Device for preparing sodium ion layered oxide precursor

Abstract

The utility model discloses a device for preparing a sodium ion layered oxide precursor. The device comprises a sodium ion layered oxide precursor system consisting of a sulfate tank, an alkali liquor tank, an ammonia water tank, a reaction kettle, a product filter pressing tank and a water storage tank, the wastewater treatment tank is used for evaporating ammonia gas and crystallizing sulfate, the upper end of the wastewater treatment tank is connected with the product filter pressing tank through a pipeline, the top end of the wastewater treatment tank is connected with the top end of the ammonia gas adsorption tower through a pipeline, and the bottom end of the ammonia gas adsorption tower is connected with the ammonia water tank through a pipeline. By controlling the flow rate of the wastewater and the temperature and pressure of the wastewater treatment tank, ammonia evaporation and sulfate crystallization are realized at the same time, the wastewater treatment process is simplified, the ammonia evaporation rate and the sulfate crystallization efficiency are improved, and the wastewater treatment cost is reduced; recycled ammonia water is directly put into production, so that the utilization rate of raw materials is increased; the ammonia gas adsorption tower is alternately provided with the spraying devices and the filler layers, so that the contact time of ammonia gas and water is prolonged, and the dissolution rate and the recovery efficiency of the ammonia gas are improved.

Description

Technical Field

[0001] The utility model relates to a preparation device for oxides, in particular to a device for preparing sodium-ion layered oxide precursors. Background Art

[0002] Sodium-ion layered oxides are similar to lithium-ion layered oxides and have advantages such as relatively high specific capacity, simple preparation, high tap density, and adjustable voltage range, and thus have attracted much attention in the preparation of batteries by replacing lithium-ion cathode materials. Their synthesis methods are still being explored. In the synthesis of sodium-ion layered oxides by the co-precipitation method, alkalis and sulfates are used as raw materials. After the raw materials are dissolved and mixed for reaction, ammonia water is added during which ammonium ions are used for complexation to form a turbid solution of the target product. By controlling the pH value, reaction temperature, stirring speed, reaction rate, reaction time, and the washing process, sodium-ion layered oxide precursor products with different morphologies and particle size distributions are obtained after pressure filtration. There is ammonia water and sulfate in the wastewater after the final pressure filtration in this method. Currently, ammonia removal or sulfur removal is usually carried out separately in the process. Due to the large amount of wastewater generated, separate treatment is time-consuming and laborious, and the recovered raw materials need to be transferred and stored and cannot be directly put into production, causing a huge economic burden to enterprises. Summary of the Utility Model

[0003] Purpose of the utility model: The purpose of the utility model is to simplify the wastewater treatment process for preparing sodium-ion layered oxide precursors by the co-precipitation method and directly recycle the recovered ammonia gas into production, and to provide a device for preparing sodium-ion layered oxide precursors.

[0004] Technical solution: The device for preparing sodium-ion layered oxide precursors described in the utility model includes a sodium-ion layered oxide precursor system composed of a sulfate tank, an alkali solution tank, an ammonia water tank, a reaction kettle, a product pressure filtration tank, and a water storage tank; it also includes a wastewater treatment tank for evaporating ammonia gas and crystallizing sulfates. The upper end of the wastewater treatment tank is connected to the product pressure filtration tank through a pipeline, the top end of the wastewater treatment tank is connected to the top end of an ammonia gas adsorption tower through a pipeline, and the bottom end of the ammonia gas adsorption tower is connected to the ammonia water tank through a pipeline.

[0005] Further, a flow controller for controlling the inflow rate of wastewater, a pressure regulating device for adjusting the pressure in the tank, and a heating device for adjusting the temperature in the tank are provided on the wastewater treatment tank to improve the wastewater treatment efficiency.

[0006] Further, a spraying device for dissolving ammonia gas and a packing layer for increasing the contact area between ammonia gas and water are provided at the top end of the ammonia gas adsorption tower. The material of the packing layer is ceramic, metal, or plastic, preferably polypropylene; the spraying device and the packing layer are arranged alternately to increase the contact time between ammonia water and water and improve the dissolution efficiency of ammonia water.

[0007] Further, the spraying device is connected to the water storage tank.

[0008] Furthermore, a wastewater storage tank for temporary storage is provided between the product pressure filtration tank and the wastewater treatment tank.

[0009] Furthermore, demagnetizers for removing magnetic substances in the raw materials are provided on the pipelines connecting the sulfate tank, the lye tank, and the ammonia water tank to the reaction kettle.

[0010] Beneficial effects: Compared with the prior art, the utility model has the following advantages: 1. When the wastewater treatment tank is heated to about 150 °C, ammonia evaporation and sulfate crystallization are simultaneously achieved, simplifying the wastewater treatment process and reducing the wastewater treatment cost; 2. By controlling the flow rate of the wastewater and the temperature and pressure of the wastewater treatment tank, the ammonia evaporation rate and the sulfate crystallization efficiency are improved; 3. The recovered ammonia water is directly put into production, improving the utilization rate of raw materials; 4. The ammonia adsorption tower is alternately provided with a spraying device and a packing layer, increasing the contact time between ammonia and water, and improving the ammonia dissolution rate and recovery efficiency; 5. The device has a simple structure, is easy to operate, and is easy to promote. Description of the Drawings

[0011] Figure 1 It is a schematic structural diagram of the utility model. Detailed Embodiments

[0012] The technical solution of the utility model will be further described below with reference to the drawings.

[0013] As Figure 1 shown, a device for preparing sodium ion layered oxide precursor includes a sulfate tank 1, a lye tank 2, and an ammonia water tank 3. The sulfate tank 1, the lye tank 2, and the ammonia water tank 3 are connected to the top of the reaction kettle 4 through pipelines, and demagnetizers 12, 22, and 32 are respectively arranged on the pipelines; the bottom end of the reaction kettle 4 is sequentially connected to a product pressure filtration tank 5, a wastewater storage tank 6, a wastewater treatment tank 7, and an ammonia adsorption tower 9 through pipelines. A water storage tank 8 for providing pure water is respectively connected to the tops of the product pressure filtration tank 5 and the ammonia adsorption tower 9; the top end of the ammonia adsorption tower 9 is alternately provided with a spraying device 91 for dissolving ammonia and a packing layer 94 for increasing the contact area between ammonia and water. The bottom end of the ammonia adsorption tower 9 is connected to the ammonia water tank 3 through a pipeline, and the material of the packing layer 94 is polypropylene. A flow controller for controlling the inflow rate of wastewater, a pressure regulating device for adjusting the pressure in the tank, and a heating device for adjusting the temperature in the tank are provided on the wastewater treatment tank 7. A compressed air inlet 52 is provided at the top end of the product pressure filtration tank 5.

[0014] When the equipment is running, sulfate in the sulfate tank 1 is pumped through the sulfate pump 11, passes through the demagnetizer 12 to remove magnetic impurities, and then enters the reaction kettle 4 through the sulfate liquid inlet 41. Alkali liquid in the alkali liquid tank 2 is pumped through the alkali pump 21, passes through the demagnetizer 22 to remove magnetic impurities, and then enters the reaction kettle 4 through the alkali liquid inlet 42. Ammonia water in the ammonia water tank 3 is pumped through the ammonia water pump 31, passes through the demagnetizer 32 to remove magnetic impurities, and then enters the reaction kettle 4 through the ammonia water inlet 43. All raw materials are fully stirred and mixed by the stirrer, and the complexation of ammonium ions is utilized to generate a turbid liquid of the target product. The turbid liquid is pumped into the product pressure filter tank 5 through the turbid liquid inlet 53 by the turbid liquid pump 41. Compressed air is introduced into the tank through the compressed air inlet 52 to pressurize and filter the turbid liquid. Then, pure water in the water storage tank 8 is pumped into the pressure filter tank 5 through the first pure water pump 81 through the pure water inlet 53 to wash the target precursor. The wastewater generated by the washing is collected from the bottom of the pressure filter tank 5 and temporarily stored in the wastewater storage tank 6. The temperature in the wastewater treatment tank 7 is controlled at about 150 °C, the pressure in the wastewater treatment tank 7 is adjusted, and the rate of wastewater flowing into the wastewater treatment tank 7 is controlled by the wastewater pump 61 to evaporate ammonia in the wastewater and accelerate the crystallization of sulfate in the waste liquid. The evaporated ammonia is transported to the ammonia gas inlet 92 at the top of the ammonia gas adsorption tower 9 through the ammonia gas outlet 71 at the top of the wastewater treatment tank 7. Pure water in the water storage tank 8 is pumped into the spraying device 91 by the second pure water pump 82. The ammonia gas flows through the spraying device 91 and the packing layer 94 below the ammonia gas inlet 92 and is completely dissolved in water. The concentrated ammonia water flows through the ammonia water outlet 93 at the bottom of the ammonia gas adsorption tower 9 and is pumped into the ammonia water tank 3 by the second ammonia water pump 33 to complete the recycling and reuse of the wastewater.

Claims

1. A device for preparing a sodium ion layered oxide precursor, comprising a sodium ion layered oxide precursor system consisting of a sulfate tank (1), an alkali liquid tank (2), an ammonia water tank (3), a reaction kettle (4), a product filter press tank (5) and a water storage tank (8); characterized in that: It also includes a wastewater treatment tank (7) for evaporating ammonia and crystallizing sulfate, wherein the upper end of the wastewater treatment tank (7) is connected to the product filter press tank (5) via a pipeline, the top end of the wastewater treatment tank (7) is connected to the top end of an ammonia adsorption tower (9) via a pipeline, and the bottom end of the ammonia adsorption tower (9) is connected to an ammonia water tank (3) via a pipeline.

2. The device for preparing a sodium ion layered oxide precursor according to claim 1, characterized in that: The wastewater treatment tank (7) is provided with a flow controller for controlling the inflow rate of wastewater, a pressure regulating device for adjusting the pressure in the tank, and a heating device for adjusting the temperature in the tank.

3. The device for preparing a sodium ion layered oxide precursor according to claim 1, characterized in that: The top of the ammonia adsorption tower (9) is provided with a spray device (91) for dissolving ammonia and a packing layer (94) for increasing the contact area between ammonia and water.

4. The device for preparing a sodium ion layered oxide precursor according to claim 3, characterized in that: The spraying devices (91) and the filling layers (94) are arranged alternately.

5. The device for preparing a sodium ion layered oxide precursor according to claim 3 or 4, characterized in that: The material of the filler layer (94) is ceramic, metal or plastic.

6. The device for preparing a sodium ion layered oxide precursor according to claim 5, characterized in that: The material of the packing layer (94) is polypropylene.

7. The device for preparing a sodium ion layered oxide precursor according to claim 3, characterized in that: The spray device (91) is connected to the water storage tank (8).

8. The device for preparing a sodium ion layered oxide precursor according to claim 1, characterized in that: A wastewater storage tank (6) for temporary storage is provided between the product filter press tank (5) and the wastewater treatment tank (7).

9. The device for preparing a sodium ion layered oxide precursor according to claim 1, characterized in that: The pipelines connecting the sulfate tank (1), the alkali liquid tank (2) and the ammonia water tank (3) with the reaction kettle (4) are provided with a demagnetizer for removing magnetic substances in the raw materials.

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