Resource recycling equipment and method for extracting lithium from waste carbon blocks

Abstract

The invention provides resource recycling equipment and method for extracting lithium from waste carbon blocks, and relates to the technical field of metal material recycling. The resource recycling equipment comprises a combustion furnace, a mixing mechanism, an intermittent air injection mechanism and an adjusting mechanism; the mixing mechanism comprises a mixing box arranged at the top of the combustion furnace, a rotating rod is vertically and rotatably connected to the inner side of the mixing box, three mixing paddles are fixedly arranged on the surface of the rotating rod, and a mixing frame is fixedly arranged on the surface of the rotating rod and located at the bottoms of the mixing paddles. According to the scheme, the effect of intermittently spraying gas in different directions is finally achieved through continuous rotation of a convex disc, sequential circulating gas spraying of four gas cylinders through top hoses and cooperative use with an adjusting mechanism, the sprayed gas is used for mixing carbon residue powder and an alkaline compound, and after the carbon residue powder and the alkaline compound are combined, the carbon residue powder and the alkaline compound are mixed. Carbon residue powder and an alkaline compound can be fully mixed, insufficient contact of a reaction interface is avoided, the recovery effect of extracting lithium from waste carbon blocks is improved, and volatilization of harmful gas is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material recovery, and in particular to a waste carbon block lithium extraction resource recovery device and method. Background Art

[0002] Waste cathode carbon blocks from electrolytic aluminum are the main solid waste after the aluminum electrolytic cell is scrapped. Its main components are carbon materials (50-70%), which are composed of graphitized carbon and non-graphitized carbon, mainly from the cathode carbon block body; fluorides (15-30%) are mainly electrolytic permeates such as NaF and AlF3; sodium salts (5-15%) include Na3AlF6 (cryolite), NaAlO2, etc.; aluminum compounds (3-8%) Al2O3, Al(OH)3, etc.; lithium elements (0.5-3%) exist in the form of LiF, LiAlO2, etc.; other impurities (metal oxides such as Fe, Si, Ca, 2-5%), and traditional treatment methods mostly use landfill or incineration, resulting in waste of resources such as lithium and fluorine, and fluorides are easily dissolved, causing environmental pollution.

[0003] In the prior art, spent cathode carbon blocks from scrapped aluminum electrolytic cells contain lithium and fluoride over long periods of use. If directly landfilled, these lithium and fluoride can seep into the soil and groundwater, harming the ecological environment. Effective methods for extracting and recovering lithium from the waste material are environmentally friendly. Existing waste carbon block lithium recovery equipment, when calcining the material, is unable to fully mix the cathode carbon block powder with the alkaline compound. This results in inadequate contact at the reaction interface, which can easily lead to localized unreacted areas. Some fluoride cannot be converted into stable CaF2, and the remaining fluorine evaporates at high temperatures as HF or SiF4 gas.

[0004] Therefore, it is necessary to provide a waste carbon block lithium extraction resource recovery device and method to solve the above technical problems. Summary of the Invention

[0005] The present invention provides a waste carbon block lithium extraction and resource recovery device and method, which solves the technical problem in the related art that the existing waste carbon block lithium extraction and resource recovery device is not convenient for fully mixing the cathode carbon block powder and the alkaline compound during the roasting of the material.

[0006] In order to solve the above technical problems, the waste carbon block lithium resource recovery equipment provided by the present invention includes a combustion furnace, a mixing mechanism, an intermittent jet mechanism and a regulating mechanism; The mixing mechanism includes a mixing box arranged on the top of the combustion furnace, the inner side of the mixing box is vertically connected to a rotating rod, the surface of the rotating rod is fixed with three mixing paddles, and a mixing frame is fixed on the surface of the rotating rod and located at the bottom of the mixing paddles; The intermittent jet mechanism includes a mounting plate, a bracket and an air cylinder, the mounting plate is fixedly mounted on the bottom of the mixing box through a plurality of brackets, the inner side of the mounting plate is vertically rotatably connected to a rotating shaft, the top end of the rotating shaft is fixedly connected to the bottom end of the rotating rod, the keyway of the rotating shaft away from the center of the circle is connected to a convex plate, the air cylinder is distributed in a circular array with the rotating shaft as the center of the circle, the inner walls of the four air cylinders are slidably connected to pistons and movable rods, the four movable rods are respectively fixedly connected to the four pistons, the surfaces of the four movable rods are slidably connected to the inner wall of the air cylinder, the surfaces of the four movable rods and the inner side of the mounting plate are all provided with springs, the inner sides of the four movable rods are rotatably connected to rotating wheels, and the rotating wheels are tightly against the peripheral side surfaces of the convex plate; The regulating mechanism is slidably connected to the inner side of the mixing box and is used for adjusting the injection angle of the gas.

[0007] Preferably, the four gas cylinders are connected to an air inlet pipe on one side thereof, and are connected to a hose at the top and bottom thereof. A mounting bracket is fixedly provided on the circumferential side of the four gas cylinders, and the mounting bracket is fixedly connected to the top of the combustion furnace by bolts. A plurality of mounting brackets are fixedly provided on the top of the inner wall of the combustion furnace, an annular tube is fixedly provided on the inner side of the plurality of mounting brackets, and four nozzles are connected to the inner side of the annular tube.

[0008] Preferably, a mounting seat is provided on the top of the mixing box, a driving motor for driving the rotating rod to rotate is provided on the top of the mounting seat, and two feeding pipes are connected to the top of the mixing box.

[0009] Preferably, a screening mechanism is fixedly provided on the surface of the rotating rod, and the screening mechanism includes a rotating disk fixedly provided on the surface of the rotating rod, a convex plate is fixedly provided on the top of the rotating disk, a screening rack is slidably connected to the surface of the rotating rod, and three connecting racks are fixedly provided on the bottom of the screening rack, and the inner sides of the three connecting racks are rotatably connected to moving wheels, and the bottoms of the three moving wheels are in contact with the top of the rotating disk.

[0010] Preferably, the adjustment mechanism includes four sliding frames slidably connected to the inner side of the mixing box, the four sliding frames are distributed in a circular array with the rotating rod as the center, the four sliding frames are fixed with baffles on the separated sides, and the four baffles are fixed with gear plates on the opposite sides. The inner wall of the mixing box is fixed with four rotating seats in a circular array, the inner sides of the four rotating seats are rotatably connected to the air outlet pipes, the surfaces of the four air outlet pipes are fixed with gears, the gears are meshed with the gear plates, and the surfaces of the four air outlet pipes are connected to nozzles.

[0011] Preferably, one side opposite to the other of the four sliding racks is fixedly connected to the peripheral side surface of the screening rack, and the output ends of the four hoses are respectively connected to four air outlet pipes.

[0012] Preferably, a gas sensor is fixedly provided on the top of the combustion furnace, the front side of the gas sensor is connected to a pipe, the bottom end of the pipe is connected to the combustion furnace, and the top of the combustion furnace is connected to a feeding pipe.

[0013] Preferably, the right side of the combustion furnace is connected to a smoke exhaust pipe, and a base is fixedly provided at the bottom of the combustion furnace.

[0014] A method for recycling waste carbon blocks by extracting lithium as a resource comprises the following steps: S1. Preprocessing: Crushing waste carbon blocks from electrolytic aluminum to obtain carbon slag powder; S2, roasting treatment: The pretreated carbon slag powder is uniformly mixed with the alkaline compound according to a mass ratio and roasted; S3, acid leaching reaction: The roasted product is crushed and mixed with sulfuric acid solution in a solid-liquid ratio, and leaching reaction is carried out in a constant temperature water bath, and solid-liquid separation is performed to obtain a leaching solution and a leaching residue; S4, purification treatment: Calcium oxide is added to the leaching solution in sequence to adjust the pH, oxalic acid is added for deep purification, and a purified liquid and purified residue are obtained after filtration. The purified residue is washed with sulfuric acid and then added to the pickling solution for recycling. Sodium carbonate is added to the purified liquid for lithium precipitation reaction to obtain a lithium carbonate product; S5. First leaching residue treatment: The first leaching residue is mixed with a nitric acid-aluminum nitrate composite acid solution in a solid-liquid ratio, and a leaching reaction is carried out in a constant temperature water bath. After the reaction, disodium ethylenediaminetetraacetic acid is added for complexation and impurity removal. After filtration, ammonia water is added to the filtrate to adjust the pH value to 3 to 7, and aluminum fluoride product is precipitated. The residual residue can be used as fuel or building material after washing with water.

[0015] Compared with related technologies, the waste carbon block lithium resource recovery equipment and method provided by the present invention has the following beneficial effects: The mixing paddle and the mixing frame are rotated by the rotating rod to physically stir and mix the carbon slag powder and the alkaline compound. The rotation of the rotating rod will drive the rotation of the bottom rotating shaft. The rotation of the rotating shaft drives the cam to squeeze the four rotating wheels in turn, so that the movable rod drives the piston to slide in the air cylinder, squeezing the gas outward. Through the setting of the spring, when the raised position of the cam is away from the rotating wheel, the spring extends to drive the movable rod and the piston to reset, thereby drawing the gas into the air cylinder. The cam rotates continuously, and the four air cylinders circulate and spray gas in turn through the top hose. When used in conjunction with the adjustment mechanism, the effect of intermittent jetting in different directions can be achieved, and the ejected gas is used to mix the carbon slag powder and the alkaline compound. After the two are combined with each other, the carbon slag powder and the alkaline compound can be fully mixed to avoid insufficient contact at the reaction interface, improve the recovery effect of lithium extraction from waste carbon blocks, and reduce the volatilization of harmful gases. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0017] Figure 1 The best structural diagram provided by the present invention; Figure 2 A schematic diagram of the structure of the left view provided by the present invention; Figure 3 A schematic structural diagram of the intermittent jet injection mechanism provided by the present invention; Figure 4 for Figure 3 A schematic structural diagram of a cross-sectional view of the mounting plate shown; Figure 5 for Figure 4 The enlarged structural diagram of point A is shown; Figure 6 for Figure 4 The schematic diagram of the state in which the rotating shaft drives the cam to rotate, causing the movable rod to drive the piston to move; Figure 7 A schematic structural diagram of the annular tube provided by the present invention; Figure 8 A schematic structural diagram of a cross-sectional view of a mixing box provided by the present invention; Figure 9 for Figure 8 The structural diagram of the mixing mechanism shown; Figure 10 for Figure 8 The structural diagram of the regulating mechanism and the screening mechanism shown; Figure 11 for Figure 10 The enlarged structural diagram of point B is shown; Figure 12 A schematic diagram of the state in which the rotating rod provided by the present invention drives the rotating disk to rotate, causing the screening rack to move upward; Figure 13 The present invention provides a screening rack driving the baffle and the gear plate to move upward, so that the gear drives the outlet pipe to rotate state schematic diagram; Figure 14 This is a schematic diagram of the method for recycling lithium from waste carbon blocks provided by the present invention.

[0018] Description of Figure Numbers: 1. Combustion furnace; 2. Mixing mechanism; 21. Mixing box; 22. Rotating rod; 23. Mixing paddle; 24. Mixing frame; 25. Mounting base; 26. Driving motor; 27. Feeding pipe; 3. Intermittent jet mechanism; 31. Mounting plate; 32. Bracket; 33. Cylinder; 34. Rotating shaft; 35. Boss; 36. Piston; 37. Movable rod; 38. Spring; 39. Rotating wheel; 4. Adjustment mechanism; 41. Sliding frame; 42. Baffle; 43. Gear plate; 44. Rotating seat; 45. Exhaust pipe; 46. Gear; 47. Injection head; 5. Inlet pipe; 6. Hose; 7. Mounting bracket; 8. Screening mechanism; 81. Rotating disk; 82. Convex plate; 83. Screening frame; 84. Connecting frame; 85. Moving wheel; 9. Gas sensor; 10. Pipeline; 11. Feed pipe; 12. Exhaust pipe; 13. Base; 14. Mounting bracket; 15. Ring pipe; 16. Nozzle.

[0019] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0021] The present invention provides a device and method for recycling waste carbon blocks into lithium.

[0022] First embodiment: See also Figures 1 to 7 and Figure 9 , a waste carbon block lithium extraction resource recovery device, comprising a combustion furnace 1, a mixing mechanism 2, an intermittent jet mechanism 3 and a regulating mechanism 4; The mixing mechanism 2 includes a mixing box 21 disposed on the top of the combustion furnace 1. A rotating rod 22 is vertically connected to the inner side of the mixing box 21. Three mixing paddles 23 are fixed on the surface of the rotating rod 22. A mixing frame 24 is fixed on the surface of the rotating rod 22 and located at the bottom of the mixing paddles 23. A mounting base 25 is provided on the top of the mixing box 21. A driving motor 26 for driving the rotating rod 22 is provided on the top of the mounting base 25. Two feeding pipes 27 are connected to the top of the mixing box 21. Please combine Figure 9 : Starting the drive motor 26, the drive motor 26 rotates to drive the rotating rod 22 to rotate, and the rotating rod 22 rotates to drive the mixing paddle 23 and the mixing frame 24 to rotate, thereby mixing the carbon slag powder and the alkaline compound by mechanical stirring; Preferably, the bottom of the mixing box 21 is connected to four discharge pipes, and a solenoid valve is provided on the surface. The four discharge pipes are connected to the combustion furnace 1 through flanges, and the bottom of the inner wall of the mixing box 21 is an inverted trapezoid; The intermittent jet mechanism 3 includes a mounting plate 31, a bracket 32 ​​and an air cylinder 33. The mounting plate 31 is fixed to the bottom of the mixing box 21 through a plurality of brackets 32. The inner side of the mounting plate 31 is vertically rotatably connected to a rotating shaft 34. The top end of the rotating shaft 34 is fixedly connected to the bottom end of the rotating rod 22. The keyway of the rotating shaft 34 is connected to a convex plate 35 at a position away from the center of the circle. The air cylinders 33 are distributed in a circular array with the rotating shaft 34 as the center of the circle. The inner walls of the four air cylinders 33 are slidably connected to pistons 36 and movable rods 37. The four movable rods 37 are respectively fixedly connected to the four pistons 36. The surfaces of the four movable rods 37 are slidably connected to the inner wall of the air cylinder 33. The surfaces of the four movable rods 37 and the inner side of the mounting plate 31 are all provided with springs 38. The inner sides of the four movable rods 37 are rotatably connected to rotating wheels 39, and the rotating wheels 39 are close to the peripheral side of the convex plate 35. Please combine Figures 3 to 6When the rotating rod 22 rotates, the rotating shaft 34 is driven to rotate, and the rotation of the rotating shaft 34 drives the convex plate 35 to rotate. During the rotation of the convex plate 35, the four rotating wheels 39 are squeezed in turn, so that the four movable rods 37 drive the four pistons 36 to slide in the air cylinder 33 in turn. Through the setting of the spring 38, when the raised position of the convex plate 35 is away from the rotating wheel 39, the spring 38 is reset to drive the movable rod 37 to move inward, so that the rotating wheel 39 is close to the surface of the convex plate 35. The piston 36 is reset by the movement of the movable rod 37. When the rotating shaft 34 continues to drive the convex plate 35 to rotate, the four air cylinders 33 are caused to circulate and spray gas in turn through the top hose 6. When used in conjunction with the regulating mechanism 4, the effect of intermittent jetting in different directions is achieved, and the ejected gas is used to mix the carbon slag powder and the alkaline compound; The regulating mechanism 4 is slidably connected to the inner side of the mixing box 21 and is used to adjust the injection angle of the gas; The four gas cylinders 33 are connected to an air inlet pipe 5 on one side thereof, and are connected to a hose 6 on the top and bottom of the four gas cylinders 33. A mounting bracket 7 is fixed to the side surface of the four gas cylinders 33, and the mounting bracket 7 is fixedly connected to the top of the combustion furnace 1 by bolts. Preferably, valves are provided on the surfaces of the air inlet pipe 5 and the hose 6; A plurality of mounting brackets 14 are fixedly provided on the top of the inner wall of the combustion furnace 1. An annular tube 15 is fixedly provided on the inner side of the mounting brackets 14. The inner side of the annular tube 15 is connected to four nozzles 16. Please combine Figure 7 : When the valve of the bottom hose 6 is opened, the cam 35 is continuously driven to rotate by the rotating shaft 34, so that the gas is injected into the combustion furnace 1 through the bottom hose 6, the annular tube 15 and the nozzle 16. The four nozzles 16 are distributed in a circular array, which can quickly disperse the oxygen.

[0023] In this embodiment, unlike the existing waste carbon block lithium resource recovery equipment, this equipment, when mixing and roasting the carbon slag powder and the alkaline compound, drives the mixing paddle 23 and the mixing frame 24 to rotate by rotating the rotating rod 22, and physically stirs and mixes the carbon slag powder and the alkaline compound. When the rotating rod 22 rotates, it drives the bottom rotating shaft 34 to rotate. The rotation of the rotating shaft 34 drives the convex plate 35 to squeeze the four rotating wheels 39 in turn, so that the movable rod 37 drives the piston 36 to slide in the air cylinder 33, squeezing the gas outward. Through the setting of the spring 38, when the raised position of the convex plate 35 is far away When leaving the rotating wheel 39, the spring 38 extends to drive the movable rod 37 and the piston 36 to reset, thereby drawing the gas into the air cylinder 33, and continuously rotating through the convex disc 35. The four air cylinders 33 circulate and spray the gas in turn through the top hose 6. When used in conjunction with the adjustment mechanism 4, the effect of intermittent jetting in different directions is achieved, and the ejected gas is used to mix the carbon slag powder and the alkaline compound. After the two are combined with each other, the carbon slag powder and the alkaline compound can be fully mixed to avoid insufficient contact at the reaction interface, improve the recovery effect of lithium extraction from waste carbon blocks, and reduce the volatilization of harmful gases.

[0024] Second embodiment: See also Figure 1 、 Figures 8 to 13 The surface of the rotating rod 22 is fixedly provided with a screening mechanism 8, and the screening mechanism 8 includes a rotating disk 81 fixedly provided on the surface of the rotating rod 22, and a convex plate 82 is fixedly provided on the top of the rotating disk 81. The surface of the rotating rod 22 is slidably connected to a screening frame 83, and the bottom of the screening frame 83 is fixedly provided with three connecting frames 84. The inner sides of the three connecting frames 84 are rotatably connected to moving wheels 85, and the bottoms of the three moving wheels 85 are in contact with the top of the rotating disk 81; Please combine Figure 8 and Figure 12 : When the rotating rod 22 rotates, it will also drive the rotating disk 81, and the rotation of the rotating disk 81 will drive the top convex plate 82 to rotate. When the convex plate 82 contacts the moving wheel 85, the moving wheel 85 will be pushed upward, and the screening rack 83 will slide upward on the surface of the rotating rod 22 under the action of the connecting frame 84 through the moving wheel 85. When the convex plate 82 is out of contact with the moving wheel 85, the screening rack 83 slides downward on the surface of the rotating rod 22 under the action of gravity, and the rotating disk 81 continues to rotate, so that the screening rack 83 moves back and forth, thereby screening the carbon slag powder and alkaline compounds.

[0025] The regulating mechanism 4 includes four sliding frames 41 slidably connected to the inner side of the mixing box 21, and the four sliding frames 41 are distributed in a circular array with the rotating rod 22 as the center. A baffle 42 is fixed on the separated side of the four sliding frames 41, and a gear plate 43 is fixed on the opposite side of the four baffles 42. Four rotating seats 44 are fixed on the inner wall of the mixing box 21 in a circular array. The inner sides of the four rotating seats 44 are rotatably connected to the air outlet pipes 45. The surfaces of the four air outlet pipes 45 are fixed with gears 46, which mesh with the gear plates 43. The surfaces of the four air outlet pipes 45 are connected to the nozzles 47. The opposite sides of the four sliding racks 41 are fixedly connected to the peripheral side of the screening rack 83, and the output ends of the four hoses 6 are respectively connected to the four air outlet pipes 45; Please combine Figure 10 、 Figure 11 and Figure 13 When the screening rack 83 moves upward, it simultaneously drives the four sliding racks 41 to slide upward on the inner side of the mixing box 21. The movement of the sliding rack 41 drives the baffle 42 and the gear plate 43 to move upward. The upward movement of the gear plate 43 drives the gear 46 to rotate. The rotation of the gear 46 drives the outlet pipe 45 and the nozzle 47 to rotate, thereby adjusting the angle of the nozzle 47. When the screening rack 83 continues to move up and down, it drives the gear plate 43 to move up and down through the sliding rack 41 and the baffle 42, thereby causing the gear 46 to drive the outlet pipe 45 and the nozzle 47 to swing back and forth. A gas sensor 9 is fixedly provided on the top of the combustion furnace 1. The front side of the gas sensor 9 is connected to a pipe 10. The bottom end of the pipe 10 is connected to the combustion furnace 1. The top of the combustion furnace 1 is connected to a feeding pipe 11. Please combine Figure 1 : A gas sensor 9 is set to detect the gas generated during roasting. When toxic gases such as HF and SiF4 are detected, an alkaline compound is added to the combustion furnace 1 using a feeding pipe 11. During the roasting process, the alkaline compound reacts with the fluoride to convert it into stable calcium oxide, reducing the emission of HF and SiF4 gases and lowering the pressure of subsequent tail gas treatment.

[0026] The right side of the combustion furnace 1 is connected to a smoke exhaust pipe 12, and a base 13 is fixed to the bottom of the combustion furnace 1; Preferably, the smoke exhaust pipe 12 is connected to a tail gas treatment unit for purifying the combustion tail gas.

[0027] In this embodiment, when the rotating rod 22 rotates to drive the mixing paddle 23 and the mixing frame 24 to rotate, it will also drive the rotating disk 81 to rotate, and the rotating disk 81 will continue to drive the convex plate 82 to rotate, and under the action of the moving wheel 85 and the connecting frame 84, the screening frame 83 will be driven to move up and down reciprocatingly, thereby screening the carbon slag powder and alkaline compounds. When the screening frame 83 moves up and down reciprocatingly, it will drive the gear plate 43 up and down through the sliding frame 41 and the baffle 42, so that the gear 46 drives the outlet pipe 45 and the nozzle 47 to swing up and down, so that the gas is ejected from different angles, thereby improving the mixing effect of the carbon slag powder and the alkaline compound, reducing the volatilization of harmful gases during roasting, promoting the conversion of lithium, and improving the dissolution rate of lithium in the subsequent acid leaching step.

[0028] Third embodiment: See also Figure 14 A method for recycling waste carbon blocks by extracting lithium as a resource comprises the following steps: S1. Preprocessing: Crushing waste carbon blocks from electrolytic aluminum to obtain carbon slag powder; Preferably, the particle size of the carbon slag powder after crushing is 50-200 mesh; S2, roasting treatment: The pretreated carbon slag powder is uniformly mixed with the alkaline compound according to a mass ratio and roasted; Preferably, the alkaline compound is selected from at least one of calcium hydroxide, calcium oxide, and aluminum hydroxide, preferably a combination of calcium hydroxide and calcium oxide, with a mass ratio of 1:2 to 1:20. Calcium hydroxide and calcium oxide are used to solidify harmful substances such as fluorine and cyanide. The roasting process solidifies harmful substances such as fluorine and cyanide into stable calcium fluoride and harmless gases (CO2, N2) through chemical conversion and high-temperature decomposition. The final product is mainly composed of substances such as CaF2, carbonates, aluminum oxide, unreacted carbon particles, and inert residues; The calcination temperature is 200-1000°C, the calcination time is 2-6 hours, and the heating rate is 3-15°C / min; S3, acid leaching reaction: The roasted product is crushed and mixed with sulfuric acid solution in a solid-liquid ratio, and leaching reaction is carried out in a constant temperature water bath, and solid-liquid separation is performed to obtain a leaching solution and a leaching residue; Preferably, the concentration of sulfuric acid solution is 60-98wt%, the acid leaching reaction temperature is 70-95°C, the reaction time is 0.5-4.5 hours, the stirring rate is 100-450rpm, and the leaching solution mainly contains Li + 、Al 3+ 、Fe 3+ , Ca 2+ etc. The primary leaching residue is mainly composed of inert substances such as CaF2, CaSO4, silicate, SiO2, etc. S4, purification treatment: Calcium oxide is added to the leaching solution in sequence to adjust the pH, oxalic acid is added for deep purification, and a purified liquid and purified residue are obtained after filtration. The purified residue is washed with sulfuric acid and then added to the pickling solution for recycling. Sodium carbonate is added to the purified liquid for lithium precipitation reaction to obtain a lithium carbonate product; Preferably, calcium oxide is used to adjust the pH to 3-7, the amount of oxalic acid added is 1-8 times the molar amount of calcium ions in the solution, the reaction temperature is 30-75°C, the reaction time is 20-80 minutes, and calcium oxide is used to adjust the pH to Fe 3 、Al 3+ etc. to precipitate impurities, oxalic acid and Ca 2+ Calcium oxalate precipitate is formed; The concentration of the solution for pickling with sulfuric acid is 60-98wt%, the amount of sodium carbonate added is 1.05-5 times the molar amount of lithium ions, the lithium precipitation reaction temperature is 30-90°C, the reaction time is 1-4 hours, the concentration of the solution for pickling with sulfuric acid is 60-98wt%, and the purified solution is subjected to lithium precipitation with sodium carbonate to prepare lithium carbonate; S5. First leaching residue treatment: The first leaching residue is mixed with a nitric acid-aluminum nitrate composite acid solution in a solid-liquid ratio, and a leaching reaction is carried out in a constant temperature water bath. After the reaction, disodium ethylenediaminetetraacetic acid is added for complexation and impurity removal. After filtering, ammonia water is added to the filtrate to adjust the pH value to 3 to 7, and aluminum fluoride product is precipitated. The residual residue can be used as fuel or building material after washing with water; Preferably, the nitric acid concentration in the nitric acid-aluminum nitrate composite acid solution is 30-98wt%, and the aluminum nitrate concentration is 20-95wt%, generating an acidic solution mainly containing H3AlF6 and Ca(NO3)2. The amount of disodium ethylenediaminetetraacetic acid added is 1.1-10 times the molar amount of the metal impurities. The complexation reaction temperature is 30-75°C. The complexation removes impurities such as Fe 3+ A soluble complex is generated, and the pH is adjusted to 3-7 with ammonia water and precipitated with H3AlF6 to produce aluminum fluoride products. The residual slag mainly consists of unreacted carbon, CaSO4, SiO4 and other substances, which can be used as fuel and building materials after washing.

[0029] In this embodiment, compared with the existing waste carbon block lithium resource recovery method, the lithium recovery efficiency is significantly improved, fluorine / cyanide is efficiently solidified, and F is achieved through CaO / Ca (OH)2 in the roasting stage. - 、CN - Stabilization; lithium selective leaching, acid leaching optimization pH control Li2SO4 dissolution, avoid Al 3+ Excessive dissolution, directional synthesis of aluminum fluoride, separation of Al by acid decomposition-complexation-precipitation three-step method 3+It can remove impurities and precisely control the crystallization conditions of AlF3, simultaneously realize the high-value recovery of aluminum fluoride and lithium carbonate, and the resource utilization of waste slag, and form a "lithium-fluorine-aluminum-slag" full-chain recovery system, which has both technological advancement and economic feasibility, and provides an innovative solution for the comprehensive treatment of waste carbon blocks of electrolytic aluminum.

[0030] Please refer to the Figures 1 to 14 The working principle of the waste carbon block lithium resource recovery equipment and method provided by the present invention is as follows: Step S1: crushing waste carbon blocks from electrolytic aluminum to obtain carbon slag powder, and then slowly adding the carbon slag powder and alkaline compound into the mixing box 21 in proportion through two feeding pipes 27; When the carbon slag powder and the alkaline compound are added, the drive motor 26 is started, and the rotation of the drive motor 26 drives the rotation rod 22 to rotate, and the rotation of the rotation rod 22 drives the mixing paddle 23 and the mixing frame 24 to rotate, thereby mixing the carbon slag powder and the alkaline compound by mechanical stirring; In step S2, the rotating rod 22 rotates and simultaneously drives the rotating shaft 34 to rotate. The rotation of the rotating shaft 34 drives the cam 35 to rotate. During the rotation of the cam 35, the four rotating wheels 39 are squeezed in turn, so that the four movable rods 37 drive the four pistons 36 to slide in the air cylinder 33 in turn. Due to the setting of the spring 38, when the raised position of the cam 35 is away from the rotating wheel 39, the spring 38 resets and drives the movable rod 37 to move inward, so that the rotating wheel 39 is close to the surface of the cam 35. The piston 36 is reset by the movement of the movable rod 37. When the rotating shaft 34 continues to drive the cam 35 to rotate, the four air cylinders 33 circulate and spray gas in turn through the top hose 6. When used in conjunction with the regulating mechanism 4, intermittent gas is sprayed in different directions, and the sprayed gas is used to mix the carbon slag powder and the alkaline compound. Step S3: When the rotating rod 22 rotates, it simultaneously drives the rotating disk 81. The rotation of the rotating disk 81 drives the top protruding plate 82 to rotate. When the protruding plate 82 contacts the moving wheel 85, the moving wheel 85 is lifted upward. The moving wheel 85, under the action of the connecting frame 84, causes the screening rack 83 to slide upward on the surface of the rotating rod 22. When the protruding plate 82 and the moving wheel 85 are out of contact, the screening rack 83 slides downward on the surface of the rotating rod 22 under the action of gravity. The rotating disk 81 continues to rotate, causing the screening rack 83 to reciprocate up and down, thereby screening the carbon residue powder and alkaline compounds. In step S4, when the screening rack 83 moves upward, it simultaneously drives the four sliding racks 41 to slide upward inside the mixing box 21. The movement of the sliding rack 41 drives the baffle 42 and the gear plate 43 to move upward. The upward movement of the gear plate 43 drives the gear 46 to rotate. The rotation of the gear 46 drives the air outlet pipe 45 and the air jet head 47 to rotate, thereby adjusting the angle of the air jet head 47. When the screening rack 83 continues to move up and down, it drives the gear plate 43 to move up and down through the sliding rack 41 and the baffle 42, thereby causing the gear 46 to drive the air outlet pipe 45 and the air jet head 47 to swing back and forth, thereby adjusting the direction of the air jet. Step S5: When the gas sensor 9 detects toxic gases such as HF and SiF4, an alkaline compound is added to the combustion furnace 1 through the feeding pipe 11. During the roasting process, the alkaline compound reacts with the fluoride to convert it into stable calcium oxide, thereby reducing the emission of HF and SiF4 gases and lowering the pressure of subsequent tail gas treatment. Step S6, crushing the roasted product and mixing it with sulfuric acid solution in a solid-liquid ratio, performing a leaching reaction in a constant temperature water bath, and separating the solid and liquid to obtain a leaching solution and a leaching residue; Calcium oxide is added to the leaching solution in sequence to adjust the pH, oxalic acid is added for deep purification, and a purified liquid and purified residue are obtained after filtration. The purified residue is washed with sulfuric acid and then added to the pickling solution for recycling. Sodium carbonate is added to the purified liquid for lithium precipitation reaction to obtain a lithium carbonate product; The first leaching residue is mixed with a nitric acid-aluminum nitrate composite acid solution in a solid-liquid ratio, and a leaching reaction is carried out in a constant temperature water bath. After the reaction, disodium ethylenediaminetetraacetic acid is added for complexation and impurity removal. After filtration, ammonia water is added to the filtrate to adjust the pH value to 3 to 7, and aluminum fluoride product is precipitated. The residual residue can be used as fuel or building material after washing with water.

[0031] 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 by using the contents of the present invention description and drawings under the concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A waste carbon block lithium extraction resource recovery device, characterized in that: It includes a combustion furnace, a mixing mechanism, an intermittent jet mechanism and a regulating mechanism; The mixing mechanism includes a mixing box arranged on the top of the combustion furnace, the inner side of the mixing box is vertically connected to a rotating rod, the surface of the rotating rod is fixed with three mixing paddles, and a mixing frame is fixed on the surface of the rotating rod and located at the bottom of the mixing paddles; The intermittent jet mechanism includes a mounting plate, a bracket and an air cylinder, the mounting plate is fixedly mounted on the bottom of the mixing box through a plurality of brackets, the inner side of the mounting plate is vertically rotatably connected to a rotating shaft, the top end of the rotating shaft is fixedly connected to the bottom end of the rotating rod, the keyway of the rotating shaft away from the center of the circle is connected to a convex plate, the air cylinder is distributed in a circular array with the rotating shaft as the center of the circle, the inner walls of the four air cylinders are slidably connected to pistons and movable rods, the four movable rods are respectively fixedly connected to the four pistons, the surfaces of the four movable rods are slidably connected to the inner wall of the air cylinder, the surfaces of the four movable rods and the inner side of the mounting plate are all provided with springs, the inner sides of the four movable rods are rotatably connected to rotating wheels, and the rotating wheels are tightly against the peripheral side surfaces of the convex plate; The regulating mechanism is slidably connected to the inner side of the mixing box and is used for adjusting the injection angle of the gas.

2. The waste carbon block lithium extraction and resource recovery equipment according to claim 1 is characterized in that: The four gas cylinders are connected to an air inlet pipe on one side thereof, and are connected to a hose at the top and bottom thereof. A mounting bracket is fixedly provided on the circumferential side of the four gas cylinders, and the mounting bracket is fixedly connected to the top of the combustion furnace by bolts. A plurality of mounting brackets are fixedly provided on the top of the inner wall of the combustion furnace, an annular tube is fixedly provided on the inner side of the plurality of mounting brackets, and four nozzles are connected to the inner side of the annular tube.

3. The waste carbon block lithium extraction and resource recovery equipment according to claim 1 is characterized in that: A mounting seat is provided on the top of the mixing box, a driving motor for driving the rotating rod to rotate is provided on the top of the mounting seat, and two feeding pipes are connected to the top of the mixing box.

4. The waste carbon block lithium extraction and resource recovery equipment according to claim 2 is characterized in that: A screening mechanism is fixedly provided on the surface of the rotating rod, and the screening mechanism includes a rotating disk fixedly provided on the surface of the rotating rod, a convex plate is fixedly provided on the top of the rotating disk, a screening rack is slidably connected to the surface of the rotating rod, and three connecting racks are fixedly provided on the bottom of the screening rack, and the inner sides of the three connecting racks are rotatably connected to moving wheels, and the bottoms of the three moving wheels are in contact with the top of the rotating disk.

5. The waste carbon block lithium extraction and resource recovery equipment according to claim 4 is characterized in that: The adjusting mechanism includes four sliding frames slidably connected to the inner side of the mixing box, the four sliding frames are distributed in a circular array with the rotating rod as the center, baffles are fixed on the separated sides of the four sliding frames, gear plates are fixed on the opposite sides of the four baffles, four rotating seats are fixed in a circular array on the inner wall of the mixing box, the inner sides of the four rotating seats are rotatably connected to the air outlet pipes, gears are fixed on the surfaces of the four air outlet pipes, the gears are meshed with the gear plates, and the surfaces of the four air outlet pipes are connected to the nozzles.

6. The waste carbon block lithium extraction and resource recovery equipment according to claim 5 is characterized in that: One side opposite to the four sliding racks is fixedly connected to the peripheral side surface of the screening rack, and the output ends of the four hoses are respectively communicated with four air outlet pipes.

7. The waste carbon block lithium extraction and resource recovery equipment according to claim 1 is characterized in that: A gas sensor is fixedly provided on the top of the combustion furnace. The front side of the gas sensor is connected with a pipeline. The bottom end of the pipeline is connected with the combustion furnace. The top of the combustion furnace is connected with a feeding pipe.

8. The waste carbon block lithium extraction and resource recovery equipment according to claim 1 is characterized in that: The right side of the combustion furnace is connected with a smoke exhaust pipe, and the bottom of the combustion furnace is fixedly provided with a base.

9. A method for recycling waste carbon blocks by extracting lithium as a resource, characterized in that: The method comprises the waste carbon block lithium extraction and resource recovery equipment according to any one of claims 1 to 8 and the following steps: S1. Preprocessing: Crushing waste carbon blocks from electrolytic aluminum to obtain carbon slag powder; S2, roasting treatment: The pretreated carbon slag powder is uniformly mixed with the alkaline compound according to a mass ratio and roasted; S3, acid leaching reaction: The roasted product is crushed and mixed with sulfuric acid solution in a solid-liquid ratio, and leaching reaction is carried out in a constant temperature water bath, and solid-liquid separation is performed to obtain a leaching solution and a leaching residue; S4, purification treatment: Calcium oxide is added to the leaching solution in sequence to adjust the pH, oxalic acid is added for deep purification, and a purified liquid and purified residue are obtained after filtration. The purified residue is washed with sulfuric acid and then added to the pickling solution for recycling. Sodium carbonate is added to the purified liquid for lithium precipitation reaction to obtain a lithium carbonate product; S5. First leaching residue treatment: The first leaching residue is mixed with a nitric acid-aluminum nitrate composite acid solution in a solid-liquid ratio, and a leaching reaction is carried out in a constant temperature water bath. After the reaction, disodium ethylenediaminetetraacetic acid is added for complexation and impurity removal. After filtration, ammonia water is added to the filtrate to adjust the pH value to 3 to 7, and aluminum fluoride product is precipitated. The residual residue can be used as fuel or building material after washing with water.

Images