Honeycomb ceramic type plasma SF6 degradation device and degradation method

Abstract

The invention relates to the technical field of sulfur hexafluoride degradation, and discloses a honeycomb ceramic type SF6 plasma degradation device which comprises a DBD reactor, a gas supply unit is arranged on the left side of the DBD reactor, a power supply unit is arranged at the bottom of the DBD reactor, a processing unit is arranged on the right side of the DBD reactor, and the DBD reactor is connected with the gas supply unit through a gas pipe. The DBD reactor is electrically connected with the power supply unit; according to the device, a traditional single-tube structure type inner electrode is broken through, a novel detachable honeycomb ceramic structure is adopted as the inner electrode of the reactor, the porous structure provides a good channel for flowing and distribution of gas, the porous channel is beneficial to adsorption of a catalyst and decomposition products, and the degradation process can be effectively promoted; meanwhile, the honeycomb ceramic is used as an inner electrode and is detachable, and an inner electrode tube is inserted into a slightly large hole in the middle of the honeycomb ceramic, so that the device is convenient to mount, clean and maintain, and the operation cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sulfur hexafluoride degradation, and in particular to a device and a method for degrading SF6 using honeycomb ceramic plasma. Background Art

[0002] SF6 has excellent insulation and arc extinguishing properties and is widely used in electrical equipment such as gas-insulated circuit breakers, transmission pipelines, insulated substations and transformers. SF6 is listed as one of the six greenhouse gases with restricted emissions due to its high global warming potential (GWP). It is very stable in the atmosphere, has a long life cycle and is difficult to degrade naturally. With the rapid development of the power industry, the use of SF6 has increased year by year, but SF6 leakage occurs in the power system every year due to equipment maintenance and replacement, and the direct discharge of SF6 waste gas will have a serious impact on the environment. At present, the main emission reduction measures are to replace SF6 gas with environmentally friendly gases (low GWP gases), SF6 recycling and recycling, and SF6 waste gas degradation treatment technology. Among them, SF6 degradation treatment technology has the advantages of high-efficiency degradation and low energy consumption. SF6 degradation treatment methods are divided into pyrolysis, photocatalysis and plasma methods. The plasma method uses high-energy electrons, ions and free radicals in the plasma to react with effective active substances such as SF6 molecules, which can dissociate them in a short time. Among them, the dielectric barrier discharge (DBD) plasma method has the advantages of high degradation rate, high energy efficiency, reliable discharge and simple device, and is widely used in treating waste gas.

[0003] In the prior art, DBD plasma technology is used to perform degradation experiments on SF6, and the effects of different input voltages, background gases, and different catalyst types and sizes on the degradation effect of SF6 are analyzed. In the experiment, when glass beads are used as catalysts, the degradation efficiency is not high, and the content of SO2F2 in the degradation products is high, and the content of SO2 is low; when γ-Al2O3 is used as a catalyst, the content of SO2 in the product is high, and the formation of substances such as SO2F2 and SOF2 is inhibited. The above results show that different types of filling materials will affect the distribution of the content of degradation products, and metal oxides such as γ-Al2O3 can improve the distribution of the content of degradation products. At present, when the coaxial DBD plasma is used to degrade SF6, the inner electrode always adopts a single-tube structure, and the filling material needs to fill the entire DBD reactor, which will affect the economic cost. Due to the many factors that affect the SF6 rate, different inner electrode structures will also affect the SF6 degradation rate, but such issues have not been discussed, so they are worth studying. At the same time, the internal electrode structure in the current DBD plasma technology for degrading SF6 is too single, and different internal electrode structures will also affect the SF6 degradation rate. At the same time, in order to change the filling form of the catalyst and reduce the operating cost, the catalyst adsorption method can be used to solve this problem. Therefore, a honeycomb ceramic plasma SF6 degradation device and degradation method are proposed to solve the above problems. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a device and a method for degrading SF6 using honeycomb ceramic plasma, which has the advantages of significantly improving the degradation rate of SF6 and being green and environmentally friendly, and solves the problems mentioned in the above background technology.

[0005] In order to achieve the above-mentioned purpose of significantly improving the degradation rate of SF6 and being green and environmentally friendly, the present invention provides the following technical solutions: a honeycomb ceramic plasma degradation SF6 device, comprising a DBD reactor, a gas supply unit is arranged on the left side of the DBD reactor, a power supply unit is arranged at the bottom of the DBD reactor, and a processing unit is arranged on the right side of the DBD reactor; The DBD reactor is connected to the gas supply unit via an air pipe, the DBD reactor is electrically connected to the power supply unit, and the DBD reactor is connected to the processing unit via an air pipe; The DBD reactor comprises an outer electrode, a detachable honeycomb ceramic inner electrode is clamped inside the outer electrode, the detachable honeycomb ceramic inner electrode is composed of a honeycomb ceramic and an inner electrode tube, an inner electrode tube hole is provided inside the honeycomb ceramic, a catalyst hole is provided inside the honeycomb ceramic, the inner electrode tube is clamped inside the inner electrode tube hole, and the inner electrode tube hole size is larger than the catalyst hole size; The outer surface of the outer electrode is provided with a sealing connector, and the sealing connector is used to seal the air supply unit and the air pipe of the processing unit.

[0006] Preferably, the gas supply unit includes a gas distributor, the gas inlet of the gas distributor is connected to an SF6 gas supply bottle and an Ar gas supply bottle through a gas pipe, the outer surfaces of the gas pipes connecting the SF6 gas supply bottle, the Ar gas supply bottle and the gas distributor are all provided with pressure reducing valves, and the outer surface of the gas pipe connecting the gas distributor and the DBD reactor is provided with an electromagnetic flowmeter and a solenoid valve.

[0007] Preferably, the power supply unit comprises a plasma power supply, one side of the plasma power supply is electrically connected to a voltage regulator, and the other side of the plasma power supply is fixedly connected to an oscilloscope.

[0008] Preferably, the alkali solution treatment unit comprises an alkali solution treatment tank, the top of which is fixedly connected with an air outlet pipe, the alkali solution treatment tank is filled with alkali solution, and the right air pipe of the DBD reactor is inserted into the alkali solution.

[0009] Preferably, the number of the inner electrode tube hole is one, the diameter of the inner electrode tube hole is 0.6 cm, the number of the catalyst holes is eight, the diameters of the eight catalyst holes are all 0.4 cm, the eight catalyst holes are evenly distributed in a ring shape on the outer surface of the inner electrode tube hole, and the length of the inner electrode tube is 35 cm.

[0010] Preferably, the method for degrading SF6 by honeycomb ceramic plasma comprises the following specific steps: S1: Clamp the inner electrode tube into the tube hole of the inner electrode tube so that the honeycomb ceramic is located in the middle of the inner electrode tube; S2: Prepare Cu(NO3)2 powder, add water to the Cu(NO3)2 powder, and stir it evenly without precipitation to obtain a Cu(NO3)2 aqueous solution; S3: The detachable honeycomb ceramic inner electrode is completely immersed in a Cu(NO3)2 aqueous solution, evaporated in a water bath, and calcined at high temperature to decompose into a CuO catalyst, which is evenly attached to the catalyst pores; S4: The outer electrode is sleeved on the outer surface of the detachable honeycomb ceramic inner electrode, and the two ends of the outer electrode are connected to the gas distribution device and the alkali solution treatment tank by using flanges, and the outer electrode is connected to the plasma power supply by using a high-voltage wire; S5: SF6 gas supply cylinder and Ar gas supply cylinder are connected to the gas distributor through gas pipes, and the voltage regulator and oscilloscope are connected to the plasma power supply through wires; S6: Open the pressure reducing valves at the gas pipes of the SF6 gas supply bottle and the Ar gas supply bottle, control the input opening of SF6 and Ar through the pressure reducing valve, mix them inside the gas distributor according to the ratio of SF6 and Ar set by the gas distributor, and form a uniform mixed gas; S7: Control the flow rate of the mixed gas by combining an electromagnetic flow meter and an electromagnetic valve to deliver the mixed gas to the DBD reaction; S8: Start the plasma power supply. Under the action of the high-voltage electric field, the mixed gas in the catalyst hole is broken down to generate plasma. Active substances such as high-energy electrons, ions and free radicals in the plasma collide and react with SF6 molecules. The CuO catalyst synergistically plays a catalytic role in the plasma environment to promote the degradation process of SF6 gas. S9: After degradation, first close the pressure reducing valve at the SF6 gas supply bottle to keep the DBD reactor running stably. After 10 minutes, turn off the plasma power supply and continue to introduce Ar to discharge the gas in the DBD reactor into the alkali solution in the alkali solution treatment pool, treat the tail gas, and discharge it through the outlet pipe; S10: Finally, close the pressure reducing valve at the Ar gas supply bottle.

[0011] Compared with the prior art, the present invention provides a device and method for SF6 degradation by honeycomb ceramic plasma, which has the following beneficial effects: 1. The honeycomb ceramic plasma degradation SF6 device breaks the traditional single-tube structure of the inner electrode and adopts a novel detachable honeycomb ceramic structure as the inner electrode of the reactor. Its porous structure provides a good channel for the flow and distribution of gas. The porous channel is conducive to the adsorption of catalysts and decomposition products, which can effectively promote the degradation process. At the same time, the honeycomb ceramic is used as the inner electrode with a detachable design. The inner electrode tube is inserted into the slightly larger hole in the middle of the honeycomb ceramic, which is convenient for the installation, cleaning and maintenance of the device and reduces the operating cost.

[0012] 2. The degradation method of SF6 by honeycomb ceramic plasma uses Cu(NO3)2 powder as a precursor, which is converted into CuO catalyst after being evaporated in a water bath and calcined at high temperature and attached to the porous channels of honeycomb ceramics. The CuO catalyst and plasma jointly promote the dissociation of SF6. At the same time, the catalyst surface can also be used as a place for the active substance to react with SF6 molecules, which can accelerate the degradation reaction. Due to the presence of CuO catalyst, the degradation product tends to produce SO2, and the generation of harmful gases such as SO2F2 is effectively inhibited. The tail gas is treated in an alkali liquid treatment pool. The alkali liquid can absorb and neutralize most of the acidic gases, which can effectively prevent the acidic gases after the reaction from causing harm to the human body and the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the structure of a honeycomb ceramic plasma SF6 degradation device proposed by the present invention; Figure 2 A schematic diagram of a gas supply unit of a honeycomb ceramic plasma SF6 degradation device proposed in the present invention; Figure 3 This is a schematic diagram of a DBD reactor for a honeycomb ceramic plasma degradation of SF6 proposed by the present invention; Figure 4 This is a schematic diagram of a processing unit of a honeycomb ceramic plasma SF6 degradation device proposed by the present invention; Figure 5 A schematic diagram of a power supply unit of a honeycomb ceramic plasma SF6 degradation device proposed by the present invention; Figure 6 This is a detailed structural schematic diagram of a DBD reactor of a honeycomb ceramic plasma degradation device for SF6 proposed by the present invention; Figure 7 This is a schematic diagram of a honeycomb ceramic plasma degradation device for SF6 proposed by the present invention.

[0014] In the figure: 1 DBD reactor, 101 outer electrode, 102 detachable honeycomb ceramic inner electrode, 1021 inner electrode tube hole, 1022 catalyst hole, 1023 honeycomb ceramic, 1024 inner electrode tube, 103 sealing connector, 2 gas supply unit, 201 gas distributor, 202 SF6 gas supply bottle, 203 Ar gas supply bottle, 204 pressure reducing valve, 205 electromagnetic flowmeter, 206 solenoid valve, 3 power supply unit, 301 plasma power supply, 302 voltage regulator, 303 oscilloscope, 4 processing unit, 401 alkali solution treatment tank, 402 gas outlet pipe. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] Example 1: Please refer to Figure 1-7 A honeycomb ceramic plasma SF6 degradation device includes a DBD reactor 1, a gas supply unit 2 is arranged on the left side of the DBD reactor 1, a power supply unit 3 is arranged at the bottom of the DBD reactor 1, and a processing unit 4 is arranged on the right side of the DBD reactor 1.

[0017] The DBD reactor 1 is connected to the gas supply unit 2 through an air pipe, the DBD reactor 1 is electrically connected to the power supply unit 3, and the DBD reactor 1 is connected to the processing unit 4 through an air pipe. The DBD reactor 1 includes an outer electrode 101, and a detachable honeycomb ceramic inner electrode 102 is clamped inside the outer electrode 101. The detachable honeycomb ceramic inner electrode 102 is composed of a honeycomb ceramic 1023 and an inner electrode tube 1024. An inner electrode tube hole 1021 is provided inside the honeycomb ceramic 1023, and a catalyst hole 1022 is provided inside the honeycomb ceramic 1023. The inner electrode tube 1024 is clamped inside the inner electrode tube hole 1021, and the size of the inner electrode tube hole 1021 is larger than the size of the catalyst hole 1022. The structure of the honeycomb ceramic 1023 has a large specific surface area and porosity, which is conducive to uniform distribution and flow of gas. At the same time, the porous structure can be used as a carrier of the catalyst. This structural design can effectively improve the SF6 degradation efficiency. In addition, the main component of honeycomb ceramics is Al2O3, which can provide more active sites for the catalyst and accelerate the degradation reaction. Because the CuO catalyst has excellent catalytic activity, it can catalyze the decomposition of SF6 molecules, reduce the activation energy of the reaction, accelerate the degradation reaction, and the degradation products tend to produce SO2 and other substances that are easy to handle.

[0018] In addition, a sealing connector 103 is provided on the outer surface of the outer electrode 101, and the sealing connector 103 is used to seal the gas supply unit 2 and the gas pipe of the processing unit 4. The number of the inner electrode tube hole 1021 is one, and the diameter of the inner electrode tube hole 1021 is 0.6 cm. The number of the catalyst holes 1022 is eight, and the diameter of the eight catalyst holes 1022 is 0.4 cm. The eight catalyst holes 1022 are evenly distributed on the outer surface of the inner electrode tube hole 1021 in a ring shape, and the length of the inner electrode tube 1024 is 35 cm.

[0019] Secondly, the gas supply unit 2 includes a gas distributor 201, the gas inlet of the gas distributor 201 is connected to the SF6 gas supply bottle 202 and the Ar gas supply bottle 203 through a gas pipe, the outer surface of the gas pipe connecting the SF6 gas supply bottle 202, the Ar gas supply bottle 203 and the gas distributor 201 is provided with a pressure reducing valve 204, and the outer surface of the gas pipe connecting the gas distributor 201 and the DBD reactor 1 is provided with an electromagnetic flowmeter 205 and a solenoid valve 206.

[0020] Furthermore, the power supply unit 3 includes a plasma power supply 301 , one side of the plasma power supply 301 is electrically connected to a voltage regulator 302 , and the other side of the plasma power supply 301 is fixedly connected to an oscilloscope 303 .

[0021] In addition, the alkali solution treatment unit 4 includes an alkali solution treatment tank 401, the top of which is fixedly connected with an air outlet pipe 402, the alkali solution treatment tank 401 is filled with alkali solution, and the right air pipe of the DBD reactor 1 is inserted into the alkali solution.

[0022] The honeycomb ceramic plasma degradation method for SF6 comprises the following specific steps: S1: clamp the inner electrode tube 1024 into the inner electrode tube hole 1021 so that the honeycomb ceramic 1023 is located in the middle of the inner electrode tube 1024; S2: Prepare 5.64 g of Cu(NO3)2 powder, add 150 ml of water to the Cu(NO3)2 powder, and stir it evenly without precipitation to obtain a Cu(NO3)2 aqueous solution; S3: The detachable honeycomb ceramic inner electrode 102 is completely immersed in a Cu(NO3)2 aqueous solution, evaporated in a 100°C water bath, and then placed in a 150°C oven for 8 hours to completely evaporate its water. Finally, it is placed in a tube furnace for high temperature calcination at 500°C for 4 hours, so that the CuO catalyst will be uniformly attached to the catalyst pores 1022; CuO will be uniformly attached to the porous channels of the honeycomb ceramic 1023. Through the synergistic effect of DBD plasma technology and catalysts, the efficient degradation of SF6 waste gas can be achieved, and the degradation products tend to generate SO2 that is easy to handle. After being treated with alkaline solution, they can be directly discharged, which can reduce pollution to the environment. It is an efficient and environmentally friendly waste gas treatment technology. The presence of CuO can significantly improve the degradation rate of SF6 and has a certain product selectivity, so that the SF6 degradation products are more inclined to generate SO2 and other easy-to-handle substances, and effectively inhibit the generation of other difficult-to-handle products such as SOF2, SO2F2 and SOF4.

[0023] S4: The outer electrode 101 is sleeved on the outer surface of the detachable honeycomb ceramic inner electrode 102, and the two ends of the outer electrode 101 are connected to the gas distribution device 201 and the alkali solution treatment tank 401 using the flange 104, and the outer electrode 101 is connected to the plasma power supply 301 using a high-voltage wire; S5: SF6 gas supply bottle 202 and Ar gas supply bottle 203 are connected to gas distributor 201 through gas pipes, and voltage regulator 302 and oscilloscope 303 are connected to plasma power supply 301 through wires; S6: Open the pressure reducing valve 204 at the gas pipes of the SF6 gas supply bottle 202 and the Ar gas supply bottle 203, and control the input opening of SF6 and Ar through the pressure reducing valve 204. According to the SF6 and Ar ratio set by the gas distributor 201, the ratio is 2% SF6 and 98% Ar, and fully mix them inside the gas distributor to form a uniform mixed gas; S7: The mixed gas flow rate is controlled by the electromagnetic flowmeter 205 and the electromagnetic valve 206 at a flow rate of 300 ml / min, and the mixed gas is delivered to the DBD reactor 1; S8: Start the plasma power supply 301, the discharge gap is 3mm, under the action of the high voltage electric field, the mixed gas in the catalyst hole 1022 is broken down to generate plasma, and the active substances such as high-energy electrons, ions and free radicals in the plasma collide and react with SF6 molecules. The CuO catalyst synergistically plays a catalytic role in the plasma environment to promote the degradation process of SF6 gas; S9: After degradation, first close the pressure reducing valve 204 at the SF6 gas supply bottle 202 to keep the DBD reactor 1 running stably. After 10 minutes, turn off the plasma power supply 301 and continue to introduce Ar to discharge the gas in the DBD reactor 1 into the alkali solution in the alkali solution treatment tank 401, treat the tail gas, and discharge it through the outlet pipe 402; the tail gas is treated in the alkali solution treatment tank 401 and then discharged into the atmosphere, which can effectively avoid the impact on human body and environment.

[0024] S10: Finally, close the pressure reducing valve 204 at the Ar gas supply bottle 203.

[0025] Table 1 Experimental data of the ratio of Cu(NO3)2 powder mass to aqueous solution volume of 5.64g:150ml

[0026] In summary, the honeycomb ceramic plasma degradation device for SF6 proposes a detachable honeycomb ceramic inner electrode structure, whose porous channels are conducive to uniform gas distribution and catalyst adsorption. CuO is evenly attached to the porous channels of the honeycomb ceramic inner electrode by water bath evaporation and other methods. The CuO catalyst can reduce the activation energy required for SF6 dissociation and accelerate the degradation reaction. The degradation rate of SF6 can be significantly improved through the catalytic effect of CuO and the enhancement effect of DBD plasma. At the same time, the presence of CuO catalyst can reduce the generation of harmful products in the degradation products, and can effectively improve the content distribution of degradation products. In addition, the device does not produce secondary pollution in the process of SF6 degradation, which meets environmental protection requirements.

[0027] Moreover, the tail gas is discharged into the atmosphere after being treated in the alkaline solution treatment tank 401, which can effectively avoid the impact on human body and environment. This technical solution breaks the traditional single inner electrode structure and catalyst attachment method, uses honeycomb ceramic as the inner electrode material, and its porous channels can be used as the attachment point of CuO catalyst, and realizes the efficient degradation of SF6 under the synergistic effect of plasma and catalyst. At the same time, the product SO2 obtained by the degradation of CuO catalyst has a large content, which is easy to handle and will not cause harm to human body and environment through absorption by alkaline solution.

[0028] Example 2: Please refer to Figure 1-7A honeycomb ceramic plasma SF6 degradation device includes a DBD reactor 1, a gas supply unit 2 is arranged on the left side of the DBD reactor 1, a power supply unit 3 is arranged at the bottom of the DBD reactor 1, and a processing unit 4 is arranged on the right side of the DBD reactor 1.

[0029] Among them, the DBD reactor 1 is connected to the gas supply unit 2 through an air pipe, the DBD reactor 1 is electrically connected to the power supply unit 3, and the DBD reactor 1 is connected to the processing unit 4 through an air pipe. The DBD reactor 1 includes an outer electrode 101, and a detachable honeycomb ceramic inner electrode 102 is clamped inside the outer electrode 101. The detachable honeycomb ceramic inner electrode 102 is composed of a honeycomb ceramic 1023 and an inner electrode tube 1024. An inner electrode tube hole 1021 is opened inside the honeycomb ceramic 1023, and a catalyst hole 1022 is opened inside the honeycomb ceramic 1023. The inner electrode tube 1024 is clamped inside the inner electrode tube hole 1021, and the size of the inner electrode tube hole 1021 is larger than the size of the catalyst hole 1022. The structure of honeycomb ceramic 1023 has a large specific surface area and porosity, which is conducive to uniform distribution and flow of gas. At the same time, the porous structure can be used as a carrier of the catalyst. This structural design can effectively improve the SF6 degradation efficiency. The main component of honeycomb ceramic is Al2O3, which can provide more active sites for the catalyst and accelerate the degradation reaction. Because the CuO catalyst has excellent catalytic activity, it can catalyze the decomposition of SF6 molecules, reduce the reaction activation energy, accelerate the degradation reaction, and the degradation products tend to generate SO2 and other substances that are easy to handle.

[0030] In addition, a sealing connector 103 is provided on the outer surface of the outer electrode 101, and the sealing connector 103 is used to seal the gas supply unit 2 and the gas pipe of the processing unit 4. The number of the inner electrode tube hole 1021 is one, and the diameter of the inner electrode tube hole 1021 is 0.6 cm. The number of the catalyst holes 1022 is eight, and the diameter of the eight catalyst holes 1022 is 0.4 cm. The eight catalyst holes 1022 are evenly distributed on the outer surface of the inner electrode tube hole 1021 in a ring shape, and the length of the inner electrode tube 1024 is 35 cm.

[0031] Secondly, the gas supply unit 2 includes a gas distributor 201, the gas inlet of the gas distributor 201 is connected to the SF6 gas supply bottle 202 and the Ar gas supply bottle 203 through a gas pipe, the outer surface of the gas pipe connecting the SF6 gas supply bottle 202, the Ar gas supply bottle 203 and the gas distributor 201 is provided with a pressure reducing valve 204, and the outer surface of the gas pipe connecting the gas distributor 201 and the DBD reactor 1 is provided with an electromagnetic flowmeter 205 and a solenoid valve 206.

[0032] Furthermore, the power supply unit 3 includes a plasma power supply 301 , one side of the plasma power supply 301 is electrically connected to a voltage regulator 302 , and the other side of the plasma power supply 301 is fixedly connected to an oscilloscope 303 .

[0033] In addition, the alkali solution treatment unit 4 includes an alkali solution treatment tank 401, the top of which is fixedly connected with an air outlet pipe 402, the alkali solution treatment tank 401 is filled with alkali solution, and the right air pipe of the DBD reactor 1 is inserted into the alkali solution.

[0034] The honeycomb ceramic plasma degradation method for SF6 comprises the following specific steps: S1: clamp the inner electrode tube 1024 into the inner electrode tube hole 1021 so that the honeycomb ceramic 1023 is located in the middle of the inner electrode tube 1024; S2: Prepare 8.46g of Cu(NO3)2 powder, add 150ml of water to the Cu(NO3)2 powder, and stir it evenly without precipitation to obtain a Cu(NO3)2 aqueous solution; S3: The detachable honeycomb ceramic inner electrode 102 is completely immersed in a Cu(NO3)2 aqueous solution, evaporated in a 100°C water bath, and then placed in a 150°C oven for 8 hours to completely evaporate its water, and finally placed in a tube furnace for high temperature calcination at 500°C for 4 hours to make the CuO catalyst evenly attached to the catalyst pores 1022; CuO will evenly adhere to the porous channels of the honeycomb ceramic 1023. Through the synergistic effect of DBD plasma technology and catalysts, the efficient degradation of SF6 waste gas can be achieved, and the degradation products tend to generate SO2 that is easy to handle. After alkaline solution treatment, it can be directly discharged, which can reduce pollution to the environment. It is an efficient and environmentally friendly waste gas treatment technology. The presence of CuO can significantly improve the degradation rate of SF6 and has a certain product selectivity, making the SF6 degradation products more inclined to produce SO2 and other easy-to-handle substances, and effectively inhibiting the generation of other difficult-to-handle products such as SOF2, SO2F2 and SOF4.

[0035] S4: The outer electrode 101 is sleeved on the outer surface of the detachable honeycomb ceramic inner electrode 102, and the two ends of the outer electrode 101 are connected to the gas distribution device 201 and the alkali solution treatment tank 401 using the flange 104, and the outer electrode 101 is connected to the plasma power supply 301 using a high-voltage wire; S5: SF6 gas supply bottle 202 and Ar gas supply bottle 203 are connected to gas distributor 201 through gas pipes, and voltage regulator 302 and oscilloscope 303 are connected to plasma power supply 301 through wires; S6: Open the pressure reducing valve 204 at the gas pipes of the SF6 gas supply bottle 202 and the Ar gas supply bottle 203, and control the input opening of SF6 and Ar through the pressure reducing valve 204. According to the SF6 and Ar ratio set by the gas distributor 201, the ratio is 2% SF6 and 98% Ar, and fully mix them inside the gas distributor to form a uniform mixed gas; S7: The mixed gas flow rate is controlled by the electromagnetic flowmeter 205 and the electromagnetic valve 206 at a flow rate of 300 ml / min, and the mixed gas is delivered to the DBD reactor 1; S8: Start the plasma power supply 301, the discharge gap is 3mm, under the action of the high voltage electric field, the mixed gas in the catalyst hole 1022 is broken down to generate plasma, and the active substances such as high-energy electrons, ions and free radicals in the plasma collide and react with SF6 molecules. The CuO catalyst synergistically plays a catalytic role in the plasma environment to promote the degradation process of SF6 gas; S9: After degradation, first close the pressure reducing valve 204 at the SF6 gas supply bottle 202 to keep the DBD reactor 1 running stably. After 10 minutes, turn off the plasma power supply 301 and continue to introduce Ar to discharge the gas in the DBD reactor 1 into the alkali solution in the alkali solution treatment tank 401, treat the tail gas, and discharge it through the outlet pipe 402; the tail gas is treated in the alkali solution treatment tank 401 and then discharged into the atmosphere, which can effectively avoid the impact on human body and environment.

[0036] S10: Finally, close the pressure reducing valve 204 at the Ar gas supply bottle 203.

[0037] Table 2 Experimental data of the ratio of Cu(NO3)2 powder mass to aqueous solution volume of 8.46g:150ml

[0038] In summary, the honeycomb ceramic plasma degradation device for SF6 proposes a detachable honeycomb ceramic inner electrode structure, whose porous channels are conducive to uniform gas distribution and catalyst adsorption. CuO is uniformly attached to the porous channels of the honeycomb ceramic inner electrode by water bath evaporation and other methods. The CuO catalyst can reduce the activation energy required for SF6 dissociation and accelerate the degradation reaction. The degradation rate of SF6 can be significantly improved through the catalytic effect of CuO and the enhancement effect of DBD plasma. At the same time, the presence of CuO catalyst enables SF6 to reduce the generation of harmful products in the degradation products, which can effectively improve the content distribution of degradation products. In addition, the device does not produce secondary pollution during the degradation of SF6, which meets environmental protection requirements.

[0039] Moreover, the tail gas is discharged into the atmosphere after being treated in the alkaline solution treatment tank 401, which can effectively avoid the impact on human body and environment. This technical solution breaks the traditional single inner electrode structure and catalyst attachment method, uses honeycomb ceramic as the inner electrode material, and its porous channels can be used as the attachment point of CuO catalyst, and realizes the efficient degradation of SF6 under the synergistic effect of plasma and catalyst. At the same time, the product SO2 obtained by the degradation of CuO catalyst has a large content, which is easy to handle and will not cause harm to human body and environment through absorption by alkaline solution.

[0040] Example 3: Please refer to Figure 1-7 A honeycomb ceramic plasma SF6 degradation device includes a DBD reactor 1, a gas supply unit 2 is arranged on the left side of the DBD reactor 1, a power supply unit 3 is arranged at the bottom of the DBD reactor 1, and a processing unit 4 is arranged on the right side of the DBD reactor 1.

[0041] The DBD reactor 1 is connected to the gas supply unit 2 through an air pipe, the DBD reactor 1 is electrically connected to the power supply unit 3, and the DBD reactor 1 is connected to the processing unit 4 through an air pipe. The DBD reactor 1 includes an outer electrode 101, and a detachable honeycomb ceramic inner electrode 102 is clamped inside the outer electrode 101. The detachable honeycomb ceramic inner electrode 102 is composed of a honeycomb ceramic 1023 and an inner electrode tube 1024. An inner electrode tube hole 1021 is provided inside the honeycomb ceramic 1023, and a catalyst hole 1022 is provided inside the honeycomb ceramic 1023. The inner electrode tube 1024 is clamped inside the inner electrode tube hole 1021, and the size of the inner electrode tube hole 1021 is larger than the size of the catalyst hole 1022. The structure of the honeycomb ceramic 1023 has a large specific surface area and porosity, which is conducive to uniform distribution and flow of gas. At the same time, the porous structure can be used as a carrier of the catalyst. This structural design can effectively improve the SF6 degradation efficiency. In addition, the main component of honeycomb ceramics is Al2O3, which can provide more active sites for the catalyst and accelerate the degradation reaction. Because the CuO catalyst has excellent catalytic activity, it can catalyze the decomposition of SF6 molecules, reduce the activation energy of the reaction, accelerate the degradation reaction, and the degradation products tend to generate SO2 and other substances that are easy to handle.

[0042] In addition, a sealing connector 103 is provided on the outer surface of the outer electrode 101, and the sealing connector 103 is used to seal the gas supply unit 2 and the gas pipe of the processing unit 4. The number of the inner electrode tube hole 1021 is one, and the diameter of the inner electrode tube hole 1021 is 0.6 cm. The number of the catalyst holes 1022 is eight, and the diameter of the eight catalyst holes 1022 is 0.4 cm. The eight catalyst holes 1022 are evenly distributed on the outer surface of the inner electrode tube hole 1021 in a ring shape, and the length of the inner electrode tube 1024 is 35 cm.

[0043] Secondly, the gas supply unit 2 includes a gas distributor 201, the gas inlet of the gas distributor 201 is connected to the SF6 gas supply bottle 202 and the Ar gas supply bottle 203 through a gas pipe, the outer surface of the gas pipe connecting the SF6 gas supply bottle 202, the Ar gas supply bottle 203 and the gas distributor 201 is provided with a pressure reducing valve 204, and the outer surface of the gas pipe connecting the gas distributor 201 and the DBD reactor 1 is provided with an electromagnetic flowmeter 205 and a solenoid valve 206.

[0044] Furthermore, the power supply unit 3 includes a plasma power supply 301 , one side of the plasma power supply 301 is electrically connected to a voltage regulator 302 , and the other side of the plasma power supply 301 is fixedly connected to an oscilloscope 303 .

[0045] In addition, the alkali solution treatment unit 4 includes an alkali solution treatment tank 401, the top of which is fixedly connected with an air outlet pipe 402, the alkali solution treatment tank 401 is filled with alkali solution, and the right air pipe of the DBD reactor 1 is inserted into the alkali solution.

[0046] The honeycomb ceramic plasma degradation method for SF6 comprises the following specific steps: S1: clamp the inner electrode tube 1024 into the inner electrode tube hole 1021 so that the honeycomb ceramic 1023 is located in the middle of the inner electrode tube 1024; S2: Prepare 11.28g of Cu(NO3)2 powder, add 150ml of water to the Cu(NO3)2 powder, and stir it evenly without precipitation to obtain a Cu(NO3)2 aqueous solution; S3: The detachable honeycomb ceramic inner electrode 102 is completely immersed in a Cu(NO3)2 aqueous solution, evaporated in a 100°C water bath, and then placed in a 150°C oven for 8 hours to completely evaporate its water, and finally placed in a tube furnace for high temperature calcination at 500°C for 4 hours, so that the CuO catalyst will be uniformly attached to the catalyst pores 1022; CuO will be uniformly attached to the porous channels of the honeycomb ceramic 1023. Through the synergistic effect of DBD plasma technology and catalysts, the efficient degradation of SF6 waste gas can be achieved, and the degradation products tend to generate SO2 that is easy to handle. After alkaline solution treatment, it can be directly discharged, which can reduce pollution to the environment. It is an efficient and environmentally friendly waste gas treatment technology. The presence of CuO can significantly improve the degradation rate of SF6 and has a certain product selectivity, so that the SF6 degradation products are more inclined to produce SO2 and other easy-to-handle substances, and effectively inhibit the generation of other difficult-to-handle products such as SOF2, SO2F2 and SOF4.

[0047] S4: The outer electrode 101 is sleeved on the outer surface of the detachable honeycomb ceramic inner electrode 102, and the two ends of the outer electrode 101 are connected to the gas distribution device 201 and the alkali solution treatment tank 401 using the flange 104, and the outer electrode 101 is connected to the plasma power supply 301 using a high-voltage wire; S5: SF6 gas supply bottle 202 and Ar gas supply bottle 203 are connected to gas distributor 201 through gas pipes, and voltage regulator 302 and oscilloscope 303 are connected to plasma power supply 301 through wires; S6: Open the pressure reducing valve 204 at the gas pipes of the SF6 gas supply bottle 202 and the Ar gas supply bottle 203, and control the input opening of SF6 and Ar through the pressure reducing valve 204. According to the SF6 and Ar ratio set by the gas distributor 201, the ratio is 2% SF6 and 98% Ar, and fully mix them inside the gas distributor to form a uniform mixed gas; S7: The mixed gas flow rate is controlled by the electromagnetic flowmeter 205 and the electromagnetic valve 206 at a flow rate of 300 ml / min, and the mixed gas is delivered to the DBD reactor 1; S8: Start the plasma power supply 301, the discharge gap is 3mm, under the action of the high voltage electric field, the mixed gas in the catalyst hole 1022 is broken down to generate plasma, and the active substances such as high-energy electrons, ions and free radicals in the plasma collide and react with SF6 molecules. The CuO catalyst synergistically plays a catalytic role in the plasma environment to promote the degradation process of SF6 gas; S9: After degradation, first close the pressure reducing valve 204 at the SF6 gas supply bottle 202 to keep the DBD reactor 1 running stably. After 10 minutes, turn off the plasma power supply 301 and continue to introduce Ar to discharge the gas in the DBD reactor 1 into the alkali solution in the alkali solution treatment tank 401, treat the tail gas, and discharge it through the outlet pipe 402; the tail gas is treated in the alkali solution treatment tank 401 and then discharged into the atmosphere, which can effectively avoid the impact on human body and environment.

[0048] S10: Finally, close the pressure reducing valve 204 at the Ar gas supply bottle 203.

[0049] Table 3 Experimental data of the ratio of Cu(NO3)2 powder mass to aqueous solution volume of 11.28g:150ml

[0050] In summary, the honeycomb ceramic plasma degradation device for SF6 proposes a detachable honeycomb ceramic inner electrode structure, whose porous channels are conducive to uniform gas distribution and catalyst adsorption. CuO is uniformly attached to the porous channels of the honeycomb ceramic inner electrode by water bath evaporation and other methods. The CuO catalyst can reduce the activation energy required for SF6 dissociation and accelerate the degradation reaction. The degradation rate of SF6 can be significantly improved through the catalytic effect of CuO and the enhancement effect of DBD plasma. At the same time, the presence of the CuO catalyst can reduce the generation of harmful products in the degradation products, which can effectively improve the content distribution of the degradation products. In addition, the device does not produce secondary pollution during the degradation of SF6, which meets environmental protection requirements.

[0051] Moreover, the tail gas is discharged into the atmosphere after being treated in the alkaline solution treatment tank 401, which can effectively avoid the impact on human body and environment. This technical solution breaks the traditional single inner electrode structure and catalyst attachment method, uses honeycomb ceramic as the inner electrode material, and its porous channels can be used as the attachment point of CuO catalyst, and realizes the efficient degradation of SF6 under the synergistic effect of plasma and catalyst. At the same time, the product SO2 obtained by the degradation of CuO catalyst has a large content, which is easy to handle and will not cause harm to human body and environment through absorption by alkaline solution.

[0052] When the volume of aqueous solution was 150 ml, comparative experiments were conducted under different Cu(NO3)2 powder masses. After multiple groups of experimental comparisons, it was found that when the mass of Cu(NO3)2 powder was 5.64 g, the concentration of Cu(NO3)2 powder in the solution was too low, so that the CuO after subsequent water bath evaporation and high-temperature calcination could not be completely attached to the porous channels of the honeycomb ceramics, resulting in the maximum SF6 degradation rate of only 77.6%; when the mass of Cu(NO3)2 powder was 11.28 g, the concentration of the aqueous solution configured may be too high, which will cause partial crystallization during the water bath evaporation process, which will affect the experimental results. The maximum degradation rate was 78.9%; in summary, 8.46 g of Cu(NO3)2 powder was selected and mixed with 150 ml of water to prepare Cu(NO3)2 aqueous solution. When the power input power was 100 W, the maximum degradation rate was 97.0%, SO2 accounted for the highest proportion of the degradation products, and most of the acidic gases could be directly absorbed by alkali solution.

[0053] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A honeycomb ceramic plasma degradation device for SF6, comprising a DBD reactor (1), characterized in that: A gas supply unit (2) is arranged on the left side of the DBD reactor (1), a power supply unit (3) is arranged at the bottom of the DBD reactor (1), and a processing unit (4) is arranged on the right side of the DBD reactor (1); The DBD reactor (1) is connected to the gas supply unit (2) via an air pipe, the DBD reactor (1) is connected to the power supply unit (3) via an electrical connection, and the DBD reactor (1) is connected to the processing unit (4) via an air pipe; The DBD reactor (1) comprises an outer electrode (101), a detachable honeycomb ceramic inner electrode (102) is clamped inside the outer electrode (101), the detachable honeycomb ceramic inner electrode (102) is composed of a honeycomb ceramic (1023) and an inner electrode tube (1024), an inner electrode tube hole (1021) is provided inside the honeycomb ceramic (1023), a catalyst hole (1022) is provided inside the honeycomb ceramic (1023), the inner electrode tube (1024) is clamped inside the inner electrode tube hole (1021), and the size of the inner electrode tube hole (1021) is larger than the size of the catalyst hole (1022); The outer surface of the outer electrode (101) is provided with a sealing connection piece (103), and the sealing connection piece (103) is used to seal the air pipe of the air supply unit (2) and the processing unit (4).

2. The honeycomb ceramic plasma degradation device of SF6 according to claim 1 is characterized in that: The gas supply unit (2) comprises a gas distributor (201); a gas inlet of the gas distributor (201) is connected to an SF6 gas supply bottle (202) and an Ar gas supply bottle (203) via a gas pipe; a pressure reducing valve (204) is provided on the outer surface of the gas pipe connecting the SF6 gas supply bottle (202), the Ar gas supply bottle (203) and the gas distributor (201); an electromagnetic flowmeter (205) and an electromagnetic valve (206) are provided on the outer surface of the gas pipe connecting the gas distributor (201) and the DBD reactor (1).

3. The honeycomb ceramic plasma degradation device of SF6 according to claim 1 is characterized in that: The power supply unit (3) comprises a plasma power supply (301), one side of the plasma power supply (301) is electrically connected to a voltage regulator (302), and the other side of the plasma power supply (301) is fixedly connected to an oscilloscope (303).

4. The honeycomb ceramic plasma degradation device of SF6 according to claim 1 is characterized in that: The alkali liquid treatment unit (4) comprises an alkali liquid treatment tank (401), the top of the alkali liquid treatment tank (401) is fixedly connected to an air outlet pipe (402), the alkali liquid treatment tank (401) is filled with alkali liquid, and the right air pipe of the DBD reactor (1) is inserted into the alkali liquid.

5. The honeycomb ceramic plasma degradation device of SF6 according to claim 1, characterized in that: The catalyst holes (1022) are evenly distributed in a ring shape on the outer surface of the inner electrode tube hole (1021).

6. The honeycomb ceramic plasma degradation device of SF6 according to claim 1, characterized in that: The sealing connection piece (103) is a flange.

7. The method for degrading SF6 by using honeycomb ceramic plasma according to any one of claims 1 to 6, characterized in that: The specific steps are: S1: clamping the inner electrode tube (1024) into the inner electrode tube hole (1021) so that the honeycomb ceramic (1023) is located in the middle of the inner electrode tube (1024); S2: Prepare Cu(NO3)2 powder, add water to the Cu(NO3)2 powder, and stir it evenly without precipitation to obtain a Cu(NO3)2 aqueous solution; S3: completely immersing the detachable honeycomb ceramic inner electrode (102) in a Cu(NO3)2 aqueous solution, evaporating it in a water bath, and calcining it at high temperature to decompose it into a CuO catalyst, which is uniformly attached to the catalyst pores (1022); S4: The outer electrode (101) is sleeved onto the outer surface of the detachable honeycomb ceramic inner electrode (102), and the two ends of the outer electrode (101) are connected to the gas distribution device (201) and the alkali solution treatment tank (401) using the flange (104), and the outer electrode (101) is connected to the plasma power supply (301) using a high-voltage wire; S5: The SF6 gas supply bottle (202) and the Ar gas supply bottle (203) are connected to the gas distribution device (201) via a gas pipe, and the voltage regulator (302) and the oscilloscope (303) are connected to the plasma power supply (301) via electric wires; S6: opening the pressure reducing valve (204) at the gas pipes of the SF6 gas supply bottle (202) and the Ar gas supply bottle (203), controlling the input opening of SF6 and Ar through the pressure reducing valve (204), mixing the SF6 and Ar inside the gas distributor (201) according to the ratio of SF6 and Ar set by the gas distributor (201), and forming a uniform mixed gas; S7: Controlling the flow rate of the mixed gas by combining the electromagnetic flow meter (205) and the electromagnetic valve (206) to deliver the mixed gas into the DBD reactor (1); S8: starting the plasma power supply (301), under the action of the high voltage electric field, the mixed gas in the catalyst hole (1022) is broken down to generate plasma, and active substances such as high-energy electrons, ions and free radicals in the plasma collide and react with SF6 molecules, and the CuO catalyst synergistically plays a catalytic role in the plasma environment to promote the degradation process of SF6 gas; S9: After degradation, first close the pressure reducing valve (204) at the SF6 gas supply bottle (202) to keep the DBD reactor (1) running stably. After 10 minutes, turn off the plasma power supply (301) and continue to introduce Ar to discharge the gas in the DBD reactor (1) into the alkali solution in the alkali solution treatment pool (401) for tail gas treatment and discharge through the gas outlet pipe (402); S10: Finally, close the pressure reducing valve (204) at the Ar gas supply bottle (203).

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