A system and method for preparing a gas-phase silicon-carbon negative electrode material

Abstract

The application discloses a kind of gas phase silicon-carbon negative electrode material preparation system and method, belong to silicon-carbon negative electrode material technical field.The preparation system disclosed in the application, by setting solid raw material supply device, fluidized bed reactor, gas deposition rotary furnace, product post-treatment device, heat recovery device and gas raw material supply system, solve the gas phase silicon-carbon negative electrode material preparation in gas deposition equipment production scale small, high production cost, technical engineering amplification gas deposition uniformity decline, filter frequent blockage and high temperature sealing implementation difficult and other technical problems.

Description

Technical Field

[0001] This invention belongs to the field of silicon-carbon anode material technology, specifically relating to a gas-phase silicon-carbon anode material preparation system and method. Background Technology

[0002] In recent years, with the increasing global demand for high-efficiency energy conversion and storage tools, the consumer demand for lithium batteries has grown rapidly. Silicon-based materials are the next generation of lithium battery anode materials, possessing advantages such as high energy density (4200mAh / g), long lifespan, and low cost, and are widely used in consumer electronics, power tools, and power batteries. However, silicon-based anode materials are still in the technological development stage. Technical problems such as poor material conductivity, electrode cracking due to volume expansion / contraction, and instability of the SEI film greatly limit the large-scale application of these materials.

[0003] Silicon-carbon anode materials are novel silicon-based anode materials formed by combining nano-silicon with carbon materials. Their unique silicon / carbon composite structure significantly improves conductivity and buffers volume expansion, greatly enhancing electrochemical performance. Currently, silicon-carbon anode materials are gradually replacing graphite anode materials, and their application in consumer and power batteries is expanding.

[0004] The main silicon-carbon anode material preparation technologies in the industry are mechanical ball milling and chemical vapor deposition (CVD). Silicon-carbon anode materials prepared by mechanical ball milling, also known as milled silicon-carbon, have a relatively mature process and require less equipment investment. However, the resulting nano-silicon particles are relatively large, easily introducing impurities and causing severe agglomeration, leading to poor cycle performance. Chemical vapor deposition (CVD) prepares silicon-carbon anode materials with a shorter process flow, fewer equipment requirements, and allows for precise control of the silicon-carbon anode material structure. The resulting products exhibit excellent performance in first-cycle efficiency, energy density, and cycle performance, and are expected to lead the future development of the silicon-based anode industry.

[0005] The preparation of silicon-carbon anode materials via vapor deposition (CVD) primarily utilizes porous carbon as a carrier, achieving in-situ composite silicon / carbon materials and carbon layer coating through a two-step CVD reaction process: silicon deposition and carbon coating. However, the solid phase in the CVD process consists of typical Class C particles, characterized by small particle size, low density, and easy agglomeration. The fluidization process exhibits significant channeling and large-scale dead zones, severely impacting the quality of CVD deposition and product performance. Currently, CVD silicon-carbon anode materials are mostly prepared using stirred-assisted fluidized beds. Paddle shearing suppresses bubble growth and channeling in the bed, thereby improving fluidization quality and enhancing the uniformity of CVD deposition. However, existing technologies and equipment have limited batch production capacity. Large-scale production using multiple parallel units suffers from product consistency issues and high costs. Furthermore, the engineering scale-up of existing technologies and equipment faces challenges such as decreased CVD deposition uniformity, frequent filter clogging, and difficulties in achieving high-temperature sealing. Summary of the Invention

[0006] The purpose of this invention is to provide a system and method for preparing gas-phase silicon-carbon anode materials, which solves the technical problems of high energy consumption, low production efficiency, poor batch stability, and difficulty in achieving large-scale mass production in existing preparation processes.

[0007] To achieve the above objectives, the present invention employs the following technical solution:

[0008] This invention discloses a gas-phase silicon-carbon anode material preparation system, comprising: a solid raw material supply device, a fluidized bed reactor, a vapor deposition rotary furnace, a product post-processing device, a heat recovery and utilization device, and a gaseous raw material supply system; the solid raw material supply device, the fluidized bed reactor, the vapor deposition rotary furnace, and the product post-processing device are connected sequentially via pipelines; the gaseous raw material supply system is connected to the fluidized bed reactor, the vapor deposition rotary furnace, and the product post-processing device via pipelines; the tops of the solid raw material supply device, the fluidized bed reactor, the vapor deposition rotary furnace, and the product post-processing device are connected to the heat recovery and utilization device via pipelines.

[0009] Furthermore, the solid raw material supply device includes a weighing device and a preheating chamber connected in sequence; the weighing device is connected to the top of the preheating chamber via a pipeline; the outlet of the preheating chamber is connected to the inlet of the fluidized bed reactor.

[0010] The preheating chamber is equipped with a heating device.

[0011] Furthermore, the fluidized bed reactor comprises, from bottom to top, a gas chamber, a reaction section, a cooling section, and a separation section connected in sequence; the gas feedstock supply system includes nitrogen, silicon source gas, and carbon source gas.

[0012] Furthermore, the fluidized bed reactor includes a lower head, a nozzle, and a gas distributor; the lower head is located at the bottom of the fluidized bed reactor, and the nozzle is located above the lower head; the gas distributor is connected to the nozzle; a cavity is formed between the lower head and the gas distributor to form a gas chamber;

[0013] It also includes a variable diameter cone, a process gas preheating tube bundle, a cooling tube bundle, a first cylinder and a second cylinder; the upper end of the variable diameter cone is connected to the lower end of the first cylinder, and the lower end is connected to the upper end of the second cylinder; the process gas preheating tube bundle and the cooling tube bundle are arranged sequentially from bottom to top inside the first cylinder;

[0014] It also includes a central conduit, a flow guide block, and a heating system; the central conduit is located at the upper end of the gas distributor and has a gap between it and the nozzle; the heating system is located on the outside of the second cylinder, and a gap is left between the central conduit and the second cylinder; the flow guide block is located between the variable diameter cone and the central conduit;

[0015] It also includes a built-in filter and a top flat cover; the top flat cover is located at the upper end of the first cylinder; the components of the built-in filter pass through the top flat cover and are located inside the upper end of the first cylinder;

[0016] There is a space between the gas distributor and the variable-diameter cone, which forms a reaction section; there is a space between the variable-diameter cone and the built-in filter, which forms a cooling section; there is a space between the cooling tube bundle and the top flat cover, which forms a separation section.

[0017] Furthermore, the gas distributor has a conical structure, including a perforated plate and a wire mesh; the perforated plate and the wire mesh are attached to each other, and the wire mesh is disposed on the lower side wall surface of the perforated plate.

[0018] Furthermore, the sidewall of the fluidized bed reactor is also provided with a jet gas inlet, an auxiliary fluidizing gas inlet, a solid feed inlet, a solid discharge outlet, a process gas preheating inlet, a process gas preheating outlet, a fluidized bed cooling medium inlet, a fluidized bed cooling medium outlet, and a tail gas outlet; the jet gas inlet and the auxiliary fluidizing gas inlet are located on the sidewall of the gas chamber; the solid feed inlet and the solid discharge outlet are located on both sides of the variable diameter cone; the process gas preheating inlet and the process gas preheating outlet are located on the outer sidewall of the first cylinder and are respectively connected to both ends of the internal process gas preheating tube bundle; the fluidized bed cooling medium inlet and the fluidized bed cooling medium outlet are located on the outer sidewall of the first cylinder and are respectively connected to both ends of the internal cooling tube bundle; the tail gas outlet is connected to an internal filter;

[0019] The solid feed inlet is connected to the discharge outlet of the preheating chamber; the solid discharge outlet is connected to the feed inlet of the vapor deposition rotary furnace; the jet gas inlet, auxiliary fluidizing gas inlet, process gas preheating inlet, and process gas preheating outlet are respectively connected to the gas raw material supply system;

[0020] The fluidized bed cooling medium inlet is connected to the cooling medium; the exhaust gas outlet is connected to the heat recovery and utilization device.

[0021] Furthermore, the product post-processing device includes a product cooler, a screening device, and a demagnetizer connected in sequence; a first screw conveyor is provided between the vapor deposition rotary furnace and the product cooler; and a second screw conveyor is provided between the product cooler and the screening device.

[0022] The product cooler includes a conical head, a cylindrical body, a flat cover, a pipe filter, a stirrer, a cooling jacket, and a cooler gas distributor; the flat cover is located at the upper port of the cylindrical body; the conical head is located at the lower port of the cylindrical body; the stirrer assembly extends into the interior of the cylindrical body through the flat cover; the cooling jacket covers the outer surface of the conical head and the cylindrical body; the cooler gas distributor is located inside the lower end of the cylindrical body.

[0023] The product cooler cylinder is also provided with a cooler inlet, a cooler outlet, a cooler nitrogen inlet, a cooler exhaust outlet, a cooler cooling medium inlet, and a cooler cooling medium outlet.

[0024] The cooler inlet is connected to the outlet of the vapor deposition rotary furnace via a pipeline; the cooler outlet is connected to the second screw conveyor; the cooler nitrogen inlet is externally connected to a nitrogen pipeline and internally connected to a cooler gas distributor; the cooler cooling medium inlet is connected to a cooling medium; the cooler exhaust outlet is connected to a heat recovery and utilization device via a pipeline; and the pipe filter is installed in the cooler exhaust outlet.

[0025] Furthermore, the heat recovery and utilization device includes a first heat exchanger, a second heat exchanger, an exhaust gas cooler, a condensate tank, a first filter, and a second filter; the exhaust gas outlet is sequentially connected to the first heat exchanger, the second heat exchanger, the exhaust gas cooler, the condensate tank, the first filter, and the second filter.

[0026] Furthermore, it also includes a first heater, a second heater, a third heater, a fourth heater, a first mixer, and a second mixer;

[0027] The nitrogen gas is divided into three streams. The first stream of nitrogen gas is connected to the preheating chamber through a pipeline. The second stream of nitrogen gas is connected to the product cooler through a pipeline. The third stream of nitrogen gas is connected to the first heat exchanger and the third heater in sequence through pipelines, and then connected to the inlet of the first mixer and the second mixer respectively.

[0028] The silicon source gas is connected to the process gas preheating inlet via a pipeline, and then connected to the first heater via the process gas preheating outlet pipeline, and finally connected to the inlet of the first mixer; when the fluidized bed reactor performs the silicon deposition reaction, the silicon source gas and nitrogen are mixed in the first mixer and then enter the fluidized bed reactor.

[0029] The carbon source gas is divided into two streams. The first stream of carbon source gas is connected to the process gas preheating inlet via a pipeline, then connected to the second heater via the process gas preheating outlet pipeline, and finally connected to the inlet of the first mixer. When the carbon coating reaction is carried out in the fluidized bed reactor, the carbon source gas and nitrogen are mixed in the first mixer and then enter the fluidized bed reactor. The second stream of carbon source gas is connected to the second heat exchanger and the fourth heater in sequence via pipelines, and then connected to the inlet of the second mixer. When the deep carbon coating reaction is carried out in the vapor deposition rotary furnace, the carbon source gas and nitrogen are mixed in the second mixer and then enter the vapor deposition rotary furnace.

[0030] The outlet of the first mixer is divided into two paths, which are connected to the jet gas inlet and the auxiliary fluidizing gas inlet, respectively.

[0031] The exhaust gas outlets of the preheating chamber, the vapor deposition rotary furnace, and the product cooler are collected through pipelines and then flow into the exhaust gas cooler via the first and second heat exchangers.

[0032] This invention also discloses a method for using the above-mentioned gas-phase silicon-carbon anode material preparation system, comprising the following steps: First, nitrogen gas from the gaseous raw material supply system is introduced into the solid raw material supply device, and the solid raw material is transported into a fluidized bed reactor; second, a process gas composed of silicon source gas and nitrogen gas is introduced into the fluidized bed reactor to react with the solid raw material in a silicon deposition reaction to obtain silicon-carbon intermediate I; subsequently, the silicon source gas is stopped, and a process gas composed of carbon source gas and nitrogen gas is introduced into the fluidized bed reactor to react with silicon-carbon intermediate I in a carbon coating reaction to obtain silicon-carbon intermediate II; next, nitrogen gas is introduced into the fluidized bed reactor to transport silicon-carbon intermediate II to a gas-phase deposition rotary kiln, and a process gas composed of carbon source gas and nitrogen gas is introduced again to conduct a deep carbon coating reaction to obtain a silicon-carbon composite material; subsequently, the obtained silicon-carbon composite material is transported to a product post-processing device for processing to obtain a gas-phase silicon-carbon anode material;

[0033] Waste heat generated during the reaction process from the solid raw material supply device, fluidized bed reactor, vapor deposition rotary furnace, and product post-processing device is recovered through a heat recovery and utilization device.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] This invention discloses a system for preparing gas-phase silicon-carbon anode materials. By incorporating a solid raw material supply device, a fluidized bed reactor, a vapor deposition rotary furnace, a product post-processing device, a heat recovery and utilization device, and a gaseous raw material supply system, it is suitable for performing vapor-phase silicon deposition and vapor-phase carbon coating operations using 5-15 μm porous carbon as a carrier. It enables stable internal circulation fluidization of the particulate phase and waste heat recovery and utilization during the preparation of silicon-carbon anode materials via vapor deposition. The operation does not require frequent operation of high-temperature equipment such as the fluidized bed reactor and CVD rotary furnace. Significantly increasing and decreasing the temperature can reduce overall energy consumption and improve production efficiency, which is beneficial for reducing production costs and shortening the production cycle in the mass production of vapor-phase silicon-carbon anode materials. The process system has the advantages of a tight flow, high production efficiency, low overall energy consumption, and low operating costs, which can meet the requirements of large-scale and controllable preparation of high-quality vapor-phase silicon-carbon anode materials. It solves the technical problems in the preparation of vapor-phase silicon-carbon anode materials, such as the small production scale and high production cost of vapor deposition equipment, the decrease in vapor deposition uniformity after the technology is scaled up, frequent filter clogging, and the difficulty in achieving high-temperature sealing.

[0036] Furthermore, the fluidized bed reactor, from bottom to top, comprises a gas chamber, a reaction section, a cooling section, and a separation section connected sequentially. Relying solely on pneumatic action and fixed internal components, it achieves stable internal circulation and jet fluidization of the particulate phase, creating favorable gas-solid contact reaction conditions for effective gas-phase deposition. It boasts advantages such as minimal scale-up effect, good batch-to-batch product quality stability, and ease of large-scale equipment development, meeting the needs of large-scale preparation technology of gas-phase silicon-carbon anode materials. The cooling tube bundles within the reactor can recover waste heat from the reaction tail gas while reducing the tail gas temperature, preventing unreacted process gases from pyrolyzing and depositing on the surface of the built-in filter, effectively solving the production problem of frequent clogging of the built-in filter.

[0037] Furthermore, the product cooler employs a simultaneous cooling operation of direct nitrogen contact and indirect heat exchange between the cooling medium and the wall, which can effectively prevent the product powder from agglomerating and significantly improve the cooling efficiency of the product powder, saving production time. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the overall structure of the vapor-phase silicon-carbon anode material preparation system of the present invention;

[0039] Figure 2 This is a schematic diagram of the structure of the fluidized bed reactor of the present invention;

[0040] Figure 3 This is a schematic diagram of the gas distributor of the present invention;

[0041] Figure 4 This is a schematic diagram of the structure of the cooler for the product of this invention;

[0042] Wherein: 1-Weighing device; 2-Preheating chamber; 3-Fluidized bed reactor; 301-Lower head; 302-Nozzle; 303-Heating system; 304-Central conduit; 305-Guide block; 306-Variable diameter cone; 307-Process gas preheating tube bundle; 308-Cooling tube bundle; 309-Built-in filter; 310-Top flat cover; 311-First cylinder; 312-Second cylinder; 313-Gas distributor; 3131-Orifice plate; 3132 - Wire mesh; N1-Jet gas inlet; N2-Auxiliary fluidizing gas inlet; N3-Solid feed inlet; N4-Solid discharge outlet; N5-Process gas preheating inlet; N6-Process gas preheating outlet; N7-Fluidized bed cooling medium inlet; N8-Fluidized bed cooling medium outlet; N9-Tail gas outlet; T1-Bed temperature measuring port I; T2-Bed side temperature measuring port II; T3-Top temperature measuring port; P1-Bed pressure measuring port; P2-Top pressure measuring port; 4-First heat exchanger; 5- 6-First heater; 7-Second heater; 8-Third heater; 9-First mixer; 10-Tail gas cooler; 11-Condensate tank; 12-Second heat exchanger; 13-Second mixer; 14-Vacuum deposition rotary furnace; 15-First screw conveyor; 16-Product cooler; 1601-Conical head; 1602-Cylinder; 1603-Flat cover; 1604-Port filter; 1605-Agitator; 1606-Cooling jacket Set; 1607-Cooler gas distributor; N10-Cooler inlet; N11-Cooler outlet; N12-Cooler nitrogen inlet; N13-Cooler exhaust outlet; N14-Cooler cooling medium inlet; N15-Cooler cooling medium outlet; T-Cooler powder temperature measuring port; P-Cooler gas phase pressure measuring port; 17-Second screw conveyor; 18-Screwing device; 19-Demagnetizer; 20-First filter; 21-Second filter. Detailed Implementation

[0043] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0044] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0045] The present invention will now be described in further detail with reference to the accompanying drawings:

[0046] This invention discloses a system for preparing gas-phase silicon-carbon anode materials, comprising: a solid raw material supply device, a fluidized bed reactor 3, a vapor deposition rotary furnace 14, a product post-processing device, a heat recovery and utilization device, and a gaseous raw material supply system; the solid raw material supply device, fluidized bed reactor 3, vapor deposition rotary furnace 14, and product post-processing device are sequentially connected by pipelines; the gaseous raw material supply system is connected to the fluidized bed reactor 3 and vapor deposition rotary furnace 14 respectively by pipelines; the tops of the solid raw material supply device, fluidized bed reactor 3, vapor deposition rotary furnace 14, and product post-processing device are connected to the heat recovery and utilization device by pipelines; through modern heating technology, internal circulation jet bed technology, heat recovery technology, and process system coupling, a complete set of technologies and equipment for the large-scale preparation of gas-phase silicon-carbon anode materials is provided, which has the characteristics of small engineering scale-up effect, easy equipment scaling, low overall energy consumption, good product quality, and high production efficiency, and is suitable for the large-scale preparation of high-quality, low-cost gas-phase silicon-carbon anode materials.

[0047] Specifically, such as Figures 1-4 As shown, the solid raw material supply device includes a weighing device 1 and a preheating chamber 2 connected in sequence; the gaseous raw material supply system includes nitrogen, silicon source gas, and carbon source gas; the weighing device 1 is connected to the top of the preheating chamber 2 through a pipeline; the outlet of the preheating chamber 2 is connected to the inlet of the fluidized bed reactor 3; the fluidized bed reactor 3 includes, from bottom to top, a gas chamber, a reaction section, a cooling section, and a separation section connected in sequence; the product post-processing device includes a product cooler 16, a screening device 18, and a demagnetizer 19 connected in sequence; the heat recovery and utilization device includes a tail gas cooler 9, a condensate tank 10, a first heat exchanger 4, a second heat exchanger 11, a first filter 20, and a second filter 21.

[0048] Preferably, the weighing device 1 can be a metering hopper with a weighing sensor or a screw metering feeder, with a screw metering feeder being preferred; the preheating hopper 2 is equipped with a heating device, which can be one of a resistance heater, a microwave heater, or an inductive heater, with a microwave heater being preferred.

[0049] Preferably, the fluidized bed reactor 3 includes a lower head 301, a nozzle 302, a gas distributor 313, a central conduit 304, a guide block 305, a heating system 303, a variable diameter cone 306, a process gas preheating tube bundle 307, a cooling tube bundle 308, a first cylinder 311, a second cylinder 312, an internal filter 309, and a top flat cover 310; the lower head 301 is located at the bottom of the fluidized bed reactor 3, and the nozzle 302 is located at the upper end of the lower head 301; the gas distributor 313 is connected to the nozzle 302; the central conduit 304 is located at the upper end of the gas distributor 313, and a gap is left between it and the nozzle 302; the heating system 303 is located outside the second cylinder 312; the central conduit 304 and the second cylinder 312 are connected. A gap is left between the two; the upper end of the variable diameter cone 306 is connected to the lower end of the first cylinder 311, and the lower end is connected to the upper end of the second cylinder 312; the process gas preheating tube bundle 307 and the cooling tube bundle 308 are arranged sequentially from bottom to top inside the first cylinder 311; the top flat cover 310 covers the upper end of the first cylinder 311; the built-in filter 309 assembly passes through the top flat cover 310 and is arranged inside the upper end of the first cylinder 311; wherein, the gas chamber is the space between the lower end cap 301 and the gas distributor 313, the reaction section is the space between the gas distributor 313 and the variable diameter cone 306, the cooling section is the space between the variable diameter cone 306 and the built-in filter 309, and the separation section is the space between the cooling tube bundle 308 and the top flat cover 310.

[0050] Preferably, the sidewall of the fluidized bed reactor 3 is further provided with a jet gas inlet N1, an auxiliary fluidizing gas inlet N2, a solid feed inlet N3, a solid discharge outlet N4, a process gas preheating inlet N5, a process gas preheating outlet N6, a fluidized bed cooling medium inlet N7, a fluidized bed cooling medium outlet N8, and a tail gas outlet N9; the jet gas inlet N1 and the auxiliary fluidizing gas inlet N2 are located on the sidewall of the gas chamber; the solid feed inlet N3 and the solid discharge outlet N4 are located on both sides of the variable diameter cone 306; the process gas preheating inlet N5 and the process gas preheating outlet N6 are located on the outer sidewall of the first cylinder 311, and are respectively connected to both ends of the internal process gas preheating tube bundle 307. The fluidized bed cooling medium inlet N7 and fluidized bed cooling medium outlet N8 are located on the outer side wall of the first cylinder 311 and are respectively connected to both ends of the internal cooling tube bundle 308; the tail gas outlet N9 is connected to the filter 309; the solid feed inlet N3 is connected to the discharge port of the preheating chamber 2; the solid discharge port N4 is connected to the feed inlet of the vapor deposition rotary furnace 14; the jet gas inlet N1, auxiliary fluidizing gas inlet N2, process gas preheating inlet N5, and process gas preheating outlet N6 are respectively connected to the gas raw material supply system; the fluidized bed cooling medium inlet N7 is connected to the cooling medium; and the tail gas outlet N9 is connected to the heat recovery and utilization device.

[0051] The fluidized bed reactor 3 described above consists of four parts from bottom to top: a gas chamber, a reaction section, a cooling section, and a separation section. It forms an internal circulating, jet-fluidized system for the particles within the reactor, completing the pyrolysis and deposition reaction of the process gas. Specific structural features include:

[0052] The gas chamber is the space between the lower head 301 and the gas distributor 313, externally equipped with a jet gas inlet N1 and an auxiliary fluidizing gas inlet N2 to achieve zoned feeding and distribution of gas. The reaction section is the space between the gas distributor 313 and the variable diameter section 306. The reaction section is externally equipped with a heating system 303 and internally equipped with the gas distributor 313, nozzle 302, central guide tube 304, and guide block 305. The gas distributor 313 has a conical structure, with a semi-cone angle α less than the complementary angle of the particle phase repose angle. Specifically, it is composed of an orifice plate 3131 and a wire mesh 3132 to achieve auxiliary fluidizing gas distribution. The perforated plate 3131 is preferably a stainless steel perforated plate with a hole diameter of 3-6 mm, and the hole center distance is 1.25 times the hole diameter. The hole distribution can be any one of equilateral triangle, corner triangle, square or corner square, preferably equilateral triangle; the wire mesh 3132 is a 400-800 mesh stainless steel wire mesh, which is welded to the bottom of the perforated plate 3131; the nozzle 302 is connected to the small end of the cone of the gas distributor 313, and the throat diameter is d1. In order to achieve the jet fluidization of the particle phase, the value of d1 needs to ensure that the jet gas velocity is greater than the minimum jet velocity of the particles. The central conduit 304 is located at the center of the second cylinder 312, with a diameter of d2. The distance from its lower end to the nozzle 302 is H1, where d2 ≥ d1 + (0.2~0.5)*H1. The guide block 305 is an inverted isosceles triangle structure, with its centerline aligned with the axis of the central conduit 304. Its base length is L, where L ≥ (1.2~1.8)*d2. Its apex angle is β, where β = 90~120°. The distance from the lower apex to the upper end of the central conduit 304 is H2, where H2 ≥ (1.5~2)*d2. Furthermore, the reaction section is equipped with bed temperature measuring ports T1 and T2 from bottom to top. T1 and T2 are located along... There can be 2 to 3 measuring points along the axis. A bed pressure measuring port P1 is set in the middle of the reaction section. The pressure measuring port pressure tap has a backflushing function. The cooling section is the space between the variable diameter cone 306 and the built-in filter 309. It contains a process gas preheating tube bundle 307 and a cooling tube bundle 308 to achieve effective cooling of the gas phase deposition reaction tail gas. The target temperature is 20 to 50°C below the process gas pyrolysis temperature. This avoids pyrolysis deposition of unreacted process gas on the surface of the built-in filter and prevents blockage of the filter element pores. In addition, a solid feed port N3 and a solid discharge port N4 are set in the middle of the variable diameter cone of the cooling section, which are connected to the pipeline for nitrogen pressurization of materials.

[0053] The separation section is the space between the cooling tube bundle 308 and the top flat cover 310, and has a built-in filter 309 to achieve gas-solid separation. The filter element of the built-in filter 309 is made of high-temperature resistant material and is equipped with a pulse backflushing function. The filter element can be either a metal sintered filter element or a ceramic filter element, preferably a metal sintered filter element made of 310S material. In addition, the upper part of the separation section is provided with a top temperature measuring port T3 and a top pressure measuring port P2 to realize the detection of the temperature and pressure of the exhaust gas of the separation section.

[0054] like Figure 3As shown, more specifically, the gas distributor 313 has a conical structure, including a perforated plate 3131 and a wire mesh 3132; the perforated plate 3131 and the wire mesh 3132 are attached to each other, and the wire mesh 3132 is disposed on the outer wall surface of the perforated plate 3131.

[0055] like Figure 4 As shown, the product cooler 16 includes a conical head 1601, a cylinder 1602, a flat cover 1603, a pipe filter 1604, a stirrer 1605, a cooling jacket 1606, and a cooler gas distributor 1607. The flat cover 1603 is located at the upper port of the cylinder 1602; the conical head 1601 is located at the lower port of the cylinder 1602; the stirrer 1605 extends through the flat cover 1603 into the interior of the cylinder 1602; the cooling jacket 1606 covers the outer surfaces of the conical head 1601 and the cylinder 1602; and the cooler gas distributor 1607 is located inside the lower end of the cylinder 1602.

[0056] The product cooler 16 is further provided with a cooler inlet N10, a cooler outlet N11, a cooler nitrogen inlet N12, a cooler exhaust outlet N13, a cooler cooling medium inlet N14, and a cooler cooling medium outlet N15 on its cylindrical body 1602. The cooler inlet N10 is connected to the outlet of the vapor deposition rotary furnace 14 via a pipeline. The cooler outlet N11 is connected to the second screw conveyor 17. The cooler nitrogen inlet N12 is externally connected to a nitrogen pipeline and internally connected to a cooler gas distributor 1607. The cooler cooling medium inlet N14 is connected to the cooling medium. The cooler exhaust outlet N13 is sequentially connected to a heat recovery and utilization device via a pipeline. The pipe filter 1604 is installed in the cooler exhaust outlet N13.

[0057] Preferably, the product cooler 16 has a conical bottom and flat cover vertical structure, with an internal agitator 1605, an external cooling jacket 1606, and a cooler gas distributor 1607 at the bottom. The agitator 1605 can be any one or a combination of frame agitators, anchor agitators, and ribbon agitators, preferably ribbon agitators. The cooling jacket 1606 can be an integral jacket, a half-pipe jacket, or a honeycomb jacket, preferably an integral jacket. The cooler gas distributor 1607 can be an annular perforated pipe or an annular porous pipe, preferably an annular porous pipe made of ceramic or powder metallurgy. In addition, the product cooler 16 is provided with a cooler inlet N10 and a cooler inlet outlet N11 to realize powder feeding and discharging. The cooler exhaust outlet N13 is provided with a pipe filter 1604 to realize the filtration and discharge of cooling nitrogen. The cooler gas phase pressure measuring port P and the cooler powder temperature measuring port T realize the detection of the material layer temperature and the gas phase pressure of the product cooler 16, respectively.

[0058] The above system is used in the following steps:

[0059] Step 1: Use nitrogen to purge the closed system after the preheating chamber 2 in the system. Stop purging when the oxygen content of the purging tail gas is below 10-20 PPM. During this period, preheat the fluidized bed reactor 3 and the vapor deposition rotary kiln 14 at a preheating temperature of 400-750℃.

[0060] Step 2: Add porous carbon to weighing device 1, and after measuring the specified weight of porous carbon, add it in batches to preheating chamber 2;

[0061] Step 3: Nitrogen gas is introduced into the bottom of preheating chamber 2 to replace the atmosphere inside the chamber. After 10-20 minutes, the internal heating device of preheating chamber 2 is turned on to directly heat the porous carbon. The final temperature is 400-750℃. After the temperature reaches the standard, the oxygen content of the tail gas at the top of preheating chamber 2 is detected. When the oxygen content is below 10-20 PPM, the nitrogen gas at the bottom of the chamber is turned off and the nitrogen gas at the top of the chamber is turned on to pressurize the preheated porous carbon to the fluidized bed reactor 3.

[0062] Step 4: Turn on the silicon source gas. The silicon source gas is preheated to 300-350°C by passing through the process gas preheating tube bundle 307 and the first heater 5 in the fluidized bed reactor 3. Nitrogen gas is preheated to 300-350°C by passing through the first heat exchanger 4 and the third heater 7 in sequence. After the preheated silicon source gas and nitrogen gas are fully mixed in the first mixer 8, they are fed into the fluidized bed reactor 3 through two channels: the jet gas inlet N1 and the auxiliary fluidizing gas inlet N2. This achieves internal circulation jet fluidization of the particles. During the process, the fluidized bed reactor 3 maintains a micro-positive pressure of 1-50 kPaG and a reaction temperature of 400-650°C to achieve gas-phase pyrolysis deposition of the silicon source. After 5-20 hours, the silicon deposition reaction ends, and silicon-carbon intermediate I is obtained.

[0063] Step 5: Turn off the silicon source gas and turn on the carbon source gas. The carbon source gas passes through the process gas preheating tube bundle 307 and the second heater 6 in the fluidized bed reactor 3 in sequence and is preheated to 250-300°C. The nitrogen gas passes through the first heat exchanger 4 and the third heater 7 in sequence and is preheated to 250-300°C. After the preheated carbon source gas and nitrogen gas are fully mixed in the first mixer 8, they are fed into the fluidized bed reactor 3 through two channels: the jet gas inlet N1 and the auxiliary fluidizing gas inlet N2. This achieves internal circulation jet fluidization of the particles. During the process, the fluidized bed reactor 3 maintains a micro-positive pressure of 1-50 kPaG and a reaction temperature of 400-700°C to achieve gas-phase pyrolysis deposition of the carbon source. After 1-10 hours, the carbon coating reaction ends and silicon-carbon intermediate II is obtained.

[0064] Step 6: Using nitrogen gas, silicon-carbon intermediate II is pressurized from fluidized bed reactor 3 to vapor phase deposition rotary furnace 14. The carbon source gas is preheated to 250-300℃ by passing through the second heat exchanger 11 and the fourth heater 12 in sequence; the nitrogen gas is preheated to 250-300℃ by passing through the first heat exchanger 4 and the third heater 7 in sequence. The preheated carbon source gas and nitrogen gas are mixed evenly in the second mixer 13 and then introduced into vapor phase deposition rotary furnace 14. During the process, vapor phase deposition rotary furnace 14 is maintained at a micro-positive pressure of 1-50 kPaG and a temperature of 450-700℃ to achieve vapor phase pyrolysis deposition of carbon source. After 5-20 hours, deep carbon coating is completed, and silicon-carbon composite material is obtained.

[0065] Step 7: The high-temperature silicon-carbon composite material is conveyed by the first screw conveyor 15 to the product cooler 16 for cooling, with a target temperature of 50-60℃;

[0066] Step 8: The cooled silicon-carbon composite material is conveyed to the screening device 18 through the second screw conveyor 17 to remove large particles of silicon-carbon anode material. Silicon-carbon composite material with unqualified particle size is recycled during the process.

[0067] Step 9: After the silicon-carbon composite material with qualified particle size is demagnetized by demagnetizer 19 to remove ferromagnetic substances, the silicon-carbon anode product is obtained. The final silicon-carbon anode material is then packaged.

[0068] In the above process, the high-temperature exhaust gas generated by the preheating chamber 2, fluidized bed reactor 3, vapor deposition rotary furnace 14 and product cooler 16 is collected through pipelines and then heat-recovered by the first heat exchanger 4 and the second heat exchanger 11 in sequence before entering the exhaust gas cooler 9 for deep cooling, with a target temperature of 50-60°C. Subsequently, the cold exhaust gas is deeply purified by the first filter 20 and the second filter 21 before entering the flare for incineration. The condensate generated in the exhaust gas cooler 9 during the process is periodically recovered by the condensate tank 10.

[0069] Specifically, the vapor-phase deposition reaction process in fluidized bed reactor 3 is as follows:

[0070] The process mixed gas enters the reactor under slightly positive pressure conditions through two streams. One stream, as a jet gas, enters the reactor through the jet gas inlet N1. Utilizing the "jet effect" of nozzle 302, it entrains porous carbon particles from the bottom and rises along the central conduit 304 in a conveyor bed state. After the gas and solid phases separate from the central conduit 304, a "fountain zone" is formed in the upper space of the second cylinder 312. Under the action of the guide block 305 and gravity, the particles fall back to the annular gap between the second cylinder 312 and the central conduit 304, and move to the bottom of the bed in a downward bed state, where they are again entrained by the jet gas, forming a state of internal particle circulation within the reactor. The other stream of process mixed gas, as an auxiliary fluidizing gas, enters the bottom of the reactor through the auxiliary fluidizing gas inlet N2. Under the action of the gas distributor 313, it enters the annular gap between the second cylinder 312 and the central conduit 304 evenly, making full contact with the particles in the downward bed, ensuring that the bed in the annular gap is loose and in a state of continuous downward movement. Under the special bed structure, the gas and solid two phases exhibit a stable internal circulation jet fluidization state in the fluidized bed reactor 3, and further, under the temperature conditions provided by the heating system 303, the process gas achieves gas phase pyrolysis deposition.

[0071] Preferably, the first screw conveyor 15 has a high-temperature resistant structure. In addition to traditional structural features, it is equipped with an external cooling jacket 1606 and the stirring shaft is a hollow structure with a cooling medium flowing inside.

[0072] Preferably, the product cooler 16 adopts a synchronous cooling method combining direct and indirect cooling. During operation, room temperature nitrogen gas is introduced through the nitrogen inlet N12 of the product cooler 16 and distributed by the cooler gas distributor 1607 to directly contact and cool the product powder. On the other hand, the cooling medium is introduced into the cooling jacket 1606 to achieve indirect cooling of the product powder through heat transfer through the metal wall. During the process, the agitator 1605 is continuously turned on to increase the heat transfer efficiency of the bed. The stirring speed is 1 to 80 rpm. After 2 to 4 hours of continuous cooling, the product powder can be cooled to 50 to 60°C.

[0073] The cooling medium in the process can be any of chilled water, circulating water, or heat transfer oil, with chilled water being the preferred choice.

[0074] Example 1

[0075] After nitrogen purging and preheating of the sealed system following preheating chamber 2, particles with a diameter of 10–15 μm and a bulk density of 0.5 g / cm³ were placed in the chamber. 3Porous carbon was added to weighing device 1, and 10 kg of porous carbon was added to preheating chamber 2. After nitrogen purging for 10 minutes, the oxygen content reached the standard. Subsequently, the heating device of preheating chamber 2 was started to heat the porous carbon to 560°C, and then nitrogen was used to pressurize the high-temperature porous carbon to the fluidized bed reactor. Next, silicon source gas was turned on, and both silicon source gas and nitrogen were preheated to 300°C and mixed. The mixture was then introduced into fluidized bed reactor 3 through two channels to form an internal circulation jet fluidization in the reaction space. During the process, the fluidized bed reactor 3 maintained the temperature of the reaction chamber through heating system 303. The silicon source gas pyrolysis deposition reaction was achieved at a temperature of 560℃. The reaction tail gas was cooled to 480℃ by the cooling tube bundle 308 in the fluidized bed reactor 3, then purified by the built-in filter 309 and discharged. Silicon deposition was completed after 12 hours, yielding silicon-carbon intermediate I. Next, the silicon source gas was shut off, and the carbon source gas was turned on. Both the carbon source gas and nitrogen were preheated to 250℃ and mixed, then introduced into the fluidized bed reactor 3 via two separate streams, forming an internal circulating jet fluidization within the reaction space. During this process, the fluidized bed reactor 3 maintained the reaction chamber temperature at 6℃ through the heating system 303. At 50℃, the carbon source gas undergoes pyrolysis deposition. The reaction tail gas is cooled to 400℃ via cooling tube bundle 308 in the fluidized bed reactor 3, then purified by the built-in filter 309 and discharged. After 4 hours, carbon coating is completed, yielding silicon-carbon intermediate II. Next, nitrogen gas is used to pressurize silicon-carbon intermediate II into the vapor deposition rotary furnace 14. Both the carbon source gas and nitrogen gas are preheated to 280℃ and mixed before being introduced into the vapor deposition rotary furnace 14. During this process, the vapor deposition rotary furnace 14 maintains the reaction chamber temperature at 700℃ using a heating device, achieving carbon source deposition. The gas pyrolysis deposition reaction was completed after 10 hours, resulting in a deep carbon coating and a silicon-carbon composite material. Next, the first screw conveyor 15 transported the 700°C high-temperature silicon-carbon material to the product cooler 16, where it was simultaneously cooled using ambient temperature nitrogen and chilled water. After 3 hours, the material temperature dropped to 60°C. Next, the cooled silicon-carbon composite material was conveyed via the second screw conveyor 17 to a screening device 18 and a demagnetizer 19 to remove large particles and ferromagnetic materials, resulting in a particle size of 12–18 μm and a bulk density of 0.95 g / cm³. 3 The silicon-carbon anode products are packaged and shipped out. The high-temperature exhaust gas generated during system operation is sent to the flare system after heat recovery and dust removal purification. The condensate is recovered regularly, and silicon-carbon materials and dust removal powder with unqualified particle size are sent for recycling.

[0076] Example 2

[0077] After nitrogen purging and preheating of the sealed system following the preheating chamber 2, particles with a diameter of 8–12 μm and a bulk density of 0.4 g / cm³ were used. 3Porous carbon was added to weighing device 1, and 25 kg of porous carbon was added to preheating chamber 2. After nitrogen purging for 15 minutes, the oxygen content reached the standard. Subsequently, the heating device of preheating chamber 2 was started to heat the porous carbon to 600°C, and then nitrogen was used to pressurize the high-temperature porous carbon to fluidized bed reactor 3. Next, silicon source gas was turned on, and both silicon source gas and nitrogen were preheated to 320°C and mixed. The mixture was then introduced into fluidized bed reactor 3 through two channels to form an internal circulation jet fluidization in the reaction space. During the process, fluidized bed reactor 3 maintained the reaction chamber through heating system 303. The silicon source gas pyrolysis deposition reaction was carried out at a temperature of 600℃. The reaction tail gas was cooled to 450℃ by the cooling tube bundle 308 in the fluidized bed reactor 3, then purified by the built-in filter 309 and discharged. Silicon deposition was completed after 15 hours, yielding silicon-carbon intermediate I. Next, the silicon source gas was shut off, and the carbon source gas was turned on. Both the carbon source gas and nitrogen were preheated to 280℃ and mixed, then introduced into the fluidized bed reactor 3 via two separate streams, forming an internal circulating jet fluidization within the reaction space. During the process, the fluidized bed reactor 3 maintained the reaction chamber temperature at 600℃ through the heating system 303. At 700℃, the carbon source gas undergoes pyrolysis deposition. The reaction tail gas is cooled to 430℃ via cooling tube bundle 308 in the fluidized bed reactor 3, then purified by the built-in filter 309 and discharged. Carbon coating is completed after 6 hours, yielding silicon-carbon intermediate II. Next, nitrogen gas is used to pressurize silicon-carbon intermediate II into the vapor deposition rotary furnace 14. Both the carbon source gas and nitrogen are preheated to 300℃ and mixed before being introduced into the vapor deposition rotary furnace 14. During this process, the vapor deposition rotary furnace 14 maintains the reaction chamber temperature at 720℃ using a heating device, achieving carbon deposition. The source gas pyrolysis deposition reaction, after 15 hours, completes the deep carbon coating, yielding a silicon-carbon composite material. Next, the first screw conveyor 15 transports the high-temperature silicon-carbon material (720℃) to the product cooler 16, where it is simultaneously cooled using ambient temperature nitrogen and chilled water. After 2 hours, the material temperature drops to 80℃. Next, the cooled silicon-carbon composite material is conveyed via the second screw conveyor 17 to the screening device 18 and demagnetizer 19 to remove large particles and ferromagnetic materials, resulting in a particle size of 10–15 μm and a bulk density of 1.1 g / cm³. 3 The silicon-carbon anode products are manufactured and packaged. The high-temperature exhaust gas generated during system operation is sent to the flare system after heat recovery and dust removal purification. The condensate is recovered periodically, and silicon-carbon materials and dust powder with unqualified particle size are sent for recycling.

[0078] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A system for preparing gas-phase silicon-carbon anode materials, characterized in that, include: The system includes a solid raw material supply device, a fluidized bed reactor (3), a vapor deposition rotary furnace (14), a product post-processing device, a heat recovery and utilization device, and a gaseous raw material supply system. The solid raw material supply device, fluidized bed reactor (3), vapor deposition rotary furnace (14), and product post-processing device are connected in sequence via pipelines. The gaseous raw material supply system is connected to the fluidized bed reactor (3), vapor deposition rotary furnace (14), and product post-processing device via pipelines. The tops of the solid raw material supply device, fluidized bed reactor (3), vapor deposition rotary furnace (14), and product post-processing device are connected to the heat recovery and utilization device via pipelines. The solid raw material supply device includes a weighing device (1) and a preheating chamber (2) connected in sequence; the weighing device (1) is connected to the top of the preheating chamber (2) through a pipeline; the outlet of the preheating chamber (2) is connected to the inlet of the fluidized bed reactor (3); The preheating chamber (2) is equipped with a heating device; The fluidized bed reactor (3) comprises, from bottom to top, a gas chamber, a reaction section, a cooling section, and a separation section connected in sequence; the gas feedstock supply system includes nitrogen, silicon source gas, and carbon source gas; The fluidized bed reactor (3) includes a lower head (301), a nozzle (302), and a gas distributor (313); the lower head (301) is located at the bottom of the fluidized bed reactor (3), and the nozzle (302) is located above the lower head (301); the gas distributor (313) is connected to the nozzle (302); a cavity is formed between the lower head (301) and the gas distributor (313) to form a gas chamber; It also includes a variable-diameter cone (306), a process gas preheating tube bundle (307), a cooling tube bundle (308), a first cylinder (311), and a second cylinder (312); the upper end of the variable-diameter cone (306) is connected to the lower end of the first cylinder (311), and the lower end is connected to the upper end of the second cylinder (312); the process gas preheating tube bundle (307) and the cooling tube bundle (308) are arranged sequentially from bottom to top inside the first cylinder (311); It also includes a central conduit (304), a flow guide block (305), and a heating system (303); the central conduit (304) is located at the upper end of the gas distributor (313) and has a gap between it and the nozzle (302); the heating system (303) is located outside the second cylinder (312), and there is a gap between the central conduit (304) and the second cylinder (312); the flow guide block (305) is located between the variable diameter cone (306) and the central conduit (304); It also includes a built-in filter (309) and a top flat cover (310); the top flat cover (310) is located at the upper end of the first cylinder (311); the components of the built-in filter (309) pass through the top flat cover (310) and are located inside the upper end of the first cylinder (311); There is a space between the gas distributor (313) and the variable diameter cone (306), which forms a reaction section; there is a space between the variable diameter cone (306) and the built-in filter (309), which forms a cooling section; there is a space between the cooling tube bundle (308) and the top flat cover (310), which forms a separation section.

2. The gas-phase silicon-carbon anode material preparation system according to claim 1, characterized in that, The gas distributor (313) has a conical structure and includes a perforated plate (3131) and a wire mesh (3132); the perforated plate (3131) and the wire mesh (3132) are attached to each other, and the wire mesh (3132) is disposed on the lower side wall surface of the perforated plate (3131).

3. The gas-phase silicon-carbon anode material preparation system according to claim 1, characterized in that, The sidewall of the fluidized bed reactor (3) is also provided with a jet gas inlet (N1), an auxiliary fluidizing gas inlet (N2), a solid feed inlet (N3), a solid discharge outlet (N4), a process gas preheating inlet (N5), a process gas preheating outlet (N6), a fluidized bed cooling medium inlet (N7), a fluidized bed cooling medium outlet (N8), and a tail gas outlet (N9); the jet gas inlet (N1) and the auxiliary fluidizing gas inlet (N2) are located on the sidewall of the gas chamber; the solid feed inlet (N3) and the solid discharge outlet (N9) are located on the sidewall of the gas chamber. 4) The process gas preheating inlet (N5) and process gas preheating outlet (N6) are located on both sides of the variable diameter cone (306); the process gas preheating inlet (N5) and process gas preheating outlet (N6) are located on the outer side wall of the first cylinder (311) and are respectively connected to the two ends of the internal process gas preheating tube bundle (307); the fluidized bed cooling medium inlet (N7) and fluidized bed cooling medium outlet (N8) are located on the outer side wall of the first cylinder (311) and are respectively connected to the two ends of the internal cooling tube bundle (308); the exhaust gas outlet (N9) is connected to the built-in filter (309); The solid feed inlet (N3) is connected to the discharge outlet of the preheating chamber (2); the solid discharge outlet (N4) is connected to the feed inlet of the vapor deposition rotary furnace (14); the jet gas inlet (N1), the auxiliary fluidizing gas inlet (N2), the process gas preheating inlet (N5), and the process gas preheating outlet (N6) are respectively connected to the gas raw material supply system; The fluidized bed cooling medium inlet (N7) is connected to the cooling medium; the exhaust gas outlet (N9) is connected to the heat recovery and utilization device.

4. The gas-phase silicon-carbon anode material preparation system according to claim 3, characterized in that, The product post-processing device includes a product cooler (16), a screening device (18), and a demagnetizer (19) connected in sequence; a first screw conveyor (15) is provided between the vapor deposition rotary furnace (14) and the product cooler (16); a second screw conveyor (17) is provided between the product cooler (16) and the screening device (18). The product cooler (16) includes a conical head (1601), a cylinder (1602), a flat cover (1603), a pipe filter (1604), a stirrer (1605), a cooling jacket (1606), and a cooler gas distributor (1607); the flat cover (1603) is located at the upper port of the cylinder (1602); the conical head (1601) is located at the lower port of the cylinder (1602); the components of the stirrer (1605) extend into the cylinder (1602) through the flat cover (1603); the cooling jacket (1606) covers the outer surfaces of the conical head (1601) and the cylinder (1602); the cooler gas distributor (1607) is located inside the lower end of the cylinder (1602); The product cooler (16) is further provided with a cooler inlet (N10), a cooler outlet (N11), a cooler nitrogen inlet (N12), a cooler exhaust outlet (N13), a cooler cooling medium inlet (N14), and a cooler cooling medium outlet (N15) on its cylinder (1602). The cooler inlet (N10) is connected to the outlet of the vapor deposition rotary furnace (14) via a pipeline; the cooler outlet (N11) is connected to the second screw conveyor (17); the cooler nitrogen inlet (N12) is externally connected to a nitrogen pipeline and internally connected to the cooler gas distributor (1607); the cooler cooling medium inlet (N14) is connected to the cooling medium; the cooler exhaust outlet (N13) is connected to a heat recovery and utilization device via a pipeline; and the pipe filter (1604) is installed in the cooler exhaust outlet (N13).

5. The gas-phase silicon-carbon anode material preparation system according to claim 4, characterized in that, The heat recovery and utilization device includes a first heat exchanger (4), a second heat exchanger (11), a tail gas cooler (9), a condensate tank (10), a first filter (20), and a second filter (21); the tail gas outlet (N9) is connected in sequence to the first heat exchanger (4), the second heat exchanger (11), the tail gas cooler (9), the condensate tank (10), the first filter (20), and the second filter (21).

6. The gas-phase silicon-carbon anode material preparation system according to claim 4, characterized in that, It also includes a first heater (5), a second heater (6), a third heater (7), a fourth heater (12), a first mixer (8), and a second mixer (13); The nitrogen gas is divided into three streams. The first stream of nitrogen gas is connected to the preheating chamber (2) through a pipeline. The second stream of nitrogen gas is connected to the product cooler (16) through a pipeline. The third stream of nitrogen gas is connected to the first heat exchanger (4) and the third heater (7) in sequence through a pipeline, and then connected to the inlet of the first mixer (8) and the second mixer (13) respectively. The silicon source gas is connected to the process gas preheating inlet (N5) through a pipeline, and then connected to the first heater (5) through the process gas preheating outlet (N6) pipeline, and then connected to the inlet of the first mixer (8); when the fluidized bed reactor (3) carries out the silicon deposition reaction, the silicon source gas and nitrogen are mixed in the first mixer (8) and enter the fluidized bed reactor (3). The carbon source gas is divided into two streams. The first stream of carbon source gas is connected to the process gas preheating inlet (N5) through a pipeline, and then connected to the second heater (6) through the process gas preheating outlet (N6) pipeline. After that, it is connected to the inlet of the first mixer (8). When the fluidized bed reactor (3) is carrying out the carbon coating reaction, the carbon source gas and nitrogen are mixed in the first mixer (8) and enter the fluidized bed reactor (3). The second stream of carbon source gas is connected to the second heat exchanger (11) and the fourth heater (12) in sequence through a pipeline, and then connected to the inlet of the second mixer (13). When the vapor deposition rotary furnace (14) is carrying out the deep carbon coating reaction, the carbon source gas and nitrogen are mixed in the second mixer (13) and enter the vapor deposition rotary furnace (14). The outlet of the first mixer (8) is divided into two paths, which are connected to the jet gas inlet (N1) and the auxiliary fluidizing gas inlet (N2) respectively; The exhaust gas outlets of the preheating chamber (2), the vapor deposition rotary furnace (14), and the product cooler (16) are collected through pipelines and then flow into the exhaust gas cooler (9) through the first heat exchanger (4) and the second heat exchanger (11).

7. A method of using the gas-phase silicon-carbon anode material preparation system according to any one of claims 1 to 6, characterized in that, Includes the following steps: First, nitrogen from the gaseous raw material supply system is introduced into the solid raw material supply device, and the solid raw material is transported into the fluidized bed reactor (3). Second, process gas composed of silicon source gas and nitrogen is introduced into the fluidized bed reactor (3) to react with the solid raw material in a silicon deposition reaction to obtain silicon-carbon intermediate I. Then, the silicon source gas is stopped, and process gas composed of carbon source gas and nitrogen is introduced into the fluidized bed reactor (3) to react with silicon-carbon intermediate I in a carbon coating reaction to obtain silicon-carbon intermediate II. Next, nitrogen is introduced into the fluidized bed reactor (3) to transport silicon-carbon intermediate II to the vapor deposition rotary furnace (14), and process gas composed of carbon source gas and nitrogen is introduced again to carry out a deep carbon coating reaction to obtain silicon-carbon composite material. Then, the obtained silicon-carbon composite material is transported to the product post-processing device for processing to obtain vapor phase silicon-carbon anode material. The waste heat generated during the reaction process by the solid raw material supply device, fluidized bed reactor (3), vapor deposition rotary furnace (14) and product post-processing device is recovered by the heat recovery and utilization device.

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