Vertical powder continuous purification furnace

Abstract

The invention discloses a vertical continuous powder purification furnace, which relates to the technical field of high-purity powder purification and solves the technical problem of gasified impurity discharge rate of existing powder purification furnaces. The invention mainly relates to a crucible assembly, which is composed of a crucible unit composed of a plurality of upper and lower crucibles with openings at both ends. An upper crucible cone is arranged in the upper crucible, and the bottom of the side surface is connected to the upper crucible barrel wall through a crucible ring with a plurality of through holes. A lower crucible cone is arranged in the lower crucible, and the top of the lower crucible cone is provided with through holes. Ventilation pipes are arranged on the sides of the upper and lower crucible cones. The invention designs the purification furnace body as a vertical structure, and at the same time vertically and longitudinally arranges a series of crucible combinations one by one in the vertical furnace body, so as to increase the contact area and contact time between the powder and the process gas, so that the impurities can react more fully with the process gas, and the gasified impurities are discharged from the furnace body, so as to realize the continuous production of high-purity powder.

Description

Technical Field

[0001] The invention relates to high-purity powder production equipment, in particular to a vertical powder continuous purification furnace. Background Art

[0002] With the advancement of science and technology and the rapid development of high-end manufacturing industries, there is an increasing demand for high-end materials, including various high-purity powders, such as silicon carbide, aluminum nitride, graphite, etc. Powders are purified in high-temperature low-vacuum furnaces. During the powder purification process, it is necessary to ensure that heat can be conducted in and gasified impurities can be discharged, and continuous production is required. However, the existing powder purification furnace has a single crucible structure, and the generated gasified impurities are discharged inefficiently and incompletely, resulting in a decrease in powder purity and low quality of the final product. Summary of the invention

[0003] The present invention overcomes the shortcomings of the prior art and proposes a vertical continuous powder purification furnace, thereby solving the technical problem of the gasification impurity discharge rate of the prior powder purification furnace.

[0004] In order to achieve the above object, the present invention is implemented through the following technical solutions.

[0005] A vertical continuous powder purification furnace comprises a furnace body, wherein a heating system and a crucible assembly are arranged in the furnace body, a heat preservation device is arranged outside the crucible assembly, the crucible assembly is composed of a plurality of crucible units connected longitudinally from the top to the bottom of the furnace body, the crucible unit comprises an upper crucible and a lower crucible connected up and down, and both the upper crucible and the lower crucible are barrel bodies with openings at both ends; a bottomless upper crucible cone is arranged in the upper crucible barrel body, the bottom of the side surface of the upper crucible cone is connected to the upper crucible barrel wall through a crucible ring, and the crucible ring is provided with a plurality of through holes; a vent pipe is arranged on the side surface of the upper crucible cone; a bottomless lower crucible cone is arranged in the lower crucible barrel body, the bottom of the side surface of the lower crucible cone is fixedly connected to the upper end of the lower crucible barrel wall, and the top of the lower crucible cone is provided with through holes; a vent pipe is arranged on the side surface of the lower crucible cone; the top of the crucible assembly is connected to the exhaust pipe and the feed port arranged on the furnace body, and the bottom of the crucible assembly is connected to the discharge port arranged on the furnace body.

[0006] Furthermore, the ventilation pipe on the side of the upper crucible cone is arranged at 90 degrees with the ventilation pipe on the side of the lower crucible cone.

[0007] Furthermore, two ventilation pipes are symmetrically arranged on the side surface of the upper crucible cone and the side surface of the lower crucible cone, respectively.

[0008] Furthermore, the upper crucible cone and the lower crucible cone are both conical structures.

[0009] Furthermore, the feed port is connected to a feeding device, and the feeding device is connected in parallel with a plurality of feeding tanks.

[0010] Furthermore, the discharge port is connected to a discharge device, and the discharge device is connected in parallel with a plurality of receiving tanks.

[0011] Furthermore, a sealing structure is provided at the connection between the exhaust pipe and the furnace body.

[0012] Furthermore, the exhaust pipe is connected to a condenser, and the condenser is connected to a vacuum system.

[0013] Furthermore, an air inlet is provided at the bottom of the furnace body.

[0014] The beneficial effects of the present invention compared with the prior art are as follows.

[0015] The present invention uses a vertical continuous powder purification furnace structure. A high temperature environment is achieved in the furnace body through a heating system and a thermal insulation felt, and a high vacuum environment is achieved through a vacuum system. The induction heating system heats the crucible in the center of the furnace body to a high temperature, and the powder slides down from top to bottom along the crucible combination by gravity. The powder is tightly fitted with the high-temperature crucible during the sliding process, and the thickness of the flowing powder is very thin. The powder slides down along each layer of the crucible combination until it is discharged from the furnace body. The process gas enters from the bottom of the crucible combination and fully reacts with the powder flowing on the vertebral wall. The boiling point of the impurities after the reaction is lower than the temperature in the furnace, and the impurities are vaporized. The vaporized impurities are discharged step by step from bottom to top along the vent pipe in the crucible combination, achieving high-efficiency and high-quality continuous purification. The high-purity powder falls into the spiral material collector through the cooling stage and is then received in the material collecting tank.

[0016] The present invention breaks the structure of the traditional purification furnace and designs the purification furnace body as a vertical structure. At the same time, a combination of crucibles connected in series is vertically and longitudinally arranged in the vertical furnace body, so that the powder can be purified in the high-temperature low-vacuum furnace while ensuring that heat can be conducted into the furnace, thereby increasing the contact area and contact time between the powder and the process gas, so that the impurities can react more fully with the process gas, and the gasified impurities can be effectively discharged from the furnace body, thereby realizing the continuous production of high-purity powder. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the vertical continuous powder purification furnace of the present invention.

[0018] Figure 2 This is a top view of the upper crucible of the present invention.

[0019] Figure 3 for Figure 2 AA view.

[0020] Figure 4 This is a top view of the lower crucible of the present invention.

[0021] Figure 5 for Figure 4 AA view.

[0022] Figure 6 Gas flow diagram.

[0023] Figure 7 This is the powder flow diagram.

[0024] Among them, 1 is the first material receiving tank, 2 is the second material receiving tank, 3 is the first valve, 4 is the second valve, 5 is the spiral material receiving machine, 6 is the first air inlet, 7 is the cooling zone, 8 is the heating zone, 9 is the furnace shell, 10 is the induction heating system, 11 is the upper crucible assembly, 12 is the lower crucible assembly, 13 is the insulation felt, 14 is the spiral feeder, 15 is the third valve, 16 is the fourth valve, 17 is the first feeding tank, 18 is the second feeding tank, 19 is the exhaust pipe, 20 is the fifth valve, 21 is the condenser, 22 is the vacuum system, 23 is the condenser slag discharge port, 24 is the second air inlet, 25 is the upper crucible barrel, 26 is the ventilation pipe, 27 is the upper crucible cone, 28 is the crucible ring, 29 is the lower crucible barrel, and 30 is the lower crucible cone. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer, the present invention is further described in detail in conjunction with the embodiments and the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. The technical solutions of the present invention are described in detail below in conjunction with the embodiments and the accompanying drawings, but the scope of protection is not limited thereto.

[0026] like Figure 1 As shown, it is a vertical continuous powder purification furnace. In the middle of the furnace body are multiple crucible assemblies composed of an upper crucible assembly 11 and a lower crucible assembly 12 which are screwed together in multiple layers. An exhaust pipe 19 is arranged on the upper side wall of the furnace shell 9. The exhaust pipe 19 is screwed to the crucible part at the top of the crucible assembly and is fixed to the furnace shell 9 by a bolt sealing ring to ensure that the airflow in the crucible assembly is isolated from the gas between the crucible assembly and the furnace shell 9, so as to ensure that the impurity gas volatilized in the powder is not discharged into the furnace shell 9.

[0027] The upper crucible assembly 11 is composed of an upper crucible barrel 25 with openings at both ends, a vent pipe 26, an upper crucible cone 27, and a crucible ring 28. The crucible ring 28 is screwed to the bottom of the upper crucible barrel 25, and the bottom of the side of the upper crucible cone 27 is screwed to the crucible ring 28. The side of the upper crucible cone 27 is symmetrically screwed with two vent pipes 26 as a gas passage. Figure 2 and 3 shown.

[0028] The lower crucible assembly 12 is composed of a vent pipe 26, a lower crucible barrel 29 with openings at both ends, and a lower crucible cone 30. The bottom of the side of the lower crucible cone 30 is screwed into the top barrel wall of the lower crucible barrel 29. The side of the lower crucible cone 30 is also symmetrically screwed with two vent pipes 26. Figure 4 and Figure 5 As shown. The vent pipe 26 in the upper crucible assembly 11 and the vent pipe 26 in the lower crucible assembly 12 are arranged at 90 degrees. During the purification process, the powder slides down along the upper crucible cone 27 and the lower crucible cone 30, and the process gas and impurity gas are discharged along the vent pipe 26, as shown in FIG. Figure 6 and Figure 7 shown.

[0029] The top of the crucible assembly is connected to the exhaust pipe 19 and the feed port provided on the furnace body, and the bottom of the crucible assembly is connected to the discharge port provided on the furnace body. The feed port is connected to a screw feeder 14, and the screw feeder 14 is connected in parallel with a first feed tank 17 and a second feed tank 18. The discharge port is connected to a screw receiver 5, and the screw receiver 5 is connected in parallel with a first receiving tank 1 and a second receiving tank 2. The exhaust pipe 19 is connected to a condenser 21, and the condenser 21 is connected to a vacuum system 22. The bottom of the furnace body is provided with a first air inlet 6 and a second air inlet 24. The inlet of the first receiving tank 1 is provided with a first valve 3, the inlet of the second receiving tank 2 is provided with a second valve 4, the inlet of the first feeding tank 17 is provided with a third valve 15, the inlet of the second feeding tank 18 is provided with a fourth valve 16, and the inlet of the condenser 21 is provided with a fifth valve 20. The upper part of the furnace body is a heating zone 8, and the lower part is a cooling zone 7.

[0030] Before purification, the first valve 3, the second valve 4, the third valve 15, and the fourth valve 16 are closed, and the fifth valve 20 is opened. The purification furnace is evacuated through the vacuum system 22. After reaching the required vacuum degree, the upper crucible assembly 11 and the lower crucible assembly 12 in the heating zone 8 are heated to the required temperature through the induction heating system 10. Then, the protective gas is filled in through the first air inlet 6, and the furnace pressure of the purification process is ensured by controlling the filling amount and the exhaust amount.

[0031] After the first feed tank 17 is filled with powder, it is evacuated and then protective gas is introduced. The gas pressure is consistent with or slightly higher than the furnace pressure. The powder is fed by gravity or pressure difference. The third valve 15 is opened and the powder is fed into the furnace at the required speed by the screw feeder 14. The powder slides down along the upper crucible cone 27 and the lower crucible cone 30 in the heating zone 8. In this process, impurities react with process gas. The boiling point of the impurity compounds after the reaction is lower than the furnace temperature. After the impurity compounds are vaporized, they are discharged out of the furnace along the vent pipe 26 and the exhaust pipe 19 and enter the condenser 21. The impurity compounds are solidified in the condenser 21 and stored at the bottom of the condenser 21. After a production cycle, the fifth valve 20 is closed, the vacuum system 22 is closed, and the impurities in the condenser 21 are cleaned through the condenser slag discharge port 23.

[0032] The first receiving tank 1 is evacuated and then filled with protective gas. The gas pressure is consistent with the gas pressure in the furnace, and the first valve 3 is opened. After being purified in the heating zone 8, the powder slides to the cooling zone 7 and then falls into the spiral collecting machine 5. The spiral collecting machine 5 collects the powder into the first receiving tank 1.

[0033] After the powder in the first feeding tank 17 is emptied, the third valve 15 is closed, the first feeding tank 17 is filled with protective gas, filled with powder, evacuated, and then filled with protective gas, and the gas pressure is consistent with or slightly higher than the furnace pressure.

[0034] After the second feeding tank 18 is filled with powder, it is evacuated and then filled with protective gas. The gas pressure is consistent with or slightly higher than the furnace pressure. The fourth valve 16 is opened to feed powder by gravity or pressure difference.

[0035] After the first receiving tank 1 is filled, the first valve 3 is closed, and the protective gas is filled to the furnace pressure, and the powder is discharged after the powder temperature drops to a specific temperature.

[0036] The second material receiving tank 2 is evacuated and then filled with protective gas. The gas pressure is consistent with the furnace pressure, and the second valve 4 is opened to start collecting materials.

[0037] This structure breaks the traditional purification furnace structure and designs the purification furnace body as a vertical structure. At the same time, a combination of crucibles connected in series are vertically and longitudinally arranged in the vertical furnace body, so that the powder can be purified in a high-temperature low-vacuum furnace while ensuring that heat can be conducted in, thereby increasing the contact area and contact time between the powder and the process gas, so that the impurities can react more fully with the process gas, and the gasified impurities can be effectively discharged from the furnace body, thereby realizing the continuous production of high-purity powder.

[0038] The above content is a further detailed description of the present invention in combination with a specific preferred embodiment. It cannot be determined that the specific embodiments of the present invention are limited to this. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the present invention, which should be regarded as belonging to the present invention and the scope of patent protection determined by the submitted claims.

Claims

1. A vertical continuous powder purification furnace, comprising a furnace body, wherein a heating system and a crucible assembly are arranged in the furnace body, and a heat preservation device is arranged outside the crucible assembly, characterized in that: The crucible assembly is composed of a plurality of crucible units connected longitudinally from the top to the bottom of the furnace body, the crucible unit comprising an upper crucible and a lower crucible connected up and down, both of which are barrel bodies with openings at both ends; a bottomless upper crucible cone is arranged in the upper crucible barrel body, the bottom of the side surface of the upper crucible cone is connected to the upper crucible barrel wall through a crucible ring, and the crucible ring is provided with a plurality of through holes; a vent pipe is arranged on the side surface of the upper crucible cone; a bottomless lower crucible cone is arranged in the lower crucible barrel body, the bottom of the side surface of the lower crucible cone is fixedly connected to the upper end of the lower crucible barrel wall, and the top of the lower crucible cone is provided with through holes; a vent pipe is arranged on the side surface of the lower crucible cone; the top of the crucible assembly is connected to the exhaust pipe and the feed port arranged on the furnace body, and the bottom of the crucible assembly is connected to the discharge port arranged on the furnace body.

2. The vertical continuous powder purification furnace according to claim 1, characterized in that: The ventilation pipe on the side of the upper crucible cone is arranged at 90 degrees with the ventilation pipe on the side of the lower crucible cone.

3. The vertical continuous powder purification furnace according to claim 2, characterized in that: Two ventilation pipes are symmetrically arranged on the side surface of the upper crucible cone and the side surface of the lower crucible cone.

4. The vertical continuous powder purification furnace according to claim 1, characterized in that: The upper crucible cone and the lower crucible cone are both conical structures.

5. The vertical continuous powder purification furnace according to claim 1, characterized in that: The feed port is connected with a feeding device, and the feeding device is connected with a plurality of feeding tanks in parallel.

6. The vertical continuous powder purification furnace according to claim 1, characterized in that: The material discharging port is connected with a material discharging device, and the material discharging device is connected with a plurality of material receiving tanks in parallel.

7. The vertical continuous powder purification furnace according to claim 1, characterized in that: A sealing structure is provided at the connection between the exhaust pipe and the furnace body.

8. The vertical continuous powder purification furnace according to claim 1, characterized in that: The exhaust pipe is connected to a condenser, and the condenser is connected to a vacuum system.

9. The vertical continuous powder purification furnace according to claim 1, characterized in that: An air inlet is arranged at the bottom of the furnace body.

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