A high-efficiency beneficiation method for comprehensive recovery of fluorite in fluorite-containing high-content flotation tailings
By combining classification, grinding, concentration, flotation, and multi-stage cleaning with strong magnetic separation, the problem of recovering flotation tailings with high fluorite content has been solved, realizing the comprehensive recovery and economic utilization of efficient fluorite resources.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHANGSHA RES INST OF MINING & METALLURGY CO LTD
- Filing Date
- 2023-08-23
- Publication Date
- 2026-06-12
AI Technical Summary
Existing technologies cannot effectively recover flotation tailings with high fluorite content, resulting in resource waste and economic losses. Furthermore, the separation of fluorite from gangue minerals is difficult, and the floatability of fluorite is reduced and the degree of liberation of individual particles is low during the flotation process.
A combined process of classification, grinding, concentration, flotation, multi-stage cleaning and high-intensity magnetic separation is adopted, using ionic fluorite activators and high-efficiency inhibitors, combined with high-gradient high-intensity magnetic separation equipment, to achieve pre-enrichment and efficient separation of fluorite.
This improved the grade and recovery rate of fluorite concentrate, reduced the processing volume and energy consumption, achieved efficient and comprehensive recovery of fluorite resources, and reduced production costs.
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Figure CN117299339B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of mine tailings resource recovery technology, specifically a highly efficient mineral processing method for the comprehensive recovery of fluorite from flotation tailings with high fluorite content. Background Technology
[0002] In existing polymetallic beneficiation plants, the flotation tailings discharged from the plant may contain a high fluorite content (e.g., 20%–30%). Due to limitations in existing fluorite beneficiation technology, it is impossible to economically recover fluorite resources from flotation tailings. Instead, these tailings are directly discharged into tailings ponds, resulting in a significant waste of fluorite resources annually, with potential and direct economic losses reaching hundreds of millions of yuan. Furthermore, this accelerates the filling of tailings ponds, drastically shortens their service life, and becomes a technological bottleneck restricting the high-quality and sustainable development of enterprises.
[0003] Fluorite is difficult to recover from flotation tailings discharged from concentrators, mainly due to the following reasons:
[0004] (1) The mineral composition of the tailings is extremely complex, especially containing a large amount of gangue minerals such as calcite and garnet, and the crystal lattice contains the same Ca as fluorite minerals. 2+ The active sites and the three components have extremely similar surface physicochemical properties during the flotation process, making separation difficult.
[0005] (2) The main purpose of front-end recovery is to add a large amount of water glass and acidified water glass during the mineral flotation recovery process. This repeatedly and strongly inhibits the fluorite mineral, and the surface of the fluorite is severely contaminated and covered by the reagents, which greatly reduces its floatability.
[0006] (3) Due to the characteristics of the continuous intergrowth, the individual organisms are difficult to dissociate. Direct fine grinding is not only energy-intensive and costly, but also causes over-grinding and mud formation of calcite and other fragile and easily ground minerals, which cannot be suppressed in subsequent flotation operations.
[0007] To effectively address the pain points and difficulties faced by mining enterprises and break through the current bottlenecks in mineral processing technology, it is imperative to invent a new, economical, efficient, green, and environmentally friendly mineral processing technology specifically for this type of flotation tailings. Summary of the Invention
[0008] This invention aims to overcome a series of mineral processing technical problems in flotation tailings with high fluorite content, such as poor floatability of fluorite minerals, low liberation degree of fluorite monomers, and difficulty in separating calcium-containing gangue. It provides an efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings, which is economical, efficient, environmentally friendly, produces high-quality fluorite concentrate, and has a high mineral processing recovery rate.
[0009] A highly efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings with high fluorite content, such as... Figure 1 As shown, it includes the following steps:
[0010] a) Classify the flotation tailings to obtain classified overflow slurry and classified sediment;
[0011] b) Grind the graded sand obtained in step a) to obtain a fine grinding slurry;
[0012] c) Mix the graded overflow slurry obtained in step a) with the finely ground slurry in step b) to obtain fluorite pre-selected rough concentrate;
[0013] d) The fluorite pre-selected rough concentrate obtained in step c) is concentrated and dehydrated to obtain concentrated underflow slurry;
[0014] e) Add activator, modifier and collector to the concentrated underflow slurry obtained in step d), stir and then carry out fluorite flotation roughing to obtain fluorite rough concentrate;
[0015] f) Add inhibitor A to the fluorite rough concentrate obtained in step e) for a period of fine selection to remove silicate and carbonate gangue minerals, and obtain fluorite concentrate A;
[0016] g) Add inhibitor B to the fluorite concentrate A obtained in step f) for two-stage decalcification to obtain fluorite concentrate B and middlings A. Middlings A is then returned to the first stage of decalcification.
[0017] h) Add the fluorite concentrate B obtained in step g) to inhibitor C for three-stage refining to improve quality and reduce impurities, and obtain fluorite concentrate C and refined ore B. The refined ore B is returned to the second stage of refining.
[0018] i) The fluorite concentrate C from step h) is subjected to strong magnetic separation to remove impurities, and the resulting non-magnetic product is fluorite concentrate.
[0019] In the above-mentioned mineral processing method, preferably, in step a), the flotation tailings contain 20%–30% fluorite, 10%–30% calcite, and 20%–30% garnet; and the degree of liberation of the fluorite monomers in the flotation tailings is 40%–70%.
[0020] Preferably, in step a), the grading is performed using a hydrocyclone group, and the grading particle size includes one of 0.030mm, 0.038mm, 0.045mm, and 0.075mm; in step b), the grading sand is finely ground using an abrasive mill or a tower mill, so that the mass content of particles with a fineness of -0.038mm in the finely ground slurry is ≥50%.
[0021] Preferably, in step c), the graded overflow slurry obtained in step a) is mixed with the finely ground slurry in step b) and then subjected to a pre-selection tailings removal operation to remove iron-containing silicate minerals and gangue minerals from the flotation tailings, thereby obtaining fluorite pre-selected rough concentrate; the pre-selection tailings removal process includes magnetic separation, heavy media separation or gravity separation, to remove iron-containing silicate minerals and gangue minerals from the flotation tailings in advance, so as to achieve pre-enrichment of fluorite.
[0022] Preferably, in step d), after the finely ground slurry and the graded overflow slurry are mixed, concentrated and dewatered, the mass concentration of the underflow slurry is 25% to 55%, and the mass content of particles with a fineness of -0.038 mm in the underflow slurry accounts for ≥70%.
[0023] In step i), the strong magnetic separation equipment used for impurity removal is a high gradient strong magnetic separator or a superconducting magnetic separator, with a magnetic field strength of 1.0T-5.0T and a strong magnetic separation stage of 1-3 times. After concentration and dehydration, the magnetic product is returned to the grinding stage in step b) for fine grinding and re-selection.
[0024] Preferably, in step e), the activator is an ionic fluorite activator CYNH, specifically comprising the following raw materials in parts by weight: 1-30 parts sodium fluoride, 1-30 parts sodium monofluorophosphate, and 1-100 parts calcium chloride; the modifier comprises one or a combination of several of sodium carbonate, water glass, modified water glass, sodium hexametaphosphate, aluminum sulfate, carboxymethyl cellulose, sodium humate, tannin, tannin, and dextrin; the collector comprises one or a combination of several of oleic acid, sodium oleate, oxidized paraffin soap, dodecyl sulfonic acid / sodium sulfate, talc oil, and CY-O3.
[0025] More preferably, the amount of the ionic fluorite activator CYNH is 600-800 g / t; the modifier is sodium carbonate, and the amount is 400-600 g / t; the collector is CY-O3, and the amount is 400-800 g / t, wherein CY-O3 is obtained by dissolving long-chain fatty acids in a solution with oxidized paraffin soap and ethylene glycol at a weight ratio of 3:0.1-0.5:1-1.5 after saponification; most preferably, the amount of the ionic fluorite activator CYNH is 800 g / t; the modifier is sodium carbonate, and the amount is 400 g / t; the collector is CY-O3, and the amount is 600-800 g / t.
[0026] Preferably, in steps f), g), and h), the first-stage refining comprises at least two refining stages, the second-stage refining comprises at least two refining stages, and the third-stage refining comprises at least three refining stages. The three-stage refining design can significantly remove high-content silicate gangue from the tailings, achieving efficient enrichment of fluorite minerals. This is beneficial for ensuring the fluorite flotation recovery rate, reducing fluorite loss in the middlings during flotation, and decreasing the amount of fluorite fed into the subsequent flotation process, thus helping to control flotation costs.
[0027] Preferably, the inhibitors A, B, and C include one or a combination of several of the following: hydrochloric acid, water glass, sodium hexametaphosphate, aluminum sulfate, carboxymethyl cellulose, dextrin, tannin, tannin, acidified water glass, sodium fluorosilicate, and CYY-01; the acidified water glass is obtained by mixing sulfuric acid and water glass in a mass ratio of 1:4, and CYY-01 comprises the following raw materials in parts by weight: 50-100 parts of polyacrylic acid, 1-30 parts of polyaspartic acid, and 1-20 parts of polymaleic acid.
[0028] More preferably, the inhibitors A and C used are a combination of acidified water glass and sodium fluorosilicate inhibitors; and the inhibitor B used is a combination of hydrochloric acid and CYY-01 inhibitor.
[0029] More preferably, in the combined inhibitor of acidified water glass and sodium fluorosilicate, the amount of acidified water glass is 60-80 g / t, the amount of sodium fluorosilicate is 60-80 g / t, and the most preferred amount is 80 g / t; in the combined inhibitor of hydrochloric acid and CYY-01, the amount of hydrochloric acid is 200-800 g / t, the amount of CYY-01 is 60-80 g / t, and the most preferred amount is 80 g / t.
[0030] Preferably, in step i), the strong magnetic separation equipment used for impurity removal is a high gradient strong magnetic separator or a superconducting magnetic separator, with a magnetic field strength of 1.0T-5.0T, and the number of strong magnetic separation stages is 1-3. After concentration and dehydration, the magnetic product is returned to the grinding stage in step b) for fine grinding and re-selection until the basic monomers are liberated.
[0031] Compared with existing conventional technologies, the present invention has the following beneficial effects:
[0032] 1) The mineral processing method of this invention is designed for flotation tailings discharged from concentrators. It breaks through the limitations of conventional mineral processing technology and obtains good indicators such as CaF2 grade ≥ 95% and CaF2 recovery rate ≥ 83% for fluorite concentrate. In particular, the excellent indicator of CaF2 recovery rate ≥ 90% is obtained in fluorite flotation operation. This invention not only realizes the reduction of tailings resources and the comprehensive utilization of strategic resources, but also achieves efficient comprehensive recovery of fluorite from flotation tailings, which has significant economic benefits. It also provides a new approach and idea for the comprehensive utilization of similar fluorite tailings resources.
[0033] 2) This invention is designed for pre-selection and tailings removal of flotation tailings containing fluorite discharged from the concentrator. It removes gangue minerals such as garnet, which have similar floatability to fluorite, from the tailings, thereby achieving pre-enrichment of fluorite. This not only reduces the amount of grinding and flotation operations, saving energy and reducing consumption, but also simplifies the mineral composition of the flotation feed and improves the flotation operating environment.
[0034] 3) The present invention preferably uses an abrasive mill or a tower mill as the classifying and regrinding equipment for sand settling. The grinding product has a narrow particle size distribution, which can significantly reduce the occurrence of over-grinding and under-grinding.
[0035] 4) In the roughing process, an ionic fluorite high-efficiency activator CYNH is added, which can effectively clean the silicate ions covering the surface of the fluorite minerals, deeply activate and restore the strongly suppressed floatability of fluorite in the tailings.
[0036] 5) In the fine selection process, this invention adds a highly efficient calcite inhibitor CYY-01 in combination with hydrochloric acid, which has the characteristics of good selectivity, strong inhibition ability and high stability. During the flotation process, it only strongly inhibits calcite and is friendly to fluorite without inhibiting it, so as to achieve efficient separation of fluorite and calcite.
[0037] 6) This invention targets undissociated minerals in fluorite flotation concentrate that are adjacent to iron-containing silicates. It employs high-gradient strong magnetic separation or superconducting magnetic separation technology for separation. The low-quality magnetic products are returned to the preceding grinding stage for fine grinding and re-selection, resulting in a single high-quality fluorite concentrate product with high recovery rate. Attached Figure Description
[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0039] Figure 1 This is a process flow diagram of the comprehensive recovery of fluorite from flotation tailings according to the present invention;
[0040] Figure 2 This is a process flow diagram of the comprehensive recovery of fluorite from flotation tailings in a polymetallic beneficiation plant according to Embodiment 1 of the present invention;
[0041] Figure 3 This is a process flow diagram of the comprehensive recovery of fluorite from flotation tailings in a polymetallic beneficiation plant, as shown in Embodiment 2 of the present invention. Detailed Implementation
[0042] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.
[0043] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.
[0044] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.
[0045] The main component of fluorite in this invention is calcium fluoride (CaF2); the main component of calcite is calcium carbonate (CaCO3).
[0046] The activator CYNH, collector CY-03, and inhibitor CYY-01 described in this invention were purchased from Changsha Research Institute of Mining and Metallurgy Co., Ltd., located at No. 966, Lushan South Road, Yuelu District, Changsha City.
[0047] The activator CYNH is a mixture of the following raw materials in parts by weight: 10 parts sodium fluoride, 10 parts sodium monofluorophosphate, and 80 parts calcium chloride.
[0048] The collector CY-03 is prepared by dissolving C18 unsaturated fatty acids, oxidized paraffin soap, and ethylene glycol in a weight ratio of 3:0.3:1 to form a solution.
[0049] The inhibitor CYY-01 is composed of the following raw materials in parts by weight: 70 parts polyacrylic acid, 20 parts polyaspartic acid, and 10 parts polymaleic acid.
[0050] Example 1:
[0051] The present invention relates to a highly efficient mineral processing method for the comprehensive and efficient recovery of fluorite from flotation tailings, the specific details of which are as follows:
[0052] The flotation tailings from a polymetallic beneficiation plant processed in this embodiment have a CaF2 grade of 26.25% and a CaCO3 grade of 17.03%, with fluorite being the main valuable mineral. The tailings contain relatively low levels of metallic minerals, including cassiterite, scheelite, wolframite, bismuthinite, molybdenite, pyrite, limonite, chalcopyrite, pyrrhotite, and magnetite. The non-metallic minerals are primarily fluorite, followed by quartz, feldspar, garnet, and sericite. Specifically, quartz accounts for 12.4% by mass, feldspar 4.5%, mica 11.8%, garnet 22.7%, and calcite 22.3%. The fluorite grain size is uneven, with some coarse pieces reaching approximately 0.15 mm, but generally less than 0.10 mm. About 50% of the fluorite occurs as single specimens, while the remaining portion is closely intergrown with quartz, sericite, and garnet, often exhibiting characteristics of contiguous intergrowths.
[0053] Adopting such Figure 2 The beneficiation method for efficient and comprehensive recovery of fluorite shown below includes the following specific steps:
[0054] a) The flotation tailings containing low-grade fluorite discharged from the concentrator are classified using a hydrocyclone group with a classification particle size of 0.045 mm to obtain a classification overflow slurry and classification sand; the degree of liberation of fluorite monomers in the flotation tailings is 65%.
[0055] b) The graded sand from step a) is finely ground using an abrasive mill to obtain a finely ground slurry with a fineness of -0.038 mm and a particle size content of 67%.
[0056] c) After mixing the graded overflow slurry obtained in step a) with the finely ground slurry in step b) (the slurry fineness is -0.038mm particle size accounts for 82%), a strong magnetic separation process is used for pre-selection and tailings disposal. The yield of the pre-selected fluorite rough concentrate is 81.45%, the CaF2 grade is 29.58%, the CaCO3 grade is 20.13%, the pre-selected tailings yield is 18.55%, and the CaF2 grade is 11.64%.
[0057] d) The fluorite pre-selected rough concentrate from step c) is concentrated and dehydrated to obtain a bottom slurry with a slurry mass concentration of 40%.
[0058] e) Add 400g / t of sodium carbonate as a modifier, 800g / t of fluorite activator CYNH, and 600g / t of fluorite collector CY-03 to the concentrated underflow slurry from step d) and perform flotation to obtain fluorite rough concentrate and roughing tailings.
[0059] f) The fluorite rough concentrate from step e) is subjected to two cleaning processes to remove silicate and carbonate gangue minerals. The first cleaning process uses 80 g / t of acidified water glass (sulfuric acid:water glass mass ratio 1:4) and 80 g / t of sodium fluorosilicate. The second cleaning process uses 80 g / t of acidified water glass (sulfuric acid:water glass mass ratio 1:4) and 80 g / t of sodium fluorosilicate to obtain fluorite concentrate 2. The tailings of concentrate 1 and concentrate 2 are discharged and discarded together with the roughing tailings from step e).
[0060] g) Add 600g / t of hydrochloric acid and 80g / t of calcite high-efficiency inhibitor CYY-01 to the fluorite concentrate 2 from step f) to obtain fluorite concentrate 3. The middle ore 3 is returned to the fine ore 2.
[0061] h) Add 200g / t of hydrochloric acid and 80g / t of calcite high-efficiency inhibitor CYY-01 to the fluorite concentrate 3 from step g) to obtain fluorite concentrate 4. The middle ore 4 is returned to the fine ore 3.
[0062] i) Perform the 5th to 9th refining of fluorite concentrate 4 in step g). Each refining process uses 80 g / t of acidified water glass (sulfuric acid: water glass mass ratio 1:4) and 80 g / t of sodium fluorosilicate as inhibitors. The middlings 5 to middlings 9 are sequentially returned to the previous refining operation to obtain fluorite concentrate 9.
[0063] j) The fluorite concentrate from step i) is subjected to a single separation using a ZH-type flat-ring high-gradient magnetic separator with a magnetic field strength of 2.0T. The magnetic product is low-quality fluorite concentrate, which is returned to the preceding grinding section for fine grinding and further separation after concentration and dehydration. The non-magnetic product is high-quality fluorite concentrate, with a yield of 22.97%, a CaF2 grade of 95.03%, a CaF2 recovery rate of 83.14%, and a CaCO3 grade of 0.95% in the fluorite concentrate.
[0064] Using the mineral processing method of this invention, the CaF2 grade of the concentrate product is increased by 14.62 percentage points compared with the conventional mineral processing process, the CaF2 recovery rate is increased by 45 percentage points compared with the conventional mineral processing process, and the CaCO3 grade in the fluorite concentrate is reduced by 6.73 percentage points. The concentrate quality and production indicators have been significantly improved.
[0065] Example 2:
[0066] The present invention relates to a highly efficient mineral processing method for the comprehensive and efficient recovery of fluorite from flotation tailings, the specific details of which are as follows:
[0067] The flotation tailings from a polymetallic concentrator processed in this embodiment have a CaF2 grade of 31.44% (libration degree of 50%), with fluorite as the main valuable mineral. Gangue minerals mainly include garnet, quartz, mica, calcite, and feldspar, with garnet comprising 22.70% by mass, quartz 13.5% by mass, mica 12.6% by mass, calcite 12.1% by mass, and feldspar 4.5% by mass.
[0068] Adopting such Figure 3 The beneficiation method for efficient and comprehensive recovery of fluorite shown below includes the following specific steps:
[0069] a) The flotation tailings containing fluorite discharged from the concentrator are classified using a hydrocyclone group with a classification particle size of 0.045 mm to obtain a classification overflow slurry and classification sand; the degree of liberation of fluorite monomers in the flotation tailings is 64%.
[0070] b) The graded sand from step a) is finely ground using an abrasive mill to obtain a finely ground slurry with a fineness of -0.038 mm particle size and a mass content of 66%.
[0071] c) After mixing the graded overflow slurry obtained in step a) with the finely ground slurry in step b) (the slurry fineness is -0.038mm particle size accounts for 81.5%), the pre-selection tailings are carried out using a strong magnetic separation process. The yield of the pre-selected fluorite rough concentrate is 82.44%, the CaF2 grade is 35.27%, the CaCO3 grade is 10.68%, the pre-selected tailings yield is 17.56%, and the CaF2 grade is 13.46%.
[0072] d) The fluorite pre-selected rough concentrate from step c) is concentrated and dehydrated to obtain a bottom slurry with a slurry mass concentration of 40%.
[0073] e) Add 400g / t of sodium carbonate as a modifier, 800g / t of fluorite activator CYNH, and 800g / t of fluorite collector CY-03 to the concentrated underflow slurry from step d) and perform flotation to obtain fluorite rough concentrate and roughing tailings.
[0074] f) The fluorite rough concentrate from step e) is subjected to two cleaning processes to remove silicate and carbonate gangue minerals. The first cleaning process uses 80 g / t of acidified water glass (sulfuric acid:water glass mass ratio 1:4) and 80 g / t of sodium fluorosilicate. The second cleaning process uses 80 g / t of acidified water glass (sulfuric acid:water glass mass ratio 1:4) and 80 g / t of sodium fluorosilicate to obtain fluorite concentrate 2. The tailings of concentrate 1 and concentrate 2 are discharged and discarded together with the roughing tailings from step e).
[0075] g) Add 800 g / t of hydrochloric acid and 80 g / t of calcite high-efficiency inhibitor CYY-01 to the fluorite concentrate 2 from step f) to obtain fluorite concentrate 3. The middle ore 3 is returned to the fine ore 2.
[0076] h) Add 400 g / t of hydrochloric acid and 80 g / t of calcite-efficient inhibitor CYY-01 to the fluorite concentrate 3 from step g) to obtain fluorite concentrate 4. The middle ore 4 is returned to the fine ore 3.
[0077] i) Perform the 5th to 7th refining of fluorite concentrate 4 from step g), with each refining inhibitor being 80 g / t of acidified water glass (sulfuric acid: water glass mass ratio 1:4) and 80 g / t of sodium fluorosilicate, to obtain fluorite concentrate 7. The middlings 5 to middlings 7 are returned to the previous refining operation in sequence.
[0078] j) The fluorite concentrate from step i) is subjected to a single separation using a ZH-type flat-ring high-gradient magnetic separator with a magnetic field strength of 2.0T. The magnetic product is low-quality fluorite concentrate, which is returned to the preceding grinding section for fine grinding and further separation after concentration and dehydration. The non-magnetic product is high-quality fluorite concentrate, with a yield of 27.20%, a CaF2 grade of 95.34%, a CaF2 recovery rate of 83.48%, and a CaCO3 grade of 0.71% in the fluorite concentrate.
[0079] Using the mineral processing method of this invention, the CaF2 grade of the concentrate product is increased by 13.06 percentage points compared with the conventional mineral processing process, the CaF2 recovery rate is increased by 38.47 percentage points compared with the conventional mineral processing process, and the CaCO3 grade in the fluorite concentrate is reduced by 5.02 percentage points. The quality and production indicators of the fluorite concentrate have been significantly improved.
[0080] Compared to the magnetic-levitation combined process for fluorite beneficiation and recovery at the Shizhuyuan Dongbo polymetallic beneficiation plant, when the fluorite grade and CaCO3 grade of the feed ore are similar, the beneficiation method of this invention increases the CaF2 grade of the concentrate by 9.33 percentage points and the CaF2 recovery rate by 12.28 percentage points, showing significant advantages in both the quality and production indicators of the fluorite concentrate.
[0081] Comparative Example 1:
[0082] The mineral sample used in this comparative example is the same as that in Example 1, and conventional fluorite flotation process is used for flotation recovery. The specific steps are as follows:
[0083] 1) The flotation tailings are finely ground to a fineness of -0.038mm (90%) using a conventional ball mill and fed into the roughing process;
[0084] 2) In the roughing process, 400 g / t of sodium carbonate, 1000 g / t of water glass, and 400 g / t of oleic acid are added to obtain fluorite rough concentrate and roughing tailings.
[0085] 3) The fluorite rough concentrate from step 2) is subjected to two rounds of fine cleaning and desilication. The inhibitor for fine cleaning 1 is 300g / t of water glass; the inhibitor for fine cleaning 2 is 200g / t of water glass, to obtain fluorite concentrate 2. The middlings 1 and middlings 2 are discharged and discarded together with the roughing tailings from step 2).
[0086] The fluorite concentrate 2 from step 3) is subjected to the 3rd to 8th beneficiation. The beneficiation inhibitor is acidified water glass (sulfuric acid: water glass mass ratio 1:4). The amount of acidified water glass used in a single beneficiation is 100g / t. The middlings 3 to 8 are returned to the previous beneficiation operation in sequence. The yield of fluorite concentrate is 12.45%, the CaF2 grade is only 80.41%, the CaF2 recovery rate is only 38.14%, and the CaCO3 grade in the fluorite concentrate is 7.68%. The concentrate quality is poor, the CaF2 recovery rate is low, and the cost per ton of concentrate is high.
[0087] Comparative Example 2:
[0088] The mineral sample used in this comparative example is the same as that in Example 1, and the flotation process is basically the same as that in Example 1. The only difference is that in this comparative example, acidified water glass (sulfuric acid: water glass mass ratio 1:4) is used instead of CYY-01, a highly efficient calcite inhibitor, in steps g) and h). The dosage of the reagent is 80 g / t. The yield of fluorite concentrate is 25.25%, the CaF2 grade is 83.75%, the CaF2 recovery rate is only 80.55%, and the CaCO3 grade in the fluorite concentrate is as high as 11.43%. It can be seen that the conventional calcite inhibitor acidified water glass has a much lower inhibitory ability than the new calcite inhibitor CYY-01. The CaCO3 grade in the fluorite concentrate is significantly higher than that in Example 1 by 10.48 percentage points, which becomes the main factor affecting the grade and quality of fluorite concentrate.
[0089] Comparative Example 3:
[0090] The mineral sample used in this comparative example is the same as that in Example 2, and conventional fluorite flotation process is used for flotation recovery. The specific steps are as follows:
[0091] 1) Grind the flotation tailings to a fineness of -0.038mm (90%) using a ball mill and feed them into the roughing process;
[0092] 2) In the roughing process, 400 g / t of sodium carbonate, 1000 g / t of water glass, and 500 g / t of collector are added to obtain fluorite rough concentrate and roughing tailings.
[0093] 3) The fluorite rough concentrate from step 2) is subjected to two rounds of fine cleaning and desilication. The inhibitor for fine cleaning 1 is 300g / t of water glass; the inhibitor for fine cleaning 2 is 200g / t of water glass, to obtain fluorite concentrate 2. The middlings 1 and middlings 2 are discharged and discarded together with the roughing tailings from step 2).
[0094] The fluorite concentrate 2 from step 3) is subjected to the 3rd to 7th cleaning processes. The cleaning inhibitor is acidified water glass (sulfuric acid:water glass mass ratio 1:4), and the single dosage of the cleaning inhibitor is 100g / t. The middlings 3 to 7 are sequentially returned to the previous cleaning operation, resulting in a low-grade fluorite concentrate yield of 17.20%, CaF2 grade of 82.28%, CaF2 recovery rate of only 45.01%, and CaCO3 grade of 5.73% in the fluorite concentrate.
[0095] Comparative Example 4:
[0096] The mineral sample used in this comparative example is the same as that in Example 2. The magnetic-float combined process for fluorite beneficiation and recovery of fluorite tailings from the Shizhuyuan Dongbo polymetallic beneficiation plant is adopted. The specific steps are as follows:
[0097] The tailings from the fluorite beneficiation process at the Shizhuyuan Dongbo Polymetallic Beneficiation Plant (CaF2 grade 30.00%, CaCO3 8.50%, slurry concentration 10%, -0.075mm particle size content 70%) are first separated by a high-gradient magnetic separator. Under the conditions of a working magnetic field strength of 0.5T and 200 pulses / minute, the magnetic product yield is 34%, with a CaF2 grade of 12%, which is directly discharged into the tailings dam; the non-magnetic product yield is 66%, with a CaF2 grade of 39.27%, which is fed into an inclined plate thickener to concentrate to a slurry concentration of 30%.
[0098] The concentrated non-magnetic product slurry from step 1) is fed into the fluorite roughing operation. Soda ash 400g / t, water glass inhibitor 4500g / t, and oleic acid collector 650g / t are added for flotation to obtain fluorite rough concentrate and roughing tailings.
[0099] The roughing tailings from step 2) are fed into the scavenging operation 1. The oleic acid collector in scavenging operation 1 is 100g / t, and scavenging concentrate 1 and scavenging tailings 1 are obtained. Scavenging concentrate 1 is returned to the roughing operation, and scavenging tailings 1 are directly discharged into the tailings dam.
[0100] The fluorite rough concentrate from step 2) was subjected to five cleaning processes. The depressant for cleaning processes 1 to 5 was acidified water glass (sulfuric acid:water glass mass ratio 1:3), and the reagent dosages were 300 g / t, 200 g / t, 150 g / t, 100 g / t and 80 g / t, respectively. Middlings 1 was returned to the roughing operation, and middlings 2 to 5 were returned to the previous cleaning operation in sequence. The resulting fluorite concentrate product had a CaF2 grade of 86.01% and a CaF2 recovery rate of 71.20%.
Claims
1. A highly efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings with high fluorite content, characterized in that, Includes the following steps: a) Classify the flotation tailings to obtain classified overflow slurry and classified sediment; b) Grind the graded sand obtained in step a) to obtain a fine grinding slurry; c) Mix the graded overflow slurry obtained in step a) with the finely ground slurry in step b) to obtain fluorite pre-selected rough concentrate; d) The fluorite pre-selected rough concentrate obtained in step c) is concentrated and dehydrated to obtain concentrated underflow slurry; e) Add activator, modifier and collector to the concentrated underflow slurry obtained in step d), stir and then carry out fluorite flotation roughing to obtain fluorite rough concentrate; f) Add inhibitor A to the fluorite rough concentrate obtained in step e) for a first-stage refining process to remove silicate and carbonate gangue minerals, and obtain fluorite concentrate A; g) Add inhibitor B to the fluorite concentrate A obtained in step f) for two-stage decalcification to obtain fluorite concentrate B and middlings A. Middlings A is then returned to the first stage of decalcification. h) Add the fluorite concentrate B obtained in step g) to inhibitor C for three-stage refining to improve quality and reduce impurities, and obtain fluorite concentrate C and refined ore B. The refined ore B is returned to the second stage of refining. i) The fluorite concentrate C from step h) is subjected to strong magnetic separation to remove impurities, and the resulting non-magnetic product is fluorite concentrate; The activator is an ionic fluorite activator CYNH, specifically comprising the following raw materials in parts by weight: 1-30 parts sodium fluoride, 1-30 parts sodium monofluorophosphate, and 1-100 parts calcium chloride; the collector is CY-O3, which is obtained by dissolving long-chain fatty acids, oxidized paraffin soap, and ethylene glycol in a weight ratio of 3:0.1~0.5:1~1.5 to prepare a solution. The inhibitors A and C used are a combination of acidified water glass and sodium fluorosilicate inhibitors; the inhibitor B used is a combination of hydrochloric acid and CYY-01 inhibitor, wherein CYY-01 comprises the following raw materials in parts by weight: 50-100 parts of polyacrylic acid, 1-30 parts of polyaspartic acid, and 1-20 parts of polymaleic acid.
2. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to claim 1, characterized in that, In step a), the flotation tailings contain 20% to 30% fluorite, 10% to 30% calcite, and 20% to 30% garnet; the degree of liberation of the fluorite monomers in the flotation tailings is 40% to 70%.
3. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to claim 1, characterized in that, In step a), the grading is performed using a hydrocyclone group, and the grading particle size includes one of 0.030mm, 0.038mm, 0.045mm, and 0.075mm; in step b), the grading sand is finely ground using an abrasive mill or a tower mill, so that the mass content of particles with a fineness of -0.038mm in the finely ground slurry is ≥50%.
4. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to claim 1, characterized in that, In step c), the graded overflow slurry obtained in step a) is mixed with the finely ground slurry in step b) and then subjected to a pre-selection tailings removal operation to remove iron-containing silicate minerals and gangue minerals from the flotation tailings, to obtain fluorite pre-selected rough concentrate; the pre-selection tailings removal process includes magnetic separation, heavy media separation or gravity separation. In step d), after the finely ground slurry and the graded overflow slurry are mixed, concentrated and dewatered, the mass concentration of the underflow slurry is 25%~55%, and the mass content of particles with a fineness of -0.038mm in the underflow slurry accounts for ≥70%. In step i), the strong magnetic separation equipment used for impurity removal is a high gradient strong magnetic separator or a superconducting magnetic separator, with a magnetic field strength of 1.0T-5.0T and a strong magnetic separation stage of 1-3 times. After concentration and dehydration, the magnetic product is returned to the grinding stage in step b) for fine grinding and re-selection.
5. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to claim 1, characterized in that, In step e), the modifier includes one or a combination of several of the following: sodium carbonate, water glass, modified water glass, sodium hexametaphosphate, aluminum sulfate, carboxymethyl cellulose, sodium humate, tannin, tannin, and dextrin.
6. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to claim 5, characterized in that, The dosage of the ionic fluorite activator CYNH is 600-800 g / t; the modifier is sodium carbonate, and its dosage is 400-600 g / t; the collector is CY-03, and its dosage is 400-800 g / t.
7. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to any one of claims 1-6, characterized in that, The first segment of a selection contains at least two selections, the second segment of a selection contains at least two selections, and the third segment of a selection contains at least three selections.
8. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to any one of claims 1-6, characterized in that, The acidified water glass is obtained by mixing sulfuric acid and water glass in a mass ratio of 1:
4.
9. The efficient mineral processing method for comprehensive recovery of fluorite from flotation tailings according to claim 8, characterized in that, In the combined inhibitor of acidified water glass and sodium fluorosilicate, the amount of acidified water glass is 60-80 g / t and the amount of sodium fluorosilicate is 60-80 g / t; in the combined inhibitor of hydrochloric acid and CYY-01, the amount of hydrochloric acid is 200-800 g / t and the amount of CYY-01 is 60-80 g / t.