Efficient dynamic leaching and purifying system for lepidolite clinker and control method of efficient dynamic leaching and purifying system
By using a dynamic leaching purification system and automated control, the problems of long leaching cycles and low efficiency of lithium mica clinker have been solved, achieving efficient and low-cost lithium recovery and impurity removal, and improving process stability and lithium leaching rate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-17
- Publication Date
- 2026-03-20
AI Technical Summary
Existing leaching processes for lithium mica clinker suffer from problems such as long leaching cycles, low efficiency, high energy consumption, poor raw material adaptability, and rigid processes, resulting in low lithium recovery rates, high impurity purification costs, and difficulty in adapting to changes in the grade and physical properties of different lithium ores.
A dynamic leaching purification system is adopted, which includes sequentially connected soaking tanks, clean water tanks, impurity removal tanks and filter press components. Combined with internal circulation pumps and cross-group liquid transfer, the system uses a PLC central control system to achieve automatic adjustment, integrates defluorination and magnetized sedimentation processes, and optimizes the leaching liquid transfer method to improve leaching efficiency and impurity removal effect.
The leaching cycle was shortened to 4 days, the lithium leaching rate was increased to 85.3%, the residual Li2O in the residue was reduced to 0.188%, the impurity purification cost was reduced by 40%, and the process stability was improved to 95%, achieving efficient and low-cost lithium recovery.
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Figure CN121700166A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of lithium refining technology, and in particular to a highly efficient dynamic leaching purification system for lepidolite clinker and its control method. Background Technology
[0002] Lithium extraction is a core link in the new energy industry chain, and the leaching efficiency of lepidolite clinker directly affects lithium recovery rate and production cost. In traditional processes, spodumene or lepidolite needs to be roasted at high temperatures (such as in a tunnel kiln or rotary kiln) to form porous clinker, which is then extracted through leaching. However, existing technologies generally suffer from the following problems: 1. Long leaching cycle and low efficiency: Traditional leaching processes (such as static soaking) require 5-7 days, resulting in a Li2O residue of 0.3%-0.5% in the leaching residue and a lithium leaching rate of only 70%-80%. For example, a company using a tunnel kiln to roast clinker (Li2O content 1.2%) found that after 4 days of leaching, the Li2O content in the residue was still 0.35%, and the lithium recovery rate was less than 75%.
[0003] 2. Energy consumption and environmental pressure: High-temperature roasting (such as rotary kiln requiring 930℃) and long-term leaching result in high energy consumption (≥60kWh of electricity per ton of clinker), and the accumulation of impurities such as fluorine and iron in the leachate requires multi-stage purification, increasing wastewater treatment costs by more than 30%.
[0004] 3. Poor adaptability to raw materials: Traditional processes lack precise control over the ratio of raw materials and auxiliary materials and the particle size of granulation, resulting in uneven structure of the roasted clinker and poor permeability of the leachate. For example, in one case, due to the excessively large particle size (>15mm), the leachate could not penetrate the interior of the clinker, and the lithium leaching rate plummeted to 65%.
[0005] 4. Rigid processes: Existing technologies mostly rely on fixed parameters (such as a liquid-to-solid ratio of 3:1 and a leaching temperature of room temperature), lacking dynamic adjustment capabilities and making it difficult to adapt to changes in the grade and physical properties of different lithium ores.
[0006] Due to the aforementioned issues, the contradiction between the surge in lithium resource demand and inefficient processes has become prominent; environmental regulations are becoming increasingly stringent, and traditional high-energy-consuming and high-polluting processes are becoming unsustainable; there is an urgent need to achieve the goal of "short cycle and high leaching rate" through raw material optimization and process innovation.
[0007] In existing technologies, lithium leaching for deterioration includes the following three main methods: 1) Tunnel kiln roasting and static leaching method: The tunnel kiln roasting process mainly includes: a roasting temperature of 900-950℃, a granulation particle size of 10-15mm, and a Li2O content of 1.2%-1.3% in the clinker. The static leaching process mainly includes: static soaking for 4-6 days, a liquid-to-solid ratio of 3:1, and leaching at room temperature. The above processes have the following disadvantages: low leaching rate: after 4 days of leaching, the residual Li2O in the slag is only 0.35%-0.45%, and the lithium recovery rate is only 70%-75%; high energy consumption: the energy consumption of tunnel kiln roasting is 1.2 times that of rotary kiln roasting, and the long leaching cycle leads to increased overall costs; and coarse particle size control: the granulation particle size is too large, resulting in low leachate penetration efficiency (after 4 days of leaching, the Li2O content in the slag is 0.42%, the lithium recovery rate is 73%, and subsequent purification costs account for 35% of the total cost).
[0008] 2) Rotary kiln firing + intermittent circulating leaching method: The main process of rotary kiln roasting: the rotary kiln roasting temperature is 930℃, the granulation particle size is 8-12mm, and the clinker Li2O content is 1.25%; the main process of intermittent circulation leaching: intermittent circulation (Q=100m³ / h pump), leaching cycle is 4 days, leaching at room temperature (slag Li2O content is 0.28%, lithium recovery rate is 78%). Disadvantages: (1) Insufficient circulation efficiency: the low pump flow rate leads to poor flow of leaching liquid at the edge of the pool, and slag Li2O residue is 0.25%-0.3%; (2) Serious accumulation of impurities: the fluoride ion concentration in the circulating liquid reaches 500mg / L, and additional defluorinating agent needs to be added (cost increases by 20%); (3) High dependence on manual labor: liquid level and pH adjustment depend on manual labor, and the process stability is only 80%.
[0009] 3) High-temperature enhanced leaching method: Process parameters: leaching temperature 60-80℃, liquid-solid ratio 2:1, leaching cycle 3 days; energy consumption and effect: steam heating energy consumption is 0.4 tons / ton of clinker, and lithium recovery rate is increased to 80%-85%. Disadvantages: (1) High temperature aggravates the leaching of impurities: iron and aluminum ion concentrations increase by 50%, and subsequent multi-stage chemical precipitation is required, which leads to frequent failure of ion exchange resin. Summary of the Invention
[0010] The purpose of this invention is to solve the above-mentioned problems by providing a highly efficient dynamic leaching and purification system for lithium mica clinker.
[0011] The technical solution of this application is implemented as follows: This invention provides a high-efficiency dynamic leaching and purification system for lithium mica clinker, comprising: The soaking tanks No. 1 to No. 8 are connected in sequence. The two soaking tanks that are connected to each other are connected by a first circulation pump, and each soaking tank is equipped with an internal circulation pump. A water purification tank, wherein the water purification tank is connected to each soaking tank via a first connecting conduit, and an electrically controlled valve is provided between each soaking tank and the first connecting conduit; The impurity removal tank is connected to each soaking tank via a second connecting conduit, and a second circulation pump is provided between each soaking tank and the second connecting conduit. The impurity removal tank also includes a pipe for introducing impurity removal agent and an electromagnetic unit for generating an external magnetic field.
[0012] As a further improvement, each soaking tank is 27 meters long, 9 meters wide, and 1 meter high; soaking tanks 1 to 4 are defined as the first group, and soaking tanks 5 to 8 are defined as the second group. The amount of roasting on the first day is placed into each soaking tank in the first group, and the amount of roasting on the second day is placed into each soaking tank in the second group.
[0013] As a further improvement, the system also includes: The filter press assembly is connected to the outlet of the impurity removal tank; The purification component is connected to the discharge port of the filter press component.
[0014] As a further improvement, the internal circulating liquid pump uses a flow rate Q of 100~200m³ / h. 3 A high-pressure spray pump with a flow rate of 150~250 m³ / h; the second circulation pump uses a flow rate Q of 150~250 m³ / h. 3 A high-pressure spray pump with a capacity of / h.
[0015] As a further improvement, one-third to one-half of the total liquid volume in the soaking tank is transferred to an adjacent soaking tank each day.
[0016] The present invention further provides a control method for a high-efficiency dynamic leaching and purification system for lithium mica clinker, comprising: transferring the leachate by means of a combination of a second circulation pump and gravity flow.
[0017] As a further improvement, the method of transferring leachate using a combination of a second circulation pump and gravity flow specifically includes: While controlling the second circulation pump to transfer the leachate from one soaking tank to the next soaking tank, the valves between the other soaking tanks are opened simultaneously, allowing the leachate between the other soaking tanks to flow by gravity.
[0018] As a further improvement, the method of transferring leachate using a combination of a second circulation pump and gravity flow specifically includes: During the process of controlling at least two second-stage cross-group cycles to transfer leachate from at least two soaking tanks to the next soaking tank, valves between other soaking tanks are opened to allow leachate between other soaking tanks to flow by gravity.
[0019] As a further improvement, the method of transferring leachate using a combination of a second circulation pump and gravity flow also includes: In order to extend the service life of the second circulation pump and enhance the flow efficiency between the various soaking tanks, the second circulation pump is further controlled in turn to operate sequentially.
[0020] The advantages or beneficial effects of the above technical solutions include at least the following: (1) Break through the leaching efficiency bottleneck and shorten the cycle to 4 days; To address the issues of long leaching cycles (5-7 days) and low lithium leaching rates (70%-80%) in traditional processes, a dynamic liquid flow system (internal circulation spraying + cross-group liquid transfer) is used to shorten the leaching cycle to 4 days and reduce the residual Li2O content in the residue to 0.188% (leaching rate ≥85.3%), improving efficiency by 16.66%-20% compared to traditional processes.
[0021] (2) Overcome the problem of impurity interference and simplify the subsequent purification process; To address the high purification costs caused by the leaching of fluorine, iron, and aluminum impurities, a staged impurity removal process was developed: Stage 1: Fluorine removal: Adding Ca(OH)₂ (0.5%-1.0%) combined with pH adjustment (6.5-7.0), achieving a fluorine removal rate >85%; Stage 2: Magnetized sedimentation: Applying an external magnetic field (0.5-1.2T) accelerates the flocculation of iron and aluminum impurities, improving sedimentation efficiency by 50%. Furthermore, precision filtration is included: a plate filter press (filtration accuracy ≤10μm) traps fine particles, resulting in a suspended solids content in the purified liquid <50mg / L, reducing subsequent purification costs by 40%. Li in the leachate... + With a concentration ≥13g / L, after concentration and impurity removal, it can be directly used for lithium carbonate preparation, greatly reducing subsequent purification processes and costs.
[0022] (3) Construct an intelligent control system; To address the issues of high reliance on manual labor and poor process stability, a PLC central control system is integrated to monitor and automatically adjust parameters such as liquid level, pH (4-6), and temperature (25-35℃) in real time, reducing manual intervention by 70% and improving process stability to 95%, thus providing technical support for large-scale continuous production. Attached Figure Description
[0023] The accompanying drawings illustrate exemplary embodiments of the present application and, together with the description thereof, serve to explain the principles of the present application. These drawings are included to provide a further understanding of the present application and are incorporated in and constitute a part of this specification.
[0024] Figure 1 The flowchart illustrates a method for efficient leaching and purification of lithium mica clinker provided in an embodiment of the present invention.
[0025] Figure 2The diagram shows a framework of a dynamic leaching purification system used in a high-efficiency leaching purification method for lithium mica clinker provided in an embodiment of the present invention. Detailed Implementation
[0026] Embodiments of this application will now be described in more detail with reference to the accompanying drawings. While some embodiments of this application are shown in the drawings, it should be understood that this application can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this application. It should be understood that the drawings and embodiments of this application are for illustrative purposes only and are not intended to limit the scope of protection of this application.
[0027] It should be noted that, where there is no conflict, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0028] The names of the messages or information exchanged between multiple devices in the embodiments of this application are for illustrative purposes only and are not intended to limit the scope of these messages or information.
[0029] Reference Figure 1 As shown in the figure, this embodiment of the invention provides a method for efficient leaching and purification of lithium mica clinker, including the following steps: S1, providing lithium mica clinker, wherein the particle size of the lithium mica clinker is 6~8mm, the porosity of the lithium mica clinker is greater than 40%, and the residual heat temperature of the lithium mica clinker is 50~80℃. S2, the lithium mica clinker is fed into the sequentially connected leaching tanks 1 to 8 of the dynamic leaching purification system in batches. Each leaching tank 10 adopts internal circulation enhancement, and the liquid flow covers the entire tank to eliminate dead zones. Furthermore, inter-tank liquid transfer is adopted between adjacent leaching tanks 10 to transfer the leachate to the adjacent tank group, maintaining a dynamic balance of liquid volume to improve the utilization rate of leachate. S3, when the leachate from one of the soaking tanks 10 is concentrated to Li + When the concentration is ≥13g / L, the leachate from the soaking tank 10 is transferred to the impurity removal tank 16. S4, Ca(OH)2 solution is added to the impurity removal tank 16 to adjust the pH to 6.5-7.0 for primary fluoride removal; S5, apply an external magnetic field to the impurity removal tank 16 to perform secondary magnetization sedimentation; S6 is used to filter and purify the product after secondary magnetization sedimentation.
[0030] In step S1, the lepidolite clinker is formed by mixing lepidolite with additives, followed by granulation and calcination. Specifically, the preparation method of the lepidolite clinker includes the following steps: Lithium mica ore was mixed with additives (semi-coke, Na2CO3, CaSO4) at a mass ratio of 6:1 to prepare particles with a particle size of 6~8mm. The particles are then added to a rotary kiln, and the roasting temperature of the rotary kiln is controlled at 930℃±10℃ for about 2 hours. The Li2O content in the roasted lepidolite clinker is stable at 1.28%-1.30%. In one embodiment, the Li2O content in the roasted lepidolite clinker is stable at 1.29%.
[0031] After the roasted lepidolite clinker is discharged from the kiln, it is cooled in a waste heat boiler. After the waste heat is recovered, it is directly put into soaking tank 10. The waste heat temperature of the lepidolite clinker can be maintained at 50~80℃ after the waste heat is recovered.
[0032] Preferably, steps S2-S6 are implemented using a dynamic leaching purification system. Please refer to [link to relevant documentation]. Figure 2 As shown, the dynamic leaching purification system includes: The soaking tanks 1 to 8 are connected in sequence. The two soaking tanks 10 that are connected to each other are connected by the first cross-group circulation pump 12, and each soaking tank 10 is equipped with an internal circulation pump 11. A water purification tank 14 is connected to each soaking tank 10 via a first connecting conduit 13, and an electrically controlled valve 15 is provided between each soaking tank 10 and the first connecting conduit 13. The impurity removal tank 16 is connected to each soaking tank 10 via a second connecting conduit 18, and a second circulation pump 19 is provided between each soaking tank 10 and the second connecting conduit 18; the impurity removal tank 16 also includes an impurity removal agent inlet pipe 20. The filter press assembly 21 is connected to the discharge port of the impurity removal tank 16; The purification component 22 is connected to the discharge port of the filter press component 21.
[0033] Preferably, each soaking tank 10 is 27 meters long, 9 meters wide, and 1 meter high. In one embodiment, soaking tanks 10 10 1 to 4 are defined as the first group, and soaking tanks 10 5 to 8 are defined as the second group. The amount of roasting on the first day is placed into each soaking tank 10 in the first group (about 3200 tons), and the amount of roasting on the second day is placed into each soaking tank 10 in the second group.
[0034] To facilitate subsequent automated control, each soaking tank 10 can be further equipped with a water level sensor (not shown in the figure). This sensor detects the liquid level in each soaking tank 10 and then replenishes the water through the purification tank 14 to reach the preset height. The water in the purification tank 14 is distilled water. Each soaking tank 10 can also be further equipped with various ion sensors (not shown in the figure) to acquire real-time data on F ion concentration (line fluoride ion selective electrode (ISE)), Li ion concentration (line lithium ion selective electrode (ISE)), pH value (online pH electrode), and other ion parameters in the solution. Specifically, to achieve automated control, this invention further integrates a PLC central control system, which connects to various sensors, valves, and spray pumps. This PLC central control system monitors and automatically adjusts parameters such as liquid level, pH (4-6), and various ion concentrations in real time, reducing manual intervention by 70% and improving process stability to 95%, providing technical support for large-scale continuous production.
[0035] The internal circulation pump 11 has a flow rate Q of 100~200 m³ / h. 3 A high-pressure spray pump with a spray density of 10~20 L / (m³) is used. 2 ·s), internal circulation spraying is performed, and the liquid flow covers the entire pool, thereby eliminating "dead zones". In one embodiment, the internal circulation pump 11 uses a flow rate Q of 150m³ / s. 3 A high-pressure spray pump with a spray density of 15 L / (m³) is used. 2 ·s).
[0036] The second circulating pump 19 has a flow rate Q of 150~250m³ / h. 3 A high-pressure spray pump with a flow rate of / h is used for cross-pool spraying, transferring the leachate to adjacent soaking tanks 10 to maintain dynamic balance of liquid volume and maximize the utilization rate of the leachate. In one embodiment, the second circulation pump 19 uses a flow rate Q of 200m³ / h. 3 A high-pressure spray pump with a flow rate of / h. Preferably, 1 / 3 to 1 / 2 of the total liquid volume in soaking tank 10 is transferred to an adjacent soaking tank 10 daily to maintain a dynamic balance of liquid volume and maximize the utilization rate of the leachate. In one embodiment, 1 / 2 of the total liquid volume in soaking tank 10 is transferred to an adjacent soaking tank 10 daily. It can be understood that during static or small-scale internal circulation, the liquid film Li on the particle surface... + The concentration quickly approaches saturation, the concentration boundary layer thickens, and the leaching rate decreases. Removing 1 / 3 to 1 / 2 of the liquid can instantly lower the Li content in the liquid phase. +At concentrations of 30-50%, a significant concentration gradient reforms between the solid and liquid phases, the boundary layer is torn and renewed, and a "second peak" appears in the leaching rate. Additionally, the large-scale transfer of 1 / 3 to 1 / 2 of the leaching solution dilutes the high-fluoride solution across multiple tanks, increasing the leaching rate per tank. - The peak value decreased by 25-35%, Ca(OH)2 consumption decreased by about 15%, and the scaling cycle of pipelines was extended by 1.5 to 2.5 times.
[0037] As a further improvement, in order to save energy, the leachate can be transferred by combining the second circulation pump 19 with gravity flow.
[0038] Specifically, while controlling the second circulation pump 19 to transfer the leachate from one soaking tank 10 to the next, valves between the other soaking tanks 10 are simultaneously opened, allowing the leachate in the other soaking tanks 10 to flow by gravity, thus significantly saving energy. Only one pump is used as the "starting point," while the remaining connecting valves are opened, utilizing the liquid level difference (tank depth 1 m) to allow the liquid to flow synchronously between all adjacent tanks. Actual measurements show that the 8-tank series system saves over 65% of daily electricity. Furthermore, gravity flow allows high-Li... + Liquid automatically flows to low Li + The system is filled in zones, and the flow stops when the liquid level difference is maintained at 2-3 cm. The system automatically finds its balance and does not require manual adjustment of the liquid level. For example, while controlling the second circulation pump 19 to transfer the leachate from soaking tank 10 to soaking tank 2, the valves between soaking tanks 3-8 and between soaking tank 10 10 and soaking tank 10 8 are opened at the same time, allowing the leachate in the other soaking tanks 10 to flow by gravity.
[0039] Because the disturbance force and flow rate of gravity flow between soaking tanks 10 are relatively small, in order to increase the disturbance force and flow rate between soaking tanks 10, preferably, while controlling at least two second circulation pumps 19 to transfer the leachate from one soaking tank 10 to the next soaking tank 10, the valves between other soaking tanks 10 are opened, allowing the leachate between other soaking tanks 10 to flow by gravity. For example, while controlling the second circulation pump 19 to transfer the leachate from soaking tank 10 to soaking tank 2, and while controlling the second circulation pump 19 to transfer the leachate from soaking tank 5 to soaking tank 6, the valves between soaking tanks 3-4, 7-8, and 8 and 1 are opened, allowing the leachate between other soaking tanks 10 to flow by gravity.
[0040] In other embodiments, to extend the service life of the second circulation pump 19 and enhance the flow efficiency between the various soaking pools 10, the second circulation pump 19 can be controlled to operate sequentially. Specifically, the second circulation pump 19 between soaking pool 10 and soaking pool 2 is turned on at time T1, the second circulation pump 19 between soaking pool 2 and soaking pool 3 is turned on at time T2, the second circulation pump 19 between soaking pool 3 and soaking pool 4 is turned on at time T3, and so on. The system changes from a one-time group breathing to a sequential wave-like progression, with only one channel having pump pressure at each time period, while the other valves remain open for gravity flow, but without reverse impact; the liquid phase always follows a unidirectional flow from 1 to 2 to 3 to ... to 8, eliminating high Li caused by backflow short circuits. + The liquid level in the next working pool is lowered by 3-5 cm, while the upstream pool maintains a high level. The process then rotates to the downstream pool in the next period, maintaining a level difference of 2-4 cm. The gravity-driven flow does not diminish, and no additional pumps are needed throughout the day. This "pool-by-pool rotation" transforms continuous large-scale circulation into sequential small pulses, using time-staggered timing to achieve spatial pressure differences. This further reduces power consumption, smooths concentration distribution, and eliminates short-circuit occurrences, making it a scheduling method that maintains high mass transfer with ultra-low power consumption.
[0041] Alternatively, at time T1, the second circulation pump 19 between soaking tank 10 and soaking tank 10, and between soaking tank 5 and soaking tank 10; then at time T2, the second circulation pump 19 between soaking tank 2 and soaking tank 10, and between soaking tank 7 and soaking tank 10, and so on.
[0042] It is understandable that the above treatment can greatly shorten the leaching cycle and increase the leaching rate, reducing the leaching cycle to 4 days and the lithium leaching rate to ≥85.3% (Li2O residue in the slag is reduced to 0.188%), while the lithium leaching rate of traditional leaching processes is only about 70%-80%.
[0043] In other embodiments, the impurity removal tank 16 further includes a second internal circulation pump 17 for internal circulation spraying. Both the primary defluorination and the secondary magnetization sedimentation are performed in the impurity removal tank 16.
[0044] Specifically, the primary defluorination includes: A Ca(OH)₂ solution with a mass concentration of 0.5%-1.0% is added to the impurity removal tank 16 to adjust the pH to 6.5-7.0 for primary fluoride removal. During this process, calcium ions react with fluoride ions to form calcium fluoride precipitate, thereby removing fluoride and achieving a fluoride ion removal rate greater than 85%.
[0045] Specifically, the secondary magnetization sedimentation includes: By applying an external magnetic field with an intensity of 0.5-1.2T to the impurity removal tank 16, the flocculation and sedimentation of iron and aluminum impurities can be accelerated, thereby shortening the sedimentation time by 50%.
[0046] The step of pressing and filtering the product after secondary magnetization sedimentation is implemented in the pressure filter assembly 21. Specifically, a plate filter press (filtration accuracy ≤10μm) is used to retain fine particles, and the suspended solids content of the purified liquid is <50mg / L for pressure filtration.
[0047] Example 1: Lithium mica ore was mixed with additives (semi-coke, Na2CO3, CaSO4) at a mass ratio of 6:1 (0.5:0.3:0.2) to prepare particles with a diameter of 6-8 mm. These particles were then added to a rotary kiln, and the roasting temperature was controlled at 930℃±10℃ for approximately 2 hours. Testing showed that the Li2O content in the roasted lithium mica clinker remained stable at 1.29%. After exiting the kiln, the roasted lithium mica clinker was cooled in a waste heat boiler. After waste heat recovery, it was directly fed into leaching tank 10, where the waste heat temperature was maintained at approximately 60℃. The lithium mica clinker was then leached in batches into leaching tank 10 of a dynamic leaching purification system for approximately 4 days. When the leachate from one leaching tank 10 was concentrated to a certain concentration, the leaching process was completed. + When the concentration is ≥13 g / L, the leachate from the soaking tank 10 is transferred to the impurity removal tank 16; then, Ca(OH)₂ solution is added to the impurity removal tank 16 to adjust the pH to 6.5 for primary fluoride removal; then, an external magnetic field is applied to the impurity removal tank 16 for secondary magnetization sedimentation; finally, the product after secondary magnetization sedimentation is filtered to obtain filtrate and filter residue. During the leaching process, samples of lepidolite clinker are taken and analyzed daily, as shown in Table 1.
[0048] Table 1 shows the Li₂O content and leaching rate data in lepidolite clinker.
[0049] As can be seen from Table 1, the leaching rate of the present invention in the final 4-day leaching process can reach 85.3%, which is 12.6% higher than that of the tunnel kiln process (slag Li2O, 0.35%); and 7.14% higher than that of the rotary kiln process (slag Li2O, 0.28%); and 2.46% higher than that of the high-temperature leaching method (slag Li2O, 0.22%).
[0050] Those skilled in the art should understand that the above embodiments are merely for illustrative purposes and are not intended to limit the scope of this application. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of this application.
Claims
1. A high-efficiency dynamic leaching and purification system for lithium mica clinker, characterized in that, include: Soaking tanks 1 to 8 are connected in sequence, and soaking tank 8 is connected to soaking tank 1 to form a loop. The two soaking tanks that are connected to each other are connected by a first circulation pump, and an internal circulation pump is installed in each soaking tank. A water purification tank, wherein the water purification tank is connected to each soaking tank via a first connecting conduit, and an electrically controlled valve is provided between each soaking tank and the first connecting conduit; The impurity removal tank is connected to each soaking tank via a second connecting conduit, and a second circulation pump is provided between each soaking tank and the second connecting conduit. The impurity removal tank also includes a Ca(OH)2 impurity removal agent inlet pipe and an electromagnetic unit for generating an external magnetic field.
2. The high-efficiency dynamic leaching and purification system for lithium mica clinker according to claim 1, characterized in that: Each soaking tank is 27 meters long, 9 meters wide, and 1 meter high. Soaking tanks 1 to 4 are defined as the first group, and soaking tanks 5 to 8 are defined as the second group. The amount of roasting on the first day is placed into each soaking tank in the first group, and the amount of roasting on the second day is placed into each soaking tank in the second group.
3. The high-efficiency dynamic leaching and purification system for lithium mica clinker according to claim 1, characterized in that: Also includes: The filter press assembly is connected to the outlet of the impurity removal tank; The purification component is connected to the discharge port of the filter press component.
4. The high-efficiency dynamic leaching and purification system for lithium mica clinker according to claim 1, characterized in that: The internal circulating pump has a flow rate Q of 100~200 m³ / h. 3 A high-pressure spray pump with a flow rate of 150~250 m³ / h; the second circulation pump uses a flow rate Q of 150~250 m³ / h. 3 A high-pressure spray pump with a capacity of / h.
5. The high-efficiency dynamic leaching and purification system for lithium mica clinker according to claim 4, characterized in that: Each day, transfer 1 / 3 to 1 / 2 of the total liquid volume in the soaking tank to an adjacent soaking tank.
6. The control method for the high-efficiency dynamic leaching and purification system of lithium mica clinker according to claim 5, characterized in that: The leachate is transferred using a combination of a second circulation pump and gravity flow.
7. The control method for the high-efficiency dynamic leaching and purification system of lithium mica clinker according to claim 6, characterized in that: The method of transferring leachate using a combination of a second circulation pump and gravity flow specifically includes: While controlling the second circulation pump to transfer the leachate from one soaking tank to the next soaking tank, the valves between the other soaking tanks are opened simultaneously, allowing the leachate between the other soaking tanks to flow by gravity.
8. The control method for the high-efficiency dynamic leaching and purification system of lithium mica clinker according to claim 6, characterized in that: The method of transferring leachate using a combination of a second circulation pump and gravity flow specifically includes: During the process of controlling at least two second-stage cross-group cycles to transfer leachate from at least two soaking tanks to the next soaking tank, valves between other soaking tanks are opened to allow leachate between other soaking tanks to flow by gravity.
9. The control method for the high-efficiency dynamic leaching and purification system of lithium mica clinker according to claim 1, characterized in that: Each soaking tank is further equipped with a water level sensor, various ion sensors, and a PLC central control system to achieve automated control.