Reactors and methods suitable for ultrafine particle vapor deposition

Abstract

This invention discloses a reactor and method suitable for ultrafine particle vapor deposition, relating to the fields of chemical engineering and materials preparation technology. The reactor includes a reactor body, a feeding mechanism, and a gas-solid feed pipe connecting the reactor body and the feeding mechanism. The reactor body has a reaction bed section, a conveying bed section, and a descending bed section connected in sequence. The diameter ratio of the reaction bed section to the conveying bed section is greater than 1. At least one gas-phase nozzle is provided on the descending bed section, and a control valve is connected to the end of the descending bed section. The control valve is connected to an outlet pipe and a circulation pipe connected to the feeding mechanism. Thus, by setting the reaction bed section and the conveying bed section with narrower diameters, the apparent gas velocity entering the conveying bed section is automatically adjusted, carrying the solid product out for conveying. Simultaneously, the gas-phase nozzle in the descending bed section provides conditions for the solid product to undergo secondary reactions as needed. The selective connection of the control valve enables the extraction or circulation of the solid product.

Description

Technical Field

[0001] This invention relates to the fields of chemical engineering and materials preparation technology, and in particular to a reactor and method suitable for ultrafine particle vapor deposition. Background Technology

[0002] Lithium-ion batteries have been widely used in recent years due to their high energy density and efficiency. Improving energy density is crucial for lithium batteries; for example, higher energy density leads to longer driving ranges for electric vehicles. However, traditional graphite-based anode materials, with their relatively low theoretical capacity, cannot meet the requirements for constructing high-energy-density battery systems. Among various anode materials, silicon, with its highest theoretical capacity, is considered the most promising candidate to replace traditional graphite anodes. However, its high volume expansion rate makes the electrodes prone to breakage, pulverization, and even detachment from the current collector during cycling, severely limiting its commercialization. Composite materials composed of graphite and a small amount of silicon have thus emerged. Graphite can buffer the volume changes of silicon and provide a highly conductive matrix, while silicon can increase capacity. For mass production, coating uniformity is one of the most difficult and critical indicators to achieve. Traditional chemical vapor deposition (CVD) techniques suffer from excessive reaction dead zones and insufficiently uniform fluid and temperature fields, severely limiting the achievement of uniform coating.

[0003] Gas-solid fluidized bed reactors are widely used as a practical technology for powder preparation, processing, and heterogeneous catalytic reactions due to their excellent flow properties and transport capabilities. In the basic flow pattern of gas-solid fluidization, particles are dispersed and suspended in a continuous gas phase during the transport bed stage, which is conducive to the gas-phase deposition reaction. At the same time, transport bed reactors have advantages such as large throughput and ease of continuous operation, making them an ideal reactor choice for ultrafine particle gas-phase deposition processes. Summary of the Invention

[0004] The purpose of this invention is to provide a reactor and method suitable for ultrafine particle vapor deposition, which solves the problems of low heat and mass transfer efficiency and many reaction dead zones in the prior art of chemical vapor deposition.

[0005] The above-mentioned objectives of the present invention can be achieved by the following technical solutions:

[0006] This invention provides a reactor suitable for ultrafine particle vapor deposition, comprising:

[0007] The reactor body has a reaction bed section, a conveying bed section, and a descending bed section connected in sequence. The diameter of the reaction bed section is larger than the diameter of the conveying bed section. A gas phase outlet is provided on the conveying bed section. An anti-backflow component is provided at the connection between the conveying bed section and the descending bed section. At least one set of gas phase feed holes is provided on the descending bed section. Each set of gas phase feed holes has at least one gas phase feed hole. A gas phase nozzle is connected to the gas phase feed hole. A control valve is connected to the end of the descending bed section. A circulation pipe and an outlet pipe are connected to the control valve.

[0008] A gas-solid feed pipe is provided with a particle inlet. The two ends of the gas-solid feed pipe are a gas phase inlet and a gas-solid outlet, respectively. The particle inlet is located between the gas phase inlet and the gas-solid outlet. The gas-solid outlet is connected to the reaction bed section.

[0009] The feeding mechanism is provided with a first feed inlet, a second feed inlet and a discharge outlet. The second feed inlet is located between the first feed inlet and the discharge outlet. The first feed inlet is connected to the hopper. The second feed inlet is connected to the circulation pipe. The discharge outlet is connected to the particle inlet of the gas-solid feed pipe.

[0010] When the solid-phase reaction time at the control valve is sufficient, the control valve connects the outlet pipe to the downward bed section;

[0011] When the solid-phase reaction time to the control valve is insufficient, the control valve connects the circulation pipe to the downward bed section.

[0012] In one specific embodiment, the diameter ratio of the reaction bed section to the transport bed section is 1.1 to 3.

[0013] In one specific embodiment, at least one diffusion distributor is provided in the reaction bed section, the diffusion distributor is connected to the gas-solid outlet of the gas-solid feed pipe, and the outlet end of the diffusion distributor has multiple outlets spaced apart.

[0014] In one specific embodiment, a loop distributor is also provided in the reaction bed section, and the loop distributor is located upstream of multiple outlets of the diffusion distributor along the solid phase transport direction in the reactor body.

[0015] In one specific embodiment, the angle between the gas injection direction of the gas phase nozzle and the solid phase conveying direction within the reactor body is 10° to 170°.

[0016] In one specific embodiment, the gas phase velocity at the outlet of the gas phase nozzle is 10 m / s to 80 m / s.

[0017] In one specific embodiment, the reaction bed section is provided with at least one packing internal component, and the cross-sectional profile of at least one packing internal component coincides with the inner wall of the reaction bed section along the solid phase transport direction within the reactor body.

[0018] In one specific embodiment, a gas-solid ultra-short rapid separation structure is formed downstream of the conveying bed section along the solid phase conveying direction within the reactor body, and the gas phase outlet is provided on the gas-solid ultra-short rapid separation structure.

[0019] In one specific embodiment, a gas-solid separation structure is formed downstream of the downward bed section along the solid phase transport direction within the reactor body, and the control valve is connected to the end of the gas-solid separation structure.

[0020] In one specific embodiment, along the solid phase conveying direction within the reactor body, multiple gas phase feed hole groups are provided on the downward bed section. Each of the gas phase feed hole groups has multiple gas phase feed holes, and the multiple gas phase feed holes are spaced apart along the circumferential direction of the downward bed section. Each gas phase feed hole is connected to a gas phase nozzle.

[0021] A method for ultrafine particle vapor deposition, the method being implemented using a reactor as described above for ultrafine particle vapor deposition, comprising the following steps:

[0022] The feeding mechanism is turned on to introduce ultrafine particles, and the gas phase supply of the gas-solid feed pipe is turned on to introduce reaction gas and fluidizing gas into the reaction bed section, so as to maintain the apparent gas velocity in the reaction bed section in a turbulent bed or fast bed state.

[0023] When the solid phase reaction time entering the downflow bed section is sufficient and no secondary reaction is required, the control valve connects the outlet pipe to the downflow bed section, allowing the solid phase to be drawn out from the outlet pipe. When the solid phase reaction time entering the downflow bed section is insufficient, or when the solid phase reaction time entering the downflow bed section is sufficient but a secondary reaction is required, the gas phase nozzle is opened to introduce reaction gas and fluidizing gas into the downflow bed section. When the solid phase reaction time reaching the control valve is sufficient, or when the solid phase reaching the control valve has completed the secondary reaction, the control valve connects the outlet pipe to the downflow bed section, allowing the solid phase to be drawn out from the outlet pipe. When the solid phase reaction time reaching the control valve is insufficient and a cyclic reaction is required, the control valve connects the circulation pipe to the downflow bed section, sending the solid phase back to the reaction bed section to continue the gas phase deposition reaction.

[0024] The features and advantages of this invention are:

[0025] 1. The reactor of the present invention, applicable to ultrafine particle vapor deposition, achieves automatic adjustment of the apparent gas velocity entering the conveying bed section by setting a narrow-diameter interconnected reaction bed section and a conveying bed section, thereby carrying out the solid product through the conveying process.

[0026] 2. The reactor of the present invention, applicable to ultrafine particle vapor deposition, provides conditions for the solid product to undergo secondary reaction as needed by setting a gas phase nozzle in the downward bed section, and simultaneously setting an anti-backflow component to prevent the gas phase in the downward bed section from flowing back into the conveying bed section, thereby affecting the conveying and separation of the gas-solid mixture in the conveying bed section.

[0027] 3. The reactor of the present invention, applicable to ultrafine particle vapor deposition, facilitates the return of solid products that do not meet the preset requirements to the reaction bed section for recycling reaction by setting up a circulation pipe selectively connected to the feeding mechanism.

[0028] 4. The reactor of the present invention, applicable to ultrafine particle vapor deposition, has the characteristics of simple structure and small footprint. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0030] Figure 1 This is a schematic diagram of the structure of the reactor without packing internals for ultrafine particle vapor deposition according to the present invention;

[0031] Figure 2 This is a schematic diagram of the internal components of the reactor containing packing material suitable for ultrafine particle vapor deposition according to the present invention.

[0032] Explanation of icon numbers:

[0033] 1. Reactor body; 11. Reaction bed section; 12. Conveying bed section; 120. Gas-solid ultra-short rapid separation structure; 121. Gas phase outlet; 13. Downward bed section; 130. Gas phase feed port group; 131. Gas phase feed port; 132. Gas-solid separation structure; 14. Diameter reduction structure; 15. Material leg;

[0034] 2. Backflow prevention components;

[0035] 3. Control valve;

[0036] 4. Circulation pipe;

[0037] 5. Outlet tube;

[0038] 6. Gas-solid feed pipe; 61. Particle inlet; 62. Gas phase inlet; 63. Gas-solid outlet;

[0039] 7. Feeding mechanism; 71. First feed inlet; 72. Second feed inlet; 73. Discharge outlet;

[0040] 8. Diffuser;

[0041] 9. Loop-type distributor;

[0042] 10. Packing internal components;

[0043] α, the angle between the gas injection direction of the gas phase nozzle and the solid phase transport direction in the reactor body; D1, the diameter of the reaction bed section; D2, the diameter of the transport bed section. Detailed Implementation

[0044] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] like Figure 1 and Figure 2 As shown, the present invention provides a reactor suitable for ultrafine particle vapor deposition, comprising:

[0046] The reactor body 1 has a reaction bed section 11, a conveying bed section 12 and a descending bed section 13 connected in sequence. The diameter of the reaction bed section 11 is larger than the diameter of the conveying bed section 12. A gas phase outlet 121 is provided on the conveying bed section 12. An anti-backflow component 2 is provided at the connection between the conveying bed section 12 and the descending bed section 13. At least one set of gas phase feed holes 130 is provided on the descending bed section 13. The at least one set of gas phase feed holes 130 has at least one gas phase feed hole 131. A gas phase nozzle is connected to the gas phase feed hole 131. A control valve 3 is connected to the end of the descending bed section 13. A circulation pipe 4 and an outlet pipe 5 are connected to the control valve 3.

[0047] The gas-solid feed pipe 6 has a particle inlet 61. The two ends of the gas-solid feed pipe 6 are a gas phase inlet 62 and a gas-solid outlet 63, respectively. The particle inlet 61 is located between the gas phase inlet 62 and the gas-solid outlet 63. The gas-solid outlet 63 is connected to the reaction bed section 11.

[0048] The feeding mechanism 7 is provided with a first feed inlet 71, a second feed inlet 72 and a discharge outlet 73. The second feed inlet 72 is located between the first feed inlet 71 and the discharge outlet 73. The first feed inlet 71 is connected to the silo, the second feed inlet 72 is connected to the circulation pipe 4, and the discharge outlet 73 is connected to the particle inlet 61 of the gas-solid feed pipe 6.

[0049] When the solid phase reaction time at control valve 3 is sufficient, control valve 3 will connect the outlet pipe 5 to the downflow bed section 13.

[0050] When the solid-phase reaction time to control valve 3 is insufficient, control valve 3 connects circulation pipe 4 to the downflow bed section 13.

[0051] The reactor of the present invention, applicable to ultrafine particle vapor deposition, achieves automatic adjustment of the apparent gas velocity entering the conveying bed 12 by setting a reaction bed section 11 with a diameter ratio of 1.1 to 3, thereby carrying out the solid product through the conveying bed. At the same time, by setting a gas phase nozzle in the descending bed section 13, conditions are provided for the solid product to undergo secondary reaction as needed, and an anti-backflow component 2 is simultaneously set to prevent the gas phase in the descending bed section 13 from flowing back into the conveying bed section 12, thereby affecting the conveying and separation of the gas-solid mixture in the conveying bed section 12. In addition, by setting a circulation pipe 4 selectively connected to the feeding mechanism 7, it is convenient for solid products that do not meet the preset requirements to return to the reaction bed section 11 for recycling reaction.

[0052] Specifically, such as Figure 1 and Figure 2 As shown, the reactor suitable for ultrafine particle vapor deposition includes a reactor body 1, a gas-solid feed pipe 6, and a feeding mechanism 7. The reactor body 1 has a reaction bed section 11, a conveying bed section 12, and a descending bed section 13 connected in sequence. The diameter of the reaction bed section 11 is larger than the diameter of the conveying bed section 12. A diameter-reduction structure 14 is formed at the connection between the reaction bed section 11 and the conveying bed section 12. A gas phase outlet 121 is opened downstream of the conveying bed section 12 along the solid phase conveying direction within the reactor body 1. The solid phase conveying direction within the reactor body 1 is as follows: Figure 1As shown by the middle arrow, an anti-backflow component 2 is provided at the connection between the conveying bed section 12 and the descending bed section 13. At least one gas phase feed hole group 130 is provided on the descending bed section 13. The gas phase feed hole group 130 includes at least one gas phase feed hole 131. A gas phase nozzle is connected to the gas phase feed hole 131. A control valve 3 is connected to the end of the descending bed section 13. A circulation pipe 4 and an outlet pipe 5 are connected to the control valve 3. That is, the descending bed section 13 is selectively connected to the circulation pipe 4 or the outlet pipe 5 through the control valve 3. When the solid phase reaction time at the control valve 3 is sufficient, the control valve 3 connects the outlet pipe 5 to the descending bed section 13. When the solid phase reaction time at the control valve 3 is insufficient, the control valve 3 connects the circulation pipe 4 to the descending bed section 13. In this embodiment, the gas phase outlet 121 of the conveying bed section 12 is connected to a gas-solid filter for further separation of the unseparated solid phase product. The end of the conveying bed section 12 is provided with a material leg 15 that can extend into the descending bed section 13. A triangular cone-shaped anti-backflow member 2 is provided directly below the material leg 15. Along the direction of gravity, the projection of the anti-backflow member 2 can fully cover the projection of the material leg 15.

[0053] The gas-solid feed pipe 6 has a gas phase inlet 62 and a gas-solid outlet 63 at its two ends. A particle inlet 61 is provided between the gas phase inlet 62 and the gas-solid outlet 63. The gas phase inlet 62 is connected to an external gas phase supply, and the gas-solid outlet 63 is connected to the reaction bed section 11.

[0054] The feeding mechanism 7 has a first feed inlet 71, a discharge outlet 73, and a second feed inlet 72 located between the first feed inlet 71 and the discharge outlet 73. The first feed inlet 71 is connected to an external silo, the second feed inlet 72 is connected to a circulation pipe 4, and the discharge outlet 73 is connected to the particle inlet 61 of the gas-solid feed pipe 6.

[0055] According to one embodiment of the present invention, the diameter ratio of the reaction bed section 11 to the transport bed section 12 is 1.1 to 3.

[0056] In this embodiment, the apparent gas velocity is automatically increased from the range of a fast bed or turbulent bed to a value greater than the vertical carry-out velocity of the solid product after passing through the narrowing structure 14 that connects the reaction bed section 11 and the conveying bed section 12, thereby carrying out and conveying the solid product.

[0057] Specifically, such as Figure 1 As shown, the ratio between the diameter D1 of the reaction bed section 11 and the diameter D2 of the conveying bed section 12 is in the range of 1.1 to 3. That is, along the solid phase conveying direction in the reactor body 1, the ratio of the diameter of the upstream end to the diameter of the narrowing structure 14 is 1.1 to 3.

[0058] According to one embodiment of the present invention, at least one diffuser 8 is provided in the reaction bed section 11. The diffuser 8 is connected to the gas-solid outlet 63 of the gas-solid feed pipe 6. The outlet end of the diffuser 8 has a plurality of outlets spaced apart.

[0059] In this embodiment, the diffuser 8 uniformly disperses the gas-solid mixture entering from the gas-solid feed pipe 6 within the reaction bed section 11.

[0060] Specifically, such as Figure 1 and Figure 2 As shown, the reaction bed section 11 is provided with at least one diffuser 8 connected to the gas-solid outlet 63 of the gas-solid feed pipe 6, and the outlet end of the diffuser 8 has multiple outlets spaced apart. In this embodiment, the diffuser 8 is shaped like a shower head.

[0061] According to one embodiment of the present invention, a loop distributor 9 is also provided in the reaction bed section 11, and the loop distributor 9 is located upstream of multiple outlets of the diffusion distributor 8 along the solid phase transport direction in the reactor body 1.

[0062] In this embodiment, the ring-type distributor 9 fully distributes the gas-solid two-phase mixture entering through the diffuser distributor 8 in the reaction bed section 11, further enhancing the fluidization effect of ultrafine particles in the reaction bed section 11 and preventing ultrafine particles from depositing at the bottom of the reaction bed section 11 to form a dead zone.

[0063] Specifically, such as Figure 1 and Figure 2 As shown, a loop distributor 9 is also provided in the reaction bed section 11. Along the solid phase transport direction in the reactor body 1, the loop distributor 9 is located upstream of multiple outlets of the diffuser distributor 8, that is, along the direction of gravity, each outlet of the diffuser distributor 8 is higher than the loop distributor 9.

[0064] According to one embodiment of the present invention, see reference. Figure 2 As shown, at least one packing internal component 10 is provided in the reaction bed section 11. Along the solid phase conveying direction in the reactor body 1, the cross-sectional profile of at least one packing internal component 10 coincides with the inner wall of the reaction bed section 11.

[0065] In this embodiment, the packing internals 10 provided in the reaction bed section 11 can enhance the mass transfer and reaction between the ultrafine particles and the gas phase.

[0066] Specifically, such as Figure 2As shown, at least one packing internal member 10 is provided in the reaction bed section 11. Along the solid phase conveying direction in the reactor body 1, the packing internal member 10 is located downstream of the reaction bed section 11, and the cross-sectional profile of the packing internal member 10 coincides with the inner wall of the reaction bed section 11, that is, the packing internal member 10 fills the reaction bed section 11 in the radial direction. In this embodiment, the number of packing internal members 10 is 1 to 10 layers.

[0067] According to one embodiment of the present invention, a gas-solid ultra-short rapid separation structure 120 is formed downstream of the conveying bed section 12 along the solid phase conveying direction within the reactor body 1, and a gas phase outlet 121 is provided on the gas-solid ultra-short rapid separation structure 120.

[0068] In this embodiment, the gas-solid mixture reaching the downstream of the conveying bed section 12 is rapidly separated under the combined action of inertial separation and centrifugal separation of the gas-solid ultra-short-fast separation structure 120. The separated gas phase is drawn out from the gas phase outlet 121, while the solid phase product enters the downward bed section 13 under the action of gravity.

[0069] Specifically, such as Figure 1 and Figure 2 As shown, along the solid phase transport direction within the reactor body 1, a gas-solid ultra-short rapid separation structure 120 is formed downstream of the transport bed section 12, and a gas phase outlet 121 is opened on the gas-solid ultra-short rapid separation structure 120.

[0070] According to one embodiment of the present invention, a gas-solid separation structure 132 is formed downstream of the downflow bed section 13 along the solid phase transport direction within the reactor body 1, and a control valve 3 is connected to the end of the gas-solid separation structure 132.

[0071] In this embodiment, the solid product separated by the gas-solid separation structure 132 is either drawn out from the outlet pipe 5 or returned to the reaction bed section 11 for circulation via the circulation pipe 4 under the selective connection of the control valve 3.

[0072] Specifically, such as Figure 1 and Figure 2 As shown, along the solid phase transport direction within the reactor body 1, a gas-solid separation structure 132 is formed downstream of the downflow bed section 13, and a control valve 3 is located at the end of the gas-solid separation structure 132.

[0073] According to one embodiment of the present invention, a plurality of gas phase feed hole groups 130 are provided on the downward bed section 13 along the solid phase conveying direction in the reactor body 1. Each gas phase feed hole group 130 has a plurality of gas phase feed holes 131. The plurality of gas phase feed holes 131 are spaced apart along the circumferential direction of the downward bed section 13, and each gas phase feed hole 131 is connected to a gas phase nozzle.

[0074] In this embodiment, the gas phase feed adopts a multi-nozzle combination, which facilitates flexible switching of different gas phase feedstocks according to the reaction requirements in the downward bed section 13.

[0075] Specifically, such as Figure 1 and Figure 2 As shown, along the solid phase conveying direction within the reactor body 1, a plurality of gas phase feed hole groups 130 are provided on the descending bed section 13. Each gas phase feed hole group 130 has a plurality of gas phase feed holes 131, which are spaced apart along the circumference of the descending bed section 13. Each gas phase feed hole 131 is connected to a gas phase nozzle. In this embodiment, 1 to 10 gas phase feed hole groups 130 are provided on the descending bed section 13, and each gas phase feed hole group 130 has 2 to 8 gas phase feed holes 131 evenly arranged along the circumference of the descending bed section 13.

[0076] According to one embodiment of the present invention, the angle α between the gas injection direction of the gas phase nozzle and the solid phase conveying direction within the reactor body 1 is 10° to 170°.

[0077] In this embodiment, the feed gas can be injected through a nozzle with an appropriate angle according to the reaction requirements. When an ultra-short residence time is required, the feed gas is injected through a gas phase nozzle arranged at an angle downwards. When the reaction requires a secondary reaction, the feed gas is injected through a gas phase nozzle arranged at an angle upwards or horizontally.

[0078] Specifically, such as Figure 1 and Figure 2 As shown, the angle between the gas injection direction of the gas phase nozzle and the solid phase conveying direction in the reactor body 1 is α. The value of α ranges from 10° to 170°, that is, the gas phase nozzle can be arranged obliquely upward, obliquely downward or horizontally.

[0079] According to one embodiment of the present invention, the gas phase velocity at the outlet of the gas phase nozzle is 10 m / s to 80 m / s.

[0080] In this embodiment, the feed gas can achieve full and rapid contact with the solid phase product in the downward bed section 13 within a gas velocity range of 10m / s to 80m / s.

[0081] Specifically, the velocity of the gas phase injected into the downward bed section 13 through the gas phase nozzle is 10 m / s to 80 m / s.

[0082] A method for ultrafine particle vapor deposition, implemented using a reactor as described above, includes the following steps:

[0083] The feeding mechanism 7 is turned on to introduce ultrafine particles, and at the same time the gas phase supply of the gas-solid feed pipe 6 is turned on to introduce reaction gas and fluidizing gas into the reaction bed section 11, so as to maintain the apparent gas velocity in the reaction bed section 11 in a turbulent bed or fast bed state.

[0084] When the solid phase reaction time entering the downflow bed section 13 is sufficient and no secondary reaction is required, control valve 3 connects the outlet pipe 5 to the downflow bed section 13, and the solid phase is drawn out from the outlet pipe 5. When the solid phase reaction time entering the downflow bed section 13 is insufficient, or when the solid phase reaction time entering the downflow bed section 13 is sufficient but a secondary reaction is required, the gas phase nozzle is opened to introduce reaction gas and fluidizing gas into the downflow bed section 13. When the solid phase reaction time reaching control valve 3 is sufficient, or when the solid phase reaching control valve 3 has completed the secondary reaction, control valve 3 connects the outlet pipe 5 to the downflow bed section 13, and the solid phase is drawn out from the outlet pipe 5. When the solid phase reaction time reaching control valve 3 is insufficient, control valve 3 connects the circulation pipe 4 to the downflow bed section 13, and the solid phase is sent back to the reaction bed section 11 to continue the gas phase deposition reaction.

[0085] The present invention provides a method for ultrafine particle vapor deposition that achieves the dual purpose of maintaining the apparent gas velocity and avoiding dead zones in the reaction bed section 11 by adjusting the gas phase supply in the gas-solid feed pipe 6; at the same time, the feed gas is injected through the gas phase nozzles provided in the downward bed section 13, so that the solid product can undergo secondary reaction as needed; and the solid product can be extracted or recycled through the control valve 3, thereby achieving quality control of the solid product.

[0086] Specifically, the method for ultrafine particle vapor deposition is implemented using the reactor described above, and includes the following steps:

[0087] Step S1: The feeding mechanism 7 is activated to introduce ultrafine particles. Simultaneously, the gas-solid feed pipe 6 and the ring-type distributor 9 are activated to supply gas phase into the reaction bed section 11, introducing reactive gas and fluidizing gas. During this process, the ring-type distributor 9 ensures that the gas and solid phases entering through the diffusion distributor 8 are fully distributed within the reaction bed section 11, and also replenishes the gas volume within the reaction bed section 11 to maintain the apparent gas velocity within the reaction bed section 11 in a turbulent or fast-flowing bed state. In this embodiment, the reactive gas is one of silane (SiH4) and trichlorosilane (SiHCl3), and the fluidizing gas is nitrogen (N2). This invention does not impose any limitations on these properties.

[0088] Step S2: When the solid phase reaction time entering the downflow bed section 13 is sufficient and a secondary reaction is not required, the control valve 3 connects the outlet pipe 5 to the downflow bed section 13, and the solid phase is drawn out from the outlet pipe 5. When the solid phase reaction time entering the downflow bed section 13 is insufficient, or when the solid phase reaction time entering the downflow bed section 13 is sufficient but a secondary reaction is required, the gas phase nozzle is opened to introduce reaction gas and fluidizing gas into the downflow bed section 13. When the solid phase reaction time reaching the control valve 3 is sufficient, or when the solid phase reaching the control valve 3 has completed the secondary reaction, the control valve 3 connects the outlet pipe 5 to the downflow bed section 13, and the solid phase is drawn out from the outlet pipe 5. When the solid phase reaction time reaching the control valve 3 is insufficient and a cyclic reaction is required, the control valve 3 connects the circulation pipe 4 to the downflow bed section 13, and the solid phase is sent back to the reaction bed section 11 via the feeding mechanism 7 to continue the gas phase deposition reaction. In this embodiment, when the vapor deposition reaction is carried out in the downstream bed section 13, the reaction gas and fluidizing gas entering through the vapor nozzle are the same as the reaction gas and fluidizing gas introduced into the reaction bed section 11 in step S1; when the carbon coating reaction is carried out in the downstream bed section 13, the reaction gas entering through the vapor nozzle is acetylene (C2H2) and the fluidizing gas is nitrogen (N2); the present invention does not limit this.

[0089] The above descriptions are merely a few embodiments of the present invention. Those skilled in the art can make various modifications or variations to the embodiments of the present invention based on the content disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A reactor suitable for use in the vapor deposition of ultrafine particles, characterized in that, include: The reactor body has a reaction bed section, a conveying bed section, and a descending bed section connected in sequence. The diameter of the reaction bed section is larger than the diameter of the conveying bed section. A gas phase outlet is provided on the conveying bed section. An anti-backflow component is provided at the connection between the conveying bed section and the descending bed section. At least one set of gas phase feed holes is provided on the descending bed section. Each set of gas phase feed holes has at least one gas phase feed hole. A gas phase nozzle is connected to the gas phase feed hole. A control valve is connected to the end of the descending bed section. A circulation pipe and an outlet pipe are connected to the control valve. A gas-solid feed pipe is provided with a particle inlet. The two ends of the gas-solid feed pipe are a gas phase inlet and a gas-solid outlet, respectively. The particle inlet is located between the gas phase inlet and the gas-solid outlet. The gas-solid outlet is connected to the reaction bed section. The feeding mechanism is provided with a first feed inlet, a second feed inlet and a discharge outlet. The second feed inlet is located between the first feed inlet and the discharge outlet. The first feed inlet is connected to the hopper. The second feed inlet is connected to the circulation pipe. The discharge outlet is connected to the particle inlet of the gas-solid feed pipe. When the solid-phase reaction time at the control valve is sufficient, the control valve connects the outlet pipe to the downward bed section; When the solid-phase reaction time to the control valve is insufficient, the control valve connects the circulation pipe to the downward bed section.

2. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, The diameter ratio of the reaction bed section to the transport bed section is 1.1 to 3.

3. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, At least one diffusion distributor is provided in the reaction bed section. The diffusion distributor is connected to the gas-solid outlet of the gas-solid feed pipe. The outlet end of the diffusion distributor has multiple outlets spaced apart.

4. The reactor for ultrafine particle vapor deposition according to claim 3, characterized in that, The reaction bed section is also equipped with a loop distributor, which is located upstream of multiple outlets of the diffusion distributor along the solid phase transport direction within the reactor body.

5. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, The angle between the gas injection direction of the gas phase nozzle and the solid phase transport direction within the reactor body is 10° to 170°.

6. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, The gas phase velocity at the outlet of the gas phase nozzle is 10 m / s to 80 m / s.

7. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, The reaction bed section is provided with at least one packing internal component, and the cross-sectional profile of at least one of the packing internal components coincides with the inner wall of the reaction bed section along the solid phase transport direction within the reactor body.

8. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, Along the solid phase transport direction within the reactor body, a gas-solid ultra-short rapid separation structure is formed downstream of the transport bed section, and the gas phase outlet is provided on the gas-solid ultra-short rapid separation structure.

9. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, Along the solid phase transport direction within the reactor body, a gas-solid separation structure is formed downstream of the downflow bed section, and the control valve is connected to the end of the gas-solid separation structure.

10. The reactor for ultrafine particle vapor deposition according to claim 1, characterized in that, Along the solid phase conveying direction within the reactor body, multiple gas phase feed hole groups are provided on the downward bed section. Each of the gas phase feed hole groups has multiple gas phase feed holes, and the multiple gas phase feed holes are spaced apart along the circumferential direction of the downward bed section. Each gas phase feed hole is connected to a gas phase nozzle.

11. A method for ultrafine particle vapor deposition, characterized in that, The method is implemented using a reactor suitable for ultrafine particle vapor deposition as described in any one of claims 1-10, and includes the following steps: The feeding mechanism is turned on to introduce ultrafine particles, and the gas-solid feed pipe is turned on at the same time to introduce reaction gas and fluidizing gas into the reaction bed section, maintaining the apparent gas velocity in the reaction bed section in a turbulent bed or fast bed state. When the solid phase reaction time entering the downflow bed section is sufficient and no secondary reaction is required, the control valve connects the outlet pipe to the downflow bed section, allowing the solid phase to be drawn out from the outlet pipe. When the solid phase reaction time entering the downflow bed section is insufficient, or when the solid phase reaction time entering the downflow bed section is sufficient but a secondary reaction is required, the gas phase nozzle is opened to introduce reaction gas and fluidizing gas into the downflow bed section. When the solid phase reaction time reaching the control valve is sufficient, or when the solid phase reaching the control valve has completed the secondary reaction, the control valve connects the outlet pipe to the downflow bed section, allowing the solid phase to be drawn out from the outlet pipe. When the solid phase reaction time reaching the control valve is insufficient and a cyclic reaction is required, the control valve connects the circulation pipe to the downflow bed section, sending the solid phase back to the reaction bed section to continue the gas phase deposition reaction.

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