Rotary furnace device for chemical vapor deposition

Abstract

The invention relates to a rotary furnace device for chemical vapor deposition, which comprises a rotary furnace body and an external heating device, the rotary furnace body sequentially comprises a feeding section, a reaction section and a cooling section, and the feeding section is provided with a tail gas filter used for intercepting solid materials in tail gas; a stirring device is arranged in the reaction section; a gas distribution heat exchange device is arranged between the reaction section and the cooling section and is used for inputting process gas to the reaction section; a process gas pipe and a protective gas pipe are arranged in the cooling section; the process gas pipe is connected with a gas distribution heat exchange device; the protective gas pipe is connected with an external protective gas source, supplies gas to the cooling section, promotes the materials to rise and exchanges heat with gas in the process gas pipe; the downstream side of the cooling section is a furnace body tail, the furnace body tail is connected with the rotary furnace body through a dynamic and static sealing device, the furnace body tail does not rotate, an exhaust port is formed in the top of the furnace body tail and used for exhausting redundant shielding gas, and a discharging port is formed in the bottom of the furnace body tail and used for exhausting cooled products.

Description

Technical Field

[0001] The invention belongs to the technical field of CVD coating, and in particular relates to a rotary furnace device for chemical vapor deposition. Background Art

[0002] Chemical vapor deposition coating technology is widely used in the processing of positive and negative electrode materials for batteries, and in the sintering, drying, and coating of various powders in pharmaceutical and chemical industries. The core of the technology is the rotary kiln equipment, and the CVD coating process is completed in the rotary kiln. Currently, the main problems with rotary kilns for CVD coating are the low yield of the coating process and the tar problem associated with low-temperature coating. When the exhaust gas is discharged from the rotary kiln, some materials are also discharged, reducing the yield of the final product. The coated material product discharged from the rotary kiln has a high temperature. After the product is discharged and comes into contact with the air, the temperature drops suddenly. The tar on the surface of the product will combine with the product material, resulting in poor fluidity and conductivity of the material. Summary of the Invention

[0003] In response to the above problems, the present invention provides a rotary furnace device for chemical vapor deposition, comprising a rotary furnace body and an external heating device. The rotary furnace body sequentially comprises a feeding section, a reaction section, and a cooling section. The feeding section is provided with an exhaust gas filter for intercepting solid materials in the exhaust gas; a stirring device is provided in the reaction section; an air distribution heat exchange device is provided between the reaction section and the cooling section for inputting process gas to the reaction section; a process gas pipe and a protective gas pipe are provided in the cooling section, and the process gas pipe is connected to the air distribution heat exchange device; the protective gas pipe is connected to an external protective gas source to supply gas to the cooling section, thereby causing the material to be lifted and exchanging heat with the gas in the process gas pipe; The downstream side of the cooling section is the tail of the furnace body, which is connected to the rotary furnace body through a dynamic and static sealing device. The tail of the furnace body does not rotate, and an exhaust port is provided at the top for discharging excess protective gas, and a discharge port is provided at the bottom for discharging the cooled product.

[0004] Optionally, a feeding device is connected to the upstream side of the feeding section of the rotary furnace body, and the feeding device is preferably a screw feeder. The feeding port of the screw feeder is located outside the rotary furnace body, and the tail of the screw feeder passes through the furnace end cover of the furnace head and enters the feeding section, and coincides with the central axis of the feeding section. The screw feeder is fixed.

[0005] Optionally, a tail gas filter is provided at the upstream end of the feeding section, and the tail gas filter is located above the tail of the screw feeder to facilitate the collection of cracked and unreacted tail gas from the reaction section; The exhaust gas filter includes a filter cage, one end of which is connected to the exhaust pipe, and the other end points in the direction of the reaction section. The exhaust pipe passes through the furnace end cover of the furnace body and is connected to a professional exhaust gas treatment device.

[0006] Optionally, the gas distribution heat exchange device includes a gas distribution plate and a rotating cover, the rotating cover is conical in shape with a horizontal central axis, the apex of the rotating cover points to the reaction section, the bottom surface is vertical and open, and the curved surface on the side of the rotating cover is a mesh surface, allowing the process gas to enter the reaction section through the rotating cover; the rotating cover is connected to the inner wall of the rotary furnace body and can rotate with the furnace body; The gas distribution plate is circular and parallel to the bottom surface of the rotating cover. A gas distribution pipe is provided on the side of the gas distribution plate facing the reaction section for releasing process gas, and a blowing pipe is provided on the side facing the cooling section for releasing protective gas.

[0007] Further optionally, the diameter of the bottom surface of the rotating cover is smaller than the diameter of the reaction section, and the edge of the bottom surface of the rotating cover is fixedly connected to the inner wall of the furnace body through a number of connecting rods, so that the rotating cover rotates with the furnace body; the mesh aperture of the rotating cover is smaller than the particle size of the material particles in the reaction section, thereby preventing the material at the tail of the reaction section from entering the rotating cover and affecting the gas distribution pipe.

[0008] Optionally, the cooling section is provided with a process gas section, a protective gas section and an air collecting section, and several process gas pipes of the process gas section are parallel to the central axis of the rotary furnace body and are evenly distributed on the longitudinal section of the cooling section; the air collecting section is arranged at the top of the cooling section, including a filter screen and an air collecting hood, and the air collecting hood is connected to an external heat exchange device through an exhaust port; several protective gas pipes of the protective gas section are evenly arranged at the bottom of the cooling section, for inputting inert gas into the cooling section, lifting the material and exchanging heat with the process gas.

[0009] Further optionally, a first through hole is provided in the center of the rear portion of the furnace body, and a gas source pipe of the process gas enters the cooling section through the first through hole, and the gas source pipe is connected in parallel to the rear portion of the process gas pipe for gas supply; the head portion of the process gas pipe reaches the gas distribution plate and supplies gas to the gas distribution pipe; A second through hole is provided at the lower part of the tail of the furnace body. The gas source pipe of the protective gas enters the cooling section through the second through hole and is connected in parallel to the tail of the protective gas pipe for supplying inert gas; the head of the protective gas pipe reaches the gas distribution plate and supplies gas to the blowing pipe.

[0010] Alternatively, several protective air pipes may be arranged in a row at the same height, with a certain distance between the protective air pipes and the bottom of the furnace body, allowing a certain amount of material to accumulate at the bottom of the cooling section; the air output of the air blowing pipes and the height of the protective air pipes may be adjusted to prevent the material at the bottom of the cooling section from flooding the protective air pipes; The sides and top of the protective air pipe are evenly provided with air outlet holes, which blow and lift the materials at the bottom of the cooling section. The rotation of the furnace body itself can also drive the movement of materials.

[0011] Further optionally, a heat exchange device is provided on the outside of the rotary furnace body, and the gas discharged from the gas collecting hood is input into the heat exchange device as a hot medium, and the process gas is input into the heat exchange device as a cold medium, and the cold and hot media undergo a first heat exchange to preheat the process gas; the hot medium of the heat exchange device is discharged and then the exhaust gas is treated.

[0012] Optionally, the discharge port is connected to a cooling pipe, and a sleeve is provided on the outside of the cooling pipe. The sleeve is used to input and output cooling water to cool the material product discharged from the discharge port. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of a rotary furnace device for chemical vapor deposition; Figure 2 Schematic diagram of the rotating hood, air distribution plate and process air pipe.

[0014] In the accompanying drawings, 1-rotary furnace body, 2-feeding section, 3-reaction section, 4-cooling section, 5-rear end of furnace body, 6-dynamic and static sealing device, 7-exhaust port, 8-discharge port, 9-heating device, 10-screw feeder, 11-filter cage, 12-tail gas pipe, 13-front agitator, 14-rear agitator, 15-dumping plate, 16-gas distribution plate, 17-rotating cover, 18-gas distribution pipe, 19-blowing pipe, 20-protective air pipe, 21-process air pipe, 22-filter, 23-gas collecting hood. DETAILED DESCRIPTION

[0015] This embodiment provides a rotary furnace device for chemical vapor deposition, such as Figure 1-Figure 2 As shown, the rotary furnace body 1 and the external heating device 9 are provided. The rotary furnace body 1 includes a feeding section 2, a reaction section 3 and a cooling section 4 in sequence. The feeding section 2 is provided with an exhaust filter for intercepting solid materials in the exhaust gas; the reaction section 3 is provided with a stirring device; an air distribution heat exchange device is provided between the reaction section 3 and the cooling section 4 for inputting process gas to the reaction section 3; a process gas pipe 21 and a protective gas pipe 20 are provided in the cooling section 4, and the process gas pipe 21 is connected to the air distribution heat exchange device; the protective gas pipe 20 is connected to an external protective gas source to supply gas to the cooling section 4, promote the lifting of materials, and exchange heat with the gas in the process gas pipe 21; The downstream side of the cooling section 4 is the furnace body tail 5, which is connected to the rotary furnace body 1 through a dynamic and static sealing device 6. The furnace body tail 5 does not rotate, and an exhaust port 7 is provided at the top for discharging excess protective gas, and a discharge port 8 is provided at the bottom for discharging the cooled product.

[0016] The present invention addresses the low yield of rotary furnaces by installing an exhaust filter upstream of the furnace body to filter and capture material in the exhaust, preventing it from exiting the furnace body with the exhaust gas, thereby improving the yield of the rotary furnace. Furthermore, a cooling section 4 is provided at the rear of the rotary furnace body 1. An air distribution heat exchanger separates the reaction section 3 from the cooling section 4, providing physical isolation for the cooling section 4. The material coated in the reaction section 3 is discharged into the cooling section 4 through the gap between the air distribution heat exchanger and the furnace body inner wall. The material in the cooling section 4 is lifted by the rotation of the furnace body and the action of the protective gas, and comes into contact with the process gas pipe 21, where it undergoes a primary heat exchange with the process gas. Excess protective gas in the cooling section 4 is discharged through an exhaust port 7, and the heat-exchanged material is discharged through a discharge port 8. The air distribution heat exchanger of the present invention not only ensures a more even distribution of the process gas entering the reaction section 3 but also allows for a secondary heat exchange between the material leaving the reaction section 3 and the process gas. This further heat exchange of the material using the air distribution heat exchanger and the cooling section 4 accelerates material cooling and utilizes heat. When the material is cooled in cooling section 4, it is protected by protective gas. Some substances that can produce tar after encountering air cooling are taken away by the protective gas. After the material is discharged from the furnace body, no tar will be produced, thereby improving product quality.

[0017] The rotary furnace body 1 is a conventional heating-type rotary furnace in the art. Specifically, the rotary furnace body 1 is cylindrical, and one or both ends of the furnace body are connected to a driving device to drive the rotary furnace body 1 to rotate. The outer side of the rotary furnace body 1 is covered with a heating device 9, such as a heating wire, a heating rod, etc., and the outer side of the heating device 9 is covered with an insulation layer to ensure heating efficiency. The heating device 9 and the insulation layer are fixed. The two ends of the rotary furnace body 1 are respectively provided with furnace end covers. The furnace end covers are rotatably connected to the furnace body through a dynamic and static sealing device 6, so that the furnace end covers do not rotate with the furnace body, while ensuring that the head and tail of the furnace body are leak-proof. The furnace end cover at the downstream end of the furnace body is the furnace body tail 5.

[0018] Optionally, a feeding device is connected to the upstream side of the feeding section 2 of the rotary furnace body 1, and the feeding device is preferably a screw feeder 10. The feeding port of the screw feeder 10 is located outside the rotary furnace body 1, and the tail of the screw feeder 10 passes through the furnace end cover of the furnace head and enters the feeding section 2, and coincides with the central axis of the feeding section 2. The screw feeder 10 is fixed.

[0019] The screw feeder 10 has relatively uniform feeding and good stability. It can continuously, uniformly and stably input raw materials according to the feeding amount requirement of the furnace body, which is conducive to the uniform coating / deposition of carbonaceous substances on the raw materials in the furnace body.

[0020] Optionally, a tail gas filter is provided at the upstream end of the feeding section 2, and the tail gas filter is located above the tail of the screw feeder 10 to facilitate the collection of cracked and unreacted tail gas from the reaction section 3; The exhaust filter consists of a filter cage 11, one end of which is connected to an exhaust pipe 12, and the other end points toward the reaction zone 3. The exhaust pipe 12 passes through the furnace end cap and is connected to a specialized exhaust treatment device. The exhaust filter is also stationary. The exhaust pipe 12 can also be connected to an external air bag to periodically blow air back into the filter cage 11 to remove trapped material from its surface.

[0021] Optionally, a stirring device is provided inside the reaction section 3 of the rotary furnace body 1. The stirring device is fixedly connected to the inner wall of the rotary furnace body 1 and can rotate with the rotary furnace body 1 to stir the material in the furnace body and promote full contact between the process gas and the material; the stirring device includes a front stirrer 13, a rear stirrer 14 and a plurality of pouring plates 15, and the plurality of pouring plates 15 are evenly distributed on the inner wall of the furnace body along the circumference and axial direction of the rotary furnace body 1. The front stirrer 13 is provided on the upstream side of the reaction section 3, and the rear stirrer 14 is provided on the downstream side. The pouring plate 15 is provided between the front and rear stirrers 14; the front and rear stirrers 14 are both existing double-helix or single-helix stirring blades.

[0022] Process gases (organic gases such as methane, ethylene, and acetylene) are fed into the downstream side of reaction section 3 through a gas distribution and heat exchanger. Raw materials are fed into feed section 2. Driven by the stirring device, the raw materials move toward cooling section 4, where they come into countercurrent contact within reaction section 3. In the high-temperature environment of 500-1000°C in reaction section 3, the process gases undergo a cracking reaction, producing carbonaceous solids. These solids come into contact with the raw materials and deposit on the surface of the raw material particles, coating them. The exhaust then exits the furnace through an exhaust filter, while the solids are discharged into cooling section 4.

[0023] Optionally, the gas distribution heat exchange device includes a gas distribution plate 16 and a rotating cover 17. The rotating cover 17 is conical in shape and has a horizontal central axis. The top of the rotating cover 17 points to the reaction section 3, the bottom surface is vertical and open, and the curved surface on the side of the rotating cover 17 is a mesh surface, allowing the process gas to enter the reaction section 3 through the rotating cover 17; the rotating cover 17 is connected to the inner wall of the rotary furnace body 1 and can rotate with the furnace body. The gas distribution plate 16 is circular and parallel to the bottom surface of the rotating cover 17. The side of the gas distribution plate 16 facing the reaction section 3 is provided with a gas distribution pipe 18 for releasing process gas, and the side facing the cooling section 4 is provided with a blowing pipe 19 for releasing protective gas.

[0024] Further optionally, the diameter of the bottom surface of the rotating cover 17 is smaller than the diameter of the reaction section 3, and the edge of the bottom surface of the rotating cover 17 is fixedly connected to the inner wall of the furnace body through a number of connecting rods, so that the rotating cover 17 rotates with the furnace body; the mesh aperture of the rotating cover 17 is smaller than the particle size of the material particles in the reaction section 3, thereby preventing the material at the tail of the reaction section 3 from entering the rotating cover 17 and affecting the gas distribution pipe 18.

[0025] Further optionally, the gas distribution plate 16 is vertical, the side of the gas distribution plate 16 facing the reaction section 3 is the front side, and the other side is the back side, the diameter of the gas distribution plate 16 is equal to the diameter of the bottom surface of the rotating cover 17, and there is a very small gap between the front surface of the gas distribution plate 16 and the bottom surface of the rotating cover 17, and the gas distribution plate 16 does not affect the rotation of the rotating cover 17; The upper half of the gas distribution plate is connected to a baffle in the shape of a circular ring. There is a very small gap between the edge of the baffle and the inner wall of the furnace body, which does not affect the rotation of the furnace body and prevents a large amount of process gas in the reaction section from entering the cooling section.

[0026] Optionally, gas distribution pipes 18 are evenly distributed on the front surface of the gas distribution plate 16, with gas outlets evenly distributed on the side of the gas distribution pipes 18 facing the reaction section 3. Blowing pipes 19 are evenly distributed on the back surface of the gas distribution plate 16, with gas outlets evenly distributed on the side of the gas blowing pipes 19 facing the cooling section 4. The shapes of the gas distribution pipes 18 and the blowing pipes 19 can be selected from a variety of options, including any existing uniformly arranged pipe configuration, such as a multi-circular arrangement or a multi-circular spiral arrangement.

[0027] The deposited and coated material gradually moves to the rear of the reaction section 3 under the propulsion of the stirring device. Rotating cover 17 occupies the majority of the longitudinal cross-section of the furnace. The stirring device lifts the material, so the surface of rotating cover 17 receives the majority of the material, preventing it from passing through. As it rotates, the material falls below it. The bottom edge of rotating cover 17 forms a channel connecting the reaction section 3 with the cooling section 4, through which any fallen material is discharged into the cooling section 4. A gas distribution plate 16 supplies process gas (possibly accompanied by carrier gas) to the reaction section 3. Rotating cover 17 protects gas distribution pipe 18 from material blockage. As gas passes through rotating cover 17, it promotes spiral gas input, imparting some kinetic energy to the gas and promoting contact between the gas and the material. Simultaneously, the gas blows back against the material particles on rotating cover 17, cleaning the surface and maintaining an unobstructed gas supply. On the other hand, the gas and the material contact on the rotating cover 17, which can carry out the last heat exchange. The temperature of the material at the end of the reaction section 3 is higher, which can preheat the gas for the last time and is also the first cooling before the material is discharged.

[0028] Optionally, the cooling section 4 is provided with a process gas section, a protective gas section and an air collecting section, and several process gas pipes 21 of the process gas section are parallel to the central axis of the rotary furnace body 1 and are evenly distributed on the longitudinal section of the cooling section 4; the air collecting section is arranged at the top of the cooling section 4, including a filter screen 22 and an air collecting hood 23, and the air collecting hood 23 is connected to an external heat exchange device through the exhaust port 7; several protective gas pipes 20 of the protective gas section are evenly arranged at the bottom of the cooling section 4, for inputting inert gas into the cooling section 4, lifting the material and exchanging heat with the process gas.

[0029] Further optionally, a first through hole is provided in the center of the tail portion 5 of the furnace body, and a gas source pipe of the process gas enters the cooling section 4 through the first through hole, and the gas source pipe is connected in parallel to the tail portion of the process gas pipe 21 for gas supply; the head portion of the process gas pipe 21 reaches the gas distribution plate 16 and supplies gas to the gas distribution pipe 18; A second through hole is provided at the lower part of the tail part 5 of the furnace body. The gas source pipe of the protective gas enters the cooling section 4 through the second through hole and is connected in parallel to the tail part of the protective gas pipe 20 for supplying inert gas. The head of the protective gas pipe 20 reaches the gas distribution plate 16 and supplies gas to the blowing pipe 19.

[0030] The present invention is provided with a cooling section 4 for cooling the material and preheating the process gas that is about to enter the reaction section 3. The heating device 9 does not cover the cooling section 4 portion of the furnace body, or only covers the head portion of the cooling section 4. The material enters the cooling section 4 from the lower channel of the air distribution heat exchange device, is blown and lifted by the inert gas input from the protective gas section, contacts the process gas pipe 21, and undergoes a second heat exchange with the process gas inside it. The inert gas provides a protective gas atmosphere for the cooling section 4, so that during the cooling process of the material, some organic matter on the surface of the material will not form tar, but will remain in the form of low molecular weight substances and be discharged from the furnace body along with the protective gas. This is also the process of cleaning the material product.

[0031] The protective gas in the cooling section 4 blows the material toward the side wall of the furnace body and upward. The material conveying channel in the lower half of the rotating cover 17 is mainly used to discharge the material. The protective gas in the cooling section 4 rarely enters the reaction section 3 through this channel. Even if it can enter the reaction section 3, it will not affect the reaction in the reaction section 3. Since the process gas input into the reaction section 3 is also accompanied by a carrier gas, the carrier gas is an inert gas and can be the same as the protective gas.

[0032] Excess gas in the cooling section 4 enters the gas collection section, where the filter 22 intercepts the material, allowing it to fall back into the lower middle section 4. The protective gas then exits the furnace through the gas collection hood 23 and the exhaust port 7. The air blow pipe 19 on the opposite side of the gas distribution plate 16 blows air toward the rear end 5 of the furnace, gradually blowing the increasing amount of material out to the rear end 5. There, the protective air pipe 20 is not used to drive the material, so the material falls by gravity and exits the furnace through the discharge port 8.

[0033] Further optionally, a plurality of process air pipes 21 are evenly distributed along the circumference and radial direction of the cooling section 4, which is conducive to full contact with the raised materials and improved heat exchange efficiency; the heads of the process air pipes 21 can pass through the air distribution plate 16 and then connect to the air distribution pipe 18, or the heads of the process air pipes 21 can first be gathered into one pipe, then pass through the air distribution plate 16, and then connect to the air distribution pipe 18.

[0034] Further optionally, a plurality of protective air pipes 20 are arranged in a row and at the same height, with a certain distance between the protective air pipe 20 and the bottom of the furnace body, allowing a certain amount of material to accumulate at the bottom of the cooling section 4; the air output of the blowing pipe 19 and the height of the protective air pipe 20 can be adjusted to prevent the material at the bottom of the cooling section 4 from submerging the protective air pipe 20; The side and top surfaces of the protective air pipe 20 are evenly provided with air outlet holes, which blow and lift the material at the bottom of the cooling section 4, and the rotation of the furnace body itself can also drive the material to move.

[0035] Because the furnace tail section 5 does not rotate, the two gas source pipes can stably extend into the cooling section 4. The process gas section and the protective gas section are both fixed and connected to the equally fixed gas distribution plate 16. The furnace tail section 5 is provided with an exhaust port 7, which is connected to the gas collection section via a pipe. The gas collection section is also fixed.

[0036] Further optionally, a heat exchange device is provided on the outside of the rotary furnace body 1, and the gas discharged from the gas collecting hood 23 is input into the heat exchange device as a hot medium, and the process gas is input into the heat exchange device as a cold medium. The cold and hot media undergo a first heat exchange to preheat the process gas; the hot medium of the heat exchange device is discharged and then the exhaust gas is treated.

[0037] Optionally, the discharge port 8 is connected to a cooling pipe, and a sleeve is provided on the outside of the cooling pipe. The sleeve is used to input and output cooling water to cool the material product discharged from the discharge port 8.

Claims

1. A rotary kiln device for chemical vapor deposition, characterized in that: The rotary furnace includes a rotary furnace body and an external heating device. The rotary furnace body includes a feeding section, a reaction section, and a cooling section in sequence. The feeding section is provided with an exhaust filter for intercepting solid materials in the exhaust gas. The reaction section is provided with a stirring device. An air distribution heat exchange device is provided between the reaction section and the cooling section for inputting process gas to the reaction section. The cooling section is provided with a process gas pipe and a protective gas pipe, and the process gas pipe is connected to the air distribution heat exchange device. The protective gas pipe is connected to an external protective gas source to supply gas to the cooling section, causing the material to be lifted and to exchange heat with the gas in the process gas pipe. The downstream side of the cooling section is the tail of the furnace body, which is connected to the rotary furnace body through a dynamic and static sealing device. The tail of the furnace body does not rotate, and an exhaust port is provided at the top for discharging excess protective gas, and a discharge port is provided at the bottom for discharging the cooled product.

2. The rotary kiln device for chemical vapor deposition according to claim 1, characterized in that: The upstream side of the feeding section of the rotary furnace body is connected to a screw feeder, the feeding port of the screw feeder is located outside the rotary furnace body, the tail of the screw feeder passes through the furnace end cover of the furnace head and enters the feeding section, and coincides with the central axis of the feeding section, and the screw feeder is fixed.

3. The rotary kiln device for chemical vapor deposition according to claim 1, characterized in that: An exhaust filter is provided at the upstream end of the feeding section. The exhaust filter is located above the tail of the screw feeder to collect the cracked and unreacted exhaust from the reaction section. The exhaust gas filter includes a filter cage, one end of which is connected to the exhaust pipe, and the other end points in the direction of the reaction section. The exhaust pipe passes through the furnace end cover of the furnace body and is connected to a professional exhaust gas treatment device.

4. The rotary kiln device for chemical vapor deposition according to claim 1, characterized in that: The gas distribution heat exchange device includes a gas distribution plate and a rotating cover. The rotating cover is conical in shape with a horizontal central axis. The top of the rotating cover points to the reaction section, the bottom surface is vertical and open, and the curved surface on the side of the rotating cover is a mesh surface, allowing process gas to pass through the rotating cover into the reaction section. The rotating cover is connected to the inner wall of the rotary furnace body and can rotate with the furnace body. The gas distribution plate is circular and parallel to the bottom surface of the rotating cover. A gas distribution pipe is provided on the side of the gas distribution plate facing the reaction section for releasing process gas, and a blowing pipe is provided on the side facing the cooling section for releasing protective gas.

5. The rotary kiln device for chemical vapor deposition according to claim 4, characterized in that: The diameter of the bottom surface of the rotating cover is smaller than the diameter of the reaction section, and the edge of the bottom surface of the rotating cover is fixedly connected to the inner wall of the furnace body through a plurality of connecting rods, so that the rotating cover rotates together with the furnace body; the mesh aperture of the rotating cover is smaller than the particle size of the material particles in the reaction section, thereby preventing the material at the tail of the reaction section from entering the rotating cover and affecting the gas distribution pipe.

6. The rotary kiln device for chemical vapor deposition according to claim 1, characterized in that: The cooling section is provided with a process gas section, a protective gas section and a gas collecting section. The process gas section has a plurality of process gas pipes parallel to the central axis of the rotary furnace body and evenly distributed on the longitudinal section of the cooling section. The gas collection part is located at the top of the cooling section, including a filter screen and a gas collection hood. The gas collection hood is connected to the external heat exchange device through the exhaust port. Several protective gas pipes of the protective gas part are evenly arranged at the bottom of the cooling section, which are used to input inert gas into the cooling section to lift the material and exchange heat with the process gas.

7. The rotary kiln device for chemical vapor deposition according to claim 6, characterized in that: A first through hole is provided at the center of the tail of the furnace body, and a gas source pipe for the process gas enters the cooling section through the first through hole. The gas source pipe is connected in parallel to the tail of the process gas pipe for gas supply; the head of the process gas pipe reaches the gas distribution plate and supplies gas to the gas distribution pipe; A second through hole is provided at the lower part of the tail of the furnace body. The gas source pipe of the protective gas enters the cooling section through the second through hole and is connected in parallel to the tail of the protective gas pipe for supplying inert gas; the head of the protective gas pipe reaches the gas distribution plate and supplies gas to the blowing pipe.

8. The rotary kiln device for chemical vapor deposition according to claim 7, characterized in that: Several protective gas pipes are arranged in a row at the same height. There is a distance between the protective gas pipes and the bottom of the furnace body, allowing a certain amount of material to accumulate at the bottom of the cooling section. The side and top surfaces of the protective air pipe are evenly provided with air outlet holes to blow and lift the materials at the bottom of the cooling section.

9. The rotary kiln device for chemical vapor deposition according to claim 6, characterized in that: A heat exchange device is provided on the outside of the rotary furnace body. The gas discharged from the gas collecting hood is input into the heat exchange device as a heat medium, and the process gas is input into the heat exchange device as a cold medium. The cold and hot media perform the first heat exchange to preheat the process gas; the hot medium of the heat exchange device is discharged for tail gas treatment.

10. The rotary kiln device for chemical vapor deposition according to claim 1, characterized in that: The discharge port is connected to a cooling pipe, and a sleeve is provided on the outside of the cooling pipe. The sleeve is used to input and output cooling water to cool the material product discharged from the discharge port.

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