Powder feeding system for preparing spherical silica powder

Abstract

The invention provides a powder feeding system for preparing spherical silica powder. The powder feeding system comprises a powder feeder, a tank body and a pipe body. The powder feeder comprises a cavity, and a through hole used for introducing first airflow is formed in the lower portion of the side wall of the cavity. The tank body is inverted, and a tank opening is communicated with the upper end of the cavity and used for supplying silica powder raw materials to the cavity. The pipe body penetrates through the cavity along the upper axis of the cavity and extends outwards, and a powder-carrying airflow input port and a powder-carrying airflow output port are formed in the pipe body.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of silicon powder preparation, and particularly relates to a powder feeding system for preparing spherical silicon powder. BACKGROUND

[0002] In recent years, the development of electronic information industries such as 5G communication, semiconductor and artificial intelligence has promoted the development of copper-clad plate and electronic packaging industries, and spherical silicon powder has become the main production material in these fields due to its good fluidity, low stress, small specific surface area and high bulk density. With the development of high frequency and high speed of electronic systems, the electronic information industry has higher requirements for the performance of raw materials, and the demand for spherical silicon powder with good performance such as high spheroidization degree and appropriate particle size has increased significantly, and stricter requirements have been put forward for the production process of spherical silicon powder.

[0003] Powder feeding is an important link in the preparation of spherical silicon powder, and the commonly used powder feeding methods at present include air-borne powder feeding, mechanical powder feeding, centrifugal powder feeding and scraper powder feeding. These methods are prone to cause problems such as powder agglomeration, particle morphology damage and uneven powder feeding, resulting in yield and quality reduction. SUMMARY

[0004] To solve the above and other aspects at least one technical problem in the prior art, the embodiments of the present disclosure provide a powder feeding system for preparing spherical silicon powder, which comprises a powder feeder, a tank body and a pipe body. The powder feeder comprises a cavity, and a through hole for introducing a first gas flow is arranged at the lower part of the side wall of the cavity. The tank body is inverted, and the tank opening is in communication with the upper end of the cavity for supplying silicon powder raw materials to the cavity. The pipe body penetrates the cavity along the upper axis of the cavity and extends outward, and the pipe body is provided with a powder-carrying gas flow inlet and a powder-carrying gas flow outlet.

[0005] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon powder further comprises a gas inlet. The gas inlet is arranged on the upper part of the side wall of the tank body and away from the tank opening, and is used for introducing a second gas flow into the tank body.

[0006] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon powder further comprises a gas overflow port. The gas overflow port is arranged on the side wall of the tank body and is on the same side of the tank body as the gas inlet.

[0007] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon powder further comprises a vibration vibrator. The vibration vibrator is connected to the powder feeder, and the vibration vibrator is connected to an output fixed frequency motor.

[0008] According to some embodiments of the present disclosure, the powder-carrying gas flow inlet and the powder-carrying gas flow outlet are each provided with a one-way valve for isolating the communication between the pipe body and the cavity.

[0009] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon micro-powder further comprises a power supply assembly. The power supply assembly is arranged at the powder carrying gas flow outlet, and is used to make the silicon micro-powder material flowing therethrough carry the same charge.

[0010] According to some embodiments of the present disclosure, the power supply assembly comprises an electrode and a high-voltage transformer power supply. The electrode is in the form of a plate, and the surface of the electrode is arranged with tungsten needles. The electrode is connected to the high-voltage transformer power supply, so that the tungsten needles can discharge.

[0011] According to some embodiments of the present disclosure, the tungsten needles are arranged in at least two rows symmetrically on the electrode, and each row of tungsten needles is arranged in the form of equal spacing.

[0012] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon micro-powder further comprises a screen. The screen is arranged inside the cavity and divides the cavity into an upper cavity and a lower cavity. The pore size of the screen is smaller than the particle size of the silicon micro-powder material, and is used to block the silicon micro-powder material from entering the lower cavity.

[0013] According to some embodiments of the present disclosure, the powder carrying gas flow inlet is arranged at the middle side of the pipe body, and the powder carrying gas flow outlet is arranged at the side of the pipe body close to the end.

[0014] According to the powder feeding system for preparing spherical silicon micro-powder provided by the present disclosure, first, the first gas flow is introduced from the through hole at the lower part of the side wall of the powder feeder cavity, and an upward gas flow field is formed in the cavity, which uniformly disturbs the silicon micro-powder material supplied by the tank body, breaks the molecular attraction between the particles of the silicon micro-powder material, reduces the agglomeration of the silicon micro-powder material, and forms a powder carrying gas flow together with the silicon micro-powder material. The particle distribution of the silicon micro-powder material dispersed in the powder carrying gas flow is more uniform, which helps to improve the uniformity of the particle heating in the subsequent spheroidization process and helps to improve the uniformity of the spheroidization degree of the spherical silicon micro-powder. Second, the tank body is inverted and the tank opening is communicated with the upper end of the cavity, so that the silicon micro-powder material can naturally fall into the cavity under the action of gravity, realizing stable and continuous powder feeding to the cavity, reducing the production interruption or product particle size and morphology deviation caused by unstable powder feeding, and helping to improve the production stability and the qualified rate of finished products. Then, the pipe body is extended outward and the powder carrying gas flow outlet is arranged, so as to realize the conveying of the powder carrying gas flow to the subsequent spheroidization process. At the same time, the pipe body penetrates the cavity along the upper axis of the cavity, so that the pipe body is located at the center of the cavity, which helps to reduce the local accumulation or sparseness of the powder in the pipe body during the process of the powder carrying gas flow entering the pipe body from the powder carrying gas flow inlet, effectively reduces the problems such as particle breakage and incomplete spheroidization of the spherical silicon micro-powder caused by uneven powder feeding. Therefore, the powder feeding system for preparing spherical silicon micro-powder provided by the present disclosure can help to reduce the waste rate caused by the defects of the powder feeding link in the preparation of the spherical silicon micro-powder, and improve the product quality. BRIEF DESCRIPTION OF DRAWINGS

[0015] The above and other objects, features and advantages of the present disclosure will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which:

[0016] Figure 1 A cross-sectional view of a powder feeding system for preparing spherical silicon micropowder according to an embodiment of the present disclosure is schematically shown;

[0017] Figure 2 A structural schematic view of an energizing assembly according to an embodiment of the present disclosure is schematically shown.

[0018] In the drawings, the meaning of the reference signs is as follows:

[0019] 1 - powder feeder; 2 - vibration vibrator; 3 - tank body; 4 - energizing assembly; 5 - gas inlet; 6 - gas overflow; 7 - upper cavity; 8 - lower cavity; 9 - through hole; 10 - screen; 11 - pipe body; 12 - high-voltage variable power supply; 13 - tungsten needle; 14 - electrode. DETAILED DESCRIPTION

[0020] In order to make the objects, technical solutions and advantages of the present disclosure clearer, the following will further describe the present disclosure with reference to specific embodiments and drawings.

[0021] The terms used herein are merely used to describe specific embodiments, and are not intended to limit the present disclosure. The terms "include", "comprise" and the like used herein indicate the presence of the features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0022] All terms used herein, including technical and scientific terms, have the meanings commonly understood by one of ordinary skill in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having meanings consistent with the context of the present specification, and should not be interpreted in an idealized or overly formal manner.

[0023] In the case of using expressions similar to "at least one of A, B and C, etc.", it should be generally interpreted that the meaning as understood by one of ordinary skill in the art in general, for example, "a system having at least one of A, B, and C" should include but not be limited to a system having A alone, a system having B alone, a system having C alone, a system having both A and B, a system having both A and C, a system having both B and C, and / or a system having A, B, and C, etc. In the case of using expressions similar to "at least one of A, B, or C, etc.", it should be generally interpreted that the meaning as understood by one of ordinary skill in the art in general, for example, "a system having at least one of A, B, or C" should include but not be limited to a system having A alone, a system having B alone, a system having C alone, a system having both A and B, a system having both A and C, a system having both B and C, and / or a system having A, B, and C, etc.

[0024] It should be noted that the directional terms mentioned in the embodiments, such as "up", "down", "front", "back", "left", "right", etc., are only the directions of the drawings and are not intended to limit the protection scope of the present disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. When it may cause confusion to the understanding of the present disclosure, the conventional structures or configurations will be omitted.

[0025] Figure 1 A cross-sectional view of a powder feeding system for preparing spherical silicon micro-powder according to an embodiment of the present disclosure is schematically shown.

[0026] As shown in Figure 1 The present disclosure provides a powder feeding system for preparing spherical silicon micro-powder, which comprises a powder feeder 1, a tank 3, and a tube 11. The powder feeder 1 comprises a cavity, and a through hole 9 for passing a first gas flow is arranged at the lower part of the side wall of the cavity. The tank 3 is inverted and the tank opening is in communication with the upper end of the cavity for supplying silicon micro-powder raw materials to the cavity. The tube 11 penetrates the cavity along the upper axis of the cavity and extends outward, and the tube 11 is provided with a powder-carrying gas flow inlet and a powder-carrying gas flow outlet.

[0027] Specifically, the powder feeder 1, the tank 3, and the tube 11 are made of stainless steel, but are not limited thereto, to avoid chemical reaction with the silicon micro-powder or generate wear impurities. The overall shape of the powder feeder 1 includes but is not limited to a rectangular parallelepiped. The cavity is arranged inside the powder feeder 1 and includes but is not limited to a cylindrical shape. The extension direction of the through hole 9 is perpendicular to the extension direction of the cavity, and the cross-sectional shape of the through hole 9 includes but is not limited to a circular shape. The first gas flow enters the inside of the cavity along the extension direction of the through hole 9. The opening size of the through hole 9 is adapted to the flow rate of the first gas flow.

[0028] The tank 3 is a storage container for silicon micro-powder raw materials, and the tank opening and the upper end of the cavity are connected by a flange seal, but are not limited thereto, to prevent leakage of silicon micro-powder raw materials or external air from entering and being contaminated. The volume of the tank 3 is adapted to the powder feeding amount of the subsequent spheroidization production line.

[0029] The cross section of the tube 11 includes but is not limited to a cylindrical shape. The extension direction of the tube 11 is perpendicular to the extension direction of the cavity, and the tube 11 penetrates the cavity and is close to the tank opening of the tank 3. Among them, the powder-carrying gas flow inlet on the tube 11 is located inside the cavity; the powder-carrying gas flow outlet is located outside the cavity for subsequent powder feeding of the spheroidization production line.

[0030] The first gas flow is a gas flow that presents a state of violent disturbance and uniform rolling similar to the boiling of a liquid, and the medium of the first gas flow includes but is not limited to using inert gases such as argon and nitrogen. Among them, the inert gas can isolate oxygen to avoid damage to the purity of the raw materials.

[0031] In such an embodiment, firstly, after the first gas flow is introduced into the cavity from the through hole 9 at the lower part of the side wall of the powder feeder 1, an upward gas flow field can be formed in the cavity, which uniformly disturbs the silicon micro-powder raw material supplied by the tank 3, breaks the molecular attraction between the particles of the silicon micro-powder raw material, reduces the agglomeration of the silicon micro-powder raw material, and forms a powder-carrying gas flow together with the silicon micro-powder raw material. The particles of the silicon micro-powder raw material dispersed in the powder-carrying gas flow are more uniformly distributed, which helps to improve the uniformity of the heating of the raw material particles in the subsequent spheroidization process and to help improve the uniformity of the spheroidization degree of the spherical silicon micro-powder. Secondly, the tank 3 is inverted and the tank opening is in communication with the upper end of the cavity, and the silicon micro-powder raw material can be naturally caused to fall downward into the cavity by relying on the action of gravity, thereby realizing stable and continuous powder feeding to the cavity, reducing the interruption of the production of spherical silicon micro-powder or the deviation of the particle size and morphology of the product caused by unstable powder feeding, and helping to improve the production stability and the qualified rate of the finished product. Then, the powder-carrying gas flow is transported to the subsequent spheroidization process by extending the pipe body 11 outward and providing a powder-carrying gas flow output port, and the pipe body 11 penetrates the cavity along the axis of the upper part of the cavity, so that the pipe body 11 is located at the center of symmetry in the cavity, which helps to reduce the local accumulation or sparseness of the powder in the pipe body 11 during the process of the powder-carrying gas flow entering the pipe body 11 from the powder-carrying gas flow input port, and effectively reduces the problems of particle breakage and incomplete spheroidization of the spherical silicon micro-powder caused by uneven powder feeding. Therefore, the powder feeding system for preparing spherical silicon micro-powder provided by the present disclosure can help to reduce the waste rate caused by defects in the powder feeding link during the preparation of spherical silicon micro-powder, and improve the product quality.

[0032] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon micro-powder further comprises a gas inlet port 5. The gas inlet port 5 is arranged on the upper part of the side wall of the tank 3 and is away from the tank opening, and is used to introduce a second gas flow into the tank 3. The powder feeding system for preparing spherical silicon micro-powder further comprises a gas overflow port 6. The gas overflow port 6 is arranged on the side wall of the tank 3 and is on the same side of the tank 3 as the gas inlet port 5.

[0033] Specifically, the extension direction of the gas inlet port 5 is perpendicular to the extension direction of the tank 3, and the cross-sectional shape of the gas inlet port 5 includes but is not limited to a circular ring shape. One open end surface of the gas inlet port 5 covers the opening on the side wall of the tank 3. The opening size of the gas inlet port 5 and the opening on the side wall of the tank 3 is adapted to the flow rate of the second gas flow. The gas overflow port 6 includes but is not limited to a circular hole arranged on the side wall of the tank 3. The size of the gas overflow port 6 is adapted to the opening size of the gas inlet port 5 and the opening on the side wall of the tank 3, for example, the diameter of the gas overflow port 6 is set to be 0.5 to 2 times the inner diameter of the gas inlet port 5.

[0034] Further, the second gas flow enters the inside of the tank 3 from the other open end surface of the gas inlet port 5 along the extension direction of the gas inlet port 5, so that the gas pressure in the tank 3 continuously increases, and part of the second gas flow is discharged from the tank 3 through the gas overflow port 6. Wherein, the second gas flow and the first gas flow include but are not limited to using the same gas flow.

[0035] In such an embodiment, on the one hand, the second gas flow enters the inside of the tank body 3 through the gas inlet 5, forms disturbance to the silicon powder raw material in the tank body 3, helps to break the silicon powder raw material agglomeration, at the same time, pushes the silicon powder raw material to move towards the tank opening, helps to avoid the tank opening blockage, is beneficial to prevent the powder supply interruption problem, and promotes the silicon powder raw material to continuously and smoothly enter the cavity, which is beneficial to maintain the mixing effect of the powder-carrying gas flow. On the other hand, the excess second gas flow in the tank body 3 is discharged in time through the gas overflow port 6, which helps to balance the pressure in the tank body 3, and is beneficial to prevent the silicon powder raw material from falling too fast or the sealing element of the tank body 3 from being damaged due to the excessive gas pressure in the tank body 3. In addition, the gas overflow port 6 and the gas inlet 5 are located on the same side of the tank body 3, which reduces the vortex of the second gas flow in the tank body 3, improves the uniformity of the gas pressure distribution, and is beneficial to realize the continuous and stable powder supply of the tank body 3 to the cavity, auxiliary to improve the continuity and stability of the powder-carrying gas flow generation and conveying process, and promote the production efficiency of the subsequent spherical silicon powder.

[0036] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon powder further comprises a vibration vibrator 2. The vibration vibrator 2 is connected to the powder feeder 1, and the vibration vibrator 2 is connected with a motor with a fixed frequency output.

[0037] Specifically, the vibration vibrator 2 includes but is not limited to being fixed on the bottom or lower part of the side wall of the powder feeder 1 by bolts, and the output frequency of the motor is set according to the particle size of the silicon powder raw material, including but not limited to 50-200Hz. The vibration vibrator 2 is driven to vibrate by the motor, which drives the powder feeder 1, the tank body 3 and the pipe body 11 to vibrate together. Wherein, the fixed position of the vibration vibrator 2 avoids the through hole 9, preventing the vibration from affecting the stable input of the first gas flow.

[0038] In such an embodiment, on the one hand, the vibration vibrator 2 vibrates at a fixed frequency, which can effectively destroy the van der Waals force between the silicon powder raw material particles, and promote the reduction of silicon powder raw material agglomeration. On the other hand, the disturbance of the first gas flow and the vibration vibrator 2 produce a synergistic effect, which further improves the uniformity of the silicon powder raw material dispersion, is beneficial to improve the mixing effect of the powder-carrying gas flow, and helps to improve the uniformity of the silicon powder raw material particles heated during the subsequent spheroidization process, so as to promote the uniformity of the spheroidization degree of the spherical silicon powder.

[0039] According to some embodiments of the present disclosure, the powder-carrying gas flow inlet and the powder-carrying gas flow outlet are each provided with a one-way valve for isolating the communication between the pipe body 11 and the cavity.

[0040] Specifically, the one-way valve includes but is not limited to using a spring check valve structure, the one-way valve of the powder carrying gas inlet port only allows the powder carrying gas to enter the pipe body 11, and the one-way valve of the powder carrying gas outlet port only allows the powder carrying gas to output from the pipe body 11 to the subsequent process. The opening pressure of the one-way valve is adapted to the pressure of the powder carrying gas, which is opened when the powder carrying gas flows through, and is quickly closed under the action of the spring force when the powder carrying gas is interrupted.

[0041] Further, the one-way valve uses a wear-resistant and corrosion-resistant material, such as polytetrafluoroethylene or 316L stainless steel, to prevent the sealing from being damaged by long-term erosion of silicon powder. The one-way valve and the pipe body 11 are connected by threads, which are convenient for disassembly, maintenance or replacement. The fluororubber gasket is arranged between the valve core and the valve seat of the one-way valve to enhance the sealing performance.

[0042] In such an embodiment, on the one hand, the powder carrying gas enters the inside of the pipe body 11 through the one-way valve of the powder carrying gas inlet port, and the reverse communication between the pipe body 11 and the cavity is blocked by the one-way valve, which reduces the reflow of the powder carrying gas and causes the reoccurrence of the powder agglomeration, and helps to maintain the stability of the process of mixing the first gas flow in the upper part of the cavity with the silicon powder raw material to form the powder carrying gas. On the other hand, when the one-way valve of the powder carrying gas outlet port is opened, the powder carrying gas flows out along the extension direction of the pipe body 11 into the subsequent device for preparing spherical silicon powder, and by closing the one-way valve, the reverse flow of external air or high-temperature gas from the subsequent device into the inside of the pipe body 11 is timely blocked, which helps to reduce the adverse effects of external pollution and high-temperature impact on the powder feeding process and the purity or morphology of the silicon powder raw material, and promotes the powder feeding system to continuously provide high-quality raw materials for the production process of preparing spherical silicon powder.

[0043] Figure 2 The structure of the power supply assembly according to the embodiment of the present disclosure is schematically shown.

[0044] As Figure 2 shown, the powder feeding system for preparing spherical silicon powder further includes a power supply assembly 4. The power supply assembly 4 is arranged at the powder carrying gas outlet port and is used for making the silicon powder raw material flowing therethrough have the same charge. The power supply assembly 4 includes an electrode 14 and a high-voltage transformer power supply 12. The electrode 14 is in the form of a plate, and a surface thereof is arranged with tungsten needles 13. The electrode 14 is connected to the high-voltage transformer power supply 12, so that the tungsten needles 13 can be discharged. The tungsten needles 13 are symmetrically arranged in at least two rows on the electrode 14, and each row of the tungsten needles 13 is arranged in the form of equal spacing.

[0045] Specifically, the high-voltage variable power supply 12 outputs a direct-current high voltage, and the voltage range includes but is not limited to 10-50kV. The electrode 14 includes but is not limited to being arranged in the shape of a cuboid, and the surface of the electrode 14 is wrapped around the powder-carrying gas flow output port provided with the tungsten needle 13, so that the powder-carrying gas flow can flow through the electric field generated by the tungsten needle 13 after flowing out of the powder-carrying gas flow output port. The electrode 14 includes but is not limited to being made of 304 stainless steel, and the surface of the electrode 14 is polished to reduce the adhesion of the powder.

[0046] The diameter of the tungsten needle 13 includes but is not limited to being 0.5-2mm, and the tip of the tungsten needle 13 is sharpened to enhance the strength of the electric field. The tungsten needle 13 and the electrode 14 are fixed by welding to prevent the tungsten needle 13 from falling off during discharge.

[0047] In addition, a metal protective shell connected to the ground is arranged outside the power-on assembly 4 to prevent the operator from accidentally touching the high-voltage components.

[0048] In such an embodiment, by arranging the electrode 14 with the tungsten needle 13 at the powder-carrying gas flow output port and using the high-voltage variable power supply 12 to make the tungsten needle 13 discharge, single-polarity ions (such as positive ions) are generated in the gas around the tungsten needle 13 to form an electric field, and the silicon micro-powder raw material in the powder-carrying gas flow adsorbs ions when flowing through the electric field, and is uniformly charged. The Coulomb repulsion generated by the same charge can effectively reduce the agglomeration of the powder in the conveying process due to the intermolecular force, and maintain the dispersed state of the powder. The symmetric arrangement of the tungsten needles 13 and the formation of an array with equal spacing facilitate the formation of a uniformly distributed electric field on the surface of the electrode 14, reduce the local electric field that is too strong to cause the powder to break down or too weak to cause the powder to be unevenly charged, and at the same time, improve the consistency of the charge of each powder, reduce the local accumulation of the powder caused by uneven charging, and facilitate the maintenance of the integrity and uniform dispersion of the silicon micro-powder raw material entering the spheroidization process, and promote the improvement of the spheroidization quality and consistency of the spherical silicon micro-powder.

[0049] According to some embodiments of the present disclosure, the powder feeding system for preparing spherical silicon micro-powder further comprises a screen 10. The screen 10 is arranged inside the cavity and divides the cavity into an upper cavity 7 and a lower cavity 8. The aperture of the screen 10 is smaller than the particle size of the silicon micro-powder raw material, and is used to block the silicon micro-powder raw material from entering the lower cavity 8.

[0050] Specifically, the screen 10 is horizontally arranged in the middle of the cavity to divide the cavity into an upper cavity 7 and a lower cavity 8. The screen 10 includes but is not limited to being made of stainless steel, which has the characteristics of high temperature resistance and wear resistance. The aperture of the screen 10 includes but is not limited to being set to be 10-20μm smaller than the minimum particle size of the silicon micro-powder raw material. For example, when the particle size of the silicon micro-powder raw material is 100-200μm, the aperture of the screen 10 is 80-90μm, so that the silicon micro-powder raw material cannot pass through the screen 10 to enter the lower cavity 8.

[0051] Further, including but not limited to setting a ring-shaped metal frame at the edge of the screen 10, the frame is connected with the inner wall of the cavity by a clamping groove, which facilitates the disassembly and cleaning or replacement of the screen 10.

[0052] In addition, the opening rate of the screen 10 includes but is not limited to 30% to 70%, which not only ensures the smooth passage of the first airflow, but also makes the first airflow diffuse more uniformly through the throttling effect.

[0053] In such an embodiment, by setting a screen 10 with a smaller pore size than the silicon powder raw material in the cavity, the upper cavity 7 and the lower cavity 8 are separated, the screen 10 blocks the silicon powder raw material from entering the lower cavity 8, helps to avoid the silicon powder raw material from blocking the through hole 9 of the lower cavity 8, promotes the stable passage of the first airflow, and helps to reduce the occurrence of powder feeding interruption caused by the blockage of the through hole 9. At the same time, the first airflow is uniformly diffused to the upper cavity 7 after throttling through the screen 10, which improves the dispersion of the silicon powder raw material and the mixing effect with the first airflow, which is beneficial to provide a powder-carrying airflow with uniform airflow and dispersed powder for subsequent processes, and is beneficial to reduce the waste rate caused by process defects of the cavity and promote the quality improvement of the subsequently produced spherical silicon powder.

[0054] According to some embodiments of the present disclosure, the powder-carrying airflow input port is arranged on the middle side of the pipe body 11, and the powder-carrying airflow output port is arranged on the side of the pipe body 11 close to the end.

[0055] Specifically, the powder-carrying airflow input port is arranged on the middle side of the pipe body 11 that penetrates the cavity, which is in a region where the airflow and the silicon powder raw material are mixed uniformly in the cavity. The shape of the powder-carrying airflow input port includes but is not limited to a circular shape, and the pore size includes but is not limited to 1 / 3 to 1 / 2 of the diameter of the pipe body 11. The powder-carrying airflow output port is arranged on the side close to the end of the pipe body 11 that extends out of the cavity and enters the feed port of the subsequent spheroidization process equipment, reducing the loss of the powder-carrying airflow during transportation.

[0056] In such an embodiment, by arranging the powder-carrying airflow input port on the middle side of the pipe body 11, the powder-carrying airflow can efficiently carry the surrounding dispersed silicon powder raw material. At the same time, the powder-carrying airflow output port is arranged close to the end, reducing airflow resistance and powder accumulation, and promoting the efficient transportation of the powder-carrying airflow to the subsequent process. Therefore, it is beneficial to provide protection for the continuous spheroidization processing of spherical silicon powder and reduce production delays caused by low transportation efficiency.

[0057] The above describes embodiments of the present disclosure. However, these embodiments are merely for illustrative purposes, and are not intended to limit the scope of the present disclosure. Although each embodiment is described above separately, this does not mean that the measures in each embodiment cannot be used advantageously in combination. The scope of the present disclosure is defined by the appended claims and their equivalents. Those skilled in the art can make various substitutions and modifications without departing from the scope of the present disclosure, and these substitutions and modifications should all fall within the scope of the present disclosure.

Claims

1. A powder feeding system for preparing spherical silicon fine powder, characterized by comprising: The device comprises: a powder feeder (1) comprising a cavity, a lower part of the cavity wall being provided with a through hole (9) for the first gas flow; a tank (3) inverted and having an opening communicating with the upper end of the cavity for supplying the cavity with silicon powder raw material; a tube (11) penetrating the cavity along the upper axis of the cavity and extending outward, the tube (11) being provided with a powder-carrying gas inlet and a powder-carrying gas outlet.

2. The powder feeding system for producing spherical silicon fine powder according to claim 1, wherein Further comprising: a gas inlet (5) provided on the upper part of the side wall of the tank (3) and away from the opening of the tank for the second gas flow into the tank (3).

3. The powder feeding system for producing spherical silicon fine powder according to claim 2, wherein Further comprising: a gas overflow port (6) provided on the side wall of the tank (3) and on the same side of the tank (3) as the gas inlet (5).

4. The powder feeding system for producing spherical silicon fine powder according to claim 1, wherein Further comprising: a vibration vibrator (2) connected to the powder feeder (1), the vibration vibrator (2) being connected to an output fixed frequency motor.

5. The powder feeding system for preparing spherical silicon fine powder according to claim 1, wherein The powder-carrying gas inlet and the powder-carrying gas outlet are both provided with a one-way valve for isolating the tube (11) from the cavity.

6. The powder feeding system for preparing spherical silicon fine powder according to claim 1, wherein Further comprising: a power supply assembly (4) provided at the powder-carrying gas outlet for making the silicon powder raw material flowing through the same charge.

7. The powder feeding system for producing spherical silicon fine powder according to claim 6, wherein The power supply assembly (4) comprises an electrode (14) and a high-voltage variable power supply (12). The electrode (14) is plate-shaped and has tungsten needles (13) arranged on the surface. The electrode (14) is connected to the high-voltage variable power supply (12) to make the tungsten needles (13) discharge.

8. The powder feeding system for producing spherical silicon fine powder according to claim 7, wherein The tungsten needles (13) are symmetrically arranged in at least two rows on the electrode (14), and each row of the tungsten needles (13) is arranged at equal intervals.

9. The powder feeding system for preparing spherical silicon fine powder according to claim 1, wherein Further comprising: a screen (10) provided inside the cavity and separating the cavity into an upper cavity (7) and a lower cavity (8), the screen (10) having a pore size smaller than the particle size of the silicon powder raw material for blocking the silicon powder raw material from entering the lower cavity (8).

10. The powder feeding system for producing spherical silicon fine powder according to claim 1, wherein The powder-carrying gas inlet is provided on the middle side of the tube (11), and the powder-carrying gas outlet is provided on the side of the tube (11) near the end.

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