System for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide

Abstract

The utility model relates to the technical field of lithium carbonate production, and aims to solve the problems that the impurity removal effect cannot meet the purity requirement of battery-grade lithium carbonate and large energy consumption and high cost are easily caused when lithium carbonate is produced from lithium hydroxide in the prior art. The utility model provides a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide. The system comprises a redissolution mechanism, a first carbonization mechanism, a second carbonization mechanism and a separation mechanism, the redissolution mechanism is communicated with the first carbonization mechanism; the first carbonization mechanism is communicated with the separation mechanism; the first carbonization mechanism is communicated with the second carbonization mechanism; the second carbonization mechanism is communicated with the hydrogenation separation mechanism; the hydrogenation separation mechanism is communicated with the thermal analysis structure; according to the system for producing the battery-grade lithium carbonate from the industrial-grade lithium hydroxide, provided by the utility model, the purity of the lithium carbonate is improved so as to meet the battery-grade requirement, and the energy consumption and the production cost are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium carbonate production, and in particular to a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide. Background Art

[0002] When industrial-grade lithium hydroxide is used to produce battery-grade lithium carbonate, silicon in the industrial-grade lithium hydroxide is the main impurity that affects the purity. In order to improve the purity of the produced lithium carbonate to meet the battery-grade requirements, in the prior art, separation and purification methods such as filtration, fine filtration, and screening are usually used to further purify the produced lithium carbonate.

[0003] For example, a process for directly producing battery-grade lithium carbonate using lithium hydroxide circulating mother liquor disclosed in publication number CN117361591A, wherein the carbonized lithium carbonate mixture is vibrated and separated by a vibrating screen machine to separate coarse particles, which is used to remove impurities with excessively large particles, so as to improve the purity of the lithium carbonate and obtain a lithium carbonate mixture with a higher purity. The obtained lithium carbonate mixture with a higher purity is injected into a centrifuge for centrifugal separation to completely separate solids and liquids to obtain solid lithium carbonate;

[0004] However, the impurity removal effect of only screening and centrifugation cannot reach the required level of battery-grade lithium carbonate;

[0005] Based on the above description, there is an urgent need for a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide with high impurity removal efficiency and low energy consumption. Utility Model Content

[0006] The utility model aims to provide a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide, aiming to solve the technical problems that the existing lithium hydroxide production of lithium carbonate has impurity removal effect that fails to meet the purity requirements of battery-grade lithium carbonate and easily causes high energy consumption and high cost.

[0007] The embodiments of the present invention are implemented by the following technical solutions:

[0008] A system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide, comprising a re-dissolution mechanism, a first carbonization mechanism, a second carbonization mechanism and a separation mechanism; the re-dissolution mechanism is connected to the first carbonization mechanism; the first carbonization mechanism is connected to the separation mechanism; the first carbonization mechanism is connected to the second carbonization mechanism; the second carbonization mechanism is connected to the hydrogenation separation mechanism; the hydrogenation separation mechanism is connected to a thermal separation structure.

[0009] Preferably, the separation mechanism comprises a tank body and a filter assembly; the filter assembly is disposed on the top of the tank body; and the bottom of the tank body is connected to the second carbonization mechanism.

[0010] Preferably, the filter assembly comprises a lifting member and a stirring member; the lifting member is penetrated through the top interior of the tank body and is extended and connected to the stirring member.

[0011] Preferably, the lifting member comprises a lifting rod and a screen basket; one end of the lifting rod penetrates into the top interior of the tank body and is connected to the screen basket; the screen basket is connected to the inner wall of the tank body through a connecting assembly.

[0012] Preferably, the connecting assembly includes a slot plate and a sliding member; the slot plate is arranged on the inner wall of the tank body; one end of the sliding member is embedded in the slot cavity of the slot plate; the other end of the sliding member is connected to the screen basket; one end of the lifting rod passes through the screen basket and is rotatably connected to the screen basket.

[0013] Preferably, the screen basket is provided with an outer edge plate; and one end of the sliding member away from the slot plate is connected to the bottom of the outer edge plate.

[0014] Preferably, the stirring member comprises a plurality of stirring paddles; the stirring paddles are erected on the outer edge of the sieve basket.

[0015] The technical solution of the embodiment of the utility model has at least the following advantages and beneficial effects:

[0016] The utility model provides a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide. Most of the solid impurities in the industrial-grade lithium hydroxide are enriched and separated from a first-stage carbonization mother liquor through a first carbonization mechanism, and the separated mother liquor is further fully carbonized in a second stage. After the second-stage carbonization, thermal analysis is performed, which not only improves the purity of the lithium carbonate to meet the battery-grade requirements, but also reduces energy consumption and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a system schematic diagram of the utility model;

[0019] Figure 2 for Figure 1 The structural diagram of the separation mechanism;

[0020] Figure 3 for Figure 2 A magnified view of the local structure A in the middle;

[0021] Figure 4 for Figure 2 Exploded view of the local structure.

[0022] Icons: 1-redissolution mechanism, 2-first carbonization mechanism, 3-second carbonization mechanism, 4-separation mechanism, 41-tank body, 42-filtration assembly, 421-lifting member, 4211-lifting rod, 4212-sieve basket, 422-stirring member, 4221-stirring paddle, 5-connecting assembly, 51-trough plate, 52-sliding member, 6-hydrogenation separation mechanism, 7-thermal analysis mechanism. DETAILED DESCRIPTION

[0023] Example 1

[0024] See also Figures 1 to 4 The utility model provides the following technical solutions: a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide, which is suitable for the production of high-purity lithium carbonate.

[0025] Specifically, Figure 1 and Figure 2 As shown, a system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide includes a re-dissolution mechanism 1, a first carbonization mechanism 2, a second carbonization mechanism 3 and a separation mechanism 4; the re-dissolution mechanism 1 is connected to the first carbonization mechanism 2; the first carbonization mechanism 2 is connected to the separation mechanism 4; the first carbonization mechanism 2 is connected to the second carbonization mechanism 3; the second carbonization mechanism 3 is connected to the hydrogenation separation mechanism 6; the hydrogenation separation mechanism 6 is connected to the thermal separation structure 7.

[0026] In this embodiment, the re-dissolution mechanism 1, the first carbonization mechanism 2, and the first carbonization mechanism 2 and the thermal separation structure 7 all adopt containers such as reaction towers and reactors commonly used in the chemical industry; the hydrogenation separation mechanism 6 has the same structure as the separation mechanism 4; specifically, the first carbonization mechanism 2 includes a series of carbonization reaction towers, and the second carbonization mechanism 3 includes a series of carbonization reaction towers; after the industrial-grade lithium hydroxide is dissolved in the re-dissolution mechanism 1, it is introduced into the first carbonization mechanism 2, and carbon dioxide is introduced into the first carbonization mechanism 2 to carry out a carbonization. After a carbonization, a carbonized slurry is obtained, and the slurry is transferred to the separation mechanism 4 for separation to obtain a carbonized mother liquor. The carbonized mother liquor is again sent to the second carbonization mechanism 3 for sufficient carbonization to obtain a two-stage carbonized mother liquor. The mother liquor is transported to the hydrogenation separation mechanism 6 for hydrogenation, and the lithium carbonate is hydrogenated into lithium bicarbonate, and the soluble lithium bicarbonate is further separated from the solid impurities. After separation, the lithium bicarbonate is further converted back into high-purity lithium carbonate through the thermal separation mechanism 7.

[0027] In this embodiment, solid impurities such as silicon are enriched by the separation mechanism 4 and separated from the mother liquor carbonized at one end, so that most of the impurities in the industrial-grade lithium hydroxide can be separated, thereby reducing the energy consumption when hydrogenation-thermal separation is used after the second-stage carbonization, thereby improving the purity of lithium carbonate and reducing production costs.

[0028] Specifically, Figures 2 to 4 As shown, the separation mechanism 4 includes a tank body 41 and a filter assembly 42; the filter assembly 42 is arranged at the top of the tank body 41; and the bottom of the tank body 41 is connected to the second carbonization mechanism 3. The filter assembly 42 includes a lifting member 421 and a stirring member 422; the lifting member 421 is arranged inside the top of the tank body 41 and is extended to be connected with the stirring member 422. The lifting member 421 includes a lifting rod 4211 and a screen basket 4212; one end of the lifting rod 4211 penetrates into the top of the tank body 41 and is connected to the screen basket 4212; the screen basket 4212 is connected to the inner wall of the tank body 41 through the connecting assembly 5.

[0029] In this embodiment, the lifting rod 4211 is an electric lifting rod, and a rotating shaft is provided at its end, which is rotatably connected to the screen basket 4212 through the rotating shaft. The stirring member 422 includes a plurality of stirring paddles 4221; the stirring paddles 4221 are vertically arranged on the outer edge of the screen basket 4212; the screen basket 4212 is lowered to an appropriate height by the lifting rod 4211, and the screen basket 4212 is further rotated to rotate the plurality of stirring paddles 4221 to promote further carbonization inside the tank body 41. After carbonization, the slurry is separated to obtain a section of carbonized mother liquor, and the mother liquor is transferred to the second carbonization mechanism 3 for further carbonization, while the enriched solid impurities and part of the lithium carbonate are retained in the screen basket 4212, and the screen basket 4212 is extracted to transfer the material out for low-energy, high-purity lithium element recovery treatment.

[0030] Specifically, Figure 3 and Figure 4 As shown, the connection assembly 5 includes a slot plate 51 and a sliding member 52; the slot plate 51 is arranged on the inner side wall of the tank body 41; one end of the sliding member 52 is embedded in the slot cavity of the slot plate 51; the other end of the sliding member 52 is connected to the screen basket 4212; one end of the lifting rod 4211 penetrates into the screen basket 4212 and is rotatably connected to the screen basket 4212. The screen basket 4212 is provided with an outer edge plate; one end of the sliding member 52 away from the slot plate 51 is connected to the bottom of the outer edge plate.

[0031] In this embodiment, in order to facilitate the removal of the sieve basket 4212, the sliding member 52 is embedded in the slot plate 51. Specifically, the outer edge plate of the sieve basket 4212 is a ring plate, and the slot plate 51 is also a ring plate and a ring groove is provided in the middle of the plate body for the sliding member 52 to be embedded; the sliding member 52 is a ring block that matches the ring groove of the slot plate 51, and then the sieve basket 4212 is placed on the slot plate 51, and the sieve basket 4212 and the stirring paddle 5221 are rotated in conjunction with the rotating shaft.

[0032] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide, comprising a re-dissolving mechanism (1) and a first carbonization mechanism (2), characterized in that: It also includes a second carbonization mechanism (3) and a separation mechanism (4); the re-dissolution mechanism (1) is connected to the first carbonization mechanism (2); the first carbonization mechanism (2) is connected to the separation mechanism (4); the first carbonization mechanism (2) is connected to the second carbonization mechanism (3); the second carbonization mechanism (3) is connected to the hydrogenation separation mechanism (6); the hydrogenation separation mechanism (6) is connected to the thermal separation structure (7).

2. The system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide according to claim 1, characterized in that: The separation mechanism (4) comprises a tank body (41) and a filter assembly (42); the filter assembly (42) is arranged at the top of the tank body (41); and the bottom of the tank body (41) is connected to the second carbonization mechanism (3).

3. The system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide according to claim 2, characterized in that: The filter assembly (42) comprises a lifting member (421) and a stirring member (422); the lifting member (421) is disposed inside the top of the tank body (41) and is extended to be connected to the stirring member (422).

4. The system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide according to claim 3, characterized in that: The lifting member (421) comprises a lifting rod (4211) and a screen basket (4212); one end of the lifting rod (4211) penetrates into the top interior of the tank body (41) and is connected to the screen basket (4212); the screen basket (4212) is connected to the inner side wall of the tank body (41) via a connecting assembly (5).

5. The system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide according to claim 4, characterized in that: The connecting assembly (5) comprises a slot plate (51) and a sliding member (52); the slot plate (51) is arranged on the inner side wall of the tank body (41); one end of the sliding member (52) is embedded in the slot cavity of the slot plate (51); the other end of the sliding member (52) is connected to the sieve basket (4212); one end of the lifting rod (4211) penetrates into the sieve basket (4212) and is rotatably connected to the sieve basket (4212).

6. The system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide according to claim 5, characterized in that: The sieve basket (4212) is provided with an outer edge plate; one end of the sliding member (52) away from the slot plate (51) is connected to the bottom of the outer edge plate.

7. The system for producing battery-grade lithium carbonate from industrial-grade lithium hydroxide according to any one of claims 4 to 6, characterized in that: The stirring member (422) includes a plurality of stirring paddles (4221); the stirring paddles (4221) are vertically arranged on the outer edge of the sieve basket (4212).

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