A method for separating depressed pyrite and arsenopyrite from copper-sulfur separation tailings
By concentrating and naturally stacking the copper-sulfur separation tailings, and using the acidic substances generated by pyrite itself to clean the surface film, the problem of difficult separation between suppressed pyrite and arsenopyrite was solved, achieving efficient and low-cost separation and obtaining high-purity sulfur concentrate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ANHUI UNIVERSITY OF TECHNOLOGY
- Filing Date
- 2026-03-24
- Publication Date
- 2026-06-09
AI Technical Summary
In existing technologies, pyrite and arsenopyrite are difficult to separate efficiently during the copper-sulfur separation process, and activators are often added, which can also activate the arsenopyrite and affect the separation effect.
By concentrating and naturally stacking the copper-sulfur separation tailings, controlling the stacking time, and utilizing the acidic substances generated by pyrite itself to clean the surface film, the separation of suppressed pyrite and arsenopyrite can be achieved without the need for additional activators.
This method achieves efficient separation of suppressed pyrite and arsenopyrite, simplifies process operation, reduces costs, improves separation efficiency, and yields high-purity sulfur concentrate.
Smart Images
Figure CN122164558A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of non-ferrous metal recycling technology, and more specifically, relates to a method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings. Background Technology
[0002] Arsinitic pyrite and pyrite are the most widely distributed primary arsenic-bearing minerals and iron sulfide minerals in metallic deposits, often closely associated with minerals such as copper, lead, and zinc. In the copper-sulfur separation process, depending on the ore properties, processes such as copper-preferred flotation or mixed copper-sulfur flotation are selected, all of which face the common problem of copper-sulfur separation. To achieve selective flotation separation of copper and sulfur, the selection and addition of depressants are particularly important. Currently, high-alkali flotation processes using lime as a depressant are widely used both domestically and internationally for copper-sulfur separation due to their mature technology and good separation effect.
[0003] The efficient separation and recovery of suppressed pyrite and arsenopyrite is one of the technical challenges faced by scientists. Unsuppressed arsenopyrite and pyrite have similar crystal structures, resulting in similar surface properties and flotation behavior, which is the main reason for their difficulty in separation. Pyrite suppressed by lime forms hydrophilic substances such as iron hydroxyl compounds and various calcium-containing precipitates on its surface, while suppressed arsenopyrite forms a dense, strongly hydrophilic, insoluble calcium-arsenate precipitate and a hydrophilic film of iron hydroxyl compounds on its surface. Currently, to achieve flotation separation of suppressed pyrite and arsenopyrite, it is usually necessary to first add an activator to break down these hydrophilic films, allowing pyrite to re-expose a fresh surface, thus de-suppressing and activating the pyrite. However, this inevitably activates the arsenopyrite as well. Because the floatability of de-suppressed and activated pyrite and arsenopyrite is similar to that of unsuppressed pyrite and arsenopyrite, adding arsenopyrite inhibitors makes it difficult to achieve efficient separation of pyrite and arsenopyrite and obtain qualified arsenic-containing sulfur concentrate.
[0004] Therefore, it is necessary to further develop advanced new technologies applicable to the separation of suppressed pyrite and arsenopyrite in copper-sulfur separation tailings, in order to overcome the technical bottleneck that the existing technology activates suppressed arsenopyrite while de-activating suppressed pyrite, thereby achieving effective separation of suppressed pyrite and arsenopyrite. Summary of the Invention
[0005] To address the technical problem in existing technologies that typically require the addition of activators to de-activate suppressed pyrite in order to achieve separation of suppressed pyrite and arsenopyrite, this application provides a method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings. This invention achieves effective separation of suppressed pyrite and arsenopyrite by concentrating and naturally stockpiling copper-sulfur separation tailings containing both suppressed pyrite and arsenopyrite, without the need for the addition of activators for de-activation.
[0006] To achieve the above objectives, the technical solution provided by the present invention is as follows:
[0007] This invention provides a method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings, comprising: The copper-sulfur separation tailings slurry is concentrated, precipitated, and stockpiled. The stockpiling conditions include a stockpiling time of 70-200 hours. The copper-sulfur separation tailings after concentration, precipitation and stockpiling are subjected to slurry conditioning treatment. Collector and frother are added to the copper-sulfur separation tailings after slurry conditioning, and a roughing process is carried out to obtain rough concentrate and rough tailings respectively. No activator is added to activate the suppressed pyrite before the first roughing process. The roughing tailings are subjected to scavenging treatment, and the roughing concentrate is subjected to fine treatment to obtain qualified sulfur concentrate and flotation tailings, respectively.
[0008] To address the problem that existing technologies typically require the addition of additional activators to de-activate suppressed pyrite in order to separate it from arsenopyrite, and that arsenopyrite is inevitably activated as well, thus affecting the separation efficiency, the inventors of this application unexpectedly discovered during their research that by naturally stacking the copper-sulfur separation tailings slurry under certain conditions for a certain period of time, efficient separation of suppressed pyrite and arsenopyrite can be achieved without the need for additional activators to de-activate the suppressed pyrite. In other words, this application overcomes the inherent technical knowledge of those skilled in the art, and its process is simple to operate and has low cost.
[0009] Specifically, during the predetermined storage period of copper-sulfur separation tailings, pyrite, whose surface is covered with hydrophilic films such as Ca(OH)2, FeOOH, and Fe(OH)3, will cleanse the surface film from the inside out due to the generation of acidic substances. Simultaneously, although arsenopyrite also generates some acidic substances during the same storage period, its amount is far less than that of pyrite, insufficient to remove the hydrophilic substances (such as Ca(OH)2, FeOOH, Fe(OH)3, and insoluble arsenates such as Ca3(AsO4)2 and CaHAsO4) interwoven on the surface of arsenopyrite. This results in a significant difference in the surface properties of the two materials, thus enabling their effective separation and recovery.
[0010] However, it should be noted that the control of storage conditions, especially the storage time, is crucial for ensuring the efficient separation of suppressed pyrite and arsenopyrite in this application. When the predetermined storage time is exceeded, the amount of acidic substances generated increases. While removing the hydrophilic substances from the surface of pyrite, these substances also diffuse into the tailings environment and act on the surface of the arsenopyrite particles. At this point, the acidic substances gradually remove the hydrophilic coating layer from the outside in, exposing fresh surfaces and forming new active sites. This process causes the surface properties of pyrite and arsenopyrite to become similar, making effective separation difficult.
[0011] Furthermore, the moisture content of the copper-sulfur separation tailings after concentration, precipitation, and stockpiling is 20-40%; the stockpiled copper-sulfur separation tailings are then slurry-adjusted, and the slurry concentration after slurry-adjustment is 30%-45%.
[0012] Furthermore, the sulfur content of the copper-sulfur separation tailings to be separated is 20%-29%, and the arsenic content is 4%-8%.
[0013] Furthermore, in the roughing process, the collector comprises sodium butyl xanthate and sodium ethyl xanthate, the mixing mass ratio of sodium butyl xanthate and sodium ethyl xanthate is 1:1-1:5, the concentration of the collector is 1%-5%, and the dosage is 30-120g / t slurry. And / or the foaming agent is pine oil, with a dosage of 20-80 g / t slurry.
[0014] More preferably, the scavenging process includes two scavenging processes. In the first scavenging process, the amounts of collector and frother are 30-70 g / t and 15-30 g / t, respectively, and in the second scavenging process, the amounts of collector and frother are 10-40 g / t and 10-30 g / t, respectively.
[0015] Furthermore, the scavenged concentrate obtained after the first scavenging is returned to the roughing operation, and the scavenged concentrate obtained after the second scavenging is returned to the first scavenging operation.
[0016] More preferably, the refining process includes two refining operations: the refined tailings obtained after the first refining are returned to the roughing operation, and the refined tailings obtained after the second refining are returned to the first refining operation.
[0017] Furthermore, the qualified sulfur concentrate obtained has a sulfur content greater than 38.00% and an arsenic content less than 0.30%.
[0018] Furthermore, during the first refining operation, an arsenopyrite inhibitor is added to the roughing concentrate. The arsenopyrite inhibitor comprises any one or any combination of chitosan, carboxymethyl cellulose, and fulvic acid, with a concentration of 3.00%-9.00% and an addition amount of 100-300 g / t. No reagents are added during the second refining operation.
[0019] More preferably, when the arsenopyrite inhibitor is formulated from chitosan and carboxymethyl cellulose, the mass ratio of chitosan to fulvic acid is (1-4):(1-2); When the arsenopyrite inhibitor is formulated from chitosan and fulvic acid, the mixing mass ratio is (1-6):(1-3); When the acrid inhibitor is formulated from carboxymethyl cellulose and fulvic acid, the mixing mass ratio is (1-3):(1-5); When the arsenopyrite inhibitor is formulated from chitosan, carboxymethyl cellulose and fulvic acid, the mass ratio of the mixture is (1-2):(1-4):(1-5).
[0020] Compared with the prior art, the technical solution provided by this invention has the following advantages: (1) The present invention concentrates and stores copper-sulfur separation tailings containing suppressed pyrite and arsenopyrite for a certain period of time, thereby eliminating the need to add an additional activator to de-suppress and activate the suppressed pyrite, thus achieving effective separation of suppressed pyrite and arsenopyrite. This breaks the inherent understanding in the field and can effectively avoid the difficulty in separating the two due to the large-scale activation of suppressed arsenopyrite, greatly improving the separation effect.
[0021] (2) This invention optimizes and controls the concentration and storage conditions of copper-sulfur separation tailings, especially the storage time, which is more conducive to further ensuring the separation effect of suppressed pyrite and arsenopyrite.
[0022] (3) In the roughing operation, the present invention does not require the addition of arsenopyrite inhibitors. Only 100-300 g / t of inhibitor is added during the first fine selection. The dosage is low and much lower than the dosage of arsenic inhibitors used in the prior art.
[0023] (4) The scope of application of this application is wide. For copper-sulfur separation feed containing 20.00-29.00% sulfur and 4.00-8.00% arsenic, the process of this invention can be used to obtain sulfur concentrate with arsenic grade less than 0.30% and sulfur content greater than 38.00%. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation
[0025] To further understand the present invention, specific embodiments are now described in detail. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this disclosure for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts of this disclosure.
[0026] Furthermore, the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. For example, the terms "comprising," "including," etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.
[0027] Furthermore, regarding the parameter value range in the claims of this application, it means that the parameter can take any value within the stated value range, or any specific value within the stated value range. However, due to space limitations, only some values are given in the following embodiments, but the scope of protection of this application is not limited to the specific values in the embodiments. For example, the storage time of 70-200 hours means that the storage time can take any value range within this range, such as 70-200 hours, 70-90 hours, 100-150 hours, 120-200 hours, etc., and can also take any specific value within the above range, such as 70 hours, 80 hours, 100 hours, 1200 hours, 180 hours, 200 hours, etc.
[0028] Example 1 This embodiment provides a process for separating suppressed pyrite without activation and arsenopyrite flotation in copper-sulfur separation tailings, combined with... Figure 1 As shown, it includes the following steps: 1. The copper-sulfur separation tailings slurry containing 22.46% sulfur and 4.79% arsenic was concentrated, precipitated, and stockpiled for 80 hours. The moisture content of the copper-sulfur separation tailings after concentration, precipitation, and stockpiling was 25%. 2. The copper-sulfur separation tailings that have been stored for 80 hours are pumped into mixing tank 1 for slurry preparation. The slurry concentration after preparation is 30.00%. 3. Pump the slurry from mixing tank 1 into mixing tank 2. No activator needs to be added. Add 80g / t collector (5.00% concentration) and 30g / t pine oil to mixing tank 2 and stir for 5 minutes. In this embodiment, the collector contains sodium butyl xanthate and sodium ethyl xanthate, and the mass ratio of sodium butyl xanthate to sodium ethyl xanthate is 1:1. 4. Pump the slurry in mixing tank 2 into the flotation machine for roughing to obtain roughing concentrate and roughing tailings; 5. After adding 40g / t collector (5.00%) and 15g / t pine oil to the roughing tailings box, perform the first scavenging to obtain the first scavenging concentrate and scavenging tailings; 6. After adding 20g / t of collector (5.00%) and 10g / t of pine oil to the tailings box of the first scavenging, a second scavenging is carried out to obtain the second scavenging concentrate and tailings; 7. Prepare an arsenic inhibitor with a concentration of 3.00% by mixing chitosan and carboxymethyl cellulose at a mass ratio of 1:1. Add 240 g / t of the arsenic inhibitor to the roughing concentrate box for the first cleaning process to obtain the first cleaned concentrate and the cleaned tailings. 8. The concentrate is further refined without the addition of any reagents to obtain a sulfur concentrate containing 0.231% arsenic and 38.46% sulfur.
[0029] Example 2 This embodiment provides a process for separating suppressed pyrite without activation and arsenopyrite by flotation in copper-sulfur separation tailings, including the following steps: 1. The copper-sulfur separation tailings containing 27.32% sulfur and 6.84% arsenic were concentrated, precipitated, and stockpiled for 120 hours. The moisture content of the copper-sulfur separation tailings after concentration, precipitation, and stockpiling was 30%. 2. Pump the copper-sulfur separation tailings that have been stockpiled for 120 hours into mixing tank 1 for slurry preparation. The slurry concentration after preparation is 40.00%. 3. Pump the slurry in mixing tank 1 into mixing tank 2. No activator needs to be added. Add 100g / t collector with a concentration of 5.00% and 40g / t pine oil to mixing tank 2 and stir for 7 minutes. In this embodiment, the collector contains sodium butyl xanthate and sodium ethyl xanthate, and the mixing mass ratio of sodium butyl xanthate and sodium ethyl xanthate is 1:2. 4. Pump the slurry in mixing tank 2 into the flotation machine for roughing to obtain roughing concentrate and roughing tailings; 5. After adding 50g / t collector (5.00% concentration) and 20g / t pine oil to the roughing tailings box, perform the first scavenging to obtain the first scavenging concentrate and scavenging tailings; 6. After adding 25g / t collector (5.00%) and 10g / t pine oil to the tailings box of the first scavenging, a second scavenging is carried out to obtain the second scavenging concentrate and tailings; 7. Prepare an arsenic inhibitor with a concentration of 5.00% by mixing chitosan, carboxymethyl cellulose and fulvic acid in a mass ratio of 1:2:4. Add 150g / t of the arsenic inhibitor to the roughing concentrate box for the first cleaning process to obtain the first cleaned concentrate and the cleaned tailings. 8. The concentrate is further refined without the addition of any reagents to obtain a sulfur concentrate containing 0.252% arsenic and 39.23% sulfur content.
[0030] Example 3 This embodiment provides a process for separating suppressed pyrite without activation and arsenopyrite by flotation in copper-sulfur separation tailings, including the following steps: 1. The copper-sulfur separation tailings containing 28.47% sulfur and 7.82% arsenic were concentrated, precipitated, and stockpiled for 180 hours. The moisture content of the copper-sulfur separation tailings after concentration, precipitation, and stockpiling was 22%. 2. Pump the stockpiled copper-sulfur separation tailings into mixing tank 1 for slurry preparation, adjusting the slurry concentration to 30.00%; 3. Pump the slurry from mixing tank 1 into mixing tank 2. No activator needs to be added. Add 120g / t collector (5.00% concentration) and 50g / t pine oil to mixing tank 2 and stir for 10 minutes. In this embodiment, the collector contains sodium butyl xanthate and sodium ethyl xanthate, and the mixing mass ratio of sodium butyl xanthate and sodium ethyl xanthate is 1:3. 4. Pump the slurry in mixing tank 2 into the flotation machine for roughing to obtain roughing concentrate and roughing tailings; 5. After adding 60g / t collector (5.00%) and 20g / t pine oil to the roughing tailings box, perform the first scavenging to obtain the first scavenging concentrate and scavenging tailings; 6. After adding 30g / t collector (5.00%) and 10g / t pine oil to the tailings box of the first scavenging, a second scavenging is carried out to obtain the second scavenging concentrate and tailings; 7. Prepare an arsenic inhibitor with a concentration of 4.00% by mixing chitosan and fulvic acid at a mass ratio of 2:3. Add 200g / t of the arsenic inhibitor to the roughing concentrate box for the first cleaning process to obtain the first cleaned concentrate and the cleaned tailings. 8. The concentrate is further refined without the addition of any reagents to obtain a sulfur concentrate containing 0.271% arsenic and 40.38% sulfur content.
[0031] Example 4 This embodiment provides a process for separating suppressed pyrite without activation and arsenopyrite by flotation in copper-sulfur separation tailings, including the following steps: 1. The copper-sulfur separation tailings containing 25.17% sulfur and 5.83% arsenic were concentrated, precipitated, and stockpiled for 100 hours. The moisture content of the copper-sulfur separation tailings after concentration, precipitation, and stockpiling was 38%. 2. Pump the stockpiled copper-sulfur separation tailings into mixing tank 1 for slurry preparation. The slurry concentration after preparation is 45.00%. 3. Pump the slurry in mixing tank 1 into mixing tank 2. No activator needs to be added. Add 90g / t collector with a concentration of 5.00% and 30g / t pine oil to mixing tank 2 and stir for 8 minutes. In this embodiment, the collector contains sodium butyl xanthate and sodium ethyl xanthate, and the mixing mass ratio of sodium butyl xanthate and sodium ethyl xanthate is 1:1. 4. Pump the slurry in mixing tank 2 into the flotation machine for roughing to obtain roughing concentrate and roughing tailings; 5. After adding 50g / t of collector with a concentration of 5.00% and 20g / t of pine oil to the roughing tailings box, the first scavenging is carried out to obtain the first scavenging concentrate and scavenging tailings; 6. After adding 25g / t collector (5.00%) and 10g / t pine oil to the tailings box of the first scavenging, a second scavenging is carried out to obtain the second scavenging concentrate and tailings; 7. Prepare an arsenic inhibitor with a concentration of 3.00% by mixing carboxymethyl cellulose and fulvic acid at a mass ratio of 3:1. Add 180 g / t of the arsenic inhibitor to the roughing concentrate box for the first cleaning process to obtain the first cleaned concentrate and the cleaned tailings. 8. The concentrate is further refined without the addition of any reagents to obtain a sulfur concentrate containing 0.223% arsenic and 37.65% sulfur.
Claims
1. A method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings, characterized in that, include: The copper-sulfur separation tailings slurry to be treated is concentrated, precipitated and stockpiled. The stockpiling conditions include a stockpiling time of 70-200 hours. The copper-sulfur separation tailings after concentration, precipitation and stockpiling are subjected to slurry conditioning treatment. Collector and frother are added to the copper-sulfur separation tailings after slurry conditioning, and a roughing process is carried out to obtain rough concentrate and rough tailings respectively. No activator is added to activate the suppressed pyrite before the first roughing process. The roughing tailings are subjected to scavenging treatment, and the roughing concentrate is subjected to fine treatment to obtain qualified sulfur concentrate and flotation tailings, respectively.
2. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 1, characterized in that, The moisture content of the copper-sulfur separation tailings after concentration, sedimentation and stockpiling is 20-40%; the stockpiled copper-sulfur separation tailings are then slurry-adjusted, and the slurry concentration after slurry-adjustment is 30%-45%.
3. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 1, characterized in that, The sulfur content of the tailings to be separated from copper and sulfur is 20%-29%, and the arsenic content is 4%-8%.
4. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 1, characterized in that, In the roughing process, the collector includes sodium butyl xanthate and sodium ethyl xanthate, the mixing mass ratio of sodium butyl xanthate and sodium ethyl xanthate is 1:1-1:5, the concentration of the collector is 1%-5%, and the dosage is 30-120g / t slurry. And / or the foaming agent is pine oil, with a dosage of 20-80 g / t slurry.
5. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to any one of claims 1-4, characterized in that, The scavenging process includes two scavenging processes. In the first scavenging process, the dosage of collector and frother is 30-70 g / t and 15-30 g / t, respectively. In the second scavenging process, the dosage of collector and frother is 10-40 g / t and 10-30 g / t, respectively.
6. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 5, characterized in that, The scavenged concentrate obtained after the first scavenging is returned to the roughing operation, and the scavenged concentrate obtained after the second scavenging is returned to the first scavenging operation.
7. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to any one of claims 1-4, characterized in that, The refining process includes two refining operations. The refined tailings obtained after the first refining operation are returned to the roughing operation, and the refined tailings obtained after the second refining operation are returned to the first refining operation.
8. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 7, characterized in that, The qualified sulfur concentrate obtained has a sulfur content greater than 38.00% and an arsenic content less than 0.30%.
9. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 7, characterized in that, During the first cleaning operation, arsenopyrite inhibitor is added to the roughing concentrate. The arsenopyrite inhibitor contains any one or any combination of chitosan, carboxymethyl cellulose, and fulvic acid, with a concentration of 3.00%-9.00% and an addition amount of 100-300 g / t. No reagents are added during the second cleaning operation.
10. The method for separating suppressed pyrite and arsenopyrite in copper-sulfur separation tailings according to claim 9, characterized in that, When the arsenopyrite inhibitor is formulated from chitosan and carboxymethyl cellulose, the mixing mass ratio is (1-4):(1-2); When the arsenopyrite inhibitor is formulated from chitosan and fulvic acid, the mixing mass ratio is (1-6):(1-3); When the acrid inhibitor is formulated from carboxymethyl cellulose and fulvic acid, the mixing mass ratio is (1-3):(1-5); When the arsenopyrite inhibitor is formulated from chitosan, carboxymethyl cellulose and fulvic acid, the mass ratio of the mixture is (1-2):(1-4):(1-5).