A self-heating methanol reforming reaction system

Abstract

This invention belongs to the field of methanol reforming for hydrogen production technology, specifically relating to a self-heating methanol reforming reaction system, including a catalytic combustion system and a reforming purification system. The catalytic combustion system includes a heating zone, a tube array, and a tail gas emission zone, which are connected in sequence. The reforming purification system includes a reforming reaction zone, a heat exchange zone, a CO selective methanation reaction zone, and a waste heat recovery zone, which are also connected in sequence. A first coil is configured in the heat exchange zone and wound around the tube array. A second coil is configured in the waste heat recovery zone and wound around the tube array. This system integrates catalytic combustion, reforming for hydrogen production, CO selective methanation, and waste heat utilization into one unit. The reactor has a compact structure, high integration, and high thermal efficiency, meeting the lightweight design requirements for on-board methanol reforming for hydrogen production.

Description

Technical Field

[0001] This invention belongs to the field of methanol reforming hydrogen production technology, specifically relating to a self-heating methanol reforming reaction system. Background Technology

[0002] Self-heating methanol reforming technology is an important hydrogen production route for on-board methanol reforming hydrogen fuel cells. It utilizes methanol steam reforming to produce hydrogen-rich gas, and the heat of methanol catalytic combustion reaction provides the heat required for reforming hydrogen production, enabling on-demand hydrogen production. It solves the technical problems of hydrogen storage, transportation, and refueling in existing high-pressure hydrogen storage tanks for hydrogen fuel cells, and provides an effective solution to the hydrogen supply problem of proton exchange membrane fuel cells (PEMFC) in mobile applications.

[0003] However, the hydrogen-rich gas produced by methanol reforming typically contains 1–3% CO. The tolerance of PEMFC membrane electrode assemblies to CO is extremely low (<10 ppm), and excessively high CO concentrations can poison the PEMFC catalyst. Therefore, when using methanol reforming to supply hydrogen to fuel cells, a CO removal device must be installed between the methanol reforming reactor and the fuel cell to produce low-CO, hydrogen-rich gas that meets the requirements of PEMFCs. This typically increases the volume and mass of the methanol reforming hydrogen fuel cell system and reduces its energy density.

[0004] The purification of CO from hydrogen-rich gas is a key bottleneck in the application of methanol reforming to hydrogen production technology in PEMFCs. CO purification from hydrogen-rich gas can be achieved through various pathways, such as pressure swing adsorption (PSA), palladium membrane hydrogen permeation, selective CO methanation, and preferential CO oxidation. Among these, the reaction temperature of selective CO methanation is very close to that of methanol steam reforming, facilitating reactor integration design. Selective CO methanation does not require the introduction of additional reactants; it also offers a wide operating temperature range and good safety.

[0005] The methanol reforming hydrogen production unit adapted to PEFMC includes chemical reaction processes such as catalytic combustion, reforming hydrogen production, and CO methanation. The structural design of its methanol reforming hydrogen production reactor is particularly important. How to integrate all chemical reaction processes into one reactor and effectively design its thermal management system to improve the system's energy utilization rate is crucial for the efficient and economical operation of the entire methanol reforming technology and methanol reforming fuel cell system.

[0006] To improve the integration and energy efficiency of methanol reforming reactors, plate reactors are currently the most common type. However, the layered structure of plate reactors limits the amount of catalyst that can be packed, which restricts the hydrogen production capacity. In addition, the hydrogen-rich gas (H2) produced by methanol reforming has a content of 72% to 74%, and the hydrogen flow rate supplied to hydrogen fuel cells is much higher than that of high-pressure hydrogen storage tanks. Considering the hydrogen production capacity, tubular methanol reforming reactors are currently the preferred choice for commercial methanol reforming hydrogen production units.

[0007] Therefore, optimizing the thermal management structure of catalytic combustion, reforming for hydrogen production, selective CO methanation, reforming gas heat exchange, and waste heat recovery in methanol reforming fuel hydrogen production systems to improve the integration of tubular reactors, reduce heat loss, and increase heat exchange efficiency is a crucial technical challenge for methanol reforming for hydrogen production. Summary of the Invention

[0008] To address the problems of complex reaction operation units, large reforming and purification devices, low system energy utilization efficiency, and low integration in existing methanol reforming hydrogen production systems, the present invention aims to provide a self-heating methanol reforming reaction system that integrates CO selective methanation and coupled system thermal management.

[0009] To achieve the above objectives, the technical solution of the present invention is as follows.

[0010] This invention provides a self-heating methanol reforming reaction system, including a catalytic combustion system and a reforming purification system;

[0011] The catalytic combustion system includes a heating zone, a tube array, and an exhaust gas emission zone, which are connected in sequence; the heating zone and the exhaust gas emission zone are respectively located at both ends of the reforming and purification system, and the tube array is filled with catalyst particles.

[0012] The reforming and purification system includes a reforming reaction zone, a heat exchange zone, a CO selective methanation reaction zone, and a waste heat recovery zone, which are connected in sequence; the reforming reaction zone is filled with catalyst particles.

[0013] The heat exchange zone is equipped with a first coil, which is wound around the tubes. After the fluid exchanges heat through the first coil, it enters the reforming reaction zone and undergoes a reforming reaction under the catalysis of the catalyst particles to produce reforming gas.

[0014] The CO selective methanation reaction zone is filled with catalyst particles three; the reformed gas enters the CO selective methanation reaction zone after heat exchange in the heat exchange zone, and undergoes CO selective methanation reaction under the catalysis of the catalyst particles three to produce hydrogen-rich gas, which is discharged after heat exchange in the waste heat recovery zone.

[0015] The waste heat recovery zone is equipped with a second coil, which is wound around the tube. After the fluid 2 exchanges heat through the second coil, it enters the heating zone and the tube in sequence. Under the catalysis of the catalyst particles 1, a catalytic combustion reaction occurs to produce catalytic combustion exhaust gas, which is discharged after passing through the exhaust gas emission zone.

[0016] In a preferred embodiment, a heating structure is fitted on the outer wall of the heating zone, configured to preheat the fluid 2 within the heating zone.

[0017] In a preferred embodiment, a buffer zone one is provided on one side of the heating zone, a buffer zone two is provided on one side of the exhaust gas emission zone, and the two ends of the tube are respectively connected to the buffer zone one and the buffer zone two.

[0018] In a preferred embodiment, the system further includes a housing with at least three baffles configured to divide the housing into the reforming reaction zone, the heat exchange zone, the CO selective methanation reaction zone, and the waste heat recovery zone.

[0019] In a preferred embodiment, end plates are installed at both ends of the housing, and the two ends of the tubes are respectively inserted through the corresponding end plates.

[0020] In a preferred embodiment, the three baffles are staggered with openings to allow the reforming reaction zone, the heat exchange zone, the CO selective methanation reaction zone, and the waste heat recovery zone to be connected sequentially.

[0021] In a preferred embodiment, the first fluid is a reforming hydrogen production material, which is a methanol-water solution prepared by mixing methanol and water in a molar ratio of 1:1 to 1.5. Methanol-water solutions within this concentration range can be used for hydrogen production.

[0022] In a preferred embodiment, the second fluid is a mixture of methanol and air, or a mixture of H2-containing exhaust gas and air. The methanol-air mixture, or the mixture of H2-containing exhaust gas and air from the fuel cell anode, can both be used as catalytic combustion materials.

[0023] Preferably, the second fluid is a mixture of methanol and air, wherein the molar ratio of methanol to air is 0.1–0.2:1, preferably 0.14:1. Preferably, the second fluid is a mixture of H2-containing tail gas and air, wherein the molar ratio of H2-containing tail gas to air is 0.28–0.42:1. The H2-containing tail gas is the anode outlet tail gas of the hydrogen fuel cell, simply referred to as anode tail gas. Mixed gases within the above ratio range can all be used as catalytic combustion materials.

[0024] In a preferred embodiment, the first catalyst particle is a methanol catalytic combustion catalyst particle or a hydrogen catalytic combustion catalyst particle; the second catalyst particle is a reforming catalyst particle; and the third catalyst particle is a CO selective methanation catalyst particle.

[0025] In a preferred embodiment, the first catalyst particle is a Pt / Al2O3 particle; the second catalyst particle is a CuO / ZnO / Al2O3 particle; and the third catalyst particle is a Ni(Cl)3 particle. 0.1) / ZrO2 particles.

[0026] In a preferred embodiment, the number of tubes is multiple, and they are arranged in parallel within the reforming and purification system.

[0027] In a preferred embodiment, a catalytic combustion material inlet is provided on one side of the heating zone, and two fluid inlets and two fluid outlets are respectively provided at both ends of the second coil. The two fluid outlets are connected to the catalytic combustion material inlet through a pipe; a catalytic combustion exhaust gas outlet is provided on one side of the exhaust gas emission zone.

[0028] In a preferred embodiment, a reforming material inlet is provided on one side of the reforming reaction zone, and a fluid inlet and a fluid outlet are respectively provided at both ends of the first coil, with the fluid outlet connected to the reforming material inlet via a pipe.

[0029] The beneficial effects of this invention are:

[0030] 1. This invention integrates catalytic combustion, reforming for hydrogen production, selective CO methanation, and waste heat utilization into the same reactor. The reactor has a compact structure, high integration, and optimized thermal management system, thereby improving the system's energy efficiency.

[0031] 2. The self-heating methanol reforming reaction system of this invention has a more rational structural and process path design because the reforming reaction chamber and the reaction temperature of CO selective methanation in this methanol reforming hydrogen production reactor are relatively close, and the variation range of process temperature control parameters is small. This allows for effective regulation of the reaction temperatures required for each reaction, achieving efficient utilization of system energy. Under the process path designed for this reactor, the heat exchange of catalytic combustion, methanol steam reforming, CO selective methanation, and system tail gas waste heat is more in line with energy transfer efficiency, reducing heat loss caused by device pipeline connections and maximizing the utilization of reactor heat. This patent can solve the problems of hydrogen storage, transportation, and refueling, enabling low-cost hydrogen production in the market, meeting the requirements for on-board hydrogen supply for methanol reforming hydrogen fuel cells, and achieving the need for deep miniaturization of hydrogen production devices. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a self-heating methanol reforming reaction system with part of the shell removed, according to one embodiment of the present invention.

[0033] Figure 2 This is a schematic diagram of the structure of a self-heating methanol reforming reaction system provided in one embodiment of the present invention.

[0034] Figure 3 This is a schematic diagram of the connection structure between the tubes, end plates, and baffles in a self-heating methanol reforming reaction system provided in one embodiment of the present invention.

[0035] Figure 4 This is a cross-sectional schematic diagram of a self-heating methanol reforming reaction system provided in one embodiment of the present invention.

[0036] Figure 5 The flowchart illustrates the operation of a self-heating methanol reforming reaction system according to one embodiment of the present invention.

[0037] In the diagram, 1. Catalytic combustion material inlet; 2. Catalytic combustion exhaust gas outlet; 3. Reforming material inlet; 4. Hydrogen-rich gas outlet; 5. CO selective methanation catalyst packing port; 6. Fluid inlet 1; 7. Fluid outlet 1; 8. Fluid inlet 2; 9. Fluid outlet 2; 10. Flange;

[0038] 11. Heating structure; 12. Shell;

[0039] 13a. First end plate; 13b. Second end plate; 14a. First baffle plate; 14b. Second baffle plate; 14c. Third baffle plate; 15a. Opening in the first baffle plate; 15b. Opening in the second baffle plate; 15c. Opening in the third baffle plate; 16. Catalyst particles one; 17. Heating zone; 18. Buffer zone one; 19. Tube column; 20. Buffer zone two;

[0040] 21. Exhaust gas emission zone; 22. Reforming reaction zone; 23. Heat exchange zone; 24. CO selective methanation reaction zone; 25. Waste heat recovery zone; 26. Catalyst particle two; 27. Catalyst particle three; 28a. First coil; 28b. Second coil. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0042] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, it is intended to include any modifications and variations that fall within the scope of the claims and their equivalents.

[0044] Currently, most commercial methanol reforming hydrogen fuel cell technologies use high-temperature hydrogen fuel cells, but due to the technical challenges of high-temperature hydrogen fuel cell membranes, methanol reforming high-temperature fuel cells still face industrialization issues.

[0045] Methanol reforming low-temperature pure hydrogen fuel cells are currently the most mature and efficient fuel cell technology, and mass production has been achieved. However, low-temperature hydrogen fuel cells have high requirements for hydrogen sources. The reforming gas produced by online methanol reforming contains 0.5-3% CO. Even trace amounts of CO can poison the catalyst of PEMFC, leading to a decrease in battery efficiency. When using methanol reforming to produce hydrogen, the CO content in the reforming gas must be reduced to below 10 ppm.

[0046] Industrialized methanol reforming hydrogen production technology is relatively mature. The equipment generally uses pressure swing adsorption to remove CO from hydrogen-rich gas. This purification device has a simple process and a high degree of automation, but the equipment is complex and is only suitable for large-scale production in factories and other places. It is not suitable for CO removal in methanol reforming mobile online hydrogen production systems.

[0047] Common methods for CO removal in mobile online hydrogen production from methanol reforming include palladium membrane separation, CO selective methanation, and CO selective oxidation. Palladium membrane separation is costly and requires high temperature and pressure conditions, making its operation demanding. CO selective oxidation requires the introduction of additional air, which introduces gaseous impurities and increases the complexity of the equipment, hindering the lightweight design of the vehicle's powertrain. CO selective methanation, on the other hand, does not require an additional oxidant, its reaction apparatus is simpler and more compact, and it offers advantages such as simple process control and high energy efficiency. It is better suited for removing CO impurities from the ammonia-rich product gas of on-site methanol reforming, providing a hydrogen source for on-board low-temperature hydrogen fuel cells.

[0048] For online hydrogen production via methanol reforming for low-temperature hydrogen fuel cells, existing technologies involve miniaturizing large industrial units. Each reaction unit—methanol catalytic combustion (or hydrogen fuel cell with H2 exhaust gas), methanol steam reforming, CO selective methanation, and waste heat recycling—is independently designed and connected via external pipelines. This results in heat loss, low hydrogen production efficiency, and a large system size. The root cause of this problem lies in the poor design of the methanol reforming reactor and process pathway, failing to achieve optimal space utilization for the methanol reforming hydrogen production system.

[0049] Currently, methanol reforming hydrogen production reactors both domestically and internationally are mainly concentrated on microreactors, most of which are plate-type layered microchannel structures. However, this structure limits the amount of catalyst that can be packed, and the hydrogen supply capacity of these reactors is mostly below 500 L / hr. While microchannel reactors have achieved excellent results in miniaturized hydrogen production, they face various challenges in scaling up. The relatively low hydrogen production capacity of microchannel reactors cannot meet the needs of high-energy-consuming applications such as vehicle engines, hydrogen fuel cells, or outdoor power generation.

[0050] Traditional methanol reforming hydrogen production systems are mostly composed of packed-bed tubular reactors and shell-and-tube reactors. The system consists of multiple adiabatic packed-bed reactors connected in series. The heat and pressure carried by the high-temperature gas exiting the packed-bed reactor can be recovered through heat exchangers and compressors. However, due to the poor heat transfer performance of the catalyst bed in packed-bed reactors, temperature runaway phenomena ("runaway") are prone to occur inside the reactor. In strongly exothermic or endothermic reactions, this can easily lead to uneven distribution within the bed, thereby reducing the performance of catalytic combustion, reforming hydrogen production, and CO selective methanation.

[0051] To address the problems of complex reaction operation units, large reforming and purification devices, low system energy utilization efficiency, and low integration in the aforementioned methanol reforming hydrogen production systems, and considering that the hydrogen supply capacity of existing miniaturized mobile online methanol reforming hydrogen production systems cannot meet the hydrogen supply requirements of high-power on-board hydrogen fuel cells, one embodiment of this invention provides a self-heating methanol reforming reaction system. This system improves the overall system energy utilization efficiency by effectively utilizing methanol catalytic combustion or fuel cell anode tail gas combustion. Through the integrated design of catalytic combustion, reforming hydrogen production, CO selective methanation, and waste heat recycling within the same reactor, the bed temperature distribution of catalyst combustion, reforming hydrogen production, and CO selective methanation reactions is further optimized, achieving a more compact, efficient, and miniaturized mobile online methanol reforming hydrogen production system.

[0052] The reactor incorporates catalytic combustion within the tube side and features electric heating at the catalytic combustion inlet, enabling rapid start-up and shutdown of the hydrogen production system and shortening start-up time. Simultaneously, the reactor integrates methanol steam reforming, CO selective methanation, and system waste heat recycling into the shell side, with each reaction chamber separated by baffles and interconnected sequentially through baffle openings.

[0053] The reactor's structure and process pathway are more rationally designed because the reaction temperatures of the reforming chamber and CO selective methanation in this methanol reforming hydrogen production reactor are relatively close, resulting in minimal variation in process temperature control parameters. This allows for effective regulation of the reaction temperatures required for each reaction, achieving high-efficiency energy utilization of the system. Under this reactor's designed process pathway, the heat exchange between catalytic combustion, methanol steam reforming, CO selective methanation, and system exhaust waste heat is more aligned with energy transfer efficiency, reducing heat loss from pipeline connections and maximizing the utilization of reactor heat. This patent can solve the problems of hydrogen storage, transportation, and refueling, enabling low-cost hydrogen production for the market, meeting the requirements for on-board hydrogen supply in methanol reforming hydrogen fuel cells, and achieving the need for deep miniaturization of hydrogen production equipment.

[0054] Based on this, one embodiment of the present invention provides a self-heating methanol reforming reaction system, including a catalytic combustion system and a reforming purification system. The self-heating methanol reforming reaction system of the present invention integrates the catalytic combustion, reforming hydrogen production, CO selective methanation, and system waste heat utilization of the methanol reforming tubular reactor into a single design, improving the integration of the tubular reactor, optimizing the device's thermal management system, and increasing the system's energy efficiency.

[0055] The catalytic combustion system includes a heating zone 17, a tube array 19, and an exhaust gas emission zone 21, which are connected in sequence; the heating zone 17 and the exhaust gas emission zone 21 are respectively arranged at both ends of the reforming and purification system, and the tube array 19 is filled with catalyst particles 16.

[0056] The reforming and purification system includes a reforming reaction zone 22, a heat exchange zone 23, a CO selective methanation reaction zone 24, and a waste heat recovery zone 25, which are connected in sequence; the reforming reaction zone 22 is filled with catalyst particles 26.

[0057] The heat exchange zone 23 is equipped with a first coil 28a, which is wound around the tube 19. After the fluid exchanges heat through the first coil 28a, it enters the reforming reaction zone 22 and undergoes a reforming reaction under the catalysis of the catalyst particles 26 to produce reformed gas. The reformed gas, or simply reformed gas, is mainly converted from methanol steam reforming and is a fuel mainly containing hydrogen. The reformed gas is mainly used to supply fuel cells.

[0058] The CO selective methanation reaction zone 24 is filled with catalyst particles 27. Reformed gas enters the CO selective methanation reaction zone 24 after heat exchange in the heat exchange zone 23, and undergoes a CO selective methanation reaction under the catalysis of the catalyst particles 27 to produce hydrogen-rich gas, which is then discharged after heat exchange in the waste heat recovery zone 25. The waste heat recovery zone 25 has a hydrogen-rich gas outlet 4 on one side, configured to discharge hydrogen-rich gas. Generally, hydrogen-rich gas refers to gas containing a relatively high amount of hydrogen; the hydrogen content depends on specific application requirements and preparation conditions.

[0059] The waste heat recovery zone 25 is equipped with a second coil 28b, which is wound around the tube 19. Fluid 2, after heat exchange via the second coil 28b, sequentially enters the heating zone 17 and the tube 19, where it undergoes a catalytic combustion reaction under the catalysis of the catalyst particles 16, producing catalytic combustion exhaust gas, which is then discharged through the exhaust gas emission zone 21. The exhaust gas emission zone 21 has a catalytic combustion exhaust gas outlet 2 on one side, configured to discharge the catalytic combustion exhaust gas.

[0060] To facilitate the filling of catalyst particles 27, a CO selective methanation catalyst filling port 5 is provided on one side of the CO selective methanation reaction zone 24 to facilitate the replenishment of catalyst particles 27.

[0061] In a preferred embodiment, to reduce the reactor start-up time, a heating structure 11 is fitted onto the outer wall of the heating zone 17, configured to preheat the fluid 2 within the heating zone. Preferably, the heating structure 11 is an electric heating jacket, which is connected to a power supply via wires. The power supply activates the electric heating jacket to generate heat, which is used to preheat the fluid 2 within the heating zone 17. This facilitates the reaction of the preheated fluid 2 after it enters the tube 19 and comes into contact with the catalyst particles 16 in the tube 19, under the catalysis of the catalyst particles 16.

[0062] In a preferred embodiment, a buffer zone 18 is provided on one side of the heating zone 17, and a buffer zone 20 is provided on one side of the exhaust gas emission zone 21. The two ends of the tube 19 are respectively connected to the buffer zone 18 and the buffer zone 20.

[0063] In a preferred embodiment, the system further includes a shell 12, which can be wrapped with an insulating material layer to reduce heat loss from the reactor. The insulating material layer serves to prevent heat loss from the shell. The insulating material layer is a commercially available insulating material layer. This invention does not limit the specific material of the insulating material layer, as long as the insulating material can wrap around the outside of the shell 12 and effectively prevent heat loss from the shell. The shell 12 is equipped with at least three baffles, configured to divide the shell 12 into the reforming reaction zone 22, the heat exchange zone 23, the CO selective methanation reaction zone 24, and the waste heat recovery zone 15. For example, the shell 12 is equipped with three baffles, respectively designated as the first baffle 14a, the second baffle 14b, and the third baffle 14c. The inner cavity of the shell 12 is divided into four chambers by the three baffles, and each chamber is separated by the first baffle 14a, the second baffle 14b, and the third baffle 14c.

[0064] In a preferred embodiment, the three baffle plates are staggered with openings to sequentially connect the reforming reaction zone 22, the heat exchange zone 23, the CO selective methanation reaction zone 24, and the waste heat recovery zone 25. For example, the lower region of the first baffle plate 14a has multiple first baffle plate openings 15a, the upper region of the second baffle plate 14b has multiple second baffle plate openings 15b, and the lower region of the third baffle plate 14c has multiple third baffle plate openings 15c. Thus, the chambers are interconnected through the first baffle plate openings 15a, second baffle plate openings 15b, and third baffle plate openings 15c. This invention does not limit the specific positions of the first baffle plate openings 15a, second baffle plate openings 15b, and third baffle plate openings 15c on the corresponding baffle plates. Of course, the staggered arrangement of the openings on the corresponding baffle plates helps to extend the gas reaction path, thereby realizing the heat exchange utilization of the system energy.

[0065] In a preferred embodiment, end plates are installed at both ends of the housing 12, and the two ends of the tubes are respectively passed through the corresponding end plates. The end plates separate the reforming and purification system, the heating zone 17, and the exhaust gas emission zone 21, making each zone independent and non-communicating. For example, the two end plates are designated as first end plate 13a and second end plate 13b, respectively. First end plate 13a is located on one side of the heating zone 17, and second end plate is located on one side of the exhaust gas emission zone 21. The two ends of the tubes 19 are respectively passed through first end plate 13a and second end plate 13b. The first end plate 13a is mainly used to separate the heating zone 17 from the reforming reaction zone 22, preventing the two zones from communicating; the second end plate 13b is mainly used to separate the exhaust gas emission zone 21 from the waste heat recovery zone 15, preventing the two zones from communicating.

[0066] like Figure 4 The shell 12, tubes 19, end plates 13a and 13b are made of metallic materials, such as stainless steel. The baffles 14a, 14b and 14c are made of insulating materials, such as a hard metal combining composite materials and stainless steel. The hard metal ensures both the structural strength of the baffles and the insulation to ensure that the temperatures in adjacent reaction chambers do not affect each other.

[0067] During manufacturing, flanges 10 are installed at both ends of the shell 12, which is made of stainless steel pipe, serving as the main body of the shell 12. Holes are pre-drilled on the upper and lower sides of the shell 12 for welding the reforming material inlet 3, hydrogen-rich gas outlet 4, fluid inlet 6, fluid outlet 7, fluid outlet 8, and fluid outlet 9. After the internal tubes 19, end plates, and baffle plate structure are assembled, the end plates are welded to the stainless steel pipes, and an arc-shaped end cap is welded to each end of the shell 12, with the two sealed together by flanges 10. The end caps are pre-drilled for welding the catalytic combustion material inlet 1 and the catalytic combustion exhaust gas outlet 2.

[0068] In a preferred embodiment, the fluid is a reforming hydrogen production material, which is a methanol-water solution prepared by mixing methanol and water in a molar ratio of 1:1.3.

[0069] In a preferred embodiment, the second fluid is a mixture of methanol and air, or a mixture of H2-containing exhaust gas and air. The methanol-air mixture, or the mixture of H2-containing exhaust gas and air from the fuel cell anode, can both be used as catalytic combustion materials.

[0070] Preferably, the second fluid is a mixture of methanol and air, wherein the molar ratio of methanol to air is 0.1–0.2:1, preferably 0.14:1, and for example, 0.1:1, 0.12:1, 0.14:1, 0.16:1, 0.18:1, 0.2:1, etc. Preferably, the second fluid is a mixture of H2-containing tail gas and air, wherein the molar ratio of H2-containing tail gas to air is 0.28–0.42:1, for example, 0.28:1, 0.3:1, 0.32:1, 0.34:1, 0.36:1, 0.38:1, 0.4:1, 0.42:1, etc. The H2-containing tail gas is the anode outlet tail gas of the hydrogen fuel cell, simply referred to as anode tail gas. Mixed gases within the above ratio range can all be used as catalytic combustion materials.

[0071] In a preferred embodiment, catalyst particle 16 is a methanol catalytic combustion catalyst particle or a hydrogen catalytic combustion catalyst particle; catalyst particle 26 is a reforming catalyst particle; and catalyst particle 27 is a CO selective methanation catalyst particle.

[0072] In a preferred embodiment, catalyst particle 16 is a Pt / Al2O3 particle; catalyst particle 26 is a CuO / ZnO / Al2O3 particle; and catalyst particle 27 is a Ni(Cl)3 particle. 0.1 ) / ZrO2 particles.

[0073] In a preferred embodiment, the number of tubes 19 is multiple, and they are arranged in parallel within the reforming and purification system.

[0074] In a preferred embodiment, a catalytic combustion material inlet 1 is provided on one side of the heating zone 17, and two fluid inlets 8 and two fluid outlets 9 are respectively provided at both ends of the second coil 28b. The two fluid outlets 9 are connected to the catalytic combustion material inlet 1 through a pipe; a catalytic combustion exhaust gas outlet 2 is provided on one side of the exhaust gas emission zone 21.

[0075] In a preferred embodiment, a reforming material inlet 3 is provided on one side of the reforming reaction zone 22, and a fluid inlet 6 and a fluid outlet 7 are respectively provided at both ends of the first coil 28a. The fluid outlet 7 is connected to the reforming material inlet 3 through a pipe.

[0076] In the above embodiments of the present invention, the system has two fluid reaction sections: catalytic combustion and reforming / purification. These two sections are not interconnected, but the chemical reactions occurring in both sections can exchange heat. The paths traversed by the two fluid sections are referred to as zones in this patent. One path is the catalytic combustion zone, and the other is the reforming / purification zone. The catalytic combustion zone can be either a methanol-air catalytic combustion reaction or a reaction containing H2-containing exhaust gas, such as the exhaust gas from the anode outlet of a hydrogen fuel cell.

[0077] The catalytic combustion zone includes a heating zone 17, a buffer zone 18, a tube array 19, a second buffer zone 20, and a tail gas emission zone 21. These zones are interconnected in sequence. Meanwhile, the tube array 19 is filled with catalyst particles 16. The catalytic combustion material is tail gas containing H2, such as tail gas from the anode outlet of a hydrogen fuel cell or methanol catalytic combustion reaction. In this patent, methanol and air catalytic combustion reaction is preferred, and Pt / Al2O3 catalyst is preferred.

[0078] The reforming and purification zone is located within the reactor shell and includes a reforming reaction zone 22, a heat exchange zone 23, a CO selective methanation reaction zone 24, and a waste heat recovery zone 25. Each chamber is separated by a first baffle plate 14a, a second baffle plate 14b, and a third baffle plate 14c, forming individual chambers. Fluids in each chamber are interconnected through openings in the baffle plates. Figure 3 and Figure 4 As shown, the reformed material undergoes methanol steam reforming to produce hydrogen sequentially. After heat exchange in the heat exchange chamber, it enters the CO selective methanation reaction zone 24 for CO purification. The purified hydrogen-rich gas and the waste heat from catalytic combustion are recovered and utilized. The reforming reaction zone 22 is filled with catalyst particles 26, with CuO / ZnO / Al2O3 being the preferred reforming catalyst. The CO selective methanation reaction zone 24 is filled with catalyst particles 27, with Ni(Cl) being the preferred CO selective methanation catalyst. 0.1 ) / ZrO2 particles.

[0079] The reforming and purification area includes two heat exchange chambers: heat exchange zone 23 and waste heat recovery zone 25.

[0080] The heat exchange zone 23 can exchange heat between the reformed gas and the cold fluid. The reaction temperature of the CO selective methanation reaction zone 24 is adjusted through heat exchange to control the CO purification temperature within the optimal reaction temperature range. The heat exchange zone 23 is equipped with a first coil 28a. Fluid 1 is introduced into the first coil 28a through the fluid 1 inlet 6. After exchanging heat with the reformed gas, it flows out through the fluid 1 outlet 7. Fluid 1 preferentially selects reformed hydrogen production materials, such as liquid methanol-water with a molar ratio of 1:1.3, to preheat the reformed gas and improve the energy utilization rate of the methanol reforming hydrogen production reactor.

[0081] Waste heat recovery zone 25 can recover and utilize the waste heat from hydrogen-rich gas, catalytic combustion tail gas, and cold fluid II, reducing system heat loss and improving the energy utilization rate of the entire methanol reforming reactor. Waste heat recovery zone 25 is equipped with a second coil 28b. Fluid II enters the second coil 28b through fluid II inlet 8, exchanges heat with hydrogen-rich gas, and then flows out through fluid II outlet 9. Fluid II preferentially uses liquid methanol to preheat the methanol catalytic combustion material, thereby improving the energy utilization rate of the methanol reforming hydrogen production reactor.

[0082] The working process of the self-heating methanol reforming reaction system provided in one embodiment of the present invention is as follows:

[0083] During the start-up phase, liquid methanol and air are introduced into the catalytic combustion material inlet 1 and preheated by the heating structure 11. The preheated gas enters the buffer zone 18 for mixing, and the mixed gas enters the tube 19 to carry out the methanol catalytic combustion reaction, releasing the heat of reaction and providing the required heat for the reforming and purification area.

[0084] After the catalytic combustion reaction stabilizes, cold fluid two—methanol liquid—is introduced into the second coil 28b through fluid two inlet 8 for preheating. The preheated fluid one is then introduced into the catalytic combustion material inlet 1, and electric heating is stopped. After heat exchange and recycling, the catalytic combustion exhaust gas is combined and discharged through the exhaust gas emission zone 21 via buffer zone two 20. During steady-state operation, the catalytic combustion material is supplied by the anode exhaust gas from the fuel cell. The entire process of the catalytic combustion zone is as follows: Figure 5 As indicated by the middle arrow A.

[0085] Further, fluid one—methanol-water liquid—is introduced into the first coil 28a for heat exchange through fluid two inlet 6. After the reactor stabilizes at the required reforming temperature, the preheated fluid two is introduced into the reforming material inlet 3 and enters the reforming reaction zone 22. Under the catalysis of catalyst particles two 26, a reforming reaction occurs to produce reformed gas. The reformed gas enters the heat exchange zone 23 through the opening 15a of the first baffle plate for heat exchange. Then, the reformed gas enters the CO selective methanation reaction zone 24 through the opening 15b of the second baffle plate. Under the catalysis of catalyst particles three 27, a CO selective methanation reaction occurs to produce hydrogen-rich gas. The hydrogen-rich gas flows into the waste heat recovery zone 25 through the opening 15c of the third baffle plate. At this point, the hydrogen-rich gas tail gas and the catalytic combustion tail gas still have waste heat, which can be collected and utilized. The process then proceeds to the next step. The entire process of the reforming and purification area is as follows: Figure 5 As indicated by the middle arrows B, C, and D.

[0086] The self-heating methanol reforming reaction system provided in one embodiment of the present invention includes two parts: a catalytic combustion reaction zone and a reforming and purification reaction zone. These two zones are not interconnected but can exchange heat. The catalytic combustion zone comprises an electric heating chamber and a catalytic combustion reaction chamber. The electric heating provides auxiliary heating, shortening the reactor start-up time, while the catalytic combustion reaction chamber provides the necessary heat to the reforming zone. The reforming and purification reaction zone comprises four parts: a reforming reaction chamber, a heat exchange chamber, a CO selective methanation reaction chamber, and a waste heat recovery chamber. These chambers are separated by baffles but are sequentially interconnected. This self-heating methanol reforming reaction system integrates methanol catalytic combustion (or H2-containing tail gas), methanol steam reforming, CO selective methanation, and system preheating and recycling into a single unit. The reactor has a compact structure, high integration, and high thermal efficiency, meeting the lightweight design requirements for on-board methanol reforming for hydrogen production.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A self-heating methanol reforming reaction system, characterized in that, Including catalytic combustion systems and reforming purification systems; The catalytic combustion system includes a heating zone, a tube array, and an exhaust gas emission zone, which are connected in sequence; the heating zone and the exhaust gas emission zone are respectively located at both ends of the reforming and purification system, and the tube array is filled with catalyst particles. The reforming and purification system includes a reforming reaction zone, a heat exchange zone, a CO selective methanation reaction zone, and a waste heat recovery zone, which are connected in sequence; the reforming reaction zone is filled with catalyst particles. The heat exchange zone is equipped with a first coil, which is wound around the tubes. After the fluid exchanges heat through the first coil, it enters the reforming reaction zone and undergoes a reforming reaction under the catalysis of the catalyst particles to produce reforming gas. The CO selective methanation reaction zone is filled with catalyst particles three; the reformed gas enters the CO selective methanation reaction zone after heat exchange in the heat exchange zone, and undergoes CO selective methanation reaction under the catalysis of the catalyst particles three to produce hydrogen-rich gas, which is discharged after heat exchange in the waste heat recovery zone. The waste heat recovery zone is equipped with a second coil, which is wound around the tube. After the second coil exchanges heat, the fluid enters the heating zone and the tube in sequence. Under the catalysis of the catalyst particles, a catalytic combustion reaction occurs to produce catalytic combustion exhaust gas, which is discharged after passing through the exhaust gas emission zone. It also includes a shell, in which at least three baffles are disposed, configured to divide the shell into the reforming reaction zone, the heat exchange zone, the CO selective methanation reaction zone, and the waste heat recovery zone; each of the three baffles is provided with staggered openings so that the reforming reaction zone, the heat exchange zone, the CO selective methanation reaction zone, and the waste heat recovery zone are connected in sequence; A catalytic combustion material inlet is provided on one side of the heating zone, and two fluid inlets and two fluid outlets are provided at both ends of the second coil, respectively. The two fluid outlets are connected to the catalytic combustion material inlet through a pipe; a catalytic combustion exhaust gas outlet is provided on one side of the exhaust gas emission zone.

2. The self-heating methanol reforming reaction system according to claim 1, characterized in that, A heating structure is fitted on the outer wall of the heating zone, configured to preheat the fluid 2 within the heating zone.

3. The self-heating methanol reforming reaction system according to claim 1, characterized in that, A buffer zone one is configured on one side of the heating zone, and a buffer zone two is configured on one side of the exhaust gas emission zone. The two ends of the tube are respectively connected to the buffer zone one and the buffer zone two.

4. The self-heating methanol reforming reaction system according to claim 1, characterized in that, The first fluid is a reforming hydrogen production material, which is a methanol-water solution prepared by mixing methanol and water in a molar ratio of 1:1 to 1.

5.

5. The self-heating methanol reforming reaction system according to claim 1, characterized in that, The second fluid is a mixture of methanol and air, or a mixture of H2-containing tail gas and air.

6. The self-heating methanol reforming reaction system according to claim 1, characterized in that, The first catalyst particle is a methanol catalytic combustion catalyst particle or a hydrogen catalytic combustion catalyst particle; the second catalyst particle is a reforming catalyst particle; and the third catalyst particle is a CO selective methanation catalyst particle.

7. The self-heating methanol reforming reaction system according to claim 1, characterized in that, A reforming material inlet is provided on one side of the reforming reaction zone, and a fluid inlet and a fluid outlet are respectively provided at both ends of the first coil. The fluid outlet is connected to the reforming material inlet through a pipeline.

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