Beneficiation method for low-grade fluorite ore containing magnesium carbonate type

Abstract

The application provides a beneficiation method for a low-grade fluorite ore containing magnesium carbonate, and belongs to the technical field of fluorite beneficiation. The application obtains a pre-concentrated mineral by grading and pre-throwing waste treatment on the fluorite raw ore; the pre-concentrated mineral is subjected to grinding treatment, and a first ore slurry is prepared after adding water; a flotation agent is used for the flotation operation of the first ore slurry; the flotation agent comprises a compounded depressant and a compounded adjusting agent, the compounded depressant comprises aluminum sulfate, sodium hexametaphosphate, tannic acid, citric acid and sodium alginate, and the compounded adjusting agent comprises calcium lignosulfonate, hydroxyethyl cellulose and potassium dichromate. Through the above mode, the beneficiation method for the low-grade fluorite ore containing magnesium carbonate provided by the application can utilize the synergistic effect between a specific beneficiation process and an improved reagent system, cancel the acid leaching operation, and improve the fluorite recovery rate and grade with a simpler process and lower reagent cost, so that the application has a very high industrial application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluorite beneficiation, and particularly relates to a beneficiation method for a magnesium carbonate type low-grade fluorite ore. BACKGROUND

[0002] Fluorite is an indispensable raw material source for fluorine chemical industry and a non-metallic mineral resource with strategic significance. While the demand for fluorine chemical products in the economic market is increasing, the resources of high-grade and easily selected single fluorite ore are becoming increasingly scarce. Therefore, efficient development and utilization of low-grade and difficult-to-select fluorite ore is imminent. At present, in the utilization process of low-grade fluorite ore resources, the beneficiation of magnesium carbonate type low-grade fluorite ore is difficult. Many beneficiation researchers have conducted a large amount of research on the beneficiation technology of carbonate type fluorite ore mainly composed of calcite, but there is less research on magnesium carbonate type low-grade fluorite ore mainly composed of (iron) dolomite. In many fluorite ore deposits in northern China, the reserves of magnesium carbonate type low-grade fluorite ore mainly composed of (iron) dolomite are very rich. Therefore, the research on magnesium carbonate type low-grade fluorite ore is of great significance.

[0003] Since (iron) dolomite and fluorite belong to calcium-containing non-metallic minerals, their hardness, density and floatability are similar, and they are both easy-to-mill minerals, resulting in a complex beneficiation process of magnesium carbonate type low-grade fluorite ore. At present, the method of “desliming-flotation-acid leaching” is mainly used to recover magnesium carbonate type low-grade fluorite ore. The ore is first crushed and screened, then the oversize minerals are physically deslimed by using ordinary cyclones and sedimentation, and the gangue minerals with smaller specific gravity are pre-removed as waste. The removed concentrate and undersize minerals are sequentially subjected to grinding, flotation and acid leaching operations to finally produce qualified fluorite concentrate. However, through laboratory comparison and verification of the current beneficiation method and combined with production data analysis, it is found that the current method has a low recovery rate of raw ore resources. The ordinary cyclone loses a lot of fine fluorite ore while separating the argillaceous gangue. Moreover, the separation effect of (iron) dolomite and fluorite is poor, and the fluorite concentrate obtained by flotation must be further treated (acid leaching with a large amount of hydrochloric acid) to form fluorite concentrate products that are easy to sell. However, since a large amount of hydrochloric acid is needed for acid leaching, the service life of the equipment is seriously shortened, and the backwater of acid leaching is difficult to treat, resulting in a sharp increase in the operation and management cost of the beneficiation plant.

[0004] Therefore, it is still necessary to design an improved beneficiation method for magnesium carbonate type low-grade fluorite ore to solve the above problems. SUMMARY

[0005] In view of the technical problems in the background art, the present application provides a beneficiation method for a low-grade fluorite ore containing magnesium carbonate type, aiming to solve the technical problems of low recovery rate, poor separation effect on fluorite and other minerals, and the need for acid leaching in the existing beneficiation method.

[0006] The embodiment of the present application provides a beneficiation method for a low-grade fluorite ore containing magnesium carbonate type, comprising the following steps:

[0007] S1. The fluorite raw ore is classified and pre-throwing waste, and a pre-enriched mineral is obtained;

[0008] S2. The pre-enriched mineral is ground and treated, and water is added to prepare a first ore slurry;

[0009] S3. The first ore slurry is subjected to flotation operation by using a flotation reagent; the flotation reagent comprises a compounded inhibitor and a compounded modifier; the compounded inhibitor comprises aluminum sulfate, sodium hexametaphosphate, tannic acid, citric acid and sodium alginate; and the compounded modifier comprises calcium lignosulfonate, hydroxyethyl cellulose and potassium dichromate.

[0010] In the technical scheme of the embodiment of the present application, the fluorite raw ore is first classified and pre-throwing waste, which improves the grade of the raw ore entering the flotation, reduces the grinding amount, and reduces the beneficiation cost; on this basis, the present application optimizes the flotation reagent, adopts the compounded reagent, combines inorganic inhibitors and organic modifiers, so that it can specifically inhibit dolomite and calcite in the low-grade fluorite ore containing magnesium carbonate type, fully plays the compounded synergistic effect between the reagents, reduces the heterogeneous condensation between fluorite and carbonate particles, strengthens the dispersion degree of the ore slurry, reduces the adsorption amount of the collector on the surface of the fine particle carbonate mineral, and improves the inhibition effect on silicate minerals while inhibiting carbonate minerals, so as to accelerate the floating rate of fluorite, and then improve the selectivity of fluorite collector.

[0011] In some embodiments, the compounded inhibitor comprises 20-50% aluminum sulfate, 10-30% sodium hexametaphosphate, 5-20% tannic acid, 5-20% citric acid, and 5-20% sodium alginate by mass percentage.

[0012] In this embodiment, the flotation reagents also include the inhibitor acidified water glass and the collector saponified oleic acid. In the flotation system using saponified oleic acid as the collector, (ferro)dolomite and calcite exhibit strong negative charge on their surfaces in the pulp, allowing for electrostatic or micellar adsorption. Saponified oleic acid, on the other hand, exists as ions or ion-molecule associations. The adsorption of saponified oleic acid on the calcite surface is significantly affected by pH, but it exhibits strong adsorption of fluorite across the entire pH range. Therefore, in a weakly acidic environment, the separation of fluorite from gangue minerals such as (ferro)dolomite and calcite can be effectively achieved. In the flotation reagent system provided in this embodiment, the acidified water glass and the aluminum sulfate and citric acid in the compound inhibitors provide an acidic environment for the pulp system. The collector (RCOO)2... 2- and RCOO - Anions react chemically with carbonate gangue minerals such as dolomite to form precipitates, making dolomite and calcite difficult to be collected by collectors.

[0013] More specifically, in weakly acidic conditions, the Al produced by the hydrolysis of aluminum sulfate 3+ With Alm(OH) n 3m-n It exists in the form of Alm(OH), which can clean the surface of minerals, accelerate the dissolution of some carbonate minerals in fluorite, and does not affect the surface electrical properties of fluorite. n 3m-n It mainly adsorbs onto the surfaces of dolomite, calcite, and barite via hydrogen bonding electrostatic forces, thereby changing their surface charge and inhibiting the floatability of these gangue minerals. In the compound inhibitor component, sodium hexametaphosphate can induce competitive adsorption of various phosphate ions on the surface of carbonate minerals in the pulp, generating calcium phosphate and thus inhibiting the adsorption of carbonate minerals. Furthermore, the dispersing effect of sodium hexametaphosphate can effectively reduce heterogeneous flocculation of fine-grained fluorite minerals and gangue minerals during flotation, allowing the collector to act more effectively on the active sites on the fluorite mineral surface. The phenolic hydroxyl groups and carboxyl groups generated from the hydrolysis of tannic acid in the compound inhibitor component can react with the calcium ions on the mineral surface. 2+ A hydroxyl complex Ca(OH) is formed in solution. + Complexes or chelates form, and the reaction products precipitate on the mineral surface. Calcite usually has a stronger solubility than fluorite, and the resulting hydroxyl complex CaOH... + More, CaOH +The complexing agent has a larger adsorption capacity, thereby achieving selective inhibition of vein minerals. The large number of polar groups in tannic acid, citric acid and sodium alginate in the complexing inhibitor are adsorbed on the surface of (iron) dolomite, calcite and other carbonate vein minerals in the ore slurry, and less on the surface of fluorite minerals, thereby causing differences in the wettability of fluorite and vein minerals. These polar groups have hydrogen bond effects with water molecules, thereby increasing the hydrophilicity of the surface of the vein minerals and achieving the purpose of selective inhibition. Because sulfide minerals are associated with fluorite deposits, they are a harmful component in the flotation of fluorite and usually have an adverse effect on the grade of fluorite concentrate produced in continuous production. Therefore, the complexing inhibitor contains an additional sodium alginate component, which has chelating groups such as hydroxyl and carboxyl groups in its molecules. These groups can undergo chelation reactions on the surface of metal minerals and increase the hydrophilicity of the surface. They also have a certain inhibitory effect on fine-grained silicates, thereby achieving the purpose of synergistic cooperation with other components of the complexing inhibitor.

[0014] In the above manner, the synergistic effect of the various raw materials in the complexing inhibitor can be fully utilized to improve the inhibitory effect on carbonate minerals and silicates and the selectivity of the fluorite collector, thereby improving the recovery rate and grade of fluorite.

[0015] In some embodiments, the complexing modifier comprises 20% to 60% calcium lignosulfonate, 5% to 40% hydroxyethyl cellulose and 5% to 40% potassium dichromate by mass percentage.

[0016] In this embodiment, because the vein components of low-grade fluorite ore containing magnesium carbonate are complex, a complexing modifier needs to be added to further regulate the floatability difference between fluorite and (iron) dolomite, calcite and other carbonate vein minerals, and other vein minerals in the flotation reagent system, thereby enhancing the collecting effect of the target mineral. The addition of calcium lignosulfonate not only increases the hydrophilicity of the surface of calcite and other vein minerals, but also reduces the viscosity of the flotation slurry, increases the surface tension of the flotation froth and speeds up the drainage of the interlayer fluid between the froth and the froth, thereby reducing the non-selective entrainment phenomenon in the froth flotation process. The inward polar group of hydroxyethyl cellulose can have a strong affinity with the surface of the vein minerals and compete with the saponified oleic acid for adsorption. In addition, the outward polar group can form a hydrophilic film on the surface of the vein minerals, thereby strengthening the hydrophilicity of the mineral surface and enhancing the inhibitory effect. Because aluminum sulfate can weaken the collecting ability of fatty acid collectors, the recovery rate of fluorite will be negatively affected. Potassium dichromate (K2Cr2O7) can activate fluorite, and the two components complement each other to effectively float fluorite and reduce the recovery effect of the target mineral due to the inhibition of vein minerals.

[0017] In some embodiments, in step S1, the grading and pre-throwing waste treatment comprises the following steps:

[0018] The fluorite ore is crushed and then screened to obtain oversize minerals and undersize minerals;

[0019] The oversize minerals are pre-throwing waste by using a heavy medium cyclone to obtain pre-throwing waste concentrate and tailings I;

[0020] The undersize minerals and the pre-throwing waste concentrate are combined to obtain the pre-enriched minerals.

[0021] In this embodiment, the ore is pre-enriched by first screening and then throwing waste of the oversize minerals by using a heavy medium cyclone, which fully plays the complementary advantages of equipment and process, improves the grade of the ore entering the flotation, effectively reduces the loss of fine fluorite, and improves the recovery rate of fluorite.

[0022] In some embodiments, the screening device used in the screening process is a vibrating screen with a pore size of 0.2-2 mm.

[0023] In this embodiment, the vibrating screen with a specific pore size is used to classify the ore, which can screen out undersize minerals with appropriate particle size and facilitate the subsequent throwing waste of the oversize minerals by using a heavy medium cyclone.

[0024] In some embodiments, after the grinding process in step S2, the proportion of particles with a size of-0.074 mm in the ore sample is 60%-90%, and the concentration of the first slurry is 30%-35%.

[0025] In this embodiment, the preferred grinding method is wet grinding, which grinds the ore sample to a specific fineness and adds water to prepare a first slurry with a specific concentration, which is conducive to the efficient performance of the subsequent flotation process.

[0026] In some embodiments, in step S3, the flotation operation includes 1 roughing operation, 6-9 cleaning operations, and 1-3 scavenging operations; in the cleaning operation, the middlings obtained from the first cleaning and the second cleaning are combined and concentrated to a second slurry with a concentration of 30%-35%, and then the second slurry is subjected to middling re-cleaning operation to obtain middling re-cleaning concentrate which is returned to the roughing operation.

[0027] In this embodiment, when the first slurry formed by the pre-enriched minerals is subjected to flotation, the middlings are concentrated and re-cleaned and then returned to the roughing operation, which can further improve the recovery rate and grade of fluorite to obtain fluorite concentrate with a grade that is easier to sell.

[0028] In some embodiments, the medicament added in the roughing operation includes 500-1500 g / t of sodium carbonate, 800-2000 g / t of acidified water glass, 200-600 g / t of the complex depressant, 100-600 g / t of the complex regulator, and 100-600 g / t of saponified oleic acid.

[0029] In some embodiments, the medicament added in the first 4 cleaning operations includes 100-1000 g / t of acidified water glass, 10-400 g / t of the complex depressant, and 10-200 g / t of the complex regulator; the medicament added in the 5th-9th cleaning operations includes 0-300 g / t of acidified water glass and 0-80 g / t of the complex depressant.

[0030] In some embodiments, the medicament added in the scavenging operation includes 100-400 g / t of acidified water glass, 20-200 g / t of the complex depressant, 10-200 g / t of the complex regulator, and 10-150 g / t of saponified oleic acid.

[0031] In the above embodiments, by adjusting the dosage of the medicament, the medicament can be used in a small amount to achieve a good effect, and the fluorite in the low-grade fluorite ore containing magnesium carbonate can be efficiently floated.

[0032] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the specific embodiments of the present application can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings used in the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0034] Figure 1 The flowchart of the beneficiation method for the low-grade fluorite ore containing magnesium carbonate provided in Embodiment 1 of the present application is shown. DETAILED DESCRIPTION

[0035] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application; the use of the terms "including," "comprising," "having" and "with" in the specification and claims, along with their conjugates, are used to describe various embodiments of the application and are not intended to exclude or require the presence of other features, numbers, steps, operations, components, materials, or combinations thereof.

[0037] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0038] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative embodiments to each other. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0039] Since the conventional beneficiation method of low-grade fluorite ore containing magnesium carbonate type usually adopts the "desliming-flotation-acid leaching (washing)" process, not only the recovery rate is low, but also the fluorite grade needs to be improved by acid leaching treatment, resulting in a sharp increase in the operation and management cost of the beneficiation plant. In order to solve the above problems, the present application provides a beneficiation method for low-grade fluorite ore containing magnesium carbonate type, comprising the following steps:

[0040] S1. The fluorite ore is classified and pre-processed to remove waste, and a pre-enriched mineral is obtained;

[0041] S2. The pre-enriched mineral is ground and treated, and water is added to prepare a first slurry;

[0042] S3. The first slurry is subjected to flotation operation by using a flotation reagent; the flotation reagent comprises a complex inhibitor and a complex modifier; the complex inhibitor comprises aluminum sulfate, sodium hexametaphosphate, tannic acid, citric acid and sodium alginate; the complex modifier comprises calcium lignosulfonate, hydroxyethyl cellulose and potassium dichromate.

[0043] In the technical scheme of the embodiment of the present application, the ore grade entering the flotation is improved, the grinding amount is reduced, and the beneficiation cost is reduced by first performing the classification and pre-throwing waste treatment on the fluorite raw ore; on this basis, the present application optimizes the flotation reagent, adopts the complex reagent mode, combines the inorganic depressant and the organic modifier, can target inhibit the dolomite and calcite in the magnesium carbonate type low-grade fluorite ore, fully plays the complex synergistic effect between the reagents, reduces the heterogeneous condensation between the fluorite and the carbonate particles, strengthens the dispersion degree of the ore slurry, reduces the adsorption amount of the collector on the surface of the fine-grained carbonate mineral, and improves the inhibition effect on the silicate mineral while inhibiting the carbonate mineral, so that the floating rate of the fluorite is accelerated, and the selectivity of the fluorite collector is improved. And the above-mentioned complex reagent has the advantages of non-toxic, environmental protection, easy to obtain raw materials, and less reagent consumption, and has extremely high industrial application prospect.

[0044] Further, in some embodiments, the complex depressant includes 20% to 50% aluminum sulfate, 10% to 30% sodium hexametaphosphate, 5% to 20% tannic acid, 5% to 20% citric acid, and 5% to 20% sodium alginate by mass percentage, and more preferably, the mass ratio of aluminum sulfate, sodium hexametaphosphate, tannic acid, citric acid, and sodium alginate in the complex depressant is 4:2:2:1:1. At the same time, the complex modifier includes 20% to 60% calcium lignosulfonate, 5% to 40% hydroxyethyl cellulose, and 5% to 40% potassium dichromate by mass percentage, and more preferably, the mass ratio of calcium lignosulfonate, hydroxyethyl cellulose, and potassium dichromate in the complex modifier is 5:3:2.

[0045] In the technical scheme of the embodiment of the present application, by controlling the ratio of each raw material in the complex depressant and the complex modifier, the synergistic effect between each raw material can be fully played, the inhibition effect on the carbonate mineral and the silicate can be improved, and the selectivity of the fluorite collector can be improved, so that the recovery rate and the grade of the fluorite are improved.

[0046] Further, in some embodiments, in step S1, the classification and pre-throwing waste treatment includes the following steps:

[0047] The fluorite ore is crushed and then screened to obtain the oversize mineral and the undersize mineral;

[0048] The heavy medium cyclone is used to pre-throw the waste of the oversize mineral to obtain the pre-throwing waste concentrate and the tailings I;

[0049] The undersize mineral and the pre-throwing waste concentrate are combined to obtain the pre-enriched mineral.

[0050] In the technical scheme of the embodiment of the present application, the pre-concentration of the raw ore is performed by first screening and then discarding the oversize minerals by using the heavy medium cyclone, so that the advantages of the equipment and the process are complemented, the grade of the raw ore entering the flotation is improved, the loss of the fine particle fluorite is effectively reduced, and the recovery of the fluorite is improved.

[0051] Further, in some embodiments, the screening device used in the screening process is a vibrating screen with a pore size of 0.2-2 mm, so as to screen the undersize minerals with a suitable particle size, and facilitate the subsequent discarding of the oversize minerals by using the heavy medium cyclone.

[0052] Further, in some embodiments, after the grinding process in step S2, the proportion of the particles with a size of-0.074 mm in the ore sample is 60-90%, and the concentration of the first ore slurry is 30-35%.

[0053] In the technical scheme of the embodiment of the present application, the grinding method is preferably wet grinding, the ore sample is ground to a specific fineness, and water is added to prepare a first ore slurry with a specific concentration, which is beneficial to the efficient subsequent flotation process.

[0054] Further, in some embodiments, in step S3, the flotation operation includes 1 roughing operation, 6-9 cleaning operations, and 1-3 scavenging operations, and specifically includes the following steps:

[0055] S31. Adding a roughing reagent to the first ore slurry to obtain a roughing concentrate and a roughing tailing; wherein the roughing reagent includes: sodium carbonate with an addition amount of 500-1500 g / t, acidified water glass with an addition amount of 800-2000 g / t, the complex inhibitor with an addition amount of 200-600 g / t, the complex modifier with an addition amount of 100-600 g / t, and saponified oleic acid with an addition amount of 100-600 g / t.

[0056] In the above reagents, the acidified water glass is mixed by water glass and sulfuric acid in a mass ratio of 2:1, and the amount is calculated based on the water glass; the saponified oleic acid is formed by mixing vegetable oleic acid and sodium carbonate in a mass percentage of 25-60%:40-75% and then saponifying, and when preparing the saponified oleic acid, first, the sodium carbonate is prepared into a sodium carbonate solution with a mass fraction of 20-40%, and then the solution is combined with the oleic acid in a water bath at 90-100℃ to perform the saponification reaction. The preferred composition and preparation method of the acidified water glass and the saponification in the following are the same, and will not be repeated here.

[0057] S32. The roughing concentrate is subjected to 6-9 cleaning operations, and the flotation concentration in the cleaning operation stage is 10%-28%; wherein the middlings obtained in the first cleaning and the second cleaning are combined and concentrated into a second slurry with a concentration of 30%-35%, and then the middlings are subjected to re-cleaning operation, and the re-cleaning operation uses a reagent which is saponified oleic acid with an addition amount of 10-100 g / t, to obtain re-cleaning concentrate and re-cleaning tailings, the re-cleaning concentrate is returned to the roughing operation, and the re-cleaning tailings are used as the final tailings II; the middlings generated in the subsequent cleaning operations are returned to the previous operation step by step, and the concentrate obtained in the last cleaning operation is used as the final fluorite concentrate product.

[0058] In the above cleaning operation, the reagent used in the first cleaning includes acidified water glass with an addition amount of 100-1000 g / t, a complex inhibitor with an addition amount of 50-400 g / t, and a complex regulator with an addition amount of 50-200 g / t; the reagent used in the second cleaning includes acidified water glass with an addition amount of 100-800 g / t, a complex inhibitor with an addition amount of 50-200 g / t, and a complex regulator with an addition amount of 20-100 g / t; the reagent used in the third cleaning includes acidified water glass with an addition amount of 100-600 g / t, a complex inhibitor with an addition amount of 20-100 g / t, and a complex regulator with an addition amount of 10-80 g / t; the reagent used in the fourth cleaning includes acidified water glass with an addition amount of 100-400 g / t, a complex inhibitor with an addition amount of 10-100 g / t, and a complex regulator with an addition amount of 10-60 g / t; the reagent used in the fifth cleaning includes acidified water glass with an addition amount of 100-300 g / t and a complex inhibitor with an addition amount of 5-80 g / t; the reagent used in the sixth cleaning includes acidified water glass with an addition amount of 100-400 g / t and a complex inhibitor with an addition amount of 5-60 g / t; the reagent used in the seventh cleaning includes acidified water glass with an addition amount of 100-300 g / t and a complex inhibitor with an addition amount of 5-40 g / t; the reagent used in the eighth cleaning includes acidified water glass with an addition amount of 100-300 g / t and a complex inhibitor with an addition amount of 0-20 g / t; the reagent used in the ninth cleaning includes acidified water glass with an addition amount of 0-300 g / t and a complex inhibitor with an addition amount of 0-60 g / t.

[0059] S32. The roughing concentrate is subjected to 6-9 cleaning operations, and the flotation concentration in the cleaning operation stage is 10%-28%; wherein the middlings obtained in the first cleaning and the second cleaning are combined and concentrated into a second slurry with a concentration of 30%-35%, and then the middlings are subjected to re-cleaning operation, and the re-cleaning operation uses a reagent which is saponified oleic acid with an addition amount of 10-100 g / t, to obtain re-cleaning concentrate and re-cleaning tailings, the re-cleaning concentrate is returned to the roughing operation, and the re-cleaning tailings are used as the final tailings II; the middlings generated in the subsequent cleaning operations are returned to the previous operation step by step, and the concentrate obtained in the last cleaning operation is used as the final fluorite concentrate product.

[0060] The reagent used in the cleaning operation includes acidified water glass with an addition amount of 100-400 g / t, the complex inhibitor with an addition amount of 20-200 g / t, the complex regulator with an addition amount of 10-200 g / t, and saponified oleic acid with an addition amount of 10-150 g / t.

[0061] By the above manner, the beneficiation method for the low-grade fluorite ore containing magnesium carbonate type provided by the embodiment of the application can utilize the synergistic effect between the specific beneficiation process and the improved reagent system, cancel the acid leaching operation, and improve the fluorite recovery rate and grade with a simpler process and lower reagent cost. The overall process is stable and reliable, the beneficiation reagent cost is reduced by more than 40% compared with the existing process, the economic benefit is higher, the use of hydrochloric acid is omitted, it is more environmentally friendly, and has a very high industrial application prospect.

[0062] Some specific examples are listed below. It should be noted that the examples described below are exemplary and are used to explain the application only, and cannot be understood as a limitation of the application. If the specific technology or condition is not specified in the examples, the technology or condition described in the literature in the art or according to the product manual is used. If the reagent or instrument is not specified by the manufacturer, it is a conventional product that can be obtained by purchase.

[0063] Example 1

[0064] The embodiment provides a beneficiation method for a low-grade fluorite ore containing magnesium carbonate type. Taking a low-grade fluorite ore containing magnesium carbonate type in Inner Mongolia as a test object, the CaF2 content in the raw ore is 20.70%, the CaCO3 content is 19.07%, the MgO content is 3.94%, and a small amount of altered feldspar, quartz and other gangue minerals are also contained. The carbonate gangue mainly exists in the form of dolomite, calcite and ankerite minerals.

[0065] The flowchart of the beneficiation method for the low-grade fluorite ore containing magnesium carbonate type provided by the embodiment is shown in Figure 1 The method specifically comprises the following steps:

[0066] S1. After the raw ore is crushed to-2mm, the sieve with a mesh size of 0.5mm is used for classification treatment, and the oversize mineral and undersize mineral are obtained. The oversize mineral is sent to the heavy medium cyclone for pre-throwing waste treatment, and the pre-throwing waste concentrate and tailings I are obtained. The undersize mineral and the pre-throwing waste concentrate are combined to obtain the pre-enriched mineral.

[0067] S2. The pre-enriched mineral is subjected to wet grinding treatment, the grinding fineness is that the-0.074mm mineral powder particles account for 70.18% of the total grinding powder, and the first slurry with a mass concentration of 33% is prepared by adding water.

[0068] S3. The first slurry is subjected to flotation operation by using a flotation reagent; the flotation operation includes 1 roughing operation, 9 cleaning operations and 1 scavenging operation, and the specific steps are as follows:

[0069] S31. Adding a roughing reagent to the first ore pulp to obtain a roughing concentrate and a roughing tailings; wherein the roughing reagent comprises: sodium carbonate with an addition amount of 800 g / t, acidified water glass with an addition amount of 1500 g / t, a complex inhibitor (i.e. CD-WN in Figure 1 ) with an addition amount of 400 g / t, a complex regulator (i.e. CN-WH in Figure 1 ) with an addition amount of 200 g / t, and saponified oleic acid with an addition amount of 500 g / t.

[0070] S32. Carrying out 9 times of cleaning operations on the roughing concentrate; wherein the middlings obtained from the 1st cleaning and the 2nd cleaning are combined and concentrated into a second ore pulp with a concentration of 31%, then 50 g / t of saponified oleic acid is added to the second ore pulp to carry out a middling re-cleaning operation, to obtain a middling re-cleaning concentrate and a middling re-cleaning tailings, the middling re-cleaning concentrate returns to the roughing operation, and the middling re-cleaning tailings are taken as the final tailings II; the middlings generated in the subsequent cleaning operations are returned to the previous operation step by step, and the concentrate obtained from the last cleaning operation is taken as the final fluorite concentrate product.

[0071] In the above cleaning operations, the reagents used in the 1st cleaning include acidified water glass with an addition amount of 800 g / t, a complex inhibitor with an addition amount of 200 g / t, and a complex regulator with an addition amount of 100 g / t; the reagents used in the 2nd cleaning include acidified water glass with an addition amount of 500 g / t, a complex inhibitor with an addition amount of 100 g / t, and a complex regulator with an addition amount of 50 g / t; the reagents used in the 3rd cleaning include acidified water glass with an addition amount of 400 g / t, a complex inhibitor with an addition amount of 100 g / t, and a complex regulator with an addition amount of 20 g / t; the reagents used in the 4th cleaning include acidified water glass with an addition amount of 300 g / t, a complex inhibitor with an addition amount of 20 g / t, and a complex regulator with an addition amount of 10 g / t; the reagents used in the 5th cleaning include acidified water glass with an addition amount of 200 g / t, and a complex inhibitor with an addition amount of 20 g / t; the reagents used in the 6th cleaning include acidified water glass with an addition amount of 200 g / t, and a complex inhibitor with an addition amount of 15 g / t; the reagents used in the 7th cleaning include acidified water glass with an addition amount of 100 g / t, and a complex inhibitor with an addition amount of 10 g / t; the reagents used in the 8th cleaning include acidified water glass with an addition amount of 100 g / t, and a complex inhibitor with an addition amount of 5 g / t; and the 9th cleaning is a blank cleaning, i.e. no reagent is added.

[0072] S32. One scavenging operation is performed on the roughing tailings to obtain final tailings III, and the scavenging concentrate obtained in the scavenging operation is returned to the roughing operation. The reagents used in the scavenging operation include acidified water glass with an addition amount of 200 g / t, the complex inhibitor with an addition amount of 100 g / t, the complex modifier with an addition amount of 50 g / t, and saponified oleic acid with an addition amount of 100 g / t.

[0073] In the above reagents, the complex inhibitor is mixed by aluminum sulfate, sodium hexametaphosphate, tannic acid, citric acid and sodium alginate according to the mass ratio of 4:2:2:1:1, and the complex modifier is mixed by calcium lignosulfonate, hydroxyethyl cellulose and potassium dichromate according to the mass ratio of 5:3:2.

[0074] The test results obtained after the beneficiation according to the beneficiation method provided in the above embodiment are shown in Table 1.

[0075] Table 1: Results of the closed-circuit test in the whole process in Example 1 (%)

[0076]

[0077] As can be seen from Table 1, the beneficiation method provided in the above embodiment is used to recover a certain low-grade fluorite ore containing magnesium carbonate in Inner Mongolia, the recovery rate of CaF2 is 78.77%, and the final CaF2 grade is 95.46%, which contains CaCO3 1.38% and MgO 0.13%, belonging to high-quality fluorite concentrate, indicating that the method provided in the above embodiment has very important significance for the development and utilization of low-grade fluorite ore containing magnesium carbonate.

[0078] Example 2

[0079] The beneficiation method for low-grade fluorite ore containing magnesium carbonate provided in the above embodiment takes a certain low-grade fluorite ore containing magnesium carbonate in Xinjiang as the test object, the CaF2 content in the raw ore is 22.53%, the CaCO3 content is 19.15%, the MgO content is 4.31%, the gangue is mainly quartz, and the carbonate gangue mainly exists in the form of dolomite and calcite minerals. Compared with Example 1, the main difference of the beneficiation method provided in the above embodiment is that the proportion of -0.074 mm mineral powder particles in the total grinding ore powder in step S2, the dosage of part of the reagents in step S3 and the concentration of the second slurry in the re-beneficiation of middlings are adjusted.

[0080] Specifically, in this embodiment, the -0.074 mm ore powder particles in step S2 account for 78.95% of the total amount of the ground ore powder; the concentration of the second slurry is 32%; the addition amount of sodium carbonate in roughing is 1000 g / t, the addition amount of the compounded inhibitor is 450 g / t; the addition amount of the compounded inhibitor in the first cleaning is 250 g / t, the addition amount of the compounded inhibitor in the second cleaning is 100 g / t, the addition amount of the compounded inhibitor in the third cleaning is 80 g / t, the addition amount of the compounded inhibitor in the fourth cleaning is 40 g / t, the addition amount of the compounded inhibitor in the fifth cleaning is 30 g / t, and the addition amount of the compounded inhibitor in the sixth cleaning is 20 g / t. The rest is basically the same as that in Embodiment 1, which is not described here again.

[0081] The test results obtained after the beneficiation according to the beneficiation method provided in this embodiment are shown in Table 2.

[0082] Table 2: Results of the whole-process closed-circuit test in Embodiment 2 (%)

[0083]

[0084] As can be seen from Table 2, the beneficiation method provided in this embodiment is used to recover a certain magnesium carbonate type low-grade fluorite ore in Xinjiang, the recovery rate of CaF2 is 79.02%, and the final CaF2 grade obtained is 95.52%, which contains 1.20% of CaCO3 and 0.20% of MgO, belonging to high-quality fluorite concentrate.

[0085] Embodiment 3

[0086] This embodiment provides a beneficiation method for a magnesium carbonate type low-grade fluorite ore. A certain magnesium carbonate type low-grade fluorite ore in Fujian is taken as the test object, the CaF2 content in the raw ore is 18.23%, the CaCO3 content is 17.96%, the MgO content is 4.34%, the gangue is mainly feldspar and quartz, and the carbonate gangue mainly exists in the form of calcite and iron dolomite minerals. The beneficiation method provided in this embodiment is mainly different from that in Embodiment 1 in that the proportion of -0.074 mm ore powder particles in the total amount of the ground ore powder in step S2, the concentration of the first slurry, the dosage of part of the reagents in step S3, and the concentration of the second slurry in the re-beneficiation of the middlings are adjusted.

[0087] Specifically, in the embodiment, the -0.074 mm ore powder particles in step S2 account for 68% of the total amount of the ore powder entering the mill, the concentration of the first slurry is 30%, and the concentration of the second slurry is 35%; the addition amount of sodium carbonate in roughing is 1000 g / t, the addition amount of the compounded inhibitor is 500 g / t, and the addition amount of saponified oleic acid is 400 g / t; the addition amount of the compounded inhibitor in the first cleaning is 300 g / t, the addition amount of the compounded inhibitor in the second cleaning is 150 g / t, the addition amount of the compounded modifier is 100 g / t, the addition amount of the compounded inhibitor in the third cleaning is 70 g / t, the addition amount of the compounded inhibitor in the fourth cleaning is 35 g / t, and the addition amount of saponified oleic acid in scavenging is 80 g / t. The rest is basically the same as that in Embodiment 1 and is not described herein again.

[0088] The test results obtained after the beneficiation according to the beneficiation method provided in the embodiment are shown in Table 3.

[0089] Table 3: Results of the whole-process closed-circuit test in Embodiment 3 (%)

[0090]

[0091]

[0092] As can be seen from Table 3, the beneficiation method provided in the embodiment is used to recover a certain magnesium carbonate type low-grade fluorite ore in Fujian, the recovery rate of CaF2 is 80.19%, and the final CaF2 grade obtained is 95.11%, containing CaCO3 1.36%, and MgO 0.30%, which belongs to high-quality fluorite concentrate.

[0093] According to the test results of Embodiments 1-3, it can be seen that the beneficiation method provided in the application can be applied to different types of magnesium carbonate type low-grade fluorite ore, and the corresponding beneficiation parameters can be appropriately adjusted within a certain range. When the beneficiation is performed according to the method provided in the application, the recovery rate of CaF2 can be more than 78%, and the grade of CaF2 can be more than 95%, achieving high-grade high-quality fluorite concentrate with high recovery rate, which has very practical value for efficient recovery of magnesium carbonate type low-grade fluorite ore.

[0094] Embodiments 4-5 and Comparative Examples 1-3

[0095] Embodiments 4-5 and Comparative Examples 1-3 each provide a beneficiation method for a magnesium carbonate type low-grade fluorite ore. Compared with Embodiment 1, the difference lies in the change of the composition of the compounded inhibitor. The proportions of the raw materials in the compounded inhibitor in each embodiment and comparative example are shown in Table 4. The total amount of the compounded inhibitor, the raw ore used, and the rest of the steps are consistent with Embodiment 1, and are not described herein again.

[0096] Table 4 Composition of the compounded inhibitors in Examples 4-5 and Comparative Examples 1-3

[0097]

[0098] After the beneficiation is respectively performed according to the beneficiation methods provided in Examples 4-5 and Comparative Examples 1-3, the yield, grade and recovery rate of the fluorite flotation concentrate obtained are shown in Table 5.

[0099] Table 5 Results of the whole-closed-circuit test in Examples 4-5 and Comparative Examples 1-3 (%)

[0100]

[0101] As can be seen from Table 5, within the recommended range of the proportion of the reagents, the CaF2 grade in the fluorite flotation concentrate of Examples 4 and 5 both reaches 95% grade, and the grades of CaCO3 and MgO are within the range of qualified products. Adjusting the proportion of aluminum sulfate and sodium hexametaphosphate in the inhibitor has a greater impact on the yield of the concentrate product, and further affects the recovery rate of the concentrate. After the proportion of the compounded inhibitor deviates from the recommended range, it has a greater impact on the grades of CaF2, CaCO3 and MgO in the fluorite concentrate, and the synergistic effect between the reagents cannot be fully played out. The flotation concentrate of Comparative Examples 1-3 does not reach the standard of 95% grade fluorite concentrate powder, and can only be sold as 93% grade fluorite concentrate powder, greatly reducing the value of the beneficiation product. Therefore, according to the different properties of the ore, the proportion of various inhibitors in the compounded inhibitor needs to be reasonably allocated, so that the synergistic effect between the reagents can be fully played out, and the effective utilization value of the resources is improved.

[0102] Examples 6-7 and Comparative Examples 4-7

[0103] Examples 6-7 and Comparative Examples 4-7 respectively provide a beneficiation method for a magnesium carbonate-containing low-grade fluorite ore. Compared with Example 1, the difference lies in the composition of the compounded adjusting agent. The proportions of the raw materials in the compounded adjusting agent in each example and comparative example are shown in Table 6. The total amount of the compounded adjusting agent, the raw ore used and the remaining steps are consistent with Example 1, and will not be described here.

[0104] Table 6 Composition of the compounded adjusting agent in Examples 6-7 and Comparative Examples 4-7

[0105]

[0106]

[0107] After the beneficiation is respectively performed according to the beneficiation methods provided in Examples 6-7 and Comparative Examples 4-7, the yield, grade and recovery rate of the fluorite flotation concentrate obtained are shown in Table 7.

[0108] Table 7: Results of closed-circuit tests in Examples 6-7 and Comparative Examples 4-7 (%)

[0109]

[0110] As can be seen from Table 7, when the proportion of calcium lignosulfonate in the complex modifier is reduced, the yield of fluorite concentrate and the CaF2 recovery rate are slightly increased, but the grade of CaCO3 and MgO is increased, and the hydrophobicity of the modifier on the surface of carbonate is weakened; when the proportion of hydroxyethyl cellulose is reduced, the competitive adsorption of hydroxyethyl cellulose and oleic acid on the surface of carbonate minerals is weakened, which causes the grade of fluorite concentrate to decrease to a certain extent, but the grade of CaCO3 and MgO in the concentrate is less affected. Potassium dichromate is added to partially inhibit the effect of aluminum sulfate and other inhibitors on fluorite minerals during fluorite flotation, so if the proportion of potassium dichromate is cancelled, it will have a more obvious negative impact on the CaF2 recovery rate of fluorite concentrate.

[0111] In summary, the present application provides a beneficiation method for low-grade fluorite ore containing magnesium carbonate, which belongs to the technical field of fluorite beneficiation. The present application obtains a pre-enriched mineral by grading and pre-throwing waste treatment on the fluorite raw ore; the pre-enriched mineral is subjected to grinding treatment, and after adding water, a first ore slurry is prepared; the first ore slurry is subjected to flotation operation by using flotation reagents; the flotation reagents include a complex depressant and a complex modifier, the complex depressant includes aluminum sulfate, sodium hexametaphosphate, tannic acid, citric acid and sodium alginate, and the complex modifier includes calcium lignosulfonate, hydroxyethyl cellulose and potassium dichromate. Through the above-mentioned manner, the beneficiation method for low-grade fluorite ore containing magnesium carbonate provided by the present application can utilize the synergistic effect between the specific beneficiation process and the improved reagent system, cancel the acid leaching operation, and improve the fluorite recovery rate and grade with a simpler process and lower reagent cost, which has a very high industrial application prospect.

[0112] It should be noted that the present application is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and embodiments having the same technical idea and playing the same role and effect within the scope of the technical solution of the present application are all included in the technical scope of the present application. In addition, within the scope of the main idea of the present application, various modifications of the embodiments that can be thought of by those skilled in the art, and other ways constructed by combining part of the constituent elements of the embodiments are also included in the scope of the present application.

Claims

1. A beneficiation method for a low-grade fluorite ore containing magnesium carbonate, characterized by, The method comprises the following steps: S1. grading and pre-throwing waste treatment are performed on fluorite raw ore to obtain pre-enriched minerals; S2. grinding treatment is performed on the pre-enriched minerals, and water is added to prepare a first ore slurry; S3. flotation reagents are used to perform flotation operation on the first ore slurry; the flotation reagents comprise a compound inhibitor and a compound regulator; the compound inhibitor comprises, in terms of mass percentage, 20-50% of aluminum sulfate, 10-30% of sodium hexametaphosphate, 5-20% of tannic acid, 5-20% of citric acid and 5-20% of sodium alginate; the compound regulator comprises, in terms of mass percentage, 20-60% of calcium lignosulfonate, 5-40% of hydroxyethyl cellulose and 5-40% of potassium dichromate.

2. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 1, characterized in that, In step S1, the grading and pre-throwing waste treatment comprises the following steps: After the fluorite ore is crushed, screening treatment is performed to obtain oversize minerals and undersize minerals; A heavy medium cyclone is used to pre-throw waste on the oversize minerals to obtain pre-throwing waste concentrate and tailings I; The undersize minerals and the pre-throwing waste concentrate are combined to obtain the pre-enriched minerals.

3. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 2, characterized in that, The screening treatment is performed by using a vibrating screen with a pore size of 0.2-2 mm.

4. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 1, characterized in that, In step S2, after the grinding treatment, the proportion of particles with a size of-0.074 mm in the ore sample is 60-90%; the concentration of the first ore slurry is 30-35%.

5. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 1, characterized in that, In step S3, the flotation operation comprises one roughing operation, 6-9 cleaning operations and 1-3 scavenging operations; in the cleaning operation, the middlings obtained in the first cleaning and the second cleaning are combined and concentrated into a second ore slurry with a concentration of 30-35%, and then the middlings re-selection operation is performed on the second ore slurry to obtain middlings re-selection concentrate which is returned to the roughing operation.

6. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 5, characterized in that, The reagents added in the roughing operation include 500-1500 g / t of sodium carbonate, 800-2000 g / t of acidified water glass, 200-600 g / t of the compound inhibitor, 100-600 g / t of the compound regulator and 100-600 g / t of saponified oleic acid.

7. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 5, characterized in that, In the cleaning operation, the reagents added in the first four cleaning operations include 100-1000 g / t of acidified water glass, 10-400 g / t of the compound inhibitor and 10-200 g / t of the compound regulator; the reagents added in the fifth to ninth cleaning operations include 0-300 g / t of acidified water glass and 0-80 g / t of the compound inhibitor.

8. The beneficiation method for low-grade fluorite ore containing magnesium carbonate type according to claim 5, characterized in that, The reagents added in the scavenging operation include 100-400 g / t of acidified water glass, 20-200 g / t of the compound inhibitor, 10-200 g / t of the compound regulator and 10-150 g / t of saponified oleic acid.

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