CN116727100A - Beneficiation method for low-grade clay type lithium ore - Google Patents

Abstract

The present invention relates to the technical field of mineral processing, and in particular to a mineral processing method for low-grade clay-type lithium ore. An ore dressing method for low-grade clay-type lithium ore, including the following steps: (a) performing a cleaning process on the low-grade clay-type lithium ore to obtain ore; (b) performing a classification process on the ore to obtain coarse-grained minerals and fine-grained minerals grade minerals; (c) perform the first desliming process on the coarse-grained minerals to obtain coarse-grained slurry; perform the second desliming process on the fine-grained minerals to obtain fine-grained slurry; (d) conduct the coarse-grained slurry Reverse flotation and dealumination are performed to obtain tailings and bauxite; the mixture obtained by mixing the tailings and fine-grained slurry is subjected to reverse flotation and desilication to obtain lithium concentrate. The mineral processing method of the present invention is applied to low-grade clay-type lithium ore, which can not only effectively improve the grade and recovery rate of lithium ore, but also obtain by-products such as bauxite, magnetite, kaolin, etc., which have high utilization value, greatly improving the Utilization value of low-grade clay-based lithium ores.

Description

A method for beneficiating low-grade clay-type lithium ore

Technical Field

The invention relates to the technical field of ore dressing, and in particular to a ore dressing method for low-grade clay-type lithium ore.

Background Art

In recent years, with the rapid development of the lithium battery industry, people's demand for lithium resources has increased rapidly, which has led to the continuous increase in the development of lithium resources. At present, lithium resources are mainly found in salt lakes and granite pegmatite deposits. Although the cost of extracting lithium from salt lakes is relatively low, the lithium resources of salt lakes are mostly distributed in plateau areas with poor development conditions. In addition, the current process conditions for extracting lithium from salt lakes have not been perfected and large-scale industrial production has not yet been achieved. Therefore, the current pattern of lithium salt production mainly using lithium ore as raw materials is difficult to change in the short term.

my country's lithium ore resources are mainly spodumene, which is characterized by high grade. There are relatively mature flotation processes on the market. Some lithium ore resources are also mixed in clay ores, mainly lithium chlorite in pegmatite aluminosilicate minerals; for this type of mineral, lithium resources are evenly distributed in the ore, and the main characteristics are high slurry viscosity, low grade, low aluminum silicon ratio, and low by-product utilization value. The traditional single flotation scheme is difficult to improve the grade of lithium ore in a targeted manner, and the recovery rate is low.

In view of this, the present invention is proposed.

Summary of the invention

The object of the present invention is to provide a method for beneficiating low-grade clay-type lithium ore, so as to solve the technical problems of low recovery rate and low grade of lithium ore in the beneficiation of low-grade clay-type lithium ore in the prior art.

In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

A method for beneficiating low-grade clay-type lithium ore comprises the following steps:

(a) subjecting low-grade clay-type lithium ore to a cleaning process to obtain ore;

(b) subjecting the ore to a classification process to obtain coarse-grained minerals and fine-grained minerals;

(c) performing a first desliming process on the coarse-grained mineral to obtain a coarse-grained ore pulp; performing a second desliming process on the fine-grained mineral to obtain a fine-grained ore pulp;

(d) subjecting the coarse-grained slurry to reverse flotation to remove aluminum to obtain tailings and bauxite; and subjecting the tailings to reverse flotation to remove silicon from the mixture obtained by mixing the fine-grained slurry to obtain lithium concentrate.

In a specific embodiment of the present invention, the reverse flotation dealumination step further comprises using a collector to collect the coarse-grained ore pulp.

In a specific embodiment of the present invention, the collector includes a hydroxamic acid collector and a carboxylic acid collector, and the mass ratio of the hydroxamic acid collector to the carboxylic acid collector is (1-3) : 1. Furthermore, the amount of the collector is 800-1200 g/t.

In a specific embodiment of the present invention, the hydroxamic acid collector includes at least one of octanoyl hydroxamic acid, octyl isohydroxamic acid, benzohydroxamic acid, salicylic hydroxamic acid and hydroxamic acid.

In a specific embodiment of the present invention, the carboxylic acid collector includes at least one of oleic acid, sodium oleate and oxidized paraffin soap.

In a specific embodiment of the present invention, the mineral processing method further comprises obtaining magnetic minerals by a magnetic separation process.

In a specific embodiment of the present invention, the ore pulp containing the lithium concentrate after reverse flotation desiliconization is subjected to a magnetic separation process to obtain the lithium concentrate and the magnetic mineral.

In a specific embodiment of the present invention, the coarse-grained mineral is subjected to a magnetic separation process to obtain the coarse-grained mineral after magnetic separation and the magnetic mineral; the fine-grained mineral is subjected to a magnetic separation process to obtain the fine-grained mineral after magnetic separation and the magnetic mineral. The magnetic mineral can be recycled.

In a specific embodiment of the present invention, the coarse-grained slurry is subjected to a magnetic separation process to obtain the coarse-grained slurry after magnetic separation and the magnetic mineral; the fine-grained slurry is subjected to a magnetic separation process to obtain the fine-grained slurry after magnetic separation and the magnetic mineral.

In a specific embodiment of the present invention, the reverse flotation dealumination step comprises: adding an adjuster, a pH adjuster, an inhibitor, an activator and a collector to the coarse particle size slurry in sequence. Further, the reverse flotation dealumination process comprises one coarse-one scavenging-one fine, one coarse-two scavenging-one fine or one coarse-two scavenging-two fine.

In a specific embodiment of the present invention, the adjusting agent includes sodium carbonate; the amount of the adjusting agent is 1000-1500 g/t.

In a specific embodiment of the present invention, the pH adjuster includes any one or more of sodium hydroxide, sodium carbonate and calcium hydroxide; the pH adjuster is added to make the pH of the coarse-grained slurry reach 8 to 9.6. Furthermore, the amount of the pH adjuster is 800 to 1200 g/t.

In a specific embodiment of the present invention, the inhibitor includes any one or more of sodium silicate, sodium hexametaphosphate, carboxymethyl cellulose, starch and dextrin; the dosage of the inhibitor is 100-150 g/t.

In a specific embodiment of the present invention, the activator includes any one or more of calcium chloride, aluminum chloride, ferric chloride and magnesium chloride; the amount of the activator is 80-200 g/t.

In a specific embodiment of the present invention, the reverse flotation desiliconization step comprises: adding a desiliconization regulator, a desiliconization activator and a desiliconization collector to the mixture in sequence. Further, the reverse flotation desiliconization process comprises one roughing and one sweeping, one roughing and two sweeping or one roughing and three sweeping.

In a specific embodiment of the present invention, the desiliconizing agent comprises any one or more of sulfuric acid, acetic acid and hydrofluoric acid; the desiliconizing agent is added to make the pH of the mixture reach 5 to 7. Furthermore, the amount of the desiliconizing agent is 1500 to 2000 g/t.

In a specific embodiment of the present invention, the desiliconization activator includes any one or more of sodium chloride, sodium fluoride and sodium fluorosilicate; the dosage of the desiliconization activator is 150-200 g/t.

In a specific embodiment of the present invention, the desiliconizing collector includes any one or more of dodecylamine, hexadecylamine, octadecylamine, dodecyltrimethylammonium chloride and hexadecyltrimethylammonium bromide; the amount of the desiliconizing collector is 500-800g/t.

In a specific embodiment of the present invention, the classification process includes: crushing the ore and then dividing it into the coarse-grained mineral and the fine-grained mineral through a classification device; the particle size difference of the ore after crushing is 0.15-0.32 mm. Furthermore, the ore crushing time is 5-8 minutes.

In a specific embodiment of the present invention, the steps of the first desliming process include: performing a first crushing on the coarse-grained mineral to obtain a coarse-grained pre-deslimed slurry, and then performing a first desliming treatment to obtain the coarse-grained slurry; the steps of the second desliming process include: performing a second crushing on the fine-grained mineral to obtain a fine-grained pre-deslimed slurry, and then performing a second desliming treatment to obtain the fine-grained slurry.

In a specific embodiment of the present invention, the particle size of the coarse-grained pre-demud pulp and/or the fine-grained pre-demud pulp is less than 0.074 mm; the proportion of particle size less than 0.074 mm is 80% to 85%; the concentration of the coarse-grained pre-demud pulp and/or the fine-grained pre-demud pulp is 10% to 12%.

In a specific embodiment of the present invention, the first desliming treatment and/or the second desliming treatment comprises any one of equipment desliming, free sedimentation desliming and flotation desliming; the time of the first crushing and/or the second crushing is 10 to 12 minutes.

In a specific embodiment of the present invention, the magnetic separation process includes: adjusting the concentration of the material to be magnetically separated to 10% to 15%, setting the magnetic field strength to 1.1 to 1.2 T, the feeding time to 50 to 80 s, the intermediate punching time to 30 to 60 s, and the fine punching time to 30 to 60 s.

In a specific embodiment of the present invention, the steps of the cleaning process include: coarsely crushing, cleaning and drying the low-grade clay-type lithium ore in sequence; further, the particle size of the coarsely crushed particles is 5 to 10 cm.

In a specific embodiment of the present invention, the grade of the lithium concentrate obtained by the ore dressing method is ≥1.40%, and the grade of the bauxite is ≥70%.

In a specific embodiment of the present invention, the aluminum-silicon ratio of the bauxite is greater than 5, and the grade of the magnetic mineral is greater than or equal to 30%.

In a specific embodiment of the present invention, the recovery rate of the lithium concentrate is 35% to 42%.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The ore dressing method of the present invention has the advantages of simple process, easy operation, strong pertinence, good flotation effect, etc., and can successfully solve the problems of flotation extraction of lithium from low-grade clay-type lithium ore, high slurry viscosity, low grade, low recovery rate, and high reagent cost. The ore dressing method of the present invention is applied to low-grade clay-type lithium ore, which can not only effectively improve the grade and recovery rate of lithium ore, but also the obtained by-products such as bauxite, magnetite, kaolin, etc. have high utilization value, which greatly improves the utilization value of low-grade clay-type lithium ore.

(2) The present invention adopts a specific collector in the flotation process, and aims at a specific flotation system, so that the collector can achieve an appropriate collection capacity, while ensuring the grade and recovery rate of the lithium concentrate.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of a process flow of a mineral processing method according to Embodiment 1 of the present invention;

FIG2 is a schematic diagram of a process flow of a mineral processing method according to Embodiment 2 of the present invention;

FIG3 is a schematic diagram of the process flow of the mineral processing method provided in Example 3 of the present invention.

DETAILED DESCRIPTION

The technical scheme of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments, but it will be appreciated by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work, all belong to the scope of protection of the present invention. If the specific conditions are not indicated in the embodiments, they are carried out according to the normal conditions or the conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

A method for beneficiating low-grade clay-type lithium ore comprises the following steps:

(a) subjecting low-grade clay-type lithium ore to a cleaning process to obtain ore and red mud impurities;

(b) subjecting the ore to a classification process to obtain coarse-grained minerals and fine-grained minerals;

(c) performing a first desliming process on the coarse-grained mineral to obtain a coarse-grained slurry and a first slurry impurity; performing a second desliming process on the fine-grained mineral to obtain a fine-grained slurry and a second slurry impurity;

(d) subjecting the coarse-grained slurry to reverse flotation to remove aluminum to obtain tailings and bauxite; and subjecting the tailings to reverse flotation to remove silicon from the mixture obtained by mixing the fine-grained slurry to obtain lithium concentrate.

The ore dressing method of the present invention removes various gangue minerals in the ore through targeted process flow according to the difference in mineral properties and mineral contents of different particle sizes, firstly performs a cleaning process on the low-grade minerals, then performs a classification process on the cleaned minerals, then performs a desliming process on the classified minerals, then performs a reverse flotation dealumination process on the treated coarse-grained ore pulp, and the obtained tailings are combined with the fine-grained ore pulp to perform a reverse flotation desiliconization process, etc., to obtain lithium concentrate and by-products such as bauxite, magnetite (i.e., magnetic mineral), kaolin, etc., wherein the bauxite meets the secondary standard of Bayer process for extracting alumina, the magnetite can be leached to prepare iron phosphate, and the kaolin can provide raw materials for refractory materials, cement, etc.

Among them, the main components of red mud impurities are aragonite and calcite, containing a small amount of ferric oxide, showing a light red color. The main component of the first ore mud impurities is diaspore, and also contains a small amount of CaO, MgO, _SiO2 impurities. The main components of the second ore mud impurities are quartz, chlorite, etc.

In a specific embodiment of the present invention, the reverse flotation dealumination step further includes using a collector to collect the coarse-grained slurry and/or the fine-grained slurry.

In a specific embodiment of the present invention, the collector includes a hydroxamic acid collector and a carboxylic acid collector, and the mass ratio of the hydroxamic acid collector to the carboxylic acid collector is (1-3) : 1. Furthermore, the amount of the collector is 800-1200 g/t.

The collector is a compound of hydroxamic acid collector and carboxylic acid collector. Hydroxamic acid contains alkaline functional groups, which can selectively chelate with Al under alkaline conditions and has strong selectivity; carboxylic acid collectors contain carboxyl functional groups, which can form fat-like compounds such as aluminum carboxylate with Al under alkaline conditions and have strong collecting ability; the two are compounded in a certain proportion to ensure both the selectivity and collecting ability for Al, thereby ensuring the recovery rate and grade of lithium concentrate.

In a specific embodiment of the present invention, the hydroxamic acid collector includes at least one of octanoyl hydroxamic acid, octyl isohydroxamic acid, benzohydroxamic acid, salicylic hydroxamic acid and hydroxamic acid.

In a specific embodiment of the present invention, the carboxylic acid collector includes at least one of oleic acid, sodium oleate, and oxidized paraffin soap.

For example, in different embodiments, the mass ratio of the hydroxamic acid collector to the carboxylic acid collector can be 1:1, 1.2:1, 1.5:1, 1.8:1, 2:1, 2.2:1, 2.5:1, 2.8:1, 3:1 or any range consisting of two of them; the dosage of the collector can be 800g/t, 900g/t, 1000g/t, 1100g/t, 1200g/t or any range consisting of two of them.

The ore dressing method of the present invention also includes obtaining magnetite by a magnetic separation process, and the magnetic separation process can be after the reverse flotation desiliconization process, after the classification process and before the desliming process, or after the desliming process, and can be adjusted according to the actual situation of the mineral. Specifically, the magnetic separation process can be any of the following situations:

The slurry containing lithium concentrate after reverse flotation desiliconization is subjected to a magnetic separation process to obtain lithium concentrate and magnetic minerals;

Alternatively, after the classification process, the coarse-grained mineral is adjusted into a pulp and subjected to a magnetic separation process to obtain a coarse-grained pulp after magnetic separation and the magnetic mineral; the fine-grained mineral is subjected to a magnetic separation process to obtain a fine-grained pulp after magnetic separation and the magnetic mineral;

Alternatively, after the desludging process, the coarse-grained slurry is subjected to a magnetic separation process to obtain the coarse-grained slurry and the magnetic mineral after magnetic separation; the fine-grained slurry is subjected to a magnetic separation process to obtain the fine-grained slurry and the magnetic mineral after magnetic separation.

In the above steps, the magnetic minerals removed by the magnetic separation process can be recycled. Wherein, the magnetic minerals include magnetite, and the magnetite includes hematite.

The difference in the position of the magnetic separation process will affect the recovery rate of lithium concentrate. If the magnetic separation process is in the front, there will be more mechanical entrainment, which may affect the recovery rate of lithium concentrate. When there is less magnetite (hematite) in the mineral, the effect is not significant. When the content of magnetite (hematite) in the mineral is relatively high, the difference in the position of the magnetic separation process will greatly affect the final recovery rate of lithium concentrate. Therefore, it is preferred to carry out a magnetic separation process on the slurry containing lithium concentrate after the reverse flotation desiliconization to obtain lithium concentrate and magnetic minerals.

In a specific embodiment of the present invention, the reverse flotation dealumination step includes: adding an adjuster, a pH adjuster, an inhibitor, an activator and a collector to the coarse particle size slurry in sequence. Further, the reverse flotation dealumination process steps include one coarse-one scavenging-one fine, one coarse-two scavenging-one fine or one coarse-two scavenging-two fine. Among them, the process steps of one coarse-one scavenging-one fine are commonly used technical means in mineral processing technology and are not described in detail in this application.

In actual operation, the concentration of the coarse-grained ore pulp is first adjusted to 10% to 12%, and then the above-mentioned reverse flotation dealumination operation is carried out.

In a specific embodiment of the present invention, the adjusting agent includes sodium carbonate; the amount of the adjusting agent is 1000-1500 g/t.

For example, in different embodiments, the amount of the regulator can be 1000 g/t, 1100 g/t, 1200 g/t, 1300 g/t, 1400 g/t, 1500 g/t or a range consisting of any two thereof.

In a specific embodiment of the present invention, the pH adjuster includes any one or more of sodium hydroxide, sodium carbonate and calcium hydroxide; the pH adjuster is added to make the pH of the coarse-grained slurry reach 8 to 9.6. Furthermore, the amount of the pH adjuster is 800 to 1200 g/t.

For example, in different embodiments, a pH adjuster can be added to make the pH of the coarse-grained slurry reach a range of 8, 8.2, 8.5, 8.8, 9, 9.2, 9.5, 9.6 or any two of them; the amount of the pH adjuster can be 800 g/t, 900 g/t, 1000 g/t, 1100 g/t, 1200 g/t or any two of them.

In a specific embodiment of the present invention, the inhibitor includes any one or more of sodium silicate, sodium hexametaphosphate, carboxymethyl cellulose, starch and dextrin; the dosage of the inhibitor is 100-150 g/t.

For example, in different embodiments, the dosage of the inhibitor may be 100 g/t, 110 g/t, 120 g/t, 130 g/t, 140 g/t, 150 g/t or a range consisting of any two thereof.

In a specific embodiment of the present invention, the activator includes any one or more of calcium chloride, aluminum chloride, ferric chloride and magnesium chloride; the amount of the activator is 80-200 g/t.

For example, in different embodiments, the amount of the activator can be 80 g/t, 100 g/t, 120 g/t, 150 g/t, 180 g/t, 200 g/t or a range consisting of any two thereof.

In a specific embodiment of the present invention, the reverse flotation desiliconization step comprises: adding a desiliconization regulator, a desiliconization activator and a desiliconization collector to the mixture in sequence. Further, the reverse flotation desiliconization process comprises one roughing and one sweeping, one roughing and two sweeping or one roughing and three sweeping.

In a specific embodiment of the present invention, the desiliconizing agent comprises any one or more of sulfuric acid, acetic acid and hydrofluoric acid; the desiliconizing agent is added to make the pH of the mixture reach 5 to 7. Furthermore, the amount of the desiliconizing agent is 1500 to 2000 g/t.

For example, in different embodiments, a desiliconizing adjuster can be added to make the pH of the mixture reach a range of 5, 5.2, 5.5, 5.8, 6, 6.2, 6.5, 6.8, 7 or any range consisting of two thereof; the amount of the desiliconizing adjuster can be 1500 g/t, 1600 g/t, 1700 g/t, 1800 g/t, 1900 g/t, 2000 g/t or any range consisting of two thereof.

Reverse flotation desiliconization needs to be carried out in an acidic environment, and reverse flotation dealumination needs to be carried out in an alkaline environment. The coarse-grained slurry is first subjected to reverse flotation dealumination to obtain tailings, and then the tailings and fine-grained slurry are subjected to reverse flotation desiliconization to ensure the reagent stability of the reverse flotation process steps, thereby ensuring the flotation index of lithium oxide.

In a specific embodiment of the present invention, the desiliconization activator includes any one or more of sodium chloride, sodium fluoride and sodium fluorosilicate; the dosage of the desiliconization activator is 150-200 g/t.

For example, in different embodiments, the amount of the desiliconization activator may be 150 g/t, 160 g/t, 170 g/t, 180 g/t, 190 g/t, 200 g/t or any range consisting of both.

In a specific embodiment of the present invention, the desiliconizing collector includes any one or more of dodecylamine, hexadecylamine, octadecylamine, hexadecyltrimethylammonium chloride and hexadecyltrimethylammonium bromide; the amount of the desiliconizing collector is 500-800g/t.

For example, in different embodiments, the amount of the desiliconization collector can be 500 g/t, 550 g/t, 600 g/t, 650 g/t, 700 g/t, 750 g/t, 800 g/t or a range consisting of any two thereof.

In the present invention, in the reverse flotation dealumination, the dosage of each additive refers to the dosage relative to the coarse-grained slurry with adjusted slurry concentration; in the reverse flotation desiliconization, the dosage of each additive refers to the dosage relative to the mixture of tailings and the fine-grained slurry. Taking the collector as an example, its dosage of 800-1200g/t means that the dosage of the collector is 800-1200g for every 1t of coarse-grained slurry, and the same applies to the other additives.

In a specific embodiment of the present invention, the classification process includes: crushing the ore and then dividing it into coarse-grained minerals and fine-grained minerals through a classification device; the particle size difference of the ore after crushing is 0.15-0.32 mm. Furthermore, the ore crushing time is 5-8 minutes.

In actual operation, the ore obtained in step (a) is sent to a grinding device for crushing for 5 to 8 minutes, and the particle size difference is 0.15 to 0.32 mm; the crushed minerals are sent to a grading device for grading. Among them, the oversize is the coarse-grained mineral, including minerals with higher hardness such as diaspore and quartz; the undersize is the fine-grained mineral, including aluminosilicate minerals with lower hardness. The grinding equipment includes a rod mill or a ball mill, and the grading equipment includes a cylindrical screen. The grading process is mainly carried out based on the hardness difference of the ore.

In a specific embodiment of the present invention, the steps of the first desliming process include: performing a first crushing on the coarse-grained mineral to obtain a coarse-grained pre-deslimed slurry, and then performing a first desliming treatment to obtain the coarse-grained slurry; the steps of the second desliming process include: performing a second crushing on the fine-grained mineral to obtain a fine-grained pre-deslimed slurry, and then performing a second desliming treatment to obtain the fine-grained slurry.

In a specific embodiment of the present invention, the particle size of the coarse-grained pre-demud pulp and/or the fine-grained pre-demud pulp is less than 0.074 mm; the proportion of particles less than 0.074 mm is 80% to 85% (i.e., 80% to 85% of particles sieved below 200 meshes); the concentration of the coarse-grained pre-demud pulp and/or the fine-grained pre-demud pulp is 10% to 12%. The concentration of the coarse-grained pre-demud pulp and/or the fine-grained pre-demud pulp refers to the concentration of mud and water therein.

The fine negatively charged materials produced during the grinding process affect the slurry concentration; desludging can improve the slurry viscosity problem, reduce the amount of reagents used, and facilitate subsequent flotation operations.

In actual operation, the coarse-grained minerals and/or fine-grained mineral powders obtained after classification are returned to the rod mill respectively, the pulp concentration is adjusted, and the time of the first crushing and/or the second crushing is set. After reaching the desliming particle size ratio, the pulp concentration is adjusted to perform desliming treatment. The time of the first crushing and/or the second crushing is 10 to 12 minutes.

In a specific embodiment of the present invention, the first desliming treatment and/or the second desliming treatment includes any one of equipment desliming, free sedimentation desliming and flotation desliming. The equipment desliming includes: spiral chute, shaking table, hydrocyclone and other equipment desliming.

In a specific embodiment of the present invention, the magnetic separation process includes: adjusting the concentration of the material to be magnetically separated to 10% to 15%, setting the magnetic field strength to 1.1 to 1.2 T, the feeding time to 50 to 80 s, the intermediate punching time to 30 to 60 s, and the fine punching time to 30 to 60 s.

For example, in different embodiments, in the magnetic separation process, the concentration of the material to be magnetically separated can be adjusted to 10%, 11%, 12%, 13%, 14%, 15% or a range consisting of any two; the magnetic field intensity can be 1.1T, 1.12T, 1.15T, 1.18T, 1.2T or a range consisting of any two; the feeding time can be 50s, 55s, 60s, 65s, 70s, 75s, 80s or a range consisting of any two; the intermediate punching time can be 30s, 35s, 40s, 45s, 50s, 55s, 60s or a range consisting of any two; the fine punching time can be 30s, 35s, 40s, 45s, 50s, 55s, 60s or a range consisting of any two.

In a specific embodiment of the present invention, the steps of the cleaning process include: coarsely crushing, cleaning and drying the low-grade clay-type lithium ore in sequence; further, the particle size of the coarsely crushed particles is 5 to 10 cm.

For example, in different embodiments, the coarsely crushed particles may have a size of 5 cm, 6 cm, 7 cm, 8 cm, 9 cm, 10 cm, or a range consisting of any two of them.

In actual operation, a jaw crusher can be used for the coarse crushing. The red mud attached to the surface of the lithium ore is removed by a cleaning device, and the cleaning device includes any one or more of a high-pressure water gun, a spiral sand washer, a wheel sand washer, a crushing sand washer, a crushing sand washer, and a bucket sand washer. The drying treatment method includes drying, which can be performed by a drying device such as a rotary single-drum dryer.

In a specific embodiment of the present invention, in the low-grade clay-type lithium ore, the grade of lithium oxide is less than 0.6%, and the aluminum-silicon ratio is less than 4. Furthermore, in the low-grade clay-type lithium ore, the aluminum-silicon ratio is ≤3, such as 2.95.

In a specific embodiment of the present invention, the grade of the lithium concentrate obtained by the ore dressing method is ≥1.40%, and the grade of the bauxite is ≥70%.

In a specific embodiment of the present invention, the aluminum-silicon ratio of the bauxite is greater than 5, and the grade of magnetic minerals is greater than or equal to 30%.

In a specific embodiment of the present invention, the recovery rate of the lithium concentrate is 35% to 42%.

For example, in different embodiments, the grade of the lithium concentrate obtained by the beneficiation method can be ≥1.40%, ≥1.41%, ≥1.42%, ≥1.43%, ≥1.44%, ≥1.45%, ≥1.46%, ≥1.47%, ≥1.48%, ≥1.49%, ≥1.5%, ≥1.51%, ≥1.52%, ≥1.53%, ≥1.54%, ≥1.55%, etc. The recovery rate of the lithium concentrate can be 35%, 35.5%, 36%, 36.5%, 37%, 37.5%, 38%, 38.5%, 39%, 39.5%, 40%, 40.5%, 41%, 41.5%, 42% or any two of the range. The grade of the bauxite may be ≥70%, ≥70.5%, ≥71%, ≥71.5%, ≥72%, etc., and the aluminum-silicon ratio of the bauxite may be >5, >5.1, >5.2, >5.3, >5.4, >5.5, etc. The grade of the magnetic mineral may be ≥30%, ≥31%, ≥32%, ≥33%, ≥34%, ≥35%, etc.

The low-grade clay-type lithium ore from a certain place used in the following embodiments is a test ore sample. The main mineral contents in the original ore include: 45% diaspore, 31% kaolinite, 7% mica, 2% magnetite (hematite), 2% anatase, and 3% lithium chlorite.

The original _ore contains 59.01% _Al2O3 , 20.02% _SiO2 , 2.53 _{% Fe2O3} , 0.38% _Li2O , and 2.95 aluminum-silicon ratio. The ore contains more diaspore, which is hard and mostly distributed in coarse-grained minerals. Kaolinite and lithium chlorite are embedded in fine-grained minerals, and a small part is embedded in diaspore.

Example 1

This embodiment provides a beneficiation method for low-grade clay-type lithium ore. The process flow diagram is shown in FIG1 , which specifically includes the following steps:

(1) Cleaning process

The low-grade clay-type lithium ore is pre-crushed to 5 cm, and the mineral is cleaned in a cleaning tank using a cleaning device. The cleaned mineral is dried by a drying device to obtain ore and red mud.

(2) Classification process

The coarsely crushed mineral dried in step (1) is sent to the grinding equipment, and the grinding time is set to 5 minutes, and the grading particle size is 0.32 mm. The ground mineral is sent to the grading equipment, and the sieve-surface material is the coarse-grained mineral, which is mainly composed of diaspore and some embedded aluminum silicate; the sieve-surface material is the fine-grained mineral, which is the aluminum silicate mineral.

(3) Desludging process

The coarse-grained minerals after classification in step (2) are returned to the rod mill, the pulp concentration is adjusted to 60%, the grinding time is set to 10 min, and the particle size is less than 0.074 mm, accounting for 80%, and the pulp is adjusted to a pulp concentration of 12%. Desliming is performed by free sedimentation to obtain coarse-grained pulp and first sludge;

The fine-grained minerals after classification in step (2) are returned to the rod mill, the pulp concentration is adjusted to 60%, the grinding time is set to 10 min, and the particle size is less than 0.074 mm, accounting for 80%. The pulp is adjusted to a pulp concentration of 12%, and desliming is carried out by free sedimentation to obtain fine-grained pulp and second slime.

(4) Flotation process

The coarse-grained ore pulp obtained in step (3) is diluted to a concentration of 10%, and a regulating agent of sodium carbonate 1000 g/t, a pH regulating agent of NaOH 800 g/t are added in sequence to adjust the ore pulp pH to 8.2, a depressant of sodium silicate 100 g/t, an activator of calcium chloride 100 g/t and a collector (the collector includes oleic acid and octyl hydroxamic acid in a mass ratio of 1:1) 800 g/t are added in sequence, and a reverse flotation dealuminization process of one coarse-one scavenging-one fine is carried out. The tailings obtained by the reverse flotation dealuminization process are combined with the fine-grained ore pulp obtained in step (3), and a desiliconizing regulating agent of sulfuric acid (mass fraction of 12%) 1500 g/t are added in sequence to adjust the ore pulp pH to 5, a desiliconizing activator of sodium chloride 150 g/t, and a desiliconizing collector of dodecylamine 500 g/t are added in sequence, and a reverse flotation desiliconization process of one coarse-one scavenging-one fine is carried out.

(5) Magnetic separation process

The concentration of the slurry obtained by the reverse flotation desiliconization process in step (4) is adjusted to 10%, the magnetic field strength is set to 1.1 T, the feeding time is 80 s, the intermediate flushing time is 40 s, and the fine flushing time is 60 s, to obtain lithium concentrate and magnetic minerals.

The product information obtained by the mineral processing method of this embodiment is shown in Table 1 below:

Table 1 Product information obtained in Example 1

Note: The sludge in the table represents the material after the first sludge and the second sludge are mixed. The same applies to the subsequent tables.

Among them, yield = the mass ratio of a certain product to the mass ratio of the selected raw ore; A/S is the ratio of alumina grade to silicon oxide grade; _Li2O recovery rate is the ratio of _Li2O content in a certain product to _Li2O content in the selected ore.

Example 2

This embodiment provides a beneficiation method for low-grade clay-type lithium ore. The process flow diagram is shown in FIG2 , which specifically includes the following steps:

(1) Cleaning process

The low-grade clay-type lithium ore is pre-crushed to 5 cm, and the mineral is cleaned in a cleaning tank using a cleaning device. The cleaned mineral is dried by a drying device to obtain ore and red mud.

(2) Classification process

The coarsely crushed mineral dried in step (1) is sent to the grinding equipment, and the grinding time is set to 5 minutes, and the grading particle size is 0.32 mm. The ground mineral is sent to the grading equipment, and the sieve-surface material is the coarse-grained mineral, which is mainly composed of diaspore and some embedded aluminum silicate; the sieve-surface material is the fine-grained mineral, which is the aluminum silicate mineral.

(3) Magnetic separation process

The coarse-grained mineral and the fine-grained mineral obtained in step (2) are subjected to magnetic separation processes respectively. Before the magnetic separation process, the coarse-grained mineral is adjusted to a coarse-grained slurry with a slurry concentration of 10%, and the fine-grained mineral is adjusted to a fine-grained slurry with a slurry concentration of 10%. A wet magnetic separator is used, the magnetic field strength is set to 1.2 T, the feeding time is 60 s, the intermediate punching time is 40 s, and the fine punching time is 60 s, to obtain demagnetized coarse-grained slurry and magnetic minerals, and demagnetized fine-grained slurry and magnetic minerals, respectively.

(4) Desludging process

The coarse-grained slurry after demagnetization in step (3) is returned to the rod mill, the slurry concentration is adjusted to 60%, the grinding time is set to 12 minutes, and the slurry is ground to a particle size less than 0.074 mm, accounting for 85%. The slurry is adjusted to a slurry concentration of 12%, and desludging is performed through a spiral chute to obtain a coarse-grained slurry and a first slurry;

The fine-grained slurry after demagnetization in step (3) is returned to the rod mill, and the slurry concentration is adjusted to 60%. The grinding time is set to 12 minutes, and the slurry is ground to a particle size less than 0.074 mm, accounting for 85%. The slurry is adjusted to a slurry concentration of 12%, and a fine-grained slurry and a second slurry are obtained through a spiral chute.

(5) Flotation process

The coarse-grained ore pulp obtained in step (4) is diluted to a concentration of 10%, and a regulating agent of sodium carbonate 1200 g/t, a pH regulating agent of NaOH 1000 g/t are added in sequence to adjust the ore pulp pH to 9.0, a depressant of carboxymethyl cellulose 100 g/t, an activator of ferric chloride 80 g/t and a collector (the collector includes octanoyl hydroxamic acid and oleic acid in a mass ratio of 1:1) 1000 g/t are added in sequence, and a reverse flotation dealuminization process of one coarse-one scavenging-one fine is carried out. The tailings obtained by the reverse flotation dealuminization process are combined with the fine-grained ore pulp obtained in step (4), and a desiliconizing regulating agent of sulfuric acid (mass fraction of 12%) 1500 g/t are added in sequence to adjust the ore pulp pH to 5, a desiliconizing activator of sodium fluoride 150 g/t, and a desiliconizing collector of hexadecyltrimethylammonium chloride 500 g/t are added in sequence, and a reverse flotation desiliconization process of one coarse-one scavenging-one fine is carried out.

The product information obtained by the mineral processing method of this embodiment is shown in Table 2 below:

Table 2 Product information obtained in Example 2

Among them, yield = the mass ratio of a certain product to the mass ratio of the selected raw ore; A/S is the ratio of alumina grade to silicon oxide grade; _Li2O recovery rate is the ratio of _Li2O content in a certain product to _Li2O content in the selected ore.

Example 3

This embodiment provides a beneficiation method for low-grade clay-type lithium ore. The process flow diagram is shown in FIG3 , which specifically includes the following steps:

(1) Cleaning process

The low-grade clay-type lithium ore is pre-crushed to 5 cm, and the mineral is cleaned in a cleaning tank using a cleaning device. The cleaned mineral is dried by a drying device to obtain ore and red mud.

(2) Classification process

The coarsely crushed mineral dried in step (1) is sent to the grinding equipment, and the grinding time is set to 5 minutes, and the grading particle size is 0.32 mm. The ground mineral is sent to the grading equipment, and the sieve-surface material is the coarse-grained mineral, which is mainly composed of diaspore and some embedded aluminum silicate; the sieve-surface material is the fine-grained mineral, which is the aluminum silicate mineral.

(3) Desludging process

The coarse-grained minerals after classification in step (2) are returned to the rod mill, the pulp concentration is adjusted to 60%, the grinding time is set to 12 minutes, and the particle size is less than 0.074 mm, accounting for 85%, and the pulp is adjusted to a pulp concentration of 12%. The coarse-grained pulp and the first sludge are obtained by shaking the slurry;

The fine-grained minerals classified in step (2) are returned to the rod mill, the pulp concentration is adjusted to 60%, the grinding time is set to 12 minutes, and the particle size is less than 0.074 mm, accounting for 85%. The pulp is adjusted to a pulp concentration of 12%, and a fine-grained pulp and a second sludge are obtained by shaking.

(4) Magnetic separation process

The coarse-grained slurry and the fine-grained slurry obtained in step (3) are subjected to magnetic separation processes respectively, the concentration of the slurry is adjusted to 10%, the magnetic field strength is set to 1.2T, the feeding time is 60s, the intermediate punching time is 40s, and the fine punching time is 60s, to obtain demagnetized coarse-grained slurry and magnetic minerals, and demagnetized fine-grained slurry and magnetic minerals, respectively.

(5) Flotation process

The demagnetized coarse-grained slurry obtained in step (4) is diluted to a concentration of 10%, and a regulating agent of sodium carbonate 1200 g/t, a pH regulating agent of NaOH 1200 g/t are added in sequence to adjust the slurry pH to 9.6, a depressant of dextrin 150 g/t, an activator of ferric chloride 80 g/t and a collector (the collector includes oleic acid and octyl hydroxamic acid in a mass ratio of 1:3) 1000 g/t are added in sequence, and a reverse flotation dealuminization process of one coarse, one scavenging and one fine is carried out. The tailings obtained by the reverse flotation dealuminization process are combined with the demagnetized fine-grained slurry obtained in step (4), and a desiliconizing regulating agent of sulfuric acid (mass fraction of 10%) 1500 g/t are added in sequence to adjust the slurry pH to 5, a desiliconizing activator of sodium fluoride 150 g/t, and a desiliconizing collector of hexadecyltrimethylammonium chloride 600 g/t are added in sequence, and a reverse flotation desiliconization process of one coarse, one scavenging and one fine is carried out.

The product information obtained by the mineral processing method of this embodiment is shown in Table 3 below:

Table 3 Product information obtained in Example 3

Among them, yield = the mass ratio of a certain product to the mass ratio of the selected raw ore; A/S is the ratio of alumina grade to silicon oxide grade; _Li2O recovery rate is the ratio of _Li2O content in a certain product to _Li2O content in the selected ore.

Example 4

This embodiment provides a beneficiation method for low-grade clay-type lithium ore, with reference to Example 2, the only difference being that in step (5), the type of collector in the reverse flotation dealumination process is different.

In step (5) of this embodiment, the collector in the reverse flotation dealumination process is oleic acid and octyl hydroxamic acid in a mass ratio of 2:1.

The product information obtained by the ore dressing method of Example 4 is shown in Table 4 below:

Table 4 Product information obtained in Example 4

Among them, yield = the mass ratio of a certain product to the mass ratio of the selected raw ore; A/S is the ratio of alumina grade to silicon oxide grade; _Li2O recovery rate is the ratio of _Li2O content in a certain product to _Li2O content in the selected ore.

It can be seen from Example 4 that when octyl hydroxamic acid and oleic acid are used in a mass ratio of <1:1, the collector has a strong collection capacity, resulting in an increase in the grade of bauxite, thereby resulting in a lower recovery rate of lithium concentrate.

Example 5

This embodiment provides a beneficiation method for low-grade clay-type lithium ore, with reference to Example 3, the only difference being that in step (5), the type of collector in the reverse flotation dealumination process is different.

In step (5) of this embodiment, the collector in the reverse flotation dealumination process is oleic acid and octyl hydroxamic acid in a mass ratio of 1:4.

The product information obtained by the ore dressing method of Example 5 is shown in Table 5 below:

Table 5 Product information obtained in Example 5

Among them, yield = the mass ratio of a certain product to the mass ratio of the selected raw ore; A/S is the ratio of alumina grade to silicon oxide grade; _Li2O recovery rate is the ratio of _Li2O content in a certain product to _Li2O content in the selected ore.

It can be seen from Example 5 that when octyl hydroxamic acid and oleic acid are used in a mass ratio of >3:1, the selectivity will be enhanced and the grade of lithium concentrate will be improved. However, due to the weak collection capacity of the collector, the yield will be low and the recovery rate of lithium concentrate will be low.

Example 6

This embodiment refers to the embodiment 1, and the only difference is that in step (4), the type of collector in the reverse flotation dealumination process is different.

The collector used in the reverse flotation dealumination process in this embodiment is octanoyl hydroxamic acid and octyl isohydroxamic acid in a mass ratio of 1:1.

The product information obtained by the ore dressing method of Example 6 is shown in Table 6 below:

Table 6 Product information obtained in Example 6

It can be seen from Example 6 that when only hydroxamic acid collectors are used, the lithium concentrate yield and recovery rate will decrease in the flotation system of the present invention.

Example 7

This embodiment refers to the embodiment 1, and the only difference is that in step (4), the type of collector in the reverse flotation dealumination process is different.

The collector used in the reverse flotation dealumination process in this embodiment is oleic acid and oxidized paraffin soap in a mass ratio of 1:1.

The product information obtained by the ore dressing method of Example 7 is shown in Table 7 below:

Table 7 Product information obtained in Example 7

It can be seen from Example 7 that when only carboxylic acid collectors are used, the grade of lithium concentrate will decrease in the flotation system of the present invention.

Example 8

Example 8 provides a method for beneficiating low-grade clay-type lithium ore, with reference to Example 1, except that in step (4), the type of collector in the reverse flotation dealumination process is different.

In step (4) of Example 8, the collector in the reverse flotation dealumination process is oleic acid.

The product information obtained by the ore dressing method of Example 8 is shown in Table 8 below:

Table 8 Product information obtained in Example 8

Among them, yield = the mass ratio of a certain product to the mass ratio of the selected raw ore; A/S is the ratio of alumina grade to silicon oxide grade; _Li2O recovery rate is the ratio of _Li2O content in a certain product to _Li2O content in the selected ore.

It can be seen from Example 8 that when oleic acid is used alone as a collector, it will lead to poor selectivity in the flotation system of the present invention, thereby resulting in a lower grade of lithium concentrate.

From the above content, it can be seen that the ore dressing method of the present invention removes various types of gangue minerals in the ore through a targeted process flow according to the difference in mineral properties and mineral contents of different particle sizes. First, the low-grade minerals are subjected to a cleaning process, and then the cleaned minerals are subjected to a classification process. The classified minerals are then subjected to a desliming process, and then the treated coarse-grained slurry is subjected to a reverse flotation dealumination process. The obtained tailings are combined with the fine-grained slurry for reverse flotation desiliconization process, etc., to obtain lithium concentrate and by-products such as bauxite, magnetite, and kaolin, wherein the bauxite meets the secondary standard of Bayer process for extracting alumina, the magnetite can be leached to prepare iron phosphate, and the kaolin can provide raw materials for refractory materials, cement, etc.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A method for beneficiating low-grade clay-type lithium ore, which is characterized by including the following steps: (a) Perform a cleaning process on low-grade clay-type lithium ore to obtain ore; (b) Perform a classification process on the ore to obtain coarse-grained minerals and fine-grained minerals; (c) subjecting the coarse-grained minerals to a first desliming process to obtain coarse-grained slurry; subjecting the fine-grained minerals to a second desliming process to obtain fine-grained slurry; (d) The coarse-grained ore slurry is subjected to reverse flotation and dealumination to obtain tailings and bauxite; the mixture obtained by mixing the tailings and the fine-grained ore slurry is subjected to reverse flotation and desiliconization to obtain Lithium concentrate. 2. The beneficiation method of low-grade clay-type lithium ore according to claim 1, characterized in that, in the step of reverse flotation dealumination, it also includes using a collector to collect the coarse-grained slurry. deal with; Preferably, the collector includes a hydroxamic acid collector and a carboxylic acid collector, and the mass ratio of the hydroxamic acid collector to the carboxylic acid collector is (1 to 3 ):1; Preferably, the usage amount of the collector is 800-1200g/t; Preferably, the hydroxamic acid collector includes at least one of octanoyl hydroxamic acid, octyl hydroxamic acid, benzohydroxamic acid, salicyl hydroxamic acid and hydroxamic acid; Preferably, the carboxylic acid collector includes at least one of oleic acid, sodium oleate and oxidized paraffin soap. 3. The beneficiation method of low-grade clay-type lithium ore according to claim 1, characterized in that the beneficiation method further includes using a magnetic separation process to obtain magnetic minerals; Preferably, the lithium-containing concentrate slurry after reverse flotation desilication is subjected to a magnetic separation process to obtain the lithium concentrate and the magnetic mineral; Alternatively, the coarse-grained minerals are subjected to a magnetic separation process to obtain the magnetically separated coarse-grained minerals and the magnetic minerals; the fine-grained minerals are subjected to a magnetic separation process to obtain the magnetically separated fine-grained minerals. and said magnetic minerals; Alternatively, the coarse-grained ore slurry is subjected to a magnetic separation process to obtain the magnetically separated coarse-grained ore slurry and the magnetic mineral; the fine-grained ore slurry is subjected to a magnetic separation process to obtain the magnetically separated fine-grained ore slurry. and said magnetic minerals. 4. The beneficiation method of low-grade clay-type lithium ore according to claim 2, characterized in that the step of reverse flotation dealumination includes: sequentially adding an adjusting agent and pH adjustment to the coarse-grained slurry. agents, inhibitors, activators and collectors; Preferably, the process steps of reverse flotation dealumination include one rough, one sweep and one fine, one rough, two sweeps and one fine, or one rough, two sweeps and two fines. 5. The beneficiation method of low-grade clay-type lithium ore according to claim 4, characterized in that the reverse flotation dealumination has at least one of the following characteristics: (1) The regulator includes sodium carbonate; (2) The dosage of the regulator is 1000~1500g/t; (3) The pH adjuster includes any one or more of sodium hydroxide, sodium carbonate and calcium hydroxide; (4) Add a pH adjuster to make the pH of the coarse-grained slurry reach 8 to 9.6; (5) The dosage of the pH adjuster is 800-1200g/t; (6) The inhibitor includes any one or more of sodium silicate, sodium hexametaphosphate, carboxymethyl cellulose, starch and dextrin; (7) The dosage of the inhibitor is 100~150g/t; (8) The activator includes any one or more of calcium chloride, aluminum chloride, ferric chloride and magnesium chloride; (9) The dosage of the activator is 80-200g/t. 6. The beneficiation method of low-grade clay-type lithium ore according to claim 1, characterized in that the step of reverse flotation desiliconization includes: adding a desiliconization regulator and desiliconization activation to the mixture in sequence. agent and desilicon collector; Preferably, the process steps of reverse flotation desiliconization include one rough sweep, one rough sweep and two sweeps, or one rough sweep and three sweeps. 7. The beneficiation method of low-grade clay-type lithium ore according to claim 6, characterized in that the reverse flotation desilication has at least one of the following characteristics: (1) The desilication regulator includes any one or more of sulfuric acid, acetic acid and hydrofluoric acid; (2) Add the desilicon regulator to make the pH of the mixture reach 5 to 7; (3) The dosage of the desilication regulator is 1500-2000g/t; (4) The desilicon activator includes any one or more of sodium chloride, sodium fluoride and sodium fluorosilicate; (5) The dosage of the desilication activator is 150-200g/t; (6) The desilicon collector includes any one of dodecylamine, hexadecylamine, octadecylamine, cetyltrimethylammonium chloride and cetyltrimethylamine bromide or variety; (7) The dosage of the desilicon collector is 500-800g/t. 8. The beneficiation method of low-grade clay-type lithium ore according to claim 1, characterized in that the classification process includes: crushing the ore and then dividing it into the coarse-grained minerals and the fine-grained minerals; Preferably, the particle size difference after crushing of the ore is 0.15 to 0.32 mm; Preferably, the ore crushing time is 5 to 8 minutes. 9. The beneficiation method of low-grade clay-type lithium ore according to claim 1, characterized in that the step of the first desliming process includes: first crushing the coarse-grained mineral to obtain a coarse-grained grade. After pre-deliming the slurry, perform the first desliming treatment to obtain the coarse-grained slurry; And/or, the steps of the second desliming process include: grinding the fine-grained mineral for a second time to obtain a fine-grained pre-deslimed slurry and then performing a second desliming treatment to obtain the fine-grained slurry. ; Preferably, the particle size of the coarse-grained pre-de-slimed slurry and/or the fine-grained pre-de-slimed slurry is less than 0.074mm; Preferably, the proportion of particle size less than 0.074mm is 80% to 85%; Preferably, the concentration of the coarse-grained pre-deslimed slurry and/or the fine-grained pre-deslimed slurry is 10% to 12%; Preferably, the method of the first desliming treatment and/or the second desliming treatment includes any one of equipment desliming, free settling desliming and flotation desliming; Preferably, the first grinding and/or second grinding time is 10 to 12 minutes. 10. The beneficiation method of low-grade clay-type lithium ore according to any one of claims 1 to 9, characterized in that the grade of the lithium concentrate obtained by the beneficiation method is ≥ 1.40%, and the bauxite is The grade of the ore is ≥70%; Preferably, the aluminum-silicon ratio of the bauxite is >5, and the grade of the magnetic mineral is >30%; Preferably, the recovery rate of the lithium concentrate is 35% to 42%.