High-flux low-temperature plasma discharge equipment and method for decomposing hydrogen sulfide

Abstract

The present invention relates to the field of plasma chemistry and discloses a high-flux low-temperature plasma discharge device and a method for decomposing hydrogen sulfide, comprising: a first cavity (1), a second cavity (2) nested inside the first cavity (1); a high-voltage electrode (3) and a grounding electrode (4) arranged in the first cavity (1), and a blocking medium, wherein the blocking medium is arranged on the outer surface of the high-voltage electrode (3) and / or the grounding electrode (4). The high-flux low-temperature plasma discharge device provided by the present invention has the advantages of high hydrogen sulfide conversion rate, low energy consumption, and the ability to achieve large-flow hydrogen sulfide treatment.

Description

Technical Field

[0001] The present invention relates to the field of plasma chemistry, and in particular to a high-flux low-temperature plasma discharge device and a method for decomposing hydrogen sulfide. Background Art

[0002] Hydrogen sulfide (H2S) is a highly toxic, foul-smelling acidic gas that not only corrodes metals and other materials, but also poses a health hazard and pollutes the environment. Currently, large and medium-sized refineries in my country use the traditional Claus process to treat H2S-containing tail gas and recover sulfur. This method only recovers the sulfur from the hydrogen sulfide, while converting the precious hydrogen into water. From the perspective of comprehensive resource utilization, hydrogen resources are not effectively utilized in traditional hydrogen sulfide recovery processes.

[0003] Therefore, decomposing hydrogen sulfide into sulfur and hydrogen has gradually become a technical field that domestic and foreign scientific researchers focus on.

[0004] Currently, the main methods for decomposing hydrogen sulfide include high-temperature decomposition, electrochemical methods, photocatalytic methods, and low-temperature plasma methods. Among these methods, high-temperature thermal decomposition is relatively mature in industrial technology. However, thermal decomposition of hydrogen sulfide is strongly dependent on reaction temperature and is subject to thermodynamic equilibrium constraints. Even at reaction temperatures above 1000°C, the conversion rate of hydrogen sulfide is only 20%. Furthermore, high temperatures place high demands on reactor materials, which increases operating costs. Furthermore, the low conversion rate of thermal decomposition requires large amounts of hydrogen sulfide gas to be separated from the exhaust gas and recirculated within the system, which reduces device efficiency and increases energy consumption, hindering its large-scale industrial application. While membrane technology can effectively separate products, thereby breaking equilibrium constraints and increasing hydrogen sulfide conversion, the thermal decomposition temperature often exceeds the membrane's maximum heat resistance, damaging the membrane material structure. Electrochemical methods suffer from disadvantages such as multiple steps, severe equipment corrosion, poor reaction stability, and low efficiency. Photocatalytic decomposition of hydrogen sulfide primarily draws on research on photocatalytic water splitting, with research focusing on the development of efficient semiconductor photocatalysts. Using solar energy to decompose hydrogen sulfide is a relatively economical method with advantages such as low energy consumption, mild reaction conditions, and simple operation. However, this method has problems such as small processing capacity, low catalytic efficiency, and easy catalyst deactivation.

[0005] Compared to other decomposition methods, the low-temperature plasma method offers advantages such as simple operation, compact size, and high energy efficiency. Furthermore, the reactions involved are highly controllable, allowing for flexible application in low-volume, difficult-to-centralize processes. Furthermore, due to its high energy density and shortened reaction time, it can effectively decompose hydrogen sulfide at relatively low temperatures, making it suitable for sites of varying scale, dispersed layouts, and variable production conditions. Furthermore, while recovering sulfur, the low-temperature plasma method also recovers hydrogen resources, enabling the resourceful utilization of hydrogen sulfide.

[0006] At present, researchers at home and abroad have conducted extensive research on the technology of decomposing hydrogen sulfide by low-temperature plasma. The discharge forms used mainly include glow discharge, corona discharge, sliding arc discharge, microwave plasma, radio frequency plasma and dielectric barrier discharge.

[0007] CN102408095A uses dielectric barrier discharge and photocatalyst to synergistically decompose hydrogen sulfide. The method is to fill a solid catalyst with photocatalytic activity in the plasma zone. However, this method has the disadvantage that sulfur produced by the decomposition of hydrogen sulfide will be deposited under the catalyst bed.

[0008] CN103204466A discloses a temperature-controlled hydrogen sulfide decomposition device and method. This device features a metal central electrode and a temperature-controlled circulating liquid grounding electrode. Temperature control of the liquid grounding electrode allows for continuous and stable hydrogen sulfide decomposition. Separately, CN103204467A discloses a device and method for the continuous and stable decomposition of hydrogen sulfide to produce hydrogen. This prior art features a metal central electrode and a temperature-controlled circulating liquid grounding electrode. The liquid grounding electrode controls the temperature, and the feedstock is fed circumferentially and passes through the discharge zone in a spiral pattern in the opposite direction of the axial direction, allowing the generated sulfur to be promptly centrifuged and separated. However, in order to ensure that hydrogen sulfide is decomposed as fully as possible in the methods disclosed in CN103204466A and CN103204467A, it is necessary to control the flow rate of hydrogen sulfide so that its residence time in the reactor inner cylinder is longer and to control the size of the inner cylinder so that more electricity is obtained per unit volume of gas in the inner cylinder. Moreover, since the current existing technology cannot provide a power supply with higher power, even if the residence time of hydrogen sulfide is controlled longer and the size of the inner cylinder is controlled so that more electricity is obtained per unit volume of gas in the inner cylinder, the methods disclosed in CN103204466A and CN103204467A can only achieve a maximum hydrogen sulfide conversion rate of approximately 20%. Moreover, when the maximum hydrogen sulfide conversion rate reaches approximately 20%, the energy consumption of the hydrogen sulfide decomposition reaction is quite high, which is not suitable for large-scale industrial applications. Furthermore, the methods disclosed in CN103204466A and CN103204467A also have the defect that the types of liquid grounding electrodes that can be used are extremely limited. The salt solutions disclosed therein can generally only maintain the temperature of the reactor below 100°C. Below 100°C, elemental sulfur is generally in a solid state, which can easily cause blockage of the reactor. Summary of the Invention

[0009] The purpose of the present invention is to overcome the defects of the prior art in decomposing hydrogen sulfide into hydrogen and elemental sulfur, such as low hydrogen sulfide conversion rate, high energy consumption and inability to achieve large-flow hydrogen sulfide treatment, and to provide a new high-flux low-temperature plasma discharge device and a method for decomposing hydrogen sulfide using the discharge device.

[0010] In order to achieve the above-mentioned object, a first aspect of the present invention provides a high-flux low-temperature plasma discharge device, the discharge device comprising:

[0011] a first cavity, wherein a first inlet and a first outlet are respectively provided on the first cavity;

[0012] a second cavity, the second cavity being nested inside the first cavity and having a second inlet and a second outlet respectively provided on the second cavity;

[0013] a high-voltage electrode and a grounding electrode, the high-voltage electrode and the grounding electrode being disposed in the first cavity, the high-voltage electrode and the grounding electrode being plural in number to form a layer structure of which the number is ≥1, and in each layer structure, the high-voltage electrode and the grounding electrode are spaced apart from each other;

[0014] a blocking medium, the blocking medium being arranged on an outer surface of the high voltage electrode and / or the ground electrode;

[0015] The distance between the high-voltage electrode and the ground electrode is L1, the thickness of the blocking medium is D1, L2=L1-D1, and the ratio between L2 and D1 is (0.1~150):1, preferably (0.2~100):1; more preferably (0.5~80):1; further preferably (0.5~50):1.

[0016] In the present invention, D1 represents the total thickness of the barrier medium between the two nearest adjacent high-voltage electrodes and the ground electrode; L1 represents the distance between the nearest high-voltage electrode and the ground electrode.

[0017] The aforementioned plasma discharge equipment provided by the present invention is a jacketed dielectric barrier discharge equipment, whose basic structure mainly includes a high-voltage electrode, a grounding electrode and a barrier medium. The jacketed structure enables the heat-conducting medium to circulate heating or cooling of the discharge equipment, thereby realizing flexible temperature control of the discharge area.

[0018] In particular, the plasma discharge device having the specific structure of the present invention can significantly improve the conversion rate of hydrogen sulfide compared with the prior art.

[0019] Preferably, in two adjacent layer structures, the center of the electrode in the upper layer structure is aligned with or offset from the center of the electrode in the lower layer structure.

[0020] Preferably, the gap between two adjacent layer structures is greater than 0 and less than or equal to 100 mm.

[0021] In the present invention, in each layer structure, it is preferred that each electrode in the same layer structure is parallel to each other.

[0022] Preferably, in each of the layer structures, the gap between two adjacent electrodes is greater than 0 and less than or equal to 100 mm.

[0023] In the present invention, unless otherwise specified, “gap” refers to the shortest distance.

[0024] In each layer structure, the high-voltage electrode and the grounding electrode are arranged at intervals, which means that a grounding electrode is inserted between two adjacent high-voltage electrodes in each layer structure, thereby forming a high-voltage-grounding mixed layer that alternately contains high-voltage electrodes and grounding electrodes.

[0025] Preferably, the number of layers of the high-voltage-grounding mixed layer is at least one, and each of the high-voltage-grounding mixed layers is arranged in parallel. The arrangement includes three different arrangements. The first is: the grounding electrodes in two adjacent high-voltage-grounding mixed layers are parallel to each other; the second is: the grounding electrodes in two adjacent high-voltage-grounding mixed layers are perpendicular to each other; the third is: the grounding electrodes in two adjacent high-voltage-grounding mixed layers are at an angle greater than 0° and less than 90°. As long as the arrangement can generate a uniform electric field in the first cavity. In a particularly preferred case, the grounding electrodes in two adjacent high-voltage-grounding mixed layers of the present invention are arranged parallel to each other or perpendicular to each other.

[0026] In a particularly preferred case, the grounding electrodes in two adjacent high-voltage-grounding mixed layers of the present invention are parallel to each other; further preferably, the two adjacent high-voltage-grounding mixed layers are arranged so that a high-voltage electrode is directly below the grounding electrode in the upper high-voltage-grounding mixed layer, or the two adjacent high-voltage-grounding mixed layers are arranged so that a grounding electrode is directly below the grounding electrode in the upper high-voltage-grounding mixed layer, or the center line of an adjacent group of high-voltage electrodes and grounding electrodes in the upper high-voltage-grounding mixed layer has a high-voltage electrode or a grounding electrode in the adjacent lower high-voltage-grounding mixed layer.

[0027] The present invention has no particular limitation on the specific form of the aforementioned second cavity. However, in order to achieve better hydrogen sulfide decomposition efficiency, the present invention provides several preferred specific embodiments of the second cavity below.

[0028] The heat-conducting medium contained in the second cavity of the present invention is capable of maintaining the required temperature of the first cavity. Specifically, the structure of the present invention enables the heat-conducting medium to circulate within the shell, maintaining the entire discharge device within a certain temperature range while ensuring discharge intensity. This allows the generated sulfur to flow out of the discharge device in liquid form, effectively preventing the solidification of the sulfur generated by the decomposition of hydrogen sulfide. This allows the decomposition process to be sustained, stable, and operate over a long period of time while achieving a high conversion rate.

[0029] In a particularly preferred embodiment, the ratio between L2 and the length L3 of the discharge tube is independently 1:(2-1500), preferably 1:(20-500), and more preferably 1:(20-300). The length L3 of the discharge tube is the effective length for a single high-voltage electrode and a single ground electrode to participate in the discharge. When the ratio between L2 and the length L3 of the discharge tube is independently 1:(2-1500), preferably 1:(20-500), and more preferably 1:(20-300), the energy consumption of decomposing hydrogen sulfide gas can be significantly reduced.

[0030] Preferably, the high-voltage electrodes are connected in parallel with each other.

[0031] Preferably, the ground electrodes are connected in parallel with each other.

[0032] According to a preferred embodiment (embodiment 1), the barrier medium is provided on the outer surface of the high-voltage electrode.

[0033] According to another preferred embodiment (embodiment 2), the barrier medium is provided on the outer surface of the ground electrode.

[0034] According to another preferred embodiment (embodiment 3), the blocking medium is provided on outer surfaces of the high-voltage electrode and the ground electrode.

[0035] In the aforementioned Specific Embodiments 1 and 2, the device of the present invention can achieve single-dielectric barrier discharge. When single-dielectric barrier discharge is used, the aforementioned barrier dielectric thickness D1 is the thickness of the barrier dielectric on the corresponding high-voltage electrode or ground electrode. It should be further explained that because the electric field exists between the ground electrode and the high-voltage electrode, the thickness here represents the thickness of the barrier dielectric on the corresponding high-voltage electrode or ground electrode.

[0036] In the aforementioned embodiment 3 of the present invention, the device of the present invention can realize dual-dielectric barrier discharge. When dual-dielectric barrier discharge is realized, the thickness D1 of the aforementioned barrier dielectric is the sum of the thicknesses of the barrier dielectrics on the corresponding high-voltage electrode and the ground electrode. Because the electric field exists between the ground electrode and the high-voltage electrode, the sum of the thicknesses here represents the sum of the thicknesses of the barrier dielectrics on the corresponding high-voltage electrode and the ground electrode.

[0037] The present invention has no special restrictions on the fixing form of the blocking medium and the high-voltage electrode and / or the grounding electrode. The blocking medium can be fixed on the outer surface of the high-voltage electrode and / or the grounding electrode in any fixable manner, or the blocking medium can also be coated on the outer surface of the high-voltage electrode or the grounding electrode in the form of a coating.

[0038] Preferably, the material forming the barrier dielectric is an electrically insulating material, more preferably, at least one selected from glass, ceramic, enamel, polytetrafluoroethylene, and mica. The glass may be quartz glass or hard glass; the material forming the barrier dielectric may also be other metal or non-metal composite materials designed for high-voltage electrical insulation. The ceramic may be alumina ceramic.

[0039] Preferably, the device of the present invention further comprises a grounding wire, one end of which is electrically connected to the grounding electrode.

[0040] Preferably, the first inlet is provided at an upper portion of the first cavity, and the first outlet is provided at a bottom portion of the first cavity.

[0041] Preferably, the second inlet is provided at a lower portion of the second cavity, and the second outlet is provided at an upper portion of the second cavity.

[0042] According to a preferred embodiment, at least one of the plurality of high-voltage electrodes and the plurality of ground electrodes is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0043] According to another preferred embodiment, each of the high-voltage electrodes and each of the grounding electrodes is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0044] According to another preferred embodiment, each of the high-voltage electrodes is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0045] According to another preferred embodiment, each of the ground electrodes is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0046] The sizes of the high-voltage electrodes of the present invention may be the same or different. Preferably, the sizes of the high-voltage electrodes are the same.

[0047] The sizes of the ground electrodes of the present invention may be the same or different. Preferably, the sizes of the ground electrodes are the same.

[0048] The aforementioned same size in the present invention means that the size and shape are exactly the same.

[0049] Preferably, each of the high-voltage electrodes and each of the grounding electrodes is cylindrical. It should be noted that the present invention is not particularly limited to cylindrical shapes for the high-voltage electrodes and the grounding electrodes; for example, they may also be serpentine, fin-shaped, S-shaped, wavy, threaded, or mace-shaped (i.e., having a protruding structure on the sidewall).

[0050] Preferably, when each of the high-voltage electrodes and each of the grounding electrodes are cylindrical, the diameters of the high-voltage electrodes and the grounding electrodes are independently 0.1 to 100 mm, more preferably 0.5 to 50 mm.

[0051] Preferably, the height-to-diameter ratio of the high-voltage electrode and the ground electrode is independently (5-600):1, preferably (10-400):1.

[0052] The inner diameter in the present invention refers to the diameter.

[0053] Preferably, the material forming the grounding electrode is selected from graphite tubes, graphite powder, metal tubes, metal rods, metal powder or graphite rods. The grounding electrode of the present invention generates a larger micro-discharge current under the condition of a certain injection power, which is more conducive to the bond-breaking decomposition reaction of hydrogen sulfide. The metal tubes and metal rods in the materials forming the grounding electrode may include elemental metal tubes, elemental metal rods, alloy metal tubes, and alloy metal rods. The inventors of the present invention have found that using a solid conductive material as the grounding electrode of the device of the present invention can significantly improve the conversion rate of hydrogen sulfide when the device provided by the present invention is used to carry out a hydrogen sulfide decomposition reaction.

[0054] The material forming the high-voltage electrode is a conductive material. Preferably, the material forming the high-voltage electrode is selected from at least one of a graphite tube, graphite powder, a metal rod, a metal tube, metal powder, a graphite rod, and a mechanical mixture of one or more of these. The metal rods and metal tubes may include elemental metal rods, alloy metal rods, elemental metal tubes, and alloy metal tubes. The so-called metal powder may include elemental metal powder, alloy metal powder, and a mechanical mixture of elemental and / or alloy metal powders. The material forming the high-voltage electrode of the present invention may be other rod-shaped and tubular materials having conductive properties.

[0055] The metal powder of the present invention means that when a barrier medium is wrapped on the outer surface of a grounding electrode and / or a high-voltage electrode, the barrier medium can be arranged in a hollow tubular form, and metal powder can be filled in the middle of the barrier medium to form a grounding electrode and / or a high-voltage electrode wrapped in a barrier medium; the metal powder can be a single metal powder, an alloy metal powder, or a mechanical mixture of single metal powders and / or alloy metal powders.

[0056] The graphite powder of the present invention indicates that when a blocking medium is wrapped on the outer surface of a grounding electrode and / or a high-voltage electrode, the blocking medium can be arranged in a hollow tubular form, and graphite powder can be filled in the middle of the blocking medium to form a grounding electrode and / or a high-voltage electrode wrapped with a blocking medium.

[0057] The present invention can maintain the temperature of the discharge device with a sleeve structure at, for example, 119-444.6° C. by introducing a heat-conducting medium into the area between the second cavities, thereby ensuring that the sulfur generated by the decomposition of hydrogen sulfide flows out of the discharge area in liquid form.

[0058] The device of the present invention may also be loaded with a catalyst capable of catalyzing the decomposition of hydrogen sulfide into elemental sulfur and hydrogen. The catalyst is preferably loaded into the first cavity of the discharge device. The present invention has no particular requirements for the loading volume or type of the catalyst. The catalyst type may be, for example, any one or more of the catalysts disclosed in CN102408095A, CN101590410A, and CN103495427A.

[0059] The material forming the first cavity of the present invention may be, for example, a conductive metal material or an electrically insulating material that can provide structural support and is resistant to high temperatures, with the electrically insulating material being preferred.

[0060] In the present invention, there is no particular limitation on the material forming the second cavity, as long as the material forming the second cavity can withstand the set temperature of the thermally conductive medium. The material forming the second cavity of the present invention can be, for example, a conductive metal material or an electrically insulating material that can provide structural support and is resistant to high temperatures, with an electrically insulating material being preferred.

[0061] The following provides a preferred embodiment of decomposing hydrogen sulfide using the aforementioned device of the present invention:

[0062] Nitrogen is introduced into the first cavity of the device from the first inlet to clear the air in the discharge area, and the gas is drawn out from the first outlet. At the same time, a heat-conducting medium is introduced into the second cavity from the second inlet, and the introduced heat-conducting medium is drawn out from the second outlet. The temperature of the heat-conducting medium is maintained at the temperature required for the system reaction. Then, a raw gas containing hydrogen sulfide is introduced into the first cavity of the device from the first inlet. After the raw gas flow stabilizes, a high-voltage power supply (HV) is turned on, and a plasma discharge field is formed between the center electrode and the ground electrode by adjusting the voltage and frequency. The hydrogen sulfide gas is ionized in the discharge area and decomposed into hydrogen and elemental sulfur. The elemental sulfur produced by the discharge slowly flows down along the wall of the first cavity and flows out from the first outlet.

[0063] A second aspect of the present invention provides a method for decomposing hydrogen sulfide. The method is implemented in the high-flux, low-temperature plasma discharge device described in the first aspect of the present invention. The method comprises: grounding a ground electrode of the high-flux, low-temperature plasma discharge device, connecting a high-voltage electrode to a power source, performing dielectric barrier discharge, introducing a feed gas containing hydrogen sulfide from a reactor inlet into a first cavity of the high-flux, low-temperature plasma discharge device to perform a decomposition reaction of the hydrogen sulfide, and discharging a stream obtained after decomposition from a first outlet. Furthermore, a required temperature of the high-flux, low-temperature plasma discharge device is maintained by continuously introducing a heat-conducting medium into the second cavity of the high-flux, low-temperature plasma discharge device from a second inlet and discharging the heat-conducting medium from a second outlet.

[0064] Preferably, the dielectric barrier discharge conditions include: a discharge voltage of 2kV to 80kV, preferably 5kV to 30kV, more preferably 5kV to 20kV, and even more preferably 5kV to 15kV; a discharge frequency of 200 to 30,000 Hz, preferably 500 to 15,000 Hz, and even more preferably 500 to 13,000 Hz.

[0065] Preferably, the conditions for the hydrogen sulfide decomposition reaction include: a reaction temperature of 0 to 800°C, preferably 40 to 500°C, more preferably 119 to 444.6°C; a reaction pressure of 0 MPa to 0.6 MPa, preferably 0 MPa to 0.3 MPa; a residence time of the raw gas containing hydrogen sulfide in the discharge region of the high-flux low-temperature plasma discharge device of 1×10 -5 ~120s, preferably 2×10 -5 ~60s.

[0066] Preferably, the hydrogen sulfide decomposition reaction is carried out in the presence of a carrier gas, and the carrier gas is selected from at least one of nitrogen, hydrogen, helium, argon, water vapor, carbon monoxide, carbon dioxide, methane, ethane and propane; more preferably, the carrier gas is selected from at least one of hydrogen, argon, helium and nitrogen.

[0067] Particularly preferably, the carrier gas is selected from at least one of hydrogen, argon, helium and nitrogen.

[0068] Preferably, the content of hydrogen sulfide gas in the raw gas is such that the content of hydrogen sulfide gas at the first inlet of the high flux low temperature plasma discharge device is 1*10 -8 ~100 volume %; more preferably 10~100 volume %.

[0069] In the present invention, the raw gas does not include the aforementioned carrier gas of the present invention. The raw gas is pure hydrogen sulfide gas or industrial waste gas obtained in industrial production containing hydrogen sulfide and other gases. Although the raw gas may contain the same type of gas as the carrier gas defined in the present invention, the carrier gas defined in the present invention is a gas that is actively added to mix with the raw gas, and the method of the present invention can control the amount of carrier gas added as needed.

[0070] The device provided by the present invention also has the advantages of high hydrogen sulfide conversion rate, low energy consumption and the ability to achieve large-flow hydrogen sulfide treatment.

[0071] Furthermore, the device provided by the present invention can generate uniform and efficient dielectric barrier discharge, thereby directly decomposing hydrogen sulfide into hydrogen and sulfur with high efficiency.

[0072] In addition, the device provided by the present invention can achieve a continuous and stable hydrogen sulfide decomposition process at a significantly higher hydrogen sulfide conversion rate, and the device can achieve long-term operation. In addition, the device provided by the present invention can also be used in large-flow hydrogen sulfide treatment processes of various concentrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 It is a schematic cross-sectional structure diagram of a preferred specific embodiment of the high-flux low-temperature plasma discharge equipment provided by the present invention.

[0074] Figure 2 It is a schematic cross-sectional structure diagram of another preferred specific embodiment of the high-flux low-temperature plasma discharge device provided by the present invention.

[0075] Figure 3 yes Figure 1 The diagram shows a three-dimensional structure of the interior of the first cavity of a preferred embodiment of a high-flux low-temperature plasma discharge device.

[0076] Description of Reference Numerals

[0077] 1. First cavity 2. Second cavity

[0078] 11. First entrance 21. Second entrance

[0079] 12. First exit 22. Second exit

[0080] 3. High voltage electrode

[0081] 4. Grounding electrode

[0082] 5. Ground wire DETAILED DESCRIPTION

[0083] The endpoints of the ranges and any values ​​disclosed herein 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 endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0084] The following combination Figure 1 and Figure 2 The structure of a preferred embodiment of the high-flux low-temperature plasma discharge device of the present invention is provided, specifically:

[0085] The discharge equipment includes:

[0086] A first cavity 1, wherein a first inlet 11 and a first outlet 12 are respectively provided on the first cavity 1;

[0087] A second cavity 2, wherein the second cavity 2 is nested inside the first cavity 1, and a second inlet 21 and a second outlet 22 are respectively provided on the second cavity 2, and the heat transfer medium introduced through the second inlet 21 can be led out through the second outlet 22;

[0088] A high-voltage electrode 3 and a grounding electrode 4, wherein the high-voltage electrode 3 and the grounding electrode 4 are disposed in the first cavity 1, and each of the high-voltage electrode 3 and the grounding electrode 4 is provided in plurality to form a layer structure with a number ≥ 1, and in each layer structure, the high-voltage electrode 3 and the grounding electrode 4 are spaced apart;

[0089] a blocking medium, the blocking medium being arranged on the outer surface of the high-voltage electrode 3 and / or the ground electrode 4;

[0090] The distance between the high-voltage electrode 3 and the ground electrode 4 is L1, the thickness of the blocking medium is D1, L2=L1-D1, and the ratio between L2 and D1 is (0.1~150):1, preferably (0.2~100):1; more preferably (0.5~80):1; further preferably (0.5~50):1.

[0091] In this specific embodiment, a grounding electrode is inserted between two adjacent high-voltage electrodes in each layer structure, thereby forming a high-voltage-grounding mixed layer structure that alternately contains high-voltage electrodes and grounding electrodes; the number of layers of the high-voltage-grounding mixed layer structure is at least one, and each of the high-voltage-grounding mixed layer structures is arranged in parallel.

[0092] Specifically, the present invention Figure 1 and Figure 2 The main difference between them is the relative position of the electrodes (including high voltage electrodes and ground electrodes) in the two adjacent layer structures. Figure 1 The electrodes in each layer structure are aligned and arranged flatly with the electrodes in the adjacent lower layer structure, so that when the reactants enter the first cavity 1, the main flow direction is a straight line from top to bottom; Figure 2 The electrodes in the layer structure are arranged in an intercalated manner with the electrodes in the adjacent lower layer structure, so that when the reactants enter the first cavity 1, the main flow direction is from top to bottom and alternately in the horizontal direction. Figure 1 and Figure 2 It can be seen that under the premise that the flow rate of the reactants remains unchanged, Figure 2 A longer average residence time of reactants in the provided discharge device is achieved.

[0093] Figure 1 and Figure 2In the present invention, each electrode tube is exemplarily configured to be hollow and connected to each other in series and / or in parallel to form a second cavity.

[0094] Preferably, the gap between two adjacent layer structures is greater than 0 and less than or equal to 100 mm.

[0095] Preferably, in each of the layer structures, the gap between two adjacent electrodes is greater than 0 and less than or equal to 100 mm.

[0096] Preferably, the ratio between L2 and the length L3 of the discharge tube is independently 1:(2-1500), more preferably 1:(20-500), and even more preferably 1:(20-300).

[0097] The device of the present invention also has the following preferred features:

[0098] Preferably, the high-voltage electrodes 3 are connected in parallel with each other.

[0099] Preferably, the ground electrodes 4 are connected in parallel with each other.

[0100] Preferably, the device further includes a grounding wire 5 , one end of which is electrically connected to the grounding electrode 4 .

[0101] Preferably, the first inlet 11 is provided at an upper portion of the first cavity 1 , and the first outlet 12 is provided at a bottom portion of the first cavity 1 .

[0102] According to a preferred embodiment, at least one of the plurality of high-voltage electrodes 3 and the plurality of ground electrodes 4 is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0103] According to another preferred embodiment, each of the high-voltage electrodes 3 and each of the grounding electrodes 4 is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0104] According to another preferred embodiment, each of the high-voltage electrodes 3 is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0105] According to another preferred embodiment, each of the ground electrodes 4 is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

[0106] Preferably, the sizes of the high-voltage electrodes 3 and the grounding electrodes 4 are the same, and the high-voltage electrodes 3 and the grounding electrodes 4 are all cylindrical.

[0107] According to a preferred embodiment, the size of each high-voltage electrode 3 is exactly the same as the size of each ground electrode 4 .

[0108] Preferably, the diameters of the high-voltage electrode 3 and the ground electrode 4 are independently 0.1 to 100 mm, more preferably 0.5 to 50 mm.

[0109] Preferably, the ratio of the diameter of the high-voltage electrode 3 and the ground electrode 4 to the length of the corresponding high-voltage electrode 3 and the ground electrode 4 is independently 1:(5-600), preferably 1:(10-400).

[0110] Preferably, the second inlet 21 and the second outlet 22 are respectively provided at the lower portion and the upper portion of the second cavity 2 .

[0111] In order to more intuitively describe the arrangement of the ground electrode and the high voltage electrode in the device of the present invention, the present invention provides Figure 3 The three-dimensional structure diagram of the interior of the first cavity is used for explanation. Figure 3 The high voltage electrode 3 and the ground electrode 4 form a high voltage-ground mixed layer structure, and each high voltage-ground mixed layer structure is arranged in parallel.

[0112] The high-flux low-temperature plasma discharge equipment provided by the present invention also has the following specific advantages:

[0113] (1) The high-flux low-temperature plasma discharge device preferably uses a conductive solid material as a ground electrode. When such a ground electrode is combined with the device structure of the present invention, the micro-discharge current generated by the discharge is larger, which is more conducive to the discharge decomposition reaction of hydrogen sulfide molecules.

[0114] (2) The high-flux low-temperature plasma discharge equipment is equipped with a jacket structure, which can control the temperature of the discharge equipment by controlling the temperature of the heat-conducting medium in the jacket, so that the sulfur produced by the decomposition of hydrogen sulfide can flow out of the discharge area smoothly, avoiding sulfur solidification and clogging the discharge equipment, and making the discharge continue stably.

[0115] (3) The high-flux low-temperature plasma discharge device preferably controls the ratio between L2 and D1 to be (0.1-150):1, preferably (0.2-100):1; more preferably (0.5-80):1; further preferably (0.5-50:1), and in combination with other structures of the discharge device of the present invention, the conversion rate of hydrogen sulfide can be significantly improved and the decomposition energy consumption can be reduced.

[0116] The present invention will be described in detail below through examples. In the following examples, unless otherwise specified, all raw materials used are commercially available.

[0117] The thickness of the barrier medium in the following examples is the same.

[0118] The conversion rate of hydrogen sulfide in the following examples is calculated according to the following formula:

[0119] Conversion rate of hydrogen sulfide % = number of moles of converted hydrogen sulfide / number of moles of initial hydrogen sulfide × 100%

[0120] The energy consumption for decomposing hydrogen sulfide in the following examples was measured by an oscilloscope and calculated using Lissajous figures.

[0121] Example 1

[0122] use Figure 1 The device shown performs hydrogen sulfide decomposition reaction, and the specific structure and structural parameters of the device are as follows:

[0123] Discharge equipment includes:

[0124] a first cavity, wherein a first inlet and a first outlet are respectively provided on the first cavity;

[0125] a high-voltage electrode disposed in the first cavity; in each layer structure containing the high-voltage electrode, the number of the high-voltage electrodes is 3 or 4, the high-voltage electrodes are parallel to each other, the material forming the high-voltage electrodes is a hollow stainless steel metal tube, and the high-voltage electrodes are of the same size;

[0126] a grounding electrode disposed in the first cavity; in each layer structure containing a grounding electrode, the number of the grounding electrodes is 3 or 4, the grounding electrodes are parallel to each other, the grounding electrodes are formed of a hollow stainless steel metal tube, and the grounding electrodes have the same size;

[0127] The hollow high-voltage electrodes and the hollow ground electrodes are connected to form a second cavity, and the second cavity is respectively provided with a second inlet (disposed at the lower part of the device) and a second outlet (disposed at the upper part of the device), and the heat transfer medium is introduced through the second inlet and led out through the second outlet;

[0128] A blocking medium, which is wrapped around each high-voltage electrode and is made of hard glass;

[0129] A grounding electrode is inserted between two adjacent high-voltage electrodes in each layer structure, thereby forming a high-voltage-grounding mixed layer that alternately contains high-voltage electrodes and grounding electrodes. The number of layers of the high-voltage-grounding mixed layer is 10, and each of the high-voltage-grounding mixed layers is arranged in parallel; in each of the high-voltage-grounding mixed layers, there is a gap between adjacent high-voltage electrodes and grounding electrodes; and there is a gap between two adjacent high-voltage-grounding mixed layers.

[0130] The gap between adjacent high-voltage electrodes and ground electrodes is equal to the gap between two adjacent high-voltage-ground mixed layers, and the ratio of L2 to the thickness D1 of the blocking medium is 50:1;

[0131] The size of each high-voltage electrode is the same as that of each grounding electrode, and the ratio of diameter to length is 1:220;

[0132] The ratio between L2 and the length of the discharge tube L3 is 1:300;

[0133] The volume of the first cavity of the low-temperature, high-flux plasma discharge device of this embodiment is 3L.

[0134] The operation steps of the flux plasma discharge equipment:

[0135] Nitrogen gas was introduced into the first cavity of the discharge device from the first inlet to purge air from the discharge region, and the gas was discharged from the first outlet. Simultaneously, a heat transfer medium (specifically dimethyl silicone oil) was introduced into the second cavity from the second inlet and discharged from the second outlet. The temperature of the heat transfer medium was maintained at 305°C.

[0136] Then, an H2S / Ar gas mixture is introduced into the first cavity of the discharge device from the first inlet, where the H2S volume fraction is 6%. The reactant flow rate is controlled so that the average residence time of the gas in the discharge zone is 15.1s and the gas pressure is 0.1MPa. After the H2S / Ar gas mixture has been introduced into the discharge device for 30 minutes, an AC high-voltage power supply is connected, and a plasma discharge field is formed between the high-voltage electrode and the ground electrode by adjusting the voltage and frequency. The discharge conditions are as follows: voltage of 21.7kV, frequency of 10.1kHz, and current of 3.7A. The hydrogen sulfide gas is ionized in the discharge region and decomposed into hydrogen and elemental sulfur. The elemental sulfur produced by the discharge slowly flows down the wall of the first cavity and flows out from the first outlet, and the reacted gas is also drawn out from the first outlet.

[0137] Results: After 20 minutes of continuous hydrogen sulfide decomposition, the measured H2S conversion rate was 71.9%. No abnormalities were observed after 100 hours of continuous discharge, and both the discharge state and H2S conversion rate remained stable. Furthermore, the decomposition energy consumption of this embodiment was 17.8 eV / H2S molecule (17.8 eV of energy was required to decompose one H2S molecule).

[0138] Example 2

[0139] This embodiment adopts Figure 2 The device shown performs hydrogen sulfide decomposition reaction, and the specific structure and structural parameters of the device are as follows:

[0140] Discharge equipment includes:

[0141] a first cavity, wherein a first inlet and a first outlet are respectively provided on the first cavity;

[0142] a high-voltage electrode disposed in the first cavity; in each layer structure containing the high-voltage electrode, the number of the high-voltage electrodes is 3 or 4, the high-voltage electrodes are parallel to each other, the material forming the high-voltage electrodes is a hollow graphite tube, and the dimensions of the high-voltage electrodes are the same;

[0143] A grounding electrode, the grounding electrode being disposed in the first cavity; in each layer structure containing the grounding electrode, the number of the grounding electrodes is 3 or 4, the grounding electrodes are parallel to each other, the material forming the grounding electrodes is a hollow graphite tube, and the grounding electrodes have the same size;

[0144] A blocking medium, wherein the blocking medium is wrapped around each ground electrode and is formed of polytetrafluoroethylene;

[0145] The hollow high-voltage electrodes and the hollow ground electrodes are connected to form a second cavity, and the second cavity is provided with a second inlet (disposed at the lower part of the device) and a second outlet (disposed at the upper part of the device), respectively, and the heat transfer medium is introduced through the second inlet and led out through the second outlet;

[0146] The high-voltage electrodes in each layer structure containing high-voltage electrodes and the grounding electrodes in each layer structure containing grounding electrodes are alternately arranged, so that a grounding electrode is inserted between two adjacent high-voltage electrodes in each layer structure containing high-voltage electrodes, thereby forming a high-voltage-grounding mixed layer that alternately contains high-voltage electrodes and grounding electrodes. The number of layers of the high-voltage-grounding mixed layer is 10, and each of the high-voltage-grounding mixed layers is arranged in parallel; in each of the high-voltage-grounding mixed layers, there is a gap between adjacent high-voltage electrodes and grounding electrodes; and there is a gap between two adjacent high-voltage-grounding mixed layers.

[0147] The gap between adjacent high-voltage electrodes and ground electrodes is equal to the gap between two adjacent high-voltage-ground mixed layers, and the ratio of L2 to the thickness D1 of the blocking medium is 2:1;

[0148] The size of each high-voltage electrode is the same as that of each grounding electrode, and the ratio of diameter to length is 1:355;

[0149] The ratio between L2 and the length of the discharge tube L3 is 1:350;

[0150] The volume of the first cavity of the device of this embodiment is 3L.

[0151] Device operation steps:

[0152] Nitrogen gas was introduced into the first cavity of the discharge device from the first inlet to purge air from the discharge region, and the gas was discharged from the first outlet. Simultaneously, a heat transfer medium (specifically dimethyl silicone oil) was introduced into the second cavity from the second inlet and discharged from the second outlet. The temperature of the heat transfer medium was maintained at 137°C.

[0153] Then, an H2S / Ar gas mixture is introduced into the first cavity of the discharge device from the first inlet, where the H2S volume fraction is 60%. The reactant flow rate is controlled so that the average residence time of the gas in the discharge zone is 19.1s and the gas pressure is 0.27MPa. After the H2S / Ar gas mixture has been introduced into the discharge device for 30 minutes, an AC high-voltage power supply is connected, and a plasma discharge field is formed between the high-voltage electrode and the ground electrode by adjusting the voltage and frequency. The discharge conditions are as follows: voltage of 21.4kV, frequency of 1.5kHz, and current of 3.5A. The hydrogen sulfide gas is ionized in the discharge region and decomposed into hydrogen and elemental sulfur. The elemental sulfur produced by the discharge slowly flows down the wall of the first cavity and flows out from the first outlet, and the post-reaction gas is drawn out from the first outlet.

[0154] Results: After 20 minutes of continuous hydrogen sulfide decomposition, the measured H2S conversion rate was 72.3%. No abnormalities were observed after 100 hours of continuous discharge, and both the discharge state and H2S conversion rate remained stable. The decomposition energy consumption for this example was 18.1 eV / H2S molecule.

[0155] Example 3

[0156] This embodiment uses a discharge device similar to that of Embodiment 1, except that the barrier dielectric in the discharge device of this embodiment is arranged on the outer surfaces of the high-voltage electrode and the ground electrode, that is, a double-dielectric barrier discharge.

[0157] The gap between two adjacent high-voltage-ground mixed layers is 1.2 times the gap between adjacent high-voltage electrodes and ground electrodes, and the ratio of L2 to the thickness D1 of the blocking medium is 15:1;

[0158] The size of each high-voltage electrode is the same as that of each grounding electrode, and the ratio of diameter to length is 1:100;

[0159] The ratio between L2 and the length of the discharge tube L3 is 1:50;

[0160] The volume of the first cavity of the device of this embodiment is 3.2L.

[0161] An H2S / H2 gas mixture is introduced into the first cavity of the discharge device from the first inlet, where the H2S volume fraction is 10%. The reactant flow rate is controlled so that the average residence time of the gas in the discharge zone is 24.5 seconds and the gas pressure is 0.05 MPa. After the H2S / H2 gas mixture has been introduced into the discharge device for 30 minutes, an AC high-voltage power supply is connected, and a plasma discharge field is formed between the high-voltage electrode and the ground electrode by adjusting the voltage and frequency. The discharge conditions are: voltage of 16.5 kV, frequency of 3.5 kHz, and current of 3.1 A. Hydrogen sulfide gas is ionized in the discharge region, decomposing into hydrogen and elemental sulfur. The elemental sulfur produced by the discharge slowly flows down the wall of the first cavity and out of the first outlet, and the post-reaction gas is drawn out from the first outlet.

[0162] The rest are the same as in Example 1.

[0163] Results: After 20 minutes of continuous hydrogen sulfide decomposition, the measured H2S conversion rate was 71.7%. No abnormalities were observed after 100 hours of continuous discharge, and both the discharge state and H2S conversion rate remained stable. The decomposition energy consumption for this example was 16.8 eV / H2S molecule.

[0164] Example 4

[0165] This embodiment uses a device similar to that of Example 1 to carry out the decomposition reaction of hydrogen sulfide, except that:

[0166] The gap between adjacent high-voltage electrodes and ground electrodes is equal to the gap between two adjacent high-voltage-ground mixed layers, and the ratio of L2 to the thickness D1 of the blocking medium is 92:1;

[0167] The rest are the same as in Example 1.

[0168] In addition, this embodiment adopts the same operating method as that of Example 1 to carry out the hydrogen sulfide decomposition reaction.

[0169] Results: After 20 minutes of continuous hydrogen sulfide decomposition, the measured H2S conversion rate was 63.7%. No abnormalities were observed after 100 hours of continuous discharge, and both the discharge state and H2S conversion rate remained stable. The decomposition energy consumption for this example was 21.7 eV / H2S molecule.

[0170] Example 5

[0171] This embodiment uses a device similar to that of Example 1 to carry out the decomposition reaction of hydrogen sulfide, except that:

[0172] The gap between adjacent high-voltage electrodes and ground electrodes is equal to the gap between two adjacent high-voltage-ground mixed layers, and the ratio of L2 to the thickness D1 of the blocking medium is 125:1;

[0173] The rest are the same as in Example 1.

[0174] In addition, this embodiment adopts the same operating method as that of Example 1 to carry out the hydrogen sulfide decomposition reaction.

[0175] Results: After 20 minutes of continuous hydrogen sulfide decomposition, the measured H2S conversion rate was 62.1%. No abnormalities were observed after 100 hours of continuous discharge, and both the discharge state and H2S conversion rate remained stable. The decomposition energy consumption for this example was 28.5 eV / H2S molecule.

[0176] Example 6

[0177] This embodiment uses a device similar to that of Example 3 to carry out the decomposition reaction of hydrogen sulfide, except that:

[0178] The ratio between L2 and the length of the discharge tube L3 is 1:700;

[0179] The rest are the same as in Example 3.

[0180] This embodiment also uses the same operating method as that of Example 3 to carry out the hydrogen sulfide decomposition reaction.

[0181] Results: After 20 minutes of continuous hydrogen sulfide decomposition, the measured H2S conversion rate was 64.2%. No abnormalities were observed after 100 hours of continuous discharge, and both the discharge state and H2S conversion rate remained stable. The decomposition energy consumption for this example was 27.6 eV / H2S molecule.

[0182] It can be seen from the above results that the discharge equipment provided by the present invention can achieve a high hydrogen sulfide conversion rate, and the hydrogen sulfide conversion rate can be stably maintained at a high level.

[0183] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for decomposing hydrogen sulfide, the method being implemented in a high-flux low-temperature plasma discharge device, the discharge device comprising: A first cavity (1), wherein the first cavity (1) is provided with a first inlet (11) and a first outlet (12); a second cavity (2), wherein the second cavity (2) is nested inside the first cavity (1), and a second inlet (21) and a second outlet (22) are respectively provided on the second cavity (2); A high-voltage electrode (3) and a grounding electrode (4), wherein the material forming the grounding electrode (4) is a solid conductive material, the high-voltage electrode (3) and the grounding electrode (4) are arranged in the first cavity (1), the high-voltage electrode (3) and the grounding electrode (4) are each a plurality to form a layer structure with a number ≥ 1, and in each layer structure, the high-voltage electrode (3) and the grounding electrode (4) are arranged at intervals; the gap between two adjacent layer structures is greater than 0 and less than or equal to 100 mm; in each layer structure, the gap between two adjacent electrodes is greater than 0 and less than or equal to 100 mm; a blocking medium, the blocking medium being arranged on the outer surface of the high-voltage electrode (3) and / or the grounding electrode (4); The distance between the high-voltage electrode (3) and the ground electrode (4) is L1, the thickness of the blocking medium is D1, L2=L1-D1, and the ratio between L2 and D1 is (0.5-50):1; The ratio between L2 and the length L3 of the discharge tube is independently 1:(20-300); The method comprises: grounding a ground electrode (4) of the high-flux low-temperature plasma discharge device, connecting a high-voltage electrode (3) to a power source, performing dielectric barrier discharge, introducing a raw gas containing hydrogen sulfide from a reactor inlet into a first cavity (1) of the high-flux low-temperature plasma discharge device to perform a decomposition reaction of the hydrogen sulfide, and leading a stream obtained after the decomposition out from a first outlet, and maintaining a required temperature of the high-flux low-temperature plasma discharge device by continuously introducing a heat-conducting medium into a second cavity of the high-flux low-temperature plasma discharge device from a second inlet and leading the heat-conducting medium out from a second outlet; The conditions of the dielectric barrier discharge include: a discharge voltage of 5 kV to 15 kV and a discharge frequency of 500 to 13000 Hz; The conditions of the decomposition reaction include: a reaction temperature of 119-444.6°C and a reaction pressure of 0-0.6 MPa; The residence time of the raw gas containing hydrogen sulfide in the discharge region of the high flux low temperature plasma discharge device is 2×10 -5 ~60s.

2. The method according to claim 1, wherein The conditions of the decomposition reaction include: a reaction pressure of 0-0.3 MPa.

3. The method according to claim 1 or 2, wherein The hydrogen sulfide decomposition reaction is carried out in the presence of a carrier gas, and the carrier gas is selected from at least one of nitrogen, hydrogen, helium, argon, water vapor, carbon monoxide, carbon dioxide, methane, ethane and propane.

4. The method according to claim 1 or 2, wherein: The hydrogen sulfide decomposition reaction is carried out in the presence of a carrier gas, and the carrier gas is selected from at least one of hydrogen, argon, helium and nitrogen.

5. The method according to claim 1, wherein In two adjacent layer structures, the center of the electrode in the upper layer structure is aligned with or offset from the center of the electrode in the lower layer structure.

6. The method according to claim 1 or 2, wherein: The high-voltage electrodes (3) are connected in parallel with each other.

7. The method according to claim 1 or 2, wherein: The ground electrodes (4) are connected in parallel to each other.

8. The method according to claim 1 or 2, wherein: The material of the blocking medium is an electrically insulating material.

9. The method according to claim 1 or 2, wherein: The material of the blocking medium is selected from at least one of glass, quartz, ceramic, enamel, polytetrafluoroethylene and mica.

10. The method according to claim 1 or 2, wherein: The ground electrode (4) and the high-voltage electrode (3) are made of conductive materials.

11. The method according to claim 1 or 2, wherein: The materials of the ground electrode (4) and the high-voltage electrode (3) are independently selected from at least one of graphite tubes, graphite powder, metal tubes, metal rods, metal powder, alloy tubes, alloy rods, alloy powder and graphite rods.

12. The method according to claim 1 or 2, wherein: The device further comprises a grounding wire (5), one end of which is electrically connected to the grounding electrode (4).

13. The method according to claim 1 or 2, wherein: The first inlet (11) is provided at the upper portion of the first cavity (1), and the first outlet (12) is provided at the bottom portion of the first cavity (1).

14. The method according to claim 1 or 2, wherein: At least one of the plurality of high-voltage electrodes (3) and the plurality of ground electrodes (4) is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

15. The method according to claim 1 or 2, wherein: Each of the high-voltage electrodes (3) and each of the grounding electrodes (4) is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

16. The method according to claim 1 or 2, wherein: Each of the high-voltage electrodes (3) is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

17. The method according to claim 1 or 2, wherein: Each of the grounding electrodes (4) is a hollow structure, and the hollow structures are connected to each other to form the second cavity.

18. The method according to claim 1 or 2, wherein: The sizes of the high-voltage electrodes (3) and the grounding electrodes (4) are the same, and the high-voltage electrodes (3) and the grounding electrodes (4) are all cylindrical.

19. The method according to claim 1 or 2, wherein: The diameters of the high-voltage electrode (3) and the ground electrode (4) are independently 0.1 to 100 mm.

20. The method according to claim 1 or 2, wherein: The diameters of the high-voltage electrode (3) and the ground electrode (4) are independently 0.5 to 50 mm.

21. The method according to claim 18, wherein The height-to-diameter ratios of the high-voltage electrode (3) and the ground electrode (4) are independently (5-600):

1.

22. The method according to claim 18, wherein The height-to-diameter ratios of the high-voltage electrode (3) and the ground electrode (4) are independently (10-400):

1.

23. The method according to claim 1 or 2, wherein The second inlet (21) and the second outlet (22) are respectively arranged at the lower part and the upper part of the second cavity (2).

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