oxide minerals using conventional direct flotation processes and traditional depressants is poor. The lead grade in the lead oxide concentrate is 3.11%, 0.50% lower than that in the present invention; the zinc grade in the zinc oxide concentrate is 6.74%, 5.30% lower than that in the present invention; and the lead and zinc recoveries in the total tailings are 3.21% and 6.22% higher, respectively, than those in the present invention. These high recoveries indicate a significant loss of lead-zinc oxide minerals. On the other hand, the combined yield of lead-zinc oxide concentrate in Comparative Example 1 is 21.85%, 12.48% higher than that in the present invention. This high yield indicates poor separation of lead-zinc oxide minerals from gangue minerals, and also increases subsequent transportation and smelting costs. Finally, the conventional direct flotation process and traditional depressants require numerous roughing and scavenging operations, resulting in a complex process.

[0039] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present invention.

Claims

1. A combined inhibitor of lead-zinc oxide ore in lead-zinc sulfide tailings, characterized by: The combined inhibitor comprises sodium fluorosilicate, sodium sulfide and sodium humate, and the mass ratio of the sodium fluorosilicate, sodium sulfide and sodium humate is 2:5:

1.

2. A reverse flotation recovery process for oxidized lead-zinc ore in lead-zinc sulfide tailings using the combined depressant according to claim 1.

3. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 2, characterized in that: The lead oxide ore is lead alum, and the zinc oxide ore is zinc iron spinel or zincite.

4. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 2, characterized in that: The gangue minerals contained in the lead-zinc sulfide tailings are mainly calcite and dolomite.

5. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 2, characterized in that: The specific steps of the reverse flotation recovery process are as follows: S1: Grinding the lead-zinc sulfide tailings to obtain a slurry with a grinding fineness of -200 mesh accounting for 90%; S2: Sodium fluorosilicate, sodium sulfide, and sodium humate are sequentially added to the slurry obtained in S1 as a combined depressant, and then a collector is added, followed by reverse flotation. After a roughing operation, a roughing concentrate and roughing tailings are obtained. The roughing concentrate is mainly lead-zinc oxide minerals, and the roughing tailings are mainly gangue minerals. S3: Add collector to the rougher concentrate obtained in S2, and then perform two scavenging operations, of which the second scavenging is a blank scavenging. The rougher tailings obtained in S2 are combined with the flotation foam obtained by the scavenging to be discarded.

6. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 5, characterized in that: The collector comprises oleic acid and oxidized paraffin soap, and the mass ratio of the oleic acid to the oxidized paraffin soap is 3:

1.

7. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 5, characterized in that: In S2, 6000g / t of combined inhibitor is added per ton of raw ore, including 1500g / t of ammonium fluorosilicate, 3750g / t of sodium sulfide, and 750g / t of sodium humate.

8. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 5, characterized in that: In S2, 300 g / t of collector is added per ton of raw ore.

9. The reverse flotation recovery process for lead-zinc oxide ore in lead-zinc sulfide tailings according to claim 5, characterized in that: In S3, 100 g / t of collector is added per ton of raw ore.

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