A method for rapidly converting tungsten filament waste into oxides

Abstract

This invention discloses a method for rapidly converting tungsten wire waste into oxides. The specific process includes: pulverizing the tungsten wire waste and dielectric barrier discharge plasma-assisted high-temperature ball milling oxidation. The high-temperature ball milling oxidation is carried out in a high-temperature rotary furnace. The high-temperature rotary furnace contains metal grinding balls and dielectric-covered metal electrodes. The tungsten wire is ionized and oxidized in an oxygen atmosphere within the range of 650-750°C. Low-speed mechanical grinding ensures that the grinding balls achieve mechanical stripping of oxide powder with minimal damage to the high-temperature brittle inner wall of the rotary furnace. Localized plasma bombardment accelerates the high-temperature oxidation of the tungsten wire and can further bombard and separate the surface oxides, thereby exposing the inner unoxidized layer and accelerating the oxidation rate. This method achieves the ability to convert tungsten wire waste into oxides in one step, rapidly obtaining the preparation of oxides.

Description

Technical Field

[0001] This application relates to the technical field of tungsten filament waste treatment, and more specifically, to a method for rapidly converting tungsten filament waste into oxides. Background Technology

[0002] Common tungsten wire waste mainly includes tungsten wire after nickel removal, waste tungsten wire generated during production, and tungsten-nickel diamond wire generated in the photovoltaic industry. Because the treatment and recycling of tungsten wire waste is of great significance and value, most tungsten wire waste generated in production and processing stages is treated and recycled. One of the more common treatment methods is the preparation of tungsten oxide.

[0003] Currently, the main method for processing tungsten wire waste into tungsten oxide is the sulfation-roasting-water leaching-calcination method. Although this method can effectively produce tungsten oxide, it is relatively complex, difficult, and time-consuming, involving sulfation treatment, roasting, water leaching, and calcination, which affects the efficiency of tungsten oxide production. Summary of the Invention

[0004] The purpose of this application is to provide a method for rapidly converting tungsten wire waste into oxides. This method is relatively simple to operate, has low difficulty, and is quick to prepare oxides, thereby greatly improving the preparation efficiency of oxides.

[0005] To achieve the above objectives, this application provides a method for rapidly converting tungsten filament waste into oxides, comprising:

[0006] The specific details of the invention are as follows:

[0007] Oxide powder is prepared from tungsten wire waste through oxidation and pulverization using a high-temperature rotary furnace with a set holding and calcination period, under an oxygen atmosphere, high-temperature oxidation, plasma discharge bombardment, and mechanical grinding with graded grinding balls.

[0008] Preferably, the tungsten wire waste is shredded by a shredder to prepare standard tungsten wires, and the length of some of the standard tungsten wires is between 1 and 2 times the maximum diameter of the graded grinding balls.

[0009] More preferably, the length of the standard tungsten wire is between 1 and 1.5 times the maximum diameter of the graded grinding balls.

[0010] More preferably, the standard tungsten wire with a content of 20-30% has a length greater than the maximum diameter of the graded grinding balls.

[0011] The length of the standard tungsten wire is limited to ensure sufficient buffering force during heating and speed-up, preventing damage caused by collisions between the graded grinding balls and the inner wall of the high-temperature rotary furnace.

[0012] Preferably, the gradation grade of the gradation grinding balls is 2 to 5.

[0013] More preferably, the gradation of the grading grinding balls is three-stage, with the first stage having a diameter of 18-22 mm, the second stage having a diameter of 13-17 mm, and the third stage having a diameter of 8-12 mm.

[0014] More preferably, the material of the graded grinding balls is one or more of stainless steel, hard steel or tungsten carbide.

[0015] More preferably, the weight ratio of the graded grinding balls to the standard tungsten wire is 1 to 3:1, and the total volume of the grinding balls accounts for 1 / 3 to 2 / 5 of the volume of the high-temperature rotary furnace cavity.

[0016] Too little filler will affect the throughput, while too much filler will hinder the efficiency of discharge plasma treatment and grinding.

[0017] Preferably, the high-temperature oxidation involves quantitatively placing the standard tungsten wire and graded grinding balls into the high-temperature rotary furnace cavity, and oxidizing at a high temperature of 650–750°C under an oxygen atmosphere. The operating speed of the high-temperature rotary furnace is the same as the speed at which the grinding balls are in a slipping state. The excitation voltage of the plasma is 15–30 kV, the operating current is 3–5 A, and the discharge frequency is 10–30 kHz.

[0018] Dielectric barrier discharge plasma contains a large number of highly reactive particles, such as electrons, ions, and metastable particles, within its discharge region. Using an oxygen atmosphere during plasma discharge generates reactive oxygen ions, which more readily combine with the active sites of the tungsten filament, thus achieving rapid oxide formation.

[0019] Preferably, the discharge plasma operates in a pulsed discharge mode, with a pulse voltage frequency of 20–30 kHz.

[0020] The macroscopic discharge pulses formed by active particles can instantaneously heat the surface of the tungsten filament, while the powder temperature drops sharply during the pulse interval or upon leaving the plasma. This repeated heating and cooling process induces enormous thermal stress, thereby promoting powder fragmentation and refinement. In an oxygen atmosphere, localized heating increases the oxidation rate of the tungsten filament surface, altering the surface grain structure. This allows for the preparation and stripping of oxides in a high-temperature rotary furnace without the need for traditional high-temperature conditions.

[0021] Preferably, the high-temperature oxidation consists of a heating and calcination period of 2 to 3 hours and a holding and calcination period of 2 to 4 hours.

[0022] More preferably, the heating and calcination period consists of a slow heating period of 2 to 3 hours at the first operating speed and a rapid heating period of 30 minutes, and the heat preservation and calcination period consists of a constant temperature period at the second operating speed.

[0023] More preferably, the first operating speed during the heating and calcination period is lower than the second operating speed during the heat preservation and calcination period.

[0024] Preferably, the operating speed is 40-50% of the critical speed of the high-temperature rotary furnace.

[0025] More preferably, the diameter D of the cavity rotation direction of the high-temperature rotary furnace is in the range of 0.5 to 1.5 m, and the critical speed is...

[0026] More preferably, the diameter of the high-temperature rotary furnace is 1m, and the operating speed is 15-22r / min.

[0027] The critical point at which the grinding balls transition from sliding to pelting is approximately 50% of the critical rotational speed. Below this speed, they merely slide; above it, they begin to pelt; and above the critical speed, they centrifugally rotate against the wall. Since the inner wall of a high-temperature rotary furnace is generally made of a high-temperature brittle material, pelting can easily damage it. Therefore, the rotational speed during the sliding state is used as the operating speed. To compensate for the lower grinding energy caused by the sliding state, which prevents the tungsten oxide wire from being sufficiently ground, this invention uses discharge plasma as a replacement method.

[0028] Preferably, the plasma discharge bombardment period is the heat preservation and calcination period, the working atmosphere is an oxygen atmosphere, and the working oxygen content is 60-70%.

[0029] Preferably, after the high-temperature oxidation is completed, the rotation speed of the high-temperature rotary furnace is adjusted to the third cooling working speed, and the furnace is allowed to cool naturally to room temperature.

[0030] More preferably, the third operating speed for cooling is lower than the second operating speed.

[0031] Preferably, the oxide powder has an oxidation rate of more than 99% and the particle size of the oxide is less than 100 mesh.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] (1) This invention is particularly suitable for converting tungsten wire waste such as nickel-removed tungsten wire, waste tungsten wire generated during the production process, and tungsten-nickel diamond wire generated in the photovoltaic industry into oxides. This method uses a shredder to obtain tungsten wire waste of suitable size, which is suitable for buffering the grinding balls during high-temperature rotary furnace ball milling but ensuring that they are not too long and thus do not cause entanglement and difficulty in grinding.

[0034] (2) The high-temperature resistant grinding ball operates in a sliding state under the premise of ensuring low wear under high temperature conditions on the surface of the metal ball. The metal grinding ball ensures high ball mill energy transfer efficiency, thereby ensuring the mechanical processing efficiency of tungsten wire waste in the low-speed rotating high-temperature rotary furnace.

[0035] (3) The introduction of dielectric barrier discharge plasma, under the premise of ensuring that the metal wire in the high-temperature converter cavity does not become electrode contaminated, provides active particles including electron flow and ion flow, which impact the metal surface with high height and high energy. The energy carried will be transferred to the material in the form of heat, causing the local rapid heating of the tungsten wire to reduce the calcination temperature requirement of the high-temperature rotary furnace, accelerating the oxidation of the tungsten wire surface, lattice growth and even mismatch melting. During the rotation, the temperature difference changes cause the surface oxide layer to generate thermal stress release demand, and finally achieves the state of rapid oxidation of the tungsten wire surface and loose and easy peeling of the oxide layer, which is beneficial to ball milling powder production.

[0036] (4) The dielectric barrier discharge plasma ball milling oxidation method improves the oxidation rate and conversion rate of tungsten wire. This method is relatively simple to operate and takes less time, thus achieving the purpose of rapid preparation of powder oxide. Attached Figure Description

[0037] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the method flow of the present invention.

[0039] Figure 2 This is a schematic diagram of the dielectric barrier discharge plasma ball milling high-temperature oxidation of the present invention.

[0040] The reference numerals in the attached diagram are as follows: 1-base, 2-graded grinding balls, 3-high-temperature rotary furnace, 4-medium barrier layer, 5-metal electrode, 6-temperature control power supply, 7-high frequency power supply, 8-oxygen source, 9-tungsten wire waste, 10-oxide powder, 11-inner wall of rotary furnace. Detailed Implementation

[0041] The endpoints and any values ​​of the ranges disclosed in this invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this invention.

[0042] See Figure 1 , Figure 1 This is a flowchart illustrating a method for rapidly converting tungsten filament waste into oxides, as provided in an embodiment of this application.

[0043] This application provides a method for rapidly converting tungsten filament waste into oxides, comprising the following steps:

[0044] S1: Material preparation, including crushing tungsten wire waste and quantitative preparation of graded grinding balls, which are then placed into the high-temperature rotary furnace cavity;

[0045] S2: Heating and preheating calcination, including slow heating and rapid heating in a high-temperature rotary furnace, and ensuring that the gradation grinding balls are in a slippery state at the first working speed;

[0046] S3: Insulation and calcination. Under the set temperature conditions, the high-temperature rotary furnace operates at the second working speed and performs plasma discharge bombardment in an appropriate oxygen atmosphere.

[0047] S4: Cooling and sieving. After natural cooling at the third working speed, oxide powder and residual filaments are sieved.

[0048] like Figure 2 As shown, the dielectric barrier discharge plasma-assisted ball milling oxidation system includes a base 1, graded grinding balls 2, a high-temperature rotary furnace 3, a dielectric barrier layer 4, a metal electrode 5, a temperature control power supply 6, a high-frequency power supply 7, an oxygen source 8, tungsten wire waste 9, oxides 10, and the inner wall of the rotary furnace 11.

[0049] The high-temperature rotary furnace 3 and the metal electrode 5 are respectively connected to the two stages of the high-frequency power supply 7 to form a discharge system. The dielectric barrier layer 4 covers the metal electrode 5 inside the cavity of the high-temperature rotary furnace 3 to form a dielectric barrier discharge plasma system.

[0050] The high-temperature rotary furnace is cylindrical with a diameter of 1m in the direction of rotation, and the inner wall of the rotary furnace is made of silicon carbide.

[0051] The specific implementation method is as follows:

[0052] Example 1:

[0053] (1) Material preparation. Waste tungsten filaments from photovoltaic applications, containing 98.5% W, are shredded using a shredder. 30% of the shredded waste tungsten filaments (9) are controlled to have a length between 20 and 24 mm. These shredded waste tungsten filaments (9) are then placed into the high-temperature rotary furnace (3) along with the graded grinding balls (2). The graded grinding balls are made of tungsten carbide with a hardness of 1100 HV. The graded grinding balls (2) are divided into three grades: the first grade has a diameter of 18 mm and accounts for 10% of the total; the second grade has a diameter of 14 mm and accounts for 50% of the total; and the third grade has a diameter of 10 mm and accounts for 40% of the total. The ratio of waste tungsten filaments (9) to the graded grinding balls (2) is 1:3, and the waste tungsten filaments (9) occupy 2 / 5 of the volume within the high-temperature rotary furnace (3).

[0054] (2) Heating and calcination. After the material is placed into the high-temperature rotary furnace 3, the operating speed of the high-temperature rotary furnace 3 is set to 18 r / min. After a slow start, the speed is increased to the operating speed, and the graded grinding balls slide off the inner wall of the rotary furnace. At the same time, the temperature control power supply 6 is turned on, and the temperature is slowly increased to 700℃ within 2.5 hours and then rapidly increased to 750℃ within 30 minutes. The heating process is the heating and forging period. Plasma discharge bombardment is not performed during the heating and calcination period.

[0055] (3) Heat preservation and calcination. After the heating and calcination period ends, the working speed is increased to 22 r / min, and the oxygen source 8 is turned on to continuously supply oxygen. It is required that the oxygen content in the cavity of the high-temperature rotary furnace 3 reaches 70%. Then, the dielectric barrier discharge plasma system is started. The high-frequency power supply 7 has a working frequency of 30 kHz, a working voltage of 25 kV, and a working current of 5 A. Discharge plasma is generated between the metal electrode 5, the inner wall 11 of the rotary furnace, and the tungsten carbide grinding ball 2. Heat preservation and calcination are continued for 4 hours.

[0056] (4) Cooling. Stop the high-frequency power supply 7 and oxygen source 8, set the cooling speed to 10r / min, reduce the speed uniformly to the third working speed, and then remove the material after it cools down to room temperature.

[0057] (5) Material screening. The graded grinding balls are screened out by a large screen, and then the oxide powder 10 is separated from the incompletely pulverized tungsten wire waste 9 by a 100-mesh screen, so as to achieve high-purity preparation of oxide powder.

[0058] Chemical analysis revealed that the oxidation rate of the powder was 98.5%, containing 98% tungsten oxide, with the remainder being tungsten carbide, silicon carbide, etc.

[0059] Example 2:

[0060] This embodiment describes the oxidation treatment of photovoltaic tungsten wire waste with a tungsten content of 99%. The dielectric barrier discharge plasma-assisted ball mill oxidation system is the same as in Example 1.

[0061] The specific implementation method is as follows:

[0062] (1) Material preparation. Waste tungsten filaments from photovoltaic applications are shredded using a shredder. 30% of the shredded waste tungsten filaments 9 have a length controlled between 20 and 24 mm. This shredded waste tungsten filaments 9, along with the graded grinding balls 2, are placed into the high-temperature rotary furnace 3. The graded grinding balls are made of stainless steel with a hardness of 550 HV. The graded grinding balls 2 are divided into three grades: the first grade has a diameter of 20 mm and accounts for 15% of the total; the second grade has a diameter of 16 mm and accounts for 45% of the total; and the third grade has a diameter of 12 mm and accounts for 40% of the total. The ratio of the waste tungsten filaments 9 to the graded grinding balls 2 is 1:3, and the waste tungsten filaments 9 occupy 2 / 5 of the volume within the high-temperature rotary furnace 3.

[0063] (2) Heating and calcination. After the material is placed into the high-temperature rotary furnace 3, the first operating speed of the high-temperature rotary furnace 3 is set to 18 r / min. After a slow start, the speed is increased to the first operating speed, and the graded grinding balls slide off the inner wall of the rotary furnace. At the same time, the temperature control power supply 6 is turned on, and the temperature is slowly increased to 700℃ within 2.5 hours and then rapidly increased to 750℃ within 30 minutes. The heating process is the heating and forging period. Plasma discharge bombardment is not performed during the heating and calcination period.

[0064] (3) Heat preservation and calcination. After the heat preservation and calcination period ends, the working speed is increased to 22 r / min, and the oxygen source 8 is turned on to continuously supply oxygen. It is required that the oxygen content in the cavity of the high-temperature rotary furnace 3 reaches 70%. Then, the dielectric barrier discharge plasma system is started. The high-frequency power supply 7 has a working frequency of 30 kHz, a working voltage of 30 kV, and a working current of 5 A. Discharge plasma is generated between the metal electrode 5, the inner wall 11 of the rotary furnace, and the tungsten carbide grinding ball 2. Heat preservation and calcination are continued for 4 hours.

[0065] (4) Cooling. Stop the high-frequency power supply 7 and oxygen source 8, set the cooling speed to 15r / min, reduce the speed uniformly to the set speed, and then remove the material after it cools down to room temperature.

[0066] (5) Material screening. The graded grinding balls are screened out by a large screen, and then the oxide powder 10 is separated from the incompletely pulverized tungsten wire waste 9 by a 100-mesh screen, so as to achieve high-purity preparation of oxide powder.

[0067] Chemical analysis revealed that the oxidation rate of the powder was 98.8%, containing 98.5% tungsten oxide, with the remainder being iron oxide, silicon carbide, etc.

[0068] Example 3:

[0069] This embodiment describes the oxidation treatment of photovoltaic tungsten filament waste containing 86.39% W and 13.72% Ni. The dielectric barrier discharge plasma-assisted ball mill oxidation system is the same as in Example 1.

[0070] The specific implementation method is as follows:

[0071] (1) Material preparation. Waste tungsten filaments from photovoltaic applications are shredded using a shredder. 30% of the shredded waste tungsten filaments 9 have a length controlled between 18 and 22 mm. This shredded waste tungsten filaments 9, along with the graded grinding balls 2, are placed into the high-temperature rotary furnace 3. The graded grinding balls are made of hard steel with a hardness of 750 HV. The graded grinding balls 2 are divided into three grades: the first grade has a diameter of 18 mm and accounts for 20% of the total; the second grade has a diameter of 14 mm and accounts for 50% of the total; and the third grade has a diameter of 10 mm and accounts for 30% of the total. The ratio of the waste tungsten filaments 9 to the graded grinding balls 2 is 1:2, and the waste tungsten filaments 9 occupy 2 / 5 of the volume within the high-temperature rotary furnace 3.

[0072] (2) Heating and calcination. After the material is placed into the high-temperature rotary furnace 3, the first operating speed of the high-temperature rotary furnace 3 is set to 15 r / min. After a slow start, the speed is increased to the first operating speed, and the graded grinding balls slide off the inner wall of the rotary furnace. At the same time, the temperature control power supply 6 is turned on, and the temperature is slowly increased to 600℃ within 2 hours and then rapidly increased to 650℃ within 30 minutes. The heating process is the heating and forging period. Plasma discharge bombardment is not performed during the heating and calcination period.

[0073] (3) Heat preservation and calcination. After the heat preservation and calcination period ends, the working speed is increased to 20 r / min, and the oxygen source 8 is turned on to continuously supply oxygen. It is required that the oxygen content in the cavity of the high-temperature rotary furnace 3 reaches 60%. Then, the dielectric barrier discharge plasma system is started. The high-frequency power supply 7 has a working frequency of 20 kHz, a working voltage of 20 kV, and a working current of 3 A. Discharge plasma is generated between the metal electrode 5, the inner wall 11 of the rotary furnace, and the tungsten carbide grinding ball 2. Heat preservation and calcination are continued for 3 hours.

[0074] (4) Cooling. Stop the high-frequency power supply 7 and oxygen source 8, set the cooling speed to 10r / min, reduce the speed uniformly to the set speed, and then remove the material after it cools down to room temperature.

[0075] (5) Material screening. The graded grinding balls are screened out by a large screen, and then the oxide powder 10 is separated from the incompletely pulverized tungsten wire waste 9 by a 100-mesh screen, so as to achieve high-purity preparation of oxide powder.

[0076] Chemical analysis revealed that the oxidation rate of the powder was 98.5%, containing 94.5% tungsten oxide, 4.6% nickel oxide, and the remainder being iron oxide, silicon carbide, etc.

[0077] Comparative Example 1

[0078] Other conditions were the same as in Example 1, but without plasma discharge bombardment, and the calcination temperature was 800°C. After 4 hours of oxidation and calcination, the tungsten oxide content was found to be 86% by sieving, and the tungsten wire waste was filamentous with incomplete oxidation inside the tungsten wire.

[0079] Comparative Example 2

[0080] Other conditions were the same as in Example 1, but plasma discharge bombardment and ball milling were not performed, and the calcination temperature was 800°C. After 4 hours of oxidation and calcination, the tungsten oxide content only reached 90% after sieving, and the tungsten wire waste was filamentous with incomplete oxidation inside the tungsten wire.

[0081] Comparative Example 3

[0082] Other conditions were the same as in Example 1, but plasma discharge bombardment and ball milling were not performed, and the calcination temperature was 650°C. After 4 hours of oxidation and calcination, the tungsten oxide content only reached 34% after sieving, and the tungsten wire waste was filamentous with incomplete oxidation inside the tungsten wire.

[0083] Comparative Example 4

[0084] Other conditions were the same as in Example 1, but plasma discharge bombardment was not performed, and the calcination temperature was 650°C. After 4 hours of oxidation and calcination, the tungsten oxide content only reached 37% after sieving, and the tungsten wire waste was filamentous with incomplete oxidation inside the tungsten wire.

[0085] The oxidation rate, tungsten oxide content, and silicon carbide content of Examples 1-3 and Comparative Examples 1-4 were determined by chemical methods, and the D50 particle size of the powder was determined by laser particle size analysis. The specific effects of the present invention were evaluated, as shown in Table 1.

[0086] Table 1

[0087] Oxidation rate 98.5％ 98.8％ 98.5％ 88.5％ 91％ 35.5％ 38.3％ Tungsten oxide 98％ 98.5％ 94.5％ 86％ 90％ 34％ 37％ silicon carbide 0.5％ 0.5％ 0.3％ 0.5％ 0.5％ 0.5％ 0.5％ Powder D50 particle size 53μm 61μm 44μm 72μm 41μm 38μm 55μm filamentous residue 0.1％ 0.1％ 0.1％ 23％ 95％ 97％ 84％

[0088] As shown in Table 1, Comparative Examples 1 and 2, although calcined at a high temperature of 800°C, could not achieve complete oxidation due to insufficient calcination time. Comparative Examples 3 and 4, at a lower temperature of 650°C, achieved a lower degree of oxidation for the same duration. Examples 1-3, however, achieved a higher level of oxidation within the same calcination time due to the localized high-temperature heating of the plasma.

[0089] The significant difference in the amount of filamentous residue after oxidation indicates that the removal rates of both filamentous residue and surface oxides are significantly lower without the addition of graded grinding balls. Although the powder D50 particle size of Comparative Examples 2 and 3 is lower, it is presumably because the degree of oxidation is lower, and the graded grinding balls can only remove the fine powder on the surface.

[0090] Furthermore, the high-temperature rotary furnace in Example 3 operates at a relatively low speed, resulting in less damage to the inner wall of the silicon carbide and thus a lower silicon carbide content in the oxide powder. Therefore, it is necessary to ensure that the slippage state of the graded grinding balls is within a reasonable range.

[0091] By comparing the product index parameters of the examples and comparative examples, it can be clearly seen that the dielectric barrier discharge plasma-assisted ball milling high-temperature oxidation method of the present invention has significant progress.

[0092] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for rapidly converting tungsten wire waste into oxides, characterized in that, The oxide powder is prepared from tungsten wire waste through oxidation and pulverization using a high-temperature rotary furnace with a set holding and calcination period, under an oxygen atmosphere, high-temperature oxidation, plasma discharge bombardment, and mechanical grinding with graded grinding balls. The process includes the following steps: S1) Tungsten material crushing: The tungsten wire waste is crushed by a shredder to prepare standard tungsten wires. The length of some standard tungsten wires is between 1 and 2 times the maximum diameter of the graded grinding balls. The gradation grade of the graded grinding balls is 2 to 5. The gradation grade of the graded grinding balls is three-level: the first level has a diameter of 18 to 22 mm, the second level has a diameter of 13 to 17 mm, and the third level has a diameter of 8 to 12 mm. S2) Tungsten oxidation: The standard tungsten wire and graded grinding balls are quantitatively placed into the high-temperature rotary furnace cavity and oxidized at a high temperature of 650-750°C in an oxygen atmosphere. The operating speed of the high-temperature rotary furnace is the speed when the grinding balls are in the slipping state. The excitation voltage of the plasma is 15-30kV, the operating current is 3-5A, and the discharge frequency is 10-30kHz. The high-temperature oxidation consists of a 2-3 hour heating and calcination period and a 2-4 hour heat preservation and calcination period; the heating and calcination period consists of a 2-3 hour slow heating section at a first operating speed and a 30-minute rapid heating section; the heat preservation and calcination period consists of a constant temperature section at a second operating speed; the first operating speed of the heating and calcination period is lower than the second operating speed of the heat preservation and calcination period.

2. The method for rapidly converting tungsten wire waste into oxides according to claim 1, characterized in that, The graded grinding balls are made of one or more of stainless steel, hard steel, or tungsten carbide. The weight ratio of the graded grinding balls to the standard tungsten wire is 1 to 3:

1. The total volume of the grinding balls accounts for 1 / 3 to 2 / 5 of the volume of the high-temperature rotary furnace cavity.

3. The method for rapidly converting tungsten wire waste into oxides according to claim 1, characterized in that, The operating speed is 40 to 50% of the critical speed of the high-temperature rotary furnace.

4. The method for rapidly converting tungsten filament waste into oxides according to claim 1, characterized in that, The plasma discharge bombardment is conducted during the heat preservation and calcination period, and the working atmosphere is an oxygen atmosphere with an oxygen content of 60-70%.

5. The method for rapidly converting tungsten filament waste into oxides according to claim 1, characterized in that, After the high-temperature oxidation is completed, the rotation speed of the high-temperature rotary furnace is adjusted to the third working speed, and it is allowed to cool down naturally to room temperature.

6. The method for rapidly converting tungsten filament waste into oxides according to claim 1, characterized in that, The oxidation rate of the oxide powder exceeds 98%.

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