Power generation system and method of diesel reforming hydrogen production coupled proton exchange membrane fuel cell

Abstract

The invention provides a diesel reforming hydrogen production coupled proton exchange membrane fuel cell power generation system and method, the power generation system comprises a diesel reforming reactor, a palladium membrane reactor, a water gas reactor and a PEMFC stack; an outlet of the diesel reforming reactor is connected with an inlet of the water gas reactor, an outlet of the water gas reactor is connected with an inlet of the palladium membrane reactor, and a hydrogen outlet of the palladium membrane reactor is connected with an anode inlet of the PEMFC electric pile. According to the invention, hydrogen is produced by reforming diesel oil, hydrogen storage is changed into oil storage, hydrogen is produced on site, and the hydrogen is produced and used instantly, so that expensive storage and transportation links such as high-pressure bottles and low-temperature tanks are omitted, the safety is better, and three major pain points of traditional hydrogen storage in energy consumption, cost and infrastructure are thoroughly avoided.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen power generation technology, specifically relating to a power generation system and method for a diesel reforming hydrogen production coupled with a proton exchange membrane fuel cell. Background Technology

[0002] With the continuous growth of energy demand and the increasing awareness of environmental protection, hydrogen energy, as a clean and efficient energy carrier, has received widespread attention. Proton exchange membrane fuel cells (PEMFCs) have advantages such as high energy conversion efficiency and environmental friendliness, and are considered an ideal choice for future distributed power generation and mobile power sources. However, hydrogen storage and transportation have always been one of the key issues restricting the development of PEMFCs. Traditional hydrogen storage technologies mainly include three types: high-pressure gaseous hydrogen storage, cryogenic liquid hydrogen storage, and solid-state hydrogen storage. High-pressure gaseous hydrogen storage equipment is simple and has a fast charging and discharging speed, but it is threatened by hydrogen embrittlement and high pressure; cryogenic liquid hydrogen storage has high density, but liquefaction consumes a lot of energy, the equipment is expensive, and operation is difficult; solid-state hydrogen storage has good safety and high volume utilization, but hydrogen absorption and desorption are slow, cycle decay is rapid, and thermal management is complex. It is evident that traditional hydrogen storage methods cannot achieve a good balance between energy consumption, cost, and safety. Summary of the Invention

[0003] In view of the problems of hydrogen storage, transportation and safety in existing PEMFC power generation technology, the present invention aims to provide a power generation system and method for diesel reforming to produce hydrogen coupled with proton exchange membrane fuel cells.

[0004] This invention is achieved through the following technical solution: In a first aspect, the present invention provides a power generation system for a diesel reforming hydrogen production coupled with a proton exchange membrane fuel cell, comprising: a diesel reforming reactor, a palladium membrane reactor, a water gas reactor, and a PEMFC stack; the outlet of the diesel reforming reactor is connected to the inlet of the water gas reactor, the outlet of the water gas reactor is connected to the inlet of the palladium membrane reactor, and the hydrogen outlet of the palladium membrane reactor is connected to the anode inlet of the PEMFC stack.

[0005] Preferably, the power generation system of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell further includes a steam generator, a diesel desulfurizer, a mixer, and a first heat exchanger; the outlet of the steam generator is connected to the first inlet of the mixer, the outlet of the diesel desulfurizer is connected to the second inlet of the mixer, the outlet of the mixer is connected to the cold fluid inlet of the first heat exchanger, and the cold fluid outlet of the first heat exchanger is connected to the inlet of the diesel reforming reactor.

[0006] Preferably, the power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell further includes a second heat exchanger; the outlet of the diesel reforming reactor is connected to the hot fluid inlet of the second heat exchanger, and the hot fluid outlet of the second heat exchanger is connected to the inlet of the water gas reactor.

[0007] Preferably, the water-gas reactor includes a first water-gas reactor and a second water-gas reactor; the hot fluid outlet of the second heat exchanger is connected to the inlet of the first water-gas reactor, the outlet of the first water-gas reactor is connected to the inlet of the second water-gas reactor, and the outlet of the second water-gas reactor is connected to the inlet of the palladium membrane reactor.

[0008] Preferably, the power generation system of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell further includes a third heat exchanger, wherein the hydrogen outlet of the palladium membrane reactor is connected to the hot fluid inlet of the third heat exchanger, and the hot fluid outlet of the third heat exchanger is connected to the anode inlet of the PEMFC stack.

[0009] Furthermore, the power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell also includes a buffer tank, the hot fluid outlet of the third heat exchanger is connected to the inlet of the buffer tank, and the outlet of the buffer tank is connected to the anode inlet of the PEMFC stack.

[0010] Preferably, the power generation system of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell further includes a condenser; the exhaust gas outlet of the palladium membrane reactor is connected to the inlet of the condenser, the gas outlet of the condenser outputs gas, and the liquid outlet of the condenser outputs water.

[0011] In a second aspect, the present invention provides a method for generating electricity using a diesel reforming-to-hydrogen coupled proton exchange membrane fuel cell, comprising: S1, diesel and water vapor are mixed and reformed to produce the first mixture; S2, the first mixture is subjected to a water-gas shift reaction to obtain the second mixture; S3, the second mixed gas is separated by a palladium membrane, and the separated hydrogen is sent to the PEMFC for power generation.

[0012] Preferably, S2 specifically involves: first, subjecting the first mixed gas to a high-temperature water-gas shift reaction at 350-450℃ to obtain the product, and then subjecting it to a low-temperature water-gas shift reaction at 200-260℃ to obtain the second mixed gas. Furthermore, S3 specifically involves heating the second mixed gas to 350-500°C, then separating it through a palladium membrane, and sending the separated hydrogen gas into a PEMFC for power generation.

[0013] Compared with the prior art, the present invention has the following beneficial effects: This invention couples a diesel reforming reactor with a PEMFC stack. The diesel reforming reactor converts diesel fuel into hydrogen-containing syngas, which is then used to supply hydrogen to the PEMFC for power generation. This invention utilizes diesel reforming to produce hydrogen, transforming "hydrogen storage" into "oil storage," enabling on-site hydrogen production and immediate use. It eliminates expensive storage and transportation links such as high-pressure cylinders and cryogenic tanks, and offers better safety, completely bypassing the three major pain points of traditional hydrogen storage: energy consumption, cost, and infrastructure. Simultaneously, a water-gas reactor is used to perform water-gas shift conversion (WGS) on the hydrogen-rich syngas, causing CO to react and generate CO2, avoiding the poisoning effect of CO on the catalyst in the subsequent PEMFC stack. This invention employs a palladium membrane to separate the syngas, achieving efficient hydrogen purification. The purified high-purity hydrogen is then delivered to the anode of the PEMFC stack, completing the conversion of chemical energy into electrical energy. Palladium membrane purification significantly improves the purity of the hydrogen entering the PEMFC stack, further avoiding catalyst poisoning caused by CO and extending the lifespan of the PEMFC stack. In summary, this invention solves the problems of hydrogen storage and transportation, reduces costs and safety hazards, and has strong fuel adaptability, applicable to diesel, biodiesel, aviation kerosene, etc. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of a power generation system for a diesel reforming hydrogen production coupled with a proton exchange membrane fuel cell, according to one embodiment of the present invention.

[0016] Figure 2 This is a schematic diagram of a power generation system for a diesel reforming hydrogen production coupled with a proton exchange membrane fuel cell, according to another embodiment of the present invention.

[0017] In the diagram: 1 is the first metering pump, 2 is the second metering pump, 3 is the steam generator, 4 is the mixer, 5 is the first heat exchanger, 6 is the diesel reforming reactor, 7 is the second heat exchanger, 8 is the first water-gas reactor, 9 is the second water-gas reactor, 10 is the palladium membrane reactor, 11 is the third heat exchanger, 12 is the buffer tank, 13 is the PEMFC stack, 14 is the condenser, 15 is the water storage tank, and 16 is the diesel desulfurizer. Detailed Implementation

[0018] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0019] It should be noted that the process equipment or apparatus not specifically mentioned in the following embodiments are all conventional equipment or apparatus in the art.

[0020] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or apparatuses. Furthermore, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not intended to limit the order of the method steps or define the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0021] Furthermore, it should be noted that the terms "first," "second," etc., used in this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Moreover, unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly, for example, referring to a fixed connection or a detachable connection; a direct connection or an indirect connection via an intermediate medium; or a connection within two components.

[0022] refer to Figure 1 The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell of the present invention includes: a diesel reforming reactor 6, a palladium membrane reactor 10, a water gas reactor and a PEMFC stack 13; the outlet of the diesel reforming reactor 6 is connected to the inlet of the water gas reactor, the outlet of the water gas reactor is connected to the inlet of the palladium membrane reactor 10, and the hydrogen outlet of the palladium membrane reactor 10 is connected to the anode inlet of the PEMFC stack 13.

[0023] This invention couples a diesel reforming reactor 6 with a PEMFC stack 13. The diesel reforming reactor 6 converts diesel into hydrogen-containing syngas, which is then used to provide hydrogen for the PEMFC to generate electricity. This invention utilizes diesel reforming to produce hydrogen, transforming "hydrogen storage" into "oil storage," enabling on-site hydrogen production and immediate use. It eliminates expensive storage and transportation links such as high-pressure cylinders and cryogenic tanks, and offers better safety, completely bypassing the three major pain points of traditional hydrogen storage in terms of energy consumption, cost, and infrastructure.

[0024] The hydrogen-rich syngas generated during the diesel reforming process contains impurities such as CO, CO2, and CH4. CO, in particular, poisons the catalyst in the PEMFC stack 13, requiring its concentration to be reduced to below 10 ppm. Therefore, this invention utilizes a water-gas reactor to perform water-gas conversion on the hydrogen-rich syngas, causing CO to react and generate CO2. Simultaneously, to increase the hydrogen concentration, this invention employs a palladium membrane for syngas separation. Due to its excellent selective hydrogen permeation performance, the palladium membrane can achieve efficient hydrogen purification through a "dissolution-diffusion" mechanism. The purified high-purity hydrogen is drawn from the hydrogen outlet of the palladium membrane reactor 10 and transported to the anode of the PEMFC stack 13. Under the action of the catalyst, an oxidation reaction occurs, releasing electrons. After doing work through the external circuit, the electrons combine with oxygen at the cathode to generate water, completing the conversion of chemical energy into electrical energy. The presence of the palladium membrane purification stage significantly improves the purity of the hydrogen entering the PEMFC stack 13, effectively avoiding catalyst poisoning caused by CO and extending the service life of the PEMFC stack 13.

[0025] The diesel reforming reactor 6 can adopt a fixed-bed tubular structure, filled with nickel-based or precious metal catalysts, with an operating temperature range of 700-800℃ and a pressure of 0.5-1 MPa, and is suitable for diesel fuels with long-chain alkanes as the main component.

[0026] In some embodiments of the present invention, the palladium membrane in the palladium membrane reactor 10 may be a dense palladium or palladium alloy film (such as Pd-Ag, Pd-Cu), with a thickness of generally 5-50 μm. The support for the palladium membrane may be a porous stainless steel or ceramic substrate. The operating temperature is controlled at 350-500℃, and the pressure difference on both sides is maintained at 400-800 kPa to drive the selective diffusion of hydrogen.

[0027] In some embodiments of the present invention, the PEMFC stack 13 is composed of multiple single cells connected in series, uses a perfluorosulfonic acid type proton exchange membrane (such as the Nafion® series), operates at a temperature of 60-90℃, and has the characteristics of fast start-up, high efficiency, and sensitive response.

[0028] In some embodiments of the present invention, the power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell further includes a steam generator 3, a diesel desulfurizer 16, a mixer 4, and a first heat exchanger 5; the outlet of the steam generator 3 is connected to the first inlet of the mixer 4, the outlet of the diesel desulfurizer 16 is connected to the second inlet of the mixer 4, the outlet of the mixer 4 is connected to the cold fluid inlet of the first heat exchanger 5, and the cold fluid outlet of the first heat exchanger 5 is connected to the inlet of the diesel reforming reactor 6.

[0029] By introducing a steam generator 3, a diesel desulfurizer 16, a mixer 4, and a first heat exchanger 5, the state control of fuel and water vapor before entering the diesel reforming reactor 6 is achieved. Specifically, the steam generator 3 converts liquid water into high-temperature, high-pressure water vapor, providing gaseous reactants for the subsequent reforming reaction; the diesel desulfurizer 16 removes sulfur compounds from the diesel fuel, preventing them from generating hydrogen sulfide at high temperatures that could poison the reforming catalyst; the mixer 4 ensures uniform mixing of the desulfurized diesel vapor and high-temperature water vapor, guaranteeing precise control of the water-to-carbon ratio; and the first heat exchanger 5 preheats the feedstock mixture using internal waste heat or an external heating source, increasing its temperature to reduce the energy consumption for starting up the subsequent diesel reforming reactor 6.

[0030] The steam generator 3 operates at a temperature between 300℃ and 400℃ and a pressure between 700 and 900 kPa to ensure that the water is completely vaporized and has sufficient enthalpy.

[0031] The diesel desulfurizer 16 can be an adsorption-type desulfurization device, filled with desulfurizing agents such as zinc oxide, molecular sieve or supported metal oxide (such as NiO / Al2O3), and operates at a temperature between 300℃ and 380℃. It can effectively remove thiophene and benzothiophene organic sulfur compounds from diesel fuel, reducing the total sulfur content to below 1 ppm.

[0032] Mixer 4 comprises a series combination of a T-type micro-mixer 4 and a static mixer 4. The former enables rapid initial mixing, while the latter promotes fluid shearing and diffusion through internal twisted blades, thereby obtaining a highly homogeneous gas-phase mixture. During the mixing process, the water-to-carbon ratio (H2O / C) is controlled within the range of 3.5-5.5, and can be optionally set to 4.5, to balance hydrogen yield and carbon deposition risk.

[0033] In an alternative embodiment, the mixer 4 may employ a venturi injection structure, which uses high-speed water vapor to entrain diesel vapor for mixing, requiring no additional power drive, and is compact and responsive.

[0034] The first heat exchanger 5 is a shell-and-tube or plate heat exchanger, with the diesel and steam mixture flowing through its cold fluid side. The heat source can be the high-temperature gas from the outlet of the diesel reforming reactor 6, the exhaust heat from the PEMFC stack 13, or an external electric heating system. This heat exchanger preheats the feed mixture to above 600°C (e.g., 750°C), close to the starting temperature required for the reforming reaction, significantly reducing the temperature rise load on the diesel reforming reactor 6.

[0035] In some embodiments of the present invention, the power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell further includes a second heat exchanger 7; the outlet of the diesel reforming reactor 6 is connected to the hot fluid inlet of the second heat exchanger 7, and the hot fluid outlet of the second heat exchanger 7 is connected to the inlet of the water gas reactor.

[0036] The diesel reforming reactor 6 is used to perform an endothermic reaction between diesel fuel and steam at high temperatures, generating a first gas mixture rich in hydrogen and carbon monoxide. The reaction temperature is typically above 700°C, and the exhaust gas has high thermal energy. If this high-temperature first gas mixture is directly introduced into the water-gas reactor, it may exceed the catalyst's suitable operating temperature range, which is particularly detrimental to the reaction equilibrium in the low-temperature water-gas shift (LT-WGS) stage and can easily lead to thermal stress concentration in the equipment materials, affecting system stability and lifespan. Therefore, effective cooling treatment of the reformed gas is necessary.

[0037] By adding a second heat exchanger 7 between the diesel reforming reactor 6 and the water gas reactor, the temperature of the high-temperature first mixed gas can be controlled. The high-temperature first mixed gas generated by the diesel reforming reactor 6 passes through the second heat exchanger 7, where it releases some heat and cools down before flowing out from the hot fluid outlet into the water gas reactor. This provides suitable feed conditions for the subsequent CO conversion reaction and avoids the adverse effects of high temperature on downstream catalysts and equipment.

[0038] In another alternative embodiment, the outlet of the diesel reforming reactor 6 can be connected to the hot fluid inlet of the first heat exchanger 5, and the hot fluid outlet of the first heat exchanger 5 can be connected to the inlet of the water-gas reactor, such as... Figure 2 As shown, the first mixed gas at the outlet of the diesel reforming reactor 6 is used to preheat the feed gas mixture (a mixture of diesel vapor and water vapor), thereby reducing external heating energy consumption, improving overall thermal efficiency, and realizing effective cascade utilization of waste heat.

[0039] The water-gas reactor of the present invention can be configured as a single-stage or multi-stage reaction unit. Specifically, in some embodiments of the present invention, the water-gas reactor includes a first water-gas reactor 8 and a second water-gas reactor 9; the hot fluid outlet of the second heat exchanger 7 is connected to the inlet of the first water-gas reactor 8, the outlet of the first water-gas reactor 8 is connected to the inlet of the second water-gas reactor 9, and the outlet of the second water-gas reactor 9 is connected to the inlet of the palladium membrane reactor 10.

[0040] More specifically, a heat exchanger is provided between the first water gas reactor 8 and the second water gas reactor 9. The outlet of the first water gas reactor 8 is connected to the hot fluid inlet of the heat exchanger, and the hot fluid outlet of the heat exchanger is connected to the inlet of the second water gas reactor 9.

[0041] This invention employs a first water-gas reactor 8 and a second water-gas reactor 9 arranged in series to achieve efficient gradient conversion of carbon monoxide in the first mixed gas, maximizing hydrogen yield, thereby improving hydrogen purity and reducing the operating load of the subsequent palladium membrane separation unit. The first water-gas reactor 8 receives the high-temperature first mixed gas cooled by the second heat exchanger 7 and performs a high-temperature water-gas shift reaction (HT-WGS) under the action of a suitable catalyst. The operating temperature range is set between 350°C and 450°C, optionally 400°C. Within this temperature range, the reaction rate is relatively fast, rapidly converting most of the CO into CO2 and H2. The gas exiting the first water-gas reactor 8 contains residual CO and requires further treatment to meet the PEMFC stack 13's requirement that the CO concentration in the hydrogen be below 10 ppm. Therefore, the outlet of the first water-gas reactor 8 is connected to the inlet of the second water-gas reactor 9, allowing the gas to enter the low-temperature water-gas shift stage (LT-WGS). Before entering the second water-gas reactor 9, the gas is further cooled to 200°C to 260°C (selectably 240°C) via an additional heat exchanger to facilitate a shift in the thermodynamic equilibrium of the low-temperature water-gas shift reaction towards the product side. This invention achieves efficient, staged removal of carbon monoxide from diesel steam reforming product gas. By employing a two-stage water-gas shift path combining high and low temperatures, the high-temperature stage ensures rapid conversion in the initial reaction phase, while the low-temperature stage achieves deep purification, resulting in a significant reduction in CO concentration in the mixed gas entering the palladium membrane reactor 10, thus improving system operational stability and hydrogen recovery rate.

[0042] In some embodiments of the present invention, a heater is provided between the second water-gas reactor 9 and the palladium membrane reactor 10. The second mixed gas exiting the second water-gas reactor 9 is heated to 350-500°C by the heater and then transported to the palladium membrane reactor 10. After the temperature increases, the diffusion coefficient of hydrogen atoms in palladium increases significantly, and hydrogen embrittlement can be avoided, preventing the palladium membrane from rupturing.

[0043] In some embodiments of the present invention, the power generation system of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell further includes a third heat exchanger 11, the hydrogen outlet of the palladium membrane reactor 10 is connected to the hot fluid inlet of the third heat exchanger 11, and the hot fluid outlet of the third heat exchanger 11 is connected to the anode inlet of the PEMFC stack 13.

[0044] A third heat exchanger 11 is installed between the palladium membrane reactor 10 and the PEMFC stack 13 to cool the high-temperature hydrogen gas, ensuring it meets the temperature requirements of the anode inlet gas of the PEMFC stack 13. The third heat exchanger 11 operates in a temperature range of 300℃ to 450℃, with a design pressure of no less than 800 kPa. After cooling, the hydrogen gas temperature can be reduced to 60-80℃, with 70℃ being a selectable option. This meets the temperature window required for the normal operation of the PEMFC stack 13, preventing thermal damage to the membrane modules in the PEMFC stack 13 and ensuring the stability and safety of the operation of the PEMFC stack 13.

[0045] In some embodiments of the present invention, a humidity control unit can be integrated in the connection path between the third heat exchanger 11 and the palladium membrane reactor 10 to moderately humidify the hydrogen (e.g., relative humidity 2%-3%), thereby further improving the proton conduction capability of the battery membrane in the PEMFC stack 13.

[0046] In some embodiments of the present invention, the power generation system of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell further includes a buffer tank 12, the hot fluid outlet of the third heat exchanger 11 is connected to the inlet of the buffer tank 12, and the outlet of the buffer tank 12 is connected to the anode inlet of the PEMFC stack 13.

[0047] By setting up buffer tank 12 as an intermediate energy storage unit, the problem of hydrogen flow and pressure fluctuation caused by the instability of the upstream hydrogen production process is solved, thereby ensuring stable gas intake conditions on the anode side of PEMFC stack 13.

[0048] In some embodiments of the present invention, the power generation system of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell further includes a condenser 14; the exhaust gas outlet of the palladium membrane reactor 10 is connected to the inlet of the condenser 14, the gas outlet of the condenser 14 outputs gas, and the liquid outlet of the condenser 14 outputs water.

[0049] The condenser 14 is used to cool the high-temperature exhaust gas discharged from the palladium membrane reactor 10, achieving gas-liquid two-phase separation. This exhaust gas mainly contains non-condensable gases that do not permeate the palladium membrane (such as CO, CO2, CH4, etc.) and water vapor. When the exhaust gas enters the condenser 14 from the exhaust outlet of the palladium membrane reactor 10, its temperature drops below the dew point due to heat exchange, causing the water vapor to undergo a phase change and condense into liquid water, which is then discharged from the system or reused through the liquid outlet of the condenser 14. The non-condensable gas components are discharged as waste gas from the gas outlet and can be used for subsequent combustion heating, pre-emission purification, or energy recovery.

[0050] The method for generating electricity using a diesel reforming-coupled proton exchange membrane fuel cell according to the present invention includes: S1, diesel and water vapor are mixed and reformed to produce the first mixture; S2, the first mixture is subjected to a water-gas shift reaction to obtain the second mixture; S3, the second mixed gas is separated by a palladium membrane, and the separated hydrogen is sent to the PEMFC stack 13 for power generation.

[0051] This method provides a complete on-site hydrogen production-purification-power generation integrated process. Through multi-step synergistic processing, it achieves efficient conversion from conventional liquid fuels to high-purity hydrogen, which can then be directly used for fuel cell power generation.

[0052] In process S1, diesel fuel and high-temperature steam undergo an endothermic reforming reaction under the action of a catalyst, breaking down carbon chains and generating hydrogen-rich syngas (i.e., the first mixed gas), primarily composed of hydrogen and carbon monoxide. This process is typically carried out at a high temperature of 650–850°C. In process S2, the first mixed gas is introduced into a water-gas shift reactor, where CO further reacts with steam to generate H2 and CO2, thereby increasing hydrogen production and reducing CO concentration. This reaction is exothermic, and the degree of reaction can be controlled by adjusting the temperature in stages. For example, preliminary conversion can be carried out in a higher temperature range (e.g., 350–450°C), followed by deep conversion in a lower temperature range (e.g., 200–260°C), which helps to shift the reaction towards the product direction and further reduce residual CO content. In process S3, the second mixed gas, after water-gas shift treatment, is introduced into a palladium membrane reactor 10, where the high selective permeability of the palladium membrane to hydrogen enables gas separation. The separated high-purity hydrogen is then fed into the anode of the PEMFC stack 13 to participate in an electrochemical reaction, generating electrical energy output.

[0053] In some embodiments of the present invention, S3 specifically involves heating the second mixed gas to 350-500°C, optionally 400°C, and then separating it through a palladium membrane. The separated hydrogen gas is then sent to a PEMFC for power generation.

[0054] Specifically, in one embodiment of the present invention, the power generation method of the diesel reforming hydrogen-coupled proton exchange membrane fuel cell includes the following steps: Step 1: Raw material pretreatment and precise supply.

[0055] Step 1.1: Diesel fuel supply and vaporization. Diesel fuel is drawn using the first metering pump 1, heated to 350°C for desulfurization, and then vaporized and pressurized to 800 kPa. Step 1.2: Water supply and steam generation. Deionized water is drawn using the second metering pump 2 and converted into steam at 350°C and 800 kPa using the steam generator 3; Step 1.3: Mixing and homogenization. The water-to-carbon ratio is 4.5. A combination of a T-type micro-mixer 4 and a static mixer 4 is used to ensure that the diesel vapor and water vapor are fully mixed. The mixing temperature is 350℃.

[0056] Step 2: Steam reforming reaction.

[0057] Step 2.1: After heating the raw material mixture to 750°C using the first heat exchanger 5, it is introduced into the diesel reforming reactor 6. Since the reaction is endothermic, the diesel reforming reactor 6 is heated using an electric heating mantle with a temperature control accuracy of ±2°C. Step 2.2: Reaction conditions: reaction temperature 750℃, pressure 750 kPa, water-to-carbon ratio 4.5, volume hourly space velocity (GHSV) 3000 h⁻¹ -1 The reaction equation is: C 16 H 34 +16H2O→16CO+33H2(ΔH≈+2500 kJ / kg).

[0058] Step 3: Water-gas shift reaction.

[0059] Step 3.1: The first mixed gas at 750℃ is cooled to 400℃ using the second heat exchanger 7 to perform high-temperature water-gas shift (HT-WGS). The reaction equation is: CO + H₂O → CO₂ + H₂ (ΔH = 41kJ / mol); Step 3.2: Low temperature is conducive to the reaction proceeding in the direction of hydrogen production. The mixed gas that has passed through the high-temperature water-gas shift is cooled to 240°C through a heat exchanger, and then the low-temperature water-gas shift (LT-WGS) continues. Water vapor and carbon monoxide react to produce hydrogen and carbon dioxide, which further increases the hydrogen production and reduces the CO content, preventing palladium membrane poisoning.

[0060] Step 4: Hydrogen purification using palladium membrane.

[0061] Step 4.1: The diffusion coefficient of hydrogen atoms in palladium increases significantly with increasing temperature, and hydrogen embrittlement is avoided, preventing membrane rupture. The temperature of the second mixed gas is increased to 400℃ using a heater, and the pressure difference across the palladium membrane is 600 kPa. Hydrogen is separated through the palladium membrane reactor 10, leaving water vapor, carbon monoxide, carbon dioxide, and other gases. Step 4.2: Convert the remaining water vapor into liquid water in condenser 14; Step 4.3: Collect the condensed liquid water through the water storage tank 15 and discharge gases such as carbon monoxide and carbon dioxide.

[0062] Step 5: Hydrogen cooling, pressure stabilization and buffering.

[0063] Step 5.1: The temperature of the purified hydrogen is reduced from 400℃ to 70℃ through the third heat exchanger 11; Step 5.2: Store the purified hydrogen in buffer tank 12; Step 5.3: Use a pressure regulating valve to ensure stable pressure at the anode inlet of PEMFC stack 13.

[0064] Step 6: PEMFC power generation.

[0065] Step 6.1: Pass the hydrogen in buffer tank 12 and the oxygen in oxygen tank into PEMFC stack 13 to generate electricity; Step 6.2: Connect the load to the PEMFC stack 13 and use the PEMFC stack 13 to generate electricity for the load; Step 6.3: Discharge the water generated during power generation in the PEMFC stack 13.

[0066] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A power generation system for a diesel reforming-coupled proton exchange membrane fuel cell, characterized in that, include: The diesel reforming reactor (6), palladium membrane reactor (10), water gas reactor and PEMFC stack (13) are connected; the outlet of the diesel reforming reactor (6) is connected to the inlet of the water gas reactor, the outlet of the water gas reactor is connected to the inlet of the palladium membrane reactor (10), and the hydrogen outlet of the palladium membrane reactor (10) is connected to the anode inlet of the PEMFC stack (13).

2. The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell according to claim 1, characterized in that, It also includes a steam generator (3), a diesel desulfurizer (16), a mixer (4), and a first heat exchanger (5); the outlet of the steam generator (3) is connected to the first inlet of the mixer (4), the outlet of the diesel desulfurizer (16) is connected to the second inlet of the mixer (4), the outlet of the mixer (4) is connected to the cold fluid inlet of the first heat exchanger (5), and the cold fluid outlet of the first heat exchanger (5) is connected to the inlet of the diesel reforming reactor (6).

3. The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell according to claim 1, characterized in that, It also includes a second heat exchanger (7); the outlet of the diesel reforming reactor (6) is connected to the hot fluid inlet of the second heat exchanger (7), and the hot fluid outlet of the second heat exchanger (7) is connected to the inlet of the water gas reactor.

4. The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell according to claim 3, characterized in that, The water gas reactor includes a first water gas reactor (8) and a second water gas reactor (9); the hot fluid outlet of the second heat exchanger (7) is connected to the inlet of the first water gas reactor (8), the outlet of the first water gas reactor (8) is connected to the inlet of the second water gas reactor (9), and the outlet of the second water gas reactor (9) is connected to the inlet of the palladium membrane reactor (10).

5. The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell according to claim 1, characterized in that, It also includes a third heat exchanger (11), the hydrogen outlet of the palladium membrane reactor (10) is connected to the hot fluid inlet of the third heat exchanger (11), and the hot fluid outlet of the third heat exchanger (11) is connected to the anode inlet of the PEMFC stack (13).

6. The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell according to claim 5, characterized in that, It also includes a buffer tank (12), the hot fluid outlet of the third heat exchanger (11) is connected to the inlet of the buffer tank (12), and the outlet of the buffer tank (12) is connected to the anode inlet of the PEMFC stack (13).

7. The power generation system of the diesel reforming hydrogen production coupled proton exchange membrane fuel cell according to claim 1, characterized in that, It also includes a condenser (14); the tail gas outlet of the palladium membrane reactor (10) is connected to the inlet of the condenser (14), the gas outlet of the condenser (14) outputs gas, and the liquid outlet of the condenser (14) outputs water.

8. A method for generating electricity using a diesel reforming-coupled proton exchange membrane fuel cell, characterized in that, include: S1, diesel and water vapor are mixed and reformed to produce the first mixture; S2, the first mixture is subjected to a water-gas shift reaction to obtain the second mixture; S3, the second mixed gas is separated by a palladium membrane, and the separated hydrogen is sent to the PEMFC for power generation.

9. The power generation method of a diesel reforming hydrogen-coupled proton exchange membrane fuel cell according to claim 8, characterized in that, S2 specifically involves: first, subjecting the first mixed gas to a high-temperature water-gas shift reaction at 350-450℃ to obtain the product, and then subjecting it to a low-temperature water-gas shift reaction at 200-260℃ to obtain the second mixed gas.

10. The power generation method of a diesel reforming hydrogen-coupled proton exchange membrane fuel cell according to claim 9, characterized in that, S3 specifically involves heating the second mixed gas to 350-500℃, then separating it through a palladium membrane, and sending the separated hydrogen gas into a PEMFC for power generation.

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