Solar photothermal catalytic continuous hydrogen production system

Abstract

This invention discloses a solar-thermal catalytic continuous hydrogen production system, comprising a photothermal conversion preheating section and a catalytic hydrogen production reaction section. The photothermal conversion preheating section includes a photothermal conversion tube and a preheating concentrator. The preheating concentrator focuses sunlight to heat the hydrogen production reactants within the photothermal conversion tube. The photothermal conversion preheating section also includes a heat storage device to store excess heat. The catalytic hydrogen production reaction section is connected to the photothermal conversion tube. The heated hydrogen production reactants are transported to the catalytic hydrogen production reaction section for catalytic reaction. The catalytic hydrogen production reaction section has multiple reaction sub-modules connected in parallel. This solar-thermal catalytic continuous hydrogen production system can achieve continuous hydrogen production around the clock through solar-thermal catalysis, unaffected by the intermittency and uneven distribution of solar energy, thus improving solar energy utilization. By designing the reaction section as multiple reaction sub-modules to jointly complete the continuous hydrogen production reaction, it improves catalyst utilization and reduces hydrogen production costs.

Description

Technical Field

[0001] This invention relates to the field of renewable energy utilization technology, and specifically to a solar photothermal catalytic continuous hydrogen production system. Background Technology

[0002] Earth possesses abundant solar energy resources, characterized by their wide distribution, ease of development, and environmental friendliness. Current utilization of solar energy includes concentrated solar power (CSP) and photovoltaic power generation. Directly converting solar energy into chemical energy through chemical conversion methods is a relatively new approach, including photocatalysis and photothermal catalysis. However, simple photocatalysis can only absorb and utilize high-energy photons in the solar spectrum, thus absorbing only about 50% of the photons in the solar spectrum, resulting in an energy conversion efficiency of less than 3%, which significantly limits its application. Approximately 50% of the low-energy photons in the solar spectrum can be directly converted into heat. The increased temperature can enhance the performance of photocatalysis, and at suitable temperatures, thermocatalytic hydrogen production can be achieved. The coupling of photocatalytic and thermocatalytic hydrogen production can improve the utilization of solar energy.

[0003] However, due to factors such as catalyst efficiency, low solar energy density, and discontinuous solar energy, current solar hydrogen production systems have low yields and cannot be utilized at suitable system sizes (e.g., a total area of ​​15m²). 2 The following) reach 100m 3 The low daily hydrogen production rate significantly limits the commercial application of solar-powered hydrogen production systems. Furthermore, existing solar-powered hydrogen production systems (such as CN116639649A and CN116358171A) cannot operate continuously around the clock due to weather conditions, further limiting hydrogen production. Moreover, achieving higher hydrogen production rates typically requires operating temperatures exceeding 250°C, necessitating sophisticated concentrators. Without proper system design, reaching this reaction temperature can be difficult, or significant equipment investment is required to meet the reaction demands, greatly increasing hydrogen production costs. Summary of the Invention

[0004] Therefore, it is necessary to provide a solar photothermal catalytic continuous hydrogen production system to address the problems of low utilization rate of existing solar hydrogen production, low catalyst utilization rate, and high hydrogen production cost.

[0005] A solar photothermal catalytic continuous hydrogen production system includes:

[0006] The photothermal conversion preheating section includes a photothermal conversion tube and a preheating concentrating component. The preheating concentrating component focuses sunlight to heat the hydrogen-producing reactants inside the photothermal conversion tube. The photothermal conversion preheating section is also equipped with a heat storage device to store excess heat.

[0007] The catalytic hydrogen production reaction section is connected to the photothermal conversion tube. The heated hydrogen production reactants are transported to the catalytic hydrogen production reaction section for catalytic reaction. The catalytic hydrogen production reaction section is provided with multiple reaction sub-modules, and the multiple reaction sub-modules are connected in parallel.

[0008] The aforementioned solar-thermal catalytic continuous hydrogen production system focuses sunlight through a preheating concentrator to heat the hydrogen-producing reactants within the photothermal conversion tube to a suitable reaction temperature (greater than 250°C). The heated reactants are then transported to the catalytic hydrogen production reaction section for catalytic reaction. Excess heat is stored in a thermal storage device, which continuously preheats the reactants to the appropriate reaction temperature, maintaining the stable operation of the photothermal catalytic hydrogen production reaction. This system enables continuous, all-weather hydrogen production through solar-thermal catalytic coupling, unaffected by the intermittency and uneven distribution of solar energy, thus improving solar energy utilization. Since the catalytic hydrogen production reaction is completed within a short distance, to improve catalyst utilization, the reaction section is designed as multiple reaction sub-modules connected in parallel to continuously complete the hydrogen production reaction, reducing hydrogen production costs.

[0009] In one embodiment, the catalytic hydrogen production reaction section includes a catalytic reaction pipeline and a circulation pipeline. Multiple reaction sub-modules are sequentially spaced along the axial direction of the catalytic reaction pipeline, and the multiple reaction sub-modules are connected in parallel through the circulation pipeline.

[0010] In one embodiment, the reaction submodule includes a catalyst section and a product diffusion section without a catalyst, wherein the product generated by the catalytic reaction of the hydrogen-producing reactants in the catalyst section is discharged through the product diffusion section.

[0011] In one embodiment, the inner diameter of the product diffusion section increases in the direction away from the catalyst section, forming an angle with the catalyst section.

[0012] In one embodiment, the reaction submodule includes a first reaction pipe, a second reaction pipe and a third reaction pipe nested in sequence. The first reaction pipe is filled with a thermocatalytic hydrogen production catalyst, and the space between the first reaction pipe and the second reaction pipe is filled with a photothermal catalytic hydrogen production catalyst. The outer wall of the second pipe is provided with a photothermal catalytic hydrogen production catalyst with photothermal conversion characteristics.

[0013] In one embodiment, a reaction concentrator is provided outside the catalytic reaction pipeline to heat the hydrogen-producing reactants.

[0014] In one embodiment, the photothermal conversion preheating section further includes a heat storage circulation pipe, the heat storage device is installed on the heat storage circulation pipe, and the heat storage carrier in the photothermal conversion tube is circulated and heated through the heat storage circulation pipe.

[0015] In one embodiment, the photothermal conversion tube includes a heat-conducting pipe, an intermediate pipe, and a transparent pipe arranged sequentially from the inside to the outside. The heat-conducting pipe is used to flow the heat storage carrier, and the space between the heat-conducting pipe and the intermediate pipe is used to flow the hydrogen production reactants. The transparent pipe and the intermediate pipe are kept under vacuum to achieve heat insulation.

[0016] In one embodiment, the outer surface of the intermediate pipe is loaded with a photothermal conversion material.

[0017] In one embodiment, the outer surface of the heat-conducting pipe is provided with a heat-conducting enhanced microstructure. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0019] Figure 1 This is a schematic diagram of the structure of a solar photothermal catalytic continuous hydrogen production system in one embodiment;

[0020] Figure 2 Figure 1 Schematic diagram of the preheating section for photothermal conversion;

[0021] Figure 3 Figure 2 Cross-sectional view of the photothermal conversion tube;

[0022] Figure 4 for Figure 3 A schematic diagram of thermally enhanced microstructures on the outer surface of a heat-conducting pipe;

[0023] Figure 5 for Figure 1 Schematic diagram of the structure of the catalytic hydrogen production reaction section;

[0024] Figure 6 This is a schematic diagram of the structure of the two reaction submodules;

[0025] Figure 7 for Figure 6 Cross-sectional view of the intermediate reaction submodule;

[0026] Figure 8 for Figure 7 A schematic diagram showing the triangular pore structure within a mesothermal catalytic hydrogen production catalyst;

[0027] Figure 9 for Figure 7 A schematic diagram of a circular pore structure within a mesothermal catalytic hydrogen production catalyst.

[0028] Figure 10 for Figure 7 A schematic diagram of the internal pore structure of a mesothermal catalytic hydrogen production catalyst, which is a mesh-like interstitial structure.

[0029] Figure label:

[0030] 1-Sunlight, 10-Photothermal conversion preheating section, 11-Photothermal conversion tube, 111-Heat conduction pipe, 112-Intermediate pipe, 113-Transparent pipe, 114-Heat storage carrier flow area, 115-Reactant flow area, 116-Vacuum pipe area, 117-Thermal conductivity enhanced microstructure, 118-Photothermal conversion material, 12-Preheating concentrating component, 13-Heat storage device, 14-Heat storage circulation pipe, 15-Preheating system support component, 20-Catalytic hydrogen production reaction section, 21-Catalytic reaction pipe, 211-First reaction pipe, 212-Second reaction pipe, 213 - Third reaction pipeline, 214-Thermocatalytic hydrogen production catalyst, 215-Photothermal catalytic hydrogen production catalyst, 216-Photothermal catalytic hydrogen production catalyst with photothermal conversion characteristics, 214a-Porous structure, 217-Catalyst section, 218-Product diffusion section, 219-Angle, 22-Circulation pipeline, 221-Main circulation pipeline, 222-Internal circulation pipeline, 23-Reaction submodule, 24-Reaction focusing component, 25-Reaction system support component, 26-Hydrogen outlet, 262-Hydrogen separation membrane, 27-Collection pipeline, 28-Hydrogen production reactant inlet, 282-One-way valve. 29-Vacuum-water separation membrane, 30-Hydrogen production reactant vapor, 31-Post-reaction mixture, 40-Hydrogen purification device. Detailed Implementation

[0031] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the invention; therefore, the invention is not limited to the specific embodiments disclosed below.

[0032] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0034] Common photocatalytic-thermal catalytic coupled hydrogen production systems operate at reaction temperatures exceeding 250°C, and photothermal hydrogen production catalysts exhibit low performance at low temperatures. To improve catalyst utilization and solar energy utilization, such as... Figure 1 As shown, the present invention provides a solar photothermal catalytic continuous hydrogen production system, which mainly includes a photothermal conversion preheating section 10 and a catalytic hydrogen production reaction section 20.

[0035] Please refer to the following: Figure 2 The photothermal conversion preheating section 10 includes a photothermal conversion tube 11 and a preheating concentrating component 12. The photothermal conversion tube 11 is arranged laterally, and the preheating concentrating component 12 is located outside the photothermal conversion tube 11. The preheating concentrating component 12 focuses sunlight 1 to heat the hydrogen-producing reactants inside the photothermal conversion tube 11. The photothermal conversion preheating section 10 is also provided with a heat storage device 13 for storing excess heat. In one embodiment, the photothermal conversion preheating section 10 further includes a heat storage circulation pipe 14. The heat storage device 13 is installed on the heat storage circulation pipe 14, and the heat storage carrier inside the photothermal conversion tube 11 is circulated and heated through the heat storage circulation pipe 14.

[0036] In this process, the hydrogen-producing reactants are supplied to the photothermal conversion tube 11. The preheating concentrator 12 focuses sunlight 1 to heat the hydrogen-producing reactants inside the photothermal conversion tube 11, preheating them to a suitable reaction temperature (greater than 250°C), and storing excess heat in the heat storage device 13. The hydrogen-producing reactants, heated into steam, are transported through a pipeline outlet to the catalytic hydrogen production reaction section 20 for catalytic reaction. The heat storage carrier inside the photothermal conversion tube 11 is circulated and heated through a circulation pipe 22. The heat storage device 13 continuously preheats the hydrogen-producing reactants to a suitable reaction temperature, maintaining the stable progress of the photothermal catalytic hydrogen production reaction.

[0037] In the absence of sunlight, the thermal storage device 13 preheats the hydrogen-producing reactants to a suitable reaction temperature. The preheated reactants then continue the hydrogen-producing reaction in the reaction section, achieving a conversion rate of up to 50%. Combined with industrial waste heat utilization, this can reach a conversion rate of 40m³. 3 / day hydrogen production rate.

[0038] In one embodiment, the photothermal conversion preheating section 10 further includes a preheating system support component 15, on which the photothermal conversion tube 11 is mounted to maintain a horizontally positioned arrangement.

[0039] In one embodiment, the hydrogen production reactants can be pure water, a mixed solution of organic matter and water, or pure organic matter, etc., which can be specifically selected according to actual needs. Further, if a mixed solution of organic matter and water is selected, the mass ratio of the mixed solution of organic matter and water is 0.1 to 10, preferably 1 to 5.

[0040] In one embodiment, sunlight 1 can be either continuous or discontinuous. Continuous sunlight 1 is preferred. Due to the non-uniformity of sunlight 1, the concentration ratio of the preheating concentrator 12 can be reasonably adjusted to achieve optimal light intensity and temperature for photothermal catalytic hydrogen production. The adjustable range of the concentration ratio of the preheating concentrator 12 is 1 to 50. Preferably, to consider suitable photothermal catalytic performance, a concentration ratio of 5 to 15 is suitable.

[0041] In one embodiment, considering the variations in the incident angle of sunlight 1 in actual environments, the system provided by this invention is equipped with a light-tracking system to track these variations. The specific structure of the light-tracking system adopts existing light-tracking systems and will not be detailed here.

[0042] In one embodiment, the heating temperature can be between 50°C and 300°C, depending on the type of photothermal catalytic hydrogen production. Preferably, it is between 240°C and 280°C.

[0043] Please refer to the following: Figure 3 In one embodiment, the photothermal conversion tube 11 includes a heat-conducting pipe 111, an intermediate pipe 112, and a transparent pipe 113 arranged sequentially from the inside to the outside. The heat-conducting pipe 111 forms a heat storage carrier flow region 114, and the intermediate pipe 112 and the heat-conducting pipe 111 form a reactant flow region 115. The transparent pipe 113 allows sunlight 1 to enter the intermediate pipe 112, and the transparent pipe 113 and the intermediate pipe 112 form a vacuum pipe region 116 for achieving heat insulation.

[0044] In one embodiment, the heat-conducting pipe 111 is arranged as a pipe with good thermal conductivity. Specifically, the heat-conducting pipe 111 can be made of copper, aluminum or steel pipe with good thermal conductivity, and the heat-conducting pipe 111 contains a heat storage medium, such as heat transfer oil.

[0045] In one embodiment, the area between the heat-conducting pipe 111 and the intermediate pipe 112 is primarily used for the flow of reactants. Considering the requirements of low energy density sunlight 1 and high photothermal hydrogen production temperature, the inner diameter of the heat-conducting pipe 111 is preferably 25–35 mm, more preferably 30–32 mm. Considering good thermal conductivity and mechanical strength, the wall thickness of the heat-conducting pipe 111 is preferably 2–5 mm, more preferably 2–3 mm.

[0046] Please refer to the following: Figure 4 In one embodiment, a thermally enhanced microstructure 117 may be provided on the outer surface of the heat-conducting pipe 111 to enhance heat transfer. Specifically, the thermally enhanced microstructure 117 may be a micro-protrusion provided on the outer surface of the heat-conducting pipe 111.

[0047] In one embodiment, the heat conduction pipe 111 can cool or heat the hydrogen production reactants according to the needs of the actual operation process, so that the temperature of the reactants is between 240°C and 280°C.

[0048] In one embodiment, to achieve good photothermal conversion, a photothermal conversion material 118 is loaded on the surface of the intermediate pipe 112. Specifically, the preferred photothermal conversion material 118 is a black or dark-colored material, but other photothermal conversion materials 118 can also be used, combined with the preheating focusing component 12 to raise the temperature of the reaction solution to achieve the same system operation effect.

[0049] Based on the above embodiments, and further considering the size effect, the particle size of the photothermal conversion material 118 used in this invention is preferably less than 100 nm. Of course, a photothermal conversion material 118 with a size greater than 100 nm can also be used.

[0050] In one embodiment, considering the full utilization of the photothermal conversion material and the efficient conversion of solar energy, the thickness of the photothermal conversion material 118 is preferably 0.1–2 mm, more preferably 0.5–1 mm. Furthermore, the photothermal conversion material 118 can be loaded onto the intermediate conduit by methods such as chemical vapor deposition, vacuum ion plating and vacuum sputtering, electrochemical methods, liquid phase growth, coating, diffusion, and coating. Preferably, for common cylindrical heat collection tubes, the present invention recommends using commonly used DC magnetron sputtering technology for coating.

[0051] In one embodiment, a selective absorption film may be provided on the inner surface of the heat conduction pipe 111 to reduce solar energy reflection. The inner diameter of the heat conduction pipe 111 is preferably 45-55 mm, and more preferably 50-52 mm.

[0052] In one embodiment, the transparent pipe 113 may be a transparent quartz glass tube. Furthermore, the area between the intermediate pipe 112 and the transparent pipe 113 is kept in a vacuum state for heat insulation. Preferably, to improve the utilization rate of sunlight 1 and reduce reflection, the inner diameter of the transparent pipe 113 is preferably 80-90 mm. More preferably, it is 85-88 mm.

[0053] In one embodiment, considering good mechanical strength and thermal insulation effect, the wall thickness of the transparent pipe 113 is preferably 2 to 5 mm, and more preferably 2 to 3 mm.

[0054] In one embodiment, the heating process of the present invention can be natural heating generated by the photothermal conversion of sunlight 1, industrial waste heat utilization, or heat from the heat storage device 13. Furthermore, the heat storage device 13 can provide heat, enabling heating during periods without sunlight 1, and achieving all-weather photothermal catalytic hydrogen production.

[0055] Please refer to the following: Figure 5 and Figure 6 The catalytic hydrogen production reaction section 20 is connected to the photothermal conversion tube 11. The heated hydrogen production reactants are transported to the catalytic hydrogen production reaction section 20 for catalytic reaction. The catalytic hydrogen production reaction section 20 is provided with multiple reaction sub-modules 23, which are connected in parallel.

[0056] Among them, the actual photothermal catalytic hydrogen production rate that this invention aims to achieve is 100m³. 3 The catalyst arrangement length is approximately 4m per day, based on preliminary calculations. However, the photothermal catalytic hydrogen production reaction rate is relatively fast, meaning the reactant vapor will react completely within a 0.1m radius of the catalyst tube bundle. Therefore, if the reactants only enter from one section, a large portion of the catalyst will be essentially unused, significantly reducing catalyst utilization efficiency, decreasing the hydrogen production rate, and greatly increasing the cost of hydrogen production. To address the problem of low catalyst utilization efficiency, this invention innovatively proposes a segmented multi-module catalytic reaction, where each reaction sub-module 23 is connected in parallel.

[0057] In one embodiment, the catalytic hydrogen production reaction section 20 includes a catalytic reaction pipeline 21 and a circulation pipeline 22. Multiple reaction sub-modules 23 are sequentially spaced along the axial direction within the catalytic reaction pipeline 21, and these sub-modules are connected in parallel via the circulation pipeline 22. Specifically, the circulation pipeline 22 includes a main circulation pipeline 221 and an inner circulation pipeline 222. The main circulation pipeline 221 connects to the inlet and outlet of the catalytic reaction pipeline 21. The number of inner circulation pipelines 222 is the same as the number of reaction sub-modules 23. The inner circulation pipelines 222 connect the main circulation pipeline 221 and the corresponding reaction sub-modules 23 to supply reactant vapor to each reaction sub-module 23.

[0058] In one embodiment, the catalytic hydrogen production reaction section 20 further includes a reaction focusing component 24, which is disposed outside the catalytic reaction conduit 21. The reaction focusing component 24 is used to focus sunlight 1 to further heat the hydrogen production reactants and initiate the catalytic hydrogen production reaction. The catalytic hydrogen production reaction section 20 includes a reaction system support component 25, on which the catalytic reaction conduit 21 is mounted to maintain the catalytic reaction conduit 21 in a horizontally horizontal configuration.

[0059] Please refer to the following: Figure 7In one embodiment, the reaction submodule 23 includes a first reaction pipe 211, a second reaction pipe 212, and a third reaction pipe 213 arranged sequentially. The first reaction pipe 211 is filled with a thermocatalytic hydrogen production catalyst 214, and the space between the first reaction pipe 211 and the second reaction pipe 212 is filled with a photothermal catalytic hydrogen production catalyst 215. The outer wall of the second pipe is provided with a photothermal catalytic hydrogen production catalyst 216 with photothermal conversion characteristics. The third reaction pipe 213 is kept under vacuum for heat insulation.

[0060] In one embodiment, the diameters and wall thicknesses of the first reaction pipe 211, the second reaction pipe 212, and the third reaction pipe 213, as well as the arrangement of the photothermal catalytic hydrogen production catalyst 216 with photothermal conversion characteristics, are the same as those of the photothermal conversion preheating section 10.

[0061] In one embodiment, the thermocatalytic hydrogen production catalyst 214 can be selected as Cu-Al-SS. The preferred photothermal catalytic hydrogen production catalyst 215 of the present invention includes g-C3N4, TiO2, MXenes, SrTiO3, GaN, ZnO, and In2O. 3-x Bi2O 3-x The preferred photothermal catalytic hydrogen production catalyst 216 of this invention, which has photothermal conversion characteristics, includes PPCN, MXenes, GaN, and In2O. 3-x Bi2O 3-x wait.

[0062] In one embodiment, the present invention may also use multiple composite catalysts, in which some catalysts perform photocatalysis, some perform thermal catalysis, some perform endothermic action, and some perform catalytic promotion, etc. Furthermore, considering the size effect, the particle size of the photothermal conversion material 118 used in the present invention is preferably below 100 nm, although catalysts with a size greater than 100 nm can also be used.

[0063] In one embodiment, since the photothermal catalytic hydrogen production reaction is prone to reverse reaction, in order to expel the generated hydrogen gas as soon as possible, the reaction submodule 23 includes a catalyst section 217 and a product diffusion section 218 without catalyst. The hydrogen gas generated by the catalytic reaction of the hydrogen production reactants in the catalyst section 217 is quickly discharged through the product diffusion section 218 to minimize the occurrence of side reactions.

[0064] In one embodiment, the length L1 of the catalyst section 217 is preferably 0.05 to 0.15 m, more preferably 0.08 to 0.12 m. The length L2 of the product diffusion section 218 is preferably 0.01 to 0.03 m, more preferably 0.015 to 0.025 m.

[0065] In one embodiment, the inner diameter of the product diffusion section 218 increases in the direction away from the catalyst section 217, forming an angle 219 with the catalyst section 217. The product diffusion section 218 gradually expands along the hydrogen flow direction, which allows the hydrogen to be discharged quickly. Specifically, the angle 219β between the inner wall of the product diffusion section 218 and the inner wall of the catalyst section 217 is preferably 10° to 50°, and more preferably 25° to 35°.

[0066] In one embodiment, the sidewall of the catalytic reaction pipeline 21 is provided with a hydrogen outlet 26, and a hydrogen separation membrane 262 is installed on the hydrogen outlet 26 to separate the hydrogen in the catalytic reaction products from other products, allowing only hydrogen to be discharged through the hydrogen outlet 26. The catalytic reaction pipeline 21 may also include a collection pipeline 27 for collecting the hydrogen generated by each reaction submodule 23.

[0067] In one embodiment, the side wall of the catalytic reaction pipeline 21 is further provided with a hydrogen production reactant inlet 28, through which the hydrogen production reactant vapor 30 in the internal circulation pipeline 222 enters the reaction submodule 23. The hydrogen production reactant inlet 28 and the hydrogen outlet 26 are located on the upper and lower sides of the catalytic reaction pipeline 21, respectively, to avoid mutual interference between them. Furthermore, the hydrogen production reactant inlet 28 is provided with a one-way valve 282 to prevent the hydrogen production reactant vapor 30 entering the reaction submodule 23 from flowing back.

[0068] In one embodiment, a gas-liquid separation membrane 29 is provided between adjacent reaction submodules 23. The gas-liquid separation membrane 29 can isolate the gas between two adjacent reaction submodules 23, preventing hydrogen in the post-reaction mixture 31 from entering the next reaction submodule 23 and causing a reverse reaction. At the same time, the gas-liquid separation membrane 29 allows the hydrogen-producing reactants in the post-reaction mixture 31 to enter the next reaction submodule 23, where they undergo a catalytic reaction to produce hydrogen under the action of a catalyst.

[0069] Please see Figures 8 to 10 In one embodiment, densely packed catalyst increases the flow resistance of reactants and products, which is detrimental to the rapid occurrence of the reaction and the timely discharge of products, reducing catalyst utilization and increasing the probability of side reactions. Therefore, the thermocatalytic hydrogen production catalyst 214 is provided with a pore structure 214a extending axially along the catalytic reaction channel 21, which facilitates the flow of reactants and products. Specifically, the pore structure 214a can be triangular, circular, or mesh-like.

[0070] In one embodiment, the catalytic hydrogen production reaction section 20 further includes a hydrogen purification device 40, which is connected to the catalytic reaction pipeline 21. The hydrogen purification device 40 can purify the hydrogen to a high purity and then transport it to the subsequent application interface through the outlet. Specifically, the hydrogen purification device 40 is connected to the collection pipeline 27.

[0071] The working process of the above-mentioned solar photothermal catalytic continuous hydrogen production system is as follows:

[0072] The hydrogen-producing reactants are supplied to the photothermal conversion tube 11, where they are heated by focused sunlight 1. The heated reactants, now vaporized, are transported through a pipe outlet to the catalytic hydrogen production reaction section 20 for catalytic reaction. The heat storage carrier within the photothermal conversion tube 11 is circulated and heated through a heat storage circulation pipe 14, storing the heat in a heat storage device 13. The heat storage device 13 continuously preheats the hydrogen-producing reactants to a suitable reaction temperature, maintaining the stable progress of the photothermal catalytic hydrogen production reaction.

[0073] In the catalytic hydrogen production reaction section 20, the hydrogen-producing reactant vapor 30 enters the catalytic reaction pipe 21, where the hydrogen-producing reactant is further heated by the reaction focusing component 24 to maintain the energy requirements of the hydrogen production reaction. The reactants are supplied to each reaction submodule 23 through the circulation pipe 22. The hydrogen-producing reactants are catalyzed by the thermal catalytic hydrogen production catalyst 214, the photothermal catalytic hydrogen production catalyst 215, and the photothermal catalytic hydrogen production catalyst 216 with photothermal conversion characteristics, respectively, to produce hydrogen gas, which is discharged from the hydrogen outlet 26 through the product diffusion section 218.

[0074] The hydrogen discharged from each reaction submodule 23 is collected by the collection pipeline 27, purified to high purity by the hydrogen purification device 40, and then transported to the subsequent application interface through the outlet.

[0075] The aforementioned solar-thermal catalytic continuous hydrogen production system can achieve all-weather hydrogen production, operating continuously even on nights without sunlight, and is not limited by the intermittency or uneven distribution of solar energy. This system can be used in systems with a total area of ​​less than 15m². 2 Reaching 180m 3 The system achieves a hydrogen production rate of / day. It enables thermocatalytic hydrogen production under no-light conditions, with a conversion rate of up to 50%. It can raise the photothermal catalytic hydrogen production temperature to over 250°C without additional heating, reducing energy consumption. This invention allows for multi-modal assembly and operation, and with the designed product diffusion section 218, it significantly improves catalyst utilization and reduces side reactions, achieving a solar energy utilization rate of 25% and a conversion rate of up to 95%. Since the catalytic hydrogen production reaction is completed within a short distance, to improve catalyst utilization, the reaction section is designed as multiple reaction sub-modules 23, connected in parallel to continuously complete the hydrogen production reaction, thus reducing hydrogen production costs.

[0076] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A solar photothermal catalytic continuous hydrogen production system, characterized in that, include: The photothermal conversion preheating section includes a photothermal conversion tube and a preheating concentrating component. The preheating concentrating component focuses sunlight to heat the hydrogen production reactants in the photothermal conversion tube. The photothermal conversion preheating section is also equipped with a heat storage device to store excess heat. and A catalytic hydrogen production reaction section is connected to the photothermal conversion tube. The heated hydrogen production reactants are transported to the catalytic hydrogen production reaction section for catalytic reaction. The catalytic hydrogen production reaction section is provided with multiple reaction sub-modules, and the multiple reaction sub-modules are connected in parallel. The catalytic hydrogen production reaction section includes a catalytic reaction pipeline and a circulation pipeline. Multiple reaction sub-modules are sequentially spaced along the axial direction of the catalytic reaction pipeline, and the multiple reaction sub-modules are connected in parallel through the circulation pipeline. The reaction submodule includes a catalyst section and a product diffusion section without a catalyst. The products generated by the catalytic reaction of the hydrogen-producing reactants in the catalyst section are discharged through the product diffusion section. A gas-liquid separation membrane is provided between adjacent reaction sub-modules. The gas-liquid separation membrane isolates the gas between two adjacent reaction sub-modules and allows the hydrogen-producing reactants in the reaction mixture to enter the next reaction sub-module.

2. The solar photothermal catalytic continuous hydrogen production system according to claim 1, characterized in that, The inner diameter of the product diffusion section increases in the direction away from the catalyst section, forming an angle with the catalyst section.

3. The solar photothermal catalytic continuous hydrogen production system according to claim 1, characterized in that, The reaction submodule includes a first reaction pipe, a second reaction pipe and a third reaction pipe nested in sequence. The first reaction pipe is filled with a thermocatalytic hydrogen production catalyst, and the space between the first reaction pipe and the second reaction pipe is filled with a photothermal catalytic hydrogen production catalyst. The outer wall of the second reaction pipe is provided with a photothermal catalytic hydrogen production catalyst with photothermal conversion characteristics.

4. The solar photothermal catalytic continuous hydrogen production system according to claim 1, characterized in that, The catalytic reaction pipeline is equipped with a reaction focusing component for heating the hydrogen-producing reactants.

5. The solar photothermal catalytic continuous hydrogen production system according to claim 1, characterized in that, The photothermal conversion preheating section also includes a heat storage circulation pipeline, and the heat storage device is installed on the heat storage circulation pipeline. The heat storage carrier in the photothermal conversion tube is circulated and heated through the heat storage circulation pipeline.

6. The solar photothermal catalytic continuous hydrogen production system according to claim 1, characterized in that, The photothermal conversion tube includes a heat-conducting pipe, an intermediate pipe, and a transparent pipe arranged sequentially from the inside to the outside. The heat-conducting pipe is used to flow the heat storage carrier, and the space between the heat-conducting pipe and the intermediate pipe is used to flow the hydrogen production reactants. The transparent pipe and the intermediate pipe are kept in a vacuum to achieve heat insulation.

7. The solar photothermal catalytic continuous hydrogen production system according to claim 6, characterized in that, The outer surface of the intermediate pipe is loaded with photothermal conversion material.

8. The solar photothermal catalytic continuous hydrogen production system according to claim 7, characterized in that, The outer surface of the heat-conducting pipe is provided with a heat-conducting enhanced microstructure.

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