Electrostatic separation apparatus and method for germanium-containing dust

Abstract

The application discloses a kind of germanium-containing dust electrostatic separation device and method thereof, belong to germanium production technical field.It includes charging chamber, separation chamber, scraper device and negative pressure impurity removal area.Charging chamber makes dust charge;Deflection plate and opposite plate are provided in separation chamber, utilize the difference on charge retention ability of germanium and insulating impurities, so that insulating impurities are adsorbed on deflection plate, and germanium powder is settled and collected due to charge leakage;Scraper device pushes impurities from below to above along the surface of deflection plate;Negative pressure impurity removal area is arranged at the top of separation chamber, is isolated from main airflow by partition, and is negative pressure suction and discharged when impurities are pushed by scraper.The application realizes efficient separation of germanium powder and impurities, and the purity of recovered germanium powder is high, which can be directly reused, and there is no secondary dust raising in the dust cleaning process, and long-term operation is stable.

Description

Technical Field

[0001] This application relates to the field of germanium material production technology, and specifically to an electrostatic separation device and method for germanium-containing dust in the germanium pretreatment and conveying process. Background Technology

[0002] In the pretreatment of high-value semiconductor materials such as germanium, dried germanium particles generate a large amount of fine dust during vibration conveying and airflow sorting. Because germanium is a brittle material, the particles inevitably collide with each other and rub against the equipment walls during conveying, producing a large amount of fine germanium powder with a particle size of less than 10 μm. Simultaneously, impurities such as organic matter and oxides contained in the crude germanium raw material are also mixed into the dust-laden airflow as fine dust. During the conveying process after drying, the surface of the germanium particles loses moisture, reducing adhesion and allowing the fine dust to easily detach and disperse, causing not only direct loss of valuable materials (up to 1%-3%) but also polluting the sorting environment and reducing the efficiency of subsequent sorting equipment. Therefore, how to efficiently collect dust during conveying and separate valuable germanium powder from worthless impurity dust to achieve high-purity germanium powder recovery has long been a technical challenge in this field.

[0003] In existing technologies, dust collection during transportation typically employs a combination of closed-loop negative pressure air collection and bag filters or HEPA filters. While this approach achieves a high dust collection rate, it suffers from a fundamental flaw: bag filters are particle size selective, meaning they don't differentiate between dust particles of varying sizes; any sufficiently small particle will be captured. Consequently, the recovered "dust mixture" often contains germanium powder mixed with organic matter, oxides, and other impurities, with the germanium content frequently below 50%. Directly reusing this mixed dust in the process would reintroduce a large amount of impurities, causing cumulative pollution. Separating the components requires additional acid washing and sorting processes, which are costly. Therefore, existing solutions essentially only address the "dust collection" problem.

[0004] Dual-zone electrostatic precipitators are another type of known dust separation equipment. They typically include a charging chamber and a collection zone. Dust particles are charged in the charging chamber and then attracted to the collecting plates by an electric field in the collection zone. They are then removed by rapping and fall into the bottom ash hopper. For example, CN101670311B discloses a dual-zone multi-stage electrostatic precipitator for reverse-flow dust charging, which improves dust charging efficiency through a specific structure of the grid anode and grid tube cathode. However, the design goal of this type of equipment is still "dust removal"—removing as much dust as possible from the airflow, without distinguishing dust components. Its collection zone uses a traditional plate dust collection mode, with cleaning primarily done by rapping or gravity dropping. The scraped dust falls directly into the bottom ash hopper and mixes with other impurities. This crude recovery mode is acceptable in general industrial dust removal, but it would cause incalculable losses if used for the recovery of high-value germanium dust. Meanwhile, the rapping method for dust removal has a significant problem of secondary dust generation, as the fallen dust is easily carried back by the airflow, further reducing the separation effect. Summary of the Invention

[0005] This application provides an electrostatic separation device for germanium-containing dust to solve the problem of difficult recovery of germanium dust and waste of resources in the prior art.

[0006] To achieve the above objectives, this application provides the following technical solution: In one embodiment, this application provides an electrostatic separation device for germanium-containing dust, comprising: The charging chamber 100 is equipped with a corona electrode 101 for charging dust particles in the germanium-containing dust airflow. The separation chamber 200 is connected to the charging chamber 100 at its top. A deflection plate 201 and a counter plate 202 are provided in the separation chamber 200. A vertical airflow channel is formed between the deflection plate 201 and the counter plate 202. The deflection plate 201 is connected to a high-voltage power supply to adsorb the insulating impurities after charging. A collection hopper 204 for collecting germanium particles is provided at the bottom of the separation chamber 200. A scraper device 400, disposed in the lower part of the separation chamber 200, includes a scraper 403 and a drive mechanism. The scraper 403, under the action of the drive mechanism, moves upward along the surface of the deflection plate 201, pushing impurities adsorbed on the deflection plate 201 upward. The negative pressure impurity removal zone 300 is located at the top of the separation chamber 200 and above the deflection plate 201. The negative pressure impurity removal zone 300 is separated from the separation chamber 200 by a partition 301. A gap is left between the lower end of the partition 301 and the top end of the deflection plate 201 to form a dust collection inlet 3031. The negative pressure impurity removal zone 300 is connected to a negative pressure source, which is used to suck away the impurities when the scraper 403 pushes the impurities into the negative pressure impurity removal zone 300 through the dust collection inlet 3031.

[0007] In an alternative embodiment, the scraper device 400 further includes: The bracket 401 and the electric push rod 402 are fixed to the bottom of the outer shell of the separation chamber 200. The electric push rod 402 is mounted on the bracket 401. The telescopic end of the electric push rod 402 extends into the separation chamber 200 and is connected to the scraper 403 to drive the scraper 403 to rise and fall.

[0008] In one alternative, the separator 301 has a sheet-like extension 3011 extending toward the deflection plate 201, and a dust collection inlet 3031 is formed between the end of the extension 3011 and the top of the deflection plate 201.

[0009] In one alternative, the separator 301 is provided with an elastic sealing body 3012, which is located on the side of the extension 3011 facing the deflection plate 201. The extension 3011, the elastic sealing body 3012 and the top of the deflection plate 201 directly enclose the dust collection inlet 3031. When the scraper 403 pushes the impurities to the dust collection inlet 3031, the scraper 403 abuts against the elastic sealing body 3012, thereby temporarily isolating the airflow channel of the negative pressure impurity removal zone 300 from the separation chamber 200.

[0010] In one alternative embodiment, the negative pressure impurity removal zone 300 includes a dust collection chamber 303 formed by the enclosure of a separator 301, the upper end of a deflection plate 201, and part of the inner wall of the separation chamber 200, and a dust collection hood 302 disposed on one side of the dust collection chamber 303. The dust collection hood 302 has a dust collection chamber 3021 inside that communicates with the dust collection chamber 303, and the dust collection chamber 3021 is connected to the negative pressure source.

[0011] In one alternative configuration, the charging chamber 100 and the separation chamber 200 are arranged in a stacked structure, with the bottom end of the charging chamber 100 and the top end of the separation chamber 200 directly connected by a connecting straight pipe 203.

[0012] In one alternative, a removable perforated flow equalization plate 2031 is provided at one end of the connecting straight pipe 203 near the separation chamber 200; the internal space of the connecting straight pipe 203 above the perforated flow equalization plate 2031 forms a pre-settling zone 2032, and the perforation rate of the perforated flow equalization plate 2031 is 30% to 50%, and the aperture is 5mm to 10mm, which is used to evenly distribute the pre-settled airflow before sending it into the separation chamber 200.

[0013] In one alternative, the corona electrode 101 of the charged chamber 100 is connected to a pulsed high-voltage power supply, which outputs a negative polarity pulse voltage with a pulse width of 50μs to 200μs, a pulse frequency of 50Hz to 500Hz, and a peak voltage of -20kV to -30kV.

[0014] In an alternative embodiment, the germanium-containing dust electrostatic separation device of this application further includes: The cyclone separator and the blower are connected. The inlet of the cyclone separator is connected to multiple dust collection points above the closed vibrating conveyor trough for dried germanium particles. The gas outlet of the cyclone separator is connected to the blower, and the outlet of the blower is connected to the inlet of the charging chamber 100. The bottom discharge port of the cyclone separator is connected to the closed vibrating conveyor trough to send back the pre-separated large particles.

[0015] In one alternative, during the process of the drive mechanism driving the scraper 403 to push impurities upward and return to downward movement, residual impurities that fall from the scraper 403 or the dust collection inlet 3031 are re-adsorbed onto the surface of the deflection plate 201 under the action of the electric field of the deflection plate 201, ready for the next push.

[0016] In an alternative embodiment, the bottom of the collecting hopper 204 is provided with an airlock discharge valve for discharging the collected germanium particles while maintaining a sealed state.

[0017] In another embodiment, this application provides a method for electrostatic separation of germanium-containing dust applied to the aforementioned electrostatic separation device for germanium-containing dust, comprising the following steps: Step 1: Introduce the airflow containing germanium dust into the charging chamber 100, and charge the dust particles by discharging through the corona electrode 101. Step 2: The charged airflow is introduced into the separation chamber 200. In the vertical electric field between the deflection plate 201 and the counter plate 202, the difference in charge retention ability between germanium dust and insulating impurities is utilized to cause the insulating impurities to be adsorbed on the surface of the deflection plate 201, while the germanium dust, due to charge leakage, is not affected by the electric field force and falls into the collection hopper 204 under the action of gravity for collection. Step 3: When the impurities adsorbed on the surface of the deflection plate 201 accumulate to a set level, drive the scraper 403 to move from bottom to top along the surface of the deflection plate 201, pushing the impurities to the dust collection inlet 3031 at the top of the deflection plate 201. The beneficial effects of this application are: Selective separation improves germanium recovery purity: Utilizing the difference in charge retention capabilities between germanium and insulating impurities in an electric field, germanium powder is recovered through sedimentation while impurities are selectively adsorbed. Germanium powder, due to rapid charge leakage, is unaffected by the electric field and falls directly into the collection hopper; insulating impurities are adsorbed by deflection plates and discharged by scrapers, improving the purity and efficiency of germanium recovery from dust. The recovered material can be directly reused in the process flow without secondary purification.

[0018] A specially designed impurity removal structure prevents secondary dust generation: the scraper pushes impurities from bottom to top to the negative pressure impurity removal zone at the top of the separation chamber. Once pushed into the negative pressure zone, isolated from the main airflow, the impurities are immediately sucked away, preventing them from being re-carried by the airflow. This ensures a clean and efficient dust removal process. Furthermore, it features a self-healing mechanism; any residual impurities that may fall off during the scraper's return will fall back into the electric field area of ​​the deflector plate, be re-adsorbed, and discharged in the next push. This further improves the purity and impurity removal efficiency of the germanium dust recovery, ensuring the system's reliability and stability during long-term operation.

[0019] Pre-settling and uniform airflow distribution enhance separation efficiency: A pre-settling zone and a porous flow equalizer are installed between the charging chamber and the separation chamber, allowing large germanium particles to settle in advance and reducing the load on the separation chamber. The airflow is evenly distributed through the flow equalizer before entering the electric field region, preventing a decrease in separation efficiency caused by uneven local flow rates. Furthermore, the porous flow equalizer uses a removable installation method, and the components of the negative pressure impurity removal zone are easy to disassemble and assemble. The scraper drive mechanism is externally mounted, eliminating the need to open the separation chamber for maintenance, making maintenance convenient and operation simple. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure in one embodiment of this application; Figure 2 This is a schematic diagram of the connection structure between the charging chamber and the separation chamber in one embodiment of this application; Figure 3 This is a schematic diagram of the separation chamber, scraper device, and negative pressure impurity removal zone in one embodiment of this application. Figure 4 This is a partially enlarged structural diagram of the negative pressure impurity removal zone in one embodiment of this application; Labels for each item in the figure: 100. Charging chamber; 101. Corona electrode; 200. Separation chamber; 201. Deflection plate; 202. Counter plate; 203. Connecting straight pipe; 2031. Porous flow equalization plate; 2032. Pre-settling zone; 204. Collection hopper; 300. Negative pressure cleaning zone; 301. Separator; 3011. Extension; 3012. Elastic sealing body; 302. Dust hood; 3021. Dust suction chamber; 303. Dust collection chamber; 3031. Dust collection inlet; 400. Scraper device; 401. Bracket; 402. Electric push rod; 403. Scraper; a, b, and c are examples of the layout of dust collection points on the vibrating conveyor trough. Detailed Implementation

[0022] The specific embodiments of this application will be further described in detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but are not intended to limit the scope of this application. Similarly, the following examples are only some embodiments of this application, not all embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] In the description of this application, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0024] In this application, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between the components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0025] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0026] In some implementations, please refer to Figures 1 to 4 This application provides an electrostatic separation device for germanium-containing dust, comprising: a charging chamber 100, a separation chamber 200, a scraper device 400, and a negative pressure impurity removal zone 300.

[0027] A corona electrode 101 is installed inside the charging chamber 100 to charge dust particles in the germanium-containing dust airflow. The top of the separation chamber 200 is connected to the charging chamber 100. A deflection plate 201 and a counter plate 202 are installed inside the separation chamber 200, forming a vertical airflow channel between the deflection plate 201 and the counter plate 202. The deflection plate 201 is connected to a high-voltage power supply (usually positive high voltage, such as +5kV to +10kV) to adsorb charged insulating impurities. A collection hopper 204 for collecting germanium particles is installed at the bottom of the separation chamber 200.

[0028] The scraper device 400 is located at the lower part of the separation chamber 200 and includes a scraper 403 and a drive mechanism. The scraper 403 can move upward along the surface of the deflection plate 201 under the action of the drive mechanism, pushing the impurities adsorbed on the deflection plate 201 upward.

[0029] The negative pressure impurity removal zone 300 is located at the top of the separation chamber 200 and above the deflection plate 201. The negative pressure impurity removal zone 300 is separated from the separation chamber 200 by a partition 301, with a gap between the lower end of the partition 301 and the top end of the deflection plate 201 to form a dust collection inlet 3031. The negative pressure impurity removal zone 300 is connected to a negative pressure source (e.g., a vacuum pump) to suck away impurities when the scraper 403 pushes them into the negative pressure impurity removal zone 300 through the dust collection inlet 3031.

[0030] This embodiment provides a core structure capable of selectively separating germanium-containing dust. It utilizes the difference in charge retention capacity between germanium (semiconductor) and insulating impurities (high resistivity) in an electric field, causing the insulating impurities to be adsorbed by the deflection plate 201, while the germanium powder settles due to rapid charge leakage; at the same time, the impurities are directionally discharged by a combination of an upward-pushing scraper 403 and top negative pressure suction, avoiding secondary dust generation.

[0031] During operation, the dust-laden airflow first enters the charging chamber 100, where dust particles (including germanium powder and insulating impurities) acquire a negative charge under the corona discharge of the corona electrode 101. The airflow then enters the separation chamber 200. In the transverse electric field formed by the deflection plate 201 and the counter plate 202, insulating impurities are adsorbed onto the surface of the deflection plate 201 because their charge is difficult to leak out. The germanium powder loses its charge due to rapid leakage to the counter plate 202 and is unaffected by the electric field, falling to the collection hopper 204 under gravity. When impurities accumulate on the surface of the deflection plate 201, the scraper 403 pushes the impurities upwards to the dust collection inlet 3031 at the top. The negative pressure source draws the impurities into the negative pressure impurity removal zone 300 and discharges them. This achieves selective separation of germanium powder and impurities, effectively improving the purity of the recovered germanium powder, allowing for direct reuse. Simultaneously, the dust removal process generates no secondary dust, ensuring stable long-term operation.

[0032] It should be noted that the charging chamber 100 adopts a conventional wire-plate corona charging structure in this field. Specifically, within the charging chamber shell, multiple stainless steel corona wires (0.5 mm in diameter, spaced 30 mm apart) are vertically tensioned along the airflow direction. These corona wires are connected to a negative high-voltage DC power supply (voltage -15 kV to -25 kV). The two side walls of the charging chamber (or a grounding grid plate located in the center of the airflow channel) serve as grounding electrodes and are connected to the positive terminal of the power supply. When the dust-laden airflow passes through the charging chamber, a large number of negative ions generated by the corona discharge adhere to the surface of the dust particles, charging them. This charging method is a well-known technology in the field of electrostatic dust removal and will not be elaborated upon here.

[0033] In some implementations, please refer to Figure 3 The scraper device 400 also includes a bracket 401 and an electric push rod 402. The bracket 401 is fixed to the bottom of the outer shell of the separation chamber 200. The electric push rod 402 is mounted on the bracket 401. The telescopic end of the electric push rod 402 extends into the separation chamber 200 and is connected to the scraper 403 to drive the scraper 403 to rise and fall. The electric push rod 402 extends or retracts under the command of the control system, driving the scraper 403 to move from bottom to top or from top to bottom along the surface of the deflector plate 201. As an example, the upward pushing speed is slower (e.g., 10-30 mm / s) to ensure that impurities are smoothly pushed into the dust collection inlet 3031; the downward return speed is faster (e.g., 50-100 mm / s) to reduce interference with the separation process. In this example, the drive mechanism is externally located in the separation chamber 200 for easy maintenance; the stroke of the electric push rod 402 is precisely controllable and can adapt to the dust removal requirements of different impurity accumulation amounts.

[0034] In some implementations, please refer to Figure 4 The separator 301 has a sheet-like extension 3011 extending towards the deflector plate 201. The end of the extension 3011 forms a dust collection inlet 3031 between itself and the top of the deflector plate 201. Specifically, the extension 3011 extends from the main body of the separator 301 towards the deflector plate 201, with its lower end a certain distance below the top of the deflector plate 201, thus forming the dust collection inlet 3031 between itself and the top of the deflector plate 201. When the scraper 403 pushes impurities to the top of the deflector plate 201, the impurities smoothly enter the dust collection inlet 3031 under the pushing force of the scraper 403 and the guiding action of the extension 3011. The extension 3011, in conjunction with the scraper 403, blocks and isolates the dust collection inlet 3031, reducing the risk of impurities falling back.

[0035] In some implementations, please refer to Figure 4An elastic sealing body 3012 is provided on the separator 301, located on the side of the extension 3011 facing the deflection plate 201. The extension 3011, the elastic sealing body 3012, and the top of the deflection plate 201 directly enclose the dust collection inlet 3031. When the scraper 403 pushes impurities to the dust collection inlet 3031, the scraper 403 abuts against the elastic sealing body 3012, thereby temporarily isolating the airflow channel between the negative pressure impurity removal zone 300 and the separation chamber 200. The elastic sealing body 3012 can be made of materials such as silicone rubber strips or polyurethane strips. When impurities are suctioned under negative pressure, it temporarily cuts off the connection between the negative pressure impurity removal zone 300 and the main airflow channel of the separation chamber 200, preventing negative pressure suction from interfering with the stable flow of the main airflow and avoiding accidental suction of germanium powder.

[0036] In some implementations, please refer to Figure 3 and Figure 4 The negative pressure impurity removal zone 300 includes a dust collection chamber 303 formed by the enclosure of a separator 301, the upper end of a deflector plate 201, and part of the inner wall of the separation chamber 200, and a suction hood 302 disposed on one side of the dust collection chamber 303. The suction hood 302 has a suction chamber 3021 inside that communicates with the dust collection chamber 303, and the suction chamber 3021 is connected to a negative pressure source. This creates a sealed negative pressure space isolated from the main airflow, used to temporarily store impurities pushed in by the scraper 403 and facilitate negative pressure suction. The suction hood 302 can be designed as a detachable structure for easy cleaning and maintenance.

[0037] In some implementations, please refer to Figure 2 and Figure 3 The charging chamber 100 and the separation chamber 200 are arranged in a stacked structure, with the bottom end of the charging chamber 100 and the top end of the separation chamber 200 directly connected by a connecting straight pipe 203. As an example, the connecting straight pipe 203 is made of insulating material or has an insulating coating on its inner wall surface to prevent charge leakage when dust particles come into contact with the grounded surface, and to avoid eddies or uneven airflow distribution at the connection point.

[0038] In some implementations, please refer to Figure 3A removable porous flow equalization plate 2031 is installed at one end of the connecting straight pipe 203 near the separation chamber 200. The internal space of the connecting straight pipe 203 above the porous flow equalization plate 2031 forms a pre-settling zone 2032. The porous flow equalization plate 2031 has an opening ratio of 30% to 50% and a pore diameter of 5 mm to 10 mm, used to evenly distribute the pre-settled airflow before sending it into the separation chamber 200. The porous flow equalization plate 2031 is made of insulating material or has an insulating coating on its surface. Inside the connecting straight pipe 203, due to the increased pipe diameter or reduced airflow velocity (designed to be 0.8 to 1.2 m / s), germanium particles with a diameter greater than 100 μm preferentially settle under gravity and fall directly into the collection hopper 204 at the bottom of the separation chamber 200. The remaining airflow passes through the porous flow equalization plate 2031. The plate evens out the airflow velocity distribution, avoiding excessively high velocity at the center and excessively low velocity at the edges. This allows the airflow to enter the channel between the deflection plate 201 and the counter plate 202 at a uniform velocity, making the electric field more effective at adsorbing impurities and improving separation efficiency.

[0039] In some implementations, please refer to Figure 2 The corona electrode 101 of the charging chamber 100 is connected to a pulsed high-voltage power supply. The pulsed high-voltage power supply outputs a negative polarity pulse voltage with a pulse width of 50μs to 200μs, a pulse frequency of 50Hz to 500Hz, and a peak voltage of -20kV to -30kV. This improves the charging efficiency for submicron-sized fine particles while reducing ozone generation and lowering energy consumption.

[0040] In some implementations, please refer to Figure 1 The electrostatic separation device for germanium-containing dust in this application further includes a cyclone separator and a fan. The inlet of the cyclone separator is connected to multiple dust collection points (e.g., above a closed vibrating conveyor trough for dried germanium particles). Figure 1 Points a, b, and c in the diagram are referenced. The gas outlet of the cyclone separator is connected to a blower, and the blower outlet is connected to the inlet of the charging chamber 100. The bottom discharge port of the cyclone separator is connected to a closed vibrating conveyor trough to return the pre-separated large particles. In this way, before the dust-laden gas enters the electrostatic separation device, large particles (mainly coarse germanium particles) are pre-separated by the cyclone separator, preventing them from clogging the subsequent charging and separation chambers. At the same time, the large germanium particles are directly reused, reducing losses.

[0041] In some implementations, please refer to Figure 3 and Figure 4As the drive mechanism drives the scraper 403 to push impurities upwards and then return downwards, residual impurities that fall from the scraper 403 or the dust collection inlet 3031 are re-adsorbed onto the surface of the deflection plate 201 under the influence of the electric field, ready for the next push. When the scraper 403 pushes impurities upwards, some impurity particles may slip off the scraper edge or the dust collection inlet 3031. These fallen impurities fall back into the vertical channel of the separation chamber 200 under gravity. Because the electric field between the deflection plate 201 and the counter plate 202 is always present, these impurities (still carrying residual charge) will be re-adsorbed by the deflection plate 201. In the next cleaning cycle, they will be pushed back and discharged by the scraper 403. Even if a small amount of impurities fail to be sucked away by the negative pressure in time and fall during the scraper pushing process, they can be automatically recaptured by the electric field, preventing them from falling back and contaminating the collected germanium powder.

[0042] In some implementations, please refer to Figure 3 The bottom of the collecting hopper 204 is equipped with an airlock discharge valve (e.g., a star-shaped discharge valve or a double gate valve) to discharge the collected germanium particles while maintaining a sealed state. In some examples, the airlock discharge valve employs a rotating impeller or an alternating opening and closing double gate structure to prevent external air from entering the separation chamber 200 while continuously discharging germanium powder, thus avoiding disruption of the vacuum environment or introduction of oxygen that could lead to oxidation of the germanium powder.

[0043] In some implementations, please refer to Figures 1 to 4 This application provides a method for electrostatic separation of germanium-containing dust applied to any of the aforementioned electrostatic separation devices for germanium-containing dust, comprising the following steps: Step 1: Introduce the airflow containing germanium dust into the charging chamber 100, and charge the dust particles by discharging through the corona electrode 101.

[0044] Step 2: The charged airflow is introduced into the separation chamber 200. In the vertical electric field between the deflection plate 201 and the counter plate 202, the difference in charge retention ability between germanium dust and insulating impurities is utilized to cause the insulating impurities to be adsorbed onto the surface of the deflection plate 201, while the germanium dust, due to charge leakage, is not affected by the electric field force and falls into the collection hopper 204 for collection under the action of gravity.

[0045] Step 3: When the impurities adsorbed on the surface of the deflection plate 201 accumulate to a set level, drive the scraper 403 to move from bottom to top along the surface of the deflection plate 201, pushing the impurities to the dust collection inlet 3031 at the top of the deflection plate 201.

[0046] This method is simple to operate, has controllable parameters, and stably and effectively improves the recovery efficiency and purity of germanium dust without secondary pollution, making it suitable for widespread application in germanium pretreatment production lines.

[0047] The above are merely some embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. An electrostatic separation device for germanium-containing dust, characterized in that, include: A charging chamber (100) is provided with a corona electrode (101) for charging dust particles in a germanium-containing dust airflow. A separation chamber (200) is connected at the top to the charging chamber (100). A deflection plate (201) and a counter plate (202) are provided in the separation chamber (200). A vertical airflow channel is formed between the deflection plate (201) and the counter plate (202). The deflection plate (201) is connected to a high-voltage power supply to adsorb the charged insulating impurities. A collection hopper (204) for collecting germanium particles is provided at the bottom of the separation chamber (200). A scraper device (400) is disposed in the lower part of the separation chamber (200), including a scraper (403) and a driving mechanism. The scraper (403) can move upward along the surface of the deflection plate (201) under the action of the driving mechanism, pushing the impurities adsorbed on the deflection plate (201) upward; and A negative pressure impurity removal zone (300) is located at the top of the separation chamber (200) and above the deflection plate (201). The negative pressure impurity removal zone (300) is separated from the separation chamber (200) by a partition (301). A gap is left between the lower end of the partition (301) and the top end of the deflection plate (201) to form a dust collection inlet (3031). The negative pressure impurity removal zone (300) is connected to a negative pressure source for sucking away impurities when the scraper (403) pushes impurities into the negative pressure impurity removal zone (300) through the dust collection inlet (3031).

2. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that, The scraper device (400) further includes: A bracket (401) and an electric push rod (402); the bracket (401) is fixed to the bottom of the outer shell of the separation chamber (200), and the electric push rod (402) is mounted on the bracket (401). The telescopic end of the electric push rod (402) extends into the separation chamber (200) and is connected to the scraper (403) to drive the scraper (403) to rise and fall.

3. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that: The separator (301) has a sheet-like extension (3011) extending toward the deflection plate (201), and the dust collection inlet (3031) is formed between the end of the extension (3011) and the top of the deflection plate (201).

4. The electrostatic separation device for germanium-containing dust according to claim 3, characterized in that: An elastic sealing body (3012) is provided on the separator (301). The elastic sealing body (3012) is located on the side of the extension (3011) facing the deflection plate (201). The extension (3011), the elastic sealing body (3012) and the top of the deflection plate (201) directly enclose the dust collection inlet (3031). When the scraper (403) pushes impurities to the dust collection inlet (3031), the scraper (403) abuts against the elastic sealing body (3012), thereby temporarily isolating the negative pressure impurity removal zone (300) from the airflow channel of the separation chamber (200).

5. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that: The negative pressure impurity removal zone (300) includes a dust collection chamber (303) formed by the enclosure of the separator (301), the upper end of the deflection plate (201) and part of the inner wall of the separation chamber (200), and a dust suction hood (302) disposed on one side of the dust collection chamber (303). The dust suction hood (302) has a dust suction chamber (3021) inside that communicates with the dust collection chamber (303), and the dust suction chamber (3021) is connected to the negative pressure source.

6. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that: The charged chamber (100) and the separation chamber (200) are arranged in a stacked structure, and the bottom end of the charged chamber (100) and the top end of the separation chamber (200) are directly connected through a connecting straight pipe (203).

7. The electrostatic separation device for germanium-containing dust according to claim 6, characterized in that: A removable perforated flow equalization plate (2031) is provided at one end of the connecting straight pipe (203) near the separation chamber (200); the internal space of the connecting straight pipe (203) above the perforated flow equalization plate (2031) forms a pre-settling zone (2032); the perforated flow equalization plate (2031) has an opening ratio of 30% to 50% and a hole diameter of 5mm to 10mm, and is used to evenly distribute the pre-settled airflow into the separation chamber (200).

8. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that: The corona electrode (101) of the charged chamber (100) is connected to a pulsed high-voltage power supply. The pulsed high-voltage power supply outputs a negative polarity pulse voltage with a pulse width of 50μs to 200μs, a pulse frequency of 50Hz to 500Hz, and a peak voltage of -20kV to -30kV.

9. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that, Also includes: A cyclone separator and a blower are provided. The inlet of the cyclone separator is connected to multiple dust collection points above the closed vibrating conveyor trough for dried germanium particles. The gas outlet of the cyclone separator is connected to the blower, and the outlet of the blower is connected to the inlet of the charging chamber (100). The bottom discharge port of the cyclone separator is connected to the closed vibrating conveyor trough for returning the pre-separated large particles.

10. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that: During the process of the drive mechanism driving the scraper (403) to push impurities upward and return to downward movement, the residual impurities that fall from the scraper (403) or the dust collection inlet (3031) are re-adsorbed onto the surface of the deflection plate (201) under the action of the electric field of the deflection plate (201) for the next push.

11. The electrostatic separation device for germanium-containing dust according to claim 1, characterized in that: The bottom of the collecting hopper (204) is equipped with an airlock discharge valve, which is used to discharge the collected germanium particles while maintaining a sealed state.

12. The electrostatic separation method for germanium-containing dust using the electrostatic separation apparatus for germanium-containing dust according to any one of claims 1 to 11, characterized in that, Includes the following steps: Step 1: Introduce the airflow containing germanium dust into the charging chamber (100), and charge the dust particles by discharging through the corona electrode (101); Step 2: The charged airflow is introduced into the separation chamber (200). In the vertical electric field between the deflection plate (201) and the counter plate (202), the difference in charge retention ability between germanium dust and insulating impurities is utilized to cause the insulating impurities to be adsorbed on the surface of the deflection plate (201), while the germanium dust is not affected by the electric field force due to charge leakage and falls into the collection hopper (204) under the action of gravity for collection. Step 3: When the impurities adsorbed on the surface of the deflection plate (201) accumulate to a set level, drive the scraper (403) to move from bottom to top along the surface of the deflection plate (201) and push the impurities to the dust collection inlet (3031) at the top of the deflection plate (201). Step 4: At the same time or after the impurities are pushed to the dust collection inlet (3031), start the negative pressure source to suck the impurities into the negative pressure impurity removal zone (300) and discharge them out of the separation chamber (200). Step 5: After the scraper (403) completes the push, it returns downward. During the return process, the residual impurities that fall from the scraper (403) or the dust collection inlet (3031) fall back into the electric field area of ​​the deflection plate (201) and are adsorbed on the surface of the deflection plate (201) again, waiting for the next push.

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