Plasma germanium evaporation furnace

Abstract

The utility model relates to metallurgical chemical industry technical field, concretely is a kind of plasma germanium volatilization furnace, including pretreatment unit, core reaction cavity, directional deposition chamber and tail gas treatment system;The pretreatment unit is communicated with the top of core reaction cavity by vacuum transition cabin, the bottom of core reaction cavity is connected with directional deposition chamber by vertical connecting passage, and the lower part of directional deposition chamber is connected with tail gas treatment system by horizontal pipeline;The core reaction cavity is multilayer composite cylindrical structure;Ring permanent-magnetic confinement array and laminar jet nozzle group are located inside the directional deposition chamber;The tail gas treatment system includes quench tower, dust removal device, catalytic reactor and adsorption purification tower in turn along airflow direction.The equipment can realize accurate temperature control using plasma technology heating, improve energy utilization rate, and the tail gas treatment system of the equipment integrates four-stage purification, reduces the pollution to environment.

Description

Technical Field

[0001] This utility model relates to the field of metallurgical and chemical technology, specifically to a plasma germanium volatilization furnace. Background Technology

[0002] Germanium is an important rare metal widely used in semiconductors, fiber optic communications, infrared optics, and other fields. The industrial production of germanium mainly involves the following steps: First, germanium is enriched from germanium-containing raw materials such as lignite and soot through a high-temperature reduction volatilization method, yielding germanium-containing soot. Next, the enriched germanium concentrate is reacted with concentrated hydrochloric acid to generate germanium tetrachloride (GeCl4), which is then purified by distillation to remove impurities. Then, germanium tetrachloride is converted to high-purity germanium dioxide (GeO2) through a hydrolysis reaction, followed by drying and calcination. Finally, germanium dioxide is reduced with hydrogen at high temperature to obtain metallic germanium, which is then processed into high-purity germanium single crystals using zone melting and single-crystal growth techniques. Enrichment of germanium is a crucial step in the production process. It is typically extracted from germanium-containing raw materials such as lignite, soot, or slag. Through a high-temperature reduction volatilization method, using a rotary kiln or vertical tank at approximately 1100℃, germanium dioxide is reduced to volatile germanium monoxide, which is then released into the flue gas and enriched in the soot. This germanium-containing soot is subsequently collected as raw material for the extraction of high-purity germanium. Currently, the high-temperature volatilization method typically uses fossil fuel combustion for heating, which has problems such as low energy utilization efficiency, high carbon emissions, and difficulty in temperature control.

[0003] In view of this, we propose a plasma germanium volatilization furnace. Utility Model Content

[0004] The purpose of this invention is to provide a plasma germanium volatilization furnace to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A plasma germanium volatilization furnace includes a pretreatment unit, a core reaction chamber, a directional deposition chamber, and a tail gas treatment system. The pretreatment unit is connected to the top of the core reaction chamber via a vacuum transition chamber, the bottom of the core reaction chamber is connected to the directional deposition chamber via a vertical connecting channel, and the lower part of the directional deposition chamber is connected to the tail gas treatment system via a horizontal pipe. The core reaction chamber is a multi-layered composite cylindrical structure, including a high-temperature resistant inner lining layer, a heat shield layer, an active cooling layer and a vacuum sealing layer arranged sequentially from the inside to the outside. A plasma generation system is installed inside the core reaction chamber. The directional deposition chamber is equipped with a ring-shaped permanent magnet confinement array and a laminar flow nozzle group. The inner wall of the directional deposition chamber is provided with a surrounding deposition substrate. The permanent magnet confinement array is arranged around the deposition substrate, and the laminar flow nozzle group is inclined towards the surface of the deposition substrate. The exhaust gas treatment system includes, in sequence along the airflow direction, a quench tower, a dust removal device, a catalytic reactor, and an adsorption purification tower.

[0006] Furthermore, the plasma generation system includes: a radio frequency coupler, multiple microwave waveguide interfaces, and a helical grid electrode. The radio frequency coupler is installed on the top of the core reaction cavity and arranged coaxially with the cavity axis; the multiple microwave waveguide interfaces are located below the radio frequency coupler and symmetrically arranged on the side wall of the core reaction cavity; the helical grid electrode is located on the central axis of the core reaction cavity and below the radio frequency coupler.

[0007] Furthermore, the vertical connection channel includes: a corrugated pipe compensation section and a tapered flow guide structure. The two ends of the corrugated pipe compensation section are respectively connected to the outlet of the core reaction chamber and the inlet of the tapered flow guide structure. The outlet of the tapered flow guide structure is connected to the directional deposition chamber. The tapered flow guide structure is provided with multiple air extraction ports.

[0008] Furthermore, the inner diameter of the inlet end of the tapered flow guide structure is larger than that of the outlet end.

[0009] Furthermore, a sealed transition structure is provided at the interface between the bellows compensation section and the tapered flow guide structure.

[0010] Furthermore, the quench tower is a vertical tower with an atomizing spray device at the top.

[0011] Furthermore, the active cooling layer has a jacketed structure, and the active cooling layer has a cooling channel that spirals around the cavity inside. The inlet and outlet of the cooling channel are connected to the cooling water system.

[0012] Compared with the prior art, the beneficial effects of this utility model are: 1. This plasma germanium volatilization furnace directly heats the plasma by exciting it with electrical energy, eliminating the need for fuel combustion, thus improving energy utilization efficiency and reducing energy consumption.

[0013] 2. This plasma germanium volatilization furnace uses plasma technology to achieve precise temperature control, ensuring that the reaction chamber is always at the optimal operating temperature.

[0014] 3. This plasma germanium volatilization furnace uses electrically excited plasma heating and operates in a full vacuum or inert gas environment, with no combustion exhaust emissions. The exhaust gas treatment system integrates four-stage purification (rapid cooling + catalytic oxidation + washing + adsorption), reducing environmental pollution. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the core reaction chamber structure in this utility model.

[0016] In the diagram: 1. Pretreatment unit; 11. Ultrasonic cleaning tank; 12. Vacuum drying chamber; 13. Preheating chamber; 2. Core reaction chamber; 21. Inner liner; 22. Thermal shielding layer; 23. Active cooling layer; 231. Cooling channel; 24. Vacuum sealing layer; 25. Plasma generation system; 251. Radio frequency coupler; 252. Microwave waveguide interface; 253. Helical grid electrode; 3. Directional deposition chamber; 31. Annular permanent magnet confinement array; 32. Laminar flow nozzle group; 33. Deposition substrate 34. Vacuum chamber; 35. Gas extraction pipe; 36. First substrate support; 37. Optical monitoring window; 4. Exhaust gas treatment system; 41. Quenching tower; 411. Atomizing spray device; 42. Dust removal device; 421. Second substrate support; 43. Catalytic reactor; 44. Adsorption purification tower; 5. Vacuum transition chamber; 6. Vertical connection channel; 61. Corrugated pipe compensation section; 62. Gradual converging flow guide structure; 63. Sealed transition structure; 64. Gas extraction interface; 7. Horizontal pipeline. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0019] In the description of this patent, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection or setting, a detachable connection or setting, or an integral connection or setting. Those skilled in the art can understand the specific meaning of the above terms in this patent according to the specific circumstances.

[0020] Furthermore, 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "several" means two or more, unless otherwise explicitly specified.

[0021] Please see Figures 1-2 As shown, this utility model provides a technical solution: A plasma germanium volatilization furnace includes a pretreatment unit 1, a core reaction chamber 2, a directional deposition chamber 3, and a tail gas treatment system 4. The pretreatment unit 1 is connected to the top of the core reaction chamber 2 through a vacuum transition chamber 5. The bottom of the core reaction chamber 2 is connected to the directional deposition chamber 3 through a vertical connecting channel 6. The lower part of the directional deposition chamber 3 is connected to the tail gas treatment system 4 through a horizontal pipe 7.

[0022] The pretreatment unit 1 includes an ultrasonic cleaning tank 11, a vacuum drying chamber 12, and a preheating chamber 13 arranged coaxially from top to bottom, and a pneumatic gate valve is provided in the vacuum transition chamber 5.

[0023] The spatial layout of each module of the equipment satisfies the following: the pretreatment unit 1, the core reaction chamber 2, and the directional deposition chamber 3 are arranged vertically from top to bottom, which can simplify material transportation and improve space utilization by utilizing gravity; the exhaust gas treatment system 4 is located below the side of the directional deposition chamber 3, which can reduce pipe bends and keep the airflow smooth.

[0024] The core reaction chamber 2 is a multi-layered composite cylindrical structure, comprising, from the inside out, a high-temperature resistant inner lining layer 21, a heat shield layer 22, an active cooling layer 23, and a vacuum sealing layer 24. This multi-layered composite structure, through functional layering, material synergy, and thermal optimization, addresses multiple challenges such as high temperature, vacuum, and corrosion, thereby improving efficiency and extending lifespan. The active cooling layer 23 is a jacketed structure, with a spiral cooling channel 231 encircling the chamber inside. The inlet and outlet of the cooling channel 231 are connected to a cooling water system. The heat shield layer 22 isolates most of the heat; the small amount of heat conducted away is exchanged through the active cooling layer 23, preventing heat transfer to the outside.

[0025] The directional deposition chamber 3 is equipped with an annular permanent magnet confinement array 31 and a laminar flow nozzle group 32. A deposition substrate 33 is arranged around the inner wall of the directional deposition chamber 3. The permanent magnet confinement array 31 is arranged around the deposition substrate 33, and the laminar flow nozzle group 32 is inclined towards the surface of the deposition substrate 33. The exhaust gas treatment system 4 includes, in sequence along the airflow direction, a quench tower 41, a dust removal device 42, a catalytic reactor 43, and an adsorption purification tower 44. Each treatment unit is connected in series via flange pipes. The quench tower 41 is a vertical tower with an atomizing spray device 411 at the top. The dust removal device 42 has a detachable second substrate support 421 at its bottom, which is fixed to the bottom of the dust removal device 42 via a quick-install flange.

[0026] In one embodiment, a plasma generation system 25 is provided inside the core reaction cavity 2. The plasma generation system 25 includes: a radio frequency coupler 251, multiple microwave waveguide interfaces 252, and a spiral grid electrode 253. The radio frequency coupler 251 is installed on the top of the core reaction cavity 2 and arranged coaxially with the cavity axis. The multiple microwave waveguide interfaces 252 are located below the radio frequency coupler 251 and are symmetrically arranged on the side wall of the core reaction cavity 2. The spiral grid electrode 253 is located on the central axis of the core reaction cavity 2 and below the radio frequency coupler 251.

[0027] In one embodiment, the vertical connection channel includes a bellows compensation section 61 and a tapered flow guide structure 62. The bellows compensation section 61 is connected at both ends to the outlet of the core reaction chamber 2 and the inlet of the tapered flow guide structure 62, respectively. The outlet of the tapered flow guide structure 62 is connected to the directional deposition chamber 3. The inner diameter of the inlet of the tapered flow guide structure 62 is larger than that of the outlet. A sealing transition structure 63 is provided at the interface between the bellows compensation section 61 and the tapered flow guide structure 62. The sealing transition structure 63 reduces mechanical wear and extends service life. The tapered flow guide structure 62 is provided with multiple suction ports 64. Multi-stage suction can reduce pressure in stages, reduce the load on a single pump, improve suction efficiency, and also help cope with emergencies, improving system reliability.

[0028] In one embodiment, the directional deposition chamber 3 includes: a cylindrical vacuum chamber 34 and a detachable first substrate support 36. The bottom of the cylindrical vacuum chamber 34 is symmetrically provided with air extraction pipes 35. The detachable first substrate support 36 is fixed to the bottom of the cylindrical vacuum chamber 34 by a quick-install flange. An optical monitoring window 37 is provided on the side wall of the directional deposition chamber 3 to monitor the status of the directional deposition chamber 3.

[0029] Taking the preparation of high-purity germanium sheets as an example, the specific operation steps are as follows: Raw material pretreatment: During raw material pretreatment, the germanium raw material is first placed in the ultrasonic cleaning tank 11, and dual-frequency ultrasonic cleaning is started. After cleaning, the material is conveyed to the vacuum drying chamber 12 and dried inside the vacuum drying chamber 12. The dried germanium block is then transferred to the preheating chamber 13 for preheating.

[0030] Plasma volatilization reaction: The preheated germanium raw material falls into the core reaction chamber 2, and the radio frequency coupler 251 excites the plasma. A bias voltage is applied to the spiral grid electrode 253, and helium gas is used for countercurrent cooling to maintain the electrode temperature.

[0031] Directional deposition: Gaseous germanium enters the directional deposition chamber 3 through the connecting channel, and the magnetic field generated by the annular permanent magnet array 31 constrains the movement direction of germanium ions. The laminar flow nozzle assembly 32 focuses the gas flow onto the surface of the deposition substrate 33 to form a uniform germanium film.

[0032] Exhaust gas treatment: The temperature of the exhaust gas drops sharply in the quench tower 41, causing germanium oxide to condense into particulates. These particulates are captured by a bag filter, and volatile organic compounds are decomposed in the catalytic reactor 43. Acidic gases are neutralized in the adsorption purification tower 44, and residual pollutants are adsorbed by activated carbon before being discharged in compliance with standards.

[0033] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A plasma germanium volatilization furnace, comprising a pretreatment unit, a core reaction chamber, a directional deposition chamber, and a tail gas treatment system; characterized in that, The pretreatment unit is connected to the top of the core reaction chamber through a vacuum transition chamber, and the bottom of the core reaction chamber is connected to the directional deposition chamber through a vertical connecting channel. The lower part of the directional deposition chamber is connected to the exhaust gas treatment system through a horizontal pipe. The core reaction chamber is a multi-layered composite cylindrical structure, including a high-temperature resistant inner lining layer, a heat shield layer, an active cooling layer and a vacuum sealing layer arranged sequentially from the inside to the outside. A plasma generation system is installed inside the core reaction chamber. The directional deposition chamber is equipped with a ring-shaped permanent magnet confinement array and a laminar flow nozzle group. The inner wall of the directional deposition chamber is provided with a surrounding deposition substrate. The permanent magnet confinement array is arranged around the deposition substrate, and the laminar flow nozzle group is inclined towards the surface of the deposition substrate. The exhaust gas treatment system includes, in sequence along the airflow direction, a quench tower, a dust removal device, a catalytic reactor, and an adsorption purification tower.

2. The plasma germanium volatilization furnace according to claim 1, characterized in that, The plasma generation system includes: a radio frequency coupler, multiple microwave waveguide interfaces, and a spiral grid electrode. The radio frequency coupler is installed on the top of the core reaction cavity and arranged coaxially with the cavity axis. The multiple microwave waveguide interfaces are located below the radio frequency coupler and are symmetrically arranged on the side wall of the core reaction cavity. The spiral grid electrode is located on the central axis of the core reaction cavity and below the radio frequency coupler.

3. The plasma germanium volatilization furnace according to claim 1, characterized in that, The vertical connection channel includes: a corrugated pipe compensation section and a tapered flow guide structure. The two ends of the corrugated pipe compensation section are respectively connected to the outlet of the core reaction chamber and the inlet of the tapered flow guide structure. The outlet of the tapered flow guide structure is connected to the directional deposition chamber. The tapered flow guide structure is provided with multiple air extraction ports.

4. A plasma germanium volatilization furnace according to claim 3, characterized in that, The inner diameter of the inlet end of the tapered flow guide structure is larger than that of the outlet end.

5. A plasma germanium volatilization furnace according to claim 3, characterized in that, A sealed transition structure is provided at the interface between the bellows compensation section and the tapered flow guide structure.

6. The plasma germanium volatilization furnace according to claim 1, characterized in that, The quench tower is a vertical tower with an atomizing spray device at the top.

7. The plasma germanium volatilization furnace according to claim 1, characterized in that, The active cooling layer has a jacketed structure, and the active cooling layer has a cooling channel that spirals around the cavity. The inlet and outlet of the cooling channel are connected to the cooling water system.

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