An ammonia-hydrogen fuel cell power generation system

Abstract

This application discloses an ammonia-hydrogen fuel cell power generation system, including an ammonia storage device, a membrane reactor, an ejector, and a power generation device. The ammonia storage device is used to introduce ammonia gas into the membrane reactor. The membrane reactor has a first separation outlet and a second separation outlet, which are simultaneously connected to the ejector. Multiple pipes are arranged in the membrane reactor, with gaps between them. Ammonia decomposition catalyst is filled in the gaps between the pipes. A hydrogen-selective structure is covered on the pipes, with its two sides connected to the inlet of the membrane reactor and the first separation outlet, respectively. The ejector is connected to the power generation device; a portion of the gas in the ejector can enter the power generation device for power generation. This ammonia-hydrogen fuel cell system reduces the dependence on catalyst performance during ammonia decomposition, improves ammonia decomposition efficiency, saves energy consumption during power generation, and improves energy reuse efficiency.

Description

Technical Field

[0001] This invention relates to the field of clean energy equipment technology, specifically to an ammonia-hydrogen fuel cell power generation system using ammonia as fuel. Background Technology

[0002] Hydrogen is a clean secondary energy source with excellent characteristics such as high calorific value, good combustion performance, environmental friendliness, and recyclability. Its reaction with oxygen produces only water as a byproduct. However, hydrogen is flammable and explosive, and its low bulk density makes it difficult to store and transport, thus keeping the end-use cost of hydrogen energy consistently high. Ammonia, on the other hand, is stable, and its production process is mature, allowing for easy acquisition, transportation, and storage. Using ammonia as a carrier to obtain hydrogen through ammonia decomposition and coupling it with a hydrogen fuel cell has become an effective method for hydrogen energy utilization. However, existing ammonia decomposition fuel cell systems suffer from drawbacks such as large catalyst loading, large volume, and high reaction temperatures in the ammonia decomposition reactor, resulting in low energy utilization efficiency.

[0003] Chinese patent CN113451615A discloses a liquid ammonia cracking power generation system, including an ammonia decomposition furnace and a separator. The ammonia decomposition furnace includes an outer layer, an inner liner, and a buffer tank. The outer layer is a combustion chamber, the inner liner is located inside the outer layer, and the buffer tank is located above the inner liner and separated from the inner liner by a hydrogen permeable membrane. The outer layer, the inner liner, and the buffer tank are not interconnected. The inner liner is filled with an ammonia decomposition catalyst. A liquid ammonia delivery pipeline is connected to the inner liner, and the outlet of the buffer tank is connected to the inlet of the separator. The ammonia is divided into two parts by the separator, and the two parts are discharged from the two outlets of the separator. One part of the gas enters the anode of the fuel cell, and the other part is discharged through the outlet of the separator. The outlet of the separator is then connected to the gas inlet of the outer layer of the ammonia decomposition furnace. Liquid ammonia is heated and then enters an ammonia decomposition furnace for catalytic decomposition. Hydrogen passes through a hydrogen permeation membrane into a buffer tank, achieving hydrogen purification and separation while promoting the equilibrium of ammonia decomposition. Some hydrogen is oxidized to provide heat for ammonia decomposition, and some hydrogen enters the fuel cell to generate electricity. This improves the decomposition efficiency of ammonia and the utilization rate of hydrogen. However, during the decomposition process of this ammonia decomposition furnace, if the ammonia flow rate is high, the ammonia mainly concentrates in the front of the inner tank, resulting in low ammonia decomposition efficiency at the rear of the inner tank and a high dependence on catalyst performance. Furthermore, the fuel source of the fuel cell mainly comes from hydrogen decomposition of ammonia, which is a relatively single fuel source, resulting in low power generation efficiency and high requirements for ammonia decomposition efficiency and energy supply. Summary of the Invention

[0004] To address the shortcomings of existing ammonia cracking power generation systems, such as high requirements for catalyst performance and dosage, single fuel source, and high requirements for ammonia decomposition efficiency and energy supply during power generation, this paper proposes an ammonia-hydrogen fuel cell system with high ammonia decomposition efficiency, low catalytic cost and high efficiency, and low energy consumption during power generation.

[0005] The technical solution adopted by this invention to solve its technical problem is as follows: an ammonia-hydrogen fuel cell power generation system, including an ammonia storage device, a membrane reactor, an ejector, and a power generation device; the ammonia storage device is used to introduce ammonia gas into the membrane reactor; the membrane reactor is provided with a first separation outlet and a second separation outlet, which are simultaneously connected to the ejector; multiple pipes are provided in the membrane reactor, and gaps exist between the multiple pipes; the gaps between the multiple pipes are filled with an ammonia decomposition catalyst; the multiple pipes are covered with a hydrogen selective structure, and both sides of the hydrogen selective structure are connected to the inlet of the membrane reactor and the first separation outlet, respectively; the ejector is connected to the power generation device; a portion of the gas in the ejector can enter the power generation device for power generation.

[0006] Furthermore, a heating device is provided between the ammonia storage device and the membrane reactor. The heating device includes a vaporizer and a preheater that are connected to each other. The vaporizer is connected to the ammonia storage device, and the preheater is connected to the membrane reactor.

[0007] Furthermore, the membrane reactor has an inlet for introducing ammonia gas, which communicates with the chamber of the membrane reactor. A first baffle is fixed inside the chamber of the membrane reactor and is fixed to the inner wall of the chamber. There are gaps between multiple pipes. One end of the pipe is a closed structure and the other end of the pipe is an open structure. The open end of each pipe is fixed to the side of the first baffle facing the inlet, and each pipe extends towards the inlet.

[0008] Furthermore, the other side of the first partition is the ejection area, in which multiple ejection devices and a second partition are arranged. The second partition is fixed to the inner wall of the ejection area. There are gaps between the multiple ejection devices. The multiple ejection devices are fixed to the side of the second partition facing the first partition. There are equal gaps between the multiple ejection devices. The end of each ejection device away from the second partition passes through the first partition and extends into the cavity. Each ejection device communicates with the cavity.

[0009] Furthermore, the ejector device includes a first ejector section and a second ejector section that communicate with each other. The cross-sectional area of ​​the first ejector section is larger than that of the second ejector section. The second ejector section extends into the interior of the first ejector section. There is a gap between the second ejector section and the first ejector section. The gap between the second ejector section and the first ejector section communicates with the ejection area. One end of the first ejector section away from the second ejector section is fixed to the second partition plate. The other end of the second ejector section away from the first ejector section passes through the first partition plate and communicates with the chamber. The ends of the multiple ejector devices connected to the second partition plate are simultaneously connected to the first separation outlet.

[0010] Furthermore, the membrane reactor is also connected to a heating mechanism, and the material used to manufacture the hydrogen selective structure is a metal oxide or a polymer; the ammonia decomposition catalyst is a ruthenium-based catalyst or a nickel-based catalyst.

[0011] Furthermore, the gas pressure of the gas discharged from the second separation outlet and entering the ejector is greater than the gas pressure of the gas discharged from the first separation outlet and entering the ejector.

[0012] Furthermore, it also includes a desorption device and a combustion device. The ejector outlet is connected to the desorption device, one outlet of the desorption device is connected to the power generation device, and the other outlet of the desorption device is connected to the combustion device.

[0013] Furthermore, the cathode outlet and anode outlet of the power generation device are simultaneously connected to the combustion device, and the gas discharged from the power generation device after reaction can enter the combustion device for further combustion; a gas pipe is wound around the outer wall of the membrane reactor, and the outlet end of the power generation device is connected to the gas pipe on the outer wall of the membrane reactor; the power generation device is also electrically connected to the air compression device.

[0014] Furthermore, it also includes a heat exchanger, a regenerator, a turbine, and a combustion device; the outlet of the ejector is connected to the combustion device, the outlet of the combustion device is connected to the turbine, and the turbine is connected to the power generation device; the turbine is also connected to the heat exchanger, the outlet of the heat exchanger is connected to the regenerator, one outlet of the regenerator is connected to the combustion device, and the other outlet of the regenerator is connected to the outside air; the regenerator can use the heat of the gas discharged from the heat exchanger to heat the air, and reintroduce the heated air into the combustion device; the heat exchanger is thermally connected to the membrane reactor.

[0015] The ammonia-hydrogen fuel cell power generation system of this invention employs a membrane separation reactor containing a hydrogen selective membrane and multiple pipes. During ammonia decomposition, the ammonia decomposition efficiency is adjusted by controlling the hydrogen concentration, reducing the catalyst requirement and improving the efficiency. The mixed gas after ammonia decomposition is fed into an ejector, where the decomposed gas and hydrogen are mixed. The increased hydrogen pressure meets the inlet pressure requirements of the fuel cell, saving compression power consumption and improving energy efficiency. Simultaneously, the gas generated by the power generation device is re-burned, and the heat from the combustion is used to heat the membrane reactor, achieving energy recycling within the system and reducing overall system energy consumption. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments 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 from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an ammonia-hydrogen fuel cell system according to the present invention;

[0018] Figure 2 This is a schematic diagram of the structure of the membrane reactor of an ammonia-hydrogen fuel cell system according to the present invention;

[0019] Figure 3 This is a cross-sectional view of the internal structure of the membrane reactor in an ammonia-hydrogen fuel cell system according to the present invention.

[0020] Figure 4 for Figure 3 A magnified view of a portion of the image;

[0021] Figure 5 This is a schematic diagram of another ammonia-hydrogen fuel cell system according to the present invention. Detailed Implementation

[0022] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0023] like Figures 1-5 As shown, the ammonia-hydrogen fuel cell power generation system of the present invention includes an ammonia storage device 1, a membrane reactor 2, an ejector 3, and a power generation device 5.

[0024] The ammonia storage device 1 is used to introduce ammonia gas into the membrane reactor 3;

[0025] The membrane reactor 2 is provided with a first separation outlet 21 and a second separation outlet 22, which are connected to the ejector 3. The membrane reactor 2 is provided with a plurality of pipes 211, and there are gaps between the plurality of pipes 211. The gaps between the plurality of pipes are filled with ammonia decomposition catalyst. The plurality of pipes 211 are covered with hydrogen selective structures 2110, and the two sides of the hydrogen selective structures 2110 are connected to the inlet 20 and the first separation outlet 21 of the membrane reactor 2, respectively.

[0026] The ejector 3 is connected to the power generation device 5; a portion of the gas in the ejector 3 can enter the power generation device 5 for power generation; the gas discharged from the ejector 3 and entering the power generation device 5 for power generation is a mixture of hydrogen and nitrogen.

[0027] This ammonia-hydrogen fuel cell system employs a membrane reactor 2 containing a hydrogen selective structure 2110 and multiple pipes 211. The combined effect of the pressure difference between the hydrogen selective structure 2110 and different regions within the membrane reactor effectively improves the catalytic efficiency during ammonia decomposition and reduces the requirements for catalyst performance and temperature during ammonia decomposition. By simultaneously connecting the two separation outlets of the membrane reactor 2 to an ejector 3, the pressure of the gas entering the ejector 3 from the different separation outlets of the membrane reactor 2 is adjusted, thereby promoting the hydrogen decomposition rate in the membrane reactor 2 and improving the hydrogen production efficiency. Furthermore, by desorbing the gas discharged from the ejector 3, the desorbed gas is fed into power generation devices, such as fuel cells, and combustion devices as fuel. This allows for better utilization of the heat generated by the gas in the ammonia-hydrogen fuel cell system, improving the overall energy utilization rate of the system and reducing energy consumption during power generation and ammonia decomposition.

[0028] exist Figure 1 In this process, a heating device 10 is provided between the ammonia storage device 1 and the membrane reactor 2 to heat the liquid ammonia introduced from the ammonia storage device 1 into the membrane reactor 2. By preheating the liquid ammonia, the temperature required for ammonia decomposition is reached and it is suitable for the catalytic decomposition of the membrane reactor 2, thereby reducing the energy consumption of the membrane reactor 2. Specifically, the heating device 10 includes a vaporizer 101 and a preheater 102 connected together. The vaporizer 101 is used to vaporize the liquid ammonia in the ammonia storage device 1 into ammonia gas, and the preheater 102 is used to heat the vaporized ammonia gas to 20°C. Above 0℃, by separating vaporization and heating, liquid ammonia can be fully vaporized and heated; the vaporizer 101 is connected to the ammonia storage device 1, and the preheater 102 is connected to the membrane reactor 2. Liquid ammonia discharged from the ammonia storage device 1 enters the vaporizer 101 and is first heated and vaporized to generate ammonia gas. The generated ammonia gas then enters the preheater 102 for further heating to reach the temperature required for ammonia decomposition. The ammonia gas heated by the preheater 102 enters the membrane reactor 2 connected to the preheater 102 for further ammonia decomposition reaction.

[0029] like Figures 2-4As shown, the membrane reactor 2 is provided with an inlet 20, a first separation outlet 21, and a second separation outlet 22. The inlet 20 communicates with the chamber 201 of the membrane reactor 2. Multiple pipes 211 are arranged inside the chamber 201 of the membrane reactor 2. A first partition 221 is fixed inside the chamber 201 of the membrane reactor 2, and the first partition 221 is fixed to the inner wall of the chamber 201 of the membrane reactor 2. One end of each of the multiple pipes 211 is fixed to the side of the first partition 221 facing the inlet 20 and close to the inlet 20. The direction of the extension is set; wherein, a plurality of the pipes 211 are arranged parallel to each other, and the plurality of pipes 211 are vertically fixed to the first partition plate 221; one end of the pipe 211 is a closed structure, and the opposite end of the pipe 211 is an open structure, wherein the open end of the pipe 211 is fixed to the first partition plate 221; gaps are provided between the plurality of pipes 211, and the gaps between any two pipes 211 are equal; in order to improve the decomposition efficiency of ammonia introduced from the inlet 20, the chamber 201 The interior, particularly the gaps between the plurality of pipes 211, is filled with an ammonia decomposition catalyst, such as a ruthenium-based catalyst or a nickel-based catalyst. Further, the other side of the first partition 221 is an ejector region 23, within which a plurality of ejector devices 223 and a second partition 222 are disposed. The second partition 222 is fixed to the inner wall of the ejector region 23, and the plurality of ejector devices 223 are fixed to the side of the second partition 222 facing the first partition 221. Gaps exist between the plurality of ejector devices 223. The ejector device 223 is vertically fixed on the second partition 222 and is arranged facing the side closer to the first partition 221. The plurality of ejector devices 223 are arranged parallel to each other, and there are equal gaps between the plurality of ejector devices 223. In order to adjust the air pressure inside the chamber 201 and promote gas flow, specifically, the end of each ejector device 223 away from the second partition 222 passes through the first partition 21 and extends into the chamber 201, and each ejector device 223 communicates with the chamber 201.The ejector device 223 includes a first ejector portion 2231 and a second ejector portion 2232 that communicate with each other. The cross-sectional area of ​​the first ejector portion 2231 is larger than that of the second ejector portion 2232. The second ejector portion 2232 extends into the interior of the first ejector portion 2231. There is a gap between the second ejector portion 2232 and the first ejector portion 2231. The gap between the second ejector portion 2232 and the first ejector portion 2231 communicates with the ejection region 23. One end of the first ejector portion 2231 away from the second ejector portion 2232 is vertically fixed to the second partition 222. Above, one end of the second ejector 2232, away from the first ejector 2231, passes through the first partition 221 and communicates with the chamber 201; more specifically, one end of each of the multiple ejector devices 223 connected to the second partition 222 is simultaneously connected to the first separation outlet 21, allowing the decomposed ammonia gas to be discharged through one end of each of the multiple ejector devices 223, and finally discharged from the membrane reactor 2 through the first separation outlet 21; by employing multiple ejectors with the above structure, the pressure of the gas in the membrane reactor 2 can be evenly distributed, which is beneficial for reducing energy consumption during subsequent compression.

[0030] To achieve the separation of hydrogen and nitrogen in the decomposed mixed gas and improve the purity of hydrogen in the mixed gas discharged from the membrane reactor 2, specifically, a hydrogen selective structure 2110 with a corresponding shape is provided on the pipe 211. The hydrogen selective membrane 2110 is used to separate hydrogen in the decomposed mixed gas, allowing hydrogen in the decomposed mixed gas to pass through the hydrogen selective structure 2110 and enter the pipe 211. The hydrogen entering the pipe 211 is discharged from the pipe 211 through one end of the open structure of the pipe 211 and enters the ejector region 23. The first ejector part 2231 and the second ejector part of the ejector device 223... There is a gap between the ejector sections 2232, and the gap between the first ejector section 2231 and the second ejector section 2232 communicates with the ejector region 23. The hydrogen enters the pipe 211 through the hydrogen selective structure 2110, and the hydrogen discharged from the pipe 211, after entering the ejector region 23, can enter the gap between the first ejector section 2231 and the second ejector section 2232, and is discharged from the ejector device 223 through the second ejector section 2232. The discharged hydrogen is discharged from the membrane reactor 2 through the first separation outlet 21 connected to the ejector device 223. More specifically, the hydrogen selective structure is made of metal oxide or polymer.

[0031] To adjust the gas pressure inside chamber 201 during ammonia decomposition and control the ammonia decomposition rate and gas flow rate in membrane reactor 2, preferably, chamber 201 is connected to the second separation outlet 22. The gas pressure inside chamber 201 is adjusted by adjusting the opening of the second separation outlet 22, and the ammonia decomposition rate and flow rate are adjusted by adjusting the amount of gas inside chamber 201. To better promote ammonia decomposition and ensure that ammonia is fully decomposed in chamber 201 to generate a mixed gas containing hydrogen and nitrogen, specifically, chamber 201 of membrane reactor 2 is also connected to a heating mechanism (not shown). This heating mechanism heats the ammonia located in chamber 201, working together with the ammonia decomposition catalyst in chamber 201 to promote the ammonia decomposition reaction.

[0032] When the heated and vaporized ammonia gas enters the chamber 201 through the inlet 20, the ammonia gas flows towards the plurality of pipes 211. Under the action of the ammonia decomposition catalyst and heating device filled in the chamber 201, the ammonia gas is heated and decomposed to generate a mixed gas of hydrogen and nitrogen, and continues to flow towards the first separation outlet 21. Since each pipe 211 is provided with a hydrogen selective structure 2110, the hydrogen in the mixed gas passes through the hydrogen selective structure 2110 of each pipe 211 during the gas flow. Structure 2110 enters the pipe 211. Under the combined action of the hydrogen selective structure 2110 and the pressure difference between the inside and outside of the pipe 211, hydrogen continuously enters the pipe 211. The hydrogen entering the pipe 211 flows along the corresponding extension direction of the pipe 211 and enters the ejector region 23. Subsequently, it enters the second ejector part 2232 through the gap between the first ejector part 2231 and the second ejector part 2232 of the ejector device 223 in the ejector region 23, and finally flows along the... The second ejector section 2232 exits the membrane reactor 2 from the first separation outlet 21. During the flow process, as the vaporized ammonia continuously enters the chamber 201 and the decomposed gas exits through the first separation outlet 21 which is opposite to the chamber 201, the gas pressure in the chamber 201 is greater than the gas pressure in the ejector region 23. This allows the gas to continuously flow towards and enter the ejector region 23. Combined with the selective effect of the hydrogen selective structure 2110, the hydrogen in the decomposed gas continuously flows towards the ejector region 23 and exits through the first separation outlet 21. The hydrogen concentration in the ejector region 23 is lower than that in the pipe 211. Since the ammonia decomposition reaction is a reversible reaction, the low hydrogen concentration in the product is beneficial to the ammonia decomposition reaction, thus improving the catalytic efficiency of the catalyst located in the chamber 201, making the ammonia decomposition more complete and thorough. Therefore, the membrane reactor 2 reduces the amount of catalyst used during the ammonia decomposition process, reducing the catalyst usage cost.

[0033] like Figure 1As shown, the first separation outlet 21 and the second separation outlet 22 of the membrane reactor 2 are simultaneously connected to different inlets of the ejector 3. Specifically, the first separation outlet 21 is connected to the first ejector inlet 31 of the ejector 3, and the second separation outlet 22 is connected to the second ejector inlet 32 ​​of the ejector 3. Preferably, in order to ensure that hydrogen and nitrogen from the membrane reactor 2 can fully and completely enter the ejector 3 and sequentially enter the subsequent desorption device 4 and power generation device 5 through the ejector 3, the pressure of the nitrogen gas discharged through the second separation outlet 22 into the ejector 3 is greater than that of the nitrogen gas entering the ejector 3. The hydrogen gas discharged from the first separation outlet 21 and entering the ejector 3 has a lower pressure. The nitrogen gas, with a higher pressure, discharged from the second separation outlet 22, flows rapidly into the ejector 3, creating a low-pressure region within it. This accelerates the entry of the hydrogen gas from the first separation outlet 21 into the ejector 3, causing the separated hydrogen gas from the multiple pipes 211 of the membrane reactor 2 to enter the ejector 3 more completely through the first separation outlet 21. The hydrogen gas discharged from the first separation outlet 21 mixes with the nitrogen gas discharged from the second separation outlet 22 and then enters the ejector 3 in a concentrated manner. Centralized desorption occurs in the desorption device 4; more specifically, the desorption device 4 is a temperature-switching adsorption device, and the desorption effect of the desorption device 4 on residual ammonia in the mixed gas is adjusted by adjusting the temperature in the desorption device 4; wherein, the desorption device 4 includes a first desorption outlet 41 and a second desorption outlet 42, the first desorption outlet 41 is connected to the combustion device 6, and the second desorption outlet 42 is connected to the anode inlet of the power generation device 5. Since the hydrogen and nitrogen gas after reaction and decomposition in the membrane reactor 2, as well as the residual undecomposed ammonia gas, all enter the ejector 3 through the corresponding separation outlets for mixing, Furthermore, the mixed hydrogen, nitrogen, and a small amount of ammonia are all introduced into the desorption device 4 through the ejector 3. After being desorbed by the desorption device 4, the hydrogen and nitrogen are simultaneously introduced into the anode inlet of the power generation device 5 to provide fuel for the power generation device 5. Compared with simply introducing hydrogen into the power generation device 5 for power generation, by mixing hydrogen and nitrogen and simultaneously introducing them into the anode of the power generation device 5, the pressure of hydrogen can be increased to meet the inlet pressure requirements of the fuel cell, saving compression power consumption and improving energy efficiency. The ammonia after being desorbed by the desorption device 4 enters the combustion device 6 as fuel for the combustion device 6.

[0034] To better utilize the energy from the desorption device 4 and the exhaust gas discharged from the power generation device 5, and to improve the energy utilization rate of the ammonia-hydrogen fuel cell system while reducing energy consumption, preferably, the ammonia-hydrogen fuel cell system further includes a combustion device 6. The combustion inlet of the combustion device 6 is connected to the anode outlet and cathode outlet of the desorption device 4 and the power generation device 5, respectively. A gas pipe (not shown) is wound around the outer wall of the membrane reactor 2, and the combustion outlet of the combustion device 6 is connected to the gas pipe on the outer wall of the membrane reactor 2. Specifically, the ammonia gas desorbed from the desorption device 4 and the exhaust gas discharged from the power generation device 5 are used to generate the ammonia-hydrogen fuel cell. The remaining gas after the reaction and power generation in device 5 is introduced into the combustion device 6. The combustion device 6 mixes and burns the ammonia introduced from the desorption device 4 and the tail gas discharged from the anode and cathode outlets of the power generation device 5 to generate heated gas with a higher temperature. The generated gas is discharged from the combustion device 6 and enters the membrane reactor 2 connected to it, providing heat for the operation of the membrane reactor 2, promoting the decomposition reaction of ammonia in the membrane reactor 2, increasing the hydrogen content discharged from the membrane reactor 2, thereby improving the energy utilization rate of the entire system and the decomposition efficiency of ammonia in the membrane reactor 2.

[0035] To better utilize the heat generated by the combustion gas in the combustion device 6, preferably, the membrane reactor 2 is thermally connected to the preheater 102, and the preheater 102 is thermally connected to the vaporizer 101. After the gas is burned by the combustion device 6, it enters the membrane reactor 2 for heating. The heat from the gas burned by the combustion device 6 can be sequentially transferred from the membrane reactor 2 to the preheater 102 and the vaporizer 101 to provide heat for the preheater 102 and the vaporizer 101 to heat the liquid ammonia, thereby reducing the energy consumption of the preheater 102 and the vaporizer 101 and improving the energy recycling rate of the entire system.

[0036] The power generation device 5 is a fuel cell, such as a hydrogen fuel cell. The cathode inlet of the power generation device 5 is connected to the air compression device 7. The power generation device 5 can convert the chemical energy of air introduced from the air compression device 7 and the hydrogen and nitrogen mixture desorbed from the desorption device 4 into electrical energy. The exhaust gas after conversion is discharged from the power generation device 5 through the cathode outlet and anode outlet, respectively, and enters the combustion device 6 for combustion, realizing the reuse of exhaust gas energy. The exhaust gas after combustion is then reintroduced into the membrane reactor. The heat exchanger 2 is used to provide heat for the decomposition of ammonia in the membrane reactor 2. After the exhaust gas from the combustion process is heated, it continues to pass sequentially through the preheater 102 and the vaporizer 101, which are thermally connected to the membrane reactor 2, to further provide energy for the vaporization and preheating of liquid ammonia, thereby realizing the reuse of exhaust gas heat. Preferably, the power generation device 5 and the air compression device 7 are electrically connected, and the electrical energy generated by the power generation device 5 can be transferred to the air compression device 7 and provide electrical energy to the air compression device 7, thus also realizing the reuse of energy.

[0037] exist Figure 5 In this process, the first separation outlet 21 and the second separation outlet 22 of the membrane reactor 2 are simultaneously connected to the ejector 3. The outlet of the ejector 3 is directly connected to the combustion device 6. The ejector 3 can mix the gas introduced from the membrane reactor 2 and introduce the mixed gas into the combustion device 6 for combustion. To better utilize the energy of the gas introduced from the ejector 3, specifically, the outlet of the combustion device 6 is connected to a turbine 81. The turbine 81 can transfer the energy of the exhaust gas discharged from the combustion device 6 into mechanical energy, and drive the motor 82 connected to the turbine 81 to rotate and generate electrical energy. At the same time, the outlet end of the turbine 81 is connected to a heat exchanger 83, which is also thermally connected to the membrane reactor 2. The heat exchanger 83 can transfer the energy of the exhaust gas discharged from the membrane reactor 2 into mechanical energy, and drive the motor 82 connected to the turbine 81 to rotate and generate electrical energy. The heat discharged from turbine 81 after the reaction is transferred to membrane reactor 2 to provide heat for the decomposition of ammonia in membrane reactor 2. The outlet of heat exchanger 83 is connected to the inlet of regenerator 84, which is also connected to air compressor 85. Air compressor 85 is used to introduce air into regenerator 84. Since the inlet of regenerator 84 is connected to heat exchanger 83, the gas introduced from heat exchanger 83 after combustion in combustion device 6 can continue to be used to heat the air introduced from air compressor 85. The air heated by regenerator 84 is then introduced back into combustion device 6 to provide fuel for combustion of mixed gas in combustion device 6, reducing the heat required for combustion in combustion device 6 and improving the combustion efficiency of combustion device 6.

[0038] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An ammonia-hydrogen fuel cell power generation system, comprising an ammonia storage device, a membrane reactor, an ejector, and a power generation device; characterized in that: The ammonia storage device is used to introduce ammonia gas into the membrane reactor; The membrane reactor is provided with a first separation outlet and a second separation outlet, which are connected to the ejector. The membrane reactor is provided with multiple pipes with gaps between them. The gaps between the multiple pipes are filled with an ammonia decomposition catalyst. The multiple pipes are covered with a hydrogen selective structure, which is connected to the inlet and the first separation outlet of the membrane reactor on both sides. The membrane reactor also has an inlet for introducing ammonia gas, which communicates with the chamber of the membrane reactor. A first partition is fixed inside the chamber of the membrane reactor and is fixed to the inner wall of the chamber. There are gaps between the multiple pipes. One end of each pipe is closed and the other end is open. The open end of each pipe is fixed to the side of the first partition facing the inlet. Each pipe extends towards the inlet. The other side of the first partition is an ejection area, in which multiple ejection devices and a second partition are arranged. The second partition is fixed to the inner wall of the ejection area. There are gaps between the multiple ejection devices. The multiple ejection devices are fixed on the side of the second partition facing the first partition. There are equal gaps between the multiple ejection devices. The end of each ejection device away from the second partition passes through the first partition and extends into the cavity. Each ejection device communicates with the cavity. The membrane reactor is also connected to a heating mechanism; the material used to manufacture the hydrogen selective structure is a metal oxide or a polymer; the ammonia decomposition catalyst is a ruthenium-based catalyst or a nickel-based catalyst. The ejector is connected to the power generation device; a portion of the gas in the ejector can enter the power generation device for power generation; the gas discharged from the ejector and entering the power generation device for power generation is a mixture of hydrogen and nitrogen.

2. The ammonia-hydrogen fuel cell power generation system according to claim 1, characterized in that: A heating device is provided between the ammonia storage device and the membrane reactor. The heating device includes a vaporizer and a preheater that are connected to each other. The vaporizer is connected to the ammonia storage device, and the preheater is connected to the membrane reactor.

3. The ammonia-hydrogen fuel cell power generation system according to claim 1, characterized in that: The ejector device includes a first ejector section and a second ejector section that communicate with each other. The cross-sectional area of ​​the first ejector section is larger than that of the second ejector section. The second ejector section extends into the interior of the first ejector section. There is a gap between the second ejector section and the first ejector section. The gap between the second ejector section and the first ejector section communicates with the ejection area. One end of the first ejector section away from the second ejector section is fixed to the second partition plate. The other end of the second ejector section away from the first ejector section passes through the first partition plate and communicates with the chamber. One end of the plurality of ejector devices connected to the second partition plate is simultaneously connected to the first separation outlet.

4. The ammonia-hydrogen fuel cell power generation system according to claim 1, characterized in that: The gas pressure of the gas exiting from the second separation outlet and entering the ejector is greater than the gas pressure of the gas exiting from the first separation outlet and entering the ejector.

5. The ammonia-hydrogen fuel cell power generation system according to claim 1, characterized in that: It also includes a desorption device and a combustion device. The outlet of the ejector is connected to the desorption device, one outlet of the desorption device is connected to the power generation device, and the other outlet of the desorption device is connected to the combustion device.

6. The ammonia-hydrogen fuel cell power generation system according to claim 5, characterized in that: The cathode outlet and anode outlet of the power generation device are simultaneously connected to the combustion device, and the gas discharged from the power generation device after reaction can enter the combustion device for further combustion; a gas pipe is wound around the outer wall of the membrane reactor, and the outlet end of the power generation device is connected to the gas pipe on the outer wall of the membrane reactor; the power generation device is also electrically connected to an air compressor.

7. The ammonia-hydrogen fuel cell power generation system according to claim 1, characterized in that: It also includes a heat exchanger, a regenerator, a turbine, and a combustion device; the outlet of the ejector is connected to the combustion device, the outlet of the combustion device is connected to the turbine, and the turbine is connected to the power generation device; the turbine is also connected to the heat exchanger, the outlet of the heat exchanger is connected to the regenerator, one outlet of the regenerator is connected to the combustion device, and the other outlet of the regenerator is connected to the outside air; the regenerator can use the heat of the gas discharged from the heat exchanger to heat the air and reintroduce the heated air into the combustion device. The heat exchanger is thermally connected to the membrane reactor.

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