Method for recovering tantalum-niobium concentrate from spodumene flotation concentrate and method for recovering lithium

Abstract

The invention provides a method for recovering tantalum-niobium concentrate from spodumene flotation concentrate and a method for recovering lithium. The total mass content of tantalum and niobium in the spodumene flotation concentrate is more than five ten thousandths, and the method comprises the following steps: carrying out high-gradient wet magnetic separation on the spodumene flotation concentrate to select rough tantalum and niobium concentrate and magnetic separation tailings; the selected tantalum-niobium rough concentrate is subjected to grading treatment, fine-fraction rough concentrate and fine-silt-fraction rough concentrate are obtained, the granularity of the fine-fraction rough concentrate is larger than that of the fine-silt-fraction rough concentrate, and the mass ratio of the fine-fraction rough concentrate in the tantalum-niobium rough concentrate ranges from 70% to 80%; carrying out table gravity separation on the fine-fraction rough concentrate to obtain fine-fraction concentrate, fine-fraction middlings and fine-fraction tailings; and the fine-silt-grade rough concentrate is subjected to table gravity separation, fine-silt concentrate, fine-silt middlings and fine-silt tailings are obtained, tantalum and niobium are enriched in fine-grain concentrate and fine-silt concentrate, and lithium is enriched in magnetic separation tailings, fine-grain middlings, fine-grain tailings, fine-silt middlings and fine-silt tailings.

Description

Technical Field

[0001] The present invention relates to the technical field of polymetallic ore dressing, and particularly relates to a method for recovering tantalum-niobium concentrate from spodumene flotation concentrate and a method for recovering lithium. Background Art

[0002] In recent years, the rapidly developing new energy vehicles have driven the continuous expansion of the lithium industry. Therefore, the development of lithium resources in the upstream industry has gathered, and pegmatite-type lithium resources have received the most attention. Pegmatite-type lithium resources often occur with tantalum-niobium minerals. During the mining and dressing process of lithium mines, tantalum-niobium minerals will also be enriched to a certain extent. In the development of lithium-tantalum-niobium polymetallic symbiotic mines, there are many mines that recover tantalum-niobium minerals before lithium selection. Some mines do not comprehensively recover tantalum-niobium resources during the lithium selection process, resulting in waste of tantalum-niobium resources. In order to comprehensively recover and utilize tantalum-niobium resources, some enterprises extract tantalum-niobium from lithium smelting slag. However, the mineral composition of lithium smelting slag is complex, the content of tantalum-niobium is further reduced, and physical separation is difficult, resulting in a tantalum-niobium recovery rate of only about 30%, and the recovery rate is relatively low.

[0003] Currently, in the conventional ore dressing of lithium-tantalum-niobium symbiotic mines, after the ore is crushed, it is separated by the process of stage grinding, stage spiral chute + shaking table gravity separation to obtain tantalum-niobium mixed concentrate, and then it is further selected by a dry high-intensity magnetic separator to obtain tantalum-niobium concentrate meeting market requirements. The gravity separation tailings are then floated to obtain lithium concentrate. However, the tantalum-niobium grade in lithium-tantalum-niobium symbiotic ore is low, the ore treatment volume is large, the process is long, the land occupation area is large, the investment cost is large, and the electricity and water consumption are large, resulting in a relatively high production cost of tantalum-niobium concentrate, a large amount of gravity separation tailings, and relatively high environmental protection requirements. Summary of the Invention

[0004] In order to reduce the production cost of tantalum-niobium concentrate and relieve the environmental protection pressure in its production, the present invention provides a method for recovering tantalum-niobium concentrate from spodumene flotation concentrate and a method for recovering lithium.

[0005] The first aspect of the present invention provides a method for recovering tantalum-niobium concentrate from spodumene flotation concentrate, where the total mass content of tantalum and niobium in the spodumene flotation concentrate is more than five ten-thousandths. The method includes: performing high-gradient wet magnetic separation on the spodumene flotation concentrate to obtain tantalum-niobium rough concentrate and magnetic separation tailings; classifying the obtained tantalum-niobium rough concentrate to obtain fine-grained rough concentrate and fine-slime rough concentrate, where the particle size of the fine-grained rough concentrate is larger than that of the fine-slime rough concentrate, and the mass ratio of the fine-grained rough concentrate in the tantalum-niobium rough concentrate is between 70% and 80%; performing shaking table gravity separation on the fine-grained rough concentrate to obtain fine-grained concentrate, fine-grained middlings, and fine-grained tailings; performing shaking table gravity separation on the fine-slime rough concentrate to obtain fine-slime concentrate, fine-slime middlings, and fine-slime tailings. Tantalum and niobium are enriched in the fine-grained concentrate and the fine-slime concentrate, and lithium is enriched in the magnetic separation tailings, the fine-grained middlings, the fine-grained tailings, the fine-slime middlings, and the fine-slime tailings.

[0006] In any embodiment of the first aspect, a high-gradient wet magnetic separator is used to perform high-gradient wet magnetic separation on spodumene flotation concentrate. Preferably, the magnetic field strength for magnetic separation is 1.0T - 1.5T, and preferably the pulse frequency of the high-gradient wet magnetic separator is selected to be 30HZ - 40HZ.

[0007] In any embodiment of the first aspect, the spodumene flotation concentrate is subjected to magnetic separation with a pulp having a solid mass content of 20% - 30%.

[0008] In any embodiment of the first aspect, the classification treatment uses a particle size of 0.025mm as the classification boundary.

[0009] In any embodiment of the first aspect, a vibrating screen, a hydrocyclone or an air classifier is used for classification treatment.

[0010] In any embodiment of the first aspect, the table concentration of the fine-grained rough concentrate includes roughing and scavenging carried out successively.

[0011] In any embodiment of the first aspect, a 6s fine sand table is used to perform table concentration on the fine-grained rough concentrate.

[0012] In any embodiment of the first aspect, the table concentration of the fine slime rough concentrate is carried out once to obtain fine slime concentrate, fine slime middlings and fine slime tailings.

[0013] In any embodiment of the first aspect, a 6s slime table is used to perform table concentration on the fine slime rough concentrate.

[0014] In any embodiment of the first aspect, the spodumene flotation concentrate is pretreated before high-gradient wet magnetic separation. The pretreatment includes successively performing de-drug treatment and dispersion treatment on the spodumene flotation concentrate.

[0015] In any embodiment of the first aspect, the de-drug treatment includes:

[0016] Mixing the spodumene flotation concentrate with water to form a pulp having a solid mass content of 30% - 40%;

[0017] Mixing the pulp with a sulfuric acid solution and stirring until there are only foams in the central area of the surface of the pulp under the stirring state. Calculated based on the sulfuric acid solution with a mass concentration of 5%, the addition amount of the sulfuric acid solution relative to the pulp is 1000g / ton - 1500g / ton.

[0018] In any embodiment of the first aspect, there are no visible coarse particles in the pulp after the dispersion treatment is completed.

[0019] The second aspect of the present invention provides a method for recovering lithium from spodumene flotation concentrate, comprising: obtaining magnetic separation tailings, fine middlings, fine tailings, slime middlings and slime tailings by using any one of the methods provided in any implementation manner of the above first aspect; recovering lithium from the magnetic separation tailings, fine middlings, fine tailings, slime middlings and slime tailings.

[0020] The grades of tantalum and niobium in spodumene flotation concentrate are relatively high. Therefore, when using spodumene flotation concentrate as raw material to recover tantalum-niobium concentrate, the ore treatment volume is small, the crushing and grinding processes can be omitted, the process flow is short, the comprehensive recovery rate of tantalum and niobium is high, and the enrichment ratio is nearly 300 times or even more than 300 times. Through high-gradient wet magnetic separation treatment, the equipment occupies a small area and the overall investment cost is low. The obtained fine middlings, fine tailings, slime middlings and slime tailings can still be further processed to recover lithium and maintain a high lithium recovery rate.

[0021] Specifically, the particle size of spodumene flotation concentrate is fine. The recovery rates of screw chute separation and shaking table separation are low and the effects are not good. By utilizing the weak magnetic property of tantalum and niobium, high-gradient wet magnetic separation is used for magnetic separation, and the recovery rate of tantalum and niobium can reach about 82%, which is 30%-40% higher than that of other beneficiation methods. The particle size of tantalum and niobium in spodumene flotation concentrate is fine and the particle size distribution range is wide. Through experiments, it is found that when the mass ratio of fine-grained rough concentrate in tantalum-niobium rough concentrate is between 70%-80% as the classification boundary for classification, and the two separated products are respectively subjected to shaking table gravity separation, the recovery rate of tantalum and niobium can be improved targeted.

[0022] Term Explanation:

[0023] Wet magnetic separation: refers to a method of separating minerals by using the high-intensity magnetic field of a magnetic separation device during the beneficiation process, where mineral particles are suspended in a liquid medium (usually water).

[0024] Classification: refers to the process of dividing ore particles (ore grains) into several levels (grades) according to their particle sizes.

[0025] Shaking table: a beneficiation equipment that uses the combined action of mechanical shaking and water flow flushing to separate ore particles according to specific gravity.

[0026] Gravity separation: a beneficiation method that separates mineral particles according to the density (specific gravity) difference between mineral particles in a moving medium (such as water flow, air or heavy suspension), and makes the mineral particles stratify according to density and separates them through appropriate mechanical devices.

[0027] Spodumene flotation concentrate: is a product in which spodumene minerals are enriched after beneficiation process treatment. Brief Description of the Drawings

[0028] The accompanying drawings described herein are used to provide a further understanding of the present invention and form a part of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0029] Figure 1 A flowchart showing the recovery of tantalum and niobium concentrates from spodumene flotation concentrate in Embodiment 1 of the present invention is shown.

[0030] Figure 2 A flowchart showing the tabling re - separation of fine - sized rough concentrates using a LYN - 1100*500 type shaking table in Embodiment 2 of the present invention is shown.

[0031] Figure 3 A flowchart showing the tabling re - separation of fine - slime - sized rough concentrates using a 120 - grooved corrugated fine - slime shaking table in Embodiment 3 of the present invention is shown. Detailed implementation manners

[0032] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way restricts the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art. The terms used in the description of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term “and / or” used herein includes any and all combinations of one or more of the related listed items.

[0034] As analyzed in the background art of the present invention, currently, the production cost of recovering tantalum and niobium concentrates from lithium - tantalum - niobium symbiotic mines is high and the environmental protection pressure is great. To solve this problem, the present invention provides a method for recovering tantalum and niobium concentrates from spodumene flotation concentrate, wherein the total mass content of tantalum and niobium in the spodumene flotation concentrate is more than five ten - thousandths. The method includes:

[0035] Performing high - gradient wet magnetic separation on the spodumene flotation concentrate to select tantalum - niobium rough concentrates and magnetic separation tailings;

[0036] Classifying the selected tantalum - niobium rough concentrates to obtain fine - sized rough concentrates and fine - slime - sized rough concentrates. The particle size of the fine - sized rough concentrates is larger than that of the fine - slime - sized rough concentrates, and the mass proportion of the fine - sized rough concentrates in the tantalum - niobium rough concentrates is between 70% and 80%;

[0037] The fine-grained rough concentrate is subjected to table concentration to obtain fine concentrate, fine middlings and fine tailings;

[0038] The fine-slime rough concentrate is subjected to table concentration to obtain fine-slime concentrate, fine-slime middlings and fine-slime tailings. Tantalum and niobium are enriched in the fine concentrate and fine-slime concentrate, while lithium is enriched in the magnetic separation tailings, fine middlings, fine tailings, fine-slime middlings and fine-slime tailings.

[0039] The grade of tantalum and niobium in the spodumene flotation concentrate is relatively high. Therefore, when recovering tantalum and niobium concentrate using the spodumene flotation concentrate as raw material, the ore throughput is small, and the crushing and grinding processes can be omitted, resulting in a short process flow, high comprehensive recovery rate of tantalum and niobium, and an enrichment ratio of nearly 300 times or even more than 300 times. Through high-gradient wet magnetic separation treatment, the equipment occupies a small area and the overall investment cost is low. The obtained fine middlings, fine tailings, fine-slime middlings and fine-slime tailings can still be further processed to recover lithium with a high lithium recovery rate.

[0040] Specifically, the particle size of the spodumene flotation concentrate is fine, and the recovery rates of screw chute concentration and table concentration are low with poor effects. Utilizing the weak magnetic property of tantalum and niobium, high-gradient wet magnetic separation is used for magnetic separation, and the recovery rate of tantalum and niobium can reach about 82%, which is 30%-40% higher than that of other beneficiation methods. The particle size of tantalum and niobium in the spodumene flotation concentrate is fine and the particle size distribution range is wide. Through experiments, it is found that when the mass ratio of the fine-grained rough concentrate with a particle size greater than 0.025mm in the tantalum and niobium rough concentrate is between 70%-80% as the classification boundary for classification, and the two separated products are respectively subjected to table concentration, the recovery rate of tantalum and niobium can be improved targeted.

[0041] In some embodiments, a high-gradient wet magnetic separator is used to perform high-gradient wet magnetic separation on the spodumene flotation concentrate. Preferably, the magnetic field intensity for magnetic separation is 1.0T - 1.5T, and the pulse frequency of the high-gradient wet magnetic separator is preferably selected as 30HZ - 40HZ. Magnetic separation under the above magnetic field intensity can improve the tantalum and niobium enrichment ratio as much as possible under the condition of achieving a high recovery rate of tantalum and niobium. Too low a magnetic field intensity will result in a low recovery rate of tantalum and niobium, and too high a magnetic field intensity will lead to serious inclusion and a decrease in the tantalum and niobium enrichment ratio; magnetic separation under the above pulse frequency can effectively balance the enrichment ratio and recovery rate of tantalum and niobium in the rough concentrate. When the pulse frequency is too low, the inclusion is serious and the tantalum and niobium enrichment ratio decreases, and when the pulse frequency is too high, the recovery rate of tantalum and niobium decreases.

[0042] In some embodiments, in order to improve the magnetic separation efficiency, the spodumene flotation concentrate is subjected to magnetic separation with a pulp having a solid mass content of 20% - 30%.

[0043] In some embodiments, the classification treatment is carried out with a particle size of 0.025mm as the classification boundary. The mass ratio of the fine-grained rough concentrate with a particle size greater than 0.025mm in the tantalum and niobium rough concentrate is between 70% - 80%.

[0044] The present invention does not particularly limit the specific implementation means of classification treatment. In some embodiments, a vibrating screen, a hydrocyclone or an air classifier is used for classification treatment. Each of the above classification devices has its own advantages and disadvantages. For example, if the material to be classified is too fine and the mesh hole of the vibrating screen reaches 0.025 mm, the material is likely to be blocked, resulting in a relatively low screening efficiency; the settling space of the hydrocyclone of the hydrocyclone (such as the Yunnan Tin classification box) is small, the settling speed is slow, and the classification efficiency is relatively low. However, the classification efficiency can be improved to a certain extent by adjusting the equipment parameters during the specific classification treatment, etc.

[0045] After classification treatment, the particle size distribution of the fine-grained rough concentrate is relatively wide. In order to fully recover the tantalum and niobium therein, in some embodiments, the table concentration of the fine-grained rough concentrate includes the roughing and scavenging processes carried out successively. Utilizing the characteristic that the density of tantalum and niobium is significantly greater than the density of lithium, the fine-grained rough concentrate is roughed to obtain rough concentrate, rough middlings and rough tailings; then the rough middlings are continuously scavenged to obtain scavenged secondary concentrate and scavenged middlings. The combination of the rough concentrate and the scavenged secondary concentrate is the fine concentrate, the scavenged middlings are the fine middlings, and the rough tailings are the fine tailings. The grade of tantalum in the obtained fine concentrate is relatively high. In some embodiments, during the above-mentioned roughing and scavenging, the feed concentration is selected to be 15%-25%, the stroke is 12 mm-28 mm and / or the stroke frequency is 250 times / minute-450 times / minute.

[0046] When the grades of tantalum and niobium are insufficient after roughing and scavenging, in some embodiments, after roughing and scavenging, the combination of the rough concentrate and the scavenged secondary concentrate can also be beneficiated to obtain beneficiated concentrate, beneficiated secondary concentrate and beneficiated tailings. The beneficiated concentrate and the beneficiated secondary concentrate are the fine concentrate, the scavenged middlings and the beneficiated tailings are the fine middlings, and the rough tailings are the fine tailings.

[0047] The equipment for the table concentration of the above-mentioned fine-grained rough concentrate can be selected from conventional concentration equipment. For example, a 6s fine sand table is used for the table concentration of the fine-grained rough concentrate.

[0048] In some embodiments, the fine-slime rough concentrate is subjected to one-time table concentration to obtain fine-slime concentrate, fine-slime middlings and fine-slime tailings. Since the particle size distribution range of the fine-slime rough concentrate is relatively narrower than that of the fine-grained rough concentrate, only one-time table concentration is required. In some embodiments, the above-mentioned one-time table concentration selects a feed concentration of 15%-20%, a stroke of 8 mm-16 mm, and / or a stroke frequency of 300 times / minute-340 times / minute.

[0049] The equipment for the tabling concentration of the above-mentioned fine slime grade rough concentrate can be selected from conventional tabling equipment. Since the particle size in the fine slime grade rough concentrate is relatively small, it is easy to be lost during the tabling concentration process. It is preferably to use a grooved fine slime table for concentration. For example, a 6s slime table is used for the tabling concentration of the fine slime grade rough concentrate. It is preferably to use a 6s slime table with more than 120 grooving numbers for the tabling concentration of the fine slime grade rough concentrate. For example, a 6s slime table with 120 grooves or a 6s slime table with 138 grooves is selected.

[0050] The spodumene flotation concentrate used in the present invention comes from a conventional spodumene flotation process, and the present invention does not limit the spodumene flotation process. In some embodiments, when there are still a large amount of flotation reagents remaining in the spodumene flotation concentrate, the spodumene flotation concentrate can be pretreated to remove this part of the flotation reagents, thereby improving the magnetic separation efficiency. For example, the spodumene flotation concentrate is pretreated before high-gradient wet magnetic separation. The pretreatment includes performing a de-drug treatment and a dispersion treatment on the spodumene flotation concentrate in sequence. The de-drug treatment process removes the flotation reagents, and the dispersion treatment further refines the particles of the spodumene flotation concentrate, improving the magnetic separation efficiency and the magnetic separation effect.

[0051] In some embodiments, the de-drug treatment includes: mixing the spodumene flotation concentrate with water to form a pulp with a solid mass content of 30%-40%; mixing the pulp with a sulfuric acid solution and stirring until there are only foams in the central area on the surface of the pulp. Calculated by the sulfuric acid solution with a mass concentration of 5%, the addition amount of the sulfuric acid solution relative to the pulp is 1000 g / ton - 1500 g / ton. The sulfuric acid is used to neutralize the reagents in the spodumene flotation concentrate, and foams will be generated during the neutralization process. When there are only foams in the central area on the surface of the pulp under the stirring state, it means that the reagents are basically completely removed. The definition of the size of the above "central area" varies depending on the area of the pulp surface. The diameter of the central area can be defined as d, and the diameter of the stirring tank is D, and d = 1 / 4·D.

[0052] The purpose of the dispersion treatment is to eliminate the caking and agglomeration of coarse particles (particle size ≥ 0.5 - 1 mm) in the spodumene flotation concentrate powder due to long-term storage. These particles will affect the subsequent magnetic separation and tabling concentration. After the stirring in the above-mentioned de-drug treatment, the dispersion degree of the spodumene flotation concentrate in the pulp is also improved. There are various means for the dispersion treatment, such as mechanical stirring, magnetic stirring, etc. After the dispersion treatment is completed, there are no visible coarse particles in the pulp, that is, the dispersion treatment is judged to be completed based on the standard that there are no visible coarse particles in the pulp. The specific judgment method is based on the visual inspection of the taken pulp without visible coarse particles (including caking lumps).

[0053] After the recovery of tantalum and niobium, the remaining ore materials can still be used for lithium recovery. Therefore, the present invention further provides a method for recovering lithium from spodumene flotation concentrate, which includes:

[0054] Obtain magnetic separation tailings, fine middlings, fine tailings, slime middlings and slime tailings by any one of the above methods;

[0055] Recover lithium from magnetic separation tailings, fine middlings, fine tailings, slime middlings and slime tailings.

[0056] Directly concentrate the magnetic separation tailings, fine middlings, fine tailings, slime middlings and slime tailings into a spodumene concentrate pool, and further process and recover lithium according to the conventional lithium recovery process, so that the lithium recovery rate in the spodumene flotation concentrate reaches more than 99%.

[0057] The beneficial effects of the present invention will be further described below in conjunction with examples and comparative examples.

[0058] Example 1

[0059] The content of the main components in the spodumene flotation concentrate (i.e., the raw ore in the following table) is shown in Table 1.

[0060] Table 1

[0061] Component <![CDATA[Li2O]]> <![CDATA[Nb2O5]]> <![CDATA[Ta2O5]]> BeO <![CDATA[SiO2]]> <![CDATA[Fe2O3]]> Mass content 5.54 0.028 0.061 0.16 62.69 2.52 Component <![CDATA[Al2O3]]> <![CDATA[P2O5]]> MnO <![CDATA[K2O]]> <![CDATA[Na2O]]> CaO Mass content 22.88 0.29 0.44 0.59 0.47 2.04

[0062] Drug removal pretreatment: In a stirring tank, mix the spodumene flotation concentrate powder with water to form a pulp with a solid mass content of 35%, add dilute sulfuric acid with a concentration of 5%, and the addition amount is 1000 g / ton; the stirring speed is 200 - 250 revolutions per minute, and the stirring time is about 15 minutes, so that only a small amount of foam exists in the central area on the surface of the pulp under the stirring state.

[0063] Dispersion pretreatment: The pulp after achieving the purpose of drug removal is continuously stirred in the stirring tank for 10 minutes, and the taken-out pulp is visually inspected to have no coarse particles or agglomerated lumps that can be crushed by fingers visible to the naked eye.

[0064] High-gradient wet magnetic separation: Add water to adjust the pulp of the pretreated spodumene concentrate to a solid mass content of 25% - 30%, and use a vertical ring type 500 high-gradient wet magnetic separator to perform magnetic separation on the adjusted pulp. The magnetic field intensity is 1.0 T, and the pulse frequency is selected as 30 HZ to select tantalum-niobium rough concentrate and magnetic separation tailings. The particle size classification of the tantalum-niobium rough concentrate is recorded in Table 2.

[0065] Table 2

[0066] Particle size Yield / % +0.1 18.22 -0.1+0.075 17.39 -0.075+0.045 23.87 -0.045+0.025 16.34 -0.025+0.01 21.48 -0.01 2.70 Total 100.00

[0067] Classification treatment: The tantalum-niobium rough concentrate selected by magnetic separation is limited by a particle size of 0.025 mm, and is screened by an XSZ-600x300 type vibrating screen to separate the fine-grained rough concentrate and the slime-grained rough concentrate. The screening results of the fine-grained rough concentrate and the slime-grained rough concentrate are recorded in Table 3.

[0068] Table 3

[0069]

[0070] According to the screening results, the proportion of the +0.025 mm particle size fraction in the tantalum-niobium rough concentrate is 76.16%, and the proportion of tantalum occurring in the fine-grained concentrate is 52.04%, while the proportion of tantalum in the fine-slime concentrate is 47.96%.

[0071] For the tabling re-selection of the fine-grained rough concentrate (+0.025 mm coarse-grained product), the RK / LY-2011*1050 type table was used for tabling re-selection under the conditions of a feed concentration of 20%, a stroke of 18 mm, and a reciprocating frequency of 280 times per minute. Specifically, the rough selection of the fine-grained rough concentrate was carried out to obtain rough concentrate, rough middlings, and rough tailings; then, the rough middlings were further scavenged to obtain scavenging secondary concentrate and scavenging middlings. The combination of the rough concentrate and the scavenging secondary concentrate is the fine concentrate, the scavenging middlings are the fine middlings, and the rough tailings are the fine tailings. The test results are shown in Table 4.

[0072]

[0073] Table 4

[0074]

[0075] For the tabling re-selection of the fine-slime rough concentrate (-0.025 mm fine-grained product):

[0076] The 6-S4.5 type 138-grooved fine-slime table was used for tabling re-selection under the conditions of a feed concentration of 15%, a stroke of 10 mm, and a reciprocating frequency of 300 times per minute to obtain fine-slime concentrate, fine-slime secondary concentrate, fine-slime middlings, and fine-slime tailings. The test results are shown in Table 5.

[0077] Table 5

[0078]

[0079] According to the test results, the tantalum-niobium concentrate with a Ta2O5 content of 20.05% and a recovery rate of 10.59% for the original ore, and the tantalum-niobium secondary concentrate with a Ta2O5 content of 7.19% and a recovery rate of 13.87% for the original ore can be obtained by using the above-mentioned tabling re-selection for the fine-slime rough concentrate.

[0080] The results of each product in the above-mentioned whole process are shown in Table 6.

[0081] Table 6

[0082]

[0083] ​In the full process flow chart and in Table 6, there is no secondary concentrate in the shaking table separation of fine-grained rough concentrate. The main reason is that the rough concentrate and the scavenging secondary concentrate are blended in a ratio of 1:1. After mixing, the Ta2O5 content in the fine-grained concentrate reaches 21.94%, fully meeting the quality requirements of tantalum-niobium concentrate produced domestically, that is, the Ta2O5 content in the concentrate is greater than 15%.

[0084] Example 2

[0085] The difference from Example 1 lies in the shaking table gravity separation of fine-grained rough concentrate (+0.025mm coarse-grained product): The shaking table gravity separation is carried out using a LYN-1100*500 type shaking table. Specifically, as Figure 2 shown, the rough separation of the fine-grained rough concentrate is carried out to obtain rough concentrate and rough tailings; then the rough tailings are continuously scavenged to obtain scavenging concentrate, scavenging secondary concentrate and scavenging middlings. The combined rough concentrate, scavenging concentrate and scavenging secondary concentrate are subjected to cleaning to obtain cleaning concentrate, cleaning secondary concentrate and cleaning tailings. The cleaning concentrate and cleaning secondary concentrate are used as fine-grained concentrate, and the scavenging middlings and cleaning tailings are used as fine-grained middlings. The rough tailings are the fine-grained tailings. The test results are shown in Table 7.

[0086] Table 7

[0087]

[0088] Using the LYN-1100*500 type shaking table for gravity separation can obtain fine-grained concentrate with a Ta2O5 content of 36.50% and a recovery rate of 22.73% for the original ore, and fine-grained secondary concentrate with a Ta2O5 content of 8.31% and a recovery rate of 6.71% for the original ore.

[0089] Example 3

[0090] The difference from Example 1 lies in the shaking table gravity separation of fine-slime rough concentrate (-0.025mm coarse-grained product): As Figure 3 shown, the 6-S4.5 type 120-groove corrugated fine-slime shaking table is used for shaking table gravity separation under the conditions of a feeding concentration of 15%, a stroke of 10mm, and a reciprocating frequency of 300 times per minute to obtain fine-slime concentrate, fine-slime middlings and fine-slime tailings. The test results are shown in Table 8.

[0091] Table 8

[0092]

[0093] Using the 120-groove corrugated fine-slime shaking table for cleaning can obtain fine-slime concentrate with a Ta2O5 content of 5.30%, an operating recovery rate of 68.78%, and a recovery rate of 56.91% for the original ore.

[0094] The above has described the exemplary embodiments of the present invention. However, the protection scope of the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc. made by those skilled in the art within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for recovering tantalum-niobium concentrate from spodumene flotation concentrate, wherein: The total mass content of tantalum and niobium in the spodumene flotation concentrate is more than 0.5 parts per million, and the method comprises: The spodumene flotation concentrate is subjected to high-gradient wet magnetic separation to select tantalum-niobium rough concentrate and magnetic separation tailings; The selected tantalum-niobium rough concentrate is subjected to classification treatment to obtain a fine-grained rough concentrate and a fine-mud-grade rough concentrate, wherein the particle size of the fine-grained rough concentrate is greater than that of the fine-mud-grade rough concentrate, and the mass proportion of the fine-grained rough concentrate in the tantalum-niobium rough concentrate is between 70% and 80%; The fine-grained coarse concentrate is subjected to a shaking table gravity separation to obtain a fine-grained concentrate, a fine-grained middling ore and a fine-grained tailings; The fine mud-grade coarse concentrate is subjected to shaking table gravity separation to obtain fine mud concentrate, fine mud middlings and fine mud tailings, wherein the fine-grained concentrate and the fine mud concentrate are enriched with tantalum and niobium, and the magnetic separation tailings, fine middlings, fine tailings, fine mud middlings and the fine mud tailings are enriched with lithium.

2. The method according to claim 1, wherein: The spodumene flotation concentrate is subjected to high gradient wet magnetic separation using a high gradient wet magnetic separator, wherein the magnetic field strength of the magnetic separation is preferably 1.0T-1.5T, and the pulse frequency of the high gradient wet magnetic separator is preferably 30HZ-40HZ.

3. The method according to claim 1 or 2, wherein: The spodumene flotation concentrate is subjected to magnetic separation using a pulp having a solid mass content of 20% to 30%.

4. The method according to any one of claims 1 to 3, wherein: The classification process uses a particle size of 0.025 mm as the classification limit.

5. The method according to any one of claims 1 to 4, wherein: The classification process is carried out by using a vibrating screen, a hydrocyclone or an air flow classifier.

6. The method according to any one of claims 1 to 5, wherein: The shaking table gravity separation of the fine-grained coarse concentrate includes roughing separation and scavenging separation carried out successively.

7. The method according to any one of claims 1 to 6, wherein: A 6s fine sand shaking table is used to conduct shaking table gravity separation on the fine-grained coarse concentrate.

8. The method according to any one of claims 1 to 7, wherein: The fine mud coarse concentrate is subjected to a shaking table gravity separation to obtain fine mud concentrate, fine mud middlings and fine mud tailings.

9. The method according to any one of claims 1 to 8, wherein: A 6s ore mud shaker is used to conduct shaker gravity separation on the fine mud coarse concentrate.

10. The method according to any one of claims 1 to 9, wherein: The spodumene flotation concentrate is pretreated before high-gradient wet magnetic separation, and the pretreatment includes sequentially performing drug removal treatment and dispersion treatment on the spodumene flotation concentrate.

11. The method according to claim 10, wherein: The drug removal process comprises: Mixing the spodumene flotation concentrate with water to form a slurry having a solid mass content of 30% to 40%; The ore pulp and the sulfuric acid solution are mixed and stirred until foam exists only in the central area of ​​the surface of the ore pulp under stirring. Based on a sulfuric acid solution with a mass concentration of 5%, the amount of the sulfuric acid solution added relative to the ore pulp is 1000g / ton-1500g / ton.

12. The method according to claim 10 or 11, wherein: After the dispersion treatment is completed, there are no coarse particles visible to the naked eye in the slurry.

13. A method for recovering lithium from spodumene flotation concentrate, wherein: Said include: Utilizing the method according to any one of claims 1 to 12 to obtain magnetic separation tailings, fine-grained medium ore, fine-grained tailings, fine-mud medium ore and fine-mud tailings; Lithium is recovered from the magnetic separation tailings, fine-grained middlings, fine-grained tailings, fine mud middlings and fine mud tailings.

Images