Efficient beneficiation method for niobium ore

Abstract

An efficient beneficiation method for niobium ore, relating to the technical field of beneficiation. The method comprises: crushing raw niobium ore and performing low-intensity magnetic separation to remove highly magnetic iron ore, performing desliming treatment on low-intensity magnetic tailings, and then performing high-intensity magnetic separation to obtain high-intensity magnetic concentrate and high-intensity magnetic tailings; performing desiliconization reverse flotation on the high-intensity magnetic concentrate to obtain desiliconized tailings; performing dewatering, reagent removal, and desliming on the desiliconized tailings, and then performing niobium flotation I to obtain niobium concentrate I; performing niobium flotation II on the high-intensity magnetic tailings to obtain niobium concentrate II; and performing dewatering and reagent removal on the niobium concentrate II, and then performing upgrading flotation III to obtain niobium concentrate III. On the basis of the mineralogical characteristics of niobium ore, magnetic separation is first performed for classification, and different flotation methods are respectively applied to magnetic niobium‑containing minerals and non‑magnetic niobium‑containing minerals for enrichment of niobium minerals, which not only improves the overall recovery efficiency of niobium ore, but also increases the niobium concentrate grade and reduces reagent consumption.

Description

A Highly Efficient Beneficiation Method for Niobium Ore Technical Field

[0001] This invention relates to a method for beneficiating niobium ore, and more particularly to a method for the efficient flotation development and utilization of niobium ore, belonging to the field of mineral processing technology. Background Technology

[0002] Niobium is a lustrous, grayish-white transition metal with corrosion resistance and high ductility. It exhibits superconductivity at low temperatures and is the most effective microalloying element in metallic materials. It is a key element in aerospace, superconducting materials, medical materials, and metallurgical industries. Technical issues

[0003] Primary niobium deposits are relatively rare in nature. Currently, there are two types of niobium deposits: granite-related deposits (including rare metal granite-type and pegmatite-type deposits, with niobium-bearing minerals such as columbite, columbite-rutile, xenotime, and ferruginous minerals) and deposits related to alkaline and basic-ultrabasic complexes (with niobium-bearing minerals such as pyrochlore, cerium-niobium perovskite, and calcite). Global niobium resources are mainly concentrated in Brazil and Canada. China has relatively abundant niobium reserves, but most are low-grade ores with many associated minerals, which is insufficient to meet domestic demand. Therefore, there is an urgent need to develop technologies for the efficient enrichment of niobium resources from low-grade ores.

[0004] Flotation is one of the most important methods for the industrial recovery of various niobium minerals, with collectors playing a crucial role in collection and enrichment. Collectors for niobium mineral flotation include fatty acids, arsenoic acids, hydroxamic acids, phosphonic acids, and amines. Although bisphosphonic acids and arsenoic acids exhibit good selectivity for niobium-bearing minerals such as niobite and pyrochlore, their preparation and use cause serious environmental pollution. While fatty acids have a strong collecting ability for niobium minerals, they typically also collect gangue minerals such as carbonates and silicates, resulting in poor selectivity. Hydroxamic acids have a high selective chelating ability for metal ions, such as iron ions, inevitably leading to selective enrichment of iron-bearing gangue minerals during niobium flotation. This significantly impacts the flotation efficiency and product quality of niobium. Amine collectors can effectively collect niobium minerals, but their disadvantage is that they also exhibit strong collecting properties for slime and siliceous minerals, and the foam viscosity is high, resulting in a high niobium runoff in the tailings, which greatly reduces the recovery rate and grade of niobium ore. Technical solutions

[0005] To address the technical problems in existing niobium ore beneficiation processes, such as poor selectivity, high reagent consumption, excessive mud and siliceous mineral contamination, low niobium ore recovery rate, and low recovery grade, the present invention aims to provide a highly efficient niobium ore beneficiation method. This method, tailored to the mineral composition characteristics of niobium ore, first uses magnetic separation to separate the minerals and then employs different flotation methods for magnetic and non-magnetic niobium-bearing minerals to enrich the niobium minerals. This not only improves the overall recovery efficiency of niobium ore but also increases the grade of niobium concentrate and reduces reagent consumption.

[0006] To achieve the above-mentioned technical objectives, the present invention provides a highly efficient beneficiation method for niobium ore, the method comprising the following steps:

[0007] 1) After crushing the niobium ore, weak magnetic treatment is performed to remove the strong magnetic iron ore. The weak magnetic tailings are deslimed and then subjected to strong magnetic treatment to obtain strong magnetic concentrate and strong magnetic tailings.

[0008] 2) After pH adjustment, the strong magnetic concentrate is subjected to desilication reverse flotation with flotation reagents including starch inhibitors and ether amine collectors to obtain desilication tailings;

[0009] 3) After dewatering, de-reagenting and desliming the desilication tailings, flotation reagents including fluorosilicic acid inhibitors and amine collectors are added to perform niobium flotation I to obtain niobium concentrate I;

[0010] 4) Add flotation reagents, including silica mineral inhibitors and hydroxamic acid metal complex collectors, to the strongly magnetic tailings for niobium flotation II to obtain niobium concentrate II.

[0011] 5) After dehydration and de-reagent treatment, niobium concentrate II is subjected to flotation III with flotation reagents including fluorosilicic acid inhibitor-activator and amine collector to obtain niobium concentrate III.

[0012] The niobium ore involved in this invention mainly contains calcite [CaCO3], dolomite [CaMg(CO3)2], ferromagnetic dolomite [Ca(Mg,Fe)(CO3)2], potassium feldspar [K2O·Al2O3·6SiO2], and phlogopite [KMg3(Si3AlO2]]. 10 (OH)2], biotite [K(Mg,Fe)3(Al,Fe)Si3O 10 The niobium ore contains minerals such as niobium (Ca(PO4)3(F,OH)), magnetite (Fe3O4), apatite (Ca5(PO4)3(F,OH)), and pyrochlore ((Ca,Na)2(Nb,Ti)2O6F). The Nb2O5 content in the raw niobium ore is generally 0.5-2% by mass, and the total iron content is generally 8-15%.

[0013] This invention is based on the phase composition and distribution characteristics of niobium ore. Niobium ore mainly comprises iron minerals, siliceous minerals (gangue minerals), and niobium minerals. Conventional amine collectors are sensitive to siliceous minerals, while hydroxamic acid collectors are difficult to separate iron and niobium. The key to this invention is to first perform pre-separation using magnetic separation. Weak magnetic separation is used to remove strongly magnetic iron ores such as magnetite, and then strong magnetic separation is used to separate the niobium minerals into magnetic niobium-bearing minerals and non-magnetic niobium-bearing minerals. The main gangue mineral in the magnetic niobium-bearing minerals is iron minerals. The main gangue minerals in this invention, which are non-magnetic niobium-bearing minerals, are siliceous minerals. Based on the mineral composition characteristics of both magnetic and non-magnetic niobium-bearing minerals, reasonable flotation reagent systems are designed. For magnetic niobium-bearing minerals, after further desilication, amine collectors are used to achieve efficient flotation separation between the niobium-bearing minerals and ferrous gangue minerals. For non-magnetic niobium-bearing minerals, hydroxamic acid metal complex collectors are used to achieve efficient separation between the niobium-bearing minerals and siliceous gangue minerals. Further flotation with amine collectors is then used to improve the grade of the niobium ore. In summary, this invention designs a reasonable beneficiation process that can significantly improve the recovery rate of niobium ore and simplify the process flow.

[0014] As a preferred embodiment, the magnetic weakening treatment employs a magnetic field strength of 0.15T to 0.3T. This magnetic weakening treatment can effectively remove strongly magnetic minerals such as magnetite, ilmenite, and hematite, reducing the difficulty of subsequent iron-niobium flotation separation.

[0015] As a preferred embodiment, the strong magnetic treatment employs a magnetic field strength of 1.2T to 1.5T. Through this treatment, weakly magnetic ferrous minerals and associated niobium minerals can be separated from siliceous minerals. The main purpose is to achieve desilication and avoid the influence of siliceous minerals on the recovery of niobium ore using amine collectors.

[0016] As a preferred embodiment, in step 2), the pH is adjusted to 10-11. Under these preferred pH conditions, favorable pH conditions are provided for the flotation of siliceous minerals using ether-amine collectors. The pH is adjusted using conventional alkaline reagents, such as sodium hydroxide or sodium carbonate.

[0017] As a preferred embodiment, the desilication reverse flotation includes a primary roughing flotation process. As a more preferred embodiment, the reagent regime for the roughing flotation is: starch inhibitor 300g / t~800g / t; ether amine collector 100g / t~300g / t. The starch inhibitor is mainly used to suppress ferrous minerals. Specific examples of ether amine collectors include C... 10 ~C 13Etheramine acetate. Starch inhibitors include commercially available soluble starches or modified starches. Soluble starches include rice starch, corn starch, millet starch, potato starch, and sweet potato starch; modified starches include cationic modified starches (commonly quaternary ammonium salt modified starches, such as starch etherified with 3-chloro-2-hydroxypropyltrimethylammonium chloride), anionic modified starches (e.g., oxidized starch, carboxymethyl starch, succinate starch, etc.), with soluble starches being the most preferred. C 10 ~C 13 Etheramine acetates are common commercially available products, with common chemical formulas such as: R–O–(CH2–CH2O)–CH2CH2CH2–NH3 + CH3COO - (where R=C) 10 ~ C 13 (isoalkyl groups).

[0018] As a preferred embodiment, the niobium flotation I employs a roughing and cleaning process. The roughing reagent regimen is as follows: 1500g / t~2500g / t of fluorosilicic acid inhibitor, 100g / t~300g / t of amine collector, and 30g / t~80g / t of defoamer. The primary cleaning reagent regimen is: 1500g / t~2500g / t of fluorosilicic acid inhibitor and 30g / t~80g / t of amine collector. The secondary cleaning reagent regimen is: 1500g / t~2500g / t of fluorosilicic acid inhibitor. The tertiary cleaning reagent regimen is: 1300g / t~1800g / t of fluorosilicic acid inhibitor. The fluorosilicic acid inhibitor serves two purposes: firstly, as a pH adjuster to regulate the suitable pH range for flotation; and secondly, as an inhibitor, primarily used to suppress ferrous minerals. After strong magnetic separation of siliceous minerals, the influence of siliceous minerals on the separation of niobium minerals by the amine collector is significantly reduced. Defoamers such as P86.

[0019] As a preferred embodiment, the amine collector comprises an aliphatic diamine with 10-20 carbon atoms. The aliphatic diamine is a conventional commercially available product, specifically such as 1,10-decanediamine, 1,12-dodecanediamine, 1,14-tetradecanediamine, 1,16-hexadecanediamine, 1,18-octadecanediamine, and tallow diamine (mainly containing C...). 16 / C 18 (diamine mixtures), etc.

[0020] As a preferred embodiment, the niobium flotation II adopts a roughing and cleaning flotation process; wherein, the reagent regime for roughing is: 50g / t~150g / t of silica mineral depressant, 300g / t~800g / t of hydroxamic acid metal complex collector, and 30g / t~80g / t of frother; the reagent regime for primary cleaning is: 30g / t~80g / t of silica mineral depressant; the reagent regime for secondary cleaning is: 15g / t~35g / t of silica mineral depressant; and the reagent regime for tertiary cleaning is: 5g / t~15g / t of silica mineral depressant; the frother is further preferably BK205. Since strong magnetic tailings also contain non-magnetic iron ore, the use of hydroxamic acid metal complex collectors in combination with silica mineral inhibitors can enhance the flotation separation of silica minerals and niobium minerals. Furthermore, a small amount of non-magnetic iron minerals and other minerals enter the concentrate along with the niobium minerals, and the subsequent use of amine collectors can easily achieve further upgrading of the niobium minerals.

[0021] As a preferred embodiment, the silicon-based mineral inhibitor includes at least one of sodium hexametaphosphate, carboxymethyl cellulose, tannin, water glass, chlorinated water glass, sodium fluorosilicate, fluorosilicic acid, and starch. Chlorinated water glass is commonly ferric chlorinated water glass or aluminum chlorinated water glass, specifically aluminum sulfate chlorinated water glass.

[0022] As a preferred embodiment, the hydroxamic acid organometallic complex collector comprises at least one of benzyl hydroxamic acid, salicylic acid, and an alkyl hydroxamic acid having 5 to 9 carbon atoms, and Pb. 2+ Zn 2+ Al 3+ Cu 2+ Fe 2+ Fe 3+ At least one of the following is assembled in a mass ratio of 8:1 to 12:1. As a preferred embodiment, the upgrading flotation III employs a one-rougher, two-cleaner flotation process; wherein the rougher reagent regime is: 1500g / t to 2000g / t of fluorosilicic acid inhibitor-activator and 50g / t to 150g / t of amine collector; the primary cleaner reagent regime is: 1500g / t to 2000g / t of fluorosilicic acid inhibitor-activator and 10g / t to 30g / t of amine collector; and the secondary cleaner reagent regime is: 1500g / t to 2000g / t of fluorosilicic acid inhibitor-activator. Fluorosilicic acid, in addition to its inhibitory effect on silica minerals, also has a strong activating effect on pyrochlore and other minerals.

[0023] The weak magnetic field involved in this invention refers to a magnetic field strength of no more than 0.3T, and more preferably 0.15T~0.3T.

[0024] The strong magnet involved in this invention refers to a magnetic field strength exceeding 1.2T, more preferably 1.2T~1.5T.

[0025] The strongly magnetic iron ores involved in this invention refer to magnetite, ilmenite, maghematite, etc.

[0026] The magnetic niobium-bearing minerals involved in this invention refer to niobium minerals whose gangue minerals are mainly iron minerals, such as niobium iron minerals or niobium minerals with associated iron minerals.

[0027] The non-magnetic niobium-bearing minerals involved in this invention refer to niobium minerals whose gangue minerals are mainly silica-based minerals.

[0028] The efficient mineral processing involved in this invention refers to the efficient separation of niobium ore from silicon and iron minerals, so as to ensure that the total recovery rate of niobium ore reaches more than 60%, more preferably more than 64%, and the grade reaches more than 35%.

[0029] In the pharmaceutical formulation of this invention, the dosage of the pharmaceutical agent is relative to the mass of the raw ore added, that is, g / t (grams per ton) refers to the dosage of the pharmaceutical agent added relative to each ton of raw ore. Beneficial effects

[0030] Based on the phase composition and distribution characteristics of niobium ore, this invention separates niobium ore into magnetic niobium-bearing minerals and non-magnetic niobium-bearing minerals through magnetic separation. Combining the mineral characteristics of magnetic and non-magnetic niobium-bearing minerals, and fully considering the flotation separation behavior of impurities such as silicon and iron with niobium, a reasonable flotation process is designed to achieve efficient separation of niobium-bearing components in magnetic and non-magnetic minerals. This helps to ensure the overall niobium recovery rate, while improving the grade of niobium concentrate and reducing reagent consumption. Attached Figure Description

[0031] Figure 1 is a flow chart of the efficient niobium ore beneficiation process of the present invention. Embodiments of the present invention

[0032] The following specific embodiments are intended to further illustrate the content of the present invention, rather than to limit the scope of protection of the claims of the present invention.

[0033] Example 1

[0034] This experiment selected a niobium-bearing pyrochlore type ore as the research object. Table 1 below shows the main chemical composition of the niobium-bearing ore. Its composition is complex, and the content of valuable elements in the ore is low. The contents of Nb2O5 and TiO2 are 1.05% and 2.12%, respectively, and the total iron content is 11.52%.

[0035]

[0036] The specific experimental procedure is shown in Figure 1. As shown in Figure 1, after the raw ore is crushed, it is screened, and the coarse particles are returned to the crusher for further crushing. After crushing, the ore undergoes weak magnetic treatment, removing a portion of the strong magnetic concentrate under a magnetic field strength of 0.2T. Since fine-grained minerals are difficult to separate, the magnetic tailings need to be deslimed. The deslimed mineral samples are then subjected to strong magnetic separation under a magnetic field strength of 1.5T. The strong magnetic concentrate and strong magnetic tailings are separated by flotation according to their corresponding mineralogical characteristics. During the flotation of the strong magnetic concentrate, the influence of magnetic iron minerals on the niobium flotation behavior needs to be avoided. Therefore, the main method adopted is reverse flotation desilication pretreatment and amine acidic condition separation of niobium-containing minerals. The reagent system used for the main reverse flotation desilication is: NaOH pH=10, corn starch 500g / t, C 10 Etheramine acetate (commercial product) 200g / t. Reverse flotation desilication adopts one roughing stage, and the desilication tailings are dewatered and de-reagented, and further fine mud particles are removed before niobium mineral flotation test is carried out.

[0037] In the flotation of niobium-containing minerals, the main reagent system employed is: 2000 g / t of fluorosilicic acid, 50 g / t of defoamer P86, and 200 g / t of C16 saturated aliphatic diamine (commercial product). The main gangue minerals of pyrochlore are SiO2 and iron-bearing minerals. Therefore, in the flotation of niobium-containing minerals, pyrochlore can be separated from silica and iron-bearing minerals based on the surface electrical properties of the minerals.

[0038] The niobium flotation process mainly adopts a roughing and cleaning flotation process. The cleaning process uses fluorosilicic acid as a depressant. The reagent system for the first cleaning is: 2000 g / t of fluorosilicic acid depressant and 50 g / t of C16 saturated aliphatic diamine; the reagent system for the second cleaning is: 2000 g / t of fluorosilicic acid depressant; and the reagent system for the third cleaning is: 1500 g / t of fluorosilicic acid depressant.

[0039] In the flotation process of strongly magnetic tailings, the main method employs a hydroxamic acid-lead metal-based collector to enhance the collection of niobium-containing minerals. The roughing reagent regime is as follows: 100 g / t of tannic acid as a depressant, 50 g / t of lead nitrate and 500 g / t of hydroxamic acid as the collector, and 50 g / t of BK205 as the frother. In the cleaning stage, tannic acid is used as a depressant to gradually suppress silicate minerals, and the middlings are returned to the previous flotation stage. The reagent regime for the first cleaning stage is 50 g / t of tannic acid depressant; for the second cleaning stage, it is 25 g / t of tannic acid depressant; and for the third cleaning stage, it is 10 g / t of tannic acid depressant. After the roughing and cleaning flotation process, dewatering and dereagent removal are performed. Furthermore, a niobium collector is used for the upgrading and separation of niobium minerals. The reagent system used is 2000 g / t of fluorosilicic acid and 100 g / t of C16 saturated aliphatic diamine. The flotation process mainly consists of one roughing and two cleaning stages. The reagent system for the primary cleaning stage is 2000 g / t of fluorosilicic acid and 20 g / t of C16 saturated aliphatic diamine; the reagent system for the secondary cleaning stage is 2000 g / t of fluorosilicic acid.

[0040] The experimental results are shown in Table 2 below. The overall niobium flotation recovery rate was calculated based on the feed before magnetic separation. The results show that the grade of the niobium concentrate was significantly improved. The Nb₂O₅ grade in niobium concentrate 1 reached 38.27%, and in niobium concentrate 2 it reached 37.42%, a substantial increase compared to the original ore's 1.05% Nb₂O₅ content. Simultaneously, the overall niobium flotation recovery rate was also considerable, with niobium concentrate 1 achieving a recovery rate of 31.74% and niobium concentrate 2 achieving a recovery rate of 36.35%, totaling nearly 70%. This indicates that the beneficiation method of this invention can effectively enrich niobium minerals from low-grade pyrochlore-type niobium-bearing ore, achieving efficient separation of niobium-containing components from magnetic and non-magnetic minerals. While improving the niobium concentrate grade, it also ensures the niobium recovery rate, verifying the feasibility and effectiveness of this method in practical applications and providing strong technical support for the development and utilization of low-grade niobium resources.

[0041]

[0042] Example 2

[0043] This experiment selected a niobium-bearing pyrochlore-type ore, the same as that in Example 1, as the research object. Its composition is complex, and the content of valuable elements in the ore is low. Its Nb2O5 and TiO2 contents are 1.05% and 2.12%, respectively, and the total iron content is 11.52%.

[0044] The specific experimental procedure is the same as shown in Figure 1 below, but the reagent formulation differs. After crushing, the raw ore is screened, and the coarse particles are returned to the crusher for further crushing. The crushed ore undergoes weak magnetic treatment, removing a portion of the strong magnetic concentrate under a magnetic field strength of 0.2T. Since fine-grained minerals are difficult to separate, the magnetic tailings need to be deslimed. The deslimed mineral samples are then subjected to strong magnetic separation under a magnetic field strength of 1.5T. The strong magnetic concentrate and tailings are then separated by flotation according to their corresponding mineralogical characteristics. During the flotation of the strong magnetic concentrate, the influence of magnetic iron minerals on niobium flotation behavior must be avoided. Therefore, the main method employed is reverse flotation desilication pretreatment and amine-based acidic condition separation of niobium-containing minerals. The reagent formulation for the main reverse flotation desilication is: NaOH pH=10.5, corn starch 500g / t, C 10 Etheramine acetate (commercial product) 200g / t. Reverse flotation desilication adopts one roughing stage, and the desilication tailings are dewatered and de-reagented, and further fine mud particles are removed before niobium mineral flotation test is carried out.

[0045] In the flotation of niobium-containing minerals, the main reagent system used is: 2000 g / t of fluorosilicic acid, 50 g / t of defoamer P86, and 200 g / t of C18 saturated aliphatic diamine (commercial product). The main gangue minerals of pyrochlore are SiO2 and iron-bearing minerals. Therefore, in the flotation of niobium-containing minerals, pyrochlore can be separated from silica and iron-bearing minerals based on the surface electrical properties of the minerals.

[0046] The niobium flotation process mainly adopts a roughing and cleaning flotation process. The cleaning process uses fluorosilicic acid as a depressant. The reagent system for the first cleaning is: 2000 g / t of fluorosilicic acid depressant and 50 g / t of C18 saturated aliphatic diamine; the reagent system for the second cleaning is: 2000 g / t of fluorosilicic acid depressant; and the reagent system for the third cleaning is: 1500 g / t of fluorosilicic acid depressant.

[0047] In the flotation process of strongly magnetic tailings, the main method is to use a hydroxamic acid-lead metal-based collector to enhance the collection of niobium-containing minerals. During the roughing stage, 80 g / t of tannin inhibitor and a hydroxamic acid-lead complex collector (benzohydroxyxamic acid and Pb) are added. 2+ 440 g / t of tannin inhibitor (coordinated at a mass ratio of 10:1) and 50 g / t of frother BK205 were added. Three cleaning processes were performed using tannin inhibitors of 40 g / t, 20 g / t, and 8 g / t respectively, with middlings returned sequentially. After a roughing and cleaning flotation process, dehydration and reagent removal were carried out. Further upgrading and separation of niobium minerals were performed using a niobium collector. A roughing and cleaning process was adopted. The roughing process added 1800 g / t of fluorosilicic acid inhibitor-activator and 80 g / t of C18 saturated fatty diamine; the first cleaning process used 1800 g / t of fluorosilicic acid and 15 g / t of C18 saturated fatty diamine; the second cleaning process retained only 1800 g / t of fluorosilicic acid.

[0048] The experimental results are shown in Table 3 below. The Nb₂O₅ grade of niobium concentrate 1 was 37.89%, and the recovery rate was 29.85%; the Nb₂O₅ grade of niobium concentrate 2 was 36.54%, and the recovery rate was 34.72%, with a total recovery rate of 64.57%. Compared with Example 1, after adjusting the reagent dosage, the niobium concentrate grade decreased slightly, but the reagent consumption decreased, and the process stability improved, verifying the flexibility of this invention in parameter optimization.

[0049]

Claims

1. A highly efficient beneficiation method for niobium ore, characterized in that: Includes the following steps: 1) After crushing the niobium ore, weak magnetic treatment is performed to remove the strong magnetic iron ore. The weak magnetic tailings are deslimed and then subjected to strong magnetic treatment to obtain strong magnetic concentrate and strong magnetic tailings. 2) After pH adjustment, the strong magnetic concentrate is subjected to desilication reverse flotation with flotation reagents including starch inhibitors and ether amine collectors to obtain desilication tailings; 3) After dewatering, de-reagenting and desliming the desiliconized tailings, flotation reagents including fluorosilicic acid inhibitors and amine collectors are added to perform niobium flotation I to obtain niobium concentrate I; 4) Add flotation reagents, including silica mineral inhibitors and hydroxamic acid metal complex collectors, to the strongly magnetic tailings for niobium flotation II to obtain niobium concentrate II; 5) After dehydration and de-reagent treatment, niobium concentrate II is subjected to flotation III with flotation reagents including fluorosilicic acid inhibitor-activator and amine collector to obtain niobium concentrate III.

2. The efficient beneficiation method for niobium ore according to claim 1, characterized in that: The magnetic weakening treatment uses a magnetic field strength of 0.15T to 0.3T; The strong magnetic treatment uses a magnetic field strength of 1.2T to 1.5T.

3. The efficient beneficiation method for niobium ore according to claim 1, characterized in that: 2) Adjust the pH to 10-11.

4. The efficient beneficiation method for niobium ore according to claim 1, characterized in that: The desilication reverse flotation includes a primary roughing flotation process; The reagent formulation for the roughing process is as follows: starch inhibitors 300g / ton to 800g / ton, and ether amine collectors 100g / ton to 300g / ton.

5. A highly efficient beneficiation method for niobium ore according to claim 1, characterized in that: The niobium flotation I adopts a roughing and cleaning flotation process; in, The reagent formulation for the roughing process is as follows: fluorosilicic acid inhibitor 1500g / ton~2500g / ton, amine collector 100g / ton~300g / ton, and defoamer 30g / ton~80g / ton; The optimal formulation is as follows: fluorosilicic acid inhibitor 1500g / ton~2500g / ton, amine collector 30g / ton~80g / ton; The secondary selection of reagents is as follows: fluorosilicic acid inhibitor 1500g / ton~2500g / ton; The formulation for the three-stage selection of reagents is as follows: fluorosilicic acid inhibitor 1300g / ton to 1800g / ton.

6. A highly efficient beneficiation method for niobium ore according to claim 5, characterized in that: The amine collectors include aliphatic diamines with 10 to 20 carbon atoms.

7. A highly efficient beneficiation method for niobium ore according to claim 1, characterized in that: The niobium flotation II process adopts a roughing and cleaning flotation process; in, The reagent formulation for rough selection is as follows: 50g / ton to 150g / ton of silica mineral inhibitor, 300g / ton to 800g / ton of hydroxamic acid metal complex collector, and 30g / ton to 80g / ton of foaming agent; The optimal formulation is as follows: silicon mineral inhibitor 30g / ton to 80g / ton; The secondary selection reagent system is as follows: silicon mineral inhibitor 15g / ton to 35g / ton; The three-stage selection process for the reagent formulation is as follows: silicon mineral inhibitor 5g / ton to 15g / ton.

8. A highly efficient beneficiation method for niobium ore according to claim 7, characterized in that: The silicon-based mineral inhibitors include at least one of sodium hexametaphosphate, carboxymethyl cellulose, tannin, water glass, salinized water glass, sodium fluorosilicate, fluorosilicic acid, and starch. The hydroxamic acid organometallic complex collector comprises at least one of benzohydroxyxamic acid, salicylic acid, and an alkylhydroxyxamic acid having 5-9 carbon atoms, and Pb. 2+ Zn 2+ Al 3+ Cu 2+ Fe 2+ Fe 3+ At least one of them is assembled in a mass ratio of 8:1 to 12:

1.

9. A highly efficient beneficiation method for niobium ore according to claim 1, characterized in that: The quality-enhancing flotation III adopts a one-roughing and two-cleaning flotation process; in, The reagent formulation for the roughing process is as follows: 1500g / ton to 2000g / ton of fluorosilicic acid inhibitor-activator and 50g / ton to 150g / ton of amine collector; the reagent formulation for the primary cleaning process is as follows: 1500g / ton to 2000g / ton of fluorosilicic acid inhibitor-activator and 10g / ton to 30g / ton of amine collector. The secondary selection process uses a reagent formulation of fluorosilicic acid inhibitor-activator at a rate of 1500g / ton to 2000g / ton.

10. A highly efficient beneficiation method for niobium ore according to claim 9, characterized in that: The amine collectors include aliphatic diamines with 10 to 20 carbon atoms.

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