Hydrogen production unit of fuel cell stack, combined cooling heating and power system and combined cooling heating and power method

Abstract

The invention relates to a hydrogen production unit of a fuel cell stack and a combined cooling heating and power system and method.The hydrogen production unit comprises an aluminum water hydrogen production part which comprises an aluminum water reactor and a solid-gas separator; the aluminum water reactor is used for aluminum water reaction for hydrogen production; the solid-gas separator is connected with the aluminum water reactor and is used for separating hydrogen; the dehydrogenation part comprises a dehydrogenation reactor and a gas-liquid separator; the dehydrogenation reactor is used for carrying out dehydrogenation reaction on the full-hydrogenated organic liquid hydrogen storage material to produce hydrogen; the gas-liquid separator is connected with the dehydrogenation reactor and is used for separating hydrogen; the hydrogen production heat of the aluminum water reactor is supplied to the dehydrogenation reactor for dehydrogenation; the first mixer is respectively connected with the solid-gas separator and the gas-liquid separator and is used for mixing hydrogen prepared by the aluminum water hydrogen production part and hydrogen prepared by the dehydrogenation part; the first mixer is connected to a fuel cell stack. The heat utilization efficiency can be improved.

Description

Technical Field

[0001] The present application relates to the field of fuel cell technology, and in particular to a hydrogen production unit of a fuel cell stack, a cooling, heating and power cogeneration system and method. Background Art

[0002] In recent years, with the development of my country's economy, the problem of tight energy supply has become increasingly prominent. Traditional energy has problems such as non-renewable and serious environmental pollution. Hydrogen is a renewable clean energy. High-temperature proton exchange membrane fuel cells using hydrogen as fuel can efficiently convert energy and have the characteristics of high performance, low emissions, high power density and simple stacking design. In the design process of energy utilization, it is necessary to consider not only the renewability and environmental protection issues, but also the utilization efficiency of energy utilization.

[0003] In the utilization process of high-temperature proton exchange membrane fuel cells, a single hydrogen production unit is generally used. In the hydrogen production process, there is usually heat waste or huge energy demand, resulting in high unit energy consumption and low energy utilization efficiency.

[0004] High-temperature proton exchange membrane fuel cells can achieve integrated output of cooling, heat and electricity, which can effectively save energy and alleviate environmental problems. However, in the combined cooling, heating and power system, there are also problems such as large waste heat loss and low utilization efficiency. Summary of the invention

[0005] Based on this, it is necessary to provide a hydrogen production unit, a combined heat and power system and method for a fuel cell stack, and the specific technical solutions are as follows.

[0006] A hydrogen production unit for a fuel cell stack, comprising: The aluminum molten metal hydrogen production part includes an aluminum molten metal reactor and a solid-gas separator; the aluminum molten metal reactor is used for aluminum molten metal reaction to produce hydrogen; the solid-gas separator is connected to the aluminum molten metal reactor to separate hydrogen; The dehydrogenation part includes a dehydrogenation reactor and a gas-liquid separator; the dehydrogenation reactor is used to fully hydrogenate the organic liquid hydrogen storage material to carry out dehydrogenation reaction to produce hydrogen; the gas-liquid separator is connected to the dehydrogenation reactor to separate hydrogen; the heat produced by the aluminum water reactor is supplied to the dehydrogenation reactor for dehydrogenation; The first mixer is connected to the solid-gas separator and the gas-liquid separator respectively, and is used to mix the hydrogen prepared by the aluminum water hydrogen production part and the hydrogen prepared by the dehydrogenation part; the first mixer is connected to the fuel cell stack.

[0007] Furthermore, it also includes a fully hydrogenated organic liquid hydrogen storage material preheater and a hydrogen burner; The fully hydrogenated organic liquid hydrogen storage material preheater is connected to the dehydrogenation reactor and is used to preheat the fully hydrogenated organic liquid hydrogen storage material; The hydrogen burner is connected to the anode of the fuel cell stack to receive the anode tail gas and mix it with air for combustion; the hydrogen burner is connected to the fully hydrogenated organic liquid hydrogen storage material preheater to provide heat for preheating.

[0008] Furthermore, it also includes an air preheater, which is connected to the fuel cell stack and is used to input air into the fuel cell stack; the air preheater is provided with heat by the cathode tail gas of the fuel cell stack.

[0009] A combined cooling, heating and power system, comprising: A hydrogen production unit as described in any one of the above items; Fuel cell stack; The primary cooling unit includes a heat transfer part and a CO2-ion liquid circulation part; the heat transfer part is connected to the fuel cell stack and is used to guide the heat transfer oil of the fuel cell stack to heat the CO2-ion liquid in the CO2-ion liquid circulation part until it decomposes; the CO2-ion liquid circulation part is used to decompose the CO2-ion liquid, mix and circulate, and refrigerate; The secondary cooling unit comprises an ammonia circulation part and a first waste heat exchanger; the ammonia circulation part is used to condense and evaporate the ammonia and refrigerate; the first waste heat exchanger is connected to the gas-liquid separator, and is used to receive the liquid hydrogen storage material, and make the liquid hydrogen storage material absorb the heat released by the condensation of the ammonia; The secondary power supply unit comprises an ammonia-water working medium circulation part, a second waste heat exchanger and a turbine; the ammonia-water working medium circulation part is used to decompose and mix the ammonia-water working medium; the second waste heat exchanger is connected to the first waste heat exchanger and is used to receive liquid hydrogen storage material so that the liquid hydrogen storage material provides heat for the decomposition of the ammonia-water working medium; the turbine is located in the ammonia-water working medium circulation part and is driven by ammonia to generate electricity; The heating unit includes a third waste heat exchanger; the third waste heat exchanger is connected to the second waste heat exchanger and is used to receive liquid hydrogen storage material so that the liquid hydrogen storage material heats domestic water.

[0010] Further, the CO2-ion liquid circulation part includes a generator, a first condenser, a first evaporator and an absorber; The generator is used for heat exchange between CO2-ion liquid and heat transfer oil to form CO2 gas and ion liquid; The first condenser is connected to the generator and is used to receive and condense CO2 gas; The first evaporator is connected to the first condenser and is used to receive CO2 liquid and evaporate it to absorb heat and provide cooling; The absorber is connected to the generator and the first condenser respectively, and is used to receive CO2 gas and ionic liquid and mix them to form CO2-ionic liquid. The absorber is also used to circulate the CO2-ionic liquid into the generator.

[0011] Furthermore, a third regenerator is provided between the absorber and the generator, and the third regenerator is used to receive the high-temperature ionic liquid from the generator and the low-temperature CO2- ion liquid from the absorber, respectively, so that the high-temperature ionic liquid and the low-temperature CO2- ion liquid exchange heat; A first regenerator is also provided between the generator and the first condenser, and the first regenerator is used to receive high-temperature CO2 gas from the generator and low-temperature CO2-ion liquid from the absorber, so that the high-temperature CO2 gas and the low-temperature CO2-ion liquid can exchange heat.

[0012] Furthermore, a second regenerator and a first throttle valve are provided between the first condenser and the first evaporator; the second regenerator is used to receive the CO2 liquid from the first condenser and the CO2 gas from the first evaporator, respectively, so that the CO2 liquid is supercooled and flows to the first evaporator through the first throttle valve, and the CO2 gas is superheated and flows to the absorber.

[0013] Furthermore, the ammonia circulation part includes a second evaporator, which is connected to the first waste heat exchanger and is used to receive liquid ammonia condensed by the first waste heat exchanger and evaporate the liquid ammonia to form ammonia gas; the first waste heat exchanger is used to receive ammonia gas to condense the ammonia gas, and the heat released by the condensation of the ammonia gas is absorbed by the liquid hydrogen storage material.

[0014] Furthermore, the ammonia-water working medium circulation part includes a second mixer, a second condenser and a fourth regenerator; The fourth regenerator is connected to the second waste heat exchanger and is used to receive the ammonia-poor working fluid generated by the second waste heat exchanger; The second mixer is connected to the second waste heat exchanger and the fourth regenerator respectively, and is used to receive the ammonia-rich steam generated by the second waste heat exchanger and the ammonia-poor working medium flowing through the fourth regenerator, and mix them into an ammonia-water working medium; The second condenser is connected to the second mixer and the fourth heat exchanger respectively, and is used to receive the ammonia-water working medium from the second mixer, cool the ammonia-water working medium, and transport the low-temperature ammonia-water working medium to the fourth regenerator for heat exchange with the high-temperature ammonia-poor working medium.

[0015] A method for using the combined cooling, heating and power system as described in any one of the above items comprises the following steps: Aluminum and water raw materials are added to the aluminum-water hydrogen production part to produce hydrogen by aluminum-water reaction; fully hydrogenated organic liquid hydrogen storage materials are added to the dehydrogenation part to produce hydrogen by dehydrogenation reaction; hydrogen produced by aluminum-water reaction and hydrogen produced by dehydrogenation reaction are mixed and then transported to the fuel cell stack; the heat generated by aluminum-water reaction to produce hydrogen is used to heat the dehydrogenation reaction, and the temperature of the dehydrogenation reaction is controlled by the amount of aluminum added; The waste heat from the fuel cell stack is used to heat the CO2-ion liquid using heat-conducting oil to generate CO2 gas and ion liquid; the CO2 gas is cooled and then evaporated to absorb heat to provide cooling to the outside world; the CO2 gas is mixed with the ion liquid to form an initial CO2-ion liquid solution for circulation; The dehydrogenated organic hydrogen storage liquid is used to absorb heat from ammonia, so that the cooled ammonia evaporates and absorbs heat to provide cooling to the outside, and the evaporated ammonia absorbs heat to form a cycle; The waste heat after dehydrogenation of the organic hydrogen storage liquid and the heat absorbed by the ammonia are used to heat the ammonia-water working medium to generate ammonia-rich steam and ammonia-lean working medium; the ammonia-rich steam is used to generate power in a turbine, and the ammonia-rich steam after generating power is mixed with the ammonia-lean working medium again to form the initial ammonia-water working medium for circulation; The waste heat from heating the ammonia-water working medium with organic hydrogen storage liquid is used to heat the room temperature water to produce domestic hot water.

[0016] Beneficial effects: 1. The hydrogen production unit of a fuel cell stack provided by the present invention adopts a combination of aluminum water hydrogen production and dehydrogenation to provide hydrogen for the fuel cell stack. During the hydrogen production process, the heat released by the aluminum water reaction is provided to the fully hydrogenated organic liquid hydrogen storage material for dehydrogenation reaction, so that the two hydrogen production reactions are thermally coupled, thereby reducing heat loss during the hydrogen production process of the fuel cell stack, reducing additional heat demand, and improving heat utilization efficiency.

[0017] 2. The hydrogen production unit of a fuel cell stack provided by the present invention utilizes cathode exhaust gas to preheat the air, and utilizes the combustion of anode exhaust gas and air to preheat the fully hydrogenated organic liquid hydrogen storage material, thereby further reducing heat loss during the hydrogen production process of the fuel cell stack, reducing additional heat demand, and improving heat utilization efficiency.

[0018] 3. A combined heat and power system provided by the present invention utilizes heat transfer oil to provide heat from the fuel cell stack during power generation to the CO2- ion liquid for heating, thereby decomposing it into CO2- ion liquid; and a decomposition-mixing cycle is performed in the primary cooling unit to achieve refrigeration during the cycle, thereby improving the utilization rate of the reaction heat of the fuel cell stack; the low-grade waste heat carried by the organic hydrogen storage liquid in the fuel and the heat released by the ammonia refrigeration cycle are utilized to drive the Kalina cycle, that is, the ammonia-water working fluid cycle for power generation, and the power generation and waste heat utilization rate of the combined heat and power system are improved by reasonably coupling the waste heat.

[0019] 4. The present invention provides a combined cooling, heating and power system, which utilizes the heat released by the aluminum-water reaction to drive the dehydrogenation of the fully hydrogenated organic liquid hydrogen storage material; utilizes the reaction heat of the fuel cell stack to drive the primary cooling unit; utilizes the low-grade waste heat of the organic hydrogen storage liquid to sequentially drive the secondary cooling unit, the secondary power supply unit and the heating unit according to the cascade utilization of energy; and performs heat exchange adaptation on the temperatures of different cascades, thereby improving the multi-stage energy utilization of the system.

[0020] 5. The method of using the combined heat, cooling and power system provided by the present invention reduces heat loss, improves heat utilization efficiency, reduces additional heat demand, improves the multi-level energy utilization of the system, and meets the needs of production and life for simultaneous power supply, cooling and heating. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 is a schematic diagram of a hydrogen production unit; Figure 2 Schematic diagram of the combined cooling, heating and power system.

[0023] Explanation of the reference numerals: 1. water preheater; 2. aluminum water reactor; 3. solid-gas separator; 4. aluminum thermal product recovery device; 5. fully hydrogenated organic liquid hydrogen storage material preheater; 6. dehydrogenation reactor; 7. gas-liquid separator; 8. first mixer; 9. hydrogen compressor; 10. high-temperature proton exchange membrane fuel cell; 11. hydrogen burner; 12. air preheater; 13. air compressor; 14. first delivery pump; 15. generator; 16. first regenerator; 17. first condenser; 18. second regenerator; 19. first Throttle valve; 20, first evaporator; 21, absorber; 22, second delivery pump; 23, flow distribution valve; 24, third regenerator; 25, second throttle valve; 26, first waste heat exchanger; 27, third throttle valve; 28, second evaporator; 29, third delivery pump; 30, second waste heat exchanger; 31, turbine; 32, second mixer; 33, second condenser; 34, fourth delivery pump; 35, fourth regenerator; 36, fourth throttle valve; 37, third waste heat exchanger; 38, organic hydrogen storage liquid recovery device. DETAILED DESCRIPTION

[0024] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0025] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0027] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0029] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0030] Example 1 This embodiment provides a hydrogen production unit for a fuel cell stack, referring to Figure 1 As shown, it includes an aluminum water hydrogen production part, a dehydrogenation part and a first mixer 8.

[0031] Specifically, the aluminum molten metal hydrogen production part includes an aluminum molten metal reactor 2 and a solid-gas separator 3; the aluminum molten metal reactor 2 is used for aluminum molten metal reaction to produce hydrogen. Raw aluminum and raw water are input into the aluminum molten metal reactor 2 to react and produce hydrogen, and the reaction process is: Al+H2O→Al(OH)3+H2. Heat is released during the process of aluminum molten metal reaction to produce hydrogen.

[0032] Specifically, the dehydrogenation part includes a dehydrogenation reactor 6 and a gas-liquid separator 7; the dehydrogenation reactor 6 is used to fully hydrogenate the organic liquid hydrogen storage material to produce hydrogen through dehydrogenation reaction. The dehydrogenation process is H n -LOHCs→LOHCs+n / 2H2. The dehydrogenation process requires the absorption of heat, and the heat produced by the aluminum water reactor 2 is supplied to the dehydrogenation reactor 6 for dehydrogenation, thereby achieving thermal coupling in the hydrogen production process. The gas-liquid separator 7 is connected to the dehydrogenation reactor 6 for separating hydrogen.

[0033] Specifically, the first mixer 8 is connected to the solid-gas separator 3 and the gas-liquid separator 7 respectively, and is used to mix the hydrogen prepared by the aluminum water hydrogen production part and the hydrogen prepared by the dehydrogenation part; and the mixed hydrogen is supplied to the fuel cell stack. A hydrogen compressor 9 is arranged between the first mixer 8 and the fuel cell stack, and the hydrogen is refueled by the hydrogen compressor 9 and then transported to the fuel cell stack to provide fuel for the fuel cell stack.

[0034] Specifically, in the solid-gas separator 3, hydrogen is separated from the aluminothermic product solids, and the hydrogen is transported to the first mixer 8. The solid-gas separator 3 is also connected to the aluminothermic product recoverer 4, and the aluminothermic product recoverer 4 is used to recover the aluminothermic product solids to achieve resource recovery.

[0035] Specifically, hydrogen is separated from the organic liquid hydrogen storage material in the gas-liquid separator 7, and the hydrogen is transported to the first mixer 8. In this embodiment, the organic liquid hydrogen storage material can be recovered, and the organic liquid hydrogen storage material can also be used for waste heat in the next stage.

[0036] The hydrogen production unit of a fuel cell stack provided in this embodiment uses a combination of aluminum water hydrogen production and dehydrogenation to provide hydrogen for the fuel cell stack. During the hydrogen production process, the heat released by the aluminum water reaction is provided to the fully hydrogenated organic liquid hydrogen storage material for dehydrogenation reaction, so that the two hydrogen production reactions are thermally coupled, thereby reducing heat loss during the hydrogen production process of the fuel cell stack, reducing additional heat demand, and improving heat utilization efficiency.

[0037] Specifically, it also includes a fully hydrogenated organic liquid hydrogen storage material preheater 5 and a hydrogen burner 11; the fully hydrogenated organic liquid hydrogen storage material preheater 5 is connected to the dehydrogenation reactor 6, and is used to preheat the fully hydrogenated organic liquid hydrogen storage material. Before dehydrogenation, the fully hydrogenated organic liquid hydrogen storage material is first preheated by the fully hydrogenated organic liquid hydrogen storage material preheater 5 to improve the dehydrogenation effect. Specifically, the hydrogen burner 11 is connected to the anode of the fuel cell stack, and is used to receive the anode tail gas and mix it with air for combustion; the hydrogen burner 11 is connected to the fully hydrogenated organic liquid hydrogen storage material preheater 5 to provide heat for preheating. By mixing the anode tail gas with air for combustion and utilizing the anode tail gas, the energy utilization rate of the entire system is improved, and the additional heat demand is reduced.

[0038] Specifically, it also includes a water preheater 1, which is connected to the aluminum water reactor 2. Before the raw water is input into the aluminum water reactor 2, the water is preheated to improve the effect of the aluminum water reaction.

[0039] Specifically, it also includes an air preheater, and the air preheater 12 is connected to the fuel cell stack through an air compressor 13, and is used to input air into the fuel cell stack to provide oxygen for the fuel cell stack combustion. The air preheater 12 is provided with heat by the cathode tail gas of the fuel cell stack. By preheating the air, the combustion effect of the fuel cell is improved, and the cathode tail gas of the fuel cell stack provides heat for air preheating, which further improves the utilization efficiency of heat and reduces heat loss.

[0040] The hydrogen production unit of a fuel cell stack provided in this embodiment uses cathode exhaust gas to preheat the air, and uses the combustion of anode exhaust gas and air to preheat the fully hydrogenated organic liquid hydrogen storage material, thereby further reducing heat loss during the hydrogen production process of the fuel cell stack, reducing additional heat demand, and improving heat utilization efficiency.

[0041] Example 2 This embodiment provides a combined cooling, heating and power system. Figure 2 As shown, it includes a hydrogen production unit, a fuel cell stack, a primary cooling unit, a secondary cooling unit, a secondary power supply unit, and a heating unit as described in Example 1.

[0042] Specifically, the primary cooling unit includes a heat conduction part and a CO2-ion liquid circulation part; the heat conduction part is connected to the fuel cell stack, and is used to guide the heat conduction oil of the fuel cell stack to heat the CO2-ion liquid in the CO2-ion liquid circulation part until it decomposes. The heat conduction part can adopt a pipeline structure, so that its head and tail are respectively connected to the fuel cell stack, and a first delivery pump 14 is provided on the pipeline structure to make the heat conduction oil flow through the pipeline structure during the circulation process. The heat generated by the combustion of the fuel cell stack is used to heat the CO2-ion liquid, so that it decomposes to produce CO2 gas and ion liquid. The CO2-ion liquid circulation part is used to decompose the CO2-ion liquid and mix it in a cycle, and refrigeration is used to achieve a cooling effect during the circulation process.

[0043] Specifically, the CO2-ion liquid circulation part includes a generator 15, a first condenser 17, a first evaporator 20 and an absorber 21. The generator 15 is used for heat exchange between CO2-ion liquid and heat transfer oil to form CO2 gas and ion liquid; the first condenser 17 is connected to the generator 15, and is used to receive CO2 gas and condense; the first evaporator 20 is connected to the first condenser 17, and is used to receive CO2 liquid and evaporate to absorb heat and provide cooling; the absorber 21 is connected to the generator 15 and the first condenser 17, respectively, and is used to receive CO2 gas and ion liquid and mix to form CO2-ion liquid, and the absorber 21 is also used to circulate the CO2-ion liquid into the generator 15. It should be noted that in the absorber 21, CO2-ion liquid is formed by mixing CO2 gas with ion liquid, and heat will be released during the mixing process, thereby reducing the temperature of the CO2-ion liquid, and the CO2-ion liquid is decomposed by heating the heat transfer oil in the subsequent process.

[0044] Heat from the fuel cell stack power generation process is provided to the CO2-ion liquid for heating by heat transfer oil, which decomposes it into CO2-ion liquid. A decomposition-mixing cycle is then carried out in the primary cooling unit to achieve refrigeration during the cycle, thereby improving the utilization rate of the reaction heat of the fuel cell stack.

[0045] Specifically, a third regenerator 24 is provided between the absorber 21 and the generator 15, and the third regenerator 24 is used to receive the high-temperature ion liquid from the generator 15 and the low-temperature CO2-ion liquid from the absorber 21, so that the high-temperature ion liquid and the low-temperature CO2-ion liquid can exchange heat; a first regenerator 16 is provided between the generator 15 and the first condenser 17, and the first regenerator 16 is used to receive the high-temperature CO2 gas from the generator 15 and the low-temperature CO2-ion liquid from the absorber 21, so that the high-temperature CO2 gas and the low-temperature CO2-ion liquid can exchange heat. It should be noted that a second throttle valve 25 is provided between the third regenerator 24 and the absorber 21, so that the ion liquid flowing through the third regenerator 24 flows into the absorber 21 through the second throttle valve 25. A second delivery pump 22 valve is provided between the absorber 21 and the third regenerator 24, and the second delivery pump 22 is also provided with a branch flowing to the first regenerator 16, and a flow distribution valve 23 is provided on the branch, so that the low-temperature CO2-ion liquid flowing out of the absorber 21 enters the third regenerator 24 and the first regenerator 16 respectively, which respectively plays the effect of preheating the CO2-ion liquid, reducing the temperature of the CO2 gas, and reducing the temperature of the ion liquid, further improving the utilization efficiency of the heat inside the system and increasing the power generation.

[0046] Specifically, a second reheater 18 and a first throttle valve 19 are provided between the first condenser 17 and the first evaporator 20; the second reheater 18 is used to receive the CO2 liquid from the first condenser 17 and the CO2 gas from the first evaporator 20, respectively, so that the CO2 liquid is supercooled and flows to the first evaporator 20 through the first throttle valve 19, and the CO2 gas is superheated and flows to the absorber 21.

[0047] Specifically, the secondary cooling unit includes an ammonia circulation part and a first waste heat exchanger 26; the ammonia circulation part is used to condense and evaporate the ammonia and refrigerate; the first waste heat exchanger 26 is connected to the gas-liquid separator 7, and is used to receive liquid hydrogen storage material and allow the liquid hydrogen storage material to absorb the heat released by the condensation of ammonia.

[0048] Specifically, the ammonia circulation part includes a second evaporator 28, which is connected to the first waste heat exchanger 26 and is used to receive liquid ammonia condensed by the first waste heat exchanger 26 and evaporate the liquid ammonia to form ammonia gas; the first waste heat exchanger 26 is used to receive ammonia gas to condense the ammonia gas, and the heat released by the condensation of the ammonia gas is absorbed by the liquid hydrogen storage material.

[0049] A third throttle valve 27 and a third delivery pump 29 are respectively provided between the second evaporator 28 and the first waste heat exchanger 26, so that the ammonia gas is cooled in the first waste heat exchanger 26 and then flows through the third throttle valve 27 into the second evaporator 28, where it evaporates and absorbs heat, thereby cooling the outside; subsequently, the ammonia gas is compressed into a high-temperature gas by the third delivery pump 29 and then enters the first waste heat exchanger 26 to be condensed into a low-temperature state.

[0050] Specifically, the secondary power supply unit includes an ammonia-water working medium circulation part, a second waste heat exchanger 30 and a turbine 31; the ammonia-water working medium circulation part is used to decompose and mix the ammonia-water working medium; the second waste heat exchanger 30 is connected to the first waste heat exchanger 26, and is used to receive liquid hydrogen storage material so that the liquid hydrogen storage material provides heat for the decomposition of the ammonia-water working medium; the turbine 31 is located in the ammonia-water working medium circulation part, and is driven by ammonia to perform work and generate electricity.

[0051] Specifically, the ammonia-water working medium circulation part includes a second mixer 32, a second condenser 33 and a fourth reheater 35; the fourth reheater 35 is connected to the second waste heat exchanger 30, and is used to receive the ammonia-lean working medium generated by the second waste heat exchanger 30; the second mixer 32 is connected to the second waste heat exchanger 30 and the fourth reheater 35 respectively, and is used to receive the ammonia-rich steam generated by the second waste heat exchanger 30 and the ammonia-lean working medium flowing through the fourth reheater 35, and mix them into ammonia-water working medium; the second condenser 33 is connected to the second mixer 32 and the fourth heat exchanger respectively, and is used to receive the ammonia-water working medium from the second mixer 32, cool the ammonia-water working medium, and transport the low-temperature ammonia-water working medium to the fourth reheater 35 for heat exchange with the high-temperature lean ammonia working medium.

[0052] The low-grade waste heat of the organic hydrogen storage liquid in the fuel and the heat released by the ammonia refrigeration cycle are used to drive the Kalina cycle, that is, the ammonia-water working fluid cycle power generation. By reasonably coupling the waste heat, the power generation and waste heat utilization rate of the combined heat, cooling and power system are improved.

[0053] A fourth throttle valve 36 is provided between the second mixer 32 and the fourth heat exchanger, so that the ammonia-poor working medium passing through the fourth regenerator 35 enters the second mixer 32 through the fourth throttle valve 36. A fourth delivery pump 34 is provided between the second condenser 33 and the fourth regenerator 35, and the ammonia-water working medium in the second mixer 32 is input into the second waste heat exchanger 30 by the second delivery pump 22.

[0054] Specifically, the heating unit includes a third waste heat exchanger 37; the third waste heat exchanger 37 is connected to the second waste heat exchanger 30, and is used to receive liquid hydrogen storage materials so that the liquid hydrogen storage materials heat domestic water. The third waste heat exchanger 37 is also connected to an organic hydrogen storage liquid recovery device 38 to recover the organic hydrogen storage liquid to avoid waste of resources.

[0055] A combined cooling, heating and power system provided in this embodiment utilizes the heat released by the aluminum-water reaction to drive the dehydrogenation of the fully hydrogenated organic liquid hydrogen storage material; utilizes the reaction heat of the fuel cell stack to drive the primary cooling unit; utilizes the low-grade waste heat carried by the organic hydrogen storage liquid to sequentially drive the secondary cooling unit, the secondary power supply unit and the heating unit according to the cascade utilization of energy; and performs heat exchange adaptation on the temperatures of different cascades, thereby improving the multi-stage energy utilization of the system.

[0056] Example 3 This embodiment provides a method for using the combined cooling, heating and power system as described in Embodiment 2, characterized in that it includes the following steps: S1. Aluminum and water raw materials are added to the aluminum-water hydrogen production part to carry out aluminum-water reaction to produce hydrogen; fully hydrogenated organic liquid hydrogen storage materials are added to the dehydrogenation part to carry out dehydrogenation reaction to produce hydrogen; hydrogen produced by aluminum-water reaction and hydrogen produced by dehydrogenation reaction are mixed and transported to the fuel cell stack; heat generated by aluminum-water reaction to produce hydrogen is used to heat the dehydrogenation reaction, and the temperature of the dehydrogenation reaction is controlled by the amount of aluminum added.

[0057] Specifically, the conversion rate of aluminum in the aluminum water reactor 2 is 1, the conversion rate of the fully hydrogenated organic liquid hydrogen storage material in the dehydrogenation reactor 6 is 1, and the operating temperature of the high-temperature proton exchange membrane fuel cell 10 is 175°C~190°C.

[0058] The waste heat brought out from the fuel cell stack is used to heat the CO2-ion liquid using heat transfer oil to generate CO2 gas and ion liquid; the CO2 gas is cooled and then evaporated to absorb heat to provide cooling to the outside world; the CO2 gas is mixed with the ion liquid to form an initial CO2-ion liquid solution for circulation.

[0059] Specifically, the CO2-ion liquid in the generator 15 is heated by heat transfer oil to generate CO2 gas and ion liquid. The heated high-temperature and high-pressure CO2 gas exchanges heat with the low-temperature and high-pressure CO2-ion liquid flowing through the second delivery pump 22 and the flow distribution valve 23 in the first regenerator 16, and then enters the first condenser 17 to release heat to become high-pressure room temperature gas, further enters the second regenerator 18 for supercooling, and then enters the first throttle valve 19 for throttling. Then, in the first evaporator 20, the CO2 liquid evaporates and absorbs latent heat to become CO2 vapor to cool the outside world, providing cold capacity for the outside world. 0 is superheated through the second regenerator 18 and enters the absorber 21, where it is mixed with the dilute solution coming out of the generator 15 and flowing through the third regenerator 24 and the second throttle valve 25 to form a concentrated solution, and then pressurized by the second delivery pump 22. Subsequently, the flow is controlled by the flow distribution valve 23, one branch flows into the first regenerator 16 to exchange heat with the high-temperature and high-pressure CO2 gas coming out of the generator 15, and the other branch flows into the third regenerator 24 to exchange heat with the high-temperature and high-pressure dilute solution coming out of the generator 15. After absorbing heat, the two concentrated solutions both flow into the generator 15 to be heated again, and the cycle of absorbing heat and providing cooling to the outside is repeated.

[0060] The dehydrogenated organic hydrogen storage liquid is used to absorb heat from ammonia, so that the cooled ammonia evaporates and absorbs heat to provide cooling to the outside, and the evaporated ammonia absorbs heat to form a cycle.

[0061] Specifically, the heat released by condensation in the first waste heat exchanger 26 can heat the dehydrogenated organic hydrogen storage liquid from the gas-liquid separator 7. The heated dehydrogenated organic hydrogen storage liquid increases in temperature and serves as a heat source for the second waste heat exchanger 30 to heat the ammonia-water working medium. The third delivery pump 29 compresses the high-temperature gas into the first waste heat exchanger 26 and condenses it into a low-temperature state, then flows through the third throttle valve 27 and the second evaporator 28, and finally flows back to the third delivery pump 29 to complete the refrigeration cycle, repeating the heat release and heat absorption process again, and the cycle provides coldness to the outside.

[0062] The waste heat after dehydrogenation of the organic hydrogen storage liquid and the heat absorbed by the ammonia are used to heat the ammonia-water working medium to generate ammonia-rich steam and ammonia-lean working medium; the ammonia-rich steam is used to generate power in the turbine 31, and the ammonia-rich steam after generating power is mixed with the ammonia-lean working medium again to form the initial ammonia-water working medium for circulation.

[0063] Specifically, the second waste heat exchanger 30 is located on the liquid discharge pipeline of the gas-liquid separator 7, and heats the ammonia-water working medium in the second waste heat exchanger 30 to generate ammonia-rich steam and ammonia-lean working medium; the heated ammonia-rich steam is used to perform work and generate electricity in the turbine 31, and the ammonia-rich working medium after performing work and power generation is mixed with the ammonia-lean working medium flowing out of the second waste heat exchanger 30, which is preheated by the fourth reheater 35 and the fourth throttle valve 36, in the second mixer 32 to form the initial ammonia-water working medium, and then the ammonia-water working medium flows from the second mixer 32 to the second condenser 33 for cooling, and then is pressurized by the fourth delivery pump 34 to flow into the fourth reheater 35, exchange heat with the ammonia-lean working medium flowing out of the second waste heat exchanger 30, and then flows into the second waste heat exchanger 30, and repeats the heat absorption and power generation process again.

[0064] The waste heat from heating the ammonia-water working medium with organic hydrogen storage liquid is used to heat the room temperature water to produce domestic hot water.

[0065] The method of using a combined heat, cooling and power system provided in this embodiment reduces heat loss, improves heat utilization efficiency, reduces additional heat demand, improves the multi-level energy utilization of the system, and meets the needs of production and life for simultaneous power, cooling and heating.

[0066] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A hydrogen production unit for a fuel cell stack, characterized in that: include: The aluminum molten metal hydrogen production part includes an aluminum molten metal reactor and a solid-gas separator; the aluminum molten metal reactor is used for aluminum molten metal reaction to produce hydrogen; the solid-gas separator is connected to the aluminum molten metal reactor to separate hydrogen; The dehydrogenation part includes a dehydrogenation reactor and a gas-liquid separator; the dehydrogenation reactor is used to fully hydrogenate the organic liquid hydrogen storage material to carry out dehydrogenation reaction to produce hydrogen; the gas-liquid separator is connected to the dehydrogenation reactor to separate hydrogen; the heat produced by the aluminum water reactor is supplied to the dehydrogenation reactor for dehydrogenation; The first mixer is connected to the solid-gas separator and the gas-liquid separator respectively, and is used to mix the hydrogen prepared by the aluminum water hydrogen production part and the hydrogen prepared by the dehydrogenation part; the first mixer is connected to the fuel cell stack.

2. A hydrogen production unit for a fuel cell stack according to claim 1, characterized in that: It also includes a fully hydrogenated organic liquid hydrogen storage material preheater and a hydrogen burner; The fully hydrogenated organic liquid hydrogen storage material preheater is connected to the dehydrogenation reactor and is used to preheat the fully hydrogenated organic liquid hydrogen storage material; The hydrogen burner is connected to the anode of the fuel cell stack to receive the anode tail gas and mix it with air for combustion; the hydrogen burner is connected to the fully hydrogenated organic liquid hydrogen storage material preheater to provide heat for preheating.

3. A hydrogen production unit for a fuel cell stack according to claim 1, characterized in that: It also includes an air preheater, which is connected to the fuel cell stack and is used to input air into the fuel cell stack; the air preheater is provided with heat by the cathode tail gas of the fuel cell stack.

4. A combined cooling, heating and power system, characterized in that: include: The hydrogen production unit according to any one of claims 1 to 3; Fuel cell stack; The primary cooling unit includes a heat transfer part and a CO2-ion liquid circulation part; the heat transfer part is connected to the fuel cell stack and is used to guide the heat transfer oil of the fuel cell stack to heat the CO2-ion liquid in the CO2-ion liquid circulation part until it decomposes; the CO2-ion liquid circulation part is used to decompose the CO2-ion liquid, mix and circulate, and refrigerate; The secondary cooling unit comprises an ammonia circulation part and a first waste heat exchanger; the ammonia circulation part is used to condense and evaporate the ammonia and refrigerate; the first waste heat exchanger is connected to the gas-liquid separator, and is used to receive the liquid hydrogen storage material, and make the liquid hydrogen storage material absorb the heat released by the condensation of the ammonia; The secondary power supply unit comprises an ammonia-water working medium circulation part, a second waste heat exchanger and a turbine; the ammonia-water working medium circulation part is used to decompose and mix the ammonia-water working medium; the second waste heat exchanger is connected to the first waste heat exchanger and is used to receive liquid hydrogen storage material so that the liquid hydrogen storage material provides heat for the decomposition of the ammonia-water working medium; the turbine is located in the ammonia-water working medium circulation part and is driven by ammonia to generate electricity; The heating unit includes a third waste heat exchanger; the third waste heat exchanger is connected to the second waste heat exchanger and is used to receive liquid hydrogen storage material so that the liquid hydrogen storage material heats domestic water.

5. A combined cooling, heating and power system according to claim 4, characterized in that: The CO2-ion liquid circulation part includes a generator, a first condenser, a first evaporator and an absorber; The generator is used for heat exchange between CO2-ion liquid and heat transfer oil to form CO2 gas and ion liquid; The first condenser is connected to the generator and is used to receive and condense CO2 gas; The first evaporator is connected to the first condenser and is used to receive CO2 liquid and evaporate it to absorb heat and provide cooling; The absorber is connected to the generator and the first condenser respectively, and is used to receive CO2 gas and ionic liquid and mix them to form CO2-ionic liquid. The absorber is also used to circulate the CO2-ionic liquid into the generator.

6. A combined cooling, heating and power system according to claim 5, characterized in that: A third regenerator is also provided between the absorber and the generator, and the third regenerator is used to receive the high-temperature ion liquid from the generator and the low-temperature CO2- ion liquid from the absorber, respectively, so that the high-temperature ion liquid and the low-temperature CO2- ion liquid can exchange heat; A first regenerator is also provided between the generator and the first condenser, and the first regenerator is used to receive high-temperature CO2 gas from the generator and low-temperature CO2-ion liquid from the absorber, so that the high-temperature CO2 gas and the low-temperature CO2-ion liquid can exchange heat.

7. The combined cooling, heating and power system according to claim 5, characterized in that: A second regenerator and a first throttle valve are also provided between the first condenser and the first evaporator; the second regenerator is used to receive the CO2 liquid from the first condenser and the CO2 gas from the first evaporator, respectively, so that the CO2 liquid flows to the first evaporator through the first throttle valve after being supercooled, and the CO2 gas flows to the absorber after being superheated.

8. The combined cooling, heating and power system according to claim 4, characterized in that: The ammonia circulation part includes a second evaporator, which is connected to the first waste heat exchanger and is used to receive liquid ammonia condensed by the first waste heat exchanger and evaporate the liquid ammonia to form ammonia gas; the first waste heat exchanger is used to receive ammonia gas to condense the ammonia gas, and the heat released by the condensation of the ammonia gas is absorbed by the liquid hydrogen storage material.

9. The combined cooling, heating and power system according to claim 4, characterized in that: The ammonia-water working medium circulation part includes a second mixer, a second condenser and a fourth regenerator; The fourth regenerator is connected to the second waste heat exchanger and is used to receive the ammonia-poor working fluid generated by the second waste heat exchanger; The second mixer is connected to the second waste heat exchanger and the fourth regenerator respectively, and is used to receive the ammonia-rich steam generated by the second waste heat exchanger and the ammonia-poor working medium flowing through the fourth regenerator, and mix them into an ammonia-water working medium; The second condenser is connected to the second mixer and the fourth heat exchanger respectively, and is used to receive the ammonia-water working medium from the second mixer, cool the ammonia-water working medium, and transport the low-temperature ammonia-water working medium to the fourth regenerator for heat exchange with the high-temperature ammonia-poor working medium.

10. A method for using the combined cooling, heating and power system according to any one of claims 4 to 9, characterized in that: The steps include: Aluminum and water raw materials are added to the aluminum-water hydrogen production part to produce hydrogen by aluminum-water reaction; fully hydrogenated organic liquid hydrogen storage materials are added to the dehydrogenation part to produce hydrogen by dehydrogenation reaction; hydrogen produced by aluminum-water reaction and hydrogen produced by dehydrogenation reaction are mixed and then transported to the fuel cell stack; the heat generated by aluminum-water reaction to produce hydrogen is used to heat the dehydrogenation reaction, and the temperature of the dehydrogenation reaction is controlled by the amount of aluminum added; The waste heat from the fuel cell stack is used to heat the CO2-ion liquid using heat-conducting oil to generate CO2 gas and ion liquid; the CO2 gas is cooled and then evaporated to absorb heat to provide cooling to the outside world; the CO2 gas is mixed with the ion liquid to form an initial CO2-ion liquid solution for circulation; The dehydrogenated organic hydrogen storage liquid is used to absorb heat from ammonia, so that the cooled ammonia evaporates and absorbs heat to provide cooling to the outside, and the evaporated ammonia absorbs heat to form a cycle; The waste heat after dehydrogenation of the organic hydrogen storage liquid and the heat absorbed by the ammonia are used to heat the ammonia-water working medium to generate ammonia-rich steam and ammonia-lean working medium; the ammonia-rich steam is used to generate power in a turbine, and the ammonia-rich steam after generating power is mixed with the ammonia-lean working medium again to form the initial ammonia-water working medium for circulation; The waste heat from heating the ammonia-water working medium with organic hydrogen storage liquid is used to heat the room temperature water to produce domestic hot water.

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