Method for strengthening flotation separation of rare earth ore
By treating the recycled water and optimizing the flotation process, the problem of separating rare earth minerals from gangue minerals was solved, resulting in improved grade and recovery rate of rare earth concentrate, simplified process flow, and reduced collector consumption.
Patent Information
- Application Number
- CN202511276772.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-08
- Publication Date
- 2025-11-14
AI Technical Summary
Rare earth minerals and gangue minerals have similar surface properties, which makes flotation separation difficult. In addition, calcium and magnesium ions and residual reagents in the reflux water affect the adsorption of the collector, reducing the grade and recovery rate of rare earth concentrate.
The slurry system was optimized by using reagents A and B to treat the recycled water, combined with oxidation pretreatment and multiple flotation steps, and by using inhibitors, collectors and frothers to expand the difference in floatability between rare earth minerals and gangue minerals.
This will improve the grade and recovery rate of rare earth concentrates, reduce the amount of collectors used, simplify the process flow, and facilitate industrial production.
Smart Images
Figure CN120940083A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of mineral processing technology, and in particular to a method for enhancing the flotation separation of rare earth ores. Background Technology
[0002] Rare earth elements, due to their unique spatial structure and physicochemical properties, are widely used in important fields such as high-end manufacturing, artificial intelligence, aerospace, and national defense, serving as key raw materials for pillar and leading industries and earning the reputation of "industrial vitamins." Baustenite and monazite are the main minerals containing rare earth elements, often occurring in association with gangue minerals such as fluorite and dolomite. Firstly, these gangue minerals have similar surface properties to rare earth minerals, making flotation separation difficult. Secondly, the grinding process of gangue minerals releases large amounts of calcium and magnesium ions, leading to a gradual increase in the unavoidable ion content in the beneficiation reflux water, thus consuming a large amount of flotation reagents. Simultaneously, the large amount of reagent residues in the reflux water can coat the surface of rare earth minerals, preventing collector adsorption and resulting in unsatisfactory grades and recovery rates of rare earth concentrates. Therefore, developing methods to eliminate unavoidable ions and residual flotation reagents in the reflux water, thereby widening the floatability difference between rare earth minerals and calcium-containing gangue minerals and enhancing the separation of rare earth minerals, is of great significance. Summary of the Invention
[0003] To address the aforementioned technical problems in existing technologies, embodiments of the present invention provide a method for enhancing the flotation separation of rare earth ores. The technical solution is as follows:
[0004] A method for enhancing the flotation separation of rare earth ores, the method comprising:
[0005] S1. Add reagent A to the rare earth ore flotation return water, perform initial stirring treatment, and filter to obtain the initial treatment return water and filter residue.
[0006] S2. Add reagent B to the primary treated return water obtained in S1, perform secondary stirring, and filter to obtain secondary treated return water and filter residue.
[0007] S3. After mixing and adjusting the rare earth flotation raw materials with the secondary treatment return water, the mixture undergoes oxidation pretreatment, and finally rare earth flotation is carried out.
[0008] In S1, reagent A is one or more of polyaluminum chloride, polyferric sulfate, and polyacrylamide. The dosage of reagent A is 5-30 g / ton of recycled water, and the initial stirring time is 5-10 min.
[0009] In step S2, reagent B consists of carbon dioxide and hydrogen peroxide, which are used to adjust the pH of the initial treated return water to 5-7. The amount of carbon dioxide added is 0.5-3 kg / ton of return water, and the amount of hydrogen peroxide added is 0.5-2 kg / ton of return water. The secondary stirring time is 10-30 min.
[0010] The rare earth flotation raw material in S3 is one of rare earth ore, iron tailings, or rare earth tailings.
[0011] In S3, the rare earth flotation raw materials and secondary treatment return water are mixed and adjusted to a pulp pH of 8-10, with a solid-liquid ratio of 1:0.2 to 1:2 or the pulp concentration is adjusted to 50%-80%.
[0012] The oxidation pretreatment method in S3 includes ultrasonic treatment and the addition of hydrogen peroxide and / or the introduction of ozone, and the addition of hydrogen peroxide and / or the introduction of ozone and ultrasonic treatment are performed simultaneously.
[0013] The amount of hydrogen peroxide added is 0.3-1 kg / ton of slurry, the amount of ozone added is 0.2-0.8 kg / ton of slurry, and the oxidation pretreatment time is 5-20 min.
[0014] In the rare earth flotation process of S3, inhibitors, collectors and frothers are added sequentially, with an interval of 2 to 5 minutes between additions.
[0015] The inhibitor is a mixture of saline water glass and phytic acid, with a mass ratio of saline water glass to phytic acid of (3-6):(0.1-1); the collector is a mixture of naphthohydroxamic acid and cinnamic hydroxamic acid, with a mass ratio of naphthohydroxamic acid to cinnamic hydroxamic acid of (5-10):(1-3); and the foaming agent is a fatty alcohol foaming agent.
[0016] During the roughing stage of rare earth flotation, the dosage of inhibitor is 1-3 kg / t, the dosage of collector is 0.5-1.5 kg / t, and the dosage of frother is 50-300 g / t.
[0017] Preferably, rare earth flotation is carried out in a process of one roughing, three cleaning, and one scavenging step:
[0018] Roughing: Add inhibitor to the oxidized pretreated slurry and stir for 3 min; add collector and stir for 3 min; add frother pine oil and stir for 2 min to carry out flotation roughing to obtain flotation rough concentrate and roughing tailings.
[0019] Primary cleaning: The rougher concentrate from the flotation process is slurryed to form a primary flotation cleaning pulp; the pH of the pulp is 7-11, and the pulp concentration is 40%-60%; the tailings from the primary flotation cleaning are returned to the rougher flotation process for use as raw material; the amount of reagents used in the primary flotation cleaning is half that used in the rougher flotation process;
[0020] Secondary cleaning: The concentrate from the primary flotation is adjusted to form a secondary flotation cleaning pulp; the pH of the pulp is 7-11, and the pulp concentration is 35%-50%. The tailings from the secondary flotation cleaning are returned to the primary flotation cleaning as raw material; the amount of reagents used in the secondary flotation cleaning is half that used in the primary flotation cleaning.
[0021] Third-stage cleaning: The secondary flotation concentrate is slurry adjusted to form a tertiary flotation cleaning slurry; the pH of the slurry is 7-11, and the slurry concentration is 30%-40%; the tailings from the tertiary flotation cleaning are returned to the secondary flotation cleaning as raw material; the amount of reagents used in the tertiary flotation cleaning is half that used in the secondary flotation cleaning.
[0022] First scavenging: The pH of the flotation roughing tailings slurry is adjusted to 7-11, and the scavenging concentrate is returned to the roughing as raw material. The amount of collector added to the scavenging is one-third of that in the roughing, and the amount of frother is half that in the roughing.
[0023] The grade of the final rare earth concentrate obtained in S3 shall not be less than 60%.
[0024] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following:
[0025] The above-mentioned method can improve the grade and recovery rate of rare earth concentrate; reduce the amount of collector used; and the processing method is simple, easy to operate, and suitable for industrial production. Specific advantages are as follows:
[0026] (1) In the treatment of mineral processing wastewater, the present invention first removes ultrafine particles that are difficult to filter by water treatment agents, and then removes unavoidable ions and residual flotation agents in the wastewater by synergistic treatment with carbon dioxide and hydrogen peroxide, thereby optimizing the flotation slurry system and reducing the consumption of collectors.
[0027] (2) In an alkaline slurry system, trivalent cerium ions on the surface of rare earth minerals are converted into tetravalent cerium with higher and more stable valence by ultrasound combined with ozone or hydrogen peroxide pre-oxidation. Tetravalent cerium has a stronger chelating ability with the collector, while gangue minerals such as fluorite and dolomite with similar floatability are stable, thereby widening the floatability difference between rare earth minerals and gangue minerals.
[0028] (3) This invention has strong adaptability to various ores in the rare earth ore flotation process, requires less reagent, has a simple process flow, and has the potential for large-scale promotion. Attached Figure Description
[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0030] Figure 1 This is a process flow diagram of an enhanced rare earth ore flotation separation method provided in an embodiment of the present invention. Detailed Implementation
[0031] The technical solution of the present invention will now be described with reference to the accompanying drawings.
[0032] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.
[0033] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.
[0034] This invention provides a method for enhancing the flotation separation of rare earth ores. For example... Figure 1 The flowchart shown illustrates a method for enhanced flotation separation of rare earth ores, which may include the following steps:
[0035] S1. Add reagent 1 to the rare earth ore flotation return water, perform initial stirring treatment, and filter to obtain initial treatment return water and filter residue.
[0036] S2. Add reagent 2 to the primary treated return water obtained in S1, perform secondary stirring, and filter to obtain secondary treated return water and filter residue.
[0037] S3. After mixing and adjusting the rare earth flotation raw materials with the secondary treatment return water, the mixture undergoes oxidation pretreatment, and finally rare earth flotation is carried out.
[0038] The following description, in conjunction with specific embodiments, illustrates this point.
[0039] Example 1
[0040] (1) Add reagent 1 (polyferric sulfate and polyacrylamide in a mass ratio of 1:2) to the rare earth ore flotation return water of Baoshan Mining Baiyun Obo Mountain Beneficiation Plant. The dosage is 20g / ton of return water. Stir for 8 minutes, and then filter to obtain the primary treatment return water and filter residue.
[0041] (2) Add reagent 2 (carbon dioxide and hydrogen peroxide) to the primary treated return water. The amount of carbon dioxide added is 2 kg / ton of return water, and the amount of hydrogen peroxide added is 0.9 kg / ton of return water. Adjust the pH of the return water to 6, stir for 15 min, and then filter to obtain secondary treated return water and filter residue.
[0042] (3) Mix the iron tailings with the secondary treatment return water to form a slurry with a slurry concentration of 70%. Add ozone at a rate of 0.6 kg / ton of slurry under ultrasonic conditions to adjust the pH of the slurry to 9.5. The oxidation pretreatment time is 8 min.
[0043] (4) Add 2.0 kg / t of inhibitor (saltified water glass and phytic acid in a mass ratio of 4:0.5) to the oxidized pretreated slurry and stir for 3 min; add 0.9 kg / t of collector (1-hydroxy-2-naphthyl hydroxamic acid and cinnamic hydroxamic acid in a mass ratio of 7:2) and stir for 3 min; add 120 g / t of frother pine oil and stir for 2 min to obtain flotation rough concentrate and rough tailings.
[0044] (5) The rougher concentrate is subjected to three flotation cleaning processes to obtain the flotation concentrate:
[0045] The primary flotation cleaning process involves adjusting the rougher concentrate to form a primary flotation cleaning slurry. The slurry has a pH of 9.5 and a concentration of 48%. The tailings from the primary flotation cleaning process are returned to the rougher flotation process as raw materials. The amount of reagents used in the primary flotation cleaning process is half that used in the rougher flotation process.
[0046] Secondary flotation cleaning: The primary flotation concentrate is adjusted to form a secondary flotation cleaning slurry; the pH of the slurry is 9.5 and the slurry concentration is 45%; the tailings from the secondary flotation cleaning are returned to the primary flotation cleaning as raw materials; the amount of reagents used in the secondary flotation cleaning is half that used in the primary flotation cleaning.
[0047] Third-stage flotation: The concentrate from the second-stage flotation is adjusted to form a third-stage flotation concentrate; the pH of the concentrate is 9 and the concentrate concentration is 38%; the tailings from the third-stage flotation concentrate are returned to the second-stage flotation concentrate as raw material; the amount of reagents used in the third-stage flotation concentrate is half that used in the second-stage flotation concentrate.
[0048] (6) Perform a first flotation scavenging on the rougher flotation tailings to obtain flotation tailings:
[0049] The flotation scavenging process includes the following steps: adjusting the pH of the flotation rougher tailings slurry to 9, returning the scavenging concentrate to the rougher for use as raw material, adding one-third of the collector and half of the frother in the scavenging process.
[0050] Example 2
[0051] (1) Add polyaluminum chloride, polyferric sulfate and polyacrylamide in a ratio of 0.5:0.5:2 to the rare earth ore flotation return water of Baoshan Mining Baogang Plant, and add 15g / ton of return water. Stir for 6 minutes, and then filter to obtain the primary treated return water and filter residue.
[0052] (2) Add carbon dioxide and hydrogen peroxide to the primary treated return water. The amount of carbon dioxide added is 1.5 kg / ton of return water, and the amount of hydrogen peroxide added is 1.1 kg / ton of return water. Adjust the pH of the return water to 5.5, stir for 18 min, and then filter to obtain secondary treated return water and filter residue.
[0053] (3) Mix the dilute tailings with the secondary treatment return water to form a slurry with a slurry concentration of 60%. Under ultrasonic conditions, add 0.4 kg / ton of hydrogen peroxide and 0.3 kg / ton of ozone to adjust the pH of the slurry to 9. The oxidation pretreatment time is 10 min.
[0054] (4) Add 1.5 kg / t of inhibitor (5:0.3 mass ratio of saline water glass and phytic acid) to the oxidized pretreated slurry and stir for 5 min; add 1.1 kg / t of collector (8:1 mass ratio of 2-hydroxy-3-naphthyl hydroxamic acid and cinnamic hydroxamic acid) and stir for 3 min; add 150 g / t of frother pine oil and stir for 2 min to obtain flotation rough concentrate and rough tailings.
[0055] (5) The rougher concentrate is subjected to three flotation cleaning processes to obtain the flotation concentrate:
[0056] The primary flotation cleaning process involves adjusting the rougher concentrate to form a primary flotation cleaning slurry. The slurry has a pH of 10 and a concentration of 45%. The tailings from the primary flotation cleaning process are returned to the rougher flotation process as raw materials. The amount of reagents used in the primary flotation cleaning process is half that used in the rougher flotation process.
[0057] Secondary flotation cleaning: The concentrate from the primary flotation is adjusted to form a secondary flotation cleaning slurry; the pH of the slurry is 9 and the slurry concentration is 40%; the tailings from the secondary flotation cleaning are returned to the primary flotation cleaning as raw materials; the amount of reagents used in the secondary flotation cleaning is half that used in the primary flotation cleaning.
[0058] Third-stage flotation: The concentrate from the second-stage flotation is adjusted to form a third-stage flotation concentrate; the pH of the concentrate is 9 and the concentrate concentration is 35%; the tailings from the third-stage flotation concentrate are returned to the second-stage flotation concentrate as raw material; the amount of reagents used in the third-stage flotation concentrate is half that used in the second-stage flotation concentrate.
[0059] (6) Perform a first flotation scavenging on the rougher tailings to obtain flotation tailings:
[0060] The flotation scavenging process includes the following steps: adjusting the pH of the flotation rougher tailings slurry to 10, returning the scavenging concentrate to the rougher for use as raw material, adding one-third of the collector and half of the frother in the scavenging process.
[0061] Example 3
[0062] (1) Polyacrylamide was added to the rare earth ore flotation return water of a rare earth beneficiation plant in Shandong Province at a dosage of 10g / ton of return water. The mixture was stirred for 5 minutes and then filtered to obtain the primary treatment return water and filter residue.
[0063] (2) Add carbon dioxide and hydrogen peroxide to the primary treated return water. The amount of carbon dioxide added is 0.8 kg / ton of return water, and the amount of hydrogen peroxide added is 1.5 kg / ton of return water. Adjust the pH of the return water to 6.5, stir for 25 min, and then filter to obtain secondary treated return water and filter residue.
[0064] (3) Mix the finely ground rare earth ore with the secondary treatment return water to form a slurry with a slurry concentration of 55%. Add hydrogen peroxide at a rate of 0.9 kg / ton of slurry under ultrasonic conditions, adjust the pH of the slurry to 10, and perform an oxidation pretreatment for 15 min.
[0065] (4) Add 2.0 kg / t of inhibitor (saltified water glass and phytic acid in a mass ratio of 6:0.1) to the oxidized pretreated slurry and stir for 5 min; add 0.8 kg / t of collector (1-naphthoic acid and cinnamic acid in a mass ratio of 5:3) and stir for 3 min; add 120 g / t of frother pine oil and stir for 2 min to obtain flotation rough concentrate and rough tailings.
[0066] (5) The rougher concentrate is subjected to three flotation cleaning processes to obtain the flotation concentrate:
[0067] The primary flotation cleaning process involves adjusting the rougher concentrate to form a primary flotation cleaning slurry. The slurry has a pH of 9.5 and a concentration of 45%. The tailings from the primary flotation cleaning process are returned to the rougher flotation process as raw materials. The amount of reagents used in the primary flotation cleaning process is half that used in the rougher flotation process.
[0068] Secondary flotation cleaning: The primary flotation concentrate is adjusted to form a secondary flotation cleaning slurry; the pH of the slurry is 9.2 and the slurry concentration is 40%; the tailings from the secondary flotation cleaning are returned to the primary flotation cleaning as raw materials; the amount of reagents used in the secondary flotation cleaning is half that used in the primary flotation cleaning.
[0069] Third-stage flotation: The concentrate from the second-stage flotation is adjusted to form a third-stage flotation concentrate; the pH of the concentrate is 9.0 and the concentrate concentration is 36%; the tailings from the third-stage flotation concentrate are returned to the second-stage flotation concentrate as raw material; the amount of reagents used in the third-stage flotation concentrate is half that used in the second-stage flotation concentrate.
[0070] (6) Perform a first flotation scavenging on the rougher tailings to obtain flotation tailings:
[0071] The flotation scavenging process includes the following steps: adjusting the pH of the flotation rougher tailings slurry to 9.5, returning the scavenging concentrate to the rougher for use as raw material, adding one-third of the collector and half of the frother in the scavenging process.
[0072] Comparative Example 1
[0073] The difference from Example 1 is that the untreated recycled water was used directly for slurry preparation and flotation, and the amount of collector was increased to 1.3 kg / t. The results are shown in Table 1.
[0074] Comparative Example 2
[0075] The difference from Example 3 is that the slurry was not pretreated by oxidation and was directly subjected to flotation. The results are shown in Table 1.
[0076] Table 1. Flotation results of the examples and comparative examples
[0077] serial number Rare earth concentrate grade / % Rare earth concentrate recovery rate / % Collector dosage / kg / t Example 1 61.15％ 54.23％ 0.9 Example 2 60.44％ 56.94％ 1.1 Example 3 62.52％ 55.37％ 0.8 Comparative Example 1 58.86％ 53.51％ 1.3 Comparative Example 2 57.77％ 54.28％ 1.0
[0078] As shown in Table 1, compared with Comparative Example 1 and Comparative Example 2, the rare earth concentrate obtained by the processing method of the present invention (Examples 1-3) has a higher grade and recovery rate.
[0079] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A method for enhancing the flotation separation of rare earth ores, characterized in that, The method includes: S1. Add reagent A to the rare earth ore flotation return water, perform initial stirring treatment, and filter to obtain the initial treatment return water and filter residue. S2. Add reagent B to the primary treated return water obtained in S1, perform secondary stirring, and filter to obtain secondary treated return water and filter residue. S3. After mixing and adjusting the rare earth flotation raw materials with the secondary treatment return water, the mixture undergoes oxidation pretreatment, and finally rare earth flotation is carried out.
2. The method for enhanced rare earth ore flotation separation according to claim 1, characterized in that, In S1, reagent A is one or more of polyaluminum chloride, polyferric sulfate, and polyacrylamide. The dosage of reagent A is 5-30 g / ton of recycled water, and the initial stirring time is 5-10 min.
3. The method for enhanced rare earth ore flotation separation according to claim 1, characterized in that, In step S2, reagent B consists of carbon dioxide and hydrogen peroxide, which are used to adjust the pH of the initial treated return water to 5-7. The amount of carbon dioxide added is 0.5-3 kg / ton of return water, and the amount of hydrogen peroxide added is 0.5-2 kg / ton of return water. The secondary stirring time is 10-30 min.
4. The method for enhanced rare earth ore flotation separation according to claim 1, characterized in that, The rare earth flotation raw material in S3 is one of rare earth ore, iron tailings, or rare earth tailings.
5. The method for enhanced rare earth ore flotation separation according to claim 1, characterized in that, In S3, the rare earth flotation raw material is mixed with the secondary treatment return water and the slurry is adjusted to a slurry pH of 8-10 and a slurry concentration of 50%-80%.
6. The method for enhanced rare earth ore flotation separation according to claim 1, characterized in that, The oxidation pretreatment method in S3 includes ultrasonic treatment and the addition of hydrogen peroxide and / or the introduction of ozone, and the addition of hydrogen peroxide and / or the introduction of ozone and ultrasonic treatment are performed simultaneously.
7. The method for enhanced rare earth ore flotation separation according to claim 6, characterized in that, The amount of hydrogen peroxide added is 0.3-1 kg / ton of slurry, the amount of ozone added is 0.2-0.8 kg / ton of slurry, and the oxidation pretreatment time is 5-20 min.
8. The method for enhanced rare earth ore flotation separation according to claim 1, characterized in that, In the rare earth flotation process of S3, inhibitors, collectors and frothers are added sequentially, with an interval of 2 to 5 minutes between additions.
9. The method for enhanced rare earth ore flotation separation according to claim 8, characterized in that, The inhibitor is a mixture of saline water glass and phytic acid, with a mass ratio of saline water glass to phytic acid of (3-6):(0.1-1); the collector is a mixture of naphthohydroxamic acid and cinnamic hydroxamic acid, with a mass ratio of naphthohydroxamic acid to cinnamic hydroxamic acid of (5-10):(1-3); and the foaming agent is a fatty alcohol foaming agent.
10. The method for enhanced rare earth ore flotation separation according to claim 8, characterized in that, During the roughing stage of rare earth flotation, the dosage of inhibitor is 1-3 kg / t, the dosage of collector is 0.5-1.5 kg / t, and the dosage of frother is 50-300 g / t.