Fluorine-containing gas degradation device and method based on warm plasma nozzle arc

Abstract

The present invention discloses a fluorine-containing gas degradation device and method based on a warm plasma nozzle arc. In the fluorine-containing gas degradation device based on a warm plasma nozzle arc, a high-voltage DC power supply is used to break down a carrier gas to generate a warm plasma, which ionizes and decomposes the fluorine-containing gas and reacts with an active gas to inhibit the composite reaction of the fluorine-containing gas. The device includes a gas control input system to control the input flow of the carrier gas, fluorine-containing gas, and active gas; a warm plasma generator to generate a DC arc, and the resulting warm plasma jet is rapidly cooled after passing the Laval nozzle; and an exhaust gas treatment system in which the generated acidic gas products are absorbed by an adsorbent. A buffer tank is connected to the exhaust gas outlet and a circulation pump to circulate and degrade the fluorine-containing gas multiple times, and the exhaust gas is discharged after passing the exhaust gas inspection.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas degradation, in particular to a device and method for degrading fluorine-containing gas based on a warm plasma nozzle arc. Background Art

[0002] Fluorine-containing gases such as sulfur hexafluoride are widely used in power switchgear due to their highly stable physical and chemical properties and excellent electrical insulation properties. However, due to their inherently potent greenhouse effect, direct emissions can have a significant environmental impact. As suitable alternatives have yet to be found, fluorine-containing gases remain widely used in the switchgear industry. Furthermore, due to their inherently stable physical and chemical properties, they are difficult to completely degrade. Currently, most devices simply recycle and purify fluorine-containing gases for reuse, but this recycled and purified gas struggles to meet the latest gas usage standards. Therefore, the search for an efficient method for degrading fluorine-containing gases is of great significance.

[0003] In recent years, plasma waste gas treatment technology has received widespread attention and research. Compared with traditional methods such as pyrolysis, photolysis, and catalytic degradation, plasma waste gas treatment technology has the advantages of high degradation rate, high energy efficiency, and simple principle.

[0004] Research has already been conducted on the application of cold plasma to degrade fluorinated gases. For example, Kabouzi et al. studied the changes in SF6 degradation rates under different microwave powers and concentration ranges. Son et al. used electron beam discharge plasma to study the effects of electron beam irradiation intensity, different concentration ranges, and different exposure times on SF6 degradation.

[0005] However, at present, these devices and methods have many problems, such as the generally low degradation degree of cold plasma, the long electron beam discharge time, low efficiency, etc., and some current fluorine-containing gas recovery and treatment devices only recycle but do not degrade. In fact, when treating fluorine-containing waste gas generated in the power industry, it is not only necessary to recycle, but also to degrade the recovered gas.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the Invention

[0007] In response to the problems existing in the prior art, the present invention proposes a fluorine-containing gas degradation device and method based on a warm plasma nozzle arc. Warm plasma is provided by the warm plasma nozzle arc discharge, and the characteristics of the warm plasma are utilized to decompose the fluorine-containing gas. At the same time, active gas is introduced to suppress the self-recovery characteristics of the fluorine-containing gas, and the reaction products are adsorbed by an acidic adsorbent, which has great practical value.

[0008] The purpose of the present invention is achieved through the following technical solutions: a fluorine-containing gas degradation device based on a warm plasma nozzle arc comprises:

[0009] A gas control input system comprising,

[0010] The fluorine-containing gas input circuit includes a fluorine-containing gas source, a gas valve and a mass flow meter connected in sequence to provide a fluorine-containing gas flow rate.

[0011] The active gas input circuit includes an active gas source, a gas valve and a mass flow meter connected in sequence to provide the active gas flow.

[0012] an inert gas input circuit, comprising an inert gas source, a gas valve, and a mass flow meter connected in sequence to provide an inert gas flow rate;

[0013] A warm plasma generator comprising,

[0014] Insulation base,

[0015] The anode is inserted into the insulating base and is provided with a reaction gas inlet. The fluorine-containing gas from the fluorine-containing gas input line and the active gas from the active gas input line are mixed and then introduced into the reaction gas inlet.

[0016] a cathode fixedly connected to the insulating base and surrounding the anode, wherein the cathode is provided with an inert gas inlet, and an inert gas from an inert gas input line is introduced into the inert gas inlet;

[0017] A ceramic tube is provided through the cathode and faces the anode. The ceramic tube, cathode and anode form a reaction space for generating warm plasma. The ceramic tube is provided with a Laval nozzle.

[0018] The harmless treatment system includes:

[0019] an acidic gas adsorbent disposed in the tail portion of the ceramic tube to absorb the acidic gas generated by the reaction;

[0020] A buffer tank is connected to the ceramic tube and is provided with an exhaust gas outlet for discharging degradation exhaust gas.

[0021] A circulation pump has one end connected to the buffer tank and the other end connected to the reaction gas inlet so as to refill the anode with gas for reaction.

[0022] In the fluorine-containing gas degradation device based on warm plasma nozzle arc, the end of the anode has at least one first inclined surface, and the cathode has a second inclined surface parallel to and opposite to the first inclined surface.

[0023] In the fluorine-containing gas degradation device based on warm plasma nozzle arc, the anode is a hollow structure.

[0024] In the fluorine-containing gas degradation device based on the warm plasma nozzle arc, the cathode has an annular channel inclined downward, and the annular channel is connected to the inert gas inlet to form a spiral input gas path.

[0025] In the fluorine-containing gas degradation device based on the warm plasma nozzle arc, the warm plasma generator also includes a sealing flange connecting the cathode and the ceramic tube.

[0026] In the fluorine-containing gas degradation device based on warm plasma nozzle arc, the insulating base is a polytetrafluoroethylene base.

[0027] In the fluorine-containing gas degradation device based on the warm plasma nozzle arc, the positive and negative electrodes of the DC power supply are respectively connected to the anode and the cathode to form a circuit, and the ballast resistor is connected in series in the circuit.

[0028] In the fluorine-containing gas degradation device based on warm plasma nozzle arc, the rated voltage of the DC power supply is 10kV, the rated current is 0.2A, and the resistance of the ballast resistor is 35kΩ.

[0029] In the fluorine-containing gas degradation device based on warm plasma nozzle arc, the inert gas includes Ar or N2, the fluorine-containing gas includes SF6 or CF4, and the active gas includes H2, O2 or H2O.

[0030] The degradation method of the fluorine-containing gas degradation device based on the warm plasma nozzle arc comprises the following steps:

[0031] Open the inert gas source and introduce a predetermined flow of inert gas into the reaction space;

[0032] Turn on the DC power supply to ignite an arc in the reaction space to form warm plasma;

[0033] The fluorine-containing gas from the fluorine-containing gas input line and the active gas from the active gas input line are mixed and introduced into the reaction gas inlet, and the fluorine-containing gas and the corresponding active gas are introduced to decompose the fluorine-containing gas by utilizing the ionization characteristics of the warm plasma;

[0034] After the fluorine-containing gas decomposes, it passes through the Laval nozzle and the acid gas adsorbent with the active gas, and the acid gas adsorbent absorbs the generated acid gas;

[0035] The buffer tank is connected to the tail gas outlet. The tail gas is discharged through the tail gas outlet after being tested by the exhaust gas detection device and meeting the standards. The gas that does not meet the standards is circulated into the reaction space through the circulation pump until it meets the standards and is discharged.

[0036] Compared with the existing technology, the present invention has the following advantages: the present invention adopts warm plasma degradation technology, which has a higher reaction temperature, more thorough degradation, and greater processing capacity; adopts a Laval nozzle structure to accelerate the gas cooling rate, inhibit the occurrence of composite reactions, and inhibit the occurrence of composite reactions by combining active gases with fluorine-containing components; the present invention adopts a constant current source, and compared with an AC power supply, the DC source has a simpler arc striking principle and more stable arc energy; the exhaust gas circulation system uses a circulation pump to circulate the exhaust gas for degradation, which can improve the degradation rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Various other advantages and benefits of the present invention will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are intended only to illustrate preferred embodiments and are not to be construed as limiting the present invention. It should be understood that the drawings described below are merely examples of the present invention, and that those skilled in the art will be able to derive other drawings from these drawings without inventive effort. Throughout the drawings, identical reference numerals are used to denote identical components.

[0038] In the attached figure:

[0039] Figure 1 2 is a schematic structural diagram of a fluorine-containing gas degradation device based on a warm plasma nozzle arc according to one embodiment of the present invention;

[0040] Figure 2 1 is a schematic structural diagram of a warm plasma generator of a fluorine-containing gas degradation device based on a warm plasma nozzle arc according to an embodiment of the present invention.

[0041] The present invention will be further explained below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0042] Specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0043] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the invention. The scope of protection of the present invention shall be as defined in the attached claims.

[0044] To facilitate understanding of the embodiments of the present invention, further explanation will be given below using specific embodiments as examples in conjunction with the accompanying drawings, and the accompanying drawings do not constitute a limitation on the embodiments of the present invention.

[0045] For better understanding, Figures 1 to 2 As shown, the fluorine-containing gas degradation device based on the warm plasma nozzle arc includes:

[0046] A gas control input system comprising,

[0047] The fluorine-containing gas input circuit includes a fluorine-containing gas source, a gas valve 1 and a mass flow meter 2 connected in sequence to provide a fluorine-containing gas flow rate.

[0048] The active gas input circuit includes an active gas source, a gas valve and a mass flow meter connected in sequence to provide the active gas flow.

[0049] an inert gas input circuit, comprising an inert gas source, a gas valve, and a mass flow meter connected in sequence to provide an inert gas flow rate;

[0050] A warm plasma generator 3, comprising:

[0051] Insulation base,

[0052] The anode 3.2 is inserted into the insulating base and is provided with a reaction gas inlet 3.1. The fluorine-containing gas from the fluorine-containing gas input line and the active gas from the active gas input line are mixed and introduced into the reaction gas inlet 3.1.

[0053] The cathode 3.4 is fixedly connected to the insulating base and surrounds the anode 3.2. The cathode 3.4 is provided with an inert gas inlet 3.5. The inert gas from the inert gas input line is introduced into the inert gas inlet 3.5.

[0054] A ceramic tube is provided through the cathode 3.4 and faces the anode 3.2. The ceramic tube, cathode 3.4 and anode 3.2 form a reaction space for generating warm plasma. The ceramic tube is provided with a Laval nozzle 3.7.

[0055] The harmless treatment system includes:

[0056] an acid gas adsorbent 3.8 disposed in the rear portion of the ceramic tube to absorb the acid gas generated by the reaction;

[0057] A buffer tank 6 is connected to the ceramic tube and is provided with an exhaust gas outlet 7 for discharging degradation exhaust gas.

[0058] A circulation pump 8 has one end connected to the buffer tank 6 and the other end connected to the reaction gas inlet 3.1 to refill the anode 3.2 for reaction.

[0059] In a preferred embodiment of the fluorine-containing gas degradation device based on warm plasma nozzle arc, the end of the anode 3.2 has at least one first inclined surface, and the cathode 3.4 has a second inclined surface parallel to and opposite to the first inclined surface.

[0060] In a preferred embodiment of the fluorine-containing gas degradation device based on warm plasma nozzle arc, the anode 3.2 is a hollow structure.

[0061] In a preferred embodiment of the fluorine-containing gas degradation device based on warm plasma nozzle arc, the cathode 3.4 has a downwardly inclined annular channel, and the annular channel is connected to the inert gas inlet 3.5 to form a spiral input gas path.

[0062] In a preferred embodiment of the fluorine-containing gas degradation device based on the warm plasma nozzle arc, the warm plasma generator 3 further includes a sealing flange 3.6 connecting the cathode 3.4 and the ceramic tube.

[0063] In a preferred embodiment of the fluorine-containing gas degradation device based on warm plasma nozzle arc, the insulating base is a polytetrafluoroethylene base 3.3.

[0064] In a preferred embodiment of the fluorine-containing gas degradation device based on the warm plasma nozzle arc, the positive and negative electrodes of the DC power supply 5 are respectively connected to the anode 3.2 and the cathode 3.4 to form a circuit, and the ballast resistor 4 is connected in series in the circuit.

[0065] In a preferred embodiment of the fluorine-containing gas degradation device based on warm plasma nozzle arc, the rated voltage of the DC power supply 5 is 10 kV, the rated current is 0.2 A, and the resistance of the ballast resistor 4 is 35 kΩ.

[0066] In a preferred embodiment of the fluorine-containing gas degradation device based on warm plasma nozzle arc, the inert gas includes Ar or N2, the fluorine-containing gas includes SF6 or CF4, and the active gas includes H2, O2 or H2O.

[0067] In one embodiment, a fluorine-containing gas degradation device based on a warm plasma nozzle arc comprises:

[0068] A gas control input system comprising,

[0069] The fluorine-containing gas input circuit includes a fluorine-containing gas source, a gas valve and a mass flow meter connected in sequence.

[0070] The active gas input circuit includes an active gas source, a gas valve and a mass flow meter connected in sequence. The fluorine-containing gas and the active gas are mixed in the input circuit and then introduced into the warm plasma generator 3.

[0071] An inert gas input circuit, comprising an inert gas source, a gas valve, and a mass flow meter connected in sequence;

[0072] A warm plasma generator 3, comprising:

[0073] The connecting device includes a polytetrafluoroethylene base 3.3 for connecting the positive and negative electrodes, a sealing flange 3.6 for connecting the cathode 3.4 and the Laval nozzle 3.7 pipeline,

[0074] The DC power supply 5, the positive and negative poles of the power supply are connected to the anode 3.2 and the cathode 3.4 respectively through the ballast resistor 4,

[0075] The ballast resistor 4 is connected in series in the circuit to play a protective role.

[0076] Anode 3.2 is hollow inside and connected to reaction gas inlet 3.1. Fluorine-containing gas and active gas are fed into warm plasma generator 3 through anode 3.2.

[0077] The cathode 3.4 is connected to an inert gas input line, into which inert gas is introduced to maintain the combustion of the plasma and blow out the arc.

[0078] The ceramic tube is fixed to the nozzle by a sealing flange 3.6 and is provided with a Laval nozzle 3.7 to increase the gas cooling rate and provide a reaction space;

[0079] The harmless treatment system includes:

[0080] Acid gas adsorbent 3.8 is placed at the end of the ceramic tube to absorb the acid gas produced during the reaction.

[0081] The buffer tank 6 is connected between the outlet of the ceramic tube and the circulation pump 8 to buffer the pressure fluctuation of the system. The side end is connected to the tail gas outlet 7 to discharge the tail gas.

[0082] The circulation pump 8 is connected between the buffer tank 6 and the reaction gas inlet 3.1, and refills the degradation gas that does not meet the standard into the anode 3.2 for reaction.

[0083] The tail gas outlet 7 is connected to one side of the buffer tank 6 and can discharge the degradation tail gas.

[0084] The exhaust gas monitoring device is connected to the exhaust gas outlet 7 and can sample and detect the exhaust gas.

[0085] In one embodiment, the inert gas is Ar.

[0086] In one embodiment, the ballast resistor 4 has an adjustable resistance value and plays a protective role in the circuit.

[0087] In one embodiment, the anode 3.2 and cathode 3.4 are both made of copper electrodes.

[0088] In one embodiment, the ceramic tube material is an acid-resistant ceramic tube.

[0089] In one embodiment, when the reactive gas and the fluorine-containing gas are H 2 and SF 6 , the mixing ratio is 4:1.

[0090] In one embodiment, when the fluorine-containing gas and the reactive gas are SF6 and H2 respectively, the generated products are HF and S.

[0091] In one embodiment, the exhaust gas detection device includes an X-ray diffraction analyzer, a chromatographic analyzer, and a spectrum analyzer.

[0092] In one embodiment, the cathode 3.4 and the anode 3.2 are both copper electrodes, which have good electrical conductivity and ablation resistance.

[0093] In one embodiment, the inert gas inlet 3.5 is a spiral air inlet. The spiral air inlet generates a tangential airflow, which is beneficial to the rotation of the arc of the nozzle 3.7. The rotation of the arc can reduce the ablation of the electrode.

[0094] In one embodiment, the main material of the polytetrafluoroethylene base 3.3 is polytetrafluoroethylene, and its main function is to be placed between the anode and cathode to provide insulation and fixation.

[0095] In one embodiment, the sealing flange 3.6 connects the cathode 3.4 and the acid-resistant ceramic tube to seal the entire reaction device. Compared with polytetrafluoroethylene, the sealing flange 3.6 is more resistant to high temperatures.

[0096] In one embodiment, the acid-resistant ceramic tube is connected to the sealing flange 3.6 to converge the arc and provide a gas ionization field. At the same time, a Laval nozzle 3.7 is provided inside. The main function of the Laval nozzle 3.7 is to accelerate gas cooling and inhibit the occurrence of fluorine-containing gas complex reactions.

[0097] Optionally, the acid-resistant ceramic tube may be replaced by a quartz tube. Compared with the acid-resistant ceramic tube, the quartz tube is more resistant to high temperatures, but is not acid-resistant and has a relatively short service life.

[0098] In one embodiment, the acid gas adsorbent 3.8 is placed at the tail end of the acid-resistant ceramic tube to adsorb the reaction gas passing through the Laval nozzle 3.7 as part of the tail gas treatment.

[0099] Optionally, in addition to the acid gas adsorbent 3.8, an alkaline water pool may be provided at the gas outlet, and the gas may be passed into the alkaline water pool to absorb the generated acid gas.

[0100] In one embodiment, using Ar as a carrier gas makes arc burning more stable and requires less power to maintain arc discharge. Moreover, Ar, as an inert gas, does not react with the fluorine-containing gas to generate other byproducts.

[0101] Alternatively, N2 can be used as the inert gas. Nitrogen is cheaper and more readily available, but N and F will combine with each other during the cooling process to generate a greenhouse gas NF3, the direct emission of which will cause harm to the environment.

[0102] In one embodiment, the active gas may be H2, O2, H2O, etc., which react with the ionization products of the fluorine-containing gas under the action of the warm plasma to generate acidic gas, thereby inhibiting the occurrence of the fluorine-containing gas recombination reaction.

[0103] Optionally, when the active gas is an oxygen-containing gas, O radicals will combine with C or S to generate CO during the cooling process. x F y , CO x or SO x F y , SO x Gaseous products such as chlorinated hydrocarbons can be absorbed by the acid gas adsorbent 3.8.

[0104] In one embodiment, each gas input line is equipped with a gas source, a gas valve 1, and a respective mass flowmeter 2. The mass flowmeter regulates the gas input flow rate. The primary function of the inert gas is to provide the necessary gas environment for arc combustion and to blow the arc out of the nozzle. Fluorine-containing gas and reactive gas are introduced into the reaction gas inlet 3.1 in a specific ratio, then enter the nozzle arc region through the anode for ionization.

[0105] In one embodiment, the warm plasma generating system includes a warm plasma generator 3, a ballast resistor 4, and a DC power supply 5. The positive and negative electrodes of the DC power supply 5 are connected to the anode 3.2 and cathode 3.4 of the warm plasma generator via the ballast resistor 4, providing an energy source for the arc device. The DC power supply typically operates as a constant current source of 0.2A with a maximum voltage of 10kV. The ballast resistor 4, which has a typical operating resistance of 35kΩ, is connected between the positive electrode of the power supply and the anode 3.2 of the warm plasma generator to protect the circuit. The warm plasma generating device includes a reaction gas inlet 3.1, an anode 3.2, a polytetrafluoroethylene base 3.3, a cathode 3.4, an argon gas inlet 3.5, a sealing flange 3.6, and a Laval nozzle 3.7. The above components are connected in sequence to form a warm plasma generator.

[0106] In one embodiment, the harmless treatment system includes an acid gas adsorbent 3.8, a buffer tank 6, an exhaust gas outlet 7, a circulation pump 8, and an exhaust gas detection device. The acid gas adsorbent 3.8 is placed at the tail end of the acid-resistant ceramic tube, and its function is to absorb the acid gas generated after the ionization of the fluorine-containing gas and suppress the occurrence of the composite reaction. The buffer tank 6 is connected to the tail end of the acid-resistant ceramic tube. The gas is adsorbed by the acid gas adsorbent and then passed into the buffer tank 6. The buffer tank 6 is connected to the exhaust gas outlet 7 and the circulation pump 8. The main function of the buffer tank 6 is to balance the pressure in the reaction space. The reaction gas can be collected and tested at the exhaust gas outlet 7, and can be directly discharged after passing the test. The reaction gas can also be extracted from the buffer tank 6 by the circulation pump 8 and passed into the warm plasma device again for a cyclic reaction until it is discharged after passing the test. The exhaust gas monitoring device can be used for detection by a chromatograph and a spectrometer, and the exhaust gas can be directly discharged after meeting the standard.

[0107] The degradation method of the fluorine-containing gas degradation device based on the warm plasma nozzle arc comprises the following steps:

[0108] Open the inert gas source and introduce a predetermined flow of inert gas into the reaction space;

[0109] Turn on the DC power supply 5 to ignite an arc in the reaction space to form a warm plasma;

[0110] The fluorine-containing gas from the fluorine-containing gas input line and the reactive gas from the reactive gas input line are mixed and introduced into the reaction gas inlet 3.1, where the fluorine-containing gas and the corresponding reactive gas are introduced to decompose the fluorine-containing gas by utilizing the ionization characteristics of the warm plasma;

[0111] After decomposition, the fluorine-containing gas and the active gas pass through the Laval nozzle 3.7 and the acid gas adsorbent 3.8, and the acid gas adsorbent 3.8 absorbs the generated acid gas;

[0112] The buffer tank 6 is connected to the tail gas outlet 7. The tail gas is discharged through the tail gas outlet 7 after being tested by the exhaust gas detection device to meet the standards. The gas that does not meet the standards is circulated into the reaction space through the circulation pump 8 until it meets the standards and is discharged.

[0113] In one embodiment, the degradation method of the fluorine-containing gas degradation device based on the warm plasma nozzle arc includes:

[0114] Initially, Ar is introduced into the warm plasma generator, serving as the arc-burning gas medium and the power source for the arc's motion. A DC power supply 5 acts on both the cathode and anode to provide stable plasma energy. Once the arc stabilizes, a predetermined ratio of fluorine-containing gas and reactive gas is introduced through the reaction gas inlet. Under the action of the warm plasma, the fluorine-containing gas ionizes and reacts with the reactive gas, rapidly cooling through the Laval nozzle 3.7. The acidic gas products are then adsorbed by the acid gas adsorbent 3.8. The adsorbed gas is then passed through the tail of an acid-resistant ceramic tube into a buffer tank 6. Once the exhaust gas passes inspection, it is discharged through the exhaust outlet 7. Any unqualified gas is returned to the warm plasma generator by a circulation pump 8 for ionization and degradation.

[0115] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments and application fields. The above-mentioned specific embodiments are merely illustrative and instructive, and are not restrictive. A person skilled in the art, guided by this specification and without departing from the scope of protection of the claims of the present invention, may also devise various forms, all of which fall within the scope of protection of the present invention.

Claims

1. A fluorine-containing gas degradation device based on a warm plasma nozzle arc, characterized in that: It includes: A gas control input system comprising: a fluorine-containing gas input circuit, comprising a fluorine-containing gas source, a gas valve, and a mass flow meter connected in sequence to provide a fluorine-containing gas flow rate; an active gas input circuit, comprising an active gas source, a gas valve, and a mass flow meter connected in sequence to provide an active gas flow rate; an inert gas input circuit, comprising an inert gas source, a gas valve, and a mass flow meter connected in sequence to provide an inert gas flow rate; A warm plasma generator comprising: Insulation base; an anode, which is inserted into the insulating base and provided with a reaction gas inlet, into which the fluorine-containing gas from the fluorine-containing gas input line and the active gas from the active gas input line are mixed and then introduced; a cathode fixedly connected to the insulating base and surrounding the anode, wherein the cathode is provided with an inert gas inlet, and an inert gas from an inert gas input line is introduced into the inert gas inlet; a ceramic tube passing through the cathode and facing the anode, wherein the ceramic tube, the cathode and the anode constitute a reaction space for generating warm plasma, and the ceramic tube is provided with a Laval nozzle; The harmless treatment system includes: an acidic gas adsorbent disposed in the tail portion of the ceramic tube to absorb the acidic gas generated by the reaction; a buffer tank connected to the ceramic tube, the buffer tank being provided with an exhaust gas outlet for discharging degradation exhaust gas; A circulation pump has one end connected to the buffer tank and the other end connected to the reaction gas inlet so as to refill the anode with gas for reaction.

2. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: Preferably, the end of the anode has at least one first inclined surface, and the cathode has a second inclined surface parallel to and opposite to the first inclined surface.

3. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: The anode has a hollow structure.

4. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: The cathode has an annular channel inclined downward, and the annular channel is connected to the inert gas inlet to form a spiral input gas path.

5. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: The warm plasma generator further includes a sealing flange connecting the cathode and the ceramic tube.

6. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: The insulating base is a polytetrafluoroethylene base.

7. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: The positive and negative electrodes of the DC power supply are respectively connected to the anode and cathode to form a circuit, and the ballast resistor is connected in series in the circuit.

8. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 7, characterized in that: The rated voltage of the DC power supply is 10 kV, the rated current is 0.2 A, and the resistance of the ballast resistor is 35 kΩ.

9. The fluorine-containing gas degradation device based on warm plasma nozzle arc according to claim 1, characterized in that: The inert gas includes Ar or N2, the fluorine-containing gas includes SF6 or CF4, and the active gas includes H2, O2 or H2O.

10. The degradation method of the fluorine-containing gas degradation device based on the warm plasma nozzle arc according to any one of claims 1 to 9, characterized in that: It includes the following steps, Open the inert gas source and introduce a predetermined flow of inert gas into the reaction space; Turn on the DC power supply to ignite an arc in the reaction space to form warm plasma; The fluorine-containing gas from the fluorine-containing gas input line and the active gas from the active gas input line are mixed and introduced into the reaction gas inlet, and the fluorine-containing gas and the corresponding active gas are introduced to decompose the fluorine-containing gas by utilizing the ionization characteristics of the warm plasma; After the fluorine-containing gas decomposes, it passes through the Laval nozzle and the acid gas adsorbent with the active gas, and the acid gas adsorbent absorbs the generated acid gas; The buffer tank is connected to the tail gas outlet. The tail gas is discharged through the tail gas outlet after being tested by the exhaust gas detection device and meeting the standards. The gas that does not meet the standards is circulated into the reaction space through the circulation pump until it meets the standards and is discharged.

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