Plasma coupling fluidized catalyst device

Abstract

The invention provides a plasma coupling fluidized catalyst device which is characterized in that a first conical quartz tube is arranged in the middle of an inner medium tube, a first cylindrical quartz tube is arranged at the upper end of the inner medium tube, a second cylindrical quartz tube is arranged at the lower end of the inner medium tube, a high-voltage electrode covers the outer wall of the conical quartz tube, and an inner ground electrode is arranged in the inner medium tube; the inner ground electrode comprises a cylindrical metal rod and a conical metal rod, an air outlet is formed in the outer medium pipe, the outer ground electrode covers the outer wall of the outer medium pipe, and the bottom end air inlet device is arranged in the bottom end of the outer medium pipe. According to the invention, gas molecules are helped to reach a vibration excitation state, and conversion of the gas molecules is promoted. Compared with other dielectric barrier discharge devices, heat generated by discharge of the dielectric barrier discharge device is beneficial to activation of a catalyst, and an integrated air inlet device is used, so that all airflow is sprayed out through micro-inclined capillary micropores and acts on floating of the catalyst more accurately, and loss of air pressure is reduced. The device has low requirements on the material and temperature of the reactor, and realizes efficient conversion of the benzene ring-containing compound gas within a short time.

Description

Technical Field

[0001] The invention belongs to the application field of plasma and relates to a plasma coupled fluidized catalyst device. Background Art

[0002] Among many renewable energy sources, biomass energy shows great application potential due to its abundant reserves and low pollutant emissions. At present, the main ways to utilize biomass resources include pyrolysis, gasification and other methods, through which high calorific value biomass synthesis gas can be prepared. However, in the process of biomass pyrolysis and gasification, incomplete cracking of biomass raw materials will produce a large number of by-products, which are difficult to be fully utilized. Their existence will not only reduce the utilization efficiency of biomass, but also cause pipeline corrosion or blockage. Therefore, the removal and utilization of biomass tar is of great significance to improving the utilization efficiency of biomass and ensuring the safe operation of the biomass pyrolysis and gasification process.

[0003] At present, the gas product removal technologies for organic compounds containing benzene rings mainly include physical methods and chemical methods. The physical method mainly uses water washing, filtration and other means. Among them, the water washing method uses water to fully contact with the synthesis gas, so that the tar is gradually condensed and removed from the gas phase due to the decrease in temperature. This method has the advantages of simple process and low operating cost, but there are problems such as secondary pollution, difficulty in recycling wastewater and low single-stage removal efficiency. The filtration method relies on high-efficiency filter materials such as ceramics to adsorb and remove tar. Although it has the advantages of no secondary pollution and high removal efficiency, the equipment operation resistance is large, resulting in high energy consumption. The chemical method mainly uses high-temperature cracking technology. The high-temperature cracking process relies on high temperature conditions to enable large molecular substances to generate small molecular gases through reactions such as bond breaking and dehydrogenation. Usually, this method needs to be operated in an environment above 900°C to ensure that the tar is fully cracked.

[0004] The method described in patent CN114272858A has low energy of two electrodes and low conversion rate, and because of its low reaction temperature, the activity of the catalyst is not fully activated, which affects the synergistic effect of the reaction.

[0005] Although the method described in patent CN117065672A realizes the fluidization of the catalyst through the Lorentz force and the push of the gas, it can only use weakly magnetic catalysts and cannot flexibly select more efficient catalysts for different reactants; In the device described in patent CN118652714A, the synergistic effect of catalyst stacking filling is poor, and the active sites of some catalysts are not exposed to the plasma; The device described in patent CN118543302A places the catalyst through a gas distribution plate, but the plate mesh has a strong barrier effect on the gas, and the gas acts on a smaller portion of the catalyst, resulting in a reduced fluidization effect.

[0006] Although the device described in patent CN113413835A increases the area of ​​the reaction chamber by external jet discharge, it has high energy consumption and complex equipment. It requires five air inlets to intake air simultaneously to achieve the expected effect. Additional products will be produced during the reaction, resulting in increased product complexity. Summary of the invention

[0007] 1. Technical problems to be solved: The invention provides a method which can effectively utilize the energy of an organic compound gas containing a benzene ring without generating secondary pollution and can realize low-cost and high-efficiency treatment.

[0008] 2. Technical solution: In order to solve the above problems, the present invention provides a plasma-coupled fluidized catalyst device, comprising a coaxial outer medium tube and an inner medium tube, an outer ground electrode and an outer wall of the outer medium tube are tightly fitted, an inner wall of the high-voltage electrode and an outer wall of the inner medium tube are tightly fitted, the outer medium tube and the inner medium tube are sealed inside, the middle of the inner medium tube is a first conical quartz tube, the upper end is a first cylindrical quartz tube, and the lower end is a second cylindrical quartz tube, the high-voltage electrode is covered on the outer wall of the conical quartz tube and is coaxially placed, the inner electrode is placed inside the inner medium tube, the inner electrode comprises a cylindrical metal rod and a conical metal rod, the conical metal rod is tightly fitted and coaxially placed with the conical quartz tube, the cylindrical metal rod is located above the conical metal rod and has a smaller diameter than the cylindrical quartz tube, an air outlet is provided on the outer medium tube, a bottom air inlet device is placed inside the bottom end of the outer medium tube, and a catalyst is placed between the outer medium tube and the inner medium tube.

[0009] The included angle between the bottom end of the first conical quartz tube and the top end of the second cylindrical quartz tube is 75-88°.

[0010] The middle of the external medium tube is a second conical quartz tube, the upper end is a third cylindrical quartz tube, and the lower end is a fourth cylindrical quartz tube. The external electrode is covered on the outer wall of the second conical quartz tube, and the air outlet is arranged on the third cylindrical quartz tube.

[0011] The included angle between the bottom end of the second conical quartz tube and the top end of the fourth cylindrical quartz tube is 75-88°.

[0012] The inclination angle of the catalyst is the same as the included angle between the bottom end of the second conical quartz tube and the top end of the fourth cylindrical quartz tube.

[0013] The bottom air intake device comprises a capillary air outlet hole arranged at the top, an air inlet at the bottom and an air intake structure connecting the capillary air outlet hole and the air inlet, and the catalyst is placed on the surface of the capillary air outlet hole.

[0014] A groove is provided in the middle of the capillary vent, and the second cylindrical quartz tube of the inner medium tube is inserted into the groove and fits tightly, so that the outer medium tube and the inner medium tube remain coaxial. The air intake structure has large openings at the air inlet and the opening connecting the capillary vent, and is narrow in the middle.

[0015] It also includes a sealing device, which includes an external sealing fixture, a bottom sealing fixture and an internal sealing fixture located below the external sealing fixture. The external sealing fixture is sleeved on the external top end of the external medium tube and a rubber ring is added to seal the inside of the external medium tube; the internal sealing fixture is sleeved on the external top end of the inner medium tube and a rubber ring is added to seal the inside of the inner medium tube. The bottom air intake device is fixed by the bottom sealing fixture.

[0016] The external sealing fixing device and the internal sealing fixing device have the same structure, and are, from top to bottom, a medium tube fixing part, a first intermediate connecting part and a first electrode fixing part. The interior of the medium tube fixing part is a first hollow part, with an opening at the lower end and a first hole at the upper part. The inner wall of the first hollow part and the inner wall of the first hole are both provided with threads. The upper and lower ends of the first intermediate connecting part are provided with cylindrical protrusions, the middle part is a second hollow part, and a second hole is provided in the middle of the two protrusions. The inner wall of the second hole, the outer wall of the upper protrusion, and the outer wall of the lower protrusion are all provided with threads. The first hole and the second hole are concentric and have the same inner diameter. The outer wall of the upper protrusion of the first intermediate connecting part and the inner wall of the first hollow part of the medium tube fixing part are both provided with threads. The first electrode fixing part has a third hole inside, the inner wall of the third hole is provided with a thread and matches the thread of the outer wall protruding below the first intermediate connecting part, a fourth hole is provided below the third hole which is concentric and has an inner diameter smaller than the third hole, the threads of the first hole and the second hole match the threads of the cylindrical metal rod in the inner electrode, the second hollow and the inner diameter of the fourth hole of the external sealing fixture match the outer diameter of the third cylindrical quartz tube of the external medium tube, the second hollow and the inner diameter of the fourth hole of the internal sealing fixture match the outer diameter of the first cylindrical quartz tube of the inner medium tube, and the second hollow of the first intermediate connecting part of the external sealing fixture is provided with a high-voltage electrode outlet hole.

[0017] The bottom sealing and fixing device includes a medium tube connecting part and an air intake part located below the medium tube connecting part. The interior of the medium tube connecting part is a third hollow, the lower end is open, and a fifth hole is opened on the upper part. The inner wall of the third hollow is provided with a thread. A cylindrical protrusion is arranged on the upper end of the air intake part. The outer wall of the cylindrical protrusion is provided with a thread matching the thread of the inner wall of the third hollow. A sixth hole concentric with the fifth hole and having the same inner diameter as the fifth hole is opened in the middle of the protrusion. An air intake side port is arranged on the side of the air intake part. A seventh hole concentric with the sixth hole and having an inner diameter smaller than that of the sixth hole is arranged below the sixth hole. The sixth and seventh holes do not penetrate the air intake part. The aperture of the fifth hole matches the outer diameter of the fourth cylindrical quartz tube in the outer medium tube, and the aperture of the seventh hole matches the outer diameter of the second cylindrical quartz tube in the inner medium tube.

[0018] 3. Beneficial effects: Compared with two electrodes, the present invention has higher energy, helps gas molecules reach a vibrational excited state, and promotes the transformation of gas molecules.

[0019] The present invention adopts a conical fluidized bed as a reactor, and its conical structure is helpful for the separation of fine particles and the increase of residence time, and is helpful for the catalyst and plasma to act synergistically on the raw gas, thereby increasing the conversion rate of the gas.

[0020] Compared with other devices with dielectric barrier discharge structures, the present invention has higher thermal energy under the same reaction conditions, which is helpful for the activation of the catalyst and avoids the phenomenon that the active sites of the catalyst are not fully activated due to low temperature, resulting in a decrease in the synergistic effect.

[0021] The present invention uses an integrated air intake device to allow all airflow to be ejected through slightly inclined capillary pores, so as to more accurately act on the catalyst floating and reduce the loss of gas pressure.

[0022] The inner electrode of the present invention is completely isolated in the inner medium tube, thus avoiding the problem of reactor breakdown caused by excessive local carbon deposition due to the reaction of gas entering the inner medium tube, and facilitating the stable progress of the reaction.

[0023] Compared with traditional gas treatment methods, this device has lower requirements on reactor materials and temperature, and can achieve efficient conversion in a shorter time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the device used for tar treatment.

[0025] Figure 2 It is a cross-sectional view of the device of the present invention.

[0026] Figure 3 This is a disassembly diagram of the device.

[0027] Figure 4 It is a schematic diagram of the structure of the external medium tube.

[0028] Figure 5 It is a schematic diagram of the inner medium tube structure.

[0029] Figure 6 It is a schematic diagram of the inner electrode structure.

[0030] Figure 7 It is a schematic diagram of the high voltage electrode structure.

[0031] Figure 8 It is a schematic diagram of the external electrode structure.

[0032] Fig. 9 It is a schematic diagram of the structure of the bottom air intake device.

[0033] Fig.10 It is a schematic diagram of the structure of an external sealing fixture and an internal sealing fixture.

[0034] Fig.11 It is a schematic diagram of the structure of the bottom sealing fixture.

[0035] Fig.12 It is the conversion rate of tar under different dielectric barrier discharge device structures.

[0036] Fig.13 is the conversion rate of methane and carbon dioxide under different dielectric barrier discharge device structures Fig.14 is the reactor temperature under different dielectric barrier discharge device structures.

[0037] Fig.15 It is the floating height of the catalyst using different air intake methods at different flow rates.

[0038] Explanation of reference numerals: 1. External sealing fixture; 101. Medium tube fixing portion; 102. First intermediate connecting portion; 103. First electrode fixing portion; 1101. First hole; 1102. First hollow; 1201. Second hole; 1202. Upper raised outer wall; 1203. Lower raised outer wall; 1204. High-voltage electrode outlet hole; 1205. Second hollow; 1301. Third hole; 1302: Fourth hole; 2. Internal sealing fixture; 3. Gas outlet hole; 4. External medium tube; 401. First cylindrical quartz tube; 402. First conical quartz tube; 403. Second cylindrical quartz tube; 5. Internal medium tube; 501. Third cylindrical quartz tube, 502. Second conical quartz tube; 503. The third cylindrical quartz tube; 6. the inner electrode; 601. the cylindrical metal rod; 602. the conical metal rod; 7. the catalyst; 8. the outer electrode; 9. the high-voltage electrode; 10. the bottom air inlet device; 1001. the capillary vent; 1002. the groove; 1003. the air inlet structure; 1004. the air inlet; 11. the bottom sealing fixture; 111; the medium tube connecting part; 112. the air inlet part; 11101 the fifth hole; 11102. the third hollow; 11201. the outer wall of the cylindrical protrusion; 11202. the sixth hole; 11203. the seventh hole; 11204. the air inlet side port. DETAILED DESCRIPTION

[0039] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0040] like Figure 1-Figure 3 As shown, a plasma coupled fluidized catalyst device comprises a coaxial outer medium tube 4 and an inner medium tube 5, an outer ground electrode 8 is closely fitted to the outer wall of the outer medium tube 4, an inner wall of a high voltage electrode 9 is closely fitted to the outer wall of the inner medium tube 5, and the outer medium tube 4 and the inner medium tube 5 are sealed inside. The middle of the inner medium tube 5 is a first conical quartz tube 502, as shown in FIG. Figure 5 As shown, the upper end is a first cylindrical quartz tube 501, and the lower end is a second cylindrical quartz tube 503. The high-voltage electrode is covered on the outer wall of the conical quartz tube 502 and is coaxially placed. The inner electrode 6 is placed inside the inner medium tube 5. The inner electrode 6 includes a cylindrical metal rod 601 and a conical metal rod 602. The conical metal rod 602 is tightly fitted with the conical quartz tube 502 and is coaxially placed. The cylindrical metal rod 601 is located above the conical metal rod 602 and has a smaller diameter than the cylindrical quartz tube 501. The outer medium tube 4 is provided with an air outlet 3, and the bottom air inlet device 10 is placed inside the bottom end of the outer medium tube 4. The catalyst 7 is placed between the outer medium tube 4 and the inner medium tube 5.

[0041] The present invention is a conical three-electrode dielectric barrier discharge device for processing. Under the drive of a pulse power supply or an AC power supply, an alternating electric field is generated between the inner electrode 6 and the high-voltage electrode 9 due to the voltage difference. Under the obstruction of the inner dielectric tube 5, a surface discharge in a dielectric barrier discharge occurs. The discharge occurs on the dielectric surface, and plasma is generated on the dielectric surface. The discharge path propagates along the dielectric surface. The electric field intensity is relatively large. The electrons accelerated by the high electric field collide with neutral molecules in the gas, and part of the energy is transferred to the molecules, so that the gas is easy to reach a vibration excited state and more likely to react. At the same time, the violent reaction of the surface discharge will generate more heat, which is conducive to the activation and cracking of gas molecules. An alternating electric field is also generated between the outer electrode 8 and the high-voltage electrode 9 due to the voltage difference. Under the obstruction of the outer dielectric tube 4, the gas in the gap is broken down to generate a body discharge in a dielectric barrier discharge. The discharge occurs in all gaps between the electrodes, the electric field is relatively uniform, the discharge volume is large, the generated plasma can fully contact with more gas, and the heat generated by the surface discharge will reduce the difficulty of gas breakdown, making body discharge easier to occur. At the same time, the active particles generated by the reaction continue to bombard subsequent gas molecules, which is conducive to improving the conversion efficiency of the gas. At this time, by controlling the gas flow rate, the catalyst is stably suspended in the discharge area, avoiding the inability of some active sites to act on gas molecules together with the plasma due to catalyst accumulation. At the same time, the high heat generated by the discharge helps to excite the active sites of the catalyst. The free radicals and excited molecules generated by the plasma interact with the surface of the catalyst 7, reducing the activation energy of the target reaction and making the reaction easier to proceed.

[0042] In one embodiment, the outer medium tube 4 is made of quartz material as a whole, and has a structure as follows: Figure 4 As shown, the middle of the external medium tube 4 is a second conical quartz tube 402, the upper end is a third cylindrical quartz tube 401, and the lower end is a fourth cylindrical quartz tube 403. The external electrode 8 is covered on the outer wall of the second conical quartz tube 402, and the air outlet 4 is arranged on the third cylindrical quartz tube 401.

[0043] In one embodiment, the third cylindrical quartz tube 401 is a cylindrical quartz tube with a length of 15mm~30mm, an outer diameter of 22~32mm, and a wall thickness of 0.5mm~1.5mm; the fourth cylindrical quartz tube 403 is a cylindrical quartz tube with a length of 10mm~25mm, an outer diameter of 10mm~20mm, and a wall thickness of 0.5mm~1.5mm; the second conical quartz tube 402 is 100mm~200mm high, with an outer diameter of 10mm~20mm at the bottom, an outer diameter of 22mm~32mm at the top, an angle of 75~88°, and a wall thickness of 0.5mm~1.5mm. The external electrode 8 covers the second conical quartz tube 402 and is coaxially placed.

[0044] In one embodiment, the inner medium tube 5 is made of quartz material as a whole. The first cylindrical quartz tube 501 is a cylindrical quartz tube with a length of 10mm~20mm, an outer diameter of 14mm~24mm, and a wall thickness of 0.5mm~1.5mm; the second cylindrical quartz tube 503 is a cylindrical quartz tube with a length of 2mm~6mm, an outer diameter of 2mm~12mm, and a wall thickness of 0.5mm~1.5mm; the first conical quartz tube 502 is 100mm~200mm high, with a bottom AQ outer diameter of 2mm~12mm, a top outer diameter of 14mm~24mm, a wall thickness of 0.5mm~1.5mm, and an angle of 75~88°. The high-voltage electrode 9 covers the first conical quartz tube 502 and is coaxially placed. The inner electrode 6 is placed inside the inner medium tube 5, and its conical part is tightly attached to the inner wall of 502 and coaxially placed. The inner medium tube 5 is coaxially placed with the outer medium tube 4.

[0045] In one embodiment, the inner electrode 6 is made entirely of copper or stainless steel, and has a structure such as Figure 6 As shown, 601 is a cylindrical metal rod, and 602 is a conical metal rod. The cylindrical metal rod 601 is a cylindrical metal rod with a length of 45 mm to 90 mm and a diameter of 2 mm to 8 mm, and the conical metal rod 602 is a conical metal rod with a height of 100 mm to 200 mm, a bottom diameter of 1 mm to 11 mm, a top diameter of 13 mm to 23 mm, and an angle of 75 to 88 degrees. The conical metal rod 602 is placed inside the inner medium tube 5 and fits tightly against the inner wall of the first conical quartz tube 502.

[0046] In one embodiment, the high voltage electrode 9 is made of copper or stainless steel and has a structure such as Figure 7 As shown, it is a conical tube or pipe network, the inner diameter of the bottom end is 2mm~12mm, the inner diameter of the top end is 14mm~24mm, the height is 50mm~150mm, the wall thickness is 0.1mm~0.4mm, the angle is 75~88°, and its inner wall is tightly fitted with the outer wall of the first conical quartz tube 502 in the inner medium tube 5 and is coaxially placed.

[0047] In one embodiment, Figure 8 As shown, the external electrode 8 is a conical tube or tube network made of copper or stainless steel, with an inner diameter of 10mm~20mm at the bottom, an inner diameter of 22mm~32mm at the top, a height of 50mm~150mm, an angle of 75~88°, a wall thickness of 0.1mm~0.4mm, and an inner wall thereof tightly fits with the second conical quartz tube 402 of the external medium tube 4 and is coaxially placed.

[0048] In one embodiment, Fig. 9As shown, the bottom air inlet device 10 is made of quartz, cylindrical in shape, with an outer diameter of 9.5mm~19.5mm and a length of 16mm~31mm. 1001 is a capillary outlet hole, the diameter of the capillary outlet hole 1001 is 0.5mm~1.5mm, and the catalyst 7 is placed on the surface of the capillary outlet hole 1001, and its inclination angle is the same as the angle of the outer medium tube 4, so that the air flow is ejected in the same direction, reducing the loss of gas flow rate, so that the catalyst 7 can float in the same direction, and enhance the fluidization effect of the catalyst 7. 1002 is a groove, and the second cylindrical quartz tube 503 of the inner medium tube 5 is inserted into the groove 1002 and fits tightly, so that the outer medium tube 4 and the inner medium tube 5 remain coaxial, and reduce the tip discharge between the inner electrode 6 and the high-voltage electrode 9, so that the reaction is more stable.

[0049] The air inlet structure 1003 connects the capillary outlet hole 1001 and the air inlet 1004. The air inlet structure 1003 has a large opening at the air inlet 1004 and the opening connecting the capillary outlet hole 1001, and is narrow in the middle. The gas entering from the air inlet 1004 reaches the capillary outlet hole 1001 more smoothly, reducing the turbulent loss during the gas transmission process, reducing the pressure loss of the gas, and facilitating the fluidization of the gas to the catalyst.

[0050] In one embodiment, the external sealing fixture 1 is sleeved on the external top of the external medium tube 4 and a rubber ring is added to seal the inside of the external medium tube 4; the internal sealing fixture 2 is sleeved on the external top of the internal medium tube 5 and a rubber ring is added to seal the inside of the internal medium tube 5. The bottom fixture 11 is sleeved on the external bottom of the external medium tube 4 and a rubber ring is added, and the bottom air intake device 10 is placed inside the bottom of the external medium tube 4 and is sealed and fixed by the bottom fixture 11, so that the entire device is in a sealed state.

[0051] In one embodiment, the external sealing fixture 1 and the internal sealing fixture 2 have the same structure. Fig.10As shown, from top to bottom are the medium tube fixing part 101, the first intermediate connecting part 102 and the first electrode fixing part 103, the interior of the medium tube fixing part 101 is a first hollow 1102, the lower end is open, and the upper part is provided with a first hole 1101, the inner wall of the first hollow 1102 and the inner wall of the first hole 1101 are both provided with threads, the upper and lower ends of the first intermediate connecting part 102 are provided with cylindrical protrusions, the middle part is a second hollow 1205, and the middle of the two protrusions is provided with a second hole 1201, the inner wall of the second hole 1201, the outer wall 1202 of the upper protrusion, and the outer wall 1203 of the lower protrusion are all provided with threads, the second hole 1201 and the second hole 1201 are concentric and have the same inner diameter, the second hollow 1205 of the first intermediate connecting part 102 is provided with a high-voltage electrode outlet hole 1204, the outer wall 1203 of the upper protrusion of the first intermediate connecting part 102 is provided with a high-voltage electrode outlet hole 1204, and the outer wall 1203 of the upper protrusion of the first intermediate connecting part 102 is provided with a high-voltage electrode outlet hole 1204. The thread of 202 matches the thread in the first hollow 1102 of the medium tube fixing part 101, the third hole 1301 is opened inside the first electrode fixing part 103, the inner wall of the third hole 1301 is provided with a thread and matches the thread of the outer wall 1203 protruding below the first intermediate connecting part 102, and a fourth hole 1302 is provided below the third hole 1301 that is concentric and has an inner diameter smaller than the third hole 1301, the threads of the first hole 1101 and the second hole 1201 match the threads of the cylindrical metal rod 601 in the inner electrode 6, the inner diameters of the second hollow 1205 and the fourth hole 1302 of the external sealing fixture 1 match the outer diameter of the third cylindrical quartz tube 401 of the external medium tube 4, and the inner diameters of the second hollow 1205 and the fourth hole 1302 of the internal sealing fixture 2 match the outer diameter of the first cylindrical quartz tube 501 of the inner medium tube 5.

[0052] The material of the external sealing fixture 1 is polytetrafluoroethylene. In the external sealing fixture 1, the cylindrical metal rod 601 in the inner electrode 6 passes through the second hole 1201 and then passes through the first hole 1101 and adds a thread to fix and seal the inner electrode 6; the third cylindrical quartz tube 401 in the external medium tube 4 passes through the fourth hole 1302 and then is inserted into the second hollow 1205, and a rubber ring is added to keep the entire structure airtight; 1204 is a high-voltage electrode outlet hole, and the high-voltage electrode is connected to the external power supply through the high-voltage electrode outlet hole 1204. The internal sealing fixture 2 is made of polytetrafluoroethylene. In the internal sealing fixture 2, the cylindrical metal rod in the inner electrode 6 passes through the second hole 1201 and then passes through the first hole 1101 and is threaded, so that the inner electrode 6 and the inner medium tube 5 are fixed and sealed; the first cylindrical quartz tube 501 in the inner medium tube 5 passes through the fourth hole 1302 and then is inserted into the second hollow 1205, and a rubber ring is added to keep the entire structure airtight to prevent the reaction gas from entering the inner medium tube to react and produce carbon deposits, resulting in unstable reaction.

[0053] In one embodiment, Fig.11 As shown, the bottom sealing fixture 11 includes a medium pipe connecting part 111 and an air inlet part 112 located below the medium pipe connecting part. The interior of the medium pipe connecting part 111 is a third hollow 11102, the lower end is open, and the upper part is provided with a fifth hole 11101. The inner wall of the third hollow 11102 is provided with a thread. A cylindrical protrusion is provided at the upper end of the air inlet part 112. The outer wall 11201 of the cylindrical protrusion is provided with a thread matching the thread of the inner wall of the third hollow 11102. A thread concentric with the fifth hole 11101 and having the same inner diameter as that of the inner wall of the third hollow 11102 is provided in the middle of the protrusion. The sixth hole 11202 is the same, an air inlet side port 11204 is provided on the side of the air inlet part 112, a seventh hole 11203 is provided below the sixth hole 11202 which is concentric with the sixth hole 11202 and has a smaller inner diameter than the sixth hole 11202, the sixth hole 11202 and the seventh hole 11203 do not penetrate the air inlet part 112, the aperture of the fifth hole 11101 matches the outer diameter of the fourth cylindrical quartz tube 403 in the outer medium tube 4, and the aperture of the seventh hole 11203 matches the outer diameter of the second cylindrical quartz tube 503 in the inner medium tube 5.

[0054] The bottom sealing fixture 11 is made of polytetrafluoroethylene, and the fourth cylindrical quartz tube portion in the external medium tube 4 is inserted into the sixth hole 11202 through the fifth hole 11101; the bottom air inlet device 10 passes through the internal medium tube to the seventh hole 11203, and is threaded through the sixth hole 11102 and the outer wall 11201 of the cylindrical protrusion to make the bottom airtight; 11204 is the air inlet side port, and the raw gas enters the reactor through the air inlet side port 11204, and is coupled with the catalyst after passing through the bottom air inlet device 10.

[0055] Taking tar treatment as an example, compared with the cone structure, Fig.12 and Fig.14 As shown in the figure, the conversion efficiency and temperature of the two-electrode device and the three-electrode device. Under the same reaction conditions, the conversion efficiency of the three-electrode device is significantly higher than that of the two-electrode device. This is attributed to the high energy, high reaction volume and high temperature of the three-electrode device, which makes the tar molecules more easily reacted and cracked.

[0056] Taking methane dry reforming as an example, the three-electrode plasma can produce gaseous products such as hydrogen, carbon monoxide and higher carbon chain alkanes, and can also produce liquid products such as alcohols and aldehydes.

[0057] like Fig.13As shown in the figure, the effects of the conical two electrodes and the conical three electrodes are compared. By introducing the control electrode, the three-electrode reactor can expand and stabilize the discharge area, make the plasma distribution more uniform, and increase the collision probability of gas molecules, thereby improving the reaction efficiency. In the methane dry reforming reaction, the optimized design of the three electrodes increases the electron temperature and electron density, so that more electron energy can be used to excite CH4 and CO2, so that the gas can reach the excited state required for the reaction, thereby improving the conversion rate of the raw gas. At the same time, the higher temperature in the three-electrode reaction area is conducive to the endothermic reaction of methane dry reforming, and can more fully activate the active sites of the catalyst to improve the synergistic effect.

[0058] The gas enters the device through the air inlet, suspends the catalyst 7, and is discharged from the air outlet after reacting with the plasma and the catalyst. In this reaction process, the suspension height of the catalyst 7 is one of the important conditions affecting the conversion rate. Under the same conditions, the higher the suspension height of the catalyst, the larger the distribution area, and the more interaction sites between the catalyst and the plasma, which can increase the number of active sites on the catalyst surface, thereby contributing to the formation of a synergistic effect between the plasma and the catalyst, and finally improving the overall performance of the reaction.

[0059] like Fig.15 As shown, the maximum height of catalyst suspension at different flow rates under different intake device structures is compared. From the figure, it can be seen that compared with using a flow equalizing plate and using the integrated intake device in this patent, the structure of this patent is more conducive to the suspension of the catalyst and can achieve a better synergistic catalytic effect.

[0060] This patent changes the electrode structure to generate two discharge modes, surface discharge and body discharge, in the reaction area to act together on the raw gas. The two discharge modes complement each other and cooperate with the fluidized catalyst to form an efficient coupling mode. At the same discharge length, the intensity of the plasma is enhanced and the interaction between the catalyst and the plasma is strengthened, which is beneficial to the generation of a synergistic effect between the plasma and the catalyst, thereby improving the overall conversion effect and performance.

Claims

1. A plasma coupled fluidized catalyst device, comprising a coaxial outer medium tube (4) and an inner medium tube (5), wherein an outer electrode (8) and an outer wall of the outer medium tube (4) are closely fitted, and an inner wall of a high voltage electrode (9) and an outer wall of the inner medium tube (5) are closely fitted, and the outer medium tube (4) and the inner medium tube (5) are internally sealed, characterized in that: The inner medium tube (5) has a first conical quartz tube (502) in the middle, a first cylindrical quartz tube (501) at the upper end, and a second cylindrical quartz tube (503) at the lower end. The high-voltage electrode is covered on the outer wall of the conical quartz tube (502) and is coaxially arranged. The inner electrode (6) is arranged inside the inner medium tube (5). The inner electrode (6) comprises a cylindrical metal rod (601) and a conical metal rod (602). The conical metal rod (602) and the conical quartz tube (502) are tightly fitted and coaxially arranged. The cylindrical metal rod (601) is located above the conical metal rod (602) and has a smaller diameter than the cylindrical quartz tube (501). The outer medium tube (4) is provided with an air outlet (3). The bottom air inlet device (10) is arranged inside the bottom end of the outer medium tube (4). The catalyst (7) is arranged between the outer medium tube (4) and the inner medium tube (5).

2. The plasma coupled fluidized catalyst device according to claim 1, characterized in that: The included angle between the bottom end of the first conical quartz tube (502) and the top end of the second cylindrical quartz tube (503) is 75-88°.

3. The plasma coupled fluidized catalyst device according to claim 1, characterized in that: The middle of the external medium tube (4) is a second conical quartz tube (402), the upper end is a third cylindrical quartz tube (401), and the lower end is a fourth cylindrical quartz tube (403); the external electrode (8) is covered on the outer wall of the second conical quartz tube (402), and the gas outlet (4) is arranged on the third cylindrical quartz tube (401).

4. The plasma-coupled fluidized catalyst device according to claim 3, characterized in that: The included angle between the bottom end of the second conical quartz tube (402) and the top end of the fourth cylindrical quartz tube (403) is 75-88°.

5. The plasma-coupled fluidized catalyst device according to claim 4, characterized in that: The inclination angle of the catalyst (7) is the same as the angle between the bottom end of the second conical quartz tube (402) and the top end of the fourth cylindrical quartz tube (403).

6. The plasma-coupled fluidized catalyst device according to claim 1, characterized in that: The bottom air intake device (10) comprises a capillary air outlet (1001) arranged at the top, an air inlet (1004) at the bottom, and an air intake structure connecting the capillary air outlet (1001) and the air inlet (1004), and the catalyst (7) is placed on the surface of the capillary air outlet (1001).

7. The plasma-coupled fluidized catalyst device according to claim 6, characterized in that: A groove (1002) is provided in the middle of the capillary vent (1001), and the second cylindrical quartz tube (503) of the inner medium tube (5) is inserted into the groove (1002) and fits tightly, so that the outer medium tube (4) and the inner medium tube (5) remain coaxial, and the air intake structure (1003) is large at the opening of the air inlet (1004) and the opening connecting the capillary vent (1001), and narrow in the middle.

8. The plasma-coupled fluidized catalyst device according to claims 3-5, characterized in that: The invention also comprises a sealing device, wherein the sealing device comprises an external sealing fixture (1), a bottom sealing fixture (11) and an internal sealing fixture (2) located below the external sealing fixture (1); the external sealing fixture (1) is sleeved on the external top end of the external medium tube (3) and a rubber ring is added to seal the inside of the external medium tube (4); the internal sealing fixture (2) is sleeved on the external top end of the internal medium tube (5) and a rubber ring is added to seal the inside of the internal medium tube (5); and the bottom air intake device (10) is fixed by the bottom sealing fixture (11).

9. The plasma-coupled fluidized catalyst device according to claim 8, characterized in that: The external sealing fixing device (1) and the internal sealing fixing device (2) have the same structure, and are composed of a medium tube fixing part (101), a first intermediate connecting part (102) and a first electrode fixing part (103) from top to bottom. The medium tube fixing part (101) has a first hollow space (1102) inside, an opening at the lower end, and a first hole (1101) at the upper part. The inner wall of the first hollow space (1102) and the inner wall of the first hole (1101) are both provided with threads. The first intermediate connecting part (102) has cylindrical holes at the upper and lower ends. The first intermediate connecting portion (102) has a protrusion, the middle portion of which is a second hollow (1205), a second hole (1201) is formed in the middle of the two protrusions, the inner wall of the second hole (1201), the outer wall (1202) of the upper protrusion, and the outer wall (1203) of the lower protrusion are all provided with threads, the first hole (1201) and the second hole (1201) are concentric and have the same inner diameter, the threads of the outer wall (1202) of the upper protrusion of the first intermediate connecting portion (102) match the threads in the first hollow (1102) of the medium pipe fixing portion (101), A third hole (1301) is formed inside the first electrode fixing portion (103), the inner wall of the third hole (1301) is provided with a thread and matches the thread of the outer wall (1203) protruding below the first intermediate connecting portion (102), a fourth hole (1302) is provided below the third hole (1301) which is concentric and has an inner diameter smaller than that of the third hole (1301), the threads of the first hole (1101) and the second hole (1201) match the threads of the cylindrical metal rod (601) in the inner electrode (6), and the outer sealing member (1302) is provided at the bottom of the third hole (1301). The inner diameters of the second hollow space (1205) and the fourth hole (1302) of the sealing fixture (1) match the outer diameter of the third cylindrical quartz tube (401) of the external medium tube (4); the inner diameters of the second hollow space (1205) and the fourth hole (1302) of the internal sealing fixture (2) match the outer diameter of the first cylindrical quartz tube (501) of the internal medium tube (5); and the second hollow space (1205) of the first intermediate connecting portion (102) of the external sealing fixture (1) is provided with a high-voltage electrode outlet hole (1204).

10. The plasma-coupled fluidized catalyst device according to claim 8, characterized in that: The bottom end sealing fixture (11) comprises a medium pipe connecting portion (111) and an air intake portion (112) located below the medium pipe connecting portion, the medium pipe connecting portion (111) has a third hollow space (11102) inside, an opening at the lower end, and a fifth hole (11101) at the upper portion, the inner wall of the third hollow space (11102) being provided with a thread, a cylindrical protrusion being provided at the upper end of the air intake portion (112), the outer wall (11201) of the cylindrical protrusion being provided with a thread matching the thread of the inner wall of the third hollow space (11102), and a sixth hole (11101) being concentric with the fifth hole (11101) and having the same inner diameter as the fifth hole (11101) being provided in the middle of the protrusion. 11202), an air inlet side port (11204) is provided on the side of the air inlet portion (112), a seventh hole (11203) is provided below the sixth hole (11202) and is concentric with the sixth hole (11202) and has an inner diameter smaller than that of the sixth hole (11202), the sixth hole (11202) and the seventh hole (11203) do not penetrate the air inlet portion (112), the aperture of the fifth hole (11101) matches the outer diameter of the fourth cylindrical quartz tube (403) in the outer medium tube (4), and the aperture of the seventh hole (11203) matches the outer diameter of the second cylindrical quartz tube (403) in the inner medium tube (5).

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