Continuous graphitization process and reactor with electric heating fluidized bed

Abstract

The application provides an electric heating fluidized bed continuous graphitization reactor, which comprises a first countercurrent cyclone separation device, an electric heating fluidized bed reactor and a second countercurrent cyclone separation device which are linearly communicated in sequence from top to bottom; the top of the first countercurrent cyclone separation device is provided with a solid medium inlet; the bottom of the second countercurrent cyclone separation device is provided with a carrier gas inlet, a graphitization reaction raw material inlet and a solid medium and product outlet. The electric heating fluidized bed continuous graphitization reactor provided by the application connects the first countercurrent cyclone separation device, the electric heating fluidized bed reactor and the second countercurrent cyclone separation device in series to form a new continuous graphitization reactor, wherein the first countercurrent cyclone separation device and the second countercurrent cyclone separation device can not only play a role in controlling feeding and discharging, but also can realize direct utilization of sensible heat in the process of controlling feeding and discharging, so that a heat recovery device is omitted, and the device structure is simple and easy to popularize.

Description

Technical Field

[0001] This invention relates to the field of graphitization technology, and more particularly to an electrically heated fluidized bed continuous graphitization method and reactor. Background Technology

[0002] Artificial graphite, as a negative electrode material for lithium batteries, has advantages such as low cost, high lithium storage capacity, and simple production process, leading to a growing demand in the battery market. The graphitization process for general carbon-based materials often employs Atchison graphitization furnaces or internally heated series graphitization furnaces, which are intermittent furnaces and suffer from problems such as high energy consumption, low production capacity, and severe pollution.

[0003] In recent years, intermittent graphitization furnaces have been gradually replaced by continuous graphitization furnaces. However, existing continuous graphitization furnaces mostly use vertical moving beds, which suffer from low heat transfer efficiency and long heating times. Furthermore, they can only process blocky carbon materials with particle sizes in the millimeter range, and cannot process fine powder carbon materials with particle sizes in the micrometer range. This limits the utilization of continuous graphitization furnaces and significantly reduces their application scope. In addition, a large amount of sensible heat from the outlet material of traditional continuous graphitization furnaces is not recovered or utilized, or the utilization devices are complex and cumbersome, resulting in low energy utilization efficiency and high energy consumption. Summary of the Invention

[0004] To address the aforementioned problems in the existing technology, this invention provides an electrically heated fluidized bed continuous graphitization reactor and a method for graphitizing carbon materials, enabling continuous graphitization production of micron-sized fine powder carbon materials under low energy consumption conditions.

[0005] The specific details of the invention are as follows:

[0006] In a first aspect, the present invention provides an electrically heated fluidized bed continuous graphitization reactor, the reactor comprising a first countercurrent cyclone separator 01, an electrically heated fluidized bed reactor 02, and a second countercurrent cyclone separator 03 that are linearly connected from top to bottom;

[0007] The top of the first countercurrent cyclone separator 01 is provided with a solid medium inlet 1 and a carrier gas outlet 2;

[0008] The bottom of the second countercurrent cyclone separator 03 is provided with a carrier gas inlet 10, a graphitization reaction raw material inlet 9, and a solid medium and finished product outlet 11.

[0009] Optionally, the electrically heated fluidized bed reactor 02 consists of a three-layer furnace lining with a total thickness of 150~300 mm, including an inner layer 14: graphite or magnesia-carbon brick structure, a middle layer 15: carbon felt or diatomaceous earth brick structure, and an outer layer 16: carbon steel structure.

[0010] The electrically heated fluidized bed reactor 02 is equipped with graphite electrodes 17 at different axial heights, extending radially directly into the reactor interior.

[0011] The electrically heated fluidized bed reactor 02 is equipped with a graphite venturi backflush device 24, which is used to introduce carrier gas to prevent carbon powder from adhering and conducting the graphite electrode 17.

[0012] Optionally, the electrically heated fluidized bed reactor 02 is equipped with at least two infrared temperature measuring devices 18 and at least three backflush pressure measuring devices 23 to measure the pressure, material level, dense phase density and temperature parameters of the electrically heated fluidized bed reactor 02.

[0013] Optionally, the electrically heated fluidized bed reactor 02 is connected to the first countercurrent cyclone separator 01 through the fluidized bed solid medium inlet 12 and the fluidized bed carrier gas outlet 13;

[0014] The electrically heated fluidized bed reactor 02 is connected to the second countercurrent cyclone separator 03 through the fluidized bed solid medium outlet 20 and the fluidized bed carrier gas and raw material inlet 21.

[0015] Optionally, a flow regulating valve 19 is provided on the fluidized bed solid medium outlet 20, and the fluidized bed height is controlled by adjusting the valve opening of the flow regulating valve 19;

[0016] The flow regulating valve 19 is made of graphite or carbon-carbon composite material.

[0017] Optionally, the electrically heated fluidized bed reactor 02 is provided with at least one layer of gas distributor 22.

[0018] Optionally, both the first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 are multi-stage countercurrent cyclone separators installed coaxially.

[0019] Both the first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 are equipped with a cyclone separator insulation layer 8.

[0020] Optionally, a heat exchanger 4 is provided at the top of the first countercurrent cyclone separator 01 to ensure that the outlet temperature of the carrier gas is lower than the ignition point of the combustible material formed after the impurities in the graphitization reaction raw material are gasified.

[0021] In a second aspect, the present invention provides an electrically heated fluidized bed continuous graphitization method, the method being applicable to the reactor described in the first aspect above, the method comprising:

[0022] Argon gas is used as the carrier gas to carry the graphitization reaction raw materials, which enter the electrically heated fluidized bed reactor 02 through the second countercurrent cyclone separator 03; the solid medium enters the electrically heated fluidized bed reactor 02 through the first countercurrent cyclone separator 01.

[0023] In the electrically heated fluidized bed reactor 02, the micron-sized carbon black is deposited on the solid medium to form a graphite product;

[0024] The graphite product further descends and enters the second countercurrent cyclone separator 03, where it undergoes countercurrent contact heat exchange with the carrier gas and graphitization reaction raw materials before exiting the second countercurrent cyclone separator 03.

[0025] The carrier gas rises further and enters the first countercurrent cyclone separator 01, where it undergoes countercurrent contact heat exchange with the graphite particles. It then exits the first countercurrent cyclone separator 01 and is recycled and reused through a circulation pipeline.

[0026] Optionally, the solid-gas ratio of the carrier gas to the graphitization reaction raw materials is not less than 20;

[0027] The graphitization reaction raw material is A or B type micron-sized carbon black particles with an average particle size of 10μm~1mm; the solid medium is graphite particles.

[0028] The temperature inside the electrically heated fluidized bed reactor 02 is 2500~3500℃.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] This invention provides an electrically heated fluidized bed continuous graphitization reactor. The reactor includes a first countercurrent cyclone separator 01, an electrically heated fluidized bed reactor 02, and a second countercurrent cyclone separator 03, which are linearly connected from top to bottom. The top of the first countercurrent cyclone separator 01 is provided with a solid medium inlet 1; the bottom of the second countercurrent cyclone separator 03 is provided with a carrier gas inlet 10, a graphitization reaction raw material inlet 9, and a solid medium and finished product outlet 11. The electrically heated fluidized bed continuous graphitization reactor provided by this invention combines the first countercurrent cyclone separator 01, the electrically heated fluidized bed reactor 02, and the second countercurrent cyclone separator 03 in series to form a new continuous graphitization reactor. The first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 can both control the feed and discharge, and directly utilize sensible heat during the feed and discharge process, eliminating the need for a heat recovery device. The device structure is simple and easy to promote.

[0031] This invention enables continuous processing of fine carbon materials with particle sizes in the micrometer range, expanding the application range of graphitization furnaces. Using an electrically heated fluidized bed as the graphitization furnace improves heating efficiency, shortens heating time, and thus increases yield. Furthermore, the invention utilizes a first countercurrent cyclone separator 01 and a second countercurrent cyclone separator 03 to preheat the carrier gas, graphitization reaction raw materials, and solid media, thereby achieving secondary utilization of energy during the reaction process and reducing system energy consumption. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This diagram illustrates the overall structure of the electrically heated fluidized bed continuous graphitization reactor provided in an embodiment of the present invention.

[0034] Figure 2 A schematic diagram of the structure of an electrically heated fluidized bed reactor provided in an embodiment of the present invention is shown.

[0035] Explanation of reference numerals in the attached drawings: 01, First countercurrent cyclone separator; 02, Electrically heated fluidized bed reactor; 03, Second countercurrent cyclone separator; 1, Solid medium inlet; 2, Carrier gas outlet; 3, Carrier gas circulation pipeline; 4, Heat exchanger; 8, Insulation layer; 9, Graphitization reaction raw material inlet; 10, Carrier gas inlet; 11, Solid medium and finished product outlet; 12, Fluidized bed solid medium inlet; 13, Fluidized bed carrier gas outlet; 14, Inner layer; 15, Middle layer; 16, Outer layer; 17, Graphite electrode; 18, Infrared thermometer; 19, Flow regulating valve; 20, Fluidized bed solid medium outlet; 21, Fluidized bed carrier gas and raw material inlet; 22, Gas distributor; 23, Backflush pressure measuring device; 24, Venturi backflush device. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention. Furthermore, all other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of the present invention.

[0037] Specific experimental steps or conditions are not specified in the embodiments; they can be performed according to the conventional experimental steps or conditions described in the prior art. Reagents and other instruments used, unless otherwise specified, are all commercially available conventional reagent products. Furthermore, the accompanying drawings are merely illustrative diagrams of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore, repeated descriptions of them will be omitted. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0038] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0039] In the description of this invention, it should be understood that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0040] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] Before providing a detailed description of the electrically heated fluidized bed continuous graphitization method and reactor provided by this invention, it is necessary to explain the relevant technologies as follows:

[0042] Most existing continuous graphitization furnaces adopt a vertical graphitization furnace structure, characterized by its vertical arrangement. It generally includes a furnace body, heating system, feeding system, discharge system, and control system. The feeding system, located at the top of the furnace body, continuously feeds the raw materials to be graphitized into the furnace. It typically consists of a feed inlet, a feeding device (such as a screw conveyor or vibrator), and a batching system. The discharge system, located at the bottom of the furnace body, continuously discharges the graphitized products from the furnace. It typically includes a discharge outlet and a waste gas treatment device. The furnace body is the main part of the graphitization furnace and is usually constructed of high-temperature resistant materials (such as refractory bricks). The furnace body is divided into multiple graphitization zones and other auxiliary zones for controlling and adjusting various parameters of the graphitization process. The graphitization reaction raw materials supplied by the feeding system are directly converted into graphite products at high temperatures. During continuous graphitization, it is necessary to control the uniform downward movement of solid particles; however, excessively small fine powder particles will float in the reactor, causing malfunctions. Therefore, this structural design can only handle graphitization reaction raw materials with particle sizes in the millimeter range, and cannot handle fine carbon powder with particle sizes in the micrometer range. This limits the use of continuous graphitization furnaces and greatly reduces their application scope.

[0043] In view of this, the present invention provides an electrically heated fluidized bed continuous graphitization reactor, which utilizes a fluidized bed to perform continuous graphitization in a fluidized form. In this reactor, the graphitization reaction raw materials (such as micron-sized fine powder carbon materials) carried by the carrier gas are introduced into the electrically heated fluidized bed reactor from opposite directions, allowing for continuous graphitization while simultaneously exchanging heat through counter-current contact between the components. This achieves direct utilization of sensible heat during continuous feeding and discharge, as well as the recovery and reuse of the carrier gas, thereby improving production efficiency and yield. Furthermore, the thorough mixing and contact between the graphitization reaction raw materials and the carrier gas inside the fluidized bed reactor is beneficial for the graphitization reaction and improves graphitization efficiency. The fluidized bed continuous graphitization reactor can be used for the graphitization of micron-sized solid materials, and has a wide range of applications.

[0044] Figure 1 A schematic diagram of the overall structure of the electrically heated fluidized bed continuous graphitization reactor provided in an embodiment of the present invention is shown, as follows: Figure 1 As shown, the reactor includes a first countercurrent cyclone separator 01, an electrically heated fluidized bed reactor 02, and a second countercurrent cyclone separator 03, which are linearly connected from top to bottom. The first countercurrent cyclone separator 01 has a solid medium inlet 1 and a carrier gas outlet 2 at its top, while the second countercurrent cyclone separator 03 has a carrier gas inlet 10, a graphitization reaction raw material inlet 9, and a solid medium and finished product outlet 11 at its bottom.

[0045] In practice, the components involved in continuous graphitization include a solid medium, a carrier gas, and graphitization reaction raw materials carried by the carrier. The solid medium can be graphite particles, the carrier gas can be argon or nitrogen, and the graphitization reaction raw materials can be micron-sized carbon black. (See also...) Figure 1 The arrows in the diagram indicate the flow direction of the carrier gas in the reactor (solid line) and the flow direction of the solid medium in the system (dashed line). The solid medium first enters the electrically heated fluidized bed reactor 02 through the first countercurrent cyclone separator 01 via the solid medium inlet 1. The carrier gas enters the second countercurrent cyclone separator 03 via the carrier gas inlet 10, where it mixes with the graphitization reaction raw material that enters the second countercurrent cyclone separator 03 via the graphitization reaction raw material inlet 9. The graphitization reaction raw material then rises under the carry of the carrier gas and enters the electrically heated fluidized bed reactor 02.

[0046] Thus, the solid medium enters the electrically heated fluidized bed reactor 02 from top to bottom via the first countercurrent cyclone separator 01, while the graphitization reaction raw materials and carrier gas enter the electrically heated fluidized bed reactor 02 from bottom to top via the second countercurrent cyclone separator 03. It should be noted that before the graphitization reaction raw materials, carried upwards by the carrier gas, enter the electrically heated fluidized bed reactor 02, the temperature of the main reaction zone of the electrically heated fluidized bed reactor 02 is maintained at 2500~3500℃. In this scenario, the solid medium initially entering the electrically heated fluidized bed reactor 02 absorbs heat. As it descends to the second counter-current cyclone separator 03, its high temperature preheats the upward-flowing carrier gas and graphitization reaction raw materials, ensuring their temperature reaches 800-1800°C before entering the reactor 02. Further, the carrier gas carries the graphitization reaction raw materials into the reactor 02, where they deposit on the solid medium to form graphite products. The heated carrier gas continues to ascend to the first counter-current cyclone separator 01, where it engages in counter-current contact heat exchange with the continuously entering solid medium, maintaining a temperature of 900-1800°C before entering the reactor 02. The resulting graphite products then sink into the second counter-current cyclone separator 03, where they engage in counter-current contact heat exchange with the continuously entering carrier gas and graphitization reaction raw materials, preheating both the graphitization reaction raw materials and the carrier gas, directly utilizing sensible heat, and improving energy efficiency. Finally, the carrier gas exits the system from the carrier gas outlet 2 at the top of the first counter-current cyclone separator 01, and re-enters the second counter-current cyclone separator 03 through the circulation pipeline 3 from the carrier gas inlet 10, thus achieving recycling. Furthermore, inert components accumulate during the carrier gas recycling process; excessive accumulation can cause pipeline blockage. This can be avoided by releasing a small amount of gas through the carrier gas outlet 2.

[0047] Compared to conventional methods that involve feeding solid media, carrier gas, and graphitization reaction raw materials into the graphitization furnace from the same direction, recovering sensible heat requires an additional heat exchange device outside the graphitization furnace, resulting in a cumbersome and complex design. Furthermore, the particle size of the graphitization reaction raw materials that can be processed cannot reach the micrometer level. The system provided by this invention changes the conventional design by connecting the first countercurrent cyclone separator 01, the electrically heated fluidized bed reactor 02, and the second countercurrent cyclone separator 03 in series to form a new continuous graphitization reactor. The first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 can both control the feed and discharge, and directly utilize sensible heat during the feed and discharge process, eliminating the need for a recovery device. The device structure is simple and easy to promote.

[0048] Figure 2 A schematic diagram of the structure of the electrically heated fluidized bed reactor provided in an embodiment of the present invention is shown. See also: Figure 2 As shown, the electrically heated fluidized bed reactor 02 provided by the present invention consists of a three-layer lining with a total thickness of 150-300 mm; including an inner layer 14: graphite or magnesia-carbon brick structure, a middle layer 15: carbon felt or diatomaceous earth brick structure, and an outer layer 16: carbon steel structure. This structural design ensures that the electrically heated fluidized bed reactor 02 has good heat preservation, thereby reducing the heat loss of the system. Graphite electrodes 17, extending radially directly into the reactor, are provided at different axial heights in the electrically heated fluidized bed reactor 02 for heating the reactor. A graphite Venturi backflush device 24 is also provided in the electrically heated fluidized bed reactor 02 to introduce carrier gas to prevent carbon powder from adhering to and conducting the graphite electrodes 17. At least two infrared temperature measuring devices 18 and at least three backflush pressure measuring devices 23 are provided inside the electrically heated fluidized bed reactor 02 to measure the pressure, material level, dense phase density, and temperature parameters of the electrically heated fluidized bed reactor 02.

[0049] See Figure 1 and 2 The electrically heated fluidized bed reactor 02 and the first countercurrent cyclone separator 01 are connected via a fluidized bed solid medium inlet 12 and a fluidized bed carrier gas outlet 13. Specifically, the heated carrier gas in the electrically heated fluidized bed reactor 02 rises through the fluidized bed carrier gas outlet 13 to the first countercurrent cyclone separator 01, where it engages in countercurrent contact heat exchange with the continuously entering solid medium, allowing the solid medium to reach a temperature of 900~1800℃ before entering the electrically heated fluidized bed reactor 02. The solid medium enters the electrically heated fluidized bed reactor 02 through the solid medium inlet 12, providing a deposition carrier for the continuous graphitization of graphitization reaction raw materials. Furthermore, before entering the electrically heated fluidized bed reactor 02, the solid medium engages in countercurrent contact heat exchange with the rising carrier gas, thereby transferring the heat carried by the carrier gas to the solid medium and utilizing sensible heat.

[0050] Furthermore, the electrically heated fluidized bed reactor 02 and the second countercurrent cyclone separator 03 are connected via the fluidized bed solid medium outlet 20 and the fluidized bed carrier gas and raw material inlet 21. Specifically, the graphite product and solid medium formed in the electrically heated fluidized bed reactor 02 exit the reactor through the fluidized bed solid medium outlet 20 and enter the second countercurrent cyclone separator 03. There, they come into countercurrent contact with the graphitization reaction raw materials and carrier gas that are continuously entering the system, exchanging heat and allowing the graphitization reaction raw materials and carrier gas to rise further. Before entering the electrically heated fluidized bed reactor 02 through the fluidized bed carrier gas and raw material inlet 21, the temperature can reach 800~1800℃.

[0051] See Figure 2 As shown, a flow regulating valve 19 is provided on the fluidized bed solid medium outlet 20. The fluidized bed height is controlled by adjusting the valve opening of the flow regulating valve 19. Preferably, the flow regulating valve 19 is made of graphite or carbon-carbon composite material.

[0052] See also Figure 2 The electrically heated fluidized bed reactor 02 is equipped with at least one gas distributor 22, so that after the carrier gas carries the graphitization reaction raw materials into the electrically heated fluidized bed reactor 02, the graphitization reaction raw materials are evenly distributed in the carrier gas and the graphitization reaction raw materials carried by the carrier gas are evenly distributed in the main reaction zone of the electrically heated fluidized bed reactor 02, thus ensuring that graphitization is fully carried out.

[0053] In some embodiments, both the first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 are multi-stage countercurrent cyclone separators installed coaxially. Both the first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 consist of at least two countercurrent cyclone separators connected in series to enhance the contact area and contact time between components, thereby increasing heat exchange efficiency and separation efficiency. Furthermore, both the first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 are equipped with a cyclone separator insulation layer 8.

[0054] In some embodiments, a heat exchanger 4 is provided at the top of the first countercurrent cyclone separator 01 to ensure that the temperature at the carrier gas outlet 2 is lower than the ignition point of the combustibles formed after the impurities in the graphitization reaction raw materials are vaporized. Specifically, the heat exchanger can be used to introduce a cooling medium (cooling water or liquid nitrogen) into the top of the cyclone separator to reduce the temperature of the carrier gas at the carrier gas outlet 2 to below 200°C.

[0055] In a second aspect, the present invention provides an electrically heated fluidized bed continuous graphitization method, the method being applicable to the reactor described in the first aspect above, the method comprising:

[0056] Argon gas, carrying the graphitization reaction raw materials, enters the electrically heated fluidized bed reactor 02 via a second countercurrent cyclone separator 03. The solid medium enters the electrically heated fluidized bed reactor 02 via a first countercurrent cyclone separator 01. In the electrically heated fluidized bed reactor 02, the micron-sized carbon black is deposited on the solid medium to form a graphite product. The graphite product further descends and enters the second countercurrent cyclone separator 03, where it undergoes countercurrent contact heat exchange with the carrier gas and the graphitization reaction raw materials before exiting the second countercurrent cyclone separator 03. The carrier gas further ascends and enters the first countercurrent cyclone separator 01, where it undergoes countercurrent contact heat exchange with the graphite particles before exiting the first countercurrent cyclone separator 01 and being recycled and reused through a circulation pipeline.

[0057] In specific implementation, the components involved in the electrothermal fluidized bed continuous graphitization method include a solid medium, a carrier gas, and graphitization reaction raw materials carried by the carrier. The solid medium can be graphite particles, the carrier gas can be argon or nitrogen, and the graphitization reaction raw materials can be micron-sized carbon black. The electrothermal fluidized bed continuous graphitization method provided by this invention is applicable to the electrothermal fluidized bed continuous graphitization system provided in the first aspect above. See [link to relevant documentation]. Figure 1 The diagram shows a schematic of an electrically heated fluidized bed continuous graphitization system. Solid arrows represent the flow direction of the carrier gas in the reactor, while dashed arrows represent the flow direction of the solid medium within the system.

[0058] In specific implementation, the solid medium first enters the electrically heated fluidized bed reactor 02 through the first countercurrent cyclone separator 01 via the solid medium inlet 1. The carrier gas enters the second countercurrent cyclone separator 03 via the carrier gas inlet 10, mixing with the graphitization reaction raw material entering the second countercurrent cyclone separator 03 via the graphitization reaction raw material inlet 9. The graphitization reaction raw material, carried by the carrier gas, rises into the electrically heated fluidized bed reactor 02. That is, the flow direction of the graphitization reaction raw material and the carrier gas in the system is opposite to the flow direction of the solid medium in the system. The solid medium enters the electrically heated fluidized bed reactor 02 from top to bottom via the first countercurrent cyclone separator 01, while the graphitization reaction raw material and the carrier gas enter the electrically heated fluidized bed reactor 02 from bottom to top via the second countercurrent cyclone separator 03. It should be noted that before the graphitization reaction raw material rises into the electrically heated fluidized bed reactor 02 under the carry of the carrier gas, the temperature of the main reaction zone of the electrically heated fluidized bed reactor 02 is maintained at 2500~3500℃. In this scenario, the solid medium initially entering the electrically heated fluidized bed reactor 02 absorbs heat. As it descends to the second counter-current cyclone separator 03, its high temperature preheats the upward-flowing carrier gas and graphitization reaction raw materials, ensuring their temperature reaches 800-1800°C before entering the reactor 02. Further, the carrier gas carries the graphitization reaction raw materials into the reactor 02, where they deposit on the solid medium to form graphite products. The heated carrier gas continues to ascend to the first counter-current cyclone separator 01, where it engages in counter-current contact heat exchange with the continuously entering solid medium, maintaining a temperature of 900-1800°C before entering the reactor 02. The resulting graphite products then sink into the second counter-current cyclone separator 03, where they engage in counter-current contact heat exchange with the continuously entering carrier gas and graphitization reaction raw materials, preheating both the graphitization reaction raw materials and the carrier gas, directly utilizing sensible heat, and improving energy efficiency. Finally, the carrier gas exits the system from the carrier gas outlet 2 at the top of the first countercurrent cyclone separator 01, and enters the second countercurrent cyclone separator 03 again from the carrier gas inlet 10 through the circulation pipeline 3, so as to achieve recycling.

[0059] Compared to conventional methods that involve feeding solid media, carrier gas, and graphitization reaction raw materials into the graphitization furnace from the same direction, recovering sensible heat requires an additional heat exchange device outside the graphitization furnace, resulting in a cumbersome and complex design. Furthermore, the particle size of the graphitization reaction raw materials that can be processed cannot reach the micrometer level. The system provided by this invention changes the conventional design by connecting the first countercurrent cyclone separator 01, the electrically heated fluidized bed reactor 02, and the second countercurrent cyclone separator 03 in series to form a new continuous graphitization reactor. The first countercurrent cyclone separator 01 and the second countercurrent cyclone separator 03 can both control the feed and discharge, and directly utilize sensible heat during the feed and discharge process, eliminating the need for a recovery device. The device structure is simple and easy to promote.

[0060] In some embodiments, the solid-gas ratio of the carrier gas to the graphitization reaction raw materials is not less than 20 to ensure sufficient graphitization reaction raw materials during continuous graphitization.

[0061] It should also be noted that, in this document, the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor should they be construed as indicating or implying relative importance. Moreover, the term "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements, but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device.

[0062] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, as some steps can be performed in other orders or simultaneously according to the present invention. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and components involved are not necessarily essential to the present invention.

[0063] The above provides a detailed description of the electrically heated fluidized bed continuous graphitization method and reactor provided by the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An electrically heated fluidized bed continuous graphitization reactor, characterized in that, The reactor comprises a first countercurrent cyclone separator, an electrically heated fluidized bed reactor, and a second countercurrent cyclone separator, which are linearly connected from top to bottom. The top of the first countercurrent cyclone separator is provided with a solid medium inlet and a carrier gas outlet; The bottom of the second countercurrent cyclone separator is provided with a carrier gas inlet, a graphitization reaction raw material inlet, and a solid medium and finished product outlet.

2. The fluidized bed continuous graphitization reactor according to claim 1, characterized in that, The electrically heated fluidized bed reactor is equipped with at least two infrared temperature measuring devices and at least three backflush pressure measuring devices to measure the pressure, material level, dense phase density, and temperature parameters of the electrically heated fluidized bed reactor.

3. The fluidized bed continuous graphitization reactor according to claim 1, characterized in that, The electrically heated fluidized bed reactor is connected to the first countercurrent cyclone separator through a fluidized bed solid medium inlet and a fluidized bed carrier gas outlet. The electrically heated fluidized bed reactor is connected to the second countercurrent cyclone separator via the fluidized bed solid medium outlet and the fluidized bed carrier gas and raw material inlet.

4. The fluidized bed continuous graphitization reactor according to claim 3, characterized in that, A flow regulating valve is provided at the outlet of the fluidized bed solid medium. The fluidized bed height is controlled by adjusting the valve opening of the flow regulating valve. The flow regulating valve is made of graphite or carbon-carbon composite material.

5. The fluidized bed continuous graphitization reactor according to claim 1, characterized in that, The electrically heated fluidized bed reactor is equipped with at least one layer of gas distributor.

6. The fluidized bed continuous graphitization reactor according to claim 1, characterized in that, The electrically heated fluidized bed reactor consists of a three-layer furnace lining with a total thickness of 150-300 mm, including an inner layer of graphite or magnesia-carbon brick structure, a middle layer of carbon felt or diatomaceous earth brick structure, and an outer layer of carbon steel structure. The electrically heated fluidized bed reactor is equipped with graphite electrodes that extend radially directly into the reactor at different axial heights. The electrically heated fluidized bed reactor is equipped with a graphite Venturi backflush device to introduce carrier gas and prevent carbon powder from adhering to and conducting the graphite electrodes.

7. The fluidized bed continuous graphitization reactor according to claim 1, characterized in that, Both the first countercurrent cyclone separator and the second countercurrent cyclone separator are multi-stage countercurrent cyclone separators that are coaxially mounted. Both the first countercurrent cyclone separator and the second countercurrent cyclone separator are equipped with a cyclone separator insulation layer.

8. The fluidized bed continuous graphitization reactor according to claim 1, characterized in that, The top of the first countercurrent cyclone separator is equipped with a heat exchanger to ensure that the outlet temperature of the carrier gas is lower than the ignition point of the combustible material formed after the impurities in the graphitization reaction raw material are gasified.

9. A method for continuous graphitization in an electrically heated fluidized bed, characterized in that, The method is applicable to the reactor described in any one of claims 1-8, and the method includes: Argon gas is used as the carrier gas to carry the graphitization reaction raw materials into the electrically heated fluidized bed reactor via the second countercurrent cyclone separator; the solid medium enters the electrically heated fluidized bed reactor via the first countercurrent cyclone separator. In the electrically heated fluidized bed reactor, the graphitization reaction raw materials are deposited on the solid medium to form graphite products; The graphite product further descends and enters the second countercurrent cyclone separator, where it undergoes countercurrent contact heat exchange with the carrier gas and graphitization reaction raw materials before exiting the second countercurrent cyclone separator. The carrier gas rises further and enters the first countercurrent cyclone separator, where it undergoes countercurrent contact heat exchange with the graphite particles. It then exits the first countercurrent cyclone separator and is recycled and reused through a circulation pipeline.

10. The fluidized bed continuous graphitization method according to claim 9, characterized in that, The solid-gas ratio of the carrier gas to the graphitization reaction raw materials is not less than 20; The graphitization reaction raw material is A or B type micron-sized carbon black particles with an average particle size of 10μm~1mm; the solid medium is graphite particles. The temperature inside the electrically heated fluidized bed reactor is 2500~3500℃.

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