A lithium battery electrode material filtering, washing and drying device

Abstract

The present invention provides a lithium battery electrode material filtering, washing and drying process, comprising a filtering, washing and drying machine, the filtering, washing and drying machine comprising a tank body and a heating and heat exchange system, a filtering and drying system, and a liquid inlet and liquid discharge system arranged on the tank body, the tank body having a feed port and a discharge port, and a compressed air inlet; the heating and heat exchange system comprising a stirring shaft and a stirring paddle, and a jacket arranged on the outer layer of the tank body; the filtering and drying system comprising a filter screen at the bottom of the tank body, a gas distribution plate, and a chassis; the liquid inlet and liquid discharge system comprising a material pipeline, and an air heating heat exchanger, a purified water heating heat exchanger, and a plurality of mother liquid tanks connected to the tank body through other pipelines; the device can realize the filtering, washing and drying process of lithium battery electrode materials such as iron phosphate, lithium carbonate, and manganese sulfate in a fully enclosed container, and the process reduces the investment in intermediate transportation links and equipment in different processes, improves production efficiency, reduces production cost, saves energy and protects the environment, and reduces land occupation and operating costs.

Description

Technical Field

[0001] The invention relates to the field of lithium battery electrode materials, in particular to a lithium battery electrode material filtering, washing and drying device. Background Art

[0002] With the rise of electric vehicles, the demand for lithium batteries has increased, and the demand for the production and recycling of lithium battery electrode materials has also increased greatly. The production process of lithium battery electrode raw materials such as iron phosphate, lithium carbonate and manganese sulfate is complicated. From the early synthesis to the later product separation and purification, it has to go through reaction, filtration, washing, drying and other processes. At present, the conventional production method in the industry is to filter and rinse the electrode materials after reaction synthesis, then pulp and wash them in the sedimentation tank, and then filter and rinse them again in the plate and frame. After repeated pulping, washing and filtering, they are spray dried or dried in a rotary kiln. Some processes use centrifuges instead of plate and frame filtration to repeat the above operations.

[0003] The above production process is cumbersome and complicated, so the applicant hopes to invent and design a lithium battery electrode material filtering, washing and drying equipment to achieve three-in-one filtering, washing and drying in the same equipment, so as to reduce the repeated transportation links in the middle, improve production efficiency, and the fully enclosed operation is safer and more environmentally friendly. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings and deficiencies of the prior art and to provide a lithium battery electrode material filtering, washing and drying device. The technical solution adopted by the present invention is as follows:

[0005] A lithium battery electrode material filtering, washing and drying device, comprising a tank body and a heating and heat exchange system, a filtering and drying system, and a liquid inlet and discharge system arranged on the tank body, wherein the tank body has a feed inlet and a discharge inlet, and a compressed air A inlet for introducing compressed air;

[0006] The heating and heat exchange system comprises a stirring shaft and a stirring paddle which are arranged in a tank body and are linked to a motor, and a jacket which is arranged on the outer layer of the tank body; the stirring shaft and the stirring paddle are arranged hollow, and the stirring shaft is provided with a stirring paddle steam inlet and a stirring paddle steam condensate outlet for passing fluid into and out of the stirring shaft and the stirring paddle, and the jacket is provided with a jacket steam inlet and a jacket steam condensate outlet;

[0007] The filtering and drying system comprises a filter screen arranged at the bottom of the tank body, a gas distribution plate arranged close to the bottom of the filter screen, and a chassis located at the bottom of the gas distribution plate; the gas distribution plate has an inlet for compressed air B, and exhaust ports are evenly distributed on the gas distribution plate, and a chassis steam inlet and a chassis condensed water outlet are arranged on the chassis;

[0008] The liquid inlet and discharge system includes a material pipeline connected to the feed port, and a compressed air heating heat exchanger, a purified water heating heat exchanger, a mother liquid tank A, a mother liquid tank B, and a mother liquid tank C connected to the tank body through other pipelines. The mother liquid tank A, the mother liquid tank B, and the mother liquid tank C are respectively provided with branch pipelines connected to the feed port and drainage pipelines for draining liquid.

[0009] The above-mentioned filtering, washing and drying device integrates the functions of filtering, washing and drying. The heating and heat exchange system is used to control the temperature of the tank body. The stirring paddle is hollow, which is convenient for further heating the material when the stirring paddle is stirring; the filtering and drying system cooperates with the compressed air introduced to filter the material, and the gas distribution plate and the chassis further control the ventilation and heating to improve the filtering and drying efficiency; the liquid inlet and discharge system is used to input materials and heat the gas and liquid. The mother liquor tank A, mother liquor tank B, and mother liquor tank C are used to collect the washing liquid in batches, which is convenient for targeted treatment or secondary utilization of the washing liquid.

[0010] Furthermore, the other pipelines include steam pipelines, compressed air pipelines, purified water pipelines, and vacuum system pipelines; the steam pipelines are used to introduce industrial steam into the agitator and the chassis; the compressed air pipeline is connected to the air heating heat exchanger, and its outlet end is connected to the compressed air A inlet and the compressed air B inlet arranged on the tank body; the purified water pipeline is connected to the purified water heating heat exchanger, and its outlet end is connected to the purified water inlet arranged on the tank body; the vacuum system pipeline is connected to the vacuum port on the tank body.

[0011] This device is implemented through the following steps:

[0012] S1: The material is introduced into the tank through the material pipeline;

[0013] S2: The compressed air pipeline is connected to the compressed air heating heat exchanger and the compressed air is introduced into the tank body through the compressed air inlet A to filter the material so that the material can be separated into solid and liquid through the filter screen; the mother liquid obtained by separation flows into the mother liquid tank A from the mother liquid port, and the mother liquid tank A is connected to the A drainage pump, and the A drainage pump outlet is connected to two branches, one of which is connected to the three-in-one feed port, and the other branch is used for drainage;

[0014] S3: The purified water pipeline is connected to the purified water heating heat exchanger, and its outlet is connected to the purified water inlet. After the first filter press is completed, purified water is introduced into the tank body, and the stirring paddle is started for pulping and cleaning;

[0015] S4: After the cleaning in step S is completed, secondary filter pressing is performed, and the washing liquid obtained by the secondary filter pressing is passed into the mother liquid tank B, and the mother liquid tank B is connected to the B drainage pump, and the outlet of the B drainage pump is connected to two branches, one of which is connected to the feed port, and the other branch is used for drainage;

[0016] S5: After the second filtration, purified water is introduced again to wash the material, and then the filtration is performed three times, and the washing liquid obtained is introduced into the mother liquor tank C, the mother liquor tank C is connected to a C drainage pump, and the C drainage pump outlet is connected to two branches, one of which is connected to the feed port, and the other branch is used for drainage;

[0017] S6: Dry the solid filter cake obtained after three filtrations. During the drying process, hot compressed air is introduced into the tank to heat the material. At the same time, the vacuum system and the stirring paddle are started. The stirring paddle slowly moves downward and rotates to loosen the material. The compressed air B inlet is opened and the pressure is controlled to make the material boil and dry. After drying, the material is stirred by the stirring paddle and discharged from the discharge port.

[0018] Preferably, the compressed air heat exchanger, purified water heating heat exchanger and jacket are all connected to the steam pipeline to adjust the washing temperature according to different materials.

[0019] Preferably, a microwave source is also provided on the tank body, and the microwave source is used to perform radiation heating on the tank body, and can be used to start microwave heating after the material is loosened during drying.

[0020] Preferably, the stirring shaft is driven by a motor to realize forward, reverse, lifting and lowering of the stirring paddle; the stirring paddle has an S-shaped cone structure, including 2-6 blades, a rotation speed of 0-20RPM, and industrial steam can be introduced into the stirring paddle and the blades through the stirring shaft. During the drying process, the blades are in direct contact with the material for heating. Multiple pairs of blades can be arranged as needed to increase the heat transfer area and improve the drying efficiency.

[0021] Preferably, in step S, the washing liquid in the mother liquor tank C is used for the first washing of the next batch of similar materials.

[0022] Preferably, the filtering area of ​​the filter is 0.05-10㎡, and the pore size of the filter is 5-50μm. Different filter screens can be selected according to the particle size of different electrode materials. A gas distribution plate is designed at the bottom of the filter screen. In the later stage of drying, compressed air blows up the material on the filter screen through the gas distribution plate, increasing the contact area between the material and the jacket, stirring paddle and microwave, thereby accelerating the drying efficiency.

[0023] Preferably, a heat-insulating layer is provided outside the jacket to further insulate the tank body.

[0024] The beneficial effects of the present invention are as follows: the present invention provides a device capable of realizing three-in-one filtering, washing and drying of electrode materials, and the device can realize the filtering, washing and drying process of lithium battery electrode materials such as iron phosphate, lithium carbonate and manganese sulfate in a fully enclosed container, and the process simplifies the existing production process of electrode materials, reduces the investment in intermediate transportation links and equipment in different processes, reduces the plant floor space, improves production efficiency and reduces production costs, saves energy and protects the environment, and reduces floor space and operating costs;

[0025] There are multiple heating methods, including hot compressed air heating, steam jacket heating, steam stirring paddle heating, and microwave heating, to improve heating efficiency; a gas distribution plate is designed at the bottom of the filter screen to adjust and control the compressed air pressure during the drying process, and to turn the material over during the stirring and drying process to increase the contact area between the material and the hot compressed air, tank wall, stirring paddle and microwave; multiple groups of mother liquid tanks are set up to realize the recycling of washing liquid, greatly reducing the amount of washing liquid used;

[0026] In addition, the washing liquid in this process can be temperature-controlled and adjusted according to different materials. The system has a high degree of automation and can use the program to set a variety of filtering and drying methods. Different washing and drying methods are used according to the characteristics of different lithium battery electrode materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying creative labor, other drawings obtained based on these drawings still belong to the scope of the present invention.

[0028] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0029] Figure 2 This is a schematic diagram of the structure of the stirring paddle in Example 1 of the present invention;

[0030] Figure 3 This is another schematic diagram of the stirring paddle structure of Example 1 of the present invention;

[0031] Figure 4 This is a schematic diagram of the screen structure of Example 1 of the present invention;

[0032] Figure 5 This is a schematic diagram of pipeline connection in Example 1 of the present invention;

[0033] In the figure, 1, filtering, washing and drying device; 2, compressed air heating heat exchanger; 3, purified water heating heat exchanger; 4, mother liquid A tank; 5, mother liquid B tank; 6, mother liquid C tank; 7, A drainage pump; 8, B drainage pump; 9, C drainage pump, 30, vent; 31, stirring paddle steam inlet; 32, stirring paddle steam condensate outlet; 33, stirring paddle motor; 34, purified water inlet; 35, compressed air A inlet; 36, vacuum port; 37, jacket steam inlet; 38, jacket condensate outlet; 39, compressed air B inlet; 40, feed port; 41, insulation layer; 42, jacket; 43, tank body; 44, stirring shaft; 45, stirring paddle; 46, filter screen; 47, gas distribution plate; 48, chassis steam inlet; 49, chassis condensate outlet; 50, mother liquid port; 51, chassis; 52, discharge port; 53, microwave source. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0035] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0036] The directions and positions mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", "inside", "outside", "top", "bottom", "side", etc., are only for reference to the directions or positions of the drawings. Therefore, the directions and positions used are for explaining and understanding the present invention, but not for limiting the scope of protection of the present invention.

[0037] Example 1

[0038] like Figure 1-5 As shown, a filtering, washing and drying process for lithium battery electrode materials includes a filtering, washing and drying machine, a tank body 43 of the filtering, washing and drying machine is provided with a jacket 42, a jacket steam inlet 37 and a jacket condensate outlet 38 are provided on the jacket 42, an insulating layer 41 is provided outside the jacket 42, a stirring shaft 44 is provided inside the filtering, washing and drying machine, the stirring shaft 44 is connected to a stirring paddle 45, a stirring paddle steam inlet 31 and a stirring paddle steam condensate outlet 32 ​​are provided on the stirring shaft 44, the stirring shaft 44 is driven by a stirring paddle motor 33, and the stirring paddle 45 can be rotated forward, reversed, lifted and lowered, the stirring paddle 45 is an S-shaped cone structure with 2-6 blades 45A and 45B, steam is passed through the stirring paddle 45, and the stirring paddle 45 is in direct contact with the material to improve the drying efficiency.

[0039] A filter screen 46 is provided at the bottom of the tank body 43, and a gas distribution plate 47 is provided at the bottom of the filter screen 46. There is a compressed air B inlet 39 on the gas distribution plate 47, and exhaust ports 47a are evenly distributed on the gas distribution plate 47. The gas distribution plate 47 is tightly attached to the bottom of the filter screen 46. During the drying process, hot compressed air enters from the compressed air B inlet 39 and is distributed by the gas distribution plate 47, and then blows the material on the filter screen 46 evenly from the exhaust port 47a to make the material boil; a bottom plate 51 is provided at the bottom of the gas distribution plate, and a bottom plate steam inlet 48 and a bottom plate condensed water outlet 49 are provided on the bottom plate 51.

[0040] The tank body is also provided with a purified water inlet 34 , a compressed air A inlet 35 , a vacuum port 36 , a feed port 40 , a mother liquid port 50 and a microwave source 53 .

[0041] The material pipeline 10 is connected to the feed port 40 of the three-in-one tank body 43, and the material is pumped into the feed port 40. The compressed air pipeline 12 is connected to the compressed air heating heat exchanger 2, and its outlet end is connected to the compressed air A inlet 35 and the compressed air B inlet 39. The vent 30 is closed, and the compressed air A inlet 35 is opened. The compressed air is filtered into the three-in-one tank body 43, and the material is separated from the solid by the filter screen 46. The mother liquid flows into the mother liquid A tank 4 from the mother liquid port 50. The bottom of the mother liquid A tank 4 is connected to the A drainage pump 7, and the outlet of the A drainage pump 7 is connected to two branches, one of which 15 is connected to the feed port 40 of the three-in-one tank body 43, and the other branch 16 is a drainage pipeline.

[0042] The purified water pipeline 13 is connected to the purified water heating heat exchanger 3, and its outlet end is connected to the purified water inlet 34 of the three-in-one tank body 43. After the filter press is completed, purified water is introduced into the three-in-one tank body 43, and the water is pulped and cleaned by the stirring paddle 45. After cleaning, the filter press is performed, and the washing liquid enters the mother liquid B tank 5. The washing liquid is introduced again to wash the material for the second time, and then the filter press is performed again, so that the secondary washing liquid enters the mother liquid C tank 6. The washing liquid in the mother liquid C tank 6 can be used for the first washing of the next batch of materials.

[0043] The mother liquid B tank 5 and the mother liquid C tank 6 are also designed with B drainage pump 8 and C drainage pump 9, and the outlets have two branches respectively, of which the B branch 17 and the C branch 19 are connected to the three-in-one feed port 40, and the other branches 18 and 20 are used for drainage.

[0044] The compressed air heating heat exchanger 2, the purified water heating heat exchanger 3, the jacket 42 of the three-in-one tank 43, the stirring paddle 45, and the bottom plate 51 are all connected with the steam pipeline 11. Purified water can achieve different washing temperatures according to different process requirements.

[0045] The washed qualified materials are directly dried in the three-in-one tank body 43: during the drying process, hot compressed air is introduced into the three-in-one tank body 43 to heat the material filter cake, and at the same time, the vacuum system 14 is turned on, and the stirring paddle 45 rotates and slowly scrapes the material loose. After the material is loosened, the microwave source 53 is turned on for heating, and the compressed air B inlet 39 is turned on to control the pressure to make the material boil and dry. After drying, the material is automatically discharged from the discharge port 52 through the stirring paddle 45; the above equipment and process can complete the filtering, washing and drying of lithium battery electrode materials in the filter washing and drying machine.

[0046] Application Example 1

[0047] The process in Example 1 is applied to the recovery of manganese sulfate from waste batteries using lithium electricity: compressed air pressure 0.2 MPa, temperature 120°C, purified water temperature 80°C, steam pressure 0.2, vacuum pressure -0.09 MPa, washing solid-liquid ratio 1:1, washing 3 times, conductivity less than 500 μs, initial water content of manganese sulfate after filtration pressure 15-25%, moisture 0.4% when drying time 120 min, moisture 0.1% when drying time 150 min.

[0048] Application Example 2

[0049] The process in Example 1 is applied to the treatment of lithium battery electrode material iron phosphate: compressed air pressure 0.3MPa, temperature 120°C, purified water temperature 25°C, steam pressure 0.4, vacuum pressure -0.08MPa, washing solid-liquid ratio 1:3, washing 4 times, conductivity less than 500μs, initial water content of iron phosphate after filter pressing 20-30%, drying time 120min, moisture 11%, drying time 180min, moisture 6%.

[0050] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A lithium battery electrode material filtering, washing and drying device, characterized in that: The filtering, washing and drying device comprises a tank body (43) and a heating and heat exchange system, a filtering and drying system, and a liquid inlet and discharge system arranged on the same tank body (43); The tank body (43) has a feed port (40), a discharge port (52), a vacuum port (36), a compressed air A inlet (35) for introducing compressed air, and a purified water inlet (34) for introducing purified water; The heating and heat exchange system comprises a stirring shaft (44) and a stirring paddle (45) arranged in a tank body (43), and a jacket (42) arranged on the outer layer of the tank body (43); the stirring shaft (44) and the stirring paddle (45) are hollow, and the stirring shaft (44) is provided with a stirring paddle steam inlet (31) and a stirring paddle steam condensate outlet (32); the jacket (42) is provided with a jacket steam inlet (37) and a jacket condensate outlet (38); The filtering and drying system comprises a filter screen (46) located at the bottom of the tank body (43), a gas distribution plate (47) at the bottom of the filter screen (46), and a bottom plate (51) located at the bottom of the gas distribution plate (47); the gas distribution plate (47) has a compressed air B inlet (39), and the gas distribution plate (47) is provided with exhaust ports (47a); the bottom plate (51) is provided with a bottom plate steam inlet (48) and a bottom plate condensed water outlet (49); The liquid inlet and discharge system comprises a material pipeline (10) connected to the feed port (40), and a compressed air heating heat exchanger (2), a purified water heating heat exchanger (3), a mother liquid A tank (4), a mother liquid B tank (5), and a mother liquid C tank (6) connected to the tank body (43) through other pipelines, wherein the mother liquid A tank (4), the mother liquid B tank (5), and the mother liquid C tank (6) are respectively connected to a discharge pump, and each of the discharge pumps is respectively connected to a branch pipeline connected to the feed port (40) and a discharge pipeline for discharging liquid; The other pipelines include a steam pipeline (11), a compressed air pipeline (12), a purified water pipeline (13), and a vacuum system (14) pipeline; The steam pipe (11) is used to introduce industrial steam into the stirring blade (45) and the bottom plate (51); The compressed air pipeline (12) is connected to the compressed air heating heat exchanger (2), and its outlet end is respectively connected to the compressed air A inlet (35) and the compressed air B inlet (39) arranged on the tank body (43); The purified water pipeline (13) is connected to the purified water heating heat exchanger (3), and its outlet end is connected to the purified water inlet (34) arranged on the tank body (43); The vacuum system pipeline is connected to the vacuum port (36) on the tank body (43); The compressed air heating heat exchanger (2), the purified water heating heat exchanger (3) and the jacket steam inlet (37) are all connected to the steam pipeline (11) to adjust the washing temperature according to different materials; A microwave source (53) is also provided on the tank body (43), and the microwave source (53) is used to perform radiation heating on the inside of the tank body (43); A heat-insulating layer (41) is disposed outside the jacket (42); The implementation steps of the filtering, washing and drying device are as follows: S1: The material is introduced into the tank (43) through the material pipeline (10); S2: The compressed air pipeline (12) is connected to the compressed air heating heat exchanger (2) and the compressed air is introduced into the tank body (43) through the compressed air A inlet (35) to filter the material, so that the material is separated into solid and liquid through the filter screen (46), wherein the mother liquid obtained by separation flows into the mother liquid A tank (4) from the mother liquid port (50); S3: The purified water pipeline (13) is connected to the purified water heating heat exchanger (3), and its outlet end is connected to the purified water inlet (34). After the first filter press is completed, purified water is introduced into the tank body (43), and the stirring paddle (45) is started for pulping and cleaning; S4: After the cleaning in step S3 is completed, a secondary filter press is performed, and the washing liquid obtained by the secondary filter press is passed into the mother liquid B tank (5); S5: After the second filter press, the material is washed with purified water again, and then the filter press is performed for the third time. The washing liquid obtained is passed into the mother liquor tank C (6) and used for the first washing of the next batch of similar materials; S6: Dry the solid filter cake obtained after the three filter presses. During the drying process, hot compressed air is introduced into the tank body (43) to heat the material. At the same time, the vacuum system (14) and the stirring paddle (45) are started. The stirring paddle (45) slowly moves downward and rotates to loosen the material. The compressed air B inlet (39) is opened and the pressure is controlled to make the material boil and dry. After drying, the material is stirred by the stirring paddle (45) and discharged from the discharge port (52).

2. A lithium battery electrode material filtering, washing and drying device according to claim 1, characterized in that: The stirring shaft (44) is driven by the motor (33) to achieve forward rotation, reverse rotation, lifting and lowering of the stirring paddle (45).

3. A lithium battery electrode material filtering, washing and drying device according to claim 2, characterized in that: The stirring paddle (45) has an S-shaped conical structure and includes 2 to 6 paddle blades.

4. A lithium battery electrode material filtering, washing and drying device according to claim 1, characterized in that: The filtering area of ​​the filter screen (46) is 0.05-10 m2, and the pore size of the filter screen is 5-50 μm.

Images