Continuous vacuum graphitization furnace for battery graphite cathode material

Abstract

The invention discloses a continuous vacuum graphitization furnace for a battery graphite negative electrode material in the technical field of graphitization furnaces, the continuous vacuum graphitization furnace comprises a feeding chamber, a high-temperature graphitization chamber and a cooling discharging chamber, a first gate valve is fixedly arranged in the feeding chamber, and the first gate valve is used for dividing an inner cavity of the feeding chamber into a feeding cavity and a material preparation cavity; a heating assembly is fixedly arranged in the high-temperature graphitization chamber, and a heating cavity communicated with the material preparation cavity is formed in the heating assembly. The graphitization furnace cannot provide a certain vacuum environment for the materials to improve the quality of finished products when processing the materials, but for the graphitization furnace capable of realizing continuous production, the uniformity of the overall temperature of the materials in the furnace and the accurate processing duration of the materials in the furnace are difficult to guarantee; and the problems of inconsistent quality of finished products, increased energy consumption of equipment, blockage in the furnace and the like are easily caused.

Description

Technical Field

[0001] The invention relates to the technical field of graphitization furnaces, in particular to a continuous vacuum graphitization furnace for battery graphite negative electrode materials. Background Art

[0002] The basic process of producing artificial graphite battery negative electrode materials is to select needle coke, petroleum coke, etc. as the main raw materials, and then go through pre-treatment processes such as crushing, screening, and batching to ensure that the particle size and purity of the raw materials meet the requirements of the graphitization process. The pre-treated raw materials are loaded into the graphitization furnace, usually using the Acheson furnace single furnace repeated production method. When loading the furnace, attention should be paid to the placement and density of the raw materials to ensure uniform temperature distribution in the furnace. Electric current is passed into the furnace through the electrodes, causing the raw materials in the furnace to generate Joule heat, and the temperature gradually increases. When the temperature reaches the predetermined graphitization temperature (usually 2800-3000℃), it is maintained for a period of time to fully graphitize the raw materials. The holding time is generally 20-40 hours.

[0003] In practice, existing graphitization furnaces typically utilize a one-time loading and unloading method for the entire furnace. This operating mode presents numerous drawbacks. Excessive loading can lead to significant temperature differences within the furnace, impacting the overall quality and stability of the processed product. Furthermore, the graphitization furnace's heating, holding, and cooling cycles are lengthy, hindering efficient, continuous industrial production.

[0004] For a graphitization furnace that can achieve continuous production, it is difficult to ensure the uniformity of the overall temperature of the material in the furnace and the accurate processing time of the material in the furnace when processing the material, which affects the consistency of product quality to a certain extent. In the discharge link, the material close to the inner wall of the furnace is affected by factors such as the friction of the furnace wall, and its fluidity is relatively poor. This makes the material close to the inner wall of the furnace stay in the furnace longer than the material in the center, resulting in problems such as reduced quality of the finished product, increased energy consumption of the equipment, and blockage in the furnace. These problems not only affect production efficiency, but also increase production costs, restricting the widespread application of graphitization furnaces in industrial production. Therefore, those skilled in the art provide a continuous vacuum graphitization furnace for battery graphite negative electrode materials to solve the problems raised in the above background technology. Summary of the Invention

[0005] The object of the present invention is to provide a continuous vacuum graphitization furnace for battery graphite negative electrode materials, so as to solve the problems that the existing graphitization furnace is not convenient for achieving efficient continuous production in actual application, and the graphitization furnace cannot provide a certain vacuum environment for the material when processing the material to improve the quality of the finished product. For the graphitization furnace that can achieve continuous production, it is also difficult to ensure the uniformity of the overall temperature of the material in the furnace and the accurate processing time of the material in the furnace, which easily leads to problems such as inconsistent quality of the finished product, increased energy consumption of the equipment and blockage in the furnace.

[0006] To achieve the above-mentioned object, the present invention provides the following technical solution: a continuous vacuum graphitization furnace for battery graphite negative electrode materials, comprising:

[0007] A feed chamber, wherein a first gate valve is fixedly provided therein, wherein the first gate valve is used to separate the inner cavity of the feed chamber into a feed cavity and a preparation cavity;

[0008] A high-temperature graphitization chamber is provided with a heating assembly, a heating chamber is formed inside the heating assembly and is connected to the material preparation chamber, a plurality of sets of central material blanking assemblies and outer ring material blanking assemblies are installed in the heating chamber and are staggered up and down, and a driving member for controlling the synchronous operation of the plurality of sets of central material blanking assemblies and outer ring material blanking assemblies is installed on the high-temperature graphitization chamber;

[0009] A cooling discharge chamber is provided with a second gate valve and a water-cooled heat exchange system. The second gate valve is used to separate the cooling discharge chamber into a cooling discharge chamber and a forced cooling chamber. The water-cooled heat exchange system is used to control the rapid cooling of the material inside the forced cooling chamber. A discharge assembly for quantitative discharge is provided between the heating chamber and the forced cooling chamber.

[0010] Preferably: the heating assembly includes a vertical graphite cylinder and a corundum ceramic brick cylinder fixedly installed inside the high-temperature graphitization chamber, an insulation layer is provided between the graphite cylinder and the corundum ceramic brick cylinder, a medium-frequency heating coil is fixedly installed on the outside of the corundum ceramic brick cylinder, and the top of the corundum ceramic brick cylinder is connected to the preparation chamber through a feed pipe.

[0011] Preferably: the central unloading assembly includes a unloading hopper fixedly installed on the inside of the graphite cylinder, a conveying screw is installed through the center of the unloading hopper, multiple groups of the conveying screws located on the same axis are docked and assembled through connecting parts, and the top conveying screw is connected to the driving part through a connecting part.

[0012] Preferably: the outer ring blanking assembly includes an umbrella-shaped baffle fixedly mounted on the conveying screw, and the outer ring of the baffle is fixedly mounted with multiple groups of spiral blades equidistantly arranged around the central axis through a connecting rod, and the outer sides of the spiral blades are close to the inner wall of the graphite cylinder.

[0013] Preferably, the connecting member comprises two groups of connecting sleeves which are symmetrical in upper and lower directions, the connecting sleeves are detachably connected to the ends of the conveying screws by bolts, and the outer rings of the connecting sleeves are provided with multiple groups of scraping strips close to the surface of the lower hopper via inclined rods.

[0014] Preferably, the driving member includes a first servo motor fixedly mounted on the top of the high-temperature graphitization chamber, the output end of the first servo motor is fixedly mounted with a rotating shaft extending into the interior of the heating chamber, the end of the rotating shaft is detachably connected to the connecting sleeve by a bolt, and the rotating shaft is rotatably connected to the feed pipe.

[0015] Preferably: the unloading assembly includes a second servo motor fixedly installed on one side of the cooling discharge chamber, the output end of the second servo motor is fixedly connected to a rotating rod rotatably connected to the cooling discharge chamber, the rotating rod is located at the bottom discharge port of the heating chamber and has multiple groups of discharge plates fixedly installed on the surface, and the multiple groups of discharge plates are arranged equidistantly around the central axis of the rotating rod.

[0016] Preferably, sensors are installed inside the feed cavity, the preparation cavity and the forced cooling cavity, and the sensors are used to monitor the height of the material inside the cavity.

[0017] Preferably, it also includes:

[0018] A vacuum pumping component is connected to the feeding chamber, the heating chamber and the cooling and discharging chamber.

[0019] Preferably: the vacuum pumping component includes a mechanical pump, a first Roots pump and a second Roots pump arranged in series in sequence, the input end of the mechanical pump is connected to the feed chamber through a first vacuum pipeline with a control valve, the first vacuum pipeline is connected to the heating chamber through a second vacuum pipeline with a control valve, and the second vacuum pipeline is connected to the cooling discharge chamber through a third vacuum pipeline with a control valve.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] The equipment consists of three chambers. During the production process, the equipment can realize automatic continuous feeding and continuous discharging, thereby achieving continuous and efficient production of the graphitizing furnace, effectively saving electricity costs and labor costs, and each chamber can be vacuumed to fully protect the heating and sintering of the material. At the same time, the heating chamber of the equipment is equipped with multiple groups of internal and external conveying components that are staggered up and down. The central spiral feeding structure and the outer ring spiral feeding structure provide multiple feeding channels, which make the distribution of materials inside the shaft more uniform. This multi-channel design can effectively avoid excessive accumulation of materials in a certain area, improve the uniformity of material flow inside the heating chamber, and accurately control the processing residence time of materials inside the heating chamber, thereby reducing temperature differences and processing unevenness caused by uneven material distribution. The setting of the multi-stage center and outer ring alternating feeding structure can effectively reduce the load of the unloading component at the lowest feeding port, reduce the pressure on the lowest component of the heating chamber, and ensure the stable operation of the equipment as a whole. It can also effectively avoid problems such as blockage caused by excessive material flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 This is a first schematic diagram of the structure of the blanking assembly inside the heating chamber of the present invention;

[0024] Figure 3 This is a second schematic diagram of the structure of the blanking assembly inside the heating chamber of the present invention;

[0025] Figure 4 This is an enlarged view of one set of blanking component structures in the present invention.

[0026] Legend:

[0027] 10. Feed chamber; 11. First gate valve; 12. Feed chamber; 13. Preparation chamber; 14. High-temperature graphitization chamber; 15. Heating chamber; 16. Second gate valve; 17. Water-cooled heat exchange system; 18. Cooling discharge chamber; 19. Forced cooling chamber; 110. Feed pipe; 111. Sensor; 112. Control valve; 113. Cooling discharge chamber;

[0028] 20. Heating assembly; 201. Graphite cylinder; 202. Corundum ceramic brick cylinder; 203. Insulation layer; 204. Medium frequency heating coil;

[0029] 30. Center feeding assembly; 301. Feed hopper; 302. Conveying screw; 40. Outer ring feeding assembly; 401. Baffle; 402. Connecting rod; 403. Spiral blade;

[0030] 50. Driving member; 501. First servo motor; 502. Rotating shaft;

[0031] 60. Unloading assembly; 601. Second servo motor; 602. Rotating rod; 603. Material shifting plate;

[0032] 70, connecting piece; 701, connecting sleeve; 702, inclined rod; 703, scraper;

[0033] 80. Vacuum pump assembly; 801. Mechanical pump; 802. First Roots pump; 803. Second Roots pump; 804. First vacuum pipeline; 805. Second vacuum pipeline; 806. Third vacuum pipeline. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0035] See also Figures 1 to 4 In an embodiment of the present invention, a continuous vacuum graphitization furnace for battery graphite negative electrode materials includes a feeding chamber 10, a high-temperature graphitization chamber 14 and a cooling and discharging chamber 113. A first gate valve 11 is fixedly provided inside the feeding chamber 10. The first gate valve 11 is used to separate the inner cavity of the feeding chamber 10 into a feeding chamber 12 and a preparation chamber 13. A heating component 20 is fixedly provided inside the high-temperature graphitization chamber 14. A heating chamber 15 connected to the preparation chamber 13 is formed inside the heating component 20. A plurality of groups of central blanking components 30 and outer ring blanking components 40 arranged in an upper and lower staggered manner are installed in the heating chamber 15. A driving member 50 for controlling the synchronous operation of the plurality of central blanking components 30 and outer ring blanking components 40 is installed on the high-temperature graphitization chamber 14.

[0036] A second gate valve 16 and a water-cooled heat exchange system 17 are fixedly provided inside the cooling discharge chamber 113. The second gate valve 16 is used to separate the cooling discharge chamber 113 into a cooling discharge chamber 18 and a forced cooling chamber 19. The water-cooled heat exchange system 17 is used to control the rapid cooling of the material inside the forced cooling chamber 19. A discharge assembly 60 for quantitative discharge is provided between the heating chamber 15 and the forced cooling chamber 19. The water-cooled heat exchange system 17 mainly includes components such as a cooling water circulation pump, a heat exchanger, a cooling water pipeline and a temperature sensor. During the operation of the graphitization furnace, the high-temperature furnace body transfers heat to the cooling water in the cooling water pipeline by radiation and convection. Under the action of the circulating pump, the cooling water flows through the heat exchanger and releases the absorbed heat to the external environment, thereby realizing effective heat transfer and control of the furnace body temperature. The water-cooled heat exchange system 17 is a mature technology in the prior art and will not be elaborated on here.

[0037] The continuous vacuum graphitization furnace for battery graphite negative electrode materials is designed as a vertical structure. It is mainly composed of three parts: a feeding chamber 10, a high-temperature graphitization chamber 14 (the interior of the high-temperature graphitization chamber 14 can be further divided into three parts: a feeding preheating zone, a high-temperature graphitization zone, and a slow cooling zone), and a cooling and discharging chamber 113. The high-temperature graphitization chamber 14 is designed as a split assembly structure, which is convenient for hoisting during installation. The high-temperature graphitization chamber 14 is designed as a double-layer water-cooled structure, all made of stainless steel 304. Circulating water is passed through the interior of the jacket for cooling to ensure that the high-temperature sealing rubber ring is not baked at high temperature and affects the vacuum seal. The equipment can realize continuous feeding and continuous discharging during the production process. Except for top loading, the material transportation of the remaining steps of the equipment can be automatically controlled. By adding a touch screen and PLC in the existing technology to achieve full automation control, one person can complete the operation. The gate valve in the device can be selected from the existing technology electric gate valve or pneumatic gate valve according to actual use needs.

[0038] When the graphitization furnace is in actual use, the material to be processed is delivered from the sealed loading port on the feed chamber 10 to the feed chamber 12. The first gate valve 11 of the electric control switch is used to control the material to be transported from the inside of the feed chamber 12 to the preparation chamber 13 connected to the heating chamber 15. The material entering the heating chamber 15 is temperature-controlled and processed by the heating component 20. After the processing inside the heating chamber 15 is completed, it is transported to the forced cooling chamber 19 through the unloading component 60 at the bottom for cooling. The second gate valve 16 of the electric control switch is used to control the cooled material inside the forced cooling chamber 19 to be transported to the cooling discharge chamber 18. The material shell inside the cooling discharge chamber 18 is finally discharged through the sealed material taking port at its top.

[0039] When the battery graphite negative electrode material is processed inside the graphitization furnace, the material whose flow is controlled by the first gate valve 11, the unloading assembly 60 and the second gate valve 16 can be processed continuously and efficiently. When the unloading assembly 60 is running to discharge the material, the driving member 50 can be opened synchronously to operate inside the heating chamber 15. The driving member 50 controls the rotation of multiple groups of central unloading assemblies 30 and outer ring unloading assemblies 40 that are equidistantly arranged in an upper and lower manner. The central unloading assembly 30 and the outer ring unloading assembly 40 can effectively prevent the material inside the heating chamber 15 from locally accumulating during the falling process, thereby reducing the temperature difference and processing unevenness caused by uneven material distribution, effectively controlling the uniformity of the material flow inside the heating chamber 15 while avoiding blockage of the material flow.

[0040] In one embodiment, see Figure 1Specifically, the heating component 20 includes a vertical graphite cylinder 201 and a corundum ceramic brick cylinder 202 fixedly installed inside the high-temperature graphitization chamber 14, an insulation layer 203 is provided between the graphite cylinder 201 and the corundum ceramic brick cylinder 202, a medium-frequency heating coil 204 is fixedly installed on the outside of the corundum ceramic brick cylinder 202, and the top of the corundum ceramic brick cylinder 202 is connected to the preparation chamber 13 through the feeding pipe 110.

[0041] No heating power supply is installed outside the feed preheating zone of the high-temperature graphitization chamber 14, and radiation heating is carried out by relying on the graphitization high-temperature zone. An insulation layer 203 is provided outside the preheating zone, which is also conducive to reducing heat loss in the high-temperature zone and improving energy utilization. The insulation material of the preheating zone can be hard graphite fiber composite felt. The outside of the insulation material is a steel furnace frame made of 310S. The insulation layer 203 is designed as a composite structure. The inner layer is a 40mm thick graphite fiber composite felt and the outer layer is a graphite soft felt. The total insulation layer 203 thickness is about 200mm. Inside the insulation layer 203 is a graphite cylinder 201 heating element. The length and diameter of the graphite cylinder 201 heating element are set according to the production requirements. The graphite cylinder 201 heating element relies on the medium frequency heating coil 204 controlled by the magnetic conduction of the external medium frequency power supply to achieve heating, and the maximum temperature can reach 3100 degrees.

[0042] The design of medium frequency heating coils 204 and power supplies is no less than 3, and each medium frequency heating coil 204 and power supply realizes independent temperature control to ensure that the temperature of the high temperature zone in the middle of the high temperature zone reaches above 3000 degrees. The medium frequency heating coil 204 is connected to the medium frequency power supply, and the high temperature graphitization zone and the graphite cylinder 201 heating element are magnetically conductive to generate high temperature through the action of the magnetic field. The medium frequency heating coil 204 and the insulation layer 203 are isolated by a corundum ceramic brick tube 202, so that the entire heating process will not be short-circuited with the insulation material, ensuring heating safety.

[0043] See Figures 1 to 4 Specifically, the central feeding assembly 30 includes a feeding hopper 301 fixedly mounted on the inner side of the graphite cylinder 201, and a conveying screw 302 is installed through the center of the feeding hopper 301. Multiple groups of conveying screws 302 located on the same axis are docked and assembled through a connecting piece 70, and the top conveying screw 302 is connected to the driving member 50 through the connecting piece 70. Among them, the outer ring feeding assembly 40 includes an umbrella-shaped baffle 401 fixedly mounted on the conveying screw 302, and the outer ring of the baffle 401 is fixedly mounted with multiple groups of spiral blades 403 arranged equidistantly around the central axis through a connecting rod 402. Both ends of the connecting rod 402 are fixedly connected to the connecting component, and the outer side of the spiral blade 403 is close to the inner wall of the graphite cylinder 201.

[0044] The operation of the driving member 50 can drive the multiple groups of conveying screws 302 on its axis to rotate through multiple groups of connecting members 70. The rotation of the conveying screw 302 can facilitate the material on the top of the lower hopper 301 to be conveyed downward from the middle thereof. The conveying screw 302 drives the baffle 401 and the spiral blades 403 on its outer ring to rotate. The spiral blades 403 can facilitate the material on the top of the baffle 401 to be conveyed downward from its outer ring. The entire material inside the heating chamber 15 can flow stably along a wavy route when conveyed downward. The rotation of the spiral blades 403 and the conveying screw 302 can not only improve the uniformity of material processing inside the heating chamber 15, but also effectively avoid problems such as blockage during material conveying. At the same time, the arrangement of multiple groups of unloading structures can disperse the falling path of the material and reduce the pressure on the lowest unloading component 60.

[0045] Correspondingly, the connecting member 70 includes two groups of connecting sleeves 701 that are symmetrical in the upper and lower parts. The connecting sleeves 701 are detachably connected to the end of the conveying screw 302 by bolts. The outer ring of the connecting sleeve 701 is equipped with multiple groups of scrapers 703 close to the surface of the lower hopper 301 through the inclined rod 702. The two ends of the inclined rod 702 can be fixedly assembled with the connecting components. The connecting sleeve 701 and the conveying screw 302 rotate together to drive the inclined rod 702 and the scraper 703 to rotate. The inclined rod 702 and the scraper 703 rotate at the top surface of the lower hopper 301 to improve the uniformity of mixing of materials inside the heating chamber 15, and can also effectively avoid accumulation of residues on the top of the lower hopper 301 during transportation. The set connecting sleeve 701 also facilitates the segmented assembly of the conveying component to the interior of the heating component 20.

[0046] The driving member 50 includes a first servo motor 501 fixedly mounted on the top of the high-temperature graphitization chamber 14. A rotating shaft 502 extending into the interior of the heating chamber 15 is fixedly mounted on the output end of the first servo motor 501. The end of the rotating shaft 502 is detachably connected to the connecting sleeve 701 by bolts. The rotating shaft 502 is rotatably connected to the feed pipe 110. The operation of the first servo motor 501 can control the rotation of components such as the connecting member 70 and the conveying screw 302 through the rotating shaft 502 at its output end.

[0047] Specifically, the unloading assembly 60 includes a second servo motor 601 fixedly installed on one side of the cooling discharge chamber 113, and the output end of the second servo motor 601 is fixedly connected to a rotating rod 602 rotatably connected to the cooling discharge chamber 113. The rotating rod 602 is located on the surface of the discharge port at the bottom of the heating chamber 15 and has multiple groups of discharge paddles 603 fixedly installed. The multiple groups of discharge paddles 603 are arranged equidistantly in a circle around the central axis of the rotating rod 602. The lower end of the high-temperature graphitization zone is the slow cooling zone, and an insulation layer 203 is also provided on the outside of the slow cooling zone. The slow cooling zone no longer provides heating power. As the material drops, the temperature gradually drops. The lower end of the slow cooling zone is the paddle discharge port. The discharge speed of the discharge paddle 603 is adjusted by the second servo motor 601, thereby accurately controlling the discharge amount of the discharge port.

[0048] In one embodiment, see Figure 1 The continuous vacuum graphitization furnace for battery graphite negative electrode materials also includes a vacuum pumping component 80, which connects the feed chamber 12, the heating chamber 15 and the cooling and discharging chamber 18. Specifically, the vacuum pumping component 80 includes a mechanical pump 801, a first Roots pump 802 and a second Roots pump 803 arranged in series. The input end of the mechanical pump 801 is connected to the feed chamber 12 through a first vacuum pipeline 804 with a control valve 112, the first vacuum pipeline 804 is connected to the heating chamber 15 through a second vacuum pipeline 805 with a control valve 112, and the second vacuum pipeline 805 is connected to the cooling and discharging chamber 18 through a third vacuum pipeline 806 with a control valve 112.

[0049] The feeding chamber 10 of the continuous vacuum graphitization furnace for battery graphite negative electrode materials includes a vacuum-sealed charging port, a charging height control sensor 111, a plug-in type discharge port, etc. Sensors 111 are installed inside the feeding chamber 12, the preparation chamber 13 and the forced cooling chamber 19. The sensor 111 can be an infrared sensor 111 in the prior art. The sensor 111 is used to monitor the material height inside the cavity. During the charging process, the material to be graphitized is first loaded into the feeding chamber 12 through a conveying pipe. The feeding height is controlled by the charging height control sensor 111 for infrared radiation control. The system sends a signal, and then the total amount of material fed into the feed chamber is realized through the PLC. After loading is completed, the vacuum sealing charging port is closed, the control valve 112 on the vacuum pipeline is opened, and vacuum is then achieved through the mechanical pump 801, the first Roots pump 802 and the second Roots pump 803. The order of vacuum pump opening is to first open the mechanical pump 801. After the vacuum degree is less than 800 Pa, open the first Roots pump 802, and then open the second Roots pump 803. When the vacuum degree reaches 6.7X10-1Pa, it indicates that the vacuum pumping of the feed chamber is completed, and the first gate valve 11 is opened to open the material.

[0050] The high-temperature graphitization chamber 14 is designed with a vacuum pumping line and a control valve 112 on the line. It is also connected to the mechanical pump 801, the first Roots pump 802 and the second Roots pump 803 to achieve vacuuming. Similarly, the order of starting the vacuum pumps for vacuuming is to first turn on the mechanical pump 801. After the vacuum degree is less than 800 Pa, turn on the first Roots pump 802, and then turn on the second Roots pump 803. When the vacuum degree reaches 6.7×10-1 Pa, it indicates that the high-temperature graphitization chamber 14 is completely vacuumed and heating can be achieved.

[0051] The outer cavity of the cooling and discharging chamber 113 can also be designed as a double-walled water-cooling jacket structure, which can further cool the graphitized material. The cooling and discharging chamber 113 is also provided with a corresponding material discharging port at the top. When the temperature detected by the thermocouple of the graphitized material reaches the cooling requirement, air can be introduced when the second gate valve 16 is closed to balance the internal and external pressures. The material discharging port can then be opened and a straw can be inserted to suck out the graphitized material.

[0052] The cooling discharge chamber 18 is designed with a vacuum interface, which is connected to the pump body through a vacuum pipeline and a pipeline control valve 112. Similarly, the chamber can be vacuumed. The vacuum degree of the chamber must be consistent with the vacuum degree of the high-temperature graphitization chamber 14 before the second gate valve 16 can be opened. Otherwise, if air is opened in the cooling discharge chamber 113, air will enter the high-temperature graphitization chamber 14 and affect material production.

[0053] The continuous vacuum graphitization furnace for battery graphite negative electrode materials is a vertical structure with a relatively high equipment height. Therefore, it is recommended to dig a pit for installation and place the base in the pit. It is recommended that the base be about two meters below the ground.

[0054] The equipment can realize continuous feeding and discharging during the production process. The equipment consists of three cavities, each of which can be vacuumed and filled with atmosphere to protect sintering. The specific structure and advantages of the equipment are as follows:

[0055] 1. The overall equipment is a vertical structure with a feeding and transfer bin designed on the top. First, heat the material in the transfer bin and then close the furnace door to evacuate the vacuum. When the vacuum reaches the limit, open the material delivery door connected to the sintering chamber to feed the material. Sensor 111 is used to keep the material inside the blanking and preparation chamber.

[0056] 2. The sintering chamber is a vertical structure. As the material discharge at the bottom decreases, the internal material automatically descends and the upper material automatically fills up, thus realizing continuous production.

[0057] 3. The equipment adopts medium frequency heating method, with a designed maximum temperature of 3100 degrees and an operating temperature of 3000 degrees.

[0058] 4. The bottom of the equipment is designed with a discharge transfer bin. The material coming out will first be slowly cooled in the slow cooling zone at the bottom. After slow cooling, the material will enter the transfer bin and be quickly cooled to the discharge temperature before the discharge transfer bin door can be opened for discharge.

[0059] 5. The effective heating zone diameter of the heating chamber is designed to be 800mm and the effective high temperature zone length is 2000mm. The overall production capacity of the equipment is high and stable.

[0060] 6. The air outlet of the equipment is equipped with environmental protection treatment equipment to achieve environmentally friendly and safe emission standards.

[0061] 7. The equipment reduces electricity costs and labor costs in producing graphite negative electrode materials, and is conducive to improving the yield of products.

[0062] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0063] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A continuous vacuum graphitization furnace for battery graphite negative electrode materials, characterized in that: include: A feed chamber (10) is provided with a first gate valve (11) therein, wherein the first gate valve (11) is used to separate the inner cavity of the feed chamber (10) into a feed cavity (12) and a preparation cavity (13); A high-temperature graphitization chamber (14) is provided with a heating assembly (20) therein, a heating chamber (15) is formed inside the heating assembly (20) and is connected to the material preparation chamber (13), a plurality of groups of central material discharging assemblies (30) and outer ring material discharging assemblies (40) arranged in an upper and lower staggered manner are installed in the heating chamber (15), and a driving member (50) for controlling the synchronous operation of the plurality of groups of central material discharging assemblies (30) and outer ring material discharging assemblies (40) is installed on the high-temperature graphitization chamber (14); A cooling discharge chamber (113) is provided with a second gate valve (16) and a water-cooling heat exchange system (17). The second gate valve (16) is used to separate the cooling discharge chamber (113) into a cooling discharge chamber (18) and a forced cooling chamber (19). The water-cooling heat exchange system (17) is used to control the rapid cooling of the material inside the forced cooling chamber (19). A discharge assembly (60) for quantitative discharge is provided between the heating chamber (15) and the forced cooling chamber (19).

2. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 1, characterized in that: The heating assembly (20) comprises a vertical graphite cylinder (201) and a corundum ceramic brick cylinder (202) fixedly mounted inside a high-temperature graphitization chamber (14); a heat-insulating layer (203) is provided between the graphite cylinder (201) and the corundum ceramic brick cylinder (202); a medium-frequency heating coil (204) is fixedly mounted on the outside of the corundum ceramic brick cylinder (202); and the top end of the corundum ceramic brick cylinder (202) is connected to a material preparation chamber (13) via a feed pipe (110).

3. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 2, characterized in that: The central material discharge assembly (30) includes a material discharge hopper (301) fixedly mounted on the inner side of the graphite cylinder (201), a conveying screw (302) is installed through the center of the material discharge hopper (301), multiple groups of the conveying screws (302) located on the same axis are docked and assembled through a connecting piece (70), and the topmost conveying screw (302) is connected to the driving member (50) through the connecting piece (70).

4. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 3, characterized in that: The outer ring blanking assembly (40) includes an umbrella-shaped baffle (401) fixedly mounted on the conveying screw (302), and the outer ring of the baffle (401) is fixedly mounted with multiple groups of spiral blades (403) arranged equidistantly around the central axis through a connecting rod (402), and the outer sides of the spiral blades (403) are close to the inner wall of the graphite cylinder (201).

5. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 3, characterized in that: The connecting member (70) includes two groups of connecting sleeves (701) symmetrically arranged in an upper and lower direction. The connecting sleeves (701) are detachably connected to the ends of the conveying screw (302) via bolts. The outer ring of the connecting sleeve (701) is equipped with multiple groups of scraping strips (703) close to the surface of the lower hopper (301) via inclined rods (702).

6. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 5, characterized in that: The driving member (50) includes a first servo motor (501) fixedly mounted on the top of the high-temperature graphitization chamber (14); a rotating shaft (502) extending into the interior of the heating chamber (15) is fixedly mounted on the output end of the first servo motor (501); an end of the rotating shaft (502) is detachably connected to the connecting sleeve (701) via a bolt; and the rotating shaft (502) is rotatably connected to the feeding pipe (110).

7. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 1, characterized in that: The unloading assembly (60) includes a second servo motor (601) fixedly mounted on one side of the cooling discharge chamber (113); an output end of the second servo motor (601) is fixedly connected to a rotating rod (602) rotatably connected to the cooling discharge chamber (113); a plurality of groups of discharge paddles (603) are fixedly mounted on the surface of the rotating rod (602) located at the bottom discharge port of the heating chamber (15); and the plurality of groups of discharge paddles (603) are equidistantly arranged in a circle around the central axis of the rotating rod (602).

8. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 1, characterized in that: Sensors (111) are installed inside the feed cavity (12), the preparation cavity (13) and the forced cooling cavity (19), and the sensors (111) are used to monitor the height of the material inside the cavity.

9. A continuous vacuum graphitization furnace for battery graphite negative electrode materials according to any one of claims 1 to 8, characterized in that: Also includes: A vacuum pumping assembly (80) is connected to the feed chamber (12), the heating chamber (15) and the cooling discharge chamber (18).

10. The continuous vacuum graphitization furnace for battery graphite negative electrode materials according to claim 9, characterized in that: The vacuum pumping assembly (80) comprises a mechanical pump (801), a first Roots pump (802) and a second Roots pump (803) which are sequentially connected in series. The input end of the mechanical pump (801) is connected to the feed chamber (12) via a first vacuum pipeline (804) with a control valve (112). The first vacuum pipeline (804) is connected to the heating chamber (15) via a second vacuum pipeline (805) with a control valve (112). The second vacuum pipeline (805) is connected to the cooling discharge chamber (18) via a third vacuum pipeline (806) with a control valve (112).

Images