A gas-liquid reaction kettle for preparing lithium carbonate

Abstract

The present application relates to a kind of gas-liquid reaction kettle for preparing lithium carbonate, belong to gas-liquid reaction kettle preparation technical field.The reaction kettle includes kettle body, kettle cover and kettle bottom;In the reaction kettle, baffle is arranged close to the inner wall of kettle body;The upper end of baffle is fixedly connected with kettle cover, and the two side edges of baffle are fixedly connected with the inner wall of kettle body, to prevent gas leakage;The lower end of baffle is spaced apart from the inner wall of kettle bottom by a distance;At least one liquid inlet pipe and at least one gas inlet pipe are provided on the kettle cover, and a gas release valve is also provided on the kettle cover;The gas release valve is installed between the baffle and the kettle body close to the baffle.During the preparation of lithium carbonate, the gas inlet pipe is not blocked, and the utilization rate of carbon dioxide is high.

Description

Technical Field

[0001] This invention relates to a gas-liquid reactor for preparing lithium carbonate, belonging to the field of gas-liquid reactor preparation technology. Background Technology

[0002] Currently, a common method for preparing lithium carbonate involves introducing carbon dioxide into a lithium hydroxide solution, followed by filtration, washing, and drying to obtain lithium carbonate. The commonly used apparatus is a gas-liquid reactor. In existing gas-liquid reactors, during the reaction of carbon dioxide with the lithium hydroxide solution, the resulting lithium carbonate crystals adhere tightly to the outlet of the inlet pipe. As the reaction time increases, the product accumulates, causing blockage in the gas pipeline, forcing the reaction to stop. This necessitates periodic disassembly and cleaning, severely impacting the continuous operation of the reactor and the stability of product quality. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a gas-liquid reactor for preparing lithium carbonate, wherein the gas inlet pipe is not blocked during the preparation of lithium carbonate and the utilization rate of carbon dioxide is high.

[0004] To achieve the objectives of this invention, the following technical solutions are provided.

[0005] A gas-liquid reaction vessel for preparing lithium carbonate, the reaction vessel comprising a vessel body, a vessel lid, and a vessel bottom; an outlet is located on the outer surface of the vessel bottom, and a valve is provided on the outlet to control the transfer of materials;

[0006] A motor is fixedly installed at the center of the outer surface of the vessel lid, and a sealing device is set between the motor and the outer surface of the vessel lid to prevent impurities from entering the reactor.

[0007] The motor drives the rotating shaft to rotate via a coupling. The rotating shaft extends into the reactor and one or more stirring blades are installed on the rotating shaft along its axial direction. During the rotation of the rotating shaft, it is ensured that the rotating shaft and stirring blades do not come into contact with the inner wall of the reactor.

[0008] A baffle is installed inside the reactor; the upper end of the baffle is fixed to the reactor lid, and the two sides of the baffle are fixed to the inner wall of the reactor body to prevent air leakage; the lower end of the baffle is spaced at a certain distance from the inner wall of the reactor bottom.

[0009] At least one liquid inlet pipe and at least one air inlet pipe are installed on the vessel lid, and an air venting valve is also installed on the vessel lid; the bottom end of the air inlet pipe is spaced at a set distance from the highest point of the liquid level in the reactor; the air venting valve is installed between the baffle and the inner wall of the vessel near the baffle.

[0010] Furthermore, only a venting valve is installed on the vessel lid between the baffle and the inner wall of the vessel near the baffle.

[0011] Furthermore, the inlet pipe and the vent valve are respectively installed on the lid on opposite sides of the motor; this ensures that the carbon dioxide gas has a long travel path in the reactor, so that it can fully react with the lithium hydroxide solution.

[0012] Furthermore, the lid of the vessel has an arc-shaped structure or a flat plate structure.

[0013] Furthermore, the bottom of the vessel has a conical structure or an outwardly convex arc-shaped structure to facilitate the transfer of solid materials.

[0014] Furthermore, the sealing device is a bearing sealing device, a mechanical sealing device, or a magnetohydrodynamic sealing device.

[0015] Furthermore, the baffle can be a flat plate structure, a corrugated plate structure, or a curved plate structure.

[0016] Furthermore, the vessel lid is also equipped with a pressure gauge, a cleaning ball, and a sight glass; the pressure gauge is used to monitor the pressure of the reactor; the cleaning ball is used to rinse the reactor; and the sight glass is installed on the vessel lid through the sight glass inlet to observe the reaction inside the reactor in real time.

[0017] Beneficial effects

[0018] This invention provides a gas-liquid reactor for preparing lithium carbonate. The reactor controls the inlet pipe to not submerge the surface of the lithium hydroxide solution within the reactor during operation, avoiding direct contact between the inlet pipe and the liquid phase, thus preventing gas pipeline blockage. Simultaneously, by installing a baffle in the gas-liquid reactor, the movement path of carbon dioxide in the lithium hydroxide solution is increased. This ensures that unreacted carbon dioxide gas must undergo further reaction with the lithium hydroxide solution before only a small portion escapes through the vent valve, improving the utilization rate of carbon dioxide. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the gas-liquid reaction vessel.

[0020] Figure 2 This is a schematic diagram of the baffle inside the gas-liquid reactor.

[0021] Among them, 1-vessel body, 2-vessel cover, 3-vessel bottom, 4-outlet, 5-valve, 6-motor, 7-mechanical seal device, 8-rotating shaft, 9-three-bladed oblique propeller, 10-liquid inlet pipe, 11-air inlet pipe, 12-venting valve, 13-pressure gauge, 14-cleaning ball, 15-sight glass, 16-baffle. Detailed Implementation

[0022] The present invention will be further described below with reference to specific embodiments and accompanying drawings.

[0023] Example 1

[0024] like Figures 1-2 As shown, a gas-liquid reactor for preparing lithium carbonate includes a reactor body 1, a reactor lid 2, and a reactor bottom 3; the reactor lid 2 has a flat plate structure; the reactor bottom 3 has an outwardly convex arc-shaped structure to facilitate the transfer of solid materials. An outlet 4 is located at the center of the reactor bottom 3, and the outlet 4 is welded to the outer surface of the reactor bottom 3. The outlet 4 is also equipped with a valve 5 to control the transfer of materials.

[0025] A motor 6 is fixedly installed at the center of the outer surface of the vessel lid 2. A mechanical seal device 7 is provided between the motor 6 and the outer surface of the vessel lid 2 to prevent impurities from entering the reactor.

[0026] The motor 6 drives the rotating shaft 8 to rotate through the coupling. The rotating shaft 8 extends into the reactor. Three-bladed oblique propellers 9 are fixedly installed at the middle and lower ends of the rotating shaft 8, respectively. During the rotation of the rotating shaft 8, the rotating shaft 8 and the three-bladed oblique propellers 9 are ensured not to contact the inner wall of the reactor.

[0027] A vertical baffle 16 is installed on one side of the reactor, near the inner wall of the reactor body 1. The baffle 16 is a flat plate structure. The upper end of the baffle 16 is welded to the reactor cover 2, and the two sides of the baffle 16 are welded to the inner circumference of the reactor body 1 to prevent air leakage. The lower end of the baffle 16 is close to the inner wall of the reactor bottom 3, but does not contact the inner wall of the reactor bottom 3.

[0028] A liquid inlet pipe 10 and a gas inlet pipe 11 are installed on the vessel lid 2. The vessel lid 2 is also equipped with a vent valve 12, a pressure gauge 13, a cleaning ball 14, and a sight glass 15. The liquid inlet pipe 10, pressure gauge 13, gas inlet pipe 11, and cleaning ball 14 are located on one side of the motor 6. The liquid inlet pipe 10 is used to add lithium hydroxide solution to the reactor; the gas inlet pipe 11 is used to introduce carbon dioxide gas into the reactor. The bottom end of the gas inlet pipe 11 is spaced a certain distance from the highest point of the liquid surface in the reactor. This distance ensures that when the reactor is working, the bottom end of the gas inlet pipe 11 still maintains a certain distance from the liquid surface in the reactor, so that the bottom end of the gas inlet pipe 11 does not submerge the liquid surface in the reactor, preventing lithium carbonate crystals from adhering to the bottom end of the gas inlet pipe 11, i.e., the outlet of the gas inlet pipe 11, during the reaction process. The cleaning ball 14 is used to rinse the reactor. The pressure gauge 13 is used to monitor the pressure of the reactor.

[0029] The vent valve 12 and the sight glass 15 are located on the other side of the motor 6. The vent valve 12 is installed between the baffle 16 and the inner wall of the vessel body 1 near the baffle 16. Only the vent valve 12 is located on the vessel cover 2 between the baffle 16 and the inner wall of the vessel body 1 on this side. The inlet pipe 11 and the vent valve 12 are respectively located on the vessel cover 2 on two opposite sides of the motor 6. The sight glass 15 is installed on the vessel cover 2 through the sight glass inlet to observe the reaction in the reactor in real time.

[0030] The gas-liquid reactor of this embodiment is applied to the process of preparing lithium carbonate from carbon dioxide and lithium hydroxide solution. Specifically, 25L of lithium hydroxide solution is added to the reactor through the liquid inlet pipe 10, and carbon dioxide is introduced into the reactor through the gas inlet pipe 11 at a flow rate of 15L / min. The motor 6 is turned on. When the rotating shaft 8 in the reactor drives the three-bladed impeller 9 to start rotating and stirring, the lithium hydroxide solution is thrown towards the inner wall of the reactor body 1 under centrifugal force, forming a low-pressure cavitation zone in the middle of the reactor body 1. Therefore, carbon dioxide gas can be drawn in. The drawn-in carbon dioxide gas fully mixes, contacts, and reacts with the lithium hydroxide solution. Figure 1 The arrowed lines simply illustrate the path of the carbon dioxide gas. The unreacted carbon dioxide gas passes through baffle 16 below the liquid surface, undergoes gas-liquid separation, and is discharged from vent valve 12. During the reaction, the pressure of the reactor is monitored by pressure gauge 13; the reaction is observed in real time through sight glass 15; the reaction ends when the pH of the reaction liquid in the reactor reaches 10. Using the gas-liquid reactor described in this embodiment, the reaction time is 102 minutes. This reactor can operate continuously without the risk of gas pipeline blockage, and the carbon dioxide utilization rate reaches 62%. After the reaction, valve 5 at outlet 4 is opened to transfer the material out of the reactor, and then the reactor is rinsed with cleaning ball 14.

[0031] Comparative Example 1

[0032] Unlike Example 1, the gas-liquid reactor provided in this comparative example does not have baffle 16; otherwise, it is the same as in Example 1. The gas-liquid reactor of this comparative example was applied to a process for preparing lithium carbonate from carbon dioxide and lithium hydroxide solution. The reaction conditions were the same as in Example 1, the reaction time was 220 min, and the carbon dioxide utilization rate was only 27%.

[0033] Comparative Example 2

[0034] Unlike Example 1, the gas-liquid reactor provided in this comparative example does not have a baffle 16, and the inlet pipe 11 extends below the surface of the lithium hydroxide solution. All other aspects are the same as in Example 1. When the gas-liquid reactor of this comparative example was applied to a process for preparing lithium carbonate from carbon dioxide and lithium hydroxide solution, under the same reaction conditions as in Example 1, the inlet pipe 11 became blocked after 51 minutes of reaction, forcing the reaction to stop and the inlet pipe to be cleaned.

[0035] By comparing Example 1, Comparative Example 1, and Comparative Example 2, it can be seen that by setting a baffle 16 in a conventional lithium carbonate preparation gas-liquid reactor and ensuring that the length of the inlet pipe 11 does not exceed the liquid surface in the reactor during operation, the problem of the inlet pipe 11 being easily blocked during the reaction process is solved, enabling continuous preparation and production of lithium carbonate, and also improving the utilization rate of carbon dioxide.

[0036] This invention includes, but is not limited to, the above embodiments. Any equivalent substitutions or partial improvements made under the spirit and principles of this invention shall be considered within the scope of protection of this invention.

Claims

1. A gas-liquid reaction vessel for preparing lithium carbonate, characterized in that: The reactor includes a vessel body (1), a vessel cover (2), and a vessel bottom (3); an outlet (4) is located on the outer surface of the vessel bottom (3), and a valve (5) is provided on the outlet (4); A motor (6) is fixedly installed on the outer surface of the lid (2), and a sealing device is provided between the motor (6) and the outer surface of the lid (2); The motor (6) drives the rotating shaft (8) to rotate through the coupling. The rotating shaft (8) extends into the reactor. One or more stirring blades are set on the rotating shaft (8) along its axial direction. A baffle (16) is installed inside the reactor; the upper end of the baffle (16) is fixed to the reactor lid (2), and the two sides of the baffle (16) are fixed to the inner wall of the reactor body (1); the lower end of the baffle (16) is spaced at a certain distance from the inner wall of the reactor bottom (3). At least one liquid inlet pipe (10) and at least one air inlet pipe (11) are provided on the lid (2). An air release valve (12) is also provided on the lid (2). The bottom end of the air inlet pipe (11) is spaced at a set distance from the highest point of the liquid level in the reactor. The air release valve (12) is installed between the baffle (16) and the inner wall of the reactor body (1) near the baffle (16). The lid (2) is also equipped with a pressure gauge (13), a cleaning ball (14) and a sight glass (15).

2. The gas-liquid reaction vessel for preparing lithium carbonate according to claim 1, characterized in that: Only a venting valve (12) is provided on the lid (2) between the baffle (16) and the inner wall of the vessel body (1) near the baffle (16).

3. The gas-liquid reaction vessel for preparing lithium carbonate according to claim 2, characterized in that: The air inlet pipe (11) and the air vent valve (12) are respectively installed on the lid (2) on opposite sides of the motor (6).

4. The gas-liquid reaction vessel for preparing lithium carbonate according to claim 1, characterized in that: The lid (2) is either an arc-shaped structure or a flat plate structure.

5. A gas-liquid reaction vessel for preparing lithium carbonate according to claim 1, characterized in that: The bottom of the vessel (3) is a conical structure or an outwardly convex arc-shaped structure.

6. The gas-liquid reaction vessel for preparing lithium carbonate according to claim 1, characterized in that: The sealing device is a bearing sealing device, a mechanical sealing device (7), or a magnetohydrodynamic sealing device.

7. A gas-liquid reaction vessel for preparing lithium carbonate according to claim 1, characterized in that: The baffle (16) is a flat plate structure, a wave plate structure or a curved plate structure.

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