Beneficiation method for synchronously removing calcium and sulfur and enriching lithium from high-calcium and high-sulfur lithium-containing clay

Abstract

The invention belongs to the technical field of lithium-containing clay beneficiation, and particularly relates to a beneficiation method for synchronously removing calcium and sulfur and enriching lithium from high-calcium and high-sulfur lithium-containing clay, which comprises the following steps: S1, grinding the high-calcium and high-sulfur lithium-containing clay to obtain a monomer dissociation material; s2, adding water, an adjusting agent and a collecting agent into the monomer dissociation material for full size mixing, and then carrying out flotation calcium and sulfur removal operation to obtain calcium and sulfur tailings I and a lithium material; s3, an adjusting agent and a collecting agent are added into the lithium material for sufficient size mixing, then lithium concentration operation is conducted, and lithium enrichment and calcium-sulfur tailings II are obtained; the collecting agent is formed by mixing sodium oleate, amyl xanthate and ammonium dibutyl dithiophosphate. According to the method, the lithium-containing clay is treated by adopting an ore grinding-synchronous flotation short-flow process, about 60% of calcium-sulfur (iron) impurities can be removed, the lithium enriched product with the Li2O enrichment ratio larger than 2 and the Li2O recovery rate larger than 75% is obtained, and the popularization and application prospects are wide.

Description

Technical Field

[0001] The invention belongs to the technical field of lithium-containing clay beneficiation, and specifically relates to a beneficiation method for simultaneously decalcifying and sulfur-enriching lithium of high-calcium and high-sulfur lithium-containing clay. Background Art

[0002] As the global demand for clean energy continues to grow, lithium is increasingly used as an "energy metal" in the battery industry. However, traditional lithium resources such as spodumene, lepidolite and salt lake brine can no longer meet the growing market demand, especially considering that my country's external dependence on lithium resources is as high as 60%. Finding and developing new lithium resources is particularly important. As a potential new type of lithium resource, high-calcium and high-sulfur lithium-containing clay has the characteristics of large reserves and wide distribution, but its complex mineral composition and low lithium grade make its development and utilization face many challenges.

[0003] With the continuous deepening of the development and utilization of lithium resources, high-calcium and high-sulfur lithium-containing clay has gradually become one of the important sources of lithium ore. In view of the importance of high-calcium and high-sulfur lithium-containing clay and the limitations of existing technologies, it is of great significance to develop a mineral processing method that can simultaneously remove calcium and sulfur and effectively enrich lithium.

[0004] At present, the lithium extraction methods for high-calcium and high-sulfur lithium-containing clays are mainly concentrated on the roasting-leaching process. Although these processes have achieved lithium extraction to a certain extent, they have problems such as high energy consumption, long process, and high cost. In addition, due to the high content of calcium and sulfur in high-calcium and high-sulfur lithium-containing clays, traditional mineral processing methods are difficult to effectively remove calcium and sulfur simultaneously, which in turn affects the lithium enrichment effect. Therefore, when traditional mineral processing methods are used to treat high-calcium and high-sulfur lithium-containing clays, it is often difficult to achieve effective removal of calcium and sulfur and efficient enrichment of lithium. For example, invention patent 202310088368.7 discloses a method for beneficiating a lithium clay ore, which adopts a process of crushing-scrubbing enrichment-lithium selection classification-middling reprocessing, but the calcium content in the obtained comprehensive lithium concentrate product is still high (only reduced by about 50%); invention patents 202311106360.5 and 202310595591.0 disclose methods for beneficiation and enrichment of clay lithium ore, which mainly adopt gravity separation process, and both have the problem of incomplete removal of calcium and sulfur, so that the acid consumption of downstream sections is still high. The above methods also have the problem of only being able to process calcium or sulfur separately, and cannot achieve simultaneous removal, resulting in a lengthy process flow and low efficiency. In addition, with the increasingly stringent environmental protection requirements, the environmental pollution problems that may exist in traditional beneficiation methods also need to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to provide a method for simultaneously decalcifying and sulfurizing lithium-enriched high-calcium and high-sulfur lithium-containing clay in order to solve the technical problems in the prior art that it is difficult to simultaneously remove calcium and sulfur and to efficiently enrich lithium from high-calcium and high-sulfur lithium-containing clay.

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A method for simultaneously decalcifying and sulfurizing lithium-enriched high-calcium and high-sulfur lithium-containing clay, comprising the following steps:

[0008] S1: Grinding the high-calcium and high-sulfur lithium-containing clay ore to obtain a monomer dissociation material;

[0009] S2: adding water, a regulator and a collector to the monomer dissociation material to fully prepare the slurry, and then flotation decalcification and sulfur removal to obtain calcium sulfur tailings I and lithium materials;

[0010] S3: Continue to add the regulator and the collector to the lithium material to fully mix the slurry, and then perform lithium concentration operation to obtain lithium enriched product and calcium sulfur tailings II;

[0011] The collector is a mixture of sodium oleate, amyl xanthate and butyl ammonium xanthate in a mass ratio of 6:2:1.

[0012] In some embodiments, the high-calcium and high-sulfur lithium-containing clay has a CaO content of 15-25 wt%, a S content of 2-6 wt%, and a Li2O content of 0.25-0.4 wt%.

[0013] In some embodiments, the conditioning agent is sodium carbonate and / or sodium bicarbonate.

[0014] In some embodiments, in S1, the fineness of the monomer dissociation material is less than 0.045 mm, accounting for 85-97%.

[0015] In some embodiments, in S2, the concentration of the slurry after slurry adjustment is 28-33 wt%.

[0016] In some embodiments, in S2, the amount of the regulator is 600-1200 g / t of the high-calcium and high-sulfur lithium-containing clay ore, and the amount of the collector is 400-800 g / t of the high-calcium and high-sulfur lithium-containing clay ore.

[0017] In some embodiments, in S3, the amount of the regulator is 300-600 g / t of the high-calcium and high-sulfur lithium-containing clay ore, and the amount of the collector is 200-400 g / t of the high-calcium and high-sulfur lithium-containing clay ore.

[0018] It should be noted that the present invention realizes the enrichment of lithium minerals and the removal of impurities through flotation technology based on the differences in the physical and chemical properties of different minerals in high-calcium and high-sulfur lithium-containing clay. Specifically, the monomer dissociation of minerals is achieved by grinding, and the selective adsorption of flotation agents is utilized, combined with the optimization of flotation process, to achieve the effective enrichment of lithium minerals in high-calcium and high-sulfur lithium-containing clay and the simultaneous removal of calcium and sulfur impurities.

[0019] First, the raw ore is ground to crush the ore to a certain fineness so that the lithium minerals and impurity minerals such as calcium and sulfur can be fully separated. Monomer dissociation is the premise of flotation separation. Only when the mineral particles are independent of each other can they be effectively separated according to their physical and chemical properties.

[0020] In the flotation process, the hydrophilicity or hydrophobicity of the mineral surface is changed by adding specific flotation reagents (adjusting agents, collectors), thereby controlling the behavior of mineral particles at the gas-liquid interface. Among them, the adjusting agent is mainly used to adjust the pH value of the slurry and the electrical properties of the mineral surface to eliminate or reduce the electrostatic repulsion between mineral particles and promote the adsorption of mineral particles and collectors. The collector has the ability to selectively adsorb on the surface of the target mineral and make its surface hydrophobic, so that it floats to the surface of the slurry under the action of bubbles to form concentrate foam. The collector of the present application is a mixture of sodium oleate, amyl xanthate and butyl ammonium black medicine. The combined use of these three agents can further improve the recovery rate and grade of lithium minerals, as well as the effective removal of impurities. In S2, calcium and sulfur minerals preferentially combine with collectors and float to the surface of the slurry, thereby achieving preliminary decalcification and sulfur. In step S3, the lithium material obtained by rough selection is further refined by adding a regulator and a collector again to strengthen the adsorption effect between the lithium mineral and the collector, so that the lithium mineral is further enriched and floats to the surface of the slurry to form a lithium-enriched product.

[0021] The beneficial effects of the present invention are:

[0022] (1) The ore dressing method of the present invention has the advantages of short process, low energy consumption, high efficiency, good environmental protection, etc., and provides a new technical approach for the development and utilization of lithium resources;

[0023] (2) The present invention innovatively adopts a short process of grinding-simultaneous flotation to treat lithium-containing clay, which can remove about 60% of calcium and sulfur impurities and obtain a lithium-enriched product with a Li2O enrichment ratio greater than 2. It has excellent indicators and broad prospects for promotion and application;

[0024] (3) The present invention greatly reduces impurities such as calcium, sulfur, and iron in the materials entering the subsequent metallurgical lithium extraction process, significantly reduces metallurgical acid consumption and other costs, and helps to obtain economical metallurgical indicators of lithium-containing clay through a combined metallurgical process;

[0025] (4) The present invention innovatively utilizes the effective synergistic assembly of oxide ore collectors and sulfide ore collectors to enhance synchronous capture, thereby achieving a short-process synchronous removal of calcium-containing minerals and sulfur-containing minerals in lithium-containing clay, with significant results. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention provides a flow chart of a method for simultaneously decalcifying and sulfurizing lithium-enriched ore from high-calcium and high-sulfur lithium-containing clay. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0028] Example 1

[0029] 1. Ore characteristics:

[0030] A high-calcium and high-sulfur lithium-containing clay resource in a certain place has a Li2O content of 0.35%, a CaO content of 19.2%, a S content of 4.12%, and a TFe content of 2.33%. The carrier mineral of lithium is clay mineral (40.6%). The proportion of impurity minerals such as pyrite, calcite, dolomite and quartz in the coarse-grained grade is larger than that of clay minerals. Pyrite, pyrrhotite, carbonate minerals and quartz can be removed by mechanical impurity removal and tailing. The target mineral for mineral processing recovery is clay mineral. According to theoretical testing, the theoretical enrichment ratio of mineral processing concentrate is 2.4 times.

[0031] 2. The ore dressing method comprises the following steps:

[0032] S1: Grinding the high-calcium and high-sulfur lithium-containing clay ore to obtain a monomer dissociation material with a fineness of less than 0.045 mm and a content of 88%;

[0033] S2: adding water, a regulator and a collector to the monomer dissociation material to fully slurry the slurry, wherein the slurry concentration after slurrying is 29wt%, the amount of the regulator is 800g / t high-calcium and high-sulfur lithium-containing clay ore, and the amount of the collector is 600g / t high-calcium and high-sulfur lithium-containing clay ore, and then flotation decalcification and sulfurization operation is performed to obtain calcium sulfur tailings I and lithium materials;

[0034] S3: Continue to add the regulator and the collector to the lithium material to fully mix the slurry, the amount of the regulator is 400g / t high calcium and high sulfur type lithium-containing clay ore, the amount of the collector is 300g / t high calcium and high sulfur type lithium-containing clay ore, and then perform lithium concentration operation to obtain lithium enriched product and calcium sulfur tailings II;

[0035] The adjusting agent is sodium bicarbonate, and the collecting agent is a mixture of sodium oleate, amyl xanthate and butyl ammonium xanthate in a mass ratio of 6:2:1.

[0036] 3. The beneficiation results are shown in Table 1 below:

[0037] Table 1

[0038]

[0039] Example 2

[0040] 1. Ore characteristics:

[0041] A high-calcium and high-sulfur lithium-containing clay resource in a certain place has a Li2O content of 0.29%, a CaO content of 23.4%, a S content of 3.45%, and a TFe content of 2.12%. The carrier mineral of lithium is clay mineral (38.9%). The proportion of impurity minerals such as pyrite, calcite, dolomite and quartz in the coarse-grained grade is larger than that of clay minerals. Pyrite, pyrrhotite, carbonate minerals and quartz can be removed by mechanical impurity removal and tailing. The target mineral for mineral processing recovery is clay mineral. According to theoretical testing, the theoretical enrichment ratio of mineral processing concentrate is 2.5 times.

[0042] 2. The ore dressing method comprises the following steps:

[0043] S1: Grinding the high-calcium and high-sulfur lithium-containing clay ore to obtain a monomer dissociation material with a fineness of less than 0.045 mm and a content of 96.8%;

[0044] S2: adding water, a regulator and a collector to the monomer dissociation material to fully prepare the slurry, wherein the slurry concentration after preparation is 33wt%, the amount of the regulator is 1000g / t high-calcium and high-sulfur lithium-containing clay ore, and the amount of the collector is 750g / t high-calcium and high-sulfur lithium-containing clay ore, and then flotation decalcification and sulfurization operation is performed to obtain calcium sulfur tailings I and lithium materials;

[0045] S3: Continue to add the regulator and the collector to the lithium material to fully mix the slurry, the amount of the regulator is 500g / t high calcium and high sulfur type lithium-containing clay ore, the amount of the collector is 350g / t high calcium and high sulfur type lithium-containing clay ore, and then perform lithium concentration operation to obtain lithium enriched product and calcium sulfur tailings II;

[0046] The adjusting agent is sodium carbonate, and the collecting agent is a mixture of sodium oleate, amyl xanthate and butyl ammonium xanthate in a mass ratio of 6:2:1.

[0047] 3. The beneficiation results are shown in Table 2 below:

[0048] Table 2

[0049]

[0050]

[0051] Comparative Example 1

[0052] The ore characteristics are the same as those in Example 1. During the mineral processing, the collector is replaced with amyl xanthate, and the remaining steps and the dosage of the reagent remain unchanged. This comparative example is used to prove that the collector used in the present invention has a better technical effect. The mineral processing results are shown in Table 3 below.

[0053] Table 3

[0054]

[0055] Comparative Example 2

[0056] The ore characteristics are the same as those in Example 1. During the mineral processing, the collector is replaced with sodium oleate, and the other steps and the dosage of the reagent remain unchanged. This comparative example is used to prove that the collector used in the present invention has a better technical effect. The mineral processing results are shown in Table 4 below.

[0057] Table 4

[0058]

[0059] Comparative Example 3

[0060] The ore characteristics are the same as those in Example 1, and the ore dressing method comprises the following steps:

[0061] S1: Grinding the high-calcium and high-sulfur lithium-containing clay ore to obtain a monomer dissociation material with a fineness of less than 0.045 mm and a content of 88%;

[0062] S2: adding water, a regulator (sodium carbonate) and a first collector (amyl xanthate) to the monomer dissociation material to fully slurry the slurry, wherein the slurry concentration after slurrying is 29wt%, the amount of the regulator is 800g / t high-calcium and high-sulfur lithium-containing clay ore, and the amount of the first collector is 120g / t high-calcium and high-sulfur lithium-containing clay ore, and then flotation desulfurization operation is performed to obtain sulfur tailings and desulfurized materials;

[0063] S3. Add a second collector (sodium oleate) to the desulfurized material to fully slurry, the amount of the second collector is 480g / t high calcium and high sulfur type lithium-containing clay ore, and then perform flotation decalcification to obtain calcium tailings and lithium materials;

[0064] S4: Adding a regulator (sodium carbonate) and a third collector (a mixture of sodium oleate, grade pentyl xanthate, and butyl ammonium black medicine in a mass ratio of 6:2:1) to the lithium material to fully mix the slurry, the amount of the regulator is 400g / t high-calcium and high-sulfur lithium-containing clay ore, the amount of the collector is 300g / t high-calcium and high-sulfur lithium-containing clay ore, and then performing lithium concentration operations to obtain lithium enriched products and calcium sulfur tailings.

[0065] This comparative example is set with reference to patent CN115999758B, and desulfurization and decalcification are performed respectively by the first collector and the second collector, and the total amount of the first collector and the second collector is the same as the total amount of collectors used in the desulfurization calcium step in Example 1. The usage ratio of the first collector and the second collector is also set with reference to patent CN115999758B.

[0066] The beneficiation results are shown in Table 5 below:

[0067] Table 5

[0068]

[0069] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A method for simultaneously decalcifying and sulfur-enriching lithium in high-calcium and high-sulfur lithium-containing clay, characterized in that: The following steps are involved: S1: Grinding the high-calcium and high-sulfur lithium-containing clay ore to obtain a monomer dissociation material; S2: adding water, a regulator and a collector to the monomer dissociation material to fully prepare the slurry, and then flotation decalcification and sulfur removal to obtain calcium sulfur tailings I and lithium materials; S3: Continue to add the regulator and the collector to the lithium material to fully mix the slurry, and then perform lithium concentration operation to obtain lithium enriched product and calcium sulfur tailings II; The collector is a mixture of sodium oleate, amyl xanthate and butyl ammonium xanthate in a mass ratio of 6:2:

1.

2. The method for simultaneous decalcification and sulfur enrichment of lithium in a high-calcium and high-sulfur lithium-containing clay according to claim 1, characterized in that: The high-calcium and high-sulfur lithium-containing clay has a CaO content of 15-25wt%, a S content of 2-6wt%, and a Li2O content of 0.25-0.4wt%.

3. The method for simultaneous decalcification and sulfur enrichment of lithium in a high-calcium and high-sulfur lithium-containing clay according to claim 1, characterized in that: The adjusting agent is sodium carbonate and / or sodium bicarbonate.

4. The method for simultaneous decalcification and sulfur enrichment of lithium in a high-calcium and high-sulfur lithium-containing clay according to claim 1, characterized in that: In S1, the fineness of the monomer dissociation material is less than 0.045 mm and the content is 85-97%.

5. The method for simultaneous decalcification and sulfur enrichment of lithium in a high-calcium and high-sulfur lithium-containing clay according to claim 1, characterized in that: In S2, the concentration of the slurry after slurry adjustment is 28-33 wt%.

6. The method for simultaneous decalcification and sulfur enrichment of lithium in a high-calcium and high-sulfur lithium-containing clay according to claim 1, characterized in that: In S2, the amount of the adjusting agent is 600-1200 g / t of the high-calcium and high-sulfur lithium-containing clay ore, and the amount of the collecting agent is 400-800 g / t of the high-calcium and high-sulfur lithium-containing clay ore.

7. The method for simultaneous decalcification and sulfur enrichment of lithium from high-calcium and high-sulfur lithium-containing clay according to claim 1, characterized in that: In S3, the amount of the adjusting agent is 300-600 g / t of the high-calcium and high-sulfur lithium-containing clay ore, and the amount of the collecting agent is 200-400 g / t of the high-calcium and high-sulfur lithium-containing clay ore.

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