Continuous graphitization furnace

Abstract

The utility model provides a continuous graphitization furnace, which comprises: a box body, which is transversely arranged and is provided with a feed inlet close to the first end and a discharge outlet close to the second end; the feeding device is arranged on the box body, is connected with the feeding hole of the box body and is used for feeding materials into the box body; the material pushing device is arranged in the box body, can move relative to the box body and is used for pushing materials in the box body from the feeding port to the discharging port; and the discharging device is arranged below the box body, is connected with the discharging opening, and is used for receiving the graphitized material and cooling the material. According to the continuous graphitization furnace, continuous production of an artificial graphite negative electrode material can be realized, the energy consumption is reduced, and the graphitization efficiency is improved.

Description

Technical Field

[0001] This application belongs to the field of graphitization furnace technology, and particularly relates to a continuous graphitization furnace for producing artificial graphite anode materials. Background Technology

[0002] The graphitization furnace for artificial graphite anode materials is an important piece of equipment used in the graphitization process. The maximum operating temperature of the graphitization furnace can reach over 3100 degrees Celsius. It is currently the most important equipment in the production of artificial anode materials. The main types include Atchison furnaces, internal series furnaces, and box furnaces. The ease of graphitization of the material is the main factor affecting the power consumption of the graphitization process.

[0003] In the production of artificial graphite anode materials, existing graphitization furnaces all employ intermittent operation. The material to be graphitized is placed in a crucible or a box-like structure composed of plates. Carbon black is used to insulate the bottom from the current, and the plates and crucible are kept warm using calcined coke. Low-voltage DC current is directly applied, and the material itself and the resistive material are used for heating, raising the material to over 3000 degrees Celsius. Under these high-temperature conditions, the material undergoes a graphitization reaction. After completion, the power is cut off to allow cooling, which typically takes 15-20 days. Once the material temperature has decreased, the material is removed from the crucible or box. This intermittent operation results in a long production cycle, and due to the high temperatures, the crucible's lifespan is generally only three uses, leading to significant losses. Furthermore, the production is discontinuous and inefficient. The residual heat from the graphitized material cannot be utilized and must be dissipated into the surrounding environment for cooling. During the material removal process, the material oxidizes upon contact with air, increasing its specific surface area, which is detrimental to extending the lifespan of lithium-ion batteries. Utility Model Content

[0004] In view of at least one of the above-mentioned technical problems in the prior art, the present application provides a continuous graphitization furnace with a simple and reasonable structure, low energy consumption, and improved graphitization efficiency.

[0005] The technical solution adopted in this application embodiment is: a continuous graphitization furnace, comprising:

[0006] The box body is arranged horizontally, and the box body is provided with a feed inlet near its first end and a discharge inlet near its second end;

[0007] A feeding device is provided on the box body and connected to the feeding port of the box body for feeding materials into the box body;

[0008] A pushing device is disposed inside the box and is movable relative to the box, used to push the material inside the box from the feed inlet toward the discharge outlet.

[0009] The discharge device is located below the box and connected to the discharge port. It is used to receive the graphitized material and cool the material.

[0010] In an optional embodiment, the box body is made of calcined carbon blocks, which are connected by grooves and sealed with asphalt as an adhesive.

[0011] In an optional embodiment, the housing includes a feeding section, a graphitization section, a heat dissipation section, and a discharging section that are sequentially arranged and connected from its first end to its second end; the feeding port is located on the feeding section; and the discharging port is located on the discharging section.

[0012] The graphitized section is provided with an insulation layer made of carbon black on its exterior; the resistivity of the insulation layer is designed to be ≥2000Ω; the thickness of the bottom layer of the graphitized section is ≥700mm, the thickness of the sides is ≥600mm, and the thickness of the top layer is ≥800mm.

[0013] In an optional embodiment, the carbon block of the heat dissipation section has a hollow structure, and a heat exchange tube is embedded inside the carbon block, with a cooling medium flowing inside the heat exchange tube.

[0014] In an optional embodiment, the feeding device includes a storage bin, a conveying pipe, and a feeder. The storage bin is located above the inlet and is connected to the inlet through the conveying pipe. The feeder is located on the conveying pipe.

[0015] The pushing device includes a pushing plate and a pushing rod. The pushing plate is vertically arranged and its outer periphery is movably and sealingly connected to the inner wall of the box. The pushing rod is connected to the pushing plate and extends out of the box from the first end of the box.

[0016] The discharge device includes a discharge baffle located in the discharge section of the box. The discharge baffle is vertically arranged and its outer periphery is movably and sealingly connected to the inner wall of the box. A pull rod is connected to the discharge baffle. One end of the pull rod extends out of the box from the second end of the box and is connected to a power device.

[0017] In an optional embodiment, the discharge device further includes a receiving tank, the opening of which is connected to the discharge port, so that the graphitized and cooled material enters the receiving tank through the discharge port;

[0018] The receiving tank has a double-layer structure with a sandwich layer between the two layers, and a cooling medium flows through the sandwich layer.

[0019] In an optional embodiment, multiple cooling plates are staggered from top to bottom on opposite tank walls of the receiving tank. The free ends of the multiple cooling plates extend toward the center of the receiving tank and slope downwards. Cooling pipes are provided on the back of each of the multiple cooling plates. In an optional embodiment, an inert gas inlet is provided on the feeding section of the box body for introducing inert gas into the box body.

[0020] The graphitized section of the box body is provided with an exhaust port;

[0021] The graphitized section of the box is provided with a pressure relief hole.

[0022] In an optional embodiment, the pusher plate, push rod, discharge baffle, and pull rod are all hollow structures, and a cooling medium flows through the hollow structure.

[0023] In an optional embodiment, the graphitization section has graphitization electrodes on its box wall for passing direct current through the material to generate heat from the material itself.

[0024] Compared with the prior art, the beneficial effects of the embodiments of this application are as follows: the continuous graphitization furnace of the embodiments of this application enables the continuous production of artificial graphite anode materials, and recovers energy from the graphitized material. At the same time, the material is graphitized and discharged in an inert environment, which reduces the risk of material surface oxidation and reduces the specific surface area of ​​artificial graphite anode materials.

[0025] It should be understood that the foregoing general description and the following detailed description are exemplary and illustrative only, and are not intended to limit this application.

[0026] The overview of various implementations or examples of the technology described in this application is not a full disclosure of the entire scope or all features of the disclosed technology. Attached Figure Description

[0027] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The drawings generally illustrate various embodiments by way of example rather than limitation and are used, together with the description and claims, to illustrate the disclosed embodiments. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0028] Figure 1 This is a schematic diagram of the continuous graphitization furnace according to an embodiment of this application.

[0029] Figure 2 This is a schematic diagram of the back structure of the cooling plate according to an embodiment of this application.

[0030] Figure label:

[0031] 1-Box body; 11-Feeding section; 12-Graphitization section; 13-Heat dissipation section; 14-Discharge section; 15-Inert gas inlet; 16-Exhaust port; 17-Pressure relief hole; 18-Insulation layer; 19-Discharge port;

[0032] 2-Feeding device; 21-Storage bin; 22-Conveying pipe; 23-Feeder;

[0033] 3-Pushing device; 31-Pushing plate; 32-Push rod;

[0034] 4-Discharge device; 41-Discharge baffle; 42-Pull rod; 43-Receiving tank; 44-Cooling plate; 45-Cooling pipe; 46-Soft water inlet; 47-Soft water outlet; 48-Rotary discharge valve;

[0035] 5-Graphitized electrode. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the described embodiments of this application without creative effort are within the scope of protection of this application.

[0037] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0038] To keep the following description of the embodiments of this application clear and concise, detailed descriptions of known functions and known components are omitted.

[0039] This application provides a continuous graphitization furnace for producing artificial graphite anode materials.

[0040] like Figure 1 As shown, the continuous graphitization furnace includes a housing 1, a feeding device 2, a pushing device 3, and a discharging device 4. The housing 1 is arranged horizontally, with a feeding port near its first end and a discharging port 19 near its second end. The feeding device 2 is located on the housing 1 and connected to the feeding port, used to feed material into the housing 1. The pushing device 3 is located inside the housing 1 and can move relative to the housing 1, used to push the material inside the housing 1 from the feeding port towards the discharging port 19. The discharging device 4 is located below the housing 1 and connected to the discharging port 19, used to receive the graphitized material and cool it.

[0041] This application utilizes a continuous graphitization furnace, which not only enables continuous production and improves processing efficiency, but also reduces electricity consumption and operating costs during graphitization. Furthermore, it features a simple structure and convenient operation.

[0042] In some embodiments, the housing 1 can be constructed by assembling blocks, which can be made from large-sized calcined charcoal blocks. The charcoal blocks are made by using calcined petroleum coke as raw material and asphalt as a binder. After being mixed evenly, the mixture is extruded and then fired at high temperatures to form high-strength charcoal blocks that can withstand temperatures above 3000 degrees Celsius.

[0043] The thickness of the box 1 is between 400-600mm. The carbon blocks are built by interlocking with each other according to the design requirements. For example, the carbon blocks are connected by customized grooves. At the same time, softened asphalt or phenolic resin is used as an adhesive for bonding and sealing to improve the tightness between the blocks, thereby ensuring the sealing and strength of the box 1.

[0044] In some embodiments, the housing 1 includes a feeding section 11, a graphitization section 12, a heat dissipation section 13, and a discharging section 14, which are sequentially arranged and connected from its first end to its second end. The feeding port is located on the feeding section 11, and the discharging port 19 is located on the discharging section 14. The cross-sectional area of ​​the internal cavity of the housing 1 is approximately rectangular, with a designed width of approximately 1000-1600 mm and a height of approximately 1500-2500 mm. The overall length of the housing 1 is designed to be approximately 15-25 m, of which the feeding section 11 is designed to be approximately 2-3 m, the heat dissipation section 13 and the discharging section 14 together are approximately 4-5 m, and the graphitization section 12 is approximately 9-15 m.

[0045] To maintain the temperature within the graphitization section 12 at 2800-3200℃ and ensure smooth graphitization, a 500-1000mm thick layer of carbon black is laid on the periphery of the graphitization section 12 for insulation. This prevents heat loss during graphitization and maintains the high temperature within the graphitization section 12. Specifically, carbon black is used to form an insulation layer 18, with a resistivity designed to be ≥2000Ω. The thickness of the insulation layer 18 at the bottom of the graphitization section 12 is ≥700mm, the thickness of the insulation layer 18 on the sides is ≥600mm, and the thickness of the insulation layer 18 at the top is ≥800mm.

[0046] In some embodiments, the carbon block of the heat dissipation section 13 has a hollow structure, inside which a high-temperature resistant heat exchange tube is installed. A cooling medium flows through the heat exchange tube, exchanging heat with the material to rapidly reduce its temperature. Optionally, the heat exchange tube is made of alloy steel pipe, through which soft water flows. Heat is exchanged between the carbon block and the material, and between the carbon block and the soft water embedded in the alloy steel pipe, carrying away heat and cooling the material. Simultaneously, the soft water absorbs the waste heat from the high-temperature material, raising its temperature and achieving energy recovery and utilization.

[0047] like Figure 1 As shown, the feeding device 2 includes a storage bin 21, a conveying pipe 22, and a feeder 23. The storage bin 21 is located above the inlet and is connected to the inlet via the conveying pipe 22. The feeder 23 is located on the conveying pipe 22. The storage bin 21 contains graphitized raw materials, which fall through the feeder 23 and enter the feeding section 11 of the housing 1, thus achieving feeding. The feeder 23 can be a star-shaped feeder, i.e., a sealed plug valve.

[0048] Continue to combine Figure 1 The feeding device 3 includes a feeding plate 31 and a push rod 32. The feeding plate 31 is vertically arranged, and its outer periphery is movably and sealingly connected to the inner wall of the box 1. The push rod 32 is connected to the feeding plate 31 and extends out of the box 1 from its first end. Under the action of the push rod 32, the feeding plate 31 pushes the material towards the graphitization section 12 of the box 1, and uses the material to insulate against the high temperature transmitted from the graphitization section 12.

[0049] like Figure 1As shown, the discharge device 4 includes a discharge baffle 41 located within the discharge section 14 of the housing 1. The discharge baffle 41 is vertically arranged, and its outer periphery is movably and sealingly connected to the inner wall of the housing 1. A pull rod 42 is connected to the discharge baffle 41, with one end of the pull rod 42 extending out of the housing 1 from the second end. By pulling the pull rod 42, the discharge baffle 41 can be moved back and forth within the housing 1. When the graphitized material moves forward under the action of the pusher plate 31 (the first end of the housing 1 is defined as the rear side, and the second end of the housing 1 is defined as the front side), the graphitized material contacts the discharge baffle 41. Under the continued pushing action of the pusher plate 31, the graphitized material pushes the discharge baffle 41 forward, causing the material to fall into the discharge port 19, thus completing the discharge.

[0050] One end of the pull rod 42 extends out of the housing 1 and is connected to the power unit. The power unit drives the pull rod 42 to move the discharge baffle 41 back and forth. For example, during the feeding stage, the power unit can drive the discharge baffle 41 to move to the rear side of the discharge port 19. During the discharge stage, the discharge baffle 41 is not only pushed by the material, but also moves forward under the driving action of the power unit, reducing the pushing resistance of the material and facilitating the discharge.

[0051] In some embodiments, such as Figure 1 As shown, the discharge device 4 also includes a receiving tank 43, the opening of which is connected to the discharge port 19, allowing the graphitized and cooled material to enter the receiving tank 43 through the discharge port 19. The receiving tank 43 has a double-layer structure, forming a sandwich layer between the two layers, within which a cooling medium flows. The cooling medium can be cooling water, which is used to cool the material. Soft water can be used, and the steam generated by the heated cooling water is used in production, thus realizing the recovery and utilization of heat from the graphitized material. Specifically, the lower part of the receiving tank 43 has a soft water inlet 46 communicating with the sandwich layer, and the upper part of the receiving tank 43 has a soft water outlet 47 communicating with the sandwich layer, thereby achieving the circulation of cooling water within the sandwich layer. In addition, the receiving tank 43 can be filled with high-purity argon protective gas for protection.

[0052] Continue to combine Figure 1 Multiple cooling plates 44 are staggered from top to bottom on opposite tank walls of the receiving tank 43. The free ends of the cooling plates 44 extend towards the center of the receiving tank 43 and slope downwards. Material falling into the receiving tank 43 through the discharge port 19 is evenly spread onto the cooling plates 44 and slides sequentially across the cooling plates 44 until it reaches the bottom of the tank. During this sliding process, the material exchanges heat with the water in the pipes, cooling it to below 200 degrees Celsius, and finally flows out through the rotary discharge valve 48.

[0053] It is understandable that the number of cooling plates 44 is set according to the required discharge temperature. When the required discharge temperature is low, the discharge temperature of the material can be reduced by increasing the number of cooling plates 44 to extend the sliding time.

[0054] The front of the cooling plate 44 can be a smooth mirror surface to facilitate the smooth sliding of materials. For example... Figure 2 As shown, a cooling pipe 45 is provided on the back side of the cooling plate 44, so that the material can exchange heat with the cooling medium in the cooling pipe 45 while sliding on the front side, thereby cooling the material. The cooling pipe 45 can cover the entire back panel surface and be arranged in a meandering manner to improve cooling efficiency.

[0055] In some embodiments, such as Figure 1 As shown, the feed section 11 of the housing 1 is equipped with an inert gas inlet 15, through which inert gas is introduced into the housing 1. The inert gas can be high-purity argon, with a purity ≥99.99%. During startup, the argon gas replaces the gas inside the entire housing 1, isolating it from air and maintaining an inert environment inside the housing 1. After normal startup, a certain flow rate is maintained, and argon gas needs to be continuously introduced to maintain a slight positive pressure and inert atmosphere.

[0056] Since the graphitization temperature of chamber 1 is between 2800-3200℃, inert gases such as argon are introduced into chamber 1 through inert gas inlet 15 as a protective gas to prevent oxidation of the internal materials, avoid pitting on the surface of the materials due to oxidation, reduce the specific surface area of ​​the materials, and meet the usage requirements.

[0057] Continue to combine Figure 1 The graphitization section 12 of the housing 1 is equipped with an exhaust port 16 and a pressure relief hole 17 (or emergency exhaust hole). During the graphitization process, the volatile components of the material are discharged through the exhaust port 16. The collected gas, after purification, can be used for power generation or as fuel, achieving recycling. The pressure relief hole 17 can automatically open when the internal air pressure of the housing 1 is detected to be too high, to ensure safety during the production process.

[0058] In some embodiments, the pusher plate 31, push rod 32, discharge baffle 41, and pull rod 42 are all hollow structures, with a cooling medium flowing inside to cool them individually. The pusher plate 31, push rod 32, discharge baffle 41, and pull rod 42 are all made of alloy steel with a high temperature resistance of ≥1000℃. Specifically, the pusher plate 31 and push rod 32 can both be made of high-temperature resistant chromium-nickel austenitic stainless steel, nickel-based high-temperature alloy steel, or cobalt-based high-temperature alloy steel. The cooling medium inside the pusher plate 31 and push rod 32 can be soft water, which vaporizes to generate steam that escapes and carries away heat while maintaining the strength of the metal. The discharge baffle 41 and pull rod 42 can be made of inorganic materials or high-temperature alloys, such as silicon carbide or carbon fiber composite materials, and the cooling medium for the discharge baffle 41 and pull rod 42 can be cooling water.

[0059] This application introduces direct current into the material, utilizing the material's own resistance to generate heat. For example, such as... Figure 1 As shown, graphitization electrodes 5 are provided on the wall of the graphitization section 12. Direct current is passed through the graphitization electrodes 5 to the material, and the current generates heat when it passes through the material, heating the material to 2800-3200℃. Furthermore, circulating cooling water can be introduced into the graphitization electrodes 5 to cool them down, thereby extending the service life of the graphitization electrodes 5.

[0060] Before the continuous graphitization furnace is started, the pusher plate 31 is located behind the feed inlet, and the discharge baffle 41 is located behind the discharge port 19. After the continuous graphitization furnace is started, the material falls from the storage bin 21 to the feed section 11. Every once in a while, the pusher plate 31 pushes the material into the graphitization section 12. The material moves forward through the squeezing action between the materials. The pusher plate 31 then returns to the position behind the feed inlet. The temperature of the material in direct contact with the pusher plate 31 is relatively low. The volatiles escaping from the graphitization section 12 are discharged through the exhaust port 16 and can be used as fuel. During the extrusion process, the graphitized material pushes the discharge baffle 41 forward, opening the discharge port 19. The material is then dispersed on the cooling plate 44 of the receiving tank 43 through the discharge port 19. It exchanges heat with the cooling water in the cooling pipe 45 on the cooling plate 44, recovering heat and reducing the temperature of the material. The material is finally discharged from the bottom outlet of the receiving tank.

[0061] The above description is intended to be illustrative and not restrictive. Those skilled in the art can make variations, modifications, substitutions, and alterations to the above embodiments within the scope of this disclosure. Moreover, the above examples (or one or more of them) can be used in combination with each other, and these embodiments can be combined with each other in various combinations or arrangements.

Claims

1. A continuous graphitization furnace characterized by, The application relates to a graphite furnace, which comprises a box body arranged in a transverse direction, a feeding port arranged near a first end of the box body and a discharging port arranged near a second end of the box body, a feeding device arranged above the box body and connected with the feeding port of the box body, a pushing device arranged in the box body and capable of moving relative to the box body, a discharging device arranged below the box body and connected with the discharging port, and the box body is made of calcined carbon blocks, the carbon blocks are connected through concave-convex grooves and are sealed by bitumen as a binder. The box body comprises a feeding section, a graphitization section, a heat dissipation section and a discharging section arranged in sequence and communicated from the first end to the second end of the box body; the feeding port is arranged on the feeding section; the discharging port is arranged on the discharging section; the outer part of the graphitization section is provided with a heat preservation layer formed by carbon black. The resistivity of the heat preservation layer is designed to be greater than or equal to 2000 omega; the bottom of the graphitization section is arranged with a thickness greater than or equal to 700 mm, the side of the graphitization section is arranged with a thickness greater than or equal to 600 mm, and the top of the graphitization section is arranged with a thickness greater than or equal to 800 mm. The carbon blocks of the heat dissipation section are hollow structures, the heat dissipation section is filled with heat exchange pipes, and the heat exchange pipes are filled with cooling medium. The feeding device comprises a storage bin, a feeding pipe and a feeder; the storage bin is arranged above the feeding port and is communicated with the feeding port through the feeding pipe; the feeder is arranged on the feeding pipe; and / or The pushing device comprises a pushing plate and a pushing rod; the pushing plate is arranged in a vertical direction and is movably and sealingly connected with the inner wall of the box body; the pushing rod is connected with the pushing plate and extends out of the box body from the first end of the box body and is connected with a power device; and / or The discharging device comprises a discharging baffle arranged in the discharging section of the box body; the discharging baffle is arranged in a vertical direction and is movably and sealingly connected with the inner wall of the box body; the discharging baffle is connected with a pulling rod; one end of the pulling rod extends out of the box body from the second end of the box body and is connected with a power device. The discharging device further comprises a receiving tank; the tank opening of the receiving tank is connected with the discharging port so that the material after graphitization and cooling enters the receiving tank through the discharging port.

2. The continuous graphitization furnace of claim 1, wherein The receiving tank adopts a double-layer structure, a sandwich layer is formed between the double layers, and the sandwich layer is filled with cooling medium.

3. The continuous graphitization furnace of claim 1, wherein A plurality of cooling plates are arranged on the opposite tank walls of the receiving tank in a staggered manner from top to bottom; the free ends of the plurality of cooling plates extend towards the middle part of the receiving tank and are inclined downward; and the back surfaces of the plurality of cooling plates are respectively provided with cooling pipes.

4. The continuous graphitization furnace of claim 1, wherein The box body is provided with an inert gas inlet for introducing inert gas into the box body. The box body is provided with an exhaust port on the graphitization section. The box body is provided with a pressure relief hole on the graphitization section.

5. The continuous graphitization furnace of claim 4, wherein The pushing plate, the pushing rod, the discharging baffle and the pulling rod are all hollow structures, and the hollow structures are filled with cooling medium. ​ 6. The continuous graphitization furnace of claim 5, wherein ​ 7. The continuous graphitization furnace of claim 1, wherein ​ ​ ​ 8. The continuous graphitization furnace of claim 4, wherein ​ 9. The continuous graphitization furnace of claim 1, wherein, The graphite section is provided with graphite electrodes on the box wall, which is used for passing direct current into the material to make the material self-heating.

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