A method for beneficiating low-grade spodumene ore

Abstract

The present invention provides a kind of beneficiation method of low-grade spodumene ore, belongs to the field of mineral processing technology, and the method comprises the following steps: raw ore grinding, stirring and slurrying, flotation and other steps, wherein the stirring and slurrying operation uses YLH-01 as an adjusting agent, stirs under the original slurry pH condition, optimizes the rheological properties of the slurry, solves the problem that the fine mud covers the mineral surface and affects the ore sorting, and the flotation operation further improves the separation effect of spodumene and gangue minerals by the selective adsorption of collector PL2-01 on the spodumene surface, and realizes the efficient sorting of low-grade spodumene. The present invention is a new beneficiation method with good stability, good separation effect, high separation index and strong adaptability, which is suitable for promotion and application.

Description

Technical Field

[0001] The invention belongs to the technical field of ore dressing, and in particular relates to a ore dressing method for low-grade spodumene ore. Background Art

[0002] Lithium is an important basic raw material for the new energy industry, and spodumene is one of the important raw materials for lithium extraction. Spodumene usually coexists closely with minerals such as feldspar, and the similar chemical composition of the two makes the surface properties similar, making it difficult to separate by flotation under the traditional fatty acid collector system; in addition, feldspar is easily decomposed into clay minerals due to weathering and alteration, which is easy to crush and is very easy to mud during the crushing process. The fine mud formed has high surface energy and strong adsorption characteristics, causing the mineral particles in the slurry to be covered by fine mud, reducing the difference in surface properties and increasing the difficulty of flotation separation of spodumene and gangue.

[0003] In order to accelerate the realization of the strategic goal of "carbon neutrality and carbon peak", the country has vigorously developed the lithium battery new energy industry. The demand for lithium resources has increased year by year, and the efficient development of low-grade spodumene has become an important task to ensure the supply of lithium resources in the market. Low-grade spodumene ore usually has a higher feldspar content, a more serious degree of weathering, a finer spodumene embedded particle size, and a higher grinding fineness required, resulting in a higher content of fine mud in the slurry and a higher content of inevitable metal ions produced by the weathering process, which further aggravates the coverage of fine mud on the mineral surface. At the same time, the finer spodumene embedded particle size increases the difficulty of its flotation recovery.

[0004] In order to solve the problems of poor separation and recovery of low-grade spodumene ore, the traditional beneficiation method adds a large amount of sodium hydroxide and sodium carbonate for surface scrubbing, and adds a large amount of fatty acid collectors to enhance the collection effect of fine spodumene; however, this method is a typical "strong pulling and strong pressing" method. Although increasing the dosage of sodium hydroxide and sodium carbonate can reduce the coverage of fine mud on the mineral surface, it also significantly inhibits spodumene. At the same time, a large dose of collectors enhances the hydrophobicity of the surface of gangue minerals such as feldspar, and cannot effectively improve the separation indicators of low-grade spodumene.

[0005] Therefore, for low-grade and difficult-to-select spodumene ores, we carry out slurry fluid environment control and mineral processing agent system optimization to solve problems such as fine mud cover adsorption, difficulty in flotation separation of spodumene and gangue, and difficulty in recovering fine spodumene. We develop a set of mineral processing methods for low-grade spodumene ores with good stability, excellent separation effect, high selection index and strong adaptability, which is of great significance to improving the utilization level of low-grade spodumene mine resources and ensuring the healthy development of the lithium battery new energy industry. Summary of the invention

[0006] The purpose of the present invention is to provide a beneficiation method for low-grade spodumene ore with good stability, excellent separation effect, high separation index and strong adaptability, aiming to solve the problems existing in the existing spodumene beneficiation technology, such as fine mud adsorption covering the mineral surface, difficulty in flotation separation of spodumene and gangue, and difficulty in recovering fine spodumene.

[0007] The present invention is achieved by a method for beneficiating low-grade spodumene ore, comprising the following steps:

[0008] (1) grinding the raw spodumene ore;

[0009] (2) adding the adjusting agent YLH-01 to the slurry ground in step (1) and stirring to adjust the slurry;

[0010] (3) adding an activator, CaCl2, to the slurry after stirring and slurrying in step (2), and stirring;

[0011] (4) adding collector PL2-01 to the slurry stirred in step (3) and stirring;

[0012] (5) subjecting the slurry stirred in step (4) to rough separation of spodumene to obtain a rough spodumene concentrate and flotation tailings I;

[0013] (6) Sweeping the flotation tailings I obtained in step (5) twice to obtain flotation tailings and two scavenged tailings, and the two scavenged tailings are returned to the previous operation in sequence; wherein the process conditions for scavenging the flotation tailings I twice are: adding 30-100 g / t of CaCl2 and 100-500 g / t of collector PL2-01 to scavenging I, and adding 50-300 g / t of collector PL2-01 to scavenging II;

[0014] (7) The spodumene rough concentrate obtained in step (5) is beneficiated twice to obtain a spodumene concentrate and two beneficiated intermediates, and the two beneficiated intermediates are returned to the previous operation in sequence; wherein the process conditions for beneficiating the spodumene rough concentrate twice are: adding 300-600 g / t of adjusting agent YLH-01 in beneficiation I and adding 100-500 g / t of adjusting agent YLH-01 in beneficiation II.

[0015] Preferably, in step (1), the grinding fineness is -0.074 mm and the content is 70-85%, and the mass concentration of the slurry obtained after grinding is 28-40%;

[0016] Preferably, in step (2), the amount of YLH-01 is 800-2000 g / t, the stirring and slurrying time is 15-35 min, and the shear rate of stirring and slurrying is 50-250 s -1 .

[0017] Preferably, in step (3), the amount of CaCl2 is 50 to 300 g / t, and the stirring time is 3 to 5 min.

[0018] Preferably, in step (4), the amount of collector PL2-01 is 800-1800 g / t, and the stirring time is 3-5 min.

[0019] Preferably, the adjusting agent YLH-01 is obtained by mixing nitrilotri(methylenephosphonic acid sodium salt), poly(sodium 4-styrene sulfonate) and carboxymethyl cellulose in a mass ratio of 5:3:2 and stirring the mixture evenly.

[0020] Preferably, the collector PL2-01 is obtained by mixing styrenephosphonic acid, 3-triethoxysilylpropyltrimethylammonium chloride and cotton oil soap in a mass ratio of 6:1:3 and stirring them evenly.

[0021] The present invention overcomes the deficiencies of the prior art and provides a method for beneficiating low-grade spodumene ore, which has the following technical features:

[0022] (1) The present invention optimizes the slurry fluid environment based on the slurry rheology control angle, adopts YLH-01 as a regulator, and solves the cover adsorption of fine mud on the surface of the mine by adjusting the yield stress and apparent viscosity of the slurry. The principle is that under a specific shear stirring intensity, the nitrilotri (methylenephosphonic acid sodium salt) rich in phosphate groups in the reagent is fully adsorbed on the mineral surface, changing the mineral surface potential, increasing the repulsion between fine mud and mineral particles, and desorbing fine mud from the mineral surface; using the synergistic effect of poly (sodium 4-styrene sulfonate) and phosphonic acid groups to further increase the repulsion between particles; using carboxyl groups rich in carboxyl methyl cellulose to complex the inevitable metal ions in the slurry, avoiding the re-adsorption of fine mud after the metal ions are adsorbed on the mineral surface. The shear stirring intensity used in the present invention is obtained through a large number of flotation tests and slurry rheology tests, and the regulator YLH-01 used is developed through a large number of reagent adsorption tests and flotation tests. Its shear stirring intensity, reagent composition and proportion are not disclosed and not easy to be thought of in the field of this technology.

[0023] (2) The present invention uses PL2-01 as a collector to further solve the problems of difficulty in flotation separation of spodumene and gangue minerals such as feldspar, and difficulty in recovering fine spodumene. The specific mode of action is to utilize the characteristics that the O solid-philic atom in the phosphate group of styrenephosphonic acid is more active and has a stronger complexing ability than the solid-philic atom in the carboxyl group of the fatty acid collector, and the adsorption intensity on the surface of spodumene is higher than that of gangue minerals such as feldspar, thereby achieving selective adsorption on the surface of spodumene and improving the selectivity of the collector; utilizing the molecular association between the cationic collector 3-triethoxysilylpropyltrimethylammonium chloride and the phosphoric acid of the anionic collector styrenephosphonic acid to form a multilayer adsorption on the surface of spodumene, further enhancing the hydrophobicity of the spodumene surface and improving the collection ability of the agent; utilizing the carboxylic acid group of cotton oil soap to strengthen the collection effect of spodumene, and utilizing its rich foam characteristics to strengthen the foaming property of the agent; the collector PL2-01 used in the present invention is developed through a large number of agent adsorption tests and flotation tests, and its agent components and proportions are not disclosed and are not easy to be thought of in the field of this technology.

[0024] Compared with the prior art, the advantages of the present invention are:

[0025] ① The present invention solves the problem of poor separation of spodumene and gangue caused by fine mud covering the mineral surface, thereby improving the quality of spodumene concentrate. At the same time, it avoids the problem of deep inhibition of spodumene caused by adding a large amount of NaOH and Na2CO3 in the traditional mineral processing process, thereby improving the recovery effect of spodumene.

[0026] ② The present invention solves the problems of poor separation effect and difficulty in recovering fine-grained spodumene caused by low capture capacity and poor selectivity of traditional reagent systems, and improves the sorting efficiency of spodumene. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The effect of the shear stirring slurry adjustment agent YLH-01 on the rheological properties of slurries with different fine-grained feldspar (-19μm) contents is shown in Figure (a), where the yield stress of the slurry changes under different fine-grained feldspar (-19μm) contents, and Figure (b) changes the apparent viscosity of the slurry under different fine-grained feldspar (-19μm) contents. The results show that with the increase of fine-grained feldspar content, the rheological properties of the slurry significantly deteriorate, and its yield stress and apparent viscosity are greatly increased; using YLH-01 as an adjustment agent, the shear stirring slurry adjustment method can effectively optimize the rheological properties of the slurry, and its yield stress and apparent viscosity are significantly reduced, and the effect is better with the increase of the amount of adjustment agent.

[0028] Figure 2The effect of the adjusting agent YLH-01 of the present invention on the interaction between spodumene and feldspar particles. The results show that when there is no adjusting agent, when the distance between the two mineral particles is greater than 31nm, there is a certain attraction. After adding the adjusting agent YLH-01, the repulsion between the two mineral particles is significantly increased, and the attraction between the particles is significantly eliminated, which is conducive to the desorption of fine mud from the mineral surface.

[0029] Figure 3 The figure shows the desorption effect of fine mud on the surface of spodumene mineral under different action times of the shear stirring slurry adjustment agent YLH-01 of the present invention. Figure (a) is a scanning electron microscope image of the spodumene surface after 5 minutes of shear stirring, and Figure (b) is a scanning electron microscope image of the spodumene surface after 30 minutes of shear stirring.

[0030] Figure 4 It is a flow chart of the steps of the beneficiation method of low-grade spodumene ore of the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] Example 1

[0033] 500g of nitrilotri(methylenephosphonic acid sodium salt), 300g of poly(sodium 4-styrene sulfonate) and 200g of carboxymethyl cellulose were mixed as raw materials. The mixing process was carried out at normal temperature and pressure. A beaker was used as a container and a linkage stirrer was used for stirring (stirring time was 30min). No other auxiliary facilities and additives were required. After mixing evenly, the adjusting agent YLH-01 was obtained.

[0034] 600g of styrenephosphonic acid, 100g of 3-triethoxysilylpropyltrimethylammonium chloride and 300g of cotton oil soap were mixed and prepared. The mixing process was carried out in a constant temperature water bath at 60°C and normal pressure. A beaker was used as a container and a linkage stirrer was used for stirring (stirring time was 30min). No other auxiliary facilities and additives were required. After mixing evenly, the collector PL2-01 was obtained.

[0035] Example 2

[0036] The selected ore is a granite pegmatite spodumene ore, the original ore contains 0.62% Li2O, the main mineral components of the ore are spodumene, rotten spodumene, albite, plagioclase, quartz, muscovite, biotite, kaolinite, apatite, beryl, illite, spodumene is fine-grained, and the ore is highly weathered and altered. The spodumene concentrate obtained by the traditional spodumene flotation process contains 4.82% Li2O and a recovery rate of 70.25%.

[0037] The spodumene shearing agglomeration flotation recovery ore dressing method of the present invention is used to sort the spodumene, and the sorting steps are as follows:

[0038] (1) taking and grinding the spodumene ore, wherein the grinding fineness is -0.074 mm and the content is 81%, and the mass concentration of the spodumene ore obtained after grinding is 34%;

[0039] (2) Adding 1300 g / t of the adjusting agent YLH-01 to the slurry ground in step (1), stirring and slurrying for 28 min;

[0040] (3) adding 150 g / t of activator CaCl2 to the slurry after stirring and slurrying in step (2), and stirring for 3 min;

[0041] (4) adding 1400 g / t of collector PL2-01 to the slurry stirred in step (3) and stirring for 3 min;

[0042] (5) subjecting the slurry stirred in step (4) to rough separation of spodumene to obtain a rough spodumene concentrate and flotation tailings I;

[0043] (6) The flotation tailings I obtained in step (5) are scavenged twice to obtain flotation tailings and two scavenged tailings, and the two scavenged tailings are returned to the previous operation in sequence; wherein the process conditions for scavenging the flotation tailings I twice are: adding 50 g / t of CaCl2 and 200 g / t of collector PL2-01 to scavenging I, and adding 150 g / t of collector PL2-01 to scavenging II;

[0044] (7) The spodumene rough concentrate obtained in step (5) is beneficiated twice to obtain a spodumene concentrate and two beneficiated intermediates, and the two beneficiated intermediates are returned to the previous operation in sequence; wherein the process conditions for beneficiating the spodumene rough concentrate twice are: adding 500 g / t of adjusting agent YLH-01 in beneficiation I and adding 300 g / t of adjusting agent YLH-01 in beneficiation II;

[0045] The spodumene concentrate obtained in this embodiment contains 5.66% Li2O and has a recovery rate of 78.24%.

[0046] Example 3

[0047] The selected ore contains 0.83% Li2O. The main minerals of the ore are spodumene, potassium feldspar, plagioclase, petalite, common pyroxene, quartz, biotite, kaolinite, chlorite, montmorillonite, topaz, fluorite, garnet, etc. The ore is mainly produced in blocky structure. Spodumene and feldspar in the ore are distributed in aggregates and have fine embedded grains. Albite and sericite are severely weathered and altered. The edges of the ore are replaced by clay minerals, and the ore is highly muddy. The spodumene concentrate obtained by traditional spodumene flotation process contains 5.24% Li2O and the recovery rate is 66.18%.

[0048] The spodumene shearing agglomeration flotation recovery ore dressing method of the present invention is used to sort the spodumene, and the sorting steps are as follows:

[0049] (1) taking and grinding the spodumene ore, wherein the grinding fineness is -0.074 mm and the content is 77%, and the mass concentration of the spodumene ore obtained after grinding is 31%;

[0050] (2) Adding 1600 g / t of the adjusting agent YLH-01 to the slurry ground in step (1), stirring and slurrying for 32 min;

[0051] (3) adding 200 g / t of activator CaCl2 to the slurry after stirring and slurrying in step (2), and stirring for 3 min;

[0052] (4) Adding 1300 g / t of collector PL2-01 to the slurry stirred in step (3) and stirring for 3 min;

[0053] (5) subjecting the slurry stirred in step (4) to rough separation of spodumene to obtain a rough spodumene concentrate and flotation tailings I;

[0054] (6) Sweeping the flotation tailings I obtained in step (5) twice to obtain flotation tailings and two scavenged tailings, and the two scavenged tailings are returned to the previous operation in sequence; wherein the process conditions for scavenging the flotation tailings I twice are: adding 50 g / t of CaCl2 and 300 g / t of collector PL2-01 to scavenging I, and adding 200 g / t of collector PL2-01 to scavenging II;

[0055] (7) The spodumene rough concentrate obtained in step (5) is beneficiated twice to obtain a spodumene concentrate and two beneficiated intermediates, and the two beneficiated intermediates are returned to the previous operation in sequence; wherein the process conditions for beneficiating the spodumene rough concentrate twice are: adding 400 g / t of adjusting agent YLH-01 in beneficiation I and adding 300 g / t of adjusting agent YLH-01 in beneficiation II;

[0056] The spodumene concentrate obtained in this embodiment contains 5.89% Li2O and has a recovery rate of 74.33%.

[0057] Example 4

[0058] The selected ore contains 0.74% Li2O. The main minerals of the ore are spodumene, spodumene, potassium feldspar, plagioclase, common pyroxene, quartz, muscovite, sericite, kaolinite, chlorite, topaz, fluorite, etc. The spodumene and feldspar in the ore are distributed in aggregates with fine embedded particles. The ore is highly weathered and muddy. There are a lot of yellow clay minerals, which are mainly weathering products of primary ore bodies. The spodumene concentrate obtained by traditional spodumene flotation process contains 4.69% Li2O and the recovery rate is 75.27%.

[0059] The spodumene shearing agglomeration flotation recovery ore dressing method of the present invention is used to sort the spodumene, and the sorting steps are as follows:

[0060] (1) taking and grinding the spodumene ore, wherein the grinding fineness is -0.074 mm and the content is 75%, and the mass concentration of the spodumene ore obtained after grinding is 32%;

[0061] (2) Adding 1500 g / t of the adjusting agent YLH-01 to the slurry ground in step (1), stirring and slurrying for 30 min;

[0062] (3) adding activator CaCl2 180 g / t to the slurry after stirring and slurrying in step (2), and stirring for 3 min;

[0063] (4) Adding 1200 g / t of collector PL2-01 to the slurry stirred in step (3) and stirring for 3 min;

[0064] (5) subjecting the slurry stirred in step (4) to rough separation of spodumene to obtain a rough spodumene concentrate and flotation tailings I;

[0065] (6) Sweeping the flotation tailings I obtained in step (5) twice to obtain flotation tailings and two scavenged tailings, and the two scavenged tailings are returned to the previous operation in sequence; wherein the process conditions for scavenging the flotation tailings I twice are: adding 60 g / t of CaCl2 and 200 g / t of collector PL2-01 to scavenging I, and adding 100 g / t of collector PL2-01 to scavenging II;

[0066] (7) The spodumene rough concentrate obtained in step (5) is beneficiated twice to obtain a spodumene concentrate and two beneficiated intermediates, and the two beneficiated intermediates are returned to the previous operation in sequence; wherein the process conditions for beneficiating the spodumene rough concentrate twice are: adding 400 g / t of adjusting agent YLH-01 in beneficiation I and adding 200 g / t of adjusting agent YLH-01 in beneficiation II;

[0067] The spodumene concentrate obtained in this embodiment contains 5.75% Li2O and has a recovery rate of 82.58%.

[0068] The present invention provides a method for beneficiating low-grade spodumene ore, belonging to the field of mineral processing technology. The method comprises the following steps: grinding of raw ore, stirring and slurrying, flotation and the like, wherein the stirring and slurrying operation uses YLH-01 as an adjusting agent, stirs under the pH condition of the raw slurry, optimizes the rheological properties of the slurry, solves the problem that the fine mud covers the mineral surface and affects the ore sorting, and the flotation operation further improves the separation effect of spodumene and gangue minerals through the selective adsorption of the collector PL2-01 on the surface of spodumene, and realizes the efficient sorting of low-grade spodumene. The present invention is a new method for beneficiation with good stability, good separation effect, high separation index and strong adaptability, and is suitable for promotion and application.

[0069] In the above embodiments, the contents not described in detail in this specification are known prior art to professionals in the field. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for beneficiating low-grade spodumene ore, characterized in that: The following steps are involved: (1) Grinding the spodumene ore; (2) Adding the adjusting agent YLH-01 to the slurry after grinding in step (1) and stirring to adjust the slurry; (3) adding an activator, CaCl2, to the slurry after stirring and slurrying in step (2) and stirring; (4) adding the collector PL2-01 to the slurry after stirring in step (3) and stirring; (5) subjecting the slurry stirred in step (4) to rough separation of spodumene to obtain a rough spodumene concentrate and flotation tailings I; (6) scavenging the flotation tailings I obtained in step (5) twice to obtain flotation tailings and two scavenged tailings, and the two scavenged tailings are returned to the previous operation in sequence; The process conditions for the two scavenging of flotation tailings I are as follows: adding CaCl2 30-100 g / t and collector PL2-01 100-500 g / t in scavenging I, and adding collector PL2-01 50-300 g / t in scavenging II; (7) The spodumene coarse concentrate obtained in step (5) is beneficiated twice to obtain a spodumene concentrate and two beneficiated intermediates, and the two beneficiated intermediates are returned to the previous operation in sequence; The process conditions for the two times of concentrating spodumene rough concentrate are as follows: adding adjusting agent YLH-01 300-600g / t in concentrating I and adding adjusting agent YLH-01 100-500g / t in concentrating II; The adjusting agent YLH-01 is obtained by mixing nitrilotri(methylenephosphonic acid sodium salt), poly(sodium 4-styrene sulfonate) and carboxymethyl cellulose in a mass ratio of 5:3:2 and stirring evenly; The collector PL2-01 is obtained by mixing styrenephosphonic acid, 3-triethoxysilylpropyltrimethylammonium chloride and cotton oil soap in a mass ratio of 6:1:3 and stirring evenly.

2. A method for beneficiating a low-grade spodumene ore as claimed in claim 1, characterized in that: In step (1), the fineness of the ground spodumene ore is -0.074 mm and the content is 70-85%. The mass concentration of the spodumene ore obtained after grinding is 28-40%.

3. A method for beneficiating a low-grade spodumene ore as claimed in claim 1, characterized in that: In step (2), the amount of YLH-01 is 800-2000 g / t, the stirring and slurrying time is 15-35 min, and the shear rate of stirring and slurrying is 50-250 S -1 .

4. A method for beneficiating low-grade spodumene ore as claimed in claim 1, characterized in that: In step (3), the amount of CaCl2 used is 50 to 300 g / t, and the stirring time is 3 to 5 min.

5. A method for beneficiating low-grade spodumene ore as claimed in claim 1, characterized in that: In step (4), the amount of collector PL2-01 is 800 to 1800 g / t, and the stirring time is 3 to 5 min.

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