Lithium-based metal preparation system and method

Abstract

The invention discloses a lithium-based metal preparation system and method. The lithium-based metal preparation system comprises a raw material processing assembly, a collecting tank and a vacuum system, the raw material processing assembly comprises a heating assembly, a driving assembly and a barrel; a feeding hole and a discharging hole are formed in the cylinder body, and the cylinder body is arranged on the bracket; the heating assembly is arranged around the circumferential direction of the cylinder body; the driving assembly is in transmission connection with the barrel body, or the action end of the driving assembly extends into the barrel body; the height of the discharging port is larger than that of a machining upper limit mark point of the raw material machining assembly, and a cooling system is arranged at the discharging port. A collecting opening and a discharging opening are formed in the collecting tank, the collecting opening is communicated with the discharging opening through the cooling system, and the vacuumizing end of the vacuum system is communicated with the discharging opening. When the lithium-based metal preparation system is used for preparing lithium-based metal, the driving assembly is used for driving the barrel to act or vibrating and stirring raw materials in the barrel, so that the raw materials are heated more uniformly, and the preparation efficiency of the lithium-based metal is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of material chemical engineering, and in particular relates to a lithium-based metal preparation system and method. Background Art

[0002] In the traditional method, when lithium-based metals are prepared by thermal reduction, the process is as follows:

[0003] a. Mechanically crush, stir and mix the raw material lithium carbonate and auxiliary material calcium oxide;

[0004] b. Granulate the raw and auxiliary materials after mixing;

[0005] c. putting the particles into a vacuum thermal decomposition furnace for reaction to obtain a lithium oxide raw material immersed in auxiliary materials such as calcium oxide;

[0006] d. further adding a stoichiometric ratio of ferrosilicon reducing agent to the mixed decomposition material containing lithium oxide;

[0007] e. Then the materials are mixed, granulated and put into a vacuum thermal reduction furnace for high-temperature reaction to obtain lithium-based metal in a crystallizer.

[0008] In the traditional process, when thermal decomposition generates lithium oxide, the weight of auxiliary materials accounts for more than 80%. Obviously, its thermal efficiency in the preparation of lithium oxide is significantly low. In addition, in the existing thermal reduction furnace, the heating method is resistance heating, gas heating or coal heating, and an insulating outer wall with excellent thermal insulation performance is required. On the one hand, the heating uniformity is difficult to ensure. On the other hand, a long cooling process is required to complete the thermal reduction, remove the crystallizer and clean the slag in the reduction furnace, which seriously hinders the rapid and continuous progress of the production process and leads to low efficiency in the preparation of lithium-based metals.

[0009] In addition, during the thermal reduction process, the materials in the thermal reduction furnace are in a static state, which hinders the thermal reduction reaction from proceeding sufficiently and quickly, and also hinders the diffusion of the reduced lithium-based metal vapor from leaving the reduction furnace and entering the crystallizer. Summary of the invention

[0010] In order to solve the above technical problems, the present invention provides a lithium-based metal preparation system on the one hand to solve the technical problems that the heating uniformity of the vacuum thermal decomposition furnace in the prior art is difficult to ensure and a long cooling process is required during cleaning, resulting in reduced lithium-based metal preparation efficiency.

[0011] The technical solution adopted to achieve the purpose of the present invention is:

[0012] A lithium-based metal preparation system includes a raw material processing assembly, a collection tank, and a vacuum system;

[0013] The raw material processing assembly includes a heating assembly, a driving assembly and a barrel; the barrel is a circular cylindrical structure, and is provided with a feed port and a discharge port, and the barrel is arranged on a bracket; the heating assembly is arranged around the circumference of the barrel; the driving assembly is in transmission connection with the barrel, or the action end of the driving assembly penetrates into the interior of the barrel to stir the material inside the barrel; the height of the discharge port is greater than the height of the upper limit mark point of the raw material processing assembly, and a cooling system is arranged at the discharge port;

[0014] The collecting tank is provided with a collecting port and a discharging port. The collecting port is communicated with the discharging port through the cooling system, and the vacuuming end of the vacuum system is communicated with the discharging port.

[0015] In order to better realize the present invention, further optimization is made in the above structure, wherein the cooling system includes a cooling pipeline and a connecting flange;

[0016] The connecting flange is arranged at the discharge port, and the collecting port is connected with the discharge port through the connecting flange;

[0017] The cooling pipeline is arranged around the connecting flange.

[0018] In order to better realize the present invention, further optimization is made in the above structure, which also includes a control system;

[0019] The raw material processing assembly and the vacuum system are both in signal connection with the control system.

[0020] In order to better realize the present invention, further optimization is made in the above structure, the collecting tank is a conical structure, the collecting port and the discharge port are respectively arranged at the small end of the collecting tank and the large end of the collecting tank, and the axis of the collecting port is parallel to the axis of the discharge port.

[0021] In order to better implement the present invention, further optimization is made in the above structure, and the axis of the discharge port is located directly above the axis of the collection tank.

[0022] On the other hand, the present invention also provides a method for preparing lithium-based metals, the method being implemented using the above-mentioned lithium-based metal preparation system, the method comprising the following steps:

[0023] uniformly mixing lithium oxide and a corresponding reducing agent to form a mixture;

[0024] Mechanically compacting and granulating the mixed precursor materials to form mixed particles, and after granulation, adding the mixed particles into a vacuum system;

[0025] Add the mixture into the raw material processing assembly, start the vacuum system, and make the vacuum degree in the cylinder reach 0.01 Pa;

[0026] Starting the heating component in the raw material processing component to make the temperature of the mixed particles in the cylinder reach 800-1300° C., and at the same time, stirring the mixed particles to make the lithium oxide react with the corresponding reducing agent to produce metallic lithium in steam;

[0027] The vapor of metallic lithium enters the collecting tank through the cooling system under the action of the vacuum system, and is deposited in the collecting tank to form liquid and / or solid metallic lithium;

[0028] After the metallic lithium is cooled to room temperature, a protective gas is filled into the collection tank, and the metallic lithium is taken out through an oil bath; at the same time, the cylinder is taken out from the heating assembly, and when the temperature in the cylinder is lowered to room temperature, the solid waste formed by the reaction in the cylinder is taken out.

[0029] In order to better realize the present invention, further optimization is made in the above method, and the molar ratio of the lithium oxide to the corresponding reducing agent is 1:1-1.5.

[0030] In order to better realize the present invention, the above method is further optimized by adding an auxiliary agent that accelerates and stabilizes the reduction process to the lithium oxide and the reducing agent before granulation.

[0031] It can be seen from the above technical scheme that the lithium-based metal preparation system provided by the present invention utilizes a driving component to drive the cylinder to move, or vibrate and stir the raw materials inside the cylinder when preparing lithium-based metals, so that the raw materials are heated more evenly, thereby improving the preparation efficiency of lithium-based metals.

[0032] On the other hand, the heating component in the present invention is an induction heating coil, and its heating efficiency and heating rate are greatly improved; and the cylinder can be separated from the heating component. When cleaning the cylinder, there will be no slow heat dissipation due to the cylinder being wrapped by the heating component, which will cause the waiting time to be extended and the production efficiency to be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic structural diagram of a lithium-based metal preparation system (horizontal) provided by the present invention;

[0034] Figure 2 A schematic structural diagram of a lithium-based metal preparation system (vertical) provided by the present invention.

[0035] Description of reference numerals:

[0036] 1-raw material processing component, 11-heating component, 12-driving component, 13-barrel;

[0037] 2- Collection tank;

[0038] 3- Vacuum system;

[0039] 4- Cooling system. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to which the present invention belongs to understand the present invention more clearly, the technical solution of the present invention is described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0041] In an embodiment of the present invention, the lithium-based metal preparation system includes a raw material processing component 1, a collection tank 2 and a vacuum system 3; wherein,

[0042] The raw material processing assembly 1 includes a heating assembly 11, a driving assembly 12 and a barrel 13; in this embodiment, the barrel 13 is a circular cylindrical structure, and a feed port and a discharge port are arranged on the barrel 13. The barrel 13 is horizontally placed on the bracket, that is, a horizontal barrel 13 structure, and the feed port and the discharge port are respectively arranged at both ends of the barrel 13, see Figure 1 ;

[0043] The heating component 11 is arranged around the circumference of the cylinder 13. In this embodiment, the heating component 11 is an induction heating coil, which has high heating efficiency and heating rate, and can effectively improve the processing efficiency;

[0044] The driving assembly 12 is in transmission connection with the cylinder 13, and is used to drive the cylinder 13 to rotate on the bracket;

[0045] The collecting tank 2 is provided with a collecting port and a discharging port. The collecting port is connected with the discharging port through the cooling system 4. The vacuuming end of the vacuum system 3 is connected with the discharging port.

[0046] When the lithium-based metal preparation system is used to prepare lithium-based metal, lithium oxide can be used as a raw material and ferrosilicon alloy can be used as a reducing agent. The two can be simply mechanically mixed, and ball milling is often used for mixing. Further, either pure powder is used as a raw material, or after granulation, it is added to the cylinder 13 of the raw material processing component 1;

[0047] Then the vacuum system 3 can be started to make the vacuum degree inside the cylinder 13 reach above 0.01Pa;

[0048] The heating assembly 11 is then started to heat the material (raw material and reducing agent mixed to form the material) inside the cylinder 13 to 800-1300° C. At this time, the lithium oxide reacts with the ferrosilicon alloy to generate solid iron oxide, silicon oxide and steam metal lithium, and the steam metal lithium is sucked into the collection tank 2 under the action of the vacuum system 3;

[0049] The steam of lithium metal needs to pass through the cooling system 4 when it moves to the collecting tank 2, and the temperature of the steam of lithium metal is reduced to room temperature, so that the steam of lithium metal entering the collecting tank 2 is cooled to form a liquid phase and / or a solid phase and is deposited in the collecting tank 2;

[0050] After the reaction in the cylinder 13 is completed, the heating assembly 11 and the vacuum system 3 are stopped in sequence, and a protective gas (argon or nitrogen) is filled into the collecting tank 2, and then the collecting tank 2 is opened, and the metallic lithium in the collecting tank 2 is taken out by oil bath; in addition, the oxides generated by the reaction in the cylinder 13 are emptied for standby use, so as to prepare for the next preparation of lithium-based metal. Preferably, the cylinder 13 can be removed from the heating assembly 11. When it is necessary to empty the oxides generated by the reaction in the cylinder 13, the cylinder 13 can be removed from the heating assembly 11 to avoid the situation where the cylinder 13 is wrapped by the heating assembly 11 and the heat dissipation is slow, resulting in an extended waiting time and a reduction in production efficiency.

[0051] It should be noted that the above-mentioned vacuum system 3 is a three-stage vacuum system 3 composed of a mechanical pump, a Rhodes pump and a diffusion pump, so that it can achieve a vacuum of 0.01 Pa to meet the preparation requirements of lithium-based metals.

[0052] In some embodiments, the cylinder 13 can also be a vertical structure, see Figure 2 That is, the cylinder 13 is placed vertically on the bracket, the heating component 11 is arranged around the circumference of the cylinder 13, the feed port and the discharge port are both arranged at the end of the cylinder 13 away from the bracket, and the actuating end of the driving component 12 is provided with a stirring device and penetrates into the cylinder 13 so that it can stir the material inside the cylinder 13;

[0053] When heating the material, the driving component 12 can be started to stir the material through the driving component 12 so that the material is heated more evenly, thereby improving the preparation efficiency of the lithium-based metal.

[0054] In addition, the driving assembly 12 can also be a vibration device, the action end of the vibration device is connected to the cylinder 13 in a transmission manner to drive the cylinder 13 to vibrate, so that the material in the cylinder 13 is heated more evenly.

[0055] In some embodiments, the cooling system 4 includes a cooling pipeline and a connecting flange; wherein,

[0056] The connecting flange is arranged at the discharge port, and the collecting port is connected with the discharge port through the connecting flange;

[0057] The cooling pipeline is wound around the connecting flange so that the metallic lithium in the steam passing through the connecting flange can exchange heat with the cooling pipeline, so that the temperature of the metallic lithium in the steam can drop to room temperature and form liquid and / or solid phase deposition in the collecting tank 2.

[0058] In some embodiments, a cooling water channel may be opened inside the connecting flange, and a cooling pipeline may be arranged in the cooling water channel so that cooling water can enter the cooling water channel to exchange heat with the metallic lithium in the steam to improve the heat exchange effect.

[0059] In some embodiments, the lithium-based metal preparation system further includes a control system;

[0060] The raw material processing assembly 1 and the vacuum system 3 are both connected to the control system signal, and the staff can control the opening / closing of the raw material processing assembly 1 and the vacuum system 3 through the control system to make the operation of the lithium-based metal preparation system simpler and more convenient.

[0061] It should be noted that the heating component 11 and the driving component 12 in the raw material processing component 1 can be controlled and operated by a control system, so that the operation of the lithium-based metal preparation system is simpler and more convenient.

[0062] In some embodiments, the above-mentioned collecting tank 2 is a conical structure, and the collecting port and the discharge port are respectively arranged at the small end of the collecting tank 2 and the large end of the collecting tank 2, the axis of the collecting port is parallel to the axis of the discharge port, and the axis of the discharge port is located directly above the axis of the collecting tank 2.

[0063] Preferably, the small end of the above-mentioned collecting tank 2 extends through the cooling system 4 into the cylinder 13, and the large end of the collecting tank 2 is located outside the cylinder 13, so that the height of the collecting part of the collecting tank 2 is lower than the height of the discharge port, so that it can store liquid and / or solid metallic lithium.

[0064] Based on the above-mentioned lithium-based metal preparation system, the present invention also provides a lithium-based metal preparation method, which is implemented using the above-mentioned lithium-based metal preparation system, and the method comprises the following steps:

[0065] uniformly mixing lithium oxide and a corresponding reducing agent to form a mixture;

[0066] The mixed precursor materials are mechanically compacted and granulated to form mixed granules, and after granulation, the mixed granules are added to the raw material processing component 1;

[0067] Start the vacuum system 3 to make the vacuum degree in the cylinder 13 reach 0.01Pa;

[0068] The heating component 11 in the raw material processing component 1 is started to make the temperature of the mixture in the cylinder 13 reach 800-1300° C. At the same time, the mixed particles are stirred to make the lithium oxide react with the corresponding reducing agent to produce metallic lithium in steam, and the reaction time is 1-24 hours;

[0069] The vapor of metallic lithium enters the collecting tank 2 through the cooling system 4 under the action of the vacuum system 3, and is deposited in the collecting tank 2 to form metallic lithium;

[0070] After the metallic lithium is cooled to room temperature, a protective gas is filled into the collection tank 2. After the furnace temperature drops to room temperature, the collection tank 2 is removed and placed in an argon-protected glove box. The collection tank 2 is heated to 200-300°C in a paraffin oil environment to melt the metallic lithium in the collection tank 2 and float on the surface of the paraffin oil. The metallic lithium in the molten liquid state is introduced into a special sealed container for collection, thus completing the preparation of metallic lithium. At the same time, the cylinder 13 is taken out of the heating assembly 11. When the temperature in the cylinder 13 drops to room temperature, the solid waste formed by the reaction in the cylinder 13 is taken out to prepare for the next processing of lithium-based metals. Repeating the above steps can continuously prepare lithium-based metals.

[0071] In some embodiments, the molar ratio of lithium oxide to the corresponding reducing agent is 1:1-1.5.

[0072] It should be noted that in the raw material formula, in addition to lithium oxide, magnesium oxide, aluminum oxide, zinc oxide or other metal oxides can also be added to achieve the co-reduction preparation of lithium magnesium, lithium aluminum, lithium zinc, lithium magnesium aluminum or other two or more alloys;

[0073] In the above formula, an auxiliary agent that accelerates and stabilizes the reduction process, such as calcium oxide, magnesium fluoride and other materials, can also be added. In this embodiment, the above formula refers to lithium oxide and a reducing agent, that is, before granulation, adding an auxiliary agent to lithium oxide and a reducing agent can effectively accelerate and stabilize the reduction process.

[0074] Through the above embodiments, the present invention has the following beneficial effects or advantages:

[0075] 1) When preparing lithium-based metal, the lithium-based metal preparation system uses the driving assembly 12 to drive the cylinder 13 to move, or stir the raw materials inside the cylinder 13, so that the raw materials are heated more evenly, thereby improving the preparation efficiency of lithium-based metal.

[0076] 2) The above-mentioned heating component 11 is an induction heating coil, and its heating efficiency and heating rate are greatly improved; and the cylinder 13 can be separated from the heating group 11. When cleaning the cylinder 13, there will be no slow heat dissipation due to the cylinder 13 being wrapped by the heating component 11, which will cause the waiting time to be extended and the production efficiency to be reduced, thereby improving the processing efficiency of lithium-based metals.

[0077] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0078] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A lithium-based metal preparation system, characterized in that: It comprises a raw material processing component (1), a collecting tank (2) and a vacuum system (3); The raw material processing component (1) comprises a heating component (11), a driving component (12) and a barrel (13); the barrel (13) is a circular cylindrical structure, and is provided with a feed port and a discharge port, and the barrel (13) is arranged on a bracket; the heating component (11) is arranged around the circumference of the barrel (13); the driving component (12) is connected to the barrel (13) in a transmission manner, or the action end of the driving component (12) penetrates into the interior of the barrel (13) to stir the material inside the barrel (13); the height of the discharge port is greater than the height of the upper processing limit mark point of the raw material processing component (1), and a cooling system (4) is arranged at the discharge port; The collecting tank (2) is provided with a collecting port and a discharging port, the collecting port is connected to the discharging port through the cooling system (4), and the vacuuming end of the vacuum system (3) is connected to the discharging port.

2. The lithium-based metal preparation system according to claim 1, characterized in that: The cooling system (4) comprises a cooling pipeline and a connecting flange; The connecting flange is arranged at the discharge port, and the collecting port is connected with the discharge port through the connecting flange; The cooling pipeline is wound around the connecting flange; or, the cooling pipeline is arranged in the connecting flange.

3. The lithium-based metal preparation system according to claim 2, characterized in that: Also includes control systems; The raw material processing component (1) and the vacuum system (3) are both connected to the control system signal.

4. The lithium-based metal preparation system according to claim 3, characterized in that: The collecting trough (2) is a conical structure, the collecting port and the discharge port are respectively arranged at the small end of the collecting trough (2) and the large end of the collecting trough (2), and the axis of the collecting port is parallel to the axis of the discharge port.

5. The lithium-based metal preparation system according to claim 4, characterized in that: The axis of the discharge port is located directly above the axis of the collecting tank (2).

6. A method for preparing a lithium-based metal, characterized in that: The method is implemented using the lithium-based metal preparation system according to any one of claims 1 to 5, and the method comprises the following steps: uniformly mixing lithium oxide and a corresponding reducing agent to form a mixture; Mechanically compacting and granulating the mixed precursor materials to form mixed granules, and after granulation, adding the mixed granules to the raw material processing component (1); Add the mixture into the barrel (13) of the raw material processing assembly (1), start the vacuum system (3), and make the vacuum degree in the barrel (13) reach 0.01 Pa; Starting the heating component (11) in the raw material processing component (1) to make the temperature of the mixed particles in the cylinder (13) reach 800-1300° C., and at the same time, stirring the mixed particles to make the lithium oxide react with the corresponding reducing agent to produce steam-forming metallic lithium; The vapor of metallic lithium enters the collecting tank (2) through the cooling system (4) under the action of the vacuum system (3), and is deposited in the collecting tank (2) to form liquid and / or solid metallic lithium; After the metallic lithium is cooled to room temperature, a protective gas is filled into the collection tank (2) and the metallic lithium is taken out through an oil bath; at the same time, the cylinder (13) is taken out from the heating component (11), and when the temperature in the cylinder (13) drops to room temperature, the solid waste formed by the reaction in the cylinder (13) is taken out.

7. The method for preparing lithium-based metal according to claim 6, characterized in that: The molar ratio of the lithium oxide to the corresponding reducing agent is 1:1-1.

5.

8. The method for preparing lithium-based metal according to claim 6, characterized in that: Before granulation, an auxiliary agent having the function of accelerating and stabilizing the reduction process is added to the lithium oxide and the reducing agent.

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