A method and device for extracting lithium from clay-type lithium ore based on utilization of mineral resources

Abstract

The application discloses a method and device for extracting lithium from clay-type lithium ore based on mineral resource utilization, and the method comprises the following steps: grinding clay-type lithium raw ore into particle ore slurry, stirring and depositing to realize enrichment of the lithium ore, adding alum to the precipitate to leach lithium ions to obtain a first leaching liquor, adding limestone, gypsum and the first leaching liquor into the enriched lithium ore, performing aging treatment, and using a roasting process to prepare a mature blank, grinding the mature blank, adding deionized water to leach the lithium ions to obtain a second leaching liquor of lithium ions; the whole process does not use strong acid, has large output and low energy consumption, the impurity removal process of the obtained leaching liquor is simple, tailings are recycled and absorbed, and the comprehensive utilization rate of the lithium ore is high.

Description

Technical Field

[0001] This invention relates to the field of lithium extraction technology from lithium ore, and in particular to a method and apparatus for extracting lithium from clay-type lithium ore based on mineral resource utilization. Background Technology

[0002] Currently, lithium extraction technology is mainly determined by the form of lithium ore raw materials. Different raw material forms correspond to different extraction technologies. There is considerable research on lithium extraction processes from solid minerals like spodumene, with commonly used leaching methods including the sulfuric acid method, sulfate method, and chlorination roasting method. For liquid minerals such as salt lake brine, methods such as natural evaporation and concentration followed by precipitation and solvent extraction are mainly used. In recent years, with the discovery of new clay-type lithium resources, their corresponding extraction technologies have gradually become a focus of industry attention.

[0003] Clay-type lithium ore is commonly found in clay minerals such as montmorillonite. The lithium oxide content in clay-type lithium ore is typically no more than 1%, with lithium ions located within the mineral crystals. Direct lithium extraction using leaching or soaking methods is difficult. Chinese patent CN202010472603.7 discloses a lithium leaching method. The raw ore is crushed, ground into powder using a rod mill, mixed with concentrated sulfuric acid in a uniform ratio, heated and kept at a constant temperature, and then water is added and stirred for leaching. This technology uses high-temperature decomposition leaching with concentrated sulfuric acid, requiring high corrosion resistance in related equipment. The tailings cannot be directly utilized and require further treatment to remove strong acid. Chinese patent CN202010684178.8 discloses a lithium leaching method that mixes lithium-containing clay, calcium carbonate, sodium sulfate, and potassium sulfate to form spherical materials, which are then roasted, pulverized, and mixed with pure water for leaching. The disadvantage of this patented technology is that the leaching solution contains complex metal ions, which is not conducive to further lithium extraction, and the energy consumption cost is high. Chinese patent CN 202211534249.1 discloses a lithium leaching method, which involves crushing clay-type lithium ore, mixing it with an aqueous solution, stirring and allowing it to settle, then drying the upper slurry and conveying it to an electrostatic field for electrostatic separation to obtain concentrate powder. The concentrate powder is then mixed evenly with calcium sulfate and potassium sulfate and calcined to obtain a first powder. The first powder is then acid-washed with a sulfuric acid solution with a concentration of 50% to 90% and filtered to obtain a first filtrate. The final lithium extraction rate of the above method is only 60%, and the large-scale use of concentrated sulfuric acid also results in high slag treatment costs and is environmentally unfriendly.

[0004] From the perspective of existing technologies, lithium leaching rates can generally reach over 80% under various methods, but two key technological bottlenecks remain: first, the lack of a mineral processing and enrichment process, coupled with the large volume and high energy consumption of metallurgical roasting and leaching; and second, the generally low grade of clay-type lithium resources, which, if not comprehensively utilized and resource-based disposed of, will inevitably cause significant geological and environmental problems. With the rapid growth of global lithium resource consumption, lithium extraction from lithium clay ore will inevitably become a new source of lithium resources, and a simple, efficient, and industrially applicable extraction technology for lithium clay ore is urgently needed. Summary of the Invention

[0005] To address the problems existing in the prior art and achieve a simple, efficient, and industrially applicable method for extracting lithium from clay ore, this invention provides a method and apparatus for extracting lithium from clay-type lithium ore based on mineral resource utilization.

[0006] On one hand, the present invention provides a method for extracting lithium from clay-type lithium ore based on mineral resource utilization, comprising the following steps:

[0007] Step S1: Crush the clay-type lithium ore into powder, then add water and grind it into granular slurry.

[0008] In nature, montmorillonite has a layered structure composed of silicon-oxygen tetrahedra and aluminum-oxygen octahedra, with lithium oxide mainly existing between the layers. The ore is first mechanically activated through crushing and ball milling. During ball milling, the ore is continuously ground under impact, friction, and compression to form small, lithium-rich clay particles with a large specific surface area. Due to its fine structure, montmorillonite has a lower density than other clay-type lithium ores and exhibits water absorption and swelling characteristics. Therefore, when clay-type lithium ore powder is mixed with an aqueous solution, montmorillonite will swell due to water absorption and separate from other components in the powder. The grinding process with water disrupts the layered structure of montmorillonite, exposing the adsorbed lithium between the layers.

[0009] Through experiments, this invention has found that larger particle sizes, such as those greater than 0.5 mm, can prevent clumping during stirring, but this is not conducive to the full leaching of lithium. This invention reduces the particle size of clay-type lithium ore powder to below 300 μm. Smaller particle sizes correspond to larger specific surface areas, thereby ensuring the final lithium leaching rate.

[0010] Optionally, the particle size in the granular slurry is less than 200 μm.

[0011] Step S2: Transfer the granular slurry to a sedimentation tank, add water to the slurry and stir, and mix the raw ore and water thoroughly to form a suspension slurry according to a certain mass.

[0012] Optionally, the raw ore and water are thoroughly mixed in a mass ratio of 1:1.2 to 1:3.

[0013] The purpose of continuing to add water and stir the slurry is to ensure that as much montmorillonite as possible can absorb water, swell, and separate from other components; in a preferred embodiment, the mass ratio of clay lithium ore powder to added water is controlled at 1:2 throughout the process from crushing the clay lithium ore into powder to continuing to add water and stir to form a suspension.

[0014] Step S3: Continue stirring the suspension. After standing for a period of time, the suspension will separate into upper and lower layers.

[0015] Optionally, the stirring time of the suspension can be controlled to be 0.5 to 1.5 hours, and the settling time can be controlled to be 2 to 4 hours.

[0016] Step S4: Separate and transfer the upper lithium-rich slurry to the drying tank, and transfer the remaining precipitated slurry to the first leaching tank;

[0017] Step S5: Add alum to the first leaching tank at a mass ratio of 1:0.2 to the raw ore, and leach at a temperature of 50-70℃ to obtain a primary leachate and slag.

[0018] This invention uses alum as a leaching exchange agent. Due to the presence of aluminum and potassium ions in alum, and taking advantage of the fact that the adsorption capacity of montmorillonite interlayer cations for aluminum and potassium ions is much greater than that for lithium ions, lithium in the ore is exchanged into the primary leaching solution.

[0019] Optionally, the primary leaching is ultrasonic leaching, which allows lithium ions and sulfate ions in the precipitated slurry to fully combine and leach out. During the leaching process, the cavitation effect of ultrasound is utilized. Ultrasonic waves generate cavitation phenomena in the slurry. When the cavitation bubbles collapse, high temperatures above 5000K and high pressures of approximately 5×107Pa are generated in a very short time and in a very small space around the cavitation bubbles. The temperature change rate is as high as 109K / s, and strong shock waves and / or jets with speeds up to 400Km per hour are generated.

[0020] The cavitation effect of ultrasound can further promote the reaction between lithium ions and exchangers in lithium ore, while the jet also produces a strong stirring effect on the slurry. The combined effect of the two accelerates and promotes the efficient leaching of lithium from the ore.

[0021] Optionally, the leaching time for each leaching session shall not be less than 30 minutes. The slag produced by the leaching session can be dried and processed into industrial and agricultural products such as cement and fertilizer, or it can be directly used for backfilling of the mine.

[0022] Step S6: After drying the lithium-rich slurry in the drying tank, transfer it to the aging and greening chamber. Add limestone and gypsum in a mass ratio of 1:0.3:0.5, mix evenly, and then add concentrated primary leaching solution to make green greens.

[0023] Optionally, the exchanger for secondary leaching can be at least two of calcium carbonate, calcium sulfate, aluminum sulfate, and potassium sulfate; preferably, the exchanger for secondary leaching is a composite solution of calcium carbonate and calcium sulfate.

[0024] Optionally, after mixing evenly, the concentrated primary leachate is added to form a green body, which specifically includes two steps: aging treatment and pressing molding.

[0025] Optionally, during the aging process, the aging agent added is a concentrated primary leachate. The primary leachate is concentrated because the amount of water used in step S2 is relatively large, and the aging process cannot consume all of the primary leachate in step S5. Furthermore, the lithium ion concentration in the primary leachate is low. Therefore, the primary leachate needs to be concentrated, and the lithium ion concentration in the concentrated solution should be controlled to be greater than 0.05 g / L.

[0026] Optionally, the well-stirred mixture can be transferred to a storage silo for aging for 2 to 24 hours, allowing different materials in the mixture to mutually adsorb and penetrate the primary leachate, fully absorbing it and maintaining a consistent overall moisture content. This ensures that the pressed green body has a certain degree of viscosity and is internally uniform, which is beneficial for the uniform heating of the green body in the firing furnace, thus ensuring the quality of the finished green body.

[0027] Optionally, the humidity of the storage silo should be maintained at 70%–90%, and the temperature at 25℃–40℃.

[0028] Optionally, the pressed green body is honeycomb-shaped.

[0029] Step S7: Transfer the green blank to a firing furnace, heat it to 750-850 degrees Celsius, and fire it for 1.5-2 hours to produce a finished green blank;

[0030] Step S8: Grind the roasted molten blank into powder and transfer it to the second leaching tank. Add deionized water at a ratio of 1:0.4 to 1:1.2 by weight, and leach to separate the secondary leachate and filter residue.

[0031] Optionally, the roasted raw material is ground into powder, and the particle size of the powder is controlled to be no greater than 40μm.

[0032] Optionally, during the entire roasting process, an inert protective gas needs to be introduced into the roasting furnace, wherein the inert protective gas is one of nitrogen, argon or helium.

[0033] Optionally, a pressure leaching process is used for the secondary leaching, with the temperature controlled at 120-160℃ and the pressure controlled at 0.3-0.5MPa. The pressure leaching reaction lasts for no less than 30 minutes to promote the reaction between lithium ions and carbonate ions. The leaching time is 2 hours to obtain the secondary leachate.

[0034] Optionally, the filter residue after secondary leaching can be transferred back to the sedimentation tank and the operations of steps S2 to S5 can be performed to obtain the third leachate and slag. The third leachate is concentrated and used for subsequent green body aging treatment. The slag can be used to manufacture cement, fertilizer and other industrial and agricultural products, or it can be used to backfill the mine directly.

[0035] The lithium extraction method of this invention achieves a comprehensive lithium recovery rate between 85% and 89%.

[0036] On the other hand, the present invention provides an extraction device for lithium from clay-type lithium ore based on mineral resource utilization. The device includes: a first crushing ball mill, a sedimentation tank, a first leaching tank, a drying tank, and an aging and forming chamber, a roasting furnace, a second crushing ball mill, and a second leaching tank connected in sequence.

[0037] The first crushing ball mill is connected to the sedimentation tank, which is connected to the drying tank and the first leaching tank respectively. The drying tank and the first leaching tank are connected to the aging and blanking chamber respectively.

[0038] The first crushing ball mill crushes the clay-type lithium ore into powder, then adds water and grinds it into granular slurry; the sedimentation tank is equipped with a stirrer, the first leaching tank is equipped with an ultrasonic device, and the second leaching tank is a pressure cooking kettle.

[0039] Optionally, the second leaching tank is connected to the sedimentation tank, and the filter residue after secondary leaching is transferred to the sedimentation tank again.

[0040] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0041] 1. This invention significantly reduces the amount of sulfates and carbonates used in the process by first enriching the clay-type lithium ore with lithium before roasting and leaching. At the same time, it has a large output, low energy consumption, no dust, and the whole process is stable, easy to operate and control. Compared with acid leaching, the leaching solution obtained by this invention has a simpler impurity removal process.

[0042] 2. In the formulation of the technical solution of the present invention, lithium in lithium ore can be efficiently replaced, resulting in a high lithium conversion rate. The lithium ore roasted product reacts fully, and the soluble lithium content of the calcined product is high. Since strong acids or strong alkalis are not used as exchange agents in the process, the filter residue and slag are easy to handle and can be used to prepare industrial and agricultural products such as cement and fertilizers. This realizes the resource utilization of tailings, resulting in a high comprehensive utilization rate of lithium ore and a small environmental impact. Attached Figure Description

[0043] Figure 1 This is a flowchart illustrating a method for extracting lithium from clay-type lithium ore based on mineral resource utilization, according to an embodiment of the present invention.

[0044] Figure 2 This is a schematic diagram of the composition of a lithium extraction device for clay-type lithium ore based on mineral resource utilization, according to an embodiment of the present invention.

[0045] Reference numerals: 1-First crushing ball mill, 2-Sedimentation tank, 3-First leaching tank, 4-Drying tank, 5-Aging and blanking chamber, 6-Roasting furnace, 7-Second crushing ball mill, 8-Second leaching tank. Detailed Implementation

[0046] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following.

[0047] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of this invention, and not all of them.

[0048] Example 1:

[0049] like Figure 1 The diagram shows a flowchart of a method for extracting lithium from clay-type lithium ore based on mineral resource utilization, according to the present invention. 100 kg of montmorillonite clay-type lithium ore with a lithium content of 0.55% is selected, and lithium is extracted through the following steps:

[0050] Step S1: Crush the clay-type lithium ore into powder, add water and grind it into granular slurry; control the particle size of the granular slurry to be below 200μm.

[0051] Step S2: Transfer the granular slurry to a sedimentation tank, add water and stir, and mix the raw ore and water thoroughly to form a suspension slurry at a certain mass ratio of 1:2.

[0052] Step S3: Continue stirring the suspension. After standing for a period of time, the suspension will separate into upper and lower layers. Control the stirring time of the suspension to 1.5 hours and the standing time to 4 hours.

[0053] Step S4: Separate and transfer the upper lithium-rich slurry to the drying tank, and transfer the remaining precipitated slurry to the first leaching tank;

[0054] Step S5: Add alum to the first leaching tank at a mass ratio of 1:0.2 to the raw ore, and leach at a temperature of 50-70℃ to obtain a primary leaching solution and slag; the primary leaching is ultrasonic leaching, and the leaching time is 60 minutes.

[0055] Step S6: After drying the lithium-rich slurry in the drying tank, transfer it to the aging and blanking chamber. Add limestone and gypsum in a mass ratio of 1:0.3:0.5, mix evenly, and then add concentrated primary leaching solution to make green blanks. Transfer the evenly mixed material to the storage silo for aging for 12 hours. Maintain the humidity of the storage silo at 70% to 90% and the temperature at 25℃ to 40℃. The green blanks after pressing are honeycomb-shaped.

[0056] Step S7: Transfer the green blank to the baking furnace, heat it to 750 degrees and bake it for 2 hours to make the green blank.

[0057] Step S8: After grinding the calcined green body into powder, transfer it to the second leaching tank, add deionized water at a ratio of 1:1 by weight, and leach to separate the secondary leachate and filter residue; in this step, grind the calcined green body into powder, control the particle size of the powder to be no greater than 40μm, and introduce nitrogen gas for protection during the calcination process.

[0058] The secondary leaching process uses a pressure cooking leaching process, with the temperature controlled at 120℃, the pressure controlled at 0.5MPa, the pressure cooking reaction lasting for 30 minutes, and the leaching time for 2 hours to obtain the secondary leachate.

[0059] According to calculations, the overall lithium recovery rate of the lithium extraction method in this embodiment is 86.9%.

[0060] Example 2:

[0061] In this embodiment, 100 kg of montmorillonite clay-type lithium ore with a lithium content of 0.55% was selected. The overall lithium yield was calculated by changing the particle size of the ore, the roasting temperature, the proportion of deionized water in the secondary leaching, and the pressure cooking process temperature.

[0062] Clay-type lithium ore is crushed into powder, and the particle size in the granular slurry is controlled to be below 100μm. Water is added and the slurry is then ground into granular slurry.

[0063] The granular slurry is transferred to a sedimentation tank, where water is added and stirred. The raw ore and water are thoroughly mixed in a mass ratio of 1:2 to form a suspension.

[0064] Continue stirring the suspension for 1.5 hours, and after standing for 4 hours, the suspension will separate into upper and lower layers.

[0065] The upper lithium-rich slurry is separated and transferred to a drying tank, and the remaining precipitated slurry is transferred to the first leaching tank.

[0066] Alum was added to the first leaching tank at a mass ratio of 1:0.2 to the raw ore, and ultrasonic leaching was carried out at a temperature of 50-70℃ for 60 minutes to obtain a primary leachate and slag.

[0067] After drying the lithium-rich slurry in the drying tank, it is transferred to the aging and blanking chamber. Limestone and gypsum are added in a mass ratio of 1:0.3:0.5. After mixing evenly, concentrated primary leaching solution is added to form green blanks. The evenly mixed material is transferred to the storage silo for aging for 12 hours. The humidity of the storage silo is maintained at 70% to 90%, and the temperature is maintained at 25℃ to 40℃. The green blanks after pressing are honeycomb-shaped.

[0068] The green blanks are transferred to a baking furnace, heated to 850 degrees Celsius, and baked for 2 hours to produce mature blanks.

[0069] After the calcined molten blank is ground into powder, it is transferred to the second leaching tank and deionized water is added at a ratio of 1:1.2 by weight. The leaching process separates the secondary leachate and filter residue. In this step, the calcined molten blank is ground into powder, and the particle size of the powder is controlled to be no greater than 40μm. Nitrogen gas is introduced for protection during the calcination process.

[0070] The secondary leaching process uses a pressure cooking leaching process, with the temperature controlled at 160℃ and the pressure controlled at 0.5MPa. The pressure cooking reaction lasts for 30 minutes, and the leaching time is 2 hours to obtain the secondary leachate.

[0071] According to calculations, the overall lithium recovery rate of the lithium extraction method in this embodiment is 89.0%.

[0072] Example 3:

[0073] In this embodiment, 100 kg of montmorillonite clay-type lithium ore with a lithium content of 0.55% was selected. The aging steps were reduced, and the single-stage leaching process was changed to pressure leaching. The overall lithium yield was calculated.

[0074] Clay-type lithium ore is crushed into powder, and the particle size in the granular slurry is controlled to be below 200μm. Water is added and the ore is ground into granular slurry.

[0075] The granular slurry is transferred to a sedimentation tank, where water is added and stirred. The raw ore and water are thoroughly mixed in a mass ratio of 1:2 to form a suspension.

[0076] Continue stirring the suspension for 1.5 hours, and after standing for 4 hours, the suspension will separate into upper and lower layers.

[0077] The upper lithium-rich slurry is separated and transferred to a drying tank, and the remaining precipitated slurry is transferred to the first leaching tank.

[0078] Alum was added to the first leaching tank at a mass ratio of 1:0.2 to the raw ore, and leaching was carried out at a temperature of 50-70℃ for 60 minutes to obtain a primary leachate and slag.

[0079] After drying the lithium-rich slurry in the drying tank, limestone and gypsum are added in a mass ratio of 1:0.3:0.5. After mixing evenly, concentrated primary leaching solution is added to form green blocks.

[0080] The green blanks are transferred to a baking furnace, heated to 850 degrees Celsius, and baked for 2 hours to produce mature blanks.

[0081] After the calcined molten blank is ground into powder, it is transferred to the second leaching tank and deionized water is added at a ratio of 1:1.2 by weight. The leaching process separates the secondary leachate and filter residue. In this step, the calcined molten blank is ground into powder, and the particle size of the powder is controlled to be no greater than 40μm. Nitrogen gas is introduced for protection during the calcination process.

[0082] The secondary leaching process uses a pressure cooking leaching process, with the temperature controlled at 160℃ and the pressure controlled at 0.5MPa. The pressure cooking reaction lasts for 30 minutes, and the leaching time is 2 hours to obtain the secondary leachate.

[0083] According to calculations, the lithium extraction method in this embodiment achieves a comprehensive lithium recovery rate of 85.8%.

[0084] Example 4:

[0085] In this embodiment, 100 kg of montmorillonite clay-type lithium ore with a lithium content of 0.55% was selected. The aging steps were reduced, the stirring time was reduced, the pressure cooking reaction conditions were changed, and the leaching time was reduced. The overall lithium yield was calculated.

[0086] Clay-type lithium ore is crushed into powder, and the particle size in the granular slurry is controlled to be below 200μm. Water is added and the ore is ground into granular slurry.

[0087] The granular slurry is transferred to a sedimentation tank, where water is added and stirred. The raw ore and water are thoroughly mixed in a mass ratio of 1:2 to form a suspension.

[0088] Continue stirring the suspension for 0.5 hours, and after standing for 4 hours, the suspension will separate into upper and lower layers.

[0089] The upper lithium-rich slurry is separated and transferred to a drying tank, and the remaining precipitated slurry is transferred to the first leaching tank.

[0090] Alum was added to the first leaching tank at a mass ratio of 1:0.2 to the raw ore, and leaching was carried out at a temperature of 50-70℃ for 30 minutes to obtain a primary leachate and slag.

[0091] After drying the lithium-rich slurry in the drying tank, limestone and gypsum are added in a mass ratio of 1:0.3:0.5. After mixing evenly, concentrated primary leaching solution is added to form green blocks.

[0092] The green blanks are transferred to a baking furnace, heated to 850 degrees Celsius, and baked for 1 hour to produce the finished blanks.

[0093] After the calcined molten blank is ground into powder, it is transferred to the second leaching tank and deionized water is added at a ratio of 1:1.2 by weight. The leaching process separates the secondary leachate and filter residue. In this step, the calcined molten blank is ground into powder, and the particle size of the powder is controlled to be no greater than 40μm. Nitrogen gas is introduced for protection during the calcination process.

[0094] The secondary leaching process uses a pressure cooking leaching process, with the temperature controlled at 120℃, the pressure controlled at 0.3MPa, the pressure cooking reaction lasting for 15 minutes, and the leaching time for 1 hour to obtain the secondary leachate.

[0095] According to calculations, the overall lithium recovery rate of the lithium extraction method in this embodiment is 84.6%.

[0096] Example 5:

[0097] like Figure 2 The diagram shows a schematic of the composition of a lithium extraction device for clay-type lithium ore based on mineral resource utilization according to the present invention. The device includes: a first crushing ball mill 1, a sedimentation tank 2, a first leaching tank 3, a drying tank 4, and an aging and blanking chamber 5, a roasting furnace 6, a second crushing ball mill 7, and a second leaching tank 8 connected in sequence.

[0098] The first crushing ball mill 1 is connected to the sedimentation tank 2. The sedimentation tank 2 is connected to the drying tank 4 and the first leaching tank 3 respectively. The drying tank 4 and the first leaching tank 3 are connected to the aging and blanking chamber 5 respectively.

[0099] The first crushing ball mill 1 crushes the clay-type lithium ore into powder, then adds water and grinds it into granular slurry; the sedimentation tank 2 is equipped with a stirrer, the first leaching tank 3 is equipped with an ultrasonic device, and the second leaching tank 8 is a pressure cooking kettle.

[0100] It should be noted that the second leaching tank 8 can also be connected to the sedimentation tank 2, so that the filter residue after the second leaching can be transferred back to the sedimentation tank 2.

[0101] The apparatus of the present invention may also include a gas supply device that provides inert gas protection for the roasting furnace 6.

[0102] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for extracting lithium from clay-type lithium ore based on mineral resource utilization, characterized in that, The method includes the following steps: Step S1: After crushing the clay-type lithium ore into powder, add water and grind it into granular slurry. The particle size of the granular slurry is less than 200μm. Step S2: Transfer the granular slurry to a settling tank, add water to the slurry and stir, and mix the raw ore and water thoroughly to form a suspension slurry according to a certain mass ratio; mix the raw ore and water thoroughly according to a mass ratio of 1:1.2 to 1:

3. Step S3: Continue stirring the suspension. After standing for a period of time, the suspension will separate into upper and lower layers. Control the stirring time of the suspension to be 0.5 to 1.5 hours and the standing time to be 2 to 4 hours. Step S4: Separate and transfer the upper lithium-rich slurry to the drying tank, and transfer the remaining precipitated slurry to the first leaching tank; Step S5: Add alum to the first leaching tank at a mass ratio of 1:0.2 to the raw ore, and leach at a temperature of 50-70°C to obtain a primary leaching solution and slag; the primary leaching is ultrasonic leaching, which allows lithium ions and sulfate ions in the precipitated slurry to fully combine and leach out; Step S6: After drying the lithium-rich slurry in the drying tank, transfer it to the aging and greening chamber, add limestone and gypsum in a mass ratio of 1:0.3:0.5, mix evenly, and then add concentrated primary leaching solution to make green blocks; The process of mixing the materials thoroughly and then adding concentrated primary leachate to form green bodies specifically includes two steps: aging treatment and pressing. During the aging treatment, the added aging agent is concentrated primary leachate, and the lithium ion concentration in the concentrated primary leachate is greater than 0.05 g / L. The thoroughly mixed material is transferred to a storage silo for aging for 2–24 hours, maintaining a humidity of 70%–90% and a temperature of 25℃–40℃. The pressed green body has a honeycomb structure. Step S7: Transfer the green billet to a firing furnace, heat it to 750-850℃, and fire it for 1.5-2 hours to produce a finished billet; Step S8: Grind the calcined molten blank into powder, control the particle size of the powder to be no greater than 40μm, transfer it to the second leaching tank, add deionized water at a ratio of 1:0.4 to 1:1.2 by weight, and leach to separate the secondary leachate and filter residue. The secondary leaching uses a pressure leaching process, with the temperature controlled at 120-160℃ and the pressure controlled at 0.3-0.5MPa. The pressure leaching reaction lasts for no less than 30 minutes to promote the reaction between lithium ions and carbonate ions.

2. The method for extracting lithium from clay-type lithium ore based on mineral resource utilization according to claim 1, characterized in that, Throughout the roasting process, an inert protective gas must be introduced into the roasting furnace. The inert protective gas is one of nitrogen, argon, or helium.

3. A lithium extraction device for clay-type lithium ore based on mineral resource utilization, used to implement the method according to any one of claims 1-2, characterized in that, The apparatus includes: a first crushing ball mill, a sedimentation tank, a first leaching tank, a drying tank, and an aging and blanking chamber, a roasting furnace, a second crushing ball mill, and a second leaching tank connected in sequence; the first crushing ball mill is connected to the sedimentation tank, the sedimentation tank is connected to the drying tank and the first leaching tank respectively, and the drying tank and the first leaching tank are connected to the aging and blanking chamber respectively. The first crushing ball mill crushes the clay-type lithium ore into powder, then adds water and grinds it into granular slurry. The granular slurry is then transferred to a sedimentation tank. The upper lithium-rich slurry is separated and transferred to a drying tank, and the remaining precipitated slurry is transferred to a first leaching tank. The sedimentation tank is equipped with a stirrer, the first leaching tank is equipped with an ultrasonic device, and the second leaching tank is a pressure cooking kettle.

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