Intermittent negative pressure lithium carbonate reaction apparatus

Abstract

The utility model discloses an intermittent negative pressure lithium carbonate reaction device, including the reaction kettle of sealed arrangement, the reaction kettle is from inside to outside and is equipped with reaction cavity, heat preservation layer in proper order, the reaction kettle bottom is provided with the unloading valve of reaction cavity intercommunication, still be equipped with high lithium solution liquid inlet pipe, sodium carbonate solution feed pipe on the reaction kettle lateral wall for feeding to the reaction cavity, still include negative pressure spare, the negative pressure spare sets up the lateral wall of reaction kettle for intermittent extraction reaction cavity in the reaction process water vapor, and when negative pressure spare intermittent extraction reaction cavity in water vapor reaches the stop negative pressure of preset value, through the negative pressure spare extraction reaction cavity in water vapor, improve reaction solution concentration, accelerate the reaction rate, and through the negative pressure spare intermittent extraction liquid in the lithium deposition process also reduces the risk that one -time extraction water vapor will take out Li+ in the solution.

Description

Technical Field

[0001] This utility model relates to a lithium carbonate reaction device, and more particularly to an intermittent negative pressure lithium carbonate reaction device. Background Technology

[0002] In the new energy field, lithium carbonate is a major upstream raw material. Lithium carbonate production is divided into brine method and mining method depending on the raw materials. Regardless of whether it is the brine method or the mining method, the basic steps of the process and equipment for producing lithium carbonate products (lithium precipitation section) are the same. The steps are as follows: high lithium solution and sodium carbonate solution react in a heated reaction stirring tank. After the reaction slurry is matured and thickened, it is sent downstream for multi-stage centrifugal filtration, re-slurry removal of impurities, and then sent for drying and packaging.

[0003] Patent CN210752651U discloses a continuous-feed, continuous-discharge lithium carbonate reactor, enabling continuous production. Through a raw material annular distributor, the reaction flow field distribution is good, and the material dispersion effect is excellent. However, according to the lithium carbonate reactor lithium precipitation method described, the lithium content of the precipitation mother liquor will not be lower than that of the traditional reactor process, and it is impossible to precisely control the amount of water used for subsequent washing. Furthermore, this device suffers from drawbacks such as low primary lithium precipitation efficiency, low production efficiency, and long cycle time.

[0004] In existing technologies, to improve the efficiency of primary lithium precipitation, the lithium content of the high-lithium solution and the sodium carbonate concentration can be increased. However, both methods result in impurities being trapped during the lithium carbonate crystallization process, leading to low product purity and increased difficulty and dosage in subsequent water washing. To address these technical problems, this invention proposes an intermittent negative pressure lithium carbonate reaction device. Summary of the Invention

[0005] To address the technical problems existing in the background art, this utility model proposes an intermittent negative pressure lithium carbonate reaction device, including a sealed reaction vessel. The reaction vessel is provided with a reaction chamber and a heat insulation layer from the inside to the outside. A discharge valve communicating with the reaction chamber is provided at the bottom of the reaction vessel. A high-lithium solution inlet pipe and a sodium carbonate solution inlet pipe are also provided on the side wall of the reaction vessel for feeding into the reaction chamber. It also includes a negative pressure component, which is provided on the side wall of the reaction vessel to intermittently extract water vapor in the reaction chamber during the reaction process; and the negative pressure is stopped when the intermittent extraction of water vapor in the reaction chamber by the negative pressure component reaches a preset value.

[0006] Preferably, the negative pressure component includes a steam condenser pipe and a heat exchange condenser. One end of the steam condenser pipe extends into the reaction chamber and the other end is connected to the heat exchange condenser. A negative pressure machine is also connected to the heat exchange condenser. A steam on / off valve is also provided on the steam condenser pipe.

[0007] Preferably, the heat exchange condenser is vertically arranged, and the negative pressure machine is connected to the top of the heat exchange condenser through a negative pressure pipe, and a negative pressure control valve is provided on the negative pressure pipe.

[0008] Preferably, the heat exchange condenser is connected to a condensate tank at the bottom, the condensate tank is equipped with a level gauge, and the condensate tank is equipped with a drain valve at the bottom.

[0009] Preferably, the reaction chamber is further provided with a high-pressure spray plate, the high-pressure spray plate is provided with inclined water spray holes, and the high-pressure spray plate is connected to a cleaning water pipe.

[0010] Preferably, the reactor also includes a stirring element, which includes a drive motor and a stirring paddle. The drive motor is mounted on the reactor and its drive end extends into the reaction chamber and is connected to the stirring paddle.

[0011] Preferably, the top of the reactor is also equipped with a pressure gauge, a thermometer, and a level gauge.

[0012] Preferably, a molecular sieve membrane is provided at one end of the steam condenser tube located inside the reaction chamber.

[0013] Preferably, the reactor is further provided with a heat transfer oil inlet and a heat transfer oil outlet to adjust the temperature of the insulation layer; the top of the reactor is also provided with an observation window to observe the reaction state inside the reaction chamber.

[0014] Preferably, the total volume of the high-lithium solution and sodium carbonate solution added to the reaction chamber does not exceed 80% of the reaction chamber volume, and the volume of the negative pressure extraction steam condensation is 1 / 5 of the total volume of the reaction liquid.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] By using a negative pressure device to extract water vapor from the reaction chamber, the concentration of the reaction solution is increased, and the reaction rate is accelerated. Furthermore, the intermittent extraction of the solution during the lithium precipitation process using the negative pressure device also reduces the risk of Li+ being carried out of the solution by a single extraction of water vapor. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is a schematic diagram of the high-pressure spray disc of this utility model. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar symbols denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] like Figures 1-2 An intermittent negative pressure lithium carbonate reaction device is shown, comprising a sealed reaction vessel 1. The reaction vessel 1 is provided with a reaction chamber and an insulation layer from the inside to the outside. A discharge pipe 16 communicating with the reaction chamber is provided at the bottom of the reaction vessel 1. A discharge valve 17 is provided on the discharge pipe 16. A high-lithium solution inlet pipe 3 and a sodium carbonate solution inlet pipe 2 are also provided on the side wall of the reaction vessel 1 for feeding into the reaction chamber. Both the high-lithium solution inlet pipe 3 and the sodium carbonate solution inlet pipe 2 are provided with inlet valves. The device is characterized by including a negative pressure component, which is located above the side wall of the reaction vessel 1 and is used to intermittently extract water vapor in the reaction chamber during the reaction process. The negative pressure is stopped when the volume of water vapor condensed in the reaction chamber by the negative pressure component reaches 1 / 5 of the total volume of the reaction liquid.

[0021] First, open the liquid inlet valve and feed the solution into the reaction chamber through the high-lithium solution inlet pipe 3 and the sodium carbonate solution inlet pipe 2 until the solution reaches 80% of the total volume of the reaction chamber. Then, close the liquid inlet valve and use the negative pressure device to extract water vapor from the reaction chamber to increase the concentration of the reaction solution and accelerate the reaction rate. The negative pressure device intermittently extracts water vapor until the volume of water vapor condensation reaches 1 / 5 of the total volume of the reaction solution, at which point the negative pressure is stopped. This increases the reaction rate and also reduces the risk of extracting Li+ from the solution.

[0022] In a further embodiment, the negative pressure component includes a steam condenser pipe 9 and a heat exchange condenser 11. One end of the steam condenser pipe 9 extends into the reaction chamber and the other end is connected to the middle of the heat exchange condenser 11. A negative pressure machine 12 is also connected to the heat exchange condenser 11. A steam on / off valve is also provided on the steam condenser pipe 9.

[0023] During intermittent negative pressure, the negative pressure machine is turned on to draw water vapor into the heat exchange condenser 11 through the steam condenser pipe 9, and the high-temperature water vapor is converted into condensate and collected through the heat exchange condenser. Once the collected water reaches the preset value, the steam on / off valve on the steam condenser pipe 9 can be closed to prevent local water vapor from remaining in the steam condenser pipe 9.

[0024] In a further embodiment, the heat exchange condenser 11 is vertically arranged, the negative pressure machine 12 is connected to the top of the heat exchange condenser 11 through a negative pressure pipe, and a negative pressure control valve 13 is provided on the negative pressure pipe;

[0025] By vertically setting the heat exchange condenser 11, the negative pressure machine is prevented from drawing condensate into its interior; at the same time, it can also ensure that the condensed liquid water can flow out of the condenser smoothly and be collected due to gravity; finally, by setting a negative pressure control valve 13 on the negative pressure pipeline, water vapor can be extracted intermittently.

[0026] In a further embodiment, the heat exchange condenser 11 is connected to a condensate tank 14 at its bottom, the condensate tank 14 is equipped with a level gauge, and the bottom of the condensate tank 14 is equipped with a drain valve 15.

[0027] The condensate is collected by the condensate tank 14 and the volume of water vapor extracted is detected by the level gauge. The level gauge can accurately determine whether the water vapor in the extraction reaction chamber has reached the preset value. After extraction, the condensate can be used to rinse the reaction chamber by opening the drain valve 15, thus realizing the recycling of water flow.

[0028] In a further embodiment, a high-pressure spray plate 6 is provided inside the reaction chamber, and an inclined water spray hole 62 is provided on the high-pressure spray plate 6. A cleaning water pipe 10 is provided on the side wall of the reaction vessel 1. The cleaning water pipe 10 extends into the reaction chamber and is connected to the high-pressure spray plate 6. The end of the cleaning water pipe 10 away from the reaction vessel is connected to a water tank / condensate tank 14 through a water inlet valve.

[0029] After the reaction is complete, the cleaning pipeline 10 is opened to rinse the inner wall of the reaction chamber through the high-pressure spray plate, effectively removing residues such as lithium carbonate precipitate and sodium chloride crystals from the inner wall of the vessel; the cleaning of the inner wall of the reaction chamber is better achieved by setting inclined water spray holes, ensuring the rinsing effect.

[0030] In a further embodiment, a stirring element 8 is also included. The stirring element 8 includes a drive motor 7 and a stirring paddle. The drive motor 7 is mounted on the reactor 1 and its drive end extends into the reaction chamber and is connected to the stirring paddle. That is, during the lithium precipitation process, the stirring paddle can be rotated to accelerate the full mixing of the two reaction liquids and improve the reaction efficiency. At the same time, during the cleaning process, the stirring paddle can also be used to stir the water in the reaction chamber, which is convenient for cleaning the inner wall of the reactor and the residue on the stirring rod.

[0031] In a further embodiment, the top of the reactor 1 is also equipped with a pressure gauge 18, a thermometer 19, and a level gauge 20;

[0032] The pressure gauge 18 facilitates the control of the pressure inside the reaction chamber at 0.04MPa-0.08MPa, which ensures negative pressure to improve reaction efficiency while avoiding excessive negative pressure that could draw out Li+. The thermometer 19 facilitates the control of the reaction temperature at 82-92℃, ensuring that the reaction is under optimal conditions. The liquid level gauge 20 also ensures the control of the liquid volume inside the reaction chamber.

[0033] In a further embodiment, a molecular sieve membrane is provided at one end of the vapor condenser 9 located inside the reaction chamber, which further reduces the possibility that the vapor condenser 9 will extract Li+ from the reaction solution.

[0034] In a further embodiment, a heat transfer oil outlet 5 is provided above the reactor 1, and a heat transfer oil inlet 21 is provided at the bottom of the reactor 1; both the heat transfer oil inlet 21 and the heat transfer oil outlet 5 are connected to the insulation layer; an observation window is also provided at the top of the reactor 1 for observing the reaction state inside the reaction chamber;

[0035] That is, by guiding oil into the insulation layer, the required reaction temperature is provided to the reaction chamber located inside the insulation layer, thereby increasing the reaction rate; by setting an observation window, the reaction state inside the reaction chamber can be better ensured, and the lithium deposition effect can be better controlled.

[0036] In a further embodiment, the total volume of the added high-lithium solution and sodium carbonate solution does not exceed 80% of the reaction chamber, and the preset value of the negative pressure extraction steam condensation volume is 1 / 5 of the total volume of the reaction liquid; this further avoids reducing the possibility of Li+ being extracted when extracting water vapor.

[0037] In a further embodiment, the steam condenser 9 extends into the reaction chamber with one end facing upwards and away from the reaction solution.

[0038] In a further embodiment, the reactor 1 is also provided with a spare port and a vent port that are connected to the insulation layer.

[0039] The working principle of this utility model is as follows: The reaction solution is injected into the reaction chamber by opening the inlet valves of the high-lithium solution inlet pipe 3 and the sodium carbonate solution inlet pipe 2 until the total volume of the injected reaction solution reaches 60%-80% of the volume inside the reaction chamber; the inlet valves are closed, and the reaction temperature is controlled at 82-92℃; the drive motor is turned on to rotate the stirring paddle, and after lithium precipitation for 20-30 minutes, the negative pressure control valve 13 and the steam on / off valve are opened every 10-15 minutes to extract water vapor from the reaction chamber until the volume of condensate in the condensate tank is detected to be 1 / 5 of the total volume of the reaction solution, at which point the negative pressure control valve 13 and the steam on / off valve are simultaneously closed; after lithium precipitation is completed, the discharge valve 17 is opened to guide the reacted slurry from the bottom of the reactor into the slurry storage tank, which is then sent to centrifugal separation or plate and frame filtration to obtain a wet lithium carbonate filter cake; after the lithium precipitation reaction in the reactor is repeated multiple times, the reaction chamber is rinsed by the high-pressure spray plate 6, and the cleaning solution is discharged through the discharge valve.

[0040] It should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0043] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0044] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An intermittent negative pressure lithium carbonate reaction device, comprising a sealed reaction vessel (1), wherein the reaction vessel (1) is provided with a reaction chamber and a heat insulation layer from the inside to the outside, and a discharge valve (17) communicating with the reaction chamber is provided at the bottom of the reaction vessel (1), and a high-lithium solution inlet pipe (3) and a sodium carbonate solution inlet pipe (2) are also provided on the side wall of the reaction vessel (1) for feeding into the reaction chamber, characterized in that, It also includes a negative pressure component, which is installed on the side wall of the reactor (1) to intermittently extract water vapor from the reaction chamber during the reaction process; Furthermore, the negative pressure will stop when the volume of water vapor condensed in the reaction chamber reaches the preset value through intermittent extraction by the negative pressure component.

2. The intermittent negative pressure lithium carbonate reactor according to claim 1, characterized in that, The negative pressure component includes a steam condenser pipe (9) and a heat exchange condenser (11). One end of the steam condenser pipe (9) extends into the reaction chamber and the other end is connected to the heat exchange condenser (11). A negative pressure machine (12) is also connected to the heat exchange condenser (11). A steam on / off valve is also provided on the steam condenser pipe (9).

3. The intermittent negative pressure lithium carbonate reactor according to claim 2, characterized in that, The heat exchange condenser (11) is set vertically, and the negative pressure machine (12) is connected to the top of the heat exchange condenser (11) through a negative pressure pipe. A negative pressure control valve (13) is provided on the negative pressure pipe.

4. The intermittent negative pressure lithium carbonate reactor according to claim 2, characterized in that, The heat exchange condenser (11) is connected to a condensate tank (14) at the bottom. The condensate tank (14) is equipped with a level gauge and a drain valve (15) at the bottom.

5. The intermittent negative pressure lithium carbonate reactor according to claim 2, characterized in that, The reaction chamber is also equipped with a high-pressure spray plate (6), which has inclined water spray holes (62) and is connected to a cleaning water pipe (10).

6. The intermittent negative pressure lithium carbonate reactor according to claim 2, characterized in that, It also includes a stirring component (8), which includes a drive motor (7) and a stirring paddle. The drive motor (7) is mounted on the reactor (1) and its drive end extends into the reaction chamber and is connected to the stirring paddle.

7. The intermittent negative pressure lithium carbonate reactor according to claim 2, characterized in that, The top of the reactor (1) is also equipped with a pressure gauge (18), a thermometer (19), and a level gauge (20).

8. The intermittent negative pressure lithium carbonate reactor according to claim 2, characterized in that, The steam condenser (9) is located inside the reaction chamber and has a molecular sieve membrane at one end.

9. The intermittent negative pressure lithium carbonate reactor according to any one of claims 1-8, characterized in that, The reactor (1) is also provided with a heat transfer oil inlet (21) and a heat transfer oil outlet (5) to adjust the temperature of the insulation layer; the top of the reactor (1) is also provided with an observation window to observe the reaction state inside the reaction chamber.

10. The intermittent negative pressure lithium carbonate reactor according to any one of claims 1-8, characterized in that, The total volume of the high-lithium solution and sodium carbonate solution added to the reaction chamber shall not exceed 80% of the reaction chamber volume, and the preset value of the negative pressure extraction steam condensation volume is 1 / 5 of the total reaction liquid volume.

Images