Cathode material ceramic powder flow regeneration device

Abstract

The utility model relates to a positive electrode material ceramic powder flow regeneration device which is characterized in that at least one high-temperature section furnace shell is sequentially stacked at an outlet at the bottom of a preheating section furnace shell, a cooling auger is arranged at an outlet of the bottommost high-temperature section furnace shell, a powder flow heat exchanger is arranged in the preheating section furnace shell, and a heating module is arranged in each high-temperature section furnace shell; a heat exchange medium outlet of the cooling auger is connected with a heat exchange medium inlet of the powder flow heat exchanger through a pipeline, and a heat exchange medium outlet of the powder flow heat exchanger is connected with a heat exchange medium inlet of the cooling auger through a heat circulating pump. The device has the beneficial effects that the high-temperature section of the structure adopts modular design, stacking can be carried out in the height direction according to the design capacity of a production line, capacity expansion is realized, equipment model selection and arrangement modes are flexible, the occupied area is small, materials flow in a dense phase in the furnace, the utilization rate of the space in the furnace is high, and the device meets the requirement of continuous regeneration of the lithium battery positive electrode material.

Description

Technical Field

[0001] The utility model relates to the technical field of positive electrode material regeneration, in particular to a positive electrode material ceramic powder flow regeneration device. Background Art

[0002] With the development of new energy technologies, power batteries and energy storage batteries have begun to be retired in large quantities. Retired batteries are rich in heavy metals such as mercury, cadmium, nickel, manganese, chromium, zinc, and acid, alkali and other electrolytes. The traditional extensive treatment methods such as deep burial and storage in abandoned mines pose environmental risks such as soil and groundwater pollution. It also causes a large waste of resources and is an unsustainable treatment method.

[0003] The recycling and reuse of used batteries can achieve the dual goals of reducing pollutants and harmlessly treating final emissions, which is of great significance to environmental protection. At the same time, recycling and extracting precious metals, electrolytes and other substances from used batteries can maximize the goal of reusing limited resources, realize the internal circulation of resources in the industry, create huge social value and achieve the goal of sustainable development.

[0004] There are currently two common methods for battery recycling and reuse in the market. One is element wet recycling, and the other is regeneration and repair of positive and negative electrode materials. The regeneration and repair technical route requires high-temperature carbonization of the positive electrode material to remove the PVDF (binder) added during the preparation of the battery pole piece, so as to improve the processing performance of the material after repair. When the rotary kiln and roller kiln commonly used in the market are used to produce recycled lithium battery positive electrode materials, the materials in the rotary kiln roll in the equipment, which requires an additional drive device and increases energy consumption, while the materials in the roller kiln are static, which is not conducive to uniform heat transfer. In addition, when using rotary kilns and roller kilns to produce recycled lithium battery positive electrode materials, there are still problems such as poor corrosion resistance, excessive magnetic foreign matter, uneven heating, and large equipment footprint. There is an urgent need for a device that can eliminate magnetic foreign matter, is corrosion-resistant, high-temperature resistant, has uniform heat energy distribution, and occupies a small area to solve this problem. Utility Model Content

[0005] The technical problem to be solved by the utility model is to provide a positive electrode material ceramic powder flow regeneration device to overcome the deficiencies in the above-mentioned prior art.

[0006] The technical solution of the utility model to solve the above-mentioned technical problems is as follows: a positive electrode material ceramic powder flow regeneration device, comprising: a preheating section furnace shell, an upper end cover is arranged at the top inlet of the preheating section furnace shell, at least one high-temperature section furnace shell is stacked in sequence at the bottom outlet of the preheating section furnace shell, a cooling auger is arranged at the outlet of the high-temperature section furnace shell located at the bottom, a powder flow heat exchanger is arranged in the preheating section furnace shell, a heating module is arranged in each high-temperature section furnace shell, the heat exchange medium outlet of the cooling auger is connected to the heat exchange medium inlet of the powder flow heat exchanger through a pipeline, and the heat exchange medium outlet of the powder flow heat exchanger is connected to the heat exchange medium inlet of the cooling auger through a heat circulation pump.

[0007] The beneficial effects of the utility model are as follows: the positive electrode material powder enters the preheating section furnace shell through the inlet on the upper end cover, the positive electrode material powder entering the preheating section furnace shell is preheated by the powder flow heat exchanger, and then enters the high temperature section furnace shell below in turn, and the positive electrode material powder entering the high temperature section furnace shell is heated at high temperature by the heating module in the high temperature section furnace shell, so as to realize the PVDF pyrolysis treatment in the positive electrode material powder, and finally enters the cooling auger, and the cooling auger cools down the high temperature treated positive electrode material powder to meet the subsequent conveying and transportation requirements of the positive electrode material, and the heat exchange medium used by the cooling auger circulates between the cooling auger and the powder flow heat exchanger through the heat circulation pump, and the heat collected in the cooling process is conveyed to the preheating section to preheat the positive electrode material powder, with high thermal efficiency, energy saving and environmental protection;

[0008] The high-temperature section of the structure adopts a modular design and can be stacked in height according to the designed production capacity of the production line to achieve capacity expansion. The equipment selection and layout are flexible and occupy a small area. The material's own weight and the natural fluidization characteristics of the cracking gas during the regeneration process are used to achieve natural flow of materials without additional energy consumption, increase heat exchange, save energy and ensure uniform heating. In addition, the material flows in a dense phase in the furnace, and the space utilization rate in the furnace is high. The device meets the needs of continuous regeneration of lithium battery positive electrode materials. Compared with traditional rotary kilns and roller kilns, it also has the advantages of good sealing and no dust leakage.

[0009] On the basis of the above technical solution, the present invention can also be improved as follows.

[0010] Furthermore, the heating module includes: a heating plate, a plurality of vertical heating plates are arranged in the high-temperature section furnace shell along the horizontal direction at a predetermined interval, a plurality of horizontal channels are opened on the heating plate along its height direction at a predetermined interval, and heating resistors are inserted into the channels on the heating plate.

[0011] The further beneficial effects of adopting the above are:

[0012] When the heating resistor is energized, it can generate heat and transfer the heat to the heating plate to heat the positive electrode material powder falling from between two adjacent heating plates. The heating plate directly heats the positive electrode material powder, with high thermal energy utilization rate. In addition, the material thickness between the heating plates is limited and in a flowing state, so the material is heated more evenly and the product consistency is good.

[0013] Furthermore, the distance between two adjacent heating plates in the high-temperature section furnace shell is 80 mm to 120 mm, and the distance between the heating resistors in adjacent channels on the heating plates is less than 100 mm.

[0014] The further beneficial effects of adopting the above are:

[0015] The distance between two adjacent heating plates is designed to be 80mm to 120mm. The advantages of this distance are as follows: first, it avoids the gap being too small to hinder the material from flowing down due to its own weight; second, it avoids the distance being too large to cause uneven heating of the material, which affects the consistency of product quality;

[0016] The spacing between the heating resistors in adjacent channels on the heating plate is designed to be less than 100 mm. This spacing design can ensure the uniformity of the surface temperature of the heating plate.

[0017] Furthermore, the side wall at the opening of each channel of the heating plate extends outward to form a hollow ceramic column, and the hollow ceramic column is embedded in the inner wall of the high-temperature section furnace shell.

[0018] The further beneficial effects of adopting the above are:

[0019] Embedding the hollow ceramic column into the inner wall of the high-temperature furnace shell can fix and support the heating plate, and prevent the ceramic from cracking due to the inconsistent thermal expansion coefficients of metal and ceramic during metal connection. At the same time, the replacement operation is simple and convenient, and subsequent maintenance / repair / replacement is convenient.

[0020] Furthermore, the heating plate is made of an alumina ceramic plate.

[0021] The further beneficial effects of adopting the above are:

[0022] The use of alumina ceramic plates has the following advantages: smooth surface and low friction coefficient, while avoiding the HF gas generated by the decomposition of PVDF and the reaction with the silicon element in the ceramic, which causes the ceramic material to fail quickly, thus ensuring the service life of the equipment and reducing the equipment failure rate.

[0023] Furthermore, the inner wall of the preheating section furnace shell and the powder flow heat exchanger are made of stainless steel substrate, and the surface of the stainless steel substrate is sprayed with ceramic material; the inner wall of the high temperature section furnace shell is made of alumina ceramic material; the inner wall of the cooling auger cylinder is inlaid with ceramic material, and the surface of the spiral shaft of the cooling auger is sprayed with ceramic material.

[0024] The above further beneficial effects are: the all-ceramic contact surface is resistant to high temperature and corrosion, and can isolate magnetic foreign matter.

[0025] Furthermore, a nitrogen purge port is opened on the cooling auger.

[0026] The above further beneficial effect is that the nitrogen purge port on the cooling auger can provide nitrogen protection for the high-temperature material in the cooling auger, thereby preventing the high-temperature lithium iron phosphate powder from contacting with air (mainly oxygen) during the production of lithium iron phosphate powder, causing oxidation failure of the material.

[0027] Furthermore, the cooling auger adopts a double-axis spiral structure; the motor used by the cooling auger is a variable frequency motor.

[0028] The above further beneficial effects are: utilizing the mutual arch-breaking effect of the double-axis spiral to prevent the high-temperature material from shrinking when cooled and adhering to the cold spiral shaft, which would cause equipment stability failure of the cooling auger due to unstable conveying efficiency; the material discharge speed can be controlled, thereby achieving control of the reaction time of the material in the furnace.

[0029] Furthermore, a discharge shut-off fan is installed at the discharge port of the cooling auger.

[0030] The above further beneficial effects are: the discharge fan is used to discharge the material after high-temperature degumming, and isolates and prevents external air from entering the interior of the cooling auger.

[0031] Furthermore, a material level meter for monitoring the accumulation height of materials in the furnace is installed on the upper end cover.

[0032] The above method has the further beneficial effect of preventing the material from being compacted in the furnace due to excessively fast feeding, which results in decreased material fluidity and disrupts production continuity. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a first structural diagram of the positive electrode material ceramic powder flow regeneration device in the utility model;

[0034] Figure 2 This is a second structural diagram of the positive electrode material ceramic powder flow regeneration device in the utility model;

[0035] Figure 3 This is a diagram showing the coordination of the furnace shell and heating module in the medium and high temperature section of the utility model;

[0036] Figure 4 It is a structural diagram of the heating plate in the utility model.

[0037] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0038] 1. Preheating section furnace shell, 2. High temperature section furnace shell, 3. Cooling auger, 310, nitrogen purge port, 4. Powder flow heat exchanger, 5. Heating module, 510, heating plate, 511, channel, 520, heating resistor, 530, hollow ceramic column, 6. Heat circulation pump, 7. Discharge fan, 8. Upper end cover, 9. Material level meter. DETAILED DESCRIPTION

[0039] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0040] Example 1

[0041] like Figure 1 , Figure 2 As shown, a positive electrode material ceramic powder flow regeneration device comprises:

[0042] A preheating furnace shell 1, an upper end cover 8 is arranged at the top entrance of the preheating furnace shell 1, at least one high-temperature furnace shell 2 is sequentially stacked at the bottom exit of the preheating furnace shell 1, and a cooling auger 3 is arranged at the exit of the bottom high-temperature furnace shell 2 among all the high-temperature furnace shells 2, and the cooling auger 3 is used to cool down the lithium battery positive electrode material powder that has been treated at high temperature to meet the subsequent conveying and transportation requirements of the positive electrode material;

[0043] A powder flow heat exchanger 4 is arranged in the preheating section furnace shell 1, and the powder flow heat exchanger 4 preheats the positive electrode material powder entering the preheating section furnace shell 1. A heating module 5 is arranged in each high temperature section furnace shell 2, and the heating module 5 in the high temperature section furnace shell 2 is used to heat the positive electrode material powder entering the high temperature section furnace shell 2 at high temperature;

[0044] The heat exchange medium outlet of the cooling auger 3 is connected to the heat exchange medium inlet of the powder flow heat exchanger 4 through a pipeline, and the heat exchange medium outlet of the powder flow heat exchanger 4 is connected to the heat exchange medium inlet of the cooling auger 3 through a heat circulation pump 6. The heat exchange medium used by the cooling auger 3 circulates between the cooling auger 3 and the powder flow heat exchanger 4 through the heat circulation pump 6, and the heat collected during the cooling process is transported to the preheating section to preheat the positive electrode material powder, which has high thermal efficiency and is energy-saving and environmentally friendly.

[0045] The utility model utilizes the natural fluidization characteristics of the material's own weight and the cracking gas in the regeneration process to achieve natural flow of the material without additional energy consumption, increase heat exchange, save energy and ensure uniform heating.

[0046] Example 2

[0047] like Figure 3 As shown, this embodiment is a further improvement on the basis of embodiment 1, and the details are as follows:

[0048] The heating module 5 includes: a heating plate 510, a plurality of heating plates 510 are vertically arranged in the high-temperature section furnace shell 2, and the heating plates 510 in the high-temperature section furnace shell 2 are horizontally distributed at a predetermined interval; a plurality of horizontal channels 511 are formed through the heating plate 510, and the channels 511 on the heating plate 510 are distributed at a predetermined interval along its height direction; a heating resistor 520 is inserted into the channel 511 on the heating plate 510, and the heating resistor 520 is energized to generate heat and transfer the heat to the heating plate 510, so as to heat the positive electrode material falling from between two adjacent heating plates 510.

[0049] The heating resistor 520 includes but is not limited to resistance heating elements such as resistance wire, resistance belt, silicon carbon rod, etc. The heating plate 510 is made of alumina ceramics by integral sintering.

[0050] Example 3

[0051] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on the basis of embodiment 2, and the details are as follows:

[0052] The spacing between two adjacent heating plates 510 in the high-temperature furnace shell 2 is 80 mm to 120 mm. The advantages of designing this spacing are as follows: first, it avoids the gap being too small to hinder the material from flowing down by its own weight; second, it avoids the distance being too large to cause uneven heating of the material, affecting the consistency of product quality.

[0053] Furthermore, the spacing between the heating resistors 520 in adjacent channels 511 on the heating plate 510 is less than 100 mm. This spacing design can ensure the uniformity of the surface temperature of the heating plate 510.

[0054] Example 4

[0055] like Figure 4 As shown, this embodiment is a further improvement on the basis of Embodiment 2 or 3, and the details are as follows:

[0056] The side wall at the opening of each channel 511 of the heating plate 510 extends outward to form a hollow ceramic column 530, and the hollow ceramic column 530 is embedded in the inner wall of the high-temperature section furnace shell 2. Embedding the hollow ceramic column 530 in the inner wall of the high-temperature section furnace shell 2 can fix and support the heating plate 510, and can prevent the ceramic from being cracked due to the inconsistent thermal expansion coefficients of metal and ceramic during the connection of metal parts. At the same time, the replacement operation is simple and convenient, and subsequent maintenance / inspection / replacement is convenient.

[0057] Example 5

[0058] like Figure 3 , Figure 4As shown, this embodiment is a further improvement on any one of Embodiments 2 to 4, and the details are as follows:

[0059] The heating plate 510 preferably uses an alumina ceramic plate and avoids using silicon-containing ceramic materials such as mullite and aluminum silicate. The use of an alumina ceramic plate has the following advantages: a smooth surface and a small friction coefficient, while avoiding the decomposition of PVDF to produce HF gas that reacts with the silicon element in the ceramic, causing the ceramic material to fail quickly, thereby ensuring the service life of the equipment and reducing the equipment failure rate.

[0060] Example 6

[0061] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on the basis of Embodiment 5, and the details are as follows:

[0062] The inner wall of the preheating furnace shell 1 is a stainless steel substrate, and the powder flow heat exchanger 4 is a stainless steel substrate. The surface of the stainless steel substrate is sprayed with ceramic material, which can achieve the purpose of isolating the positive electrode material powder from contacting the stainless steel substrate and preventing the introduction of magnetic foreign matter and impurity elements such as Cr, Ni, and Fe. At the same time, it can greatly improve the wear resistance of the material surface and extend the service life. The ceramic material includes but is not limited to tungsten carbide ceramics, aluminum oxide ceramics, titanium oxide ceramics, aluminum titanium ceramics and other ceramic powders, and tungsten carbide ceramics and aluminum titanium ceramics are preferably used;

[0063] The inner wall of the high-temperature furnace shell 2 is made of alumina ceramic material, which has a smooth surface and a low friction coefficient. It can also prevent HF gas generated by PVDF decomposition from reacting with silicon in the ceramic, causing the ceramic material to fail quickly, thereby ensuring the service life of the equipment and reducing the equipment failure rate.

[0064] The inner wall of the cylinder of the cooling auger 3 is inlaid with ceramic material, and the surface of the spiral shaft of the cooling auger 3 is sprayed with ceramic material to prevent the positive electrode material from contacting with the metal matrix (stainless steel material) to introduce magnetic foreign matter or impurity elements;

[0065] The device adopts a full ceramic contact surface, which has the functions of high temperature resistance, corrosion resistance, and isolation of magnetic foreign matter (less impurities introduced).

[0066] Example 7

[0067] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 6, and the details are as follows:

[0068] The cooling auger 3 is provided with a nitrogen purge port 310, through which nitrogen protection can be provided to the high-temperature material to prevent the high-temperature lithium iron phosphate powder from contacting with air (mainly oxygen) during the production of lithium iron phosphate powder, thereby causing oxidation failure of the material.

[0069] Example 8

[0070] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 7, and the details are as follows:

[0071] The cooling auger 3 adopts a double-axis spiral structure, and uses the mutual arch-breaking effect of the double-axis spirals to prevent high-temperature materials from shrinking and adhering to the cold spiral shaft when they are cooled, which would cause equipment stability failure of the cooling auger 3 due to unstable conveying efficiency.

[0072] The motor used by the cooling auger 3 is a variable frequency motor, which can control the material discharge speed, thereby realizing the control of the reaction time of the material in the furnace.

[0073] Example 9

[0074] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 8, and the details are as follows:

[0075] The discharging port of the cooling auger 3 is provided with a discharging fan 7 , which is used for discharging the material after high-temperature degumming and isolating the material from the outside air from entering the interior of the cooling auger 3 .

[0076] Example 10

[0077] like Figure 1 , Figure 2 As shown, this embodiment is a further improvement on any one of Embodiments 1 to 9, and the details are as follows:

[0078] A material level meter 9 is installed on the upper end cover 8 to monitor the material accumulation height in the furnace to prevent the material from being compacted in the furnace due to excessive feeding, resulting in reduced material fluidity and disruption of production continuity.

[0079] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A positive electrode material ceramic powder flow regeneration device, characterized in that: include: A preheating section furnace shell (1), wherein an upper end cover (8) is arranged at the top entrance of the preheating section furnace shell (1), at least one high-temperature section furnace shell (2) is sequentially stacked at the bottom exit of the preheating section furnace shell (1), a cooling auger (3) is arranged at the exit of the high-temperature section furnace shell (2) at the bottom, a powder flow heat exchanger (4) is arranged in the preheating section furnace shell (1), a heating module (5) is arranged in each high-temperature section furnace shell (2), a heat exchange medium outlet of the cooling auger (3) is connected to a heat exchange medium inlet of the powder flow heat exchanger (4) via a pipeline, and a heat exchange medium outlet of the powder flow heat exchanger (4) is connected to a heat exchange medium inlet of the cooling auger (3) via a heat circulation pump (6).

2. A positive electrode material ceramic powder flow regeneration device according to claim 1, characterized in that: The heating module (5) comprises: a heating plate (510); a plurality of vertical heating plates (510) are arranged at a predetermined interval in the horizontal direction in the high-temperature section furnace shell (2); a plurality of horizontal channels (511) are provided through the heating plate (510) at a predetermined interval in the height direction thereof; and a heating resistor (520) is inserted into the channel (511) on the heating plate (510).

3. A positive electrode material ceramic powder flow regeneration device according to claim 2, characterized in that: The distance between two adjacent heating plates (510) in the high-temperature section furnace shell (2) is 80 mm to 120 mm, and the distance between the heating resistors (520) in adjacent holes (511) on the heating plates (510) is less than 100 mm.

4. A positive electrode material ceramic powder flow regeneration device according to claim 2, characterized in that: The side wall at the opening of each hole (511) of the heating plate (510) extends outward to form a hollow ceramic column (530), and the hollow ceramic column (530) is embedded in the inner wall of the high-temperature section furnace shell (2).

5. The positive electrode material ceramic powder flow regeneration device according to claim 2, characterized in that: The heating plate (510) is made of an alumina ceramic plate.

6. A positive electrode material ceramic powder flow regeneration device according to claim 5, characterized in that: The inner wall of the preheating section furnace shell (1) and the powder flow heat exchanger (4) are made of a stainless steel substrate, and a ceramic material is sprayed on the surface of the stainless steel substrate; the inner wall of the high temperature section furnace shell (2) is made of alumina ceramic material; the inner wall of the cylinder of the cooling auger (3) is inlaid with ceramic material, and the surface of the spiral shaft of the cooling auger (3) is sprayed with ceramic material.

7. The positive electrode material ceramic powder flow regeneration device according to claim 1, characterized in that: The cooling auger (3) is provided with a nitrogen purge port (310).

8. The positive electrode material ceramic powder flow regeneration device according to claim 1, characterized in that: The cooling auger (3) adopts a double-axis spiral structure, and the motor used by the cooling auger (3) is a variable frequency motor.

9. The positive electrode material ceramic powder flow regeneration device according to claim 1, characterized in that: The discharge port of the cooling auger (3) is equipped with a discharge fan (7).

10. The positive electrode material ceramic powder flow regeneration device according to claim 1, characterized in that: The upper end cover (8) is provided with a material level meter (9) for monitoring the material accumulation height in the furnace.

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