A method for recovering lithium element from aluminum electrolysis overhaul slag

Abstract

The application provides a method for recovering lithium elements from aluminum electrolysis overhaul slag, and relates to the technical field of lithium recovery.The method for recovering lithium elements from aluminum electrolysis overhaul slag comprises the following steps: step S1, raw material pretreatment; step S2, fluorine fixation treatment, the dry overhaul slag, calcium oxide and deionized water are uniformly mixed according to a mixing ratio, and then are placed into a muffle furnace for calcination treatment, so that the fluorine in the overhaul slag reacts with the calcium oxide; step S3, first-stage reaction treatment; step S4, second-stage reaction treatment; step S5, third-stage reaction treatment; and step S6, lithium extraction treatment.The method can efficiently recover metal elements in the aluminum electrolysis overhaul slag, the metal elements include lithium elements and aluminum elements, and the fluorine elements can be fixed in the process of recovering the lithium elements, so that environmental pollution is reduced; and high-purity lithium carbonate and aluminum oxide products are prepared, metal recovery and comprehensive utilization of waste resources are realized, and the maximization of economic benefits is recovered and utilized.

Description

Technical Field

[0001] This invention relates to the field of lithium recovery technology, and in particular to a method for recovering lithium from aluminum electrolysis overhaul slag. Background Technology

[0002] The aluminum electrolysis production process generates a large amount of overhaul slag. This slag has a complex composition, containing abundant elements such as lithium, aluminum, and fluorine. Traditionally, some companies have chosen to directly stockpile or landfill this slag. However, the acidic soluble fluorides contained in the slag can leach into the natural environment, causing serious pollution to the soil and groundwater. Furthermore, both storage and landfilling require substantial investment and operational management costs, and pose long-term potential pollution risks.

[0003] With the widespread application of lithium in batteries and other fields, the demand for lithium resources is increasing. The lithium element contained in aluminum electrolysis overhaul slag has significant recycling value. Effective recycling and utilization of this lithium could not only alleviate the lithium resource shortage but also achieve resource recycling and reduce production costs. Further research is needed to effectively improve the recycling rate of resources in overhaul slag.

[0004] Therefore, it is necessary to provide a method for recovering lithium from aluminum electrolysis overhaul slag to solve the above-mentioned technical problems. Summary of the Invention

[0005] This invention provides a method for recovering lithium from aluminum electrolysis overhaul slag, which solves the problem in related technologies that requires further research on how to effectively improve the resource recovery rate in overhaul slag.

[0006] To solve the above-mentioned technical problems, the present invention provides a method for recovering lithium from aluminum electrolysis overhaul slag, comprising the following steps:

[0007] Step S1, raw material pretreatment: the aluminum electrolysis overhaul slag is ground and then dried for later use.

[0008] Step S2, Fluorine fixation treatment: The dried overhaul residue, calcium oxide and deionized water are mixed evenly according to the mixing ratio, and then placed in a muffle furnace for calcination treatment, so that the fluorine in the overhaul residue reacts with the calcium oxide to generate calcium fluoride.

[0009] Step S3, primary reaction treatment: the calcined product is cooled to room temperature and ground in an agate bowl grinder. After grinding, it is mixed with deionized water and placed in a constant temperature water bath for constant temperature stirring reaction, so that lithium, aluminum and sodium elements in it enter the solution. Solid-liquid separation is performed to obtain filter residue A and filtrate A.

[0010] Step S4, secondary reaction treatment: Sodium hydroxide is added to filtrate A to adjust the pH to 8-9 and the solution is placed in a constant temperature water bath. After stirring at a constant temperature, aluminum ions are precipitated to form aluminum hydroxide. Solid-liquid separation is performed to obtain filter residue B and filtrate B.

[0011] Step S5, three-stage reaction treatment: sodium carbonate is added to filtrate B and placed in a constant temperature water bath for constant temperature stirring reaction, and filtered to obtain filter residue C and filtrate C with calcium carbonate as the main component.

[0012] Step S6, lithium extraction treatment: the filtrate C is concentrated, a saturated sodium carbonate solution is added to the concentrated solution, and the mixture is placed in a constant temperature water bath and stirred at a constant temperature to react, so that lithium ions combine with carbonate ions to form lithium carbonate precipitate. The filtrate D and filter residue D are obtained by filtration. After the filter residue D is washed with water three times and dried, the lithium carbonate product is obtained.

[0013] Preferably, in step S1, the grinding process is carried out by using a vibratory mill to crush and grind the material, and then passing it through a 200-mesh sieve. During the drying process, the temperature in the oven is 105°C and the drying time is 12 hours.

[0014] Preferably, in step S2, the dried overhaul residue, calcium oxide, and deionized water are mixed in a mass ratio of 3:1:1.

[0015] Preferably, in step S2, the temperature of the muffle furnace during the calcination process is 500°C, and the calcination time is 3 hours.

[0016] Preferably, the ratio of solid to liquid during the solid-liquid mixing in step S3 is 1:3 for the calcined product after grinding and deionized water.

[0017] Preferably, in step S3, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 85°C, and the reaction time is 3 hours.

[0018] Preferably, in step S4, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 75°C, and the reaction time is 3 hours.

[0019] Preferably, in step S4, after the filter residue B is dried, it is transferred to a muffle furnace and calcined at a drying temperature of 550°C for 3 hours to obtain an alumina product.

[0020] Preferably, in step S5, filtrate B is sent for testing before use to detect and analyze the calcium ion concentration in filtrate B, and sodium carbonate is added according to the calcium ion concentration at a ratio coefficient of 1.3 to 1.5.

[0021] Preferably, the method further includes the following steps:

[0022] Step S7: Filtrate D is sent for testing to analyze the carbonate ion concentration. Based on the carbonate ion concentration, an excess of 5% sulfuric acid solution is added for decarbonation. After decarbonation, the solution is freeze-crystallized to precipitate sodium sulfate, which is then dried to obtain anhydrous sodium sulfate.

[0023] Compared with related technologies, the method for recovering lithium from aluminum electrolysis overhaul slag provided by this invention has the following advantages:

[0024] It can efficiently recover metal elements from aluminum electrolysis overhaul slag, including lithium and aluminum. During the lithium recovery process, fluorine can also be fixed to reduce environmental pollution. Furthermore, it can produce high-purity lithium carbonate and alumina products, realizing the metal recovery and comprehensive utilization of waste resources and maximizing economic benefits. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 A system diagram of a first embodiment of the method for recovering lithium from aluminum electrolysis overhaul slag provided by the present invention;

[0027] Figure 2 This is a system diagram of a second embodiment of the method for recovering lithium from aluminum electrolysis overhaul slag provided by the present invention;

[0028] Figure 3 A three-dimensional view of the first embodiment of the agate bowl grinding machine provided by the present invention;

[0029] Figure 4 for Figure 3 The front view of the AA cross-sectional structure shown;

[0030] Figure 5 for Figure 4 The right view of the BB cross-sectional structure shown;

[0031] Figure 6 for Figure 3 The top view of the docking block connection structure shown;

[0032] Figure 7 for Figure 3 The diagram shows the structure of the grinding mechanism adjusted to the retracted mode;

[0033] Figure 8A three-dimensional view of the second embodiment of the agate bowl grinding machine provided by the present invention;

[0034] Figure 9 for Figure 8 The diagram shows a structural schematic of the CC cross-section.

[0035] Figure 10 for Figure 9 Left view of the gear connection structure shown;

[0036] Figure 11 for Figure 9 The diagram shows the principle of movement of the synchronous rack; where, Figure 11 (a) in the diagram shows the distribution of the synchronous racks during the upward movement of the connecting frame. Figure 11 (b) in the diagram shows the distribution of the synchronous rack after the connecting frame has been fully moved upwards;

[0037] Figure 12 for Figure 11 The diagram shown illustrates the principle of synchronous rotation of the turbulence scraper. Figure 12 (a) in the middle is Figure 9 Distribution diagram of the turbulence scraper under the condition. Figure 12 (b) in the middle is Figure 11 The distribution diagram of the turbulence scraper in state (a) is shown. Figure 12 (c) in the middle is Figure 11 Distribution diagram of the turbulence scraper in state (b).

[0038] Explanation of icon numbers:

[0039] 1. Mounting frame; 101. Adjustment slot; 11. Support partition;

[0040] 2. Rotating mechanism; 21. First driving component; 22. Rotating disk; 23. Bowl body; 231. Connecting groove; 24. Connecting block;

[0041] 3. Limiting mechanism; 31. Connecting rod; 32. Sliding sleeve; 33. Pressure ring;

[0042] 4. Lifting mechanism; 41. Telescopic component; 42. Connecting frame; 43. Support frame;

[0043] 5. Grinding mechanism; 51. Second driving component; 52. Rotating head; 53. Grinding rod;

[0044] 6. Ball rolling mechanism; 61. Pulley; 62. Traction rope; 63. Grinding ball;

[0045] 7. Aerodynamic mechanism; 71. Third drive component; 72. Aerodynamic scraper; 711. Rotating shaft; 712. Gear; 713. Elastic support component; 714. Synchronous rack; 715. Trapezoidal carriage.

[0046] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0048] This invention provides a method for recovering lithium from aluminum electrolysis overhaul slag.

[0049] First embodiment:

[0050] Please see Figure 1 The method for recovering lithium from aluminum electrolysis overhaul slag in this invention includes the following steps:

[0051] Step S1, raw material pretreatment: the aluminum electrolysis overhaul slag is ground and then dried for later use.

[0052] Step S2, Fluorine fixation treatment: The dried overhaul residue, calcium oxide and deionized water are mixed evenly according to the mixing ratio, and then placed in a muffle furnace for calcination treatment, so that the fluorine in the overhaul residue reacts with the calcium oxide to generate calcium fluoride.

[0053] Step S3, primary reaction treatment: the calcined product is cooled to room temperature and ground in an agate bowl grinder. After grinding, it is mixed with deionized water and placed in a constant temperature water bath for constant temperature stirring reaction, so that lithium, aluminum and sodium elements in it enter the solution. Solid-liquid separation is performed to obtain filter residue A and filtrate A.

[0054] Step S4, secondary reaction treatment: Sodium hydroxide is added to filtrate A to adjust the pH to 8-9 and the solution is placed in a constant temperature water bath. After stirring at a constant temperature, aluminum ions are precipitated to form aluminum hydroxide. Solid-liquid separation is performed to obtain filter residue B and filtrate B.

[0055] Step S5, three-stage reaction treatment: sodium carbonate is added to filtrate B and placed in a constant temperature water bath for constant temperature stirring reaction, and filtered to obtain filter residue C and filtrate C with calcium carbonate as the main component.

[0056] Step S6, lithium extraction treatment: the filtrate C is concentrated, a saturated sodium carbonate solution is added to the concentrated solution, and the mixture is placed in a constant temperature water bath and stirred at a constant temperature to react, so that lithium ions combine with carbonate ions to form lithium carbonate precipitate. The filtrate D and filter residue D are obtained by filtration. After the filter residue D is washed with water three times and dried, the lithium carbonate product is obtained.

[0057] Specifically, in step S1, the grinding process involves using a vibratory mill to crush and grind the material, which is then passed through a 200-mesh sieve. During the drying process, the temperature in the oven is 105°C, and the drying time is 12 hours.

[0058] Specifically, in step S2, the dried overhaul residue, calcium oxide, and deionized water are mixed in a mass ratio of 3:1:1.

[0059] Specifically, in step S2, the temperature of the muffle furnace during the roasting process is 500°C, and the roasting time is 3 hours.

[0060] Specifically, in step S3, the ratio of solid to liquid during mixing is 1:3 for the calcined product after grinding and deionized water.

[0061] Specifically, in step S3, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 85°C, and the reaction time is 3 hours.

[0062] Specifically, in step S4, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 75°C, and the reaction time is 3 hours.

[0063] Specifically, in step S4, after the filter residue B is dried, it is transferred to a muffle furnace, where it is dried at a temperature of 550°C and calcined for 3 hours. After discharge, alumina product is obtained.

[0064] Specifically, in step S5, filtrate B is sent for testing before use to detect and analyze the calcium ion concentration in filtrate B, and sodium carbonate is added according to the calcium ion concentration at a ratio of 1.3 to 1.5.

[0065] Specifically, in step S5, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 85°C, and the reaction time is 3 hours.

[0066] Specifically, in step S6, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 90°C, and the reaction time is 4 hours.

[0067] Beneficial effects:

[0068] It can efficiently recover metal elements from aluminum electrolysis overhaul slag, including lithium and aluminum. During the lithium recovery process, fluorine can also be fixed to reduce environmental pollution. Furthermore, it can produce high-purity lithium carbonate and alumina products, realizing the metal recovery and comprehensive utilization of waste resources and maximizing economic benefits.

[0069] Second embodiment:

[0070] Please see Figure 2Based on the method for recovering lithium from aluminum electrolysis overhaul slag provided in the first embodiment of the present invention, the second embodiment of the present invention proposes another method for recovering lithium from aluminum electrolysis overhaul slag. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0071] Specifically, the method for recovering lithium from aluminum electrolysis overhaul slag provided in the second embodiment of the present invention differs in that it further includes the following steps:

[0072] Step S7: Filtrate D is sent for testing to analyze the carbonate ion concentration. Based on the carbonate ion concentration, an excess of 5% sulfuric acid solution is added for decarbonation. After decarbonation, the solution is freeze-crystallized to precipitate sodium sulfate, which is then dried to obtain anhydrous sodium sulfate.

[0073] Beneficial effects:

[0074] It can efficiently recover lithium and aluminum from aluminum electrolysis overhaul slag, while fixing fluorine to reduce environmental pollution, and produce high-purity alumina, lithium carbonate and sodium sulfate products, realizing the recycling of multiple elements.

[0075] Experimental Example 1:

[0076] Step S1: After grinding the aluminum electrolysis overhaul slag in a vibratory mill, pass it through a 200-mesh sieve and dry it in an oven at 105℃ for 12 hours for later use.

[0077] Step S2: Weigh 500g of dried overhaul residue, calcium oxide and deionized water and mix them evenly in a mass ratio of 3:1:1. Place the mixed material into a muffle furnace and calcine at 500℃ for 3 hours so that the fluorine in the overhaul residue reacts with the calcium oxide to form calcium fluoride, thereby fixing the fluorine and decomposing the water-insoluble cryolite.

[0078] Step S3: Cool the calcined product to room temperature and grind it using an agate bowl grinder. Mix the ground calcined product with deionized water at a solid-liquid ratio of 1:3 and place it in a constant temperature water bath. Stir at 350 rpm and react at 75°C for 3 hours to allow lithium, aluminum and sodium elements to enter the solution. Separate the solid and liquid to obtain filter residue A and filtrate A. Filter residue A can be used as building material.

[0079] Step S4: Add sodium hydroxide to filtrate A to adjust the pH to 8.5 and place it in a constant temperature water bath. Stir at 350 rpm and react at 75°C for 3 hours to precipitate aluminum ions into aluminum hydroxide. Separate the solid and liquid to obtain filter residue B and filtrate B. After drying, filter residue B is transferred to a muffle furnace and calcined at 550°C for 3 hours to obtain alumina product.

[0080] Step S5: Sodium carbonate is added to filtrate B according to the calcium ion concentration at a ratio of 1.3, and the mixture is placed in a constant temperature water bath and reacted at 75°C for 3 hours with stirring at 350 rpm. The mixture is then filtered to obtain filter residue C, which is mainly composed of calcium carbonate, and filtrate C.

[0081] Step S6: Concentrate the filtrate C to increase the lithium ion concentration in the solution. Add saturated sodium carbonate solution to the concentrated solution and place it in a constant temperature water bath. Stir at 350 rpm and react at 95°C for 4 hours to allow lithium ions to combine with carbonate ions to form lithium carbonate precipitate. Filter to obtain filter residue D and filtrate D. After three water washings and drying, the lithium carbonate product is obtained.

[0082] Step S7: Filtrate D is sent for analysis. Based on the carbonate ion concentration, an excess of 5% sulfuric acid solution is added for decarbonation. After decarbonation, the sodium sulfate is frozen and crystallized to obtain Glauber's salt. Glauber's salt is dried to obtain sodium sulfate (anhydrous sodium sulfate).

[0083] Experimental Example 2:

[0084] Step S1: After pulverizing and grinding the aluminum electrolysis overhaul slag in a vibratory mill, pass it through a 200-mesh sieve and place it in an oven to dry at 105℃ for 12 hours for later use.

[0085] Step S2: Weigh 1000g of dried overhaul residue, calcium oxide and deionized water and mix them evenly in a mass ratio of 5:2:2. Place the mixed material into a muffle furnace and calcine at 550℃ for 2 hours so that the fluorine in the overhaul residue reacts with the calcium oxide to form calcium fluoride, thereby fixing the fluorine and decomposing the water-insoluble cryolite.

[0086] Step S3: Cool the calcined product to room temperature and grind it using an agate bowl grinder. Mix the ground calcined product with deionized water at a solid-liquid ratio of 1:4 and place it in a constant temperature water bath. Stir at 350 rpm and react at 85°C for 3 hours to allow lithium, aluminum and sodium elements to enter the solution. Separate the solid and liquid to obtain filter residue A and filtrate A. Filter residue A can be used as building material.

[0087] Step S4: Add sodium hydroxide to filtrate A to adjust the pH to 8.0 and place it in a constant temperature water bath. Stir at 350 rpm and react at 85°C for 3 hours to precipitate aluminum ions into aluminum hydroxide. Separate the solid and liquid to obtain filter residue B and filtrate B. After drying, filter residue B is transferred to a muffle furnace and calcined at 500°C for 3 hours to obtain alumina product.

[0088] Step S5: Sodium carbonate is added to filtrate B according to the calcium ion concentration at a ratio of 1.5, and the mixture is placed in a constant temperature water bath and reacted at 85°C for 3 hours with stirring at 350 rpm. The mixture is then filtered to obtain filter residue C, which is mainly composed of calcium carbonate, and filtrate C.

[0089] Step S6: Concentrate the filtrate C to increase the lithium ion concentration in the solution. Add saturated sodium carbonate solution to the concentrated solution and place it in a constant temperature water bath. Stir at 350 rpm and react at 90°C for 4 hours to allow lithium ions to combine with carbonate ions to form lithium carbonate precipitate. Filter to obtain filter residue D and filtrate D. After three water washings and drying, the lithium carbonate product is obtained.

[0090] Step S7: Filtrate D is sent for analysis. Based on the carbonate ion concentration, an excess of 8% sulfuric acid solution is added for decarbonation. After decarbonation, the sodium sulfate is frozen and crystallized to obtain Glauber's salt. Glauber's salt is dried to obtain sodium sulfate (anhydrous sodium sulfate).

[0091] Ultimately, it can be concluded that:

[0092] The method for recovering lithium from aluminum electrolysis overhaul slag provided in this application is based on the core of "solid fluorine-leaching-separation-crystallization". Combined with experimental examples and production parameters, it solves the environmental pollution and resource waste problems existing in the treatment of overhaul slag in the prior art, realizes the harmless treatment and resource recycling of overhaul slag, improves the resource utilization rate in the aluminum electrolysis production process, and creates more economic value.

[0093] The method of this invention can effectively recover lithium and aluminum from waste aluminum electrolysis overhaul slag and produce high-purity alumina, lithium carbonate and sodium sulfate products, which have good market application prospects.

[0094] The present invention also provides an agate bowl grinding mill for grinding the product after roasting in the method for recovering lithium from aluminum electrolysis overhaul slag.

[0095] First embodiment:

[0096] Please refer to the following: Figures 3 to 5 In this embodiment, the agate bowl grinding machine includes:

[0097] Mounting rack 1;

[0098] The rotating mechanism 2 includes a first driving member 21, a rotating disk 22, and a bowl 23. The first driving member 21 is fixedly installed in the mounting frame 1. The rotating part of the first driving member 21 passes through the mounting frame 1 and is fixedly connected to the rotating disk 22. The bottom of the bowl 23 is supported and installed on the top of the rotating disk 22.

[0099] Lifting mechanism 4, which is mounted on the mounting frame 1;

[0100] Grinding mechanism 5, which is installed in the lifting part of lifting mechanism 4;

[0101] The limiting mechanism 3 includes a connecting rod 31, a sliding sleeve 32, and a pressing ring 33. The top of the connecting rod 31 is fixedly connected to the lifting part of the lifting mechanism 4, the top of the sliding sleeve 32 is fixedly connected to the bottom of the connecting rod 31, and the pressing ring 33 is rotatably installed inside the sliding sleeve 32. The bottom of the pressing ring 33 is pressed against the top of the bowl 23.

[0102] A ball rolling mechanism 6 is installed inside the bowl body 23;

[0103] The turbulence mechanism 7 includes a third driving member 71 and a turbulence scraper 72. The third driving member 71 is fixedly installed in the lifting part of the lifting mechanism 4. One end of the turbulence scraper 72 is fixedly connected to the rotating part of the third driving member 71. The bottom of the turbulence scraper 72 is inserted obliquely into the interior of the bowl 23.

[0104] In this embodiment, the first driving component 21 is a motor structure. The fixed end of the motor structure is fixed inside the mounting frame 1, and the driving part of the motor structure passes through the mounting frame 1 and is fixedly connected to the rotating disk 22.

[0105] In this embodiment, the lifting mechanism 4 is used to drive the grinding mechanism 5 and the limiting mechanism 3 to lift and adjust as a whole.

[0106] In this embodiment, the grinding mechanism 5 includes two usage modes:

[0107] In the grinding mode, the bottom of the clamping ring 33 abuts against the top of the bowl 23, the grinding part of the grinding mechanism 5 is inserted into the interior of the bowl 23, the ball rolling mechanism 6 is installed inside the bowl 23, the rotating disk 22 rotates synchronously driving the bowl 23 to rotate, the grinding mechanism 5 controls the ball rolling mechanism 6 to sway inside the bowl 23 when it rotates, and the turbulence scraper 72 is inserted into the range of the bowl 23.

[0108] In the retracted mode, the bottom of the clamping ring 33 separates from the top of the bowl 23, the grinding part of the grinding mechanism 5 detaches from the interior of the bowl 23, and a clearance is reserved for the installation of the bowl 23. The ball rolling mechanism 6 is removed from the range of the bowl 23, and the turbulence scraper 72 rotates upward to retract.

[0109] In this embodiment, when the turbulence scraper 72 is inserted into the interior of the bowl 23, the turbulence scraper 72 facilitates scraping and turbulence of the material in the bowl 23 during operation, making the material grinding distribution more uniform.

[0110] Grinding principle:

[0111] Before using the equipment, adjust the equipment to the grinding mode and put the material to be ground into the bowl 23;

[0112] The first driving component 21 and the grinding mechanism 5 are activated. The first driving component 21 drives the rotating disk 22 to rotate, and the rotating disk 22 drives the bowl 23 and the clamping ring 33 to rotate synchronously, so as to rotate the material inside the bowl 23. While the bowl 23 is rotating, the grinding mechanism 5 cooperates with the ball rolling mechanism 6 to grind the material inside the bowl 23, so as to achieve fine grinding of the material.

[0113] Equipment adjustment principle:

[0114] When it is necessary to remove the bowl 23, the lifting mechanism 4 is activated, and the lifting mechanism 4 drives the grinding mechanism 5 to move upward, so that the grinding part of the grinding mechanism 5 is removed from the range of the bowl 23.

[0115] As the grinding mechanism 5 moves upward, it drives the connecting rod 31 to move upward. The connecting rod 31 drives the clamping ring 33 to move upward through the sliding sleeve 32, so that the clamping ring 33 separates from the top of the bowl 23, thereby unlocking the bowl 23 and providing space for removing the bowl 23, making it easy to remove the bowl 23 after grinding.

[0116] When the bowl 23 needs to be reassembled and used, first install the bowl 23 on the top of the rotating disk 22, align the top of the bowl 23 with the bottom of the clamping ring 33, start the lifting mechanism 4, the lifting mechanism 4 drives the grinding mechanism 5 to move down, so that the grinding part of the grinding mechanism 5 is inserted into the range of the bowl 23.

[0117] As the grinding mechanism 5 moves downward, it drives the connecting rod 31 to move downward. The connecting rod 31 drives the clamping ring 33 to move downward through the sliding sleeve 32, so that the clamping ring 33 abuts against the top of the bowl 23, making the bowl 23 stably connected to the rotating disk 22, which facilitates stable rotation adjustment of the bowl 23 during grinding.

[0118] This facilitates automatic docking between the clamping ring 33 and the bowl 23 during the process of switching the equipment from the retracted mode to the grinding mode; and automatic separation between the clamping ring 33 and the bowl 23 during the process of switching the equipment from the grinding mode to the retracted mode, providing convenience for the replacement and use of the bowl 23.

[0119] In an optional embodiment of this example, the third driving component 71 can be a motor structure. The third driving component 71 is fixedly installed on the lifting mechanism 4, which facilitates direct driving of the turbulence scraper 72 for rotational adjustment and allows for individual control of the turbulence scraper 72.

[0120] For details, please refer to the following: Figure 4 and Figure 5 The grinding mechanism 5 includes a second driving member 51, a rotating head 52, and a grinding rod 53. The second driving member 51 is installed in the lifting part of the lifting mechanism 4. The rotating head 52 is fixed in the rotating part of the second driving member 51. The top of the grinding rod 53 is fixedly connected to the rotating head 52, and the bottom of the grinding rod 53 is inserted into the bowl 23.

[0121] In this embodiment, the second driving component 51 is a motor structure, which provides independent power for the rotation adjustment of the rotating head 52 and the grinding rod 53.

[0122] In this embodiment, when the equipment is running, the rotation direction of the grinding rod 53 is opposite to the rotation direction of the bowl 23, which facilitates stable grinding of the material.

[0123] Grinding principle:

[0124] Before grinding, raw materials are added to the inside of the bowl 23, the third drive unit 71 is activated, the third drive unit 71 drives the turbulence scraper 72 to rotate and adhere to the inner wall of the bowl 23, and the ball rolling mechanism 6 is inserted into the inside of the bowl 23.

[0125] During grinding, the first drive unit 21 is activated, which drives the rotating disk 22 to rotate clockwise, and the rotating disk 22 drives the bowl 23 and the clamping ring 33 to rotate clockwise.

[0126] The second drive unit 51 is activated, which drives the rotating head 52 to rotate counterclockwise. The rotating head 52 drives the grinding rod 53 to rotate and swing counterclockwise. On the one hand, it grinds the material in the bowl 23, and on the other hand, it pushes the ball rolling mechanism 6 to shake in the bowl 23, thereby facilitating the comprehensive grinding of the material in the bowl 23.

[0127] Please refer to the following: Figure 3 and Figure 4 The mounting frame 1 is provided with an adjustment groove 101, and the support partition 11 is fixed on the mounting frame 1 and located within the range of the adjustment groove 101;

[0128] The lifting mechanism 4 includes a telescopic member 41, a connecting frame 42, and a support frame 43. The bottom of the telescopic member 41 is fixedly connected to the mounting frame 1. The bottom of the connecting frame 42 is fixedly connected to the telescopic part of the telescopic member 41. The support frame 43 is fixedly mounted on the connecting frame 42. The top of the connecting rod 31 is fixedly connected to the support frame 43. The second driving member 51 is fixedly mounted on the support frame 43. The third driving member 71 is mounted on the support frame 43.

[0129] When the grinding rod 53 is fully inserted into the bowl 23, the bottom of the support frame 43 is supported on the top of the support partition 11.

[0130] In this embodiment, the telescopic member 41 can be an electric telescopic rod, used to drive the connecting frame 42 to stably lift and adjust within the range of the adjustment groove 101.

[0131] In this embodiment, the support partition 11 provides limiting and auxiliary support for the overall lifting and adjusting of the support frame 43, so as to ensure the stability of the grinding mechanism 5 during operation.

[0132] Lifting adjustment principle:

[0133] When it is necessary to remove the grinding rod 53 from the bowl 23, the telescopic component 41 is activated. The telescopic component 41 drives the connecting frame 42 to move upward, the connecting frame 42 drives the support frame 43 to move upward, and the support frame 43 drives the second driving component 51, the rotating head 52, and the grinding rod 53 to move upward as a whole and move out of the bowl 23. At the same time as the support frame 43 moves upward, the connecting rod 31 synchronously drives the sliding sleeve 32 to move upward, and the sliding sleeve 32 drives the clamping ring 33 to move upward.

[0134] When it is necessary to insert the grinding rod 53 into the bowl 23, the telescopic component 41 is activated. The telescopic component 41 drives the connecting frame 42 to move down, the connecting frame 42 drives the support frame 43 to move down, and the support frame 43 drives the second driving component 51, the rotating head 52 and the grinding rod 53 to move down as a whole and insert into the bowl 23. At the same time as the support frame 43 moves down, the connecting rod 31 drives the sliding sleeve 32 to move down, and the sliding sleeve 32 drives the clamping ring 33 to move down.

[0135] Please refer to the following: Figure 3 and Figure 4 The ball rolling mechanism 6 includes a pulley 61, a traction rope 62, and a grinding ball 63. The top of the pulley 61 is fixed to the bottom of the support frame 43. One end of the traction rope 62 is fixedly connected to the support partition 11, and the other end of the traction rope 62 passes through the pulley 61 and is fixedly connected to the grinding ball 63.

[0136] When the device is in grinding mode, the grinding ball 63 is automatically inserted into the bowl 23; when the device is in retracted mode, the grinding ball 63 is automatically removed from the maintenance range of the bowl 23.

[0137] When the device switches from grinding mode to retracting mode, the pulley 61 moves upward synchronously with the support frame 43. As the pulley 61 moves upward, the traction rope 62 adaptively pulls the grinding ball 63 upward, so that the grinding ball 63 automatically leaves the range of the bowl 23.

[0138] When the device switches from the retracted mode to the grinding mode, the pulley 61 moves down synchronously with the support frame 43. At the same time as the pulley 61 moves down, the grinding ball 63 moves down adaptively under the action of gravity and falls into the range of the bowl 23.

[0139] This allows for the adaptive installation or lifting of the grinding balls 63 during equipment mode switching, enabling automated equipment adjustment.

[0140] Preferably, two ball-rolling mechanisms 6 are provided, symmetrically arranged on both sides of the rotation range of the grinding rod 53. Increasing the number of ball-rolling mechanisms 6 improves material grinding efficiency.

[0141] For details, please refer to the following: Figure 4 and Figure 6 The rotating disk 22 has a fixed docking block 24 on its top. The docking block 24 has a rectangular structure. The bottom of the bowl 23 has a docking groove 231. The top of the docking block 24 is inserted into the docking groove 231 and engages with the bowl 23.

[0142] After the docking block 24 is inserted into the docking groove 231, the rotating disk 22 can stably drive the bowl 23 to rotate through the docking block 24. When the bowl 23 rotates, it drives the material inside to rotate, providing rotational power for grinding the material.

[0143] The working principle of the agate bowl grinder provided in this embodiment is as follows:

[0144] like Figure 4 As shown, let's define that in the initial state, the device is in the grinding state;

[0145] Combination Figures 4 to 7 When the material in the bowl 23 is ground, the telescopic component 41 is activated, the telescopic component 41 drives the connecting frame 42 to move upward, and the connecting frame 42 drives the support frame 43 to move upward.

[0146] When the support frame 43 moves upward, it drives the second driving member 51 to move upward, the second driving member 51 drives the rotating head 52 to move upward, and the rotating head 52 drives the grinding rod 53 to move upward, so that the grinding rod 53 is removed from the range of the bowl 23 and provides clearance space for the removal of the bowl 23.

[0147] When the support frame 43 moves upward, it also drives the connecting rod 31 to move upward. The connecting rod 31 drives the sliding sleeve 32 to move upward. The sliding sleeve 32 drives the pressing ring 33 to move upward. The pressing ring 33 is completely separated from the bowl body 23.

[0148] When the support frame 43 moves upward, it also drives the pulley 61 to move upward. At the same time as the pulley 61 moves upward, the grinding ball 63 is driven to move upward adaptively through the traction rope 62. The grinding ball 63 automatically leaves the range of the bowl 23 and retracts to the bottom of the support frame 43.

[0149] Combination Figures 7 to 4 First, align and insert the docking groove 231 at the bottom of the bowl 23 with the docking block 24, then activate the telescopic component 41. The telescopic component 41 drives the connecting frame 42 to move down, and the connecting frame 42 drives the support frame 43 to move down.

[0150] When the support frame 43 moves down, it drives the second driving member 51 to move down, the second driving member 51 drives the rotating head 52 to move down, and the rotating head 52 drives the grinding rod 53 to move down, so that the grinding rod 53 is reinserted into the range of the bowl 23.

[0151] When the support frame 43 moves upward, it also drives the connecting rod 31 to move downward. The connecting rod 31 drives the sliding sleeve 32 to move downward, and the sliding sleeve 32 drives the pressing ring 33 to move downward. The bottom of the pressing ring 33 abuts against the top of the bowl 23.

[0152] When the support frame 43 moves upward, it also drives the pulley 61 to move downward. At the same time as the pulley 61 moves downward, the grinding ball 63 moves downward adaptively under its own gravity and falls within the range of the bowl 23.

[0153] This allows the grinding mechanism 5 to switch from grinding mode to retracting mode while simultaneously unlocking the bowl 23 and causing the grinding balls 63 to retract adaptively; and simultaneously locks the bowl 23 and adaptively deploys the grinding balls 63 while switching from retracting mode to grinding mode.

[0154] Second embodiment:

[0155] Please refer to the following: Figures 8 to 10Based on the agate grinding mill provided in the first embodiment of the present invention, the second embodiment of the present invention proposes another agate grinding mill. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0156] Specifically, the difference in the agate bowl grinding machine provided in the second embodiment of the present invention is that the third driving component 71 includes a rotating shaft 711, a gear 712, an elastic support 713, a synchronous rack 714, and a trapezoidal slide 715. One end of the rotating shaft 711 passes through the support frame 43 and is fixedly connected to the turbulence scraper 72. The other end of the rotating shaft 711 passes through the connecting frame 42 and is fixedly connected to the gear 712. The rotating shaft 711 is rotatably installed between the support frame 43 and the connecting frame 42. One end of the elastic support 713 is fixedly connected to the connecting frame 42. The other end of the elastic support 713 is fixedly connected to one end of the synchronous rack 714. The bottom of the synchronous rack 714 is meshed with the gear 712. The trapezoidal slide 715 is fixedly mounted on the mounting frame 1 and located within the range of the adjusting groove 101. The other end of the synchronous rack 714 abuts against the trapezoidal slide 715 and is slidably connected.

[0157] When the device is in grinding mode, the synchronous rack 714 abuts against the protrusion of the trapezoidal carriage 715; when the device is in retracted mode, the synchronous rack 714 abuts against the recess of the trapezoidal carriage 715.

[0158] In this embodiment, the trapezoidal carriage 715 includes a protrusion, an inclined portion, and a recess;

[0159] like Figure 9 and Figure 12 As shown in (a), when the equipment is in grinding mode, the synchronous rack 714 abuts against the protrusion of the trapezoidal carriage 715; the turbulence scraper 72 extends downward to scrape the material in the bowl 23.

[0160] like Figure 11 (a) and Figure 12 As shown in (b), during the process of switching the device from grinding mode to retracting mode, the synchronous rack 714 abuts against the inclined part of the trapezoidal carriage 715; the turbulence scraper 72 rotates upward.

[0161] like Figure 11 (b) and Figure 12 As shown in (c), when the device is in the retracted mode, the synchronous rack 714 abuts against the recess of the trapezoidal carriage 715; the turbulence scraper 72 is completely folded up.

[0162] Equipment operating principle:

[0163] Combination Figures 9 to 11 (a) to Figure 11 In (b), when the telescopic member 41 drives the connecting frame 42 to move upward, the connecting frame 42 drives the support frame 43 to move upward as a whole, and the connecting frame 42 also drives the rotating shaft 711, the gear 712, the elastic support member 713 and the synchronous rack 714 to move upward synchronously;

[0164] As the synchronous rack 714 moves upward, its right end abuts against the protrusion of the trapezoidal slide 715 and slides upward. Simultaneously, the elastic support 713 elastically pushes the synchronous rack 714 into stable contact with the trapezoidal slide 715. The right end of the synchronous rack 714 passes sequentially through the protrusion, inclined portion, and recessed portion of the trapezoidal slide 715, causing the synchronous rack 714 to move to the right.

[0165] During the process of the synchronous rack 714 moving to the right, the synchronous rack 714 drives the gear 712 to rotate, the gear 712 drives the rotating shaft 711 to rotate clockwise, and the rotating shaft 711 drives the turbulence scraper 72 to rotate clockwise, so that the turbulence scraper 72 switches from the use state to the folded state.

[0166] Combination Figure 11 (b) to Figure 11 (a) to Figure 9 When the telescopic member 41 drives the connecting frame 42 to move downward, the connecting frame 42 drives the support frame 43 to move downward as a whole. The connecting frame 42 also drives the rotating shaft 711, the gear 712, the elastic support member 713 and the synchronous rack 714 to move downward synchronously.

[0167] As the synchronous rack 714 moves downward, its right end abuts against the recess of the trapezoidal slide 715 and slides downward. Simultaneously, the elastic support 713 elastically pushes the synchronous rack 714 into stable contact with the trapezoidal slide 715. The right end of the synchronous rack 714 passes sequentially through the recess, inclined portion, and protrusion of the trapezoidal slide 715, causing the synchronous rack 714 to move to the left.

[0168] During the leftward movement of the synchronous rack 714, the synchronous rack 714 drives the gear 712 to rotate, the gear 712 drives the rotating shaft 711 to rotate counterclockwise, and the rotating shaft 711 drives the turbulence scraper 72 to rotate counterclockwise, so that the turbulence scraper 72 switches from the folded state to the use state.

[0169] This allows the turbulence scraper 72 to switch from the used state to the folded state simultaneously during the process of switching the device from the grinding mode to the retracted mode; and it also allows the turbulence scraper 72 to switch from the folded state to the used state simultaneously during the process of switching the device from the retracted mode to the grinding mode.

[0170] The working principle of the agate bowl grinder provided in this embodiment:

[0171] A1, when the grinding mechanism 5 switches from the grinding mode to the retracted mode, the synchronous rack 714 slides upward along the surface of the trapezoidal slide 715;

[0172] A2, while the synchronous rack 714 slides upward on the surface of the trapezoidal carriage 715, the elastic support 713 pushes the synchronous rack 714 to move adaptively to the right. While the synchronous rack 714 moves to the right, it simultaneously drives the turbulence scraper 72 to rotate clockwise. The turbulence scraper 72 adaptively switches from the use state to the folded state.

[0173] A3, when the grinding mechanism 5 switches from the retracted mode to the grinding mode, the synchronous rack 714 slides downward along the surface of the trapezoidal slide 715;

[0174] A4, while the synchronous rack 714 slides downward on the surface of the trapezoidal carriage 715, the synchronous rack 714 adaptively moves to the left under the abutment action of the trapezoidal carriage 715. At the same time as the synchronous rack 714 moves to the left, it synchronously drives the turbulence scraper 72 to rotate counterclockwise. The turbulence scraper 72 adaptively switches from the folded state to the folded use state.

[0175] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for recovering lithium from aluminum electrolysis overhaul slag, characterized in that, Includes the following steps: Step S1, raw material pretreatment: the aluminum electrolysis overhaul slag is ground and then dried for later use. Step S2, Fluorine fixation treatment: The dried overhaul residue, calcium oxide and deionized water are mixed evenly according to the mixing ratio, and then placed in a muffle furnace for calcination treatment, so that the fluorine in the overhaul residue reacts with the calcium oxide to generate calcium fluoride. Step S3, primary reaction treatment: the calcined product is cooled to room temperature and ground in an agate bowl grinder. After grinding, it is mixed with deionized water and placed in a constant temperature water bath for constant temperature stirring reaction, so that lithium, aluminum and sodium elements in it enter the solution. Solid-liquid separation is performed to obtain filter residue A and filtrate A. Step S4, secondary reaction treatment: Sodium hydroxide is added to filtrate A to adjust the pH to 8-9 and the solution is placed in a constant temperature water bath. After stirring at a constant temperature, aluminum ions are precipitated to form aluminum hydroxide. Solid-liquid separation is performed to obtain filter residue B and filtrate B. Step S5, three-stage reaction treatment: sodium carbonate is added to filtrate B and placed in a constant temperature water bath for constant temperature stirring reaction, and filtered to obtain filter residue C and filtrate C with calcium carbonate as the main component. Step S6, lithium extraction treatment: concentrate the filtrate C, add saturated sodium carbonate solution to the concentrated solution, place it in a constant temperature water bath and stir to react, so that lithium ions combine with carbonate ions to form lithium carbonate precipitate, filter to obtain filter residue D and filtrate D, filter residue D is washed and dried three times to obtain lithium carbonate product. The agate bowl grinding machine includes: Install rack; A rotating mechanism, comprising a first driving member, a rotating disk, and a bowl, wherein the first driving member is fixedly disposed within the mounting frame, and the rotating part of the first driving member passes through the mounting frame and is fixedly connected to the rotating disk, and the bottom of the bowl is supported and mounted on the top of the rotating disk; A lifting mechanism, which is mounted on the mounting frame; A grinding mechanism, wherein the grinding mechanism is installed in the lifting part of the lifting mechanism; A limiting mechanism is provided, comprising a connecting rod, a sliding sleeve, and a pressing ring. The top of the connecting rod is fixedly connected to the lifting part of the lifting mechanism, the top of the sliding sleeve is fixedly connected to the bottom of the connecting rod, and the pressing ring is rotatably installed inside the sliding sleeve, with the bottom of the pressing ring pressing against the top of the bowl. A ball rolling mechanism, which is installed inside the bowl body; A flow-dispersing mechanism, comprising a third driving member and a flow-dispersing scraper, wherein the third driving member is fixedly mounted on the lifting part of the lifting mechanism, one end of the flow-dispersing scraper is fixedly connected to the rotating part of the third driving member, and the bottom of the flow-dispersing scraper is inclinedly inserted into the interior of the bowl. As the grinding mechanism moves upward, it drives the connecting rod to move upward. The connecting rod, through the sliding sleeve, drives the clamping ring to move upward, causing the clamping ring to separate from the top of the bowl, thus unlocking the bowl and providing space for removing it.

2. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 1, characterized in that, In step S1, the grinding process involves using a vibratory mill to crush and grind the material, followed by passing it through a 200-mesh sieve. During the drying process, the temperature in the oven is 105°C, and the drying time is 12 hours.

3. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 1, characterized in that, In step S2, the dried overhaul residue, calcium oxide, and deionized water are mixed in a mass ratio of 3:1:

1.

4. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 3, characterized in that, In step S2, the muffle furnace temperature is 500℃ and the roasting time is 3 hours.

5. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 1, characterized in that, In step S3, the ratio of solid to liquid during mixing is 1:3 for the calcined product after grinding and deionized water.

6. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 5, characterized in that, In step S3, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 85°C, and the reaction time is 3 hours.

7. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 1, characterized in that, In step S4, during the constant temperature stirring reaction, the constant temperature water bath is stirred at a speed of 350 rpm, the reaction temperature is 75°C, and the reaction time is 3 hours.

8. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 7, characterized in that, In step S4, after the filter residue B is dried, it is transferred to a muffle furnace and dried at a temperature of 550°C for 3 hours. After discharge, alumina product is obtained.

9. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 1, characterized in that, In step S5, filtrate B is sent for testing before use to detect and analyze the calcium ion concentration in filtrate B, and sodium carbonate is added according to the calcium ion concentration at a ratio of 1.3 to 1.

5.

10. The method for recovering lithium from aluminum electrolysis overhaul slag according to claim 9, characterized in that, It also includes the following steps: Step S7: Filtrate D is sent for testing to analyze the carbonate ion concentration. Based on the carbonate ion concentration, an excess of 5% sulfuric acid solution is added for decarbonation. After decarbonation, the solution is freeze-crystallized to precipitate sodium sulfate, which is then dried to obtain anhydrous sodium sulfate.

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