Photocatalytic carbon dioxide reduction reaction device

Abstract

The invention provides a photocatalytic carbon dioxide reduction reaction device, which relates to the technical field of photocatalytic reaction equipment.The photocatalytic carbon dioxide reduction reaction device comprises a reactor body, a microreactor, a gas inlet, a gas outlet, a gas distribution plate and a catalytic reaction frame, the catalytic reaction frame comprises an optical fiber lamp tube strip and a vortex generator, the vortex generator comprises a Venturi tube and a turbulent flow bluff body, and gas penetrating through the Venturi tube is blocked through the turbulent flow bluff body so that the Karman vortex street phenomenon can be generated. The contact area of gas and the catalytic wall plate is increased through the air holes formed in the catalytic wall plate, in addition, the Venturi tube and the turbulent flow bluff body are further arranged in the reaction channel, the turbulent flow bluff body is used for blocking the gas penetrating through the Venturi tube, so that a Karman vortex street phenomenon is generated, and the catalytic effect is improved. Furthermore, the gas forms vortex in the reaction channel, the boundary layer of the reaction gas is broken, and the efficiency of the photocatalytic reaction is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of photocatalytic reaction equipment, and particularly to a photocatalytic carbon dioxide reduction reaction device. Background Art

[0002] The massive consumption of fossil energy brings two severe problems to mankind: energy crisis and environmental problems. This has become a common challenge faced by the development of all countries in the world. It is generally believed that the excessive emission of CO2 is the main cause of a series of extreme environmental change problems such as global warming, land desertification, and ocean acidification. Therefore, the reduction of CO2 emissions has become an urgent problem that needs to be solved by all countries in the world.

[0003] The photocatalytic reduction of CO2 technology can reduce CO2 to fuels such as CH3OH and CH3CH2OH, which can not only reduce the concentration of CO2 in the atmosphere but also achieve the conversion and storage of energy. During the reaction process of photocatalytic reduction of CO2, the reactor, as the core device, its performance directly determines whether the reaction can proceed efficiently and stably. However, the existing photocatalytic reduction of CO2 reactors have many challenges in aspects such as light energy utilization rate, contact area between reactants and catalysts, mass transfer efficiency, and catalyst separation and recovery, which seriously affect the further development and industrial application of the photocatalytic reduction of CO2 technology.

[0004] In the prior art, there is a regular reticular porous carbide carrier suitable for catalysts and its preparation method, and a regular photocatalyst obtained by loading a photocatalyst on this carrier and its preparation method, with the publication number of "CN1836777A". The carbide carrier of this catalyst is a reticular porous carbide carrier, which can be directly prepared on a support, with firm adhesion, high mechanical strength and adsorption performance, fundamentally avoiding problems such as the carrier falling off from the support. The secondary loading of the carrier is carried out by coating, making it easy to control the thickness of the carbon layer of the carrier. Through carbonization and activation, the surface area and pore structure of the carbide carrier can be adjusted within a wide range, facilitating the manufacture of carriers suitable for different catalysts to adapt to different actual situations. The regular photocatalyst loaded on the carbide carrier is a photocatalyst that combines adsorption and reactivity, with the characteristics of high light flux and low pressure drop, and can be conveniently used for the treatment of gas-phase or liquid-phase pollution.

[0005] However, the above-mentioned device still has obvious defects during use: the pores set in the above-mentioned device are relatively dense, increasing the resistance to gas flow, thus affecting the reaction efficiency. In addition, in the prior art, there are also reactors with larger pore diameters, but the smooth flow of the gas stream will cause the reaction gas to form a boundary layer. The boundary layer of the reaction gas refers to a thin layer region with significant velocity gradient and concentration gradient formed near the solid surface in the reactor when the reaction gas contacts the surface of the solid catalyst or other solid boundaries, such as the reactor wall, due to the viscosity of the fluid and the hindrance of the solid surface. The existence of this gas boundary will increase the mass transfer resistance and further limit the reaction rate. Summary of the Invention

[0006] The purpose of the present invention is to provide a photocatalytic carbon dioxide reduction reaction device to solve the problems raised in the above-mentioned background technology.

[0007] To achieve the above purpose, the present invention provides the following technical solutions: A photocatalytic carbon dioxide reduction reaction device, comprising: A reactor body, which is composed of a base, a housing, and a top cover. The base, the housing, and the top cover enclose to form a reactor inner cavity; A microreactor, which is assembled by splicing a number of vertically stacked and staggered catalytic wall plates to form a number of reaction channels arranged in a rectangular array from bottom to top. The catalytic wall plates are coated with a photocatalyst; An air inlet and outlet, which includes a reaction gas inlet and a reaction product outlet. The reaction gas inlet is arranged below the housing, and the reaction product outlet is arranged above the housing. Both the reaction gas inlet and the reaction product outlet are communicated with the inside of the reactor cavity; A gas distribution plate, which is fixedly installed on the assembly groove opened in the housing. The gas distribution plate is provided with gas diffusion holes distributed in a rectangular array corresponding to the reaction channels one by one. The microreactor is fixedly installed above the gas distribution plate. The reaction gas inlet is arranged below the gas diffusion holes. The reaction gas enters the reactor inner cavity through the reaction gas inlet, passes through the gas diffusion holes opened on the gas distribution plate to form small airflows, and finally enters the reaction channels formed by the microreactor; The catalytic reaction rack is fixedly installed on the gas distribution plate in a rectangular array. The catalytic reaction racks are inserted into the reaction channels of the microreactors in a one-to-one correspondence. The catalytic reaction rack includes an optical fiber lamp tube strip and a vortex generator. There are no less than two groups of vortex generators, and the vortex generators are fixedly connected to the optical fiber lamp tube strip. The optical fiber lamp tube strip supports the vortex generators so that they are distributed at different heights in the reaction channels. The vortex generator includes a Venturi tube and a flow disturbance blunt body. The flow disturbance blunt body is fixedly installed at the gas outlet end of the Venturi tube. By blocking the gas passing through the Venturi tube with the flow disturbance blunt body, the Karman vortex street phenomenon is generated, thereby breaking the boundary layer of the reaction gas and improving the efficiency of the photocatalytic reaction.

[0008] Preferably, the catalytic wall plate is provided with air holes and splicing grooves. The air holes are one or a combination of more of triangle, quadrilateral, pentagon, hexagon, and circle. The three-dimensional connection channels for gas flow are formed inside the microreactor through the air holes.

[0009] Preferably, the reaction gas inlet is used to introduce carbon dioxide and water vapor required for the reaction, and the reaction product outlet is used to discharge the products generated by the reaction.

[0010] Preferably, a sampling port is further opened on the reactor body above the outer shell, and a gas sampling system is connected to the sampling port.

[0011] Preferably, the gas sampling system includes an external sampling tube, a gas box, a hollow pump, an exhaust pipe, and a magnetically controlled valve. The hollow pump is communicated with the gas box through a pipeline. Magnetically controlled valves are respectively installed on the pipe bodies at both ends of the gas box. The pipe bodies at both ends of the gas box are respectively communicated with the external sampling tube and the exhaust pipe through the magnetically controlled valves.

[0012] Preferably, an installation groove for inserting the catalytic wall plate of the microreactor is further provided inside the outer shell.

[0013] Preferably, there are two vortex generators. The Venturi tube is a hollow tube body structure with the smallest middle diameter and continuously increasing diameters on both sides. An airbag groove is further opened at the smallest diameter of the Venturi tube. A diameter adjustment film is arranged outside the airbag groove. By pumping air in and out of the airbag groove, the degree of expansion of the diameter adjustment film is adjusted, and then the diameter of the Venturi tube is adjusted.

[0014] Preferably, the airbag grooves opened on the Venturi tube are communicated with the pump suction pipes opened outside the outer shell through the air ducts opened on the Venturi tube and the optical fiber lamp tube strip. There is a pair of pump suction pipes, and the same pump suction pipe is used to synchronously adjust the diameters of several Venturi tubes arranged at the same height.

[0015] Preferably, regulating solenoid valves are provided on the pump suction pipes. The pump suction pipes are connected to a two-way air pump through a three-way pipe, and the diameter of the Venturi tube at the same height is correspondingly adjusted through the two-way air pump.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention adopts a stacked and spliced microreactor structure. The contact area between the gas and the catalytic wall plate is increased by the air holes provided on the catalytic wall plate. In addition, a Venturi tube and a flow disturbance blunt body are arranged in the reaction channel. The flow disturbance blunt body blocks the gas passing through the Venturi tube to generate a von Kármán vortex street phenomenon, so that the gas forms a vortex in the reaction channel, breaking the boundary layer of the reaction gas and improving the efficiency of the photocatalytic reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is an exploded schematic view of the overall structure of the present invention; Figure 2 is a partially enlarged cross-sectional schematic view of the catalytic reaction frame of the present invention; Figure 3 is a schematic view of the connection structure of the catalytic reaction frame of the present invention; Figure 4 is a horizontal cross-sectional schematic view of the outer shell of the present invention; Figure 5 is a schematic view of the overall structure of the microreactor of the present invention; Figure 6 is a schematic view of the overall structure of the present invention; Figure 7 is a schematic view of the catalytic wall plate structure of the present invention; Figure 8 is a schematic view of the installation positions of the reaction gas inlet and the reaction product outlet of the present invention.

[0018] In the figure: 1 reactor body, 2 base, 3 outer shell, 4 top cover, 5 microreactor, 6 catalytic wall plate, 7 reaction channel, 8 reaction gas inlet, 9 reaction product outlet, 10 gas distribution plate, 11 gas diffusion hole, 12 catalytic reaction frame, 13 optical fiber lamp strip, 14 eddy current generator, 15 Venturi tube, 16 flow disturbance blunt body, 17 air hole, 18 splicing groove, 19 sampling port, 20 external sampling pipe, 21 air box, 22 hollow pump, 23 exhaust pipe, 24 magnetic control valve, 25 installation groove, 26 airbag groove, 27 pipe diameter adjustment film, 28 pump suction pipe, 29 regulating solenoid valve, 30 three-way pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0020] Please refer to Figure 1-8 , the present invention provides a technical solution: Embodiment 1: A photocatalytic carbon dioxide reduction reaction device, comprising: A reactor body 1, which is composed of a base 2, a housing 3 and a top cover 4. The base 2, the housing 3 and the top cover 4 enclose to form a reactor inner cavity; A microreactor 5, which is formed by splicing and combining a plurality of catalytic wall plates 6 that are vertically stacked and staggered, and forms a plurality of reaction channels 7 arranged in a rectangular array from bottom to top. The catalytic wall plates 6 are coated with a photocatalyst; An air inlet and outlet, which includes a reaction gas inlet 8 and a reaction product outlet 9. The reaction gas inlet 8 is arranged below the housing 3, and the reaction product outlet 9 is arranged above the housing 3. Both the reaction gas inlet 8 and the reaction product outlet 9 are communicated with the inside of the reactor cavity; A gas distribution plate 10, which is fixedly installed on an assembly groove opened in the housing 3. The gas distribution plate 10 is provided with gas diffusion holes 11 that are arranged in a rectangular array corresponding to the reaction channels 7 one by one. The microreactor 5 is fixedly installed above the gas distribution plate 10. The reaction gas inlet 8 is arranged below the gas diffusion holes 11. The reaction gas enters the reactor inner cavity through the reaction gas inlet 8, passes through the gas diffusion holes 11 opened on the gas distribution plate 10 to form small airflows, and finally enters the reaction channels 7 formed by the microreactor 5; A catalytic reaction rack 12, which is fixedly installed on the gas distribution plate 10 in a rectangular array. The catalytic reaction rack 12 is inserted into the reaction channels 7 of the microreactor 5 in a one-to-one correspondence. The catalytic reaction rack 12 includes an optical fiber lamp strip 13 and a vortex generator 14. There are no less than two groups of vortex generators 14. The vortex generator 14 is fixedly connected to the optical fiber lamp strip 13, and the optical fiber lamp strip 13 is used to support the vortex generator 14 so that it is distributed at different heights in the reaction channels 7. The vortex generator 14 includes a Venturi tube 15 and a flow disturbing blunt body 16. The flow disturbing blunt body 16 is fixedly installed at the gas outlet end of the Venturi tube 15. The flow disturbing blunt body 16 blocks the gas passing through the Venturi tube 15 to generate a Karman vortex street phenomenon, thereby breaking the boundary layer of the reaction gas and improving the efficiency of the photocatalytic reaction.

[0021] In this embodiment, the reactor body 1 serves as the main structure of the reaction. It is composed of a base 2, a housing 3, and a top cover 4. The reactor inner cavity is formed by enclosing the base 2, the housing 3, and the top cover 4. The micro-reactor 5 is arranged in the reactor inner cavity. The micro-reactor 5 is assembled by splicing a number of vertically stacked and staggered catalytic wall plates 6 to form a three-dimensional gas flow channel. The catalytic wall plates 6 are coated with a photocatalyst. The gas generates a reaction by contacting the photocatalyst. An installation groove 25 for inserting the catalytic wall plates 6 of the micro-reactor 5 is also arranged in the housing 3, so that the micro-reactor 5 can be stably installed in the housing 3. The reaction gas in this embodiment is steam and carbon dioxide gas. The reaction gas inlet 8 is used to introduce the required carbon dioxide and water vapor for the reaction, and the reaction product outlet 9 is used to discharge the products generated by the reaction. Both the reaction gas inlet 8 and the reaction product outlet 9 are arranged on the housing 3. And air holes 17 and splicing grooves 18 are formed on the catalytic wall plates 6. The air holes 17 are regular polygon or circular opening structures, so that a three-dimensional connection channel for gas flow is formed inside the micro-reactor 5. The splicing grooves 18 are used for assembling the micro-reactor 5. The gas flows upward from the gas distribution plate 10 arranged at the bottom of the micro-reactor 5, and gas diffusion holes 11 are formed on the gas distribution plate 10. Refer to the attached instructions Figure 3 It can be seen that the gas diffusion holes 11 are located directly below each reaction channel. The reaction gas enters the reactor inner cavity through the reaction gas inlet 8, passes through the gas diffusion holes 11 formed on the gas distribution plate 10 to form small airflows, and finally enters the reaction channels 7 formed by the micro-reactor 5. In addition, a catalytic reaction rack 12 is inserted in the reaction channels 7, and a set of catalytic reaction racks 12 are arranged in each reaction channel 7. The catalytic reaction rack 12 includes a fiber optic lamp strip 13 and a vortex generator 14. The fiber optic lamp strip 13 is used to connect to an external circuit to provide sufficient light for the reaction. The fiber optic lamp strip 13 is formed by fixedly installing fiber optic lamp beads on a tube structure. At the same time, the fiber optic lamp strip 13 also serves as a support mechanism for the vortex generator 14. The vortex generator 14 includes a Venturi tube 15 and a flow disturbing blunt body 16. The Venturi tube 15 is a hollow tube structure with the smallest middle diameter and continuously increasing diameters on both sides. When the gas passes through the Venturi tube, the flow rate increases due to the decrease in diameter. Cooperating with the flow disturbing blunt body 16 arranged at the outlet end of the Venturi tube 15, the passing airflow forms a Karman vortex street. The Karman vortex street refers to an alternating arrangement of vortex columns formed downstream of an object when a fluid bypasses a blunt body, which is a classic phenomenon in fluid dynamics. By forming the Karman vortex street, the airflow passing through the Venturi tube 15 can form a vortex, thereby breaking the boundary layer of the reaction gas, and further playing a role in improving the photocatalytic reaction. The setting of this catalytic reaction rack enables the reaction airflow to form a stable vortex without introducing electrical components. And through the setting of no less than two groups of vortex generators, the gas flowing through the reaction channels 7 can fully contact the surface of the catalytic wall plates 6, thereby improving the reaction rate.

[0022] Example Two: A sampling port 19 is further opened on the reactor body 1 above the outer shell 3, and a gas sampling system is connected to the sampling port 19.

[0023] The gas sampling system includes an external sampling pipe 20, a gas box 21, a hollow pump 22, an exhaust pipe 23 and a magnetically controlled valve 24. The hollow pump 22 is communicated with the gas box 21 through a pipeline. Magnetically controlled valves 24 are respectively installed on the pipe bodies at both ends of the gas box 21, and the pipe bodies at both ends of the gas box 21 are respectively communicated with the external sampling pipe 20 and the exhaust pipe 23 through the magnetically controlled valves 24.

[0024] In this embodiment, a sampling port 19 is provided on the outer shell 3 and is communicated with the reactor body 1 through the sampling port 19. The structure of the reactor body 1 is fully disclosed. Through the setting of the magnetically controlled valves 24 on the pipe bodies at both ends of the gas box 21, the conduction of different path pipe bodies can be carried out, and the gas is introduced into the gas box 21 during the negative pressure extraction process of the hollow pump 22, so that the gas finally discharges from the exhaust pipe 23. Subsequently, the gas in the gas box 21 can be further recycled into the reactor inner cavity by connecting a gas recovery pipe to the gas box 21, so as to fully recycle the gas.

[0025] Example Three: Two eddy current generators 14 are provided. The venturi tube 15 is a hollow tube body structure with the smallest middle diameter and continuously increasing diameters on both sides. An airbag groove 26 is further opened at the smallest diameter of the venturi tube 15, and a diameter adjustment film 27 is arranged outside the airbag groove 26. The inflation degree of the diameter adjustment film 27 is adjusted by pumping air into and out of the airbag groove 26, and then the diameter of the venturi tube 15 is adjusted.

[0026] In this embodiment, further by opening an airbag groove 26 at the smallest diameter of the venturi tube 15 and arranging a diameter adjustment film 27 outside the airbag groove 26, the diameter can be adjusted by pumping air in and out. The significance of such a setting is that the size of the air flow passing through the venturi tube 15 can be adjusted, so as to adjust the eddy current rotation speed formed by the gas at the rear end of the bluff body, and then adjust the reaction rate.

[0027] Example Four: The airbag groove 26 opened on the venturi tube 15 is communicated with the pump extraction gas pipes 28 opened outside the outer shell 3 through the air ducts opened on the venturi tube 15 and the optical fiber lamp strip 13. A pair of pump extraction gas pipes 28 are provided, and the same pump extraction gas pipe 28 is used to synchronously adjust the diameters of a plurality of venturi tubes 15 arranged at the same height.

[0028] Regulating solenoid valves 29 are provided on the pump suction pipes 28. The pump suction pipes 28 are connected to the two-way air pump through the three-way pipe 30, and the diameter of the Venturi tube 15 at the same height is correspondingly adjusted by the two-way air pump.

[0029] In this embodiment, the adjustment method of the diameter adjustment film 27 is further disclosed. Refer to the attached drawings of the specification Figure 2 and 3 , each Venturi tube 15 is supported by four optical fiber lamp strip 13 arranged at the corners. Two of the optical fiber lamp strip 13 are of hollow structure, and the air channels arranged inside are respectively communicated with the airbag grooves 26 in the Venturi tubes 15 at different heights. The air channels inside the optical fiber lamp strip 13 are communicated with the two-way air pump through the pump suction pipe 28. The air pump is not shown in the figure. The two-way air pump pumps air into the three-way pipe 30, and the corresponding regulating solenoid valve 29 is opened as required, so that the gas enters the corresponding optical fiber lamp strip 13 and finally enters the airbag groove 26 of the Venturi tube 15 at the corresponding height, thereby synchronously adjusting the inner diameter of the Venturi tube 15 at the same height.

[0030] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A photocatalytic carbon dioxide reduction reaction device, characterized in that, Comprising: A reactor body, which is composed of a base, a housing, and a top cover. The base, the housing, and the top cover enclose to form a reactor inner cavity; A micro-reactor, which is formed by splicing and combining a number of vertically stacked and staggered catalytic wall plates, and forms a number of reaction channels arranged in a rectangular array and extending from bottom to top. The catalytic wall plates are coated with a photocatalyst; An air inlet and outlet, which includes a reaction gas inlet and a reaction product outlet. The reaction gas inlet is arranged below the housing, and the reaction product outlet is arranged above the housing. Both the reaction gas inlet and the reaction product outlet are communicated with the inside of the reactor cavity; A gas distribution plate, which is fixedly installed on an assembly groove opened in the housing. The gas distribution plate is provided with gas diffusion holes corresponding to the reaction channels one by one and arranged in a rectangular array. The micro-reactor is fixedly installed above the gas distribution plate. The reaction gas inlet is arranged below the gas diffusion holes. The reaction gas enters the reactor inner cavity through the reaction gas inlet, passes through the gas diffusion holes opened on the gas distribution plate to form small airflows, and finally enters the reaction channels formed by the micro-reactor; A catalytic reaction rack, which is fixedly installed on the gas distribution plate in a rectangular array. The catalytic reaction rack is inserted into the reaction channels of the micro-reactor one by one. The catalytic reaction rack includes an optical fiber lamp strip and a vortex generator. There are no less than two groups of vortex generators. The vortex generator is fixedly connected to the optical fiber lamp strip, and the optical fiber lamp strip supports the vortex generator so that it is distributed at different heights in the reaction channels. The vortex generator includes a Venturi tube and a flow disturbance blunt body. The flow disturbance blunt body is fixedly installed at the gas outlet end of the Venturi tube. By blocking the gas passing through the Venturi tube with the flow disturbance blunt body, the Karman vortex street phenomenon is generated, thereby breaking the boundary layer of the reaction gas and improving the efficiency of the photocatalytic reaction.

2. The photocatalytic carbon dioxide reduction reaction device according to claim 1, wherein: The catalytic wall plates are provided with air holes and splicing grooves. The air holes are one or a combination of a triangle, a quadrilateral, a pentagon, a hexagon, and a circle. Three-dimensional connection channels for gas flow are formed inside the micro-reactor through the air holes.

3. The photocatalytic carbon dioxide reduction reaction device according to claim 1, characterized in that: The reaction gas inlet is used to introduce carbon dioxide and water vapor required for the reaction, and the reaction product outlet is used to discharge the products generated by the reaction.

4. A photocatalytic carbon dioxide reduction reaction device according to claim 1, characterized in that: A sampling port is also opened on the reactor body above the housing, and a gas sampling system is connected to the sampling port.

5. A photocatalytic carbon dioxide reduction reaction device according to claim 4, characterized in that: The gas sampling system includes an external sampling tube, a gas box, a hollow pump, an exhaust pipe, and a magnetically controlled valve. The hollow pump is communicated with the gas box through a pipeline. Magnetically controlled valves are respectively installed on the pipe bodies at both ends of the gas box. The pipe bodies at both ends of the gas box are respectively communicated with the external sampling tube and the exhaust pipe through the magnetically controlled valves.

6. The photocatalytic carbon dioxide reduction reaction device according to claim 1, characterized in that: An installation groove for inserting the catalytic wall plates of the micro-reactor is also arranged inside the housing.

7. The photocatalytic carbon dioxide reduction reaction device according to claim 1, characterized in that: There are two eddy current generators provided. The venturi tube is a hollow tube structure with the smallest diameter in the middle and continuously increasing diameters on both sides. An airbag groove is also opened at the smallest diameter of the venturi tube, and a diameter adjustment film is arranged outside the airbag groove. By pumping air into and out of the airbag groove, the expansion degree of the diameter adjustment film is adjusted, and then the diameter size of the venturi tube is adjusted.

8. The photocatalytic carbon dioxide reduction reaction device according to claim 7, characterized in that: The airbag groove opened on the venturi tube is communicated with the air pump tube opened outside the shell through the air ducts opened on the venturi tube and the optical fiber lamp strip. There are a pair of air pump tubes, and the same air pump tube is used to synchronously adjust the diameters of several venturi tubes arranged at the same height.

9. The photocatalytic carbon dioxide reduction reaction device according to claim 8, characterized in that: Regulating solenoid valves are opened on both air pump tubes. The air pump tubes are connected to a two-way air pump through a three-way pipe, and the diameters of the venturi tubes at the same height are correspondingly adjusted through the two-way air pump.

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