A method for recycling lithium from lithium feldspar filter residue
By performing steps such as drying, grinding, multi-stage washing, ion exchange, concentration, and lithium carbonate precipitation on spodumene filter residue, the problem of high lithium residue in spodumene filter residue is solved, realizing efficient resource utilization and recycling of lithium and reducing environmental pressure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-21
- Publication Date
- 2026-04-14
AI Technical Summary
Existing technologies for extracting lithium from spodumene filter residue suffer from problems such as high lithium residue, severe equipment corrosion, high concentration of impurity ions, and low added value, failing to effectively realize the resource utilization of lithium.
Battery-grade lithium carbonate is obtained by drying and grinding the spodumene filter residue, followed by multi-stage water washing for lithium extraction, ion exchange and elution, concentration and lithium carbonate precipitation, and finally purification and drying.
This has enabled efficient recycling and utilization of lithium resources, reduced waste emissions, improved lithium recycling rates, reduced environmental pressure, and resolved the supply and demand imbalance of lithium resources.
Smart Images
Figure CN121344382B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of metal recycling technology, and in particular to a method for resource-based lithium extraction from spodumene filter residue. Background Technology
[0002] Lithium metal in spodumene has the advantage of being recyclable. During the lithium extraction process, industrial lithium extraction methods generate a large amount of plate and frame filter residue in the impurity removal stage. Due to the pores of the filter cloth and the precipitation of some impurities, fine lithium salt particles in the lithium-containing solution may be trapped or dissolved lithium may be adsorbed, resulting in a large amount of lithium residue.
[0003] For lithium extraction from plate and frame filter residue, existing technologies mainly focus on acid leaching. This method requires a large amount of strong acid, causes severe equipment corrosion, and results in high concentrations of impurity ions in the leachate, leading to high subsequent purification costs. Most processes only achieve lithium recovery and are not directly linked to the preparation of high-value products, resulting in low added value.
[0004] Therefore, it is necessary to provide a method for resource-based lithium extraction from spodumene filter residue to solve the above-mentioned technical problems. Summary of the Invention
[0005] This invention provides a method for resource-based lithium extraction from spodumene filter residue, which solves the problem in related technologies that requires further research on how to effectively improve the recovery rate of metal resources in plate and frame filter residue.
[0006] To solve the above-mentioned technical problems, the present invention provides a method for resource-based lithium extraction from spodumene filter residue, comprising the following steps:
[0007] Step S100, filter residue pretreatment, the spodumene impurity removal plate and frame filter residue is dried and ground;
[0008] Step S200: Multi-stage water washing for lithium extraction. The ground plate and frame filter residue is washed with water once, twice and three times in sequence, and the three washing solutions are combined as lithium-containing leachate.
[0009] Step S300, Ion exchange and elution: The combined lithium-containing leachate is passed through an ion exchange resin column for ion exchange treatment and elution treatment, and the eluent is collected.
[0010] Step S400: Eluent concentration. The eluent is heated and evaporated on an electric furnace to concentrate it, resulting in a high-concentration lithium solution.
[0011] Step S500, crude lithium carbonate precipitation: a high-concentration lithium solution and a sodium carbonate solution are reacted to generate lithium carbonate precipitate. After the reaction is completed, the solution is filtered while hot to obtain lithium precipitation mother liquor and crude lithium carbonate.
[0012] Step S600: Purification and drying. Wash the crude lithium carbonate with deionized water, and then place the washed precipitate in a forced-air drying oven to obtain battery-grade lithium carbonate.
[0013] Preferably, during the drying process in step S100, the spodumene impurity removal plate and frame filter residue is taken, placed in a forced-air drying oven, and dried at 80-100℃ for 6-12 hours.
[0014] Preferably, in step S100, the dried plate and frame filter residue is ground in a ball mill for 5-6 minutes.
[0015] Preferably, in step S200, during the first water washing: the ground plate and frame filter residue is mixed with deionized water at a solid-liquid ratio of 1:5-1:6, and stirred at 260 rpm for 5-10 minutes at room temperature to ensure uniform dispersion of the system. Then, sodium hexametaphosphate dispersant is added at a mass fraction of 1%-2% of the plate and frame filter residue, and stirring is continued for 50 minutes to form a homogeneous slurry. After the reaction is completed, vacuum filtration is used to separate the solid and liquid, resulting in a first washing liquid and a first washing residue.
[0016] Preferably, in step S200, during the second water washing: the first washing residue is treated according to the above solid-liquid ratio, dispersant dosage and stirring parameters, the stirring time is shortened to 40 min, and after vacuum filtration, solid and liquid are separated to obtain the second washing liquid and the second washing residue.
[0017] Preferably, in step S300, during the three water washings: the second washing residue is treated under the same conditions, the stirring time is shortened to 30 minutes, and after vacuum filtration, solid-liquid separation is performed to obtain the third washing liquid and the third washing residue. The first, second, and third washing liquids are collected respectively, and the three washing liquids are combined as lithium-containing leachate.
[0018] Preferably, in step S300, during the ion exchange treatment, the flow rate is controlled at 1-2 BV / h, and lithium ions are adsorbed at room temperature; during the elution treatment, after the resin is saturated, 0.5-1.0 mol / L dilute hydrochloric acid is used as the eluent, and elution is carried out at a flow rate of 0.5-1 BV / h, and the eluent is collected.
[0019] Preferably, during the evaporation and concentration in step S400, the lithium content is controlled at 30-35 g / L.
[0020] Preferably, in step S500, during the reaction process, a sodium carbonate solution is first prepared. The high-concentration lithium solution and the sodium carbonate solution are heated to 90-100°C, and stirring is started at a frequency of 100-200 Hz. Then, a peristaltic pump is used to slowly add the high-concentration lithium solution dropwise to the sodium carbonate solution at a certain flow rate, controlling the reaction between Na₂CO₃ and Li. + The molar ratio is 1.1-1.2. After the addition is complete, continue stirring for 30-60 minutes to allow Li to fully mature. + With CO32- The reaction proceeds to produce lithium carbonate precipitate. After the reaction is complete, the mixture is filtered while hot to obtain lithium precipitate mother liquor and crude lithium carbonate.
[0021] Preferably, in step S600, when washing the crude lithium carbonate, the crude lithium carbonate is washed 2-3 times with deionized water, with a solid-liquid ratio of 1:5 each time. The mixture is heated to 95-100℃, stirred for 15-20 minutes, and then filtered while hot.
[0022] Compared with related technologies, the method for resource-based lithium extraction from spodumene filter residue provided by the present invention has the following beneficial effects:
[0023] The use of spodumene-based impurity removal plate and frame filter residue to recover lithium resources enables the recycling of metal materials from solid waste, meeting the needs of comprehensive metal resource recycling, realizing the resource-based circular utilization of metal materials, reducing waste emissions, and improving the recycling rate of metal resources. Attached Figure Description
[0024] 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.
[0025] Figure 1 This is a flowchart of the first embodiment of the method for resource-based lithium extraction from spodumene filter residue provided by the present invention;
[0026] Figure 2 A flowchart of a method for resource-based lithium extraction from spodumene filter residue provided by the present invention;
[0027] Figure 3 A three-dimensional view of a first embodiment of the ion exchange resin column provided by the present invention;
[0028] Figure 4 for Figure 3 The diagram shows the structure of the AA cross section;
[0029] Figure 5 for Figure 4 Top view of the switch cover section shown;
[0030] Figure 6 for Figure 3 The diagram shows a structural schematic of the BB cross-section.
[0031] Figure 7 for Figure 4 A top view of the cross-sectional structure of the connecting shaft shown;
[0032] Figure 8 for Figure 4 The diagram shown illustrates the structure of the switch cover rotating to the eluent filling position.
[0033] Figure 9 A three-dimensional view of a second embodiment of the ion exchange resin column provided by the present invention;
[0034] Figure 10 for Figure 9 The right view of the entire structure shown;
[0035] Figure 11 for Figure 10 The top view of the two second filling pipes shown is a sectional view. Figure 11 (a) is Figure 10 The top view of the connecting structure of the second filling pipe on the left is shown. Figure 11 (b) is Figure 10 The top view of the second filling pipe connection structure shown on the right.
[0036] Explanation of icon numbers:
[0037] 1. Exchange fittings; 11. Outer pipe; 12. Switch cover; 13. Connecting shaft; 14. Filter plate; 121. Connecting hole; 131. Slide groove;
[0038] 2. First filling pipe;
[0039] 3. First discharge pipe;
[0040] 4. Second filling pipe;
[0041] 5. Second discharge pipe;
[0042] 6. Third filling pipe;
[0043] 7. Third discharge pipe;
[0044] 8. Telescopic components;
[0045] 9. Driving components; 91. Synchronizing rod; 92. Transmission components;
[0046] 10. Install the bracket.
[0047] 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
[0048] 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.
[0049] This invention provides a method for resource-based lithium extraction from spodumene filter residue. Please refer to [link to relevant documentation]. Figure 1 The method for resource-based lithium extraction from spodumene filter residue in this invention includes the following steps:
[0050] Step S100, filter residue pretreatment, the spodumene impurity removal plate and frame filter residue is dried and ground;
[0051] Step S200: Multi-stage water washing for lithium extraction. The ground plate and frame filter residue is washed with water once, twice and three times in sequence, and the three washing solutions are combined as lithium-containing leachate.
[0052] Step S300, Ion exchange and elution: The combined lithium-containing leachate is passed through an ion exchange resin column for ion exchange treatment and elution treatment, and the eluent is collected.
[0053] Step S400: Eluent concentration. The eluent is heated and evaporated on an electric furnace to concentrate it, resulting in a high-concentration lithium solution.
[0054] Step S500, crude lithium carbonate precipitation: a high-concentration lithium solution and a sodium carbonate solution are reacted to generate lithium carbonate precipitate. After the reaction is completed, the solution is filtered while hot to obtain lithium precipitation mother liquor and crude lithium carbonate.
[0055] Step S600: Purification and drying. The crude lithium carbonate is washed with deionized water, and then the washed precipitate is placed in a forced-air drying oven for air drying to obtain battery-grade lithium carbonate.
[0056] The use of spodumene-based impurity removal plate and frame filter residue to recover lithium resources enables the recycling of metal materials from solid waste, meeting the needs of comprehensive metal resource recycling, realizing the resource-based circular utilization of metal materials, reducing waste emissions, and improving the recycling rate of metal resources.
[0057] Specifically, during the drying process in step S100, the spodumene impurity removal plate and frame filter residue is taken, placed in a forced-air drying oven, and dried at 80-100℃ for 6-12 hours.
[0058] Effectively prevents particle agglomeration during the grinding process.
[0059] Specifically, in step S100, the dried plate and frame filter residue is ground in a ball mill for 5-6 minutes.
[0060] By refining the particles to increase their specific surface area, the solid-liquid contact area is increased, significantly optimizing the subsequent leaching mass transfer efficiency.
[0061] Specifically, in step S200, during the first water washing: the ground plate and frame filter residue is mixed with deionized water at a solid-liquid ratio of 1:5-1:6, and stirred at 260 rpm for 5-10 minutes at room temperature to ensure uniform dispersion of the system. Then, sodium hexametaphosphate dispersant is added at a mass fraction of 1%-2% of the plate and frame filter residue, and stirring is continued for 50 minutes to form a homogeneous slurry. After the reaction is completed, vacuum filtration is used to separate the solid and liquid, resulting in a first washing liquid and a first washing residue.
[0062] Sodium hexametaphosphate can enhance the negative charge on the mineral surface, reduce particle aggregation, and promote the dissolution of soluble lithium salts.
[0063] Specifically, in step S200, during the second water washing: the first washing residue is processed according to the above solid-liquid ratio, dispersant dosage and stirring parameters, the stirring time is shortened to 40 min, and after vacuum filtration, solid and liquid are separated to obtain the second washing liquid and the second washing residue.
[0064] Specifically, in step S300, during the three water washings: the second washing residue is treated under the same conditions, the stirring time is shortened to 30 minutes, and after vacuum filtration, solid-liquid separation is performed to obtain the third washing liquid and the third washing residue. The first, second, and third washing liquids are collected respectively, and the three washing liquids are combined as lithium-containing leaching solution.
[0065] Specifically, in step S300, during the ion exchange treatment, the flow rate is controlled at 1-2 BV / h, and lithium ions are adsorbed at room temperature; during the elution treatment, after the resin is saturated, 0.5-1.0 mol / L dilute hydrochloric acid is used as the eluent, and elution is carried out at a flow rate of 0.5-1 BV / h, and the eluent is collected.
[0066] Specifically, during the evaporation and concentration in step S400, the lithium content is controlled at 30-35 g / L.
[0067] Specifically, in step S500, during the reaction process, a sodium carbonate solution is first prepared. The high-concentration lithium solution and the sodium carbonate solution are heated to 90-100°C, and stirring is started at a frequency of 100-200 Hz. Then, a peristaltic pump is used to slowly add the high-concentration lithium solution dropwise to the sodium carbonate solution at a certain flow rate, controlling the reaction between Na₂CO₃ and Li. + The molar ratio is 1.1-1.2. After the addition is complete, continue stirring for 30-60 minutes to allow Li to fully mature. + With CO3 2-The reaction proceeds to produce lithium carbonate precipitate. After the reaction is complete, the mixture is filtered while hot to obtain lithium precipitate mother liquor and crude lithium carbonate.
[0068] Specifically, in step S600, when washing the crude lithium carbonate, the crude lithium carbonate is washed 2-3 times with deionized water, with a solid-liquid ratio of 1:5 each time. The mixture is heated to 95-100℃, stirred for 15-20 minutes, and then filtered while hot.
[0069] Specifically, in step S600, during the air-drying process, the washed precipitate is placed in a forced-air drying oven and dried at 80-100℃ for 4-6 hours to obtain battery-grade lithium carbonate.
[0070] Furthermore, the method for resource-based lithium extraction from spodumene filter residue further includes step S700, preparing sodium chloride crystals by slowly adding concentrated hydrochloric acid dropwise to the lithium precipitation mother liquor for decarbonization treatment to remove the remaining carbonate ions and obtain sodium chloride crystals.
[0071] Specifically, during the decarbonization process in step S700, the addition of sodium chloride was stopped when the pH dropped to 2.0-3.0, and stirring was continued for 10-20 minutes. After the reaction was completed, the sodium chloride solution was placed in a freezer at -5-0°C for 3-6 hours to obtain crude sodium chloride crystals. The obtained crude sodium chloride crystals were then washed and filtered 2-3 times with a small amount of -5-0°C ice water, and finally placed in a forced-air drying oven at 80-100°C for 4-6 hours to obtain sodium chloride crystals.
[0072] The beneficial effects of the method for resource-based lithium extraction from spodumene filter residue provided by this invention are as follows:
[0073] The process is green and environmentally friendly: In the lithium recycling process of this invention, impurity ions are removed by precipitation, making the recycling process environmentally friendly. Moreover, it solves some environmental problems such as soil pollution caused by filter residue storage, effectively reducing environmental pressure.
[0074] High-efficiency lithium resource recovery: It achieves selective enrichment and efficient recovery of lithium, which is far higher than the resource utilization rate of traditional stockpiling or landfill treatment. This not only transforms industrial solid waste into usable lithium resources, but also reduces dependence on primary spodumene mines and alleviates the contradiction between lithium resource supply and demand.
[0075] The present invention also provides an ion exchange resin column for ion exchange and elution in the method for resource-based lithium extraction from spodumene filter residue.
[0076] First embodiment:
[0077] Please refer to the following: Figures 3 to 6 In this invention, the ion exchange resin column comprises:
[0078] The exchange fitting 1 includes an outer pipe 11, two switch covers 12, and a connecting shaft 13. The switch covers 12 are movably installed inside the outer pipe 11. The connecting shaft 13 is fixedly connected to the two switch covers 12. The two switch covers 12 are symmetrically arranged vertically. The switch covers 12 have mating holes 121. A filter plate 14 is embedded in the switch covers 12. The bottom of the connecting shaft 13 has a sliding groove 131. The two switch covers 12 and the connecting shaft 13 form an "I-shaped filter valve".
[0079] The outer tube 11 is equipped with a first filling pipe 2, a first discharge pipe 3, a second filling pipe 4, a second discharge pipe 5, a third filling pipe 6, and a third discharge pipe 7.
[0080] Telescopic component 8, which is fixed to the top of the outer tube 11, and whose telescopic part passes through the outer tube 11 and is rotatably connected to the switch cover 12;
[0081] The driving component 9 has a rotating part fixedly provided with a synchronizing rod 91. The top of the synchronizing rod 91 passes through the bottom of the outer tube 11 and is inserted into the sliding groove 131. The synchronizing rod 91 is key-connected to the connecting shaft 13.
[0082] The first filling pipe 2, the second filling pipe 4, and the third filling pipe 6 are all located within the rotation range of the top switch cover 12; the first discharge pipe 3, the second discharge pipe 5, and the third discharge pipe 7 are all located within the rotation range of the bottom switch cover 12.
[0083] The sliding key connection means that while the synchronizing rod 91 can drive the connecting shaft 13 to rotate synchronously, the connecting shaft 13 can also slide up and down relative to the synchronizing rod 91. This ensures that the rotational and sliding adjustments of the connecting shaft 13 do not interfere with each other.
[0084] In this embodiment, the telescopic member 8 can be any one of an electric telescopic rod, a hydraulic telescopic rod, or a telescopic cylinder, used to drive the lifting and lowering adjustment of the switch cover 12.
[0085] Specifically, the second filling tube 4 and the third filling tube 6 are at the same horizontal level;
[0086] The second discharge pipe 5 and the third discharge pipe 7 are at the same horizontal level;
[0087] The first filling tube 2 is located below the horizontal range of the second filling tube 4;
[0088] The first discharge pipe 3 is located above the horizontal range of the second discharge pipe 5.
[0089] In this embodiment, as Figure 4 As shown, an I-shaped filter valve and the outer tube 11 surround to form a storage chamber, the scope of which is used to store the resin to be installed and used.
[0090] I-shaped filter valves include three operating modes:
[0091] In the resin filling mode, the telescopic component 8 controls the I-shaped filter valve to move upward relative to the outer tube 11, so that the first filling tube 2 opens and connects to the storage chamber, so that the resin can be injected into the storage chamber through the first filling tube 2, which facilitates the filling of resin.
[0092] Resin usage patterns, such as Figure 4 , Figure 6 and Figure 8 As shown, the first filling tube 2 and the first discharge tube 3 are blocked and closed by the upper and lower switch covers 12. The second filling tube 4 and the third filling tube 6 are located within the rotation range of the top switch cover 12, and the second discharge tube 5 and the third discharge tube 7 are located within the rotation range of the bottom switch cover 12. When the two docking holes 121 are connected to the second filling tube 4 and the second discharge tube 5 respectively, it is convenient to perform ion exchange treatment on the raw material solution. When the two docking holes 121 are connected to the third filling tube 6 and the third discharge tube 7 respectively, it is convenient to perform elution treatment on the used resin.
[0093] In the resin discharge mode, the telescopic component 8 controls the I-shaped filter valve to move downward relative to the outer pipe 11, so that the first discharge pipe 3 opens and connects to the storage chamber, which facilitates the discharge of resin after the service cycle, so as to facilitate the discharge and replacement of resin in the outer pipe 11.
[0094] The drive component 9 is a motor structure, which provides a power source for the rotational adjustment of the synchronizing rod 91, so as to facilitate the rotational adjustment of the I-shaped filter valve.
[0095] Mode switching principle:
[0096] Let's define it as follows: In the initial state, the I-shaped filter valve is in resin use mode. When resin is added for the first time, the telescopic component 8 is activated. The telescopic component 8 drives one of the switch covers 12 to move upward. One of the switch covers 12 drives the other switch cover 12 to move upward as a whole through the connecting shaft 13. One switch cover 12 moves upward and moves out of the input range of the first filling pipe 2, so that the first filling pipe 2 is connected to the storage chamber. The I-shaped filter valve switches from resin use mode to resin filling mode, and the required ion exchange resin is added into the storage chamber through the first filling pipe 2.
[0097] After the ion exchange resin is filled, the telescopic component 8 is activated again. The telescopic component 8 drives one of the switch covers 12 to move down. One of the switch covers 12 drives the other switch cover 12 to move down as a whole through the connecting shaft 13. One switch cover 12 moves down and blocks the input range of the first filling tube 2. The I-shaped filter valve switches from the resin filling mode to the resin use mode.
[0098] When the ion exchange resin needs to be discharged, the telescopic component 8 is activated again. The telescopic component 8 drives one of the switch covers 12 to move down. One of the switch covers 12 drives the other switch cover 12 to move down as a whole through the connecting shaft 13. The other switch cover 12 moves down and leaves the output range of the first discharge pipe 3, so that the first discharge pipe 3 is connected to the storage chamber, which facilitates the discharge of resin in the storage chamber and makes it easier to replace the resin after it reaches the end of its service life.
[0099] The working principle of the drive unit 9 in different modes:
[0100] When the I-shaped filter valve is in resin filling mode, during the resin injection into the storage chamber, the drive component 9 is activated. The drive component 9 drives the synchronizing rod 91 to rotate, and the synchronizing rod 91 synchronously drives the I-shaped filter valve to rotate as a whole, so that the injected resin is evenly distributed within the storage chamber, making the resin distribution after injection more compact and increasing the full contact between the resin and the raw materials during use.
[0101] When the I-shaped filter valve is in resin use mode, the drive unit 9 is activated, and the drive unit 9 drives the synchronous rod 91 to rotate. The synchronous rod 91 synchronously drives the I-shaped filter valve to rotate as a whole, so that the docking hole 121 rotates synchronously with the switch cover 12.
[0102] When the top docking hole 121 is connected to the second filling pipe 4, the bottom docking hole 121 is connected to the second discharge pipe 5, which facilitates the injection of raw material solution. When the raw material solution is injected from the second filling pipe 4, it first passes through the range of the filter plate 14 and then enters the range of the storage chamber. After the raw material solution comes into contact with the resin, ion exchange occurs. The solution after ion exchange is discharged from the second discharge pipe 5 to facilitate the ion exchange treatment of the raw material solution.
[0103] When the top docking hole 121 is connected to the third injection pipe 6, the bottom docking hole 121 is connected to the third discharge pipe 7, which facilitates the injection of eluent. When the eluent is injected from the third injection pipe 6, it first passes through the range of the filter plate 14 and then enters the range of the storage chamber. After the eluent comes into contact with the resin, elution occurs. The eluted solution is discharged from the third discharge pipe 7 to facilitate the elution of the resin after ion exchange.
[0104] When the I-shaped filter valve is in resin discharge mode, the drive component 9 is activated, and the drive component 9 drives the synchronizing rod 91 to rotate. The synchronizing rod 91 synchronously drives the I-shaped filter valve to rotate as a whole, so that the resin in the storage chamber is stably discharged from the first discharge pipe 3 under the action of rotational centrifugal force, which facilitates the rapid discharge of resin.
[0105] When the I-shaped filter valve is in resin filling mode, the drive unit 9 can evenly and densely distribute the filled resin within the storage chamber. When the I-shaped filter valve is in resin use mode, the drive unit 9 can quickly switch the solution filling pipeline. When the I-shaped filter valve is in resin discharge mode, the drive unit 9 can quickly rotate and discharge the used resin, improving the efficiency of resin replacement. Thus, the drive unit 9 can play different roles in different use modes to meet the usage requirements of ion exchange resins.
[0106] In this embodiment, the driving component 9 can be fixedly installed at the bottom of the outer tube 11 to provide stable support for the driving component 9 to drive the synchronous rod 91 to rotate relative to the outer tube 11.
[0107] In this embodiment, at least four filter plates 14 are provided on one of the switch covers 12, and the four filter plates 14 are evenly distributed on the switch cover 12.
[0108] Increase the throughput efficiency of the solution and ensure stable delivery and passage of the injected solution.
[0109] In this embodiment, by integrating the filter plate 14 on the switch cover 12, the installed resin can be stored within the storage chamber, forming an isolation and protection for the resin, preventing the resin from clogging the solution output port, and ensuring the stability of the equipment operation.
[0110] Specifically, the slide groove 131 can be a rectangular groove structure, and the top end of the synchronizing rod 91 can be a rectangular rod structure. After the top end of the synchronizing rod 91 is inserted into the slide groove 131, it is slidably connected to the connecting shaft 13; the bottom of the synchronizing rod 91 has a circular structure. This ensures the stability of the synchronizing rod 91 during rotational adjustment on the outer tube 11.
[0111] This allows the connecting shaft 13 to slide and adjust relative to the synchronizing rod 91, while the synchronizing rod 91 can also synchronously drive the connecting shaft 13 to rotate and adjust when it rotates.
[0112] The working principle of the ion exchange resin column provided in this embodiment is as follows:
[0113] Step A1: When adding resin, first activate the telescopic component 8. The telescopic component 8 drives the I-shaped filter valve to switch from the resin use mode to the resin filling mode. The resin is then filled into the storage chamber through the first filling pipe 2, which facilitates the filling of resin before the equipment is used.
[0114] Step A2, during resin operation, first activate the telescopic component 8, which drives the I-shaped filter valve to switch from resin filling mode to resin use mode;
[0115] In resin usage mode, when the two docking holes 121 are respectively connected to the second filling pipe 4 and the second discharge pipe 5, the raw material solution is injected into the interior of the outer pipe 11 from the second filling pipe 4. After passing through the filter plate 14, the raw material solution enters the storage chamber. After the raw material solution comes into full contact with the resin, an ion exchange reaction occurs, realizing the ion exchange treatment of the raw material solution. The treated tail liquid is discharged outward from the second discharge pipe 5.
[0116] When the resin is saturated, the drive unit 9 is activated, which drives the synchronous rod 91 to rotate. The synchronous rod 91 drives the connecting shaft 13 to rotate, and the connecting shaft 13 drives the two switch covers 12 to rotate synchronously, so that the two docking holes 121 rotate and are respectively connected to the third injection pipe 6 and the third discharge pipe 7. The eluent is injected into the interior of the outer pipe 11 through the third injection pipe 6. After passing through the filter plate 14, the eluent enters the storage chamber. After the eluent comes into full contact with the resin, the saturated resin is eluted. The eluent is discharged outward from the third discharge pipe 7 after passing through the filter plate 14 at the bottom.
[0117] Step A3, when discharging resin, first activate the telescopic component 8. The telescopic component 8 drives the I-shaped filter valve to switch from the resin use mode to the resin discharge mode, and discharges the used resin outward through the third discharge pipe 7, which facilitates the discharge of resin after the equipment is used.
[0118] Step A4: After the resin has been completely discharged after use, reset the equipment and repeat step A1.
[0119] Second embodiment:
[0120] Please refer to the following: Figures 9 to 11 Based on the ion exchange resin column provided in the first embodiment of the present invention, the second embodiment of the present invention proposes another ion exchange resin column. 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.
[0121] Specifically, the difference in the ion exchange resin column provided in the second embodiment of the present invention is that two exchange tubes 1 are provided, the two exchange tubes 1 have the same installation structure, and both exchange tubes 1 are installed on the mounting bracket 10.
[0122] Each of the two exchange pipe fittings 1 is provided with a driving component 9, the top of the driving component 9 is fixed on the mounting bracket 10, and the two synchronizing rods 91 are connected by a transmission component 92.
[0123] The driving component 9 drives the two synchronous rods 91 to rotate and adjust simultaneously through the transmission component 92. The two synchronous rods 91 synchronously drive the two I-shaped filter valves to rotate and switch, so that one of the two exchange tubes 1 is in use and the other is on standby, for continuous ion exchange treatment of the raw material solution.
[0124] The transmission component 92 includes two synchronous pulleys and a synchronous belt. The synchronous pulleys are fixed on the synchronous rod 91, and the synchronous belt drives the two synchronous pulleys.
[0125] like Figure 10 As shown, let us define the exchange fitting 1 on the left as resin column a and the exchange fitting 1 on the right as resin column b.
[0126] The I-shaped filter valve has two operating states under resin usage conditions:
[0127] Raw material filling status, such as Figure 11 As shown in (a), the corresponding second injection tube 4 is open and the third injection tube 6 is closed, which facilitates the injection of the raw material solution into the storage chamber, thereby facilitating the ion exchange treatment of the raw material solution;
[0128] Eluent filling status, such as Figure 11 As shown in (b), the corresponding second injection tube 4 is closed and the third injection tube 6 is opened, which facilitates the injection of eluent into the storage chamber, thereby facilitating the elution of saturated resin.
[0129] Continuous processing principle of raw material solution:
[0130] Let's define it as follows: In the initial state, both resin column a and resin column b are in resin use mode and are pre-filled with resin. Resin column a is in the raw material filling state, and resin column b is in the eluent filling state.
[0131] When the equipment is used for the first time, the raw material solution is injected into the inside of resin column a to achieve ion exchange treatment of the raw material solution in resin column a; no eluent is injected into resin column b to support subsequent continuous use.
[0132] When the resin inside resin column a is saturated, the drive unit 9 is activated. The drive unit 9 synchronously drives the two synchronous rods 91 to rotate through the transmission unit 92. The two synchronous rods 91 synchronously drive the two I-shaped filter valves to rotate and adjust, so that the I-shaped filter valves on resin column a switch from the raw material filling state to the eluent filling state. At the same time, the I-shaped filter valves on resin column b switch from the eluent filling state to the raw material filling state, thus realizing the synchronous switching of the working states of resin column a and resin column b.
[0133] A raw material solution is injected into the interior of resin column b to achieve ion exchange treatment of the raw material solution in resin column b. An eluent is injected into resin column a to achieve continuous ion exchange treatment of the raw material solution, while simultaneously eluting the saturated resin in resin column a.
[0134] Similarly, when the resin in resin column b is saturated, the working states of resin column a and resin column b are switched synchronously, so that the equipment is reset to the initial state. The raw material solution is injected into resin column a to continue the ion exchange treatment of the raw material solution; the eluent is injected into resin column b to simultaneously achieve the elution treatment of the saturated resin in resin column b.
[0135] The working principle of the ion exchange resin column provided in this embodiment is as follows:
[0136] Step B1: When using it for the first time, inject the raw material solution into resin column a and perform ion exchange treatment on the raw material solution. Do not inject eluent into resin column b.
[0137] Step B2: After the resin in resin column a is saturated, the working states of resin column a and resin column b are switched synchronously, so that resin column a switches from raw material charging state to eluent charging state, and resin column b switches from eluent charging state to raw material charging state.
[0138] Step B3: Inject the raw material solution into resin column b and continuously perform ion exchange treatment on the raw material solution. At the same time, inject the eluent into resin column a and perform elution treatment on the saturated resin.
[0139] 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 resource-based lithium extraction from spodumene filter residue, characterized in that, Includes the following steps: Step S100, filter residue pretreatment, the spodumene impurity removal plate and frame filter residue is dried and ground; Step S200: Multi-stage water washing for lithium extraction. The ground plate and frame filter residue is washed with water once, twice and three times in sequence, and the three washing solutions are combined as lithium-containing leachate. Step S300, Ion exchange and elution: The combined lithium-containing leachate is passed through an ion exchange resin column for ion exchange treatment and elution treatment, and the eluent is collected. Step S400: Eluent concentration. The eluent is heated and evaporated on an electric furnace to concentrate it, resulting in a high-concentration lithium solution. Step S500, crude lithium carbonate precipitation: a high-concentration lithium solution and a sodium carbonate solution are reacted to generate lithium carbonate precipitate. After the reaction is completed, the solution is filtered while hot to obtain lithium precipitation mother liquor and crude lithium carbonate. Step S600: Purification and drying. Wash the crude lithium carbonate with deionized water, and then place the washed precipitate in a forced-air drying oven to obtain battery-grade lithium carbonate. The ion exchange resin column comprises: The exchange pipe fitting includes an outer pipe, two switch covers, and a connecting shaft. The switch covers are movably installed inside the outer pipe, and the connecting shaft is fixedly connected to the two switch covers. The two switch covers are symmetrically arranged vertically. The switch covers have mating holes and filter plates are embedded in them. The bottom of the connecting shaft has a sliding groove. The two switch covers and the connecting shaft form an "I-shaped filter valve". The outer tube is equipped with a first filling pipe, a first discharge pipe, a second filling pipe, a second discharge pipe, a third filling pipe, and a third discharge pipe. A telescopic component is fixed to the top of the outer tube, and the telescopic part of the telescopic component passes through the outer tube and is rotatably connected to the switch cover. A driving component, wherein a synchronizing rod is fixedly mounted on the rotating part of the driving component, the top of the synchronizing rod penetrates the bottom of the outer tube and is inserted into the sliding groove, and the synchronizing rod is keyed to the connecting shaft; The first filling pipe, the second filling pipe, and the third filling pipe are all located within the rotation range of the top of the switch cover; the first discharge pipe, the second discharge pipe, and the third discharge pipe are all located within the rotation range of the bottom of the switch cover.
2. The method for resource-based lithium extraction from spodumene filter residue according to claim 1, characterized in that, During the drying process in step S100, the spodumene impurity removal plate and frame filter residue is taken and placed in a forced-air drying oven and dried at 80-100℃ for 6-12 hours.
3. The method for resource-based lithium extraction from spodumene filter residue according to claim 2, characterized in that, In step S100, the dried plate and frame filter residue is ground in a ball mill for 5-6 minutes.
4. The method for resource-based lithium extraction from spodumene filter residue according to claim 3, characterized in that, In step S200, during the first water washing: the ground plate and frame filter residue is mixed with deionized water at a solid-liquid ratio of 1:5-1:6, and stirred at 260 rpm for 5-10 minutes at room temperature to ensure uniform dispersion of the system. Then, sodium hexametaphosphate dispersant is added at a mass fraction of 1%-2% of the plate and frame filter residue, and stirring is continued for 50 minutes to form a homogeneous slurry. After the reaction is completed, vacuum filtration is used to separate the solid and liquid, resulting in a first washing liquid and a first washing residue.
5. The method for resource-based lithium extraction from spodumene filter residue according to claim 4, characterized in that, In step S200, during the second water washing: the first washing residue and deionized water are mixed at a solid-liquid ratio of 1:5-1:6, and stirred at 260 rpm for 5-10 minutes at room temperature to ensure uniform dispersion of the system. Then, sodium hexametaphosphate dispersant is added at a mass fraction of 1%-2% of the first washing residue, and stirring is continued for 40 minutes. After vacuum filtration, the solid and liquid are separated to obtain the second washing liquid and the second washing residue.
6. The method for resource-based lithium extraction from spodumene filter residue according to claim 5, characterized in that, In step S200, during the three water washings: the second washing residue is mixed with deionized water at a solid-liquid ratio of 1:5-1:6, and stirred at 260 rpm for 5-10 minutes at room temperature to ensure uniform dispersion of the system. Then, sodium hexametaphosphate dispersant is added at a mass fraction of 1%-2% of the second washing residue, and stirring is continued for 30 minutes. After vacuum filtration, the solid and liquid are separated to obtain the third washing liquid and the third washing residue. The first, second, and third washing liquids are collected separately, and the third washing liquid is combined as a lithium-containing leaching solution.
7. The method for resource-based lithium extraction from spodumene filter residue according to claim 6, characterized in that, In step S300, during the ion exchange treatment, the flow rate is controlled at 1-2 BV / h, and lithium ions are adsorbed at room temperature. During the elution treatment, after the resin is saturated, 0.5-1.0 mol / L dilute hydrochloric acid is used as the eluent, and elution is carried out at a flow rate of 0.5-1 BV / h, and the eluent is collected.
8. The method for resource-based lithium extraction from spodumene filter residue according to claim 7, characterized in that, During the evaporation and concentration in step S400, the lithium content is controlled at 30-35 g / L.
9. The method for resource-based lithium extraction from spodumene filter residue according to claim 8, characterized in that, In step S500, during the reaction process, a sodium carbonate solution is first prepared. The high-concentration lithium solution and the sodium carbonate solution are heated to 90-100°C, and stirring is started at a frequency of 100-200 Hz. Then, a peristaltic pump is used to slowly add the high-concentration lithium solution dropwise to the sodium carbonate solution at a certain flow rate, controlling the reaction between Na₂CO₃ and Li. + The molar ratio is 1.1-1.
2. After the addition is complete, continue stirring for 30-60 minutes to allow Li to fully mature. + With CO3 2- The reaction proceeds to produce lithium carbonate precipitate. After the reaction is complete, the mixture is filtered while hot to obtain lithium precipitate mother liquor and crude lithium carbonate.
10. The method for resource-based lithium extraction from spodumene filter residue according to claim 9, characterized in that, In step S600, when washing the crude lithium carbonate, the crude lithium carbonate is washed 2-3 times with deionized water, with a solid-liquid ratio of 1:5 each time. The mixture is heated to 95-100℃, stirred for 15-20 minutes, and then filtered while hot.
Citation Information
Patent Citations
Equipment and process for extracting lithium from lepidolite frame slag and synthesizing urea gypsum
CN120555742A