Device and method for extracting lithium from overhaul slag based on solid waste recycling

Abstract

The invention provides an overhaul slag lithium extraction device and method based on solid waste recycling, and relates to the technical field of solid waste treatment, the overhaul slag lithium extraction device comprises an extraction tank, a heating seat, a side frame, a mixing tank, a driving mechanism and a mixing mechanism; the extraction tank is mounted on the inner wall of the heating seat in a penetrating manner, the side frame is fixedly arranged on the side wall of the extraction tank, and the mixing tank is mounted in the side frame in a penetrating manner; a first top cover is hermetically mounted at the top of the extraction tank, a mounting frame is fixedly arranged at the top of the first top cover, and the driving mechanism comprises a supporting seat, a motor and a driving gear. According to the scheme, sulfuric acid and phosphoric acid are evenly mixed in a mixing tank and then added into an extraction tank to react with transformation slag, the follow-up leaching effect is optimized by regulating and controlling the acid liquor state in advance, acid is mixed in the mixing tank in advance, heat can be evenly dispersed through stirring, and the mixture is added into the extraction tank after the system temperature is reduced to the normal temperature or the process set temperature; it is guaranteed that the leaching process is conducted at the stable temperature, and it can be guaranteed that workers work in a safe environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of solid waste treatment, and in particular to a device and method for extracting lithium from overhaul slag based on solid waste resource utilization. BACKGROUND

[0002] Electrolytic aluminum overhaul slag is a solid waste removed from the tank during the overhaul of production equipment reaching the service life in the electrolytic aluminum industry, which is one of the typical hazardous wastes in the electrolytic aluminum industry and needs to be treated and disposed in strict accordance with environmental protection standards.

[0003] Although electrolytic aluminum overhaul slag belongs to smelting slag, it is listed as hazardous waste due to the high toxicity of cyanide and high value of lithium and fluorine. The traditional disposal method is landfilling, which causes resource waste and environmental pollution. Therefore, it is necessary to harmless treatment and high value recovery of valuable elements of electrolytic aluminum overhaul slag, especially through specific roasting transformation and acid leaching process to realize directional separation and productization of lithium and fluorine elements.

[0004] In the prior art, when extracting lithium from electrolytic aluminum overhaul slag by acid leaching, sulfuric acid combined with phosphoric acid is used to extract lithium elements from the transformed slag. In the extraction process, the traditional method is to directly put into the transformed slag, which can easily cause violent reaction and poor safety, and is not convenient for users to operate extraction in a safe environment.

[0005] Therefore, it is necessary to provide a device and method for extracting lithium from overhaul slag based on solid waste resource utilization to solve the above technical problems. SUMMARY

[0006] The present application provides a device and method for extracting lithium from overhaul slag based on solid waste resource utilization, which solves the problem of violent reaction with transformed slag and acid leaching danger in traditional acid leaching in related technologies.

[0007] To solve the above technical problems, the present application provides a device for extracting lithium from overhaul slag based on solid waste resource utilization, which comprises an extraction tank, a heating seat, a side frame, a mixing tank, a driving mechanism and a mixing mechanism.

[0008] The extraction tank is installed through the inner wall of the heating seat, the side frame is fixed to the side wall of the extraction tank, and the mixing tank is installed through the inside of the side frame.

[0009] The first top cover is top-fixed with a mounting frame, the driving mechanism comprises a support seat, a motor and a driving gear, the support seat is top-fixed on the upper surface of the first top cover and located inside the mounting frame, the motor is installed on the upper surface of the support seat, the driving gear is key-groove connected with the output shaft of the motor, the driving gear is meshingly connected with a driven gear on one side, the driven gear is key-groove connected with a middle shaft at the shaft center, the mounting frame is top-fixed with a limiting plate, the middle shaft is key-groove connected with a first ratchet at the top end, the first ratchet is meshingly connected with a first ratchet sleeve outside the wall, and the first ratchet sleeve is bottom-fixed with a driving pulley.

[0010] The second top cover is top-sealedly installed on the top of the mixing tank, the mixing mechanism comprises a driven pulley and a first belt, the driven pulley is rotationally connected to the top end of the second top cover, the first belt is sleeved on the outer wall of the driving pulley and the driven pulley, the mixing rod and a rotating ring are key-groove connected at the shaft center of the driven pulley and located inside the mixing tank, the rotating ring is fixed with three arc-shaped racks outside the wall, two mounting plates are fixed inside the mixing tank, a rotating gear is installed above each of the two mounting plates, and a hose is installed on the top of each of the two rotating gears.

[0011] Preferably, the first ratchet is rotationally connected with the limiting plate at the shaft center, and the driving pulley is rotationally connected with the mounting frame.

[0012] Preferably, the shaft centers of the first ratchet sleeve and the driving pulley are designed as hollow and do not contact with the middle shaft, and the middle shaft penetrates through the shaft centers of the driving pulley and the first ratchet sleeve.

[0013] Preferably, the three arc-shaped racks are equidistantly and annularly distributed about the shaft center of the rotating ring, and the arc-shaped racks and the rotating gears are meshingly engaged with each other.

[0014] Preferably, a sleeve is installed inside the mounting plate, a "T"-shaped positioning rod is rotationally installed inside the sleeve, a torsion spring is sleeved on the outer wall of the positioning rod and located inside the sleeve, and the shaft center of the rotating gear is key-groove connected with the shaft center of the positioning rod.

[0015] Preferably, it further comprises a distributing mechanism.

[0016] The middle shaft is key-groove connected with a second ratchet at the bottom end, the second ratchet is sleeved with a second ratchet sleeve outside the wall, and the second ratchet sleeve is bottom-fixed with a first pulley.

[0017] The material distribution mechanism comprises a second pulley rotatably mounted on the upper surface of the first top cover, the outer wall of the first pulley and the second pulley is sleeved with a second belt, the shaft center of the first pulley is connected with a stirring rod in the key groove inside the extraction tank, the shaft center of the second pulley is connected with a rotating rod in the key groove on one side of the stirring rod, the outer wall of the rotating rod is fixedly provided with a material distribution disc, the side wall of the material distribution disc is fixedly provided with a discharging frame, and the side wall of the mixing tank is fixedly provided with a liquid outlet pipe.

[0018] Preferably, the outer wall of the stirring rod and the rotating rod is rotatably connected with the first top cover, and the liquid outlet pipe penetrates into the extraction tank and extends to the upper surface of the material distribution disc.

[0019] Preferably, an "L"-shaped sampling pipe is mounted inside the extraction tank and below the liquid outlet pipe, a rotating paddle is fixedly arranged at the bottom end of the rotating rod, a feeding pipe is mounted on the side wall above the extraction tank, and a discharging pipe is mounted at the bottom end of the extraction tank.

[0020] The method for extracting lithium from overhauled slag based on solid waste resource utilization comprises the following steps:

[0021] S1: pretreatment;

[0022] The overhauled slag is crushed to 100-200 mesh by a jaw crusher, and uniform carbon residue powder is obtained by screening;

[0023] Primary roasting: oxygen or inert gas is introduced into a tubular furnace, the temperature is raised to 500-800 DEG C at a rate of 8-12 DEG C / min, and the temperature is maintained for 1.5-3 h, the material after roasting is light gray, the fluorine and lithium are basically not lost, the removal of carbon is promoted, and the cyanide decomposition rate is > 99.8%;

[0024] Secondary roasting: the roasted slag is mixed with calcium hydroxide and calcium sulfate at a mass ratio of 15:2:1, and is roasted in a muffle furnace at 400-900 DEG C for 0.5-2 h to form soluble lithium salt and CaF2;

[0025] S2: acid leaching to extract lithium;

[0026] The transformed slag is mixed with 60-98 wt% sulfuric acid and 30-50 wt% phosphoric acid, and after stirring and leaching at 75-90 DEG C for 2 h, filtration is performed for detection, and this step needs to be performed in the extraction tank during the acid leaching to extract lithium;

[0027] S3: lithium precipitation and purification;

[0028] The leaching solution is added with CaO suspension to adjust the pH to 12, Al and Fe impurities are removed by filtration, 1-1.5 times the stoichiometric amount of trisodium phosphate is added, and the mixture is reacted at 60-80 DEG C for 1 h, then washed with 90 DEG C hot water for 3 times after aging, and dried to obtain battery-grade lithium phosphate;

[0029] S4: aluminum fluoride preparation;

[0030] After the acid leaching residue is cleaned with 0.3-0.8 mol / L hydrochloric acid, it is mixed with Al2O3 at an Al / F molar ratio of 1:3 and then smelted in a muffle furnace at 600-900℃ for 1 hour to obtain aluminum fluoride.

[0031] Compared with related technologies, the lithium extraction device and method based on solid waste resource utilization provided by this invention have the following beneficial effects:

[0032] In the process of lithium extraction by leaching, sulfuric acid and phosphoric acid are first mixed evenly in a mixing tank, and then added to the extraction tank to react with the transformation residue. By adjusting the acid state in advance, the subsequent leaching effect is optimized. Stirring is used to make the two acids form a uniform concentration mixture system. After being added to the extraction tank, it can be evenly contacted with the transformation residue, ensuring that every residue particle is in the optimal reaction acid concentration environment and reducing local imbalance problems.

[0033] Pre-mixing the acid in the mixing tank allows for even heat distribution through stirring. The acid is then added to the extraction tank after the system temperature has dropped to room temperature or the process set temperature, ensuring that the leaching process is carried out at a stable temperature and that workers can work in a safe environment. Attached Figure Description

[0034] 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.

[0035] Figure 1 The optimal structural schematic diagram provided for this invention;

[0036] Figure 2 for Figure 1 The diagram shows a cross-sectional view of the extraction tank and the mixing tank.

[0037] Figure 3 for Figure 2 The diagram shows the structure viewed from below.

[0038] Figure 4 for Figure 1 The diagram shows a detailed structural schematic of the drive mechanism.

[0039] Figure 5 for Figure 4 The enlarged structural diagram at point A is shown below;

[0040] Figure 6 for Figure 5 The schematic diagram shows the cross-sectional structure of the mounting bracket, the first ratchet sleeve, and the drive pulley.

[0041] Figure 7 is a bottom structure schematic view shown in the figure; Figure 6 is a bottom structure schematic view shown in the figure;

[0042] Figure 8 is a detailed structure schematic view of the mixing mechanism provided by the application;

[0043] Figure 9 is a bottom structure schematic view shown in the figure; Figure 8 is an enlarged structure schematic view at B shown in the figure;

[0044] Figure 10 Figure 8 is a sectional structure schematic view of the mounting plate and sleeve shown in the figure;

[0045] Figure 11 is a schematic view of the working state of the mixing mechanism provided by the application, wherein (a) is a schematic view of the initial working state of the two hoses, (b) is a schematic view of the working state of controlling the rotation of one hose when the arc-shaped rack rotates, and (c) is a schematic view of the working state of controlling the rotation of the other hose when the arc-shaped rack continues to rotate;

[0046] Figure 12 is a schematic view of the position distribution of the material distribution mechanism and the liquid outlet pipe provided by the application;

[0047] Figure 13 is a flow chart of the method for extracting lithium from overhauled slag based on solid waste resource;

[0048] Figure 14 is a lithium phosphate XRD pattern;

[0049] Figure 15 is an aluminum fluoride XRD pattern.

[0050] Explanation of reference numerals:

[0051] 1, extraction tank, 2, temperature raising seat, 3, first top cover;

[0052] 4, side frame, 5, mixing tank;

[0053] 6, mixing mechanism, 61, driven pulley, 62, first belt, 63, mixing rod, 64, swivel ring, 65, arc-shaped rack, 66, liquid outlet pipe, 67, mounting plate, 68, rotating gear, 69, hose, 610, sleeve, 611, positioning rod, 612, torsional spring;

[0054] 7, driving mechanism, 71, support seat, 72, motor, 73, driving gear, 74, driven gear, 75, middle shaft, 76, limiting plate, 77, first ratchet, 78, first ratchet sleeve, 79, driving pulley, 710, second ratchet, 711, second ratchet sleeve, 712, first pulley;

[0055] 8, distributing mechanism, 81, second pulley, 82, second belt, 83, stirring rod, 84, rotating rod, 85, distributing disc, 86, discharging frame, 87, rotating paddle;

[0056] 9, second top cover, 10, sampling tube;

[0057] 11, feeding pipe, 12, discharging pipe, 13, mounting frame. DETAILED DESCRIPTION

[0058] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0059] The present application provides a kind of based on solid waste resourceization's overhauling slag lithium extraction device and method.

[0060] First embodiment:

[0061] Please refer to Figures 1 to 11 A kind of based on solid waste resourceization's overhauling slag lithium extraction device, including extraction tank 1, temperature rising seat 2, side frame 4, mixing tank 5, drive mechanism 7 and mixing mechanism 6;

[0062] The extraction tank 1 is installed in the inner wall of the temperature rising seat 2 in a through manner, the side frame 4 is fixed to the side wall of the extraction tank 1, and the mixing tank 5 is installed in the inside of the side frame 4 in a through manner;

[0063] The first top cover 3 is sealingly installed on the top of the extraction tank 1, the mounting frame 13 is fixed to the top of the first top cover 3, the drive mechanism 7 includes a support seat 71, a motor 72 and a drive gear 73, the support seat 71 is fixed to the upper surface of the first top cover 3 and located inside the mounting frame 13, the motor 72 is installed on the upper surface of the support seat 71, the drive gear 73 is connected to the output shaft of the motor 72 in a key groove, the drive gear 73 is meshingly connected with a driven gear 74 on one side, the driven gear 74 is connected with a middle shaft 75 in a key groove at the shaft center, the mounting frame 13 is fixed with a limiting plate 76 on the top, the first ratchet wheel 77 is connected with the first ratchet sleeve 78 in a meshing manner on the outer wall, and the first ratchet sleeve 78 is fixed with a drive pulley 79 at the bottom.

[0064] The second top cover 9 is sealingly installed on the top of the mixing tank 5, the mixing mechanism 6 comprises a driven pulley 61 and a first belt 62, the driven pulley 61 is rotationally connected to the top end of the second top cover 9, the first belt 62 is sleeved on the outer wall of the driving pulley 79 and the driven pulley 61, the mixing rod 63 and the rotating ring 64 are connected to the key groove at the axis of the driven pulley 61 and inside the mixing tank 5, the three arc-shaped racks 65 are fixedly arranged on the outer wall of the rotating ring 64, the two mounting plates 67 are fixedly arranged on the inner wall of the mixing tank 5, the rotating gears 68 are installed above the two mounting plates 67, and the hoses 69 are installed on the top of the two rotating gears 68.

[0065] The first ratchet 77 is rotationally connected to the limiting plate 76 at the axis, and the driving pulley 79 is rotationally connected to the mounting frame 13.

[0066] The axes of the first ratchet sleeve 78 and the driving pulley 79 are designed to be hollow and not in contact with the middle shaft 75, and the middle shaft 75 penetrates the axes of the driving pulley 79 and the first ratchet sleeve 78.

[0067] The three arc-shaped racks 65 are equidistantly and annularly distributed about the axis of the rotating ring 64, and the arc-shaped racks 65 and the rotating gears 68 are in meshing relationship.

[0068] The sleeve 610 is installed inside the mounting plate 67, the "T"-shaped positioning rod 611 is rotationally installed inside the sleeve 610, the torsional spring 612 is sleeved on the outer wall of the positioning rod 611 and inside the sleeve 610, and the axis of the rotating gear 68 is in key groove connection with the axis of the positioning rod 611.

[0069] Please refer to Figure 4 and Figure 5 : The motor 72 can preferably be a three-phase asynchronous motor, and the user starts the motor 72 to control the driving gear 73 to mesh and drive the driven gear 74 to rotate, and the driven gear 74 can control the clockwise or counterclockwise rotation of the middle shaft 75, first, the clockwise rotation of the middle shaft 75 synchronously controls the clockwise rotation of the first ratchet 77, and when the first ratchet 77 rotates clockwise, it meshes and controls the first ratchet sleeve 78 to drive the driving pulley 79 to synchronously rotate clockwise.

[0070] Please refer to Figure 4 and Figure 8 : Therefore, the clockwise rotation of the driving pulley 79 drives and controls the first belt 62 to control the rotation of the driven pulley 61, and when the driven pulley 61 rotates, the rotating ring 64 and the mixing rod 63 can be controlled to rotate clockwise in the mixing tank 5.

[0071] Please refer to Figure 8 and Figure 9The user can install the sulfuric acid and phosphoric acid delivery devices on the outside of the two hoses 69 to deliver sulfuric acid and phosphoric acid into the mixing tank 5 through the two hoses 69.

[0072] Please refer to Figure 11 (a) in the initial state, the two hoses 69 are in a fixed-point delivery state of sulfuric acid and phosphoric acid;

[0073] Please refer to Figure 11 (b) when the rotating ring 64 rotates the arc-shaped rack 65, the rotating motion of the arc-shaped rack 65 engages the control rotating gear 68 to drive the hose 69 to rotate and form a fan-shaped motion trajectory to spray and deliver sulfuric acid or phosphoric acid, and at this time, the other rotating gear 68 cannot contact the arc-shaped rack 65 and thus still maintains a fixed-point delivery state;

[0074] Please refer to Figure 11 (c) as the rotating ring 64 continues to rotate, when the arc-shaped rack 65 and the rotating rotating gear 68 are separated, the rotating gear 68 is automatically reset due to the inability to form engagement, and when the upper arc-shaped rack 65 rotates to the position of the rotating gear 68, the control rotating gear 68 can be combined to drive the hose 69 to form a fan-shaped rotating trajectory to spray sulfuric acid or phosphoric acid.

[0075] It can be understood that, as shown in Figure 10 , the rotating gear 68 rotates in the sleeve 610 through the positioning rod 611, and in the rotating process, the torsional spring 612 is arranged, the upper part of the torsional spring 612 and the top of the sleeve 610 are limited, the bottom of the torsional spring 612 and the positioning rod 611 are limited, and when the rotating gear 68 is affected by the engagement force, the torsional spring 612 can be forced to twist, and when the rotating gear 68 loses the engagement force, the torsional spring 612 can control the rotating gear 68 to automatically reset to the initial state;

[0076] Preferably, the hoses 69 for delivering sulfuric acid and phosphoric acid can be made of corrosion-resistant fluoroplastic hoses 69.

[0077] Please refer to Figure 6 and Figure 7 : since the middle shaft 75 does not contact the first ratchet sleeve 78 and the drive pulley 79, the middle shaft 75 can independently control the rotation of the first ratchet 77 and will not cause interference with the first ratchet sleeve 78 and the drive pulley 79.

[0078] This embodiment:

[0079] In the process of leaching lithium, sulfuric acid is mixed with phosphoric acid in the mixing tank 5, and then added to the extraction tank 1 to react with the transformed slag. By adjusting the acid solution in advance, the subsequent leaching effect is optimized. With the help of stirring, the two acids form a mixed system with uniform concentration. After being added to the extraction tank 1, they can uniformly contact the transformed slag, ensuring that every part of the slag particle is in an optimal reaction acid concentration environment, reducing local imbalance problems.

[0080] In the mixing tank 5, the acid is mixed in advance, and the heat can be evenly dispersed by stirring. After the system temperature drops to room temperature or the process set temperature, the extraction tank 1 is added, ensuring that the leaching process is carried out at a stable temperature, which can ensure that the workers work in a safe environment.

[0081] For the acid leaching of lithium from electrolytic aluminum overhaul slag, the smelting slag is reasonably utilized, effectively avoiding the generation of solid waste, which is conducive to resource integration and utilization, and more environmentally friendly.

[0082] Secondly, the rotating gear 68 controls the hose 69 to realize movement and discharge, which can maximize the control of the acid liquid contact area, realize instantaneous uniform dispersion, shorten the mixing time of sulfuric acid and phosphoric acid, and disperse the heat source through the design of the fan-shaped injection trajectory, which can alleviate the problem of local high temperature.

[0083] Second embodiment:

[0084] Please refer to Figures 2 to 5 , Figure 8 and Figure 12 , which also includes a material distribution mechanism 8.

[0085] The bottom end of the middle shaft 75 is connected with a second ratchet wheel 710, the outer wall of the second ratchet wheel 710 is sleeved with a second ratchet sleeve 711, and the bottom of the second ratchet sleeve 711 is fixedly provided with a first pulley 712.

[0086] The material distribution mechanism 8 includes a second pulley 81 rotatably installed on the upper surface of the first top cover 3, the outer walls of the first pulley 712 and the second pulley 81 are sleeved with a second belt 82, the shaft center of the first pulley 712 is connected with a stirring rod 83 inside the extraction tank 1 through a key groove, the shaft center of the second pulley 81 is connected with a rotating rod 84 on one side of the stirring rod 83 through a key groove, the outer wall of the rotating rod 84 is fixedly provided with a material distribution disc 85, the side wall of the material distribution disc 85 is fixedly provided with a discharging frame 86, and the side wall of the mixing tank 5 is fixedly provided with a liquid outlet pipe 66.

[0087] The outer walls of the stirring rod 83 and the rotating rod 84 are rotatably connected with the first top cover 3, and the liquid outlet pipe 66 penetrates the inside of the extraction tank 1 and extends to the upper surface of the material distribution disc 85.

[0088] Please refer to Figure 4 andFigure 5 : In the working process of the first embodiment, when the central shaft 75 rotates clockwise, the first ratchet wheel 77 drives the first ratchet gear cover 78 to rotate, while the second ratchet wheel 710 rotates clockwise but does not drive the second ratchet gear cover 711 to rotate. Therefore, in the working process of the first embodiment, the second ratchet gear cover 711 and the first pulley 712 are both stopped working;

[0089] Conversely, if the central shaft 75 rotates counterclockwise, the first ratchet wheel 77 does not drive the first ratchet gear cover 78 to rotate, while the second ratchet wheel 710 rotates counterclockwise to drive the second ratchet gear cover 711 to drive the first pulley 712 to rotate. In this way, the working of the mixing mechanism 6 can be automatically stopped.

[0090] When the first pulley 712 rotates, it drives the second belt 82 to rotate the second pulley 81. The rotation of the first pulley 712 and the second pulley 81 can control the rotation of the stirring rod 83 and the rotating rod 84.

[0091] Please refer to Figure 4 and Figure 3 : The stirring rod 83 can rotate in the extraction tank 1. Through the rotation of the stirring rod 83, the transformed slag and the mixed solution of sulfuric acid and phosphoric acid in the extraction tank 1 can be fully stirred and leached to extract lithium.

[0092] Please refer to Figure 12 : During the rotation of the rotating rod 84, the distribution disc 85 and the discharge frame 86 rotate synchronously. At this time, the mixed solution of sulfuric acid and phosphoric acid in the mixing tank 5 is guided into the distribution disc 85 through the liquid outlet pipe 66 and is uniformly distributed in the discharge frame 86 and mixed with the transformed slag in the extraction tank 1.

[0093] This embodiment:

[0094] The mixed acid of sulfuric acid and phosphoric acid covers the surface of the slag in a dispersed state, and even penetrates into the pores inside the slag particles. This can maximize the contact area between the acid and the lithium-containing material, and avoid the residual of unreacted slag nucleus due to insufficient local acid amount;

[0095] The dispersed contact can reduce the liquid film resistance of the acid solution on the surface of the slag layer, and at the same time can promote the generated lithium elements to quickly separate from the slag body and enter the liquid phase, significantly shorten the lithium leaching reaction time, and improve the lithium recovery rate in the effective time;

[0096] At the same time, the pH value can be stably controlled. The pH value of the mixed solution of sulfuric acid and phosphoric acid needs to be stably controlled in a specific range. The dispersion and distribution can avoid the instantaneous pH value drop caused by the local concentration of the mixed acid, prevent the excessive dissolution of amphoteric metals such as aluminum and iron in the strong acid environment, and at the same time maintain the stability of the overall system pH.

[0097] Third embodiment:

[0098] Please refer to Figure 3And Figure 12 The "L" type sampling pipe 10 is installed inside the extraction tank 1 and below the liquid outlet pipe 66, the bottom end of the rotating rod 84 is fixedly provided with a rotating paddle 87, the top side wall of the extraction tank 1 is provided with a feeding pipe 11, and the bottom end of the extraction tank 1 is provided with a discharging pipe 12.

[0099] Please refer to Figure 3 And Figure 12 : Because the sampling pipe 10 is arranged at the bottom of the rotating paddle 87, in the working process of the second embodiment, the rotating rod 84 drives the rotating paddle 87 to rotate on the sampling pipe 10 during rotation, and the rotating paddle 87 can process the surface scum when rotating on the liquid surface.

[0100] This embodiment:

[0101] During the stirring leaching process, the rotating paddle 87 breaks the scum by mechanical shearing force, so that the liquid in the scum is reflowed to the leaching liquid body, and the solid impurities are settled after the scum is broken. Finally, only pure liquid phase leaching liquid is collected during sampling, so that the composition of the sample is completely consistent with the liquid phase composition of the whole leaching liquid in the tank. After the rotating paddle 87 removes the scum, the liquid surface restores to a single-phase liquid state, and the sampling pipe 10 can directly contact the pure liquid phase. Whether it is volume measurement or mass measurement, it can accurately match the preset sampling amount, and eliminate the deviation from the measurement link.

[0102] Fourth embodiment:

[0103] Please refer to Figures 13 to 15 The method for extracting lithium from overhauled slag based on solid waste resource, comprising the following steps:

[0104] S1: pretreatment;

[0105] The overhauled slag is crushed to 100-200 mesh by a jaw crusher, and uniform carbon slag powder is obtained by screening;

[0106] Primary roasting: oxygen or inert gas is introduced into the tube furnace, and the temperature is raised to 500-800℃ at 8-12℃ / min, and the material after roasting is light gray, and the fluorine and lithium are basically not lost, which promotes the removal of carbon, and the cyanide decomposition rate is >99.8%;

[0107] Secondary roasting: the roasted slag is mixed with calcium hydroxide and calcium sulfate at a mass ratio of 15:2:1, and is roasted at 400-900℃ in a muffle furnace for 0.5-2h to form soluble lithium salt and CaF2;

[0108] S2: acid leaching to extract lithium;

[0109] The transition slag is mixed with 60-98 wt% sulfuric acid and 30-50 wt% phosphoric acid, and after stirring and leaching at 75-90 DEG C for 2 hours, filtration is performed for detection. This step needs to be performed in the extraction tank 1 during the acid leaching of lithium, and the leaching solution has a lithium leaching rate of 95% or more. The acid leaching residue (CaF2 content > 90%, fluorine dissolution rate < 5%).

[0110] S3: lithium precipitation refining;

[0111] The leaching solution is adjusted to pH 12 by adding a CaO suspension, Al and Fe impurities are removed by filtration, 1-1.5 times the stoichiometric amount of trisodium phosphate is added, and the mixture is reacted at 60-80 DEG C for 1 hour. After aging, the mixture is washed with hot water at 90 DEG C for 3 times, and then dried to obtain battery-grade lithium phosphate.

[0112] S4: aluminum fluoride preparation;

[0113] After the acid leaching residue is cleaned with 0.3-0.8 mol / L hydrochloric acid, it is mixed with Al2O3 at an Al / F molar ratio of 1:3, and then placed in a muffle furnace for smelting at 600-900 DEG C for 1 hour to obtain aluminum fluoride.

[0114] The existing lithium extraction technology has obvious defects:

[0115] 1. Incomplete removal of cyanide: the decomposition rate is less than 90% at 600 DEG C in conventional pyrolysis, and residual cyanide contaminates the product;

[0116] 2. Low lithium recovery rate: direct acid leaching leads to a large amount of fluorine dissolution (>20%), forming HF to corrode the equipment, and the lithium leaching rate is less than 80%;

[0117] 3. Fluorine resources are not utilized: the acid leaching residue contains more than 40% fluorine, but the existing technology does not achieve directional conversion.

[0118] The present embodiment:

[0119] The two-stage roasting synergistic effect is adopted: the first-stage oxygen roasting destroys cyanide and promotes the removal of carbon, the second-stage calcium roasting converts lithium into CaLi2(SO4)2 and fluorine into CaF2, the phosphoric acid fluorine control mechanism: the phosphate radical and the dissolved Al 3+ generate an AlPO4 film to wrap calcium fluoride particles, inhibit fluorine dissolution, and the gradient lithium precipitation technology avoids the entrainment of impurities in the lithium phosphate precipitation.

[0120] Please refer to Figures 1 to 12 The working principle of the lithium extraction device and method based on solid waste resource utilization provided by the present application is as follows:

[0121] Step S1, preparation of sulfuric acid and phosphoric acid mixed acid;

[0122] The starting motor 72 controls the driving gear 73 to engage the transmission driven gear 74 to rotate, first the central shaft 75 rotates clockwise, and the first ratchet wheel 77 rotates clockwise under the synchronous control of the first ratchet wheel 77, and the first ratchet wheel 77 rotates clockwise to engage the first ratchet sleeve 78 to drive the driving pulley 79 to rotate clockwise synchronously, and the driving pulley 79 rotates clockwise to drive the first belt 62 to control the driven pulley 61 to rotate, and when the driven pulley 61 rotates, the rotating ring 64 and the mixing rod 63 can rotate clockwise in the mixing tank 5;

[0123] The sulfuric acid and phosphoric acid delivery devices are respectively externally mounted on the two hoses 69 to deliver sulfuric acid and phosphoric acid into the mixing tank 5 through the two hoses 69, and when the rotating ring 64 rotates, the arc-shaped rack 65 rotates to control the rotating gear 68 to control the movement of the hose 69 to inject sulfuric acid and phosphoric acid into the mixing tank 5;

[0124] Step S2, acid leaching lithium;

[0125] The user can externally mount a valve on the liquid outlet pipe 66, and rotate the valve to make the liquid outlet pipe 66 inject the mixed acid in the mixing tank 5 onto the distribution disc 85, and the user controls the central shaft 75 to rotate counterclockwise, so that the first ratchet wheel 77 does not control the first ratchet sleeve 78 to rotate, and the second ratchet wheel 710 rotates counterclockwise to control the first belt wheel 712 to rotate, and the first belt wheel 712 rotates to drive the second belt 82 to control the second belt wheel 81 to rotate, and the first belt wheel 712 and the second belt wheel 81 rotate to control the stirring rod 83 and the rotating rod 84 to rotate, and the starting temperature raising seat 2 raises the temperature of the extraction tank 1 during the leaching process, and the feed pipe 11 is used for discharging the transformed slag, and the discharge pipe 12 is used for discharging the leaching liquid.

[0126] The above description is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation made under the concept of the present application, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.

Claims

1. A lithium extraction device based on overhaul slag from solid waste resource utilization, characterized in that, Includes extraction tank, heating base, side frame, mixing tank, drive mechanism and mixing mechanism; The extraction tank is installed through the inner wall of the heating base, the side frame is fixed to the side wall of the extraction tank, and the mixing tank is installed through the inside of the side frame. The extraction tank is sealed with a first top cover, and a mounting bracket is fixedly mounted on the top of the first top cover. The driving mechanism includes a support base, a motor, and a drive gear. The support base is fixed on the upper surface of the first top cover and located inside the mounting bracket. The motor is mounted on the upper surface of the support base. The drive gear is keyway connected to the output shaft of the motor. A driven gear is meshed with one side of the drive gear. A central shaft is keyway connected to the shaft of the driven gear. A limiting plate is fixedly mounted on the top of the mounting bracket. A first ratchet is keyway connected to the top of the central shaft. A first ratchet sleeve is meshed with the outer wall of the first ratchet. A drive pulley is fixedly mounted at the bottom of the first ratchet sleeve. The mixing tank is sealed with a second top cover. The mixing mechanism includes a driven pulley and a first belt. The driven pulley is rotatably connected to the top of the second top cover. The first belt is sleeved on the outer wall of the drive pulley and the driven pulley. A mixing rod and a rotating ring are connected by a keyway at the axis of the driven pulley and inside the mixing tank. Three arc-shaped racks are fixed on the outer wall of the rotating ring. Two mounting plates are fixed on the inner wall of the mixing tank. A rotating gear is installed above each of the two mounting plates. A hose is installed on the top of each of the two rotating gears.

2. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 1, characterized in that, The first ratchet shaft is rotatably connected to the limiting plate, and the drive pulley is rotatably connected to the mounting bracket.

3. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 1, characterized in that, The first ratchet sleeve and the drive pulley have a hollow design at their shaft center and do not contact the central shaft, which passes through the shaft center of the drive pulley and the first ratchet sleeve.

4. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 1, characterized in that, The three arc-shaped racks are equidistantly distributed in a ring about the center of the rotating ring, and the arc-shaped racks and the rotating gear mesh with each other.

5. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 1, characterized in that, A sleeve is installed inside the mounting plate, and a "T"-shaped positioning rod is rotatably installed inside the sleeve. A torsion spring is sleeved on the outer wall of the positioning rod and inside the sleeve. The axis of the rotating gear is connected to the axis of the positioning rod via a keyway.

6. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 1, characterized in that, It also includes a material distribution mechanism; The bottom keyway of the central shaft is connected to a second ratchet, the outer wall of the second ratchet is fitted with a second ratchet sleeve, and the bottom of the second ratchet sleeve is fixed with a first pulley. The material distribution mechanism includes a second pulley rotatably mounted on the upper surface of the first top cover. A second belt is sleeved on the outer wall of the first pulley and the second pulley. A stirring rod is connected to the axis of the first pulley and the inside of the extraction tank via a keyway. A rotating rod is connected to the axis of the second pulley and the side of the stirring rod via a keyway. A material distribution plate is fixed on the outer wall of the rotating rod. A discharge frame is fixed on the side wall of the material distribution plate. A liquid outlet pipe is fixed on the side wall of the mixing tank.

7. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 6, characterized in that, The outer walls of the stirring rod and the rotating rod are rotatably connected to the first top cover, and the liquid outlet pipe passes through the inside of the extraction tank and extends to the upper surface of the distribution plate.

8. The lithium extraction device based on solid waste resource utilization from overhaul slag according to claim 6, characterized in that, An "L"-shaped sampling tube is installed inside the extraction tank and below the outlet pipe. A rotating blade is fixed at the bottom end of the rotating rod. A feed pipe is installed on the upper side wall of the extraction tank, and an outlet pipe is installed at the bottom end of the extraction tank.

9. A method for lithium extraction from overhaul slag based on solid waste resource utilization, characterized in that, The lithium extraction method based on overhaul slag from solid waste resource utilization includes the lithium extraction device based on overhaul slag from solid waste resource utilization as described in any one of claims 1-8, and includes the following steps: S1: Preprocessing; The overhaul slag is crushed to 100-200 mesh using a jaw crusher and then screened to obtain uniform carbon slag powder. Primary roasting: Oxygen or inert gas is introduced into a tube furnace, and the temperature is raised to 500-800℃ at a rate of 8-12℃ / min and held for 1.5-3 hours. The roasted material is light gray, with minimal loss of fluorine and lithium, promoting carbon removal, and a cyanide decomposition rate of >99.8%. Secondary roasting: The roasting residue is mixed with calcium hydroxide and calcium sulfate in a mass ratio of 15:2:1 and roasted in a muffle furnace at 400-900℃ for 0.5-2 hours to form soluble lithium salt and CaF2; S2: Lithium extraction by acid leaching; The transformation residue is leached with a mixture of 60-98wt% sulfuric acid and 30-50wt% phosphoric acid at 75-90℃ for 2 hours, followed by filtration and testing. This step needs to be carried out in the extraction tank during acid leaching for lithium extraction. S3: Lithium immersion refining; The pH of the leachate was adjusted to 12 by adding CaO suspension, and Al and Fe impurities were removed by filtration. 1-1.5 times the stoichiometric ratio of trisodium phosphate was added, and the mixture was reacted at 60-80℃ for 1 hour. After aging, it was washed three times with hot water at 90℃ and dried to obtain battery-grade lithium phosphate. S4: Preparation of aluminum fluoride; After the acid leaching residue is cleaned with 0.3-0.8 mol / L hydrochloric acid, it is mixed with Al2O3 at an Al / F molar ratio of 1:3 and then smelted in a muffle furnace at 600-900℃ for 1 hour to obtain aluminum fluoride.

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