Power generation system based on adhp and pemfc

Abstract

The application relates to the technical field of power generation, and discloses a power generation system based on ADHP and PEMFC. The system comprises a waste heat recovery subsystem, an ammonia decomposition hydrogen production subsystem and a fuel cell subsystem; the waste heat recovery subsystem is used for recovering the heat of a turbocharged engine tail gas of an external heat source and the heat of a combustor reaction; the ammonia decomposition hydrogen production subsystem obtains heat from the external heat source to preheat liquid ammonia accessed, and uses the preheated ammonia gas to carry out an ammonia decomposition reaction; the fuel cell subsystem accesses the hydrogen produced by the ammonia decomposition hydrogen production subsystem, uses the accessed hydrogen gas and air as reaction raw materials to carry out an electrochemical reaction based on a proton exchange membrane fuel cell to generate electric energy, uses the heat generated by the combustor reaction to preheat the accessed air, provides heat for the ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem, and transports the air to the waste heat recovery subsystem to recover heat. The embodiment of the application can improve the thermal efficiency of a power system.

Description

Technical Field

[0001] The present application relates to the field of power generation technology, and in particular to a power generation system based on ADHP and PEMFC. Background Art

[0002] Hydrogen energy is a clean secondary energy source with excellent properties such as high calorific value, good combustion performance, environmental friendliness, and recyclability. The only product produced by its reaction with oxygen is water. However, hydrogen is flammable and explosive, and its low volume density makes it difficult to store and transport. Therefore, the terminal use cost of hydrogen energy has remained high. Ammonia, on the other hand, is stable in nature, and its preparation process is mature, making it easy to obtain, transport, and store. Using ammonia as a carrier, obtaining hydrogen through ammonia decomposition and coupling it with hydrogen fuel cells has become an effective way to utilize hydrogen energy. However, existing ammonia decomposition fuel cell systems have the disadvantage of low energy utilization. The heat generated during the combustion process cannot be well utilized, resulting in energy waste. Summary of the Invention

[0003] The purpose of this application is to provide a power generation system based on ADHP and PEMFC, aiming to combine ammonia decomposition to produce hydrogen and proton exchange membrane fuel cells to improve the thermal efficiency of the power system.

[0004] The present application provides a power generation system based on ADHP and PEMFC, including:

[0005] A waste heat recovery subsystem is connected to an external heat source to recover heat from the external heat source;

[0006] an ammonia decomposition hydrogen production subsystem connected to the waste heat recovery subsystem, obtaining heat from the waste heat recovery subsystem to preheat the incoming ammonia, and utilizing the preheated ammonia to perform an ammonia decomposition reaction;

[0007] The fuel cell subsystem is connected to the ammonia decomposition hydrogen production subsystem, receives the hydrogen produced from the ammonia decomposition hydrogen production subsystem, uses the received hydrogen and air as reaction raw materials to carry out an electrochemical reaction based on a proton exchange membrane fuel cell to generate electricity, and uses the heat generated by the burner reaction to preheat the received air, provide heat for the ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem, and transport the heat to the waste heat recovery subsystem for heat recovery.

[0008] In some embodiments, the waste heat recovery subsystem includes:

[0009] a pressurizing unit connected to the external heat source, pressurizing the external heat source, and preheating the ammonia gas connected to the ammonia decomposition hydrogen production subsystem through the pressurized heat source;

[0010] The waste heat recovery unit is connected to the booster unit to recover the heat in the heat source after heat exchange.

[0011] In some embodiments, the boosting unit includes a first turbocharger and a second turbocharger. The first turbocharger is connected to the ammonia decomposition hydrogen production subsystem and the waste heat recovery unit, and can drive the second turbocharger to rotate after rotation; the first turbocharger is connected to the exhaust gas of an external engine, and the connected exhaust gas is pressurized and then transported to the ammonia decomposition hydrogen production subsystem and the waste heat recovery unit in sequence; the second turbocharger is connected to the external air, and the connected air is pressurized and then transported to the ammonia decomposition hydrogen production subsystem.

[0012] In some embodiments, the waste heat recovery unit is an organic Rankine cycle topology, a supercritical carbon dioxide cycle power generation topology, or an absorption refrigeration topology.

[0013] In some embodiments, the ammonia decomposition hydrogen production subsystem includes:

[0014] The ammonia decomposition unit is connected to the external ammonia gas, performs high-temperature decomposition on the connected ammonia gas, and preheats the connected ammonia gas by the high-temperature gas connected to the waste heat recovery subsystem and the mixed gas obtained by the decomposition;

[0015] A separation unit is connected to the ammonia decomposition unit and the fuel cell subsystem, receives the mixed gas decomposed in the decomposition unit, performs pressure swing adsorption separation on the mixed gas, transmits the hydrogen obtained by pressure swing adsorption separation to the proton exchange membrane fuel cell subsystem, and cools and compresses the ammonia obtained by pressure swing adsorption separation and transmits it to the separation unit.

[0016] In some embodiments, the kinetic model of the ammonia decomposition hydrogen production subsystem is:

[0017] ,

[0018] ,

[0019] in, is the reaction rate of ammonia decomposition reaction, is the reaction constant of the ammonia decomposition reaction, is the pre-exponential factor, E is the activation energy, is the partial pressure of ammonia, is the partial pressure of hydrogen.

[0020] In some embodiments, the ammonia decomposition unit includes a first heat exchanger, a second heat exchanger and an ammonia decomposition reactor connected in sequence, and the separation unit includes a pressure swing adsorption separator, a first cooler, a first compressor and a second cooler connected in sequence; the first heat exchanger is connected to external ammonia, exchanges heat between the connected ammonia and the heat source of the waste heat recovery subsystem and then transports it to the second heat exchanger, the second heat exchanger exchanges heat between the connected ammonia and the mixed gas obtained by decomposition in the ammonia decomposition reactor and then transports it to the ammonia decomposition reactor, and the ammonia decomposition reactor transports the mixed gas obtained by decomposition to the second heat exchanger and the pressure swing adsorption separator in sequence; the pressure swing adsorption separator is connected to the fuel cell subsystem, performs pressure swing adsorption separation on the mixed gas obtained by decomposition, transports the hydrogen obtained by pressure swing adsorption separation to the fuel cell subsystem, and transports the ammonia obtained by pressure swing adsorption separation to the first cooler, the first compressor and the second cooler in sequence for cooling and compression, so that the cooled and compressed ammonia and the external ammonia are transported to the first heat exchanger.

[0021] In some embodiments, the fuel cell subsystem comprises:

[0022] A proton exchange membrane fuel cell having an anode side and a cathode side;

[0023] a heat exchange unit, connected to the ammonia decomposition hydrogen production subsystem and the cathode side, connected to external air, and heat-exchanging the connected air with the hydrogen produced by the ammonia decomposition hydrogen production subsystem before transporting the heat to the cathode side;

[0024] a washing unit connected to the heat exchange unit and the anode side, receiving the hydrogen after heat exchange and the hydrogen separated from the mixed gas output from the anode side, making the received hydrogen in a water vapor saturated state and delivering it to the anode side;

[0025] A combustion unit is connected to the washing unit and the cathode side, receives the mixed gas output from the cathode side, the impurities separated from the mixed gas output from the anode side, and the external air and performs a combustion reaction, and uses the heat generated by the combustion reaction to preheat the air in the heat exchange unit and provide heat for the ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem.

[0026] In some embodiments, the cell potential of the proton exchange membrane fuel cell is calculated as follows:

[0027] ,

[0028] in, is the battery potential, is the open circuit potential of the battery, For battery overvoltage, is the local current density, is the film thickness, is the membrane conductivity.

[0029] In some embodiments, the heat exchange unit includes a third heat exchanger and a fourth heat exchanger, the washing unit includes a second compressor, a washing device and a separation device, and the combustion unit includes a burner; the third heat exchanger is connected to external air and transported to the fourth heat exchanger and the inlet of the cathode side in sequence, the ammonia decomposition and hydrogen production subsystem transports the produced hydrogen to the third heat exchanger, the second compressor and the washing device in sequence, the washing device makes the connected hydrogen in a water vapor saturated state and transports it to the anode side, the separation device performs gas separation on the mixed gas output from the outlet of the anode side, and transports the separated hydrogen to the washing device, the burner is connected to the mixed gas output from the outlet of the cathode side, the impurities separated by the separation device and the external air and performs a combustion reaction, the heat generated by the combustion reaction is used to heat the ammonia decomposition and hydrogen production subsystem, and the water vapor generated by the combustion reaction is transported to the fourth heat exchanger to preheat the air connected to the inlet of the cathode side.

[0030] The beneficial effects of the present application are as follows: a heat recovery subsystem that can recover an external heat source, an ammonia decomposition hydrogen production subsystem that can perform ammonia decomposition to produce hydrogen, and a fuel cell subsystem based on a proton exchange membrane fuel cell are integrated. The heat generated by the external heat source and the electrochemical reaction of the fuel cell subsystem can be used to assist the ammonia decomposition hydrogen production subsystem in performing the ammonia decomposition hydrogen production reaction, and the heat generated by the ammonia decomposition hydrogen production reaction of the ammonia decomposition hydrogen production subsystem can be used to assist the fuel cell subsystem in performing the electrochemical reaction. The excess heat from both the ammonia decomposition hydrogen production reaction and the electrochemical reaction is recovered by the heat recovery subsystem and reused, thereby improving the thermal efficiency of the power generation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural diagram of a power generation system based on ADHP and PEMFC provided in an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0033] It should be noted that although the device schematics illustrate functional module divisions and the flowcharts illustrate logical sequences, in certain circumstances, the steps illustrated may be performed in a sequence that differs from the module divisions in the device or the sequence in the flowcharts. Terms such as "first" and "second" in the specification, claims, and drawings are used to distinguish similar items and are not intended to describe a specific sequence or precedence.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to be limiting of this application.

[0035] Referring to Figure 1 In an embodiment, the ADHP and PEMFC based power generation system comprises a waste heat recovery subsystem 1, an ammonia decomposition hydrogen production subsystem 2 and a fuel cell subsystem 3.

[0036] The waste heat recovery subsystem 1 is connected to an external heat source to recover heat from the external heat source. In the waste heat recovery subsystem 1, heat is absorbed from the fuel cell subsystem 3 through multiple heat exchanges with the ammonia decomposition hydrogen production subsystem 2 and the fuel cell subsystem 3 to utilize the absorbed heat for other purposes, such as driving a steam turbine generator to generate power, reducing energy loss and improving system energy utilization efficiency.

[0037] The ammonia decomposition hydrogen production subsystem 2 is connected to the waste heat recovery subsystem 1 to obtain heat from the waste heat recovery subsystem 1 to preheat ammonia gas inputted to perform ammonia decomposition reaction. In the hydrogen supplement subsystem, heat is obtained from the waste heat recovery subsystem 1 to preheat ammonia gas inputted to perform ammonia decomposition reaction. Hydrogen is provided by integrating ammonia decomposition hydrogen production technology. Ammonia decomposition catalysts (such as Ni / Al2O3 and Ru / Al2O3) can promote ammonia decomposition at a lower temperature range (300°C-650°C). When the temperature is 620°C, both catalysts can make the conversion rate of ammonia close to 100%. Hydrogen is separated from the mixed gas obtained by decomposition, and the remaining ammonia gas after separation is cooled and compressed for recycling to perform ammonia decomposition reaction.

[0038] The fuel cell subsystem 3 is connected to the ammonia decomposition hydrogen production subsystem 2 to input hydrogen produced by the ammonia decomposition hydrogen production subsystem 2 to perform electrochemical reaction based on proton exchange membrane fuel cell 31 using hydrogen and air as reaction raw materials to generate electric energy. Heat generated by the electrochemical reaction is used to preheat air inputted, provide heat for ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem 2 and be transported to the waste heat recovery subsystem 1 for heat recovery. In the fuel cell subsystem 3, hydrogen and air inputted from the ammonia decomposition hydrogen production subsystem 2 are used as reaction raw materials to perform electrochemical reaction based on proton exchange membrane fuel cell 31. Electric energy generated by the electrochemical reaction can be supplied to the outside. Heat generated by the combustor reaction is used to preheat air inputted, provide heat for ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem 2 and be transported to the waste heat recovery subsystem 1 for heat recovery to improve the thermal efficiency of the power system.

[0039] Referring again to Figure 1 In one embodiment, the waste heat recovery subsystem 1 includes a pressurizing unit 11 and a waste heat recovery unit 12. The pressurizing unit 11 is connected to an external heat source to pressurize the external heat source, and the pressurized heat source is used to preheat the ammonia gas connected to the ammonia decomposition hydrogen production subsystem 2. The waste heat recovery unit 12 is connected to the pressurizing unit 11 to recover heat from the heat source after heat exchange.

[0040] The boosting unit 11 boosts the input external heat source and then transmits it to the ammonia decomposition hydrogen production subsystem 2, so as to preheat the ammonia gas input to the ammonia decomposition hydrogen production subsystem 2 through the boosted heat source. After preheating the ammonia gas input to the ammonia decomposition hydrogen production subsystem 2, the heat source is transmitted to the waste heat recovery unit 12, and the waste heat recovery unit 12 recovers the heat in the heat source to provide heat to other facilities.

[0041] More specifically, the boosting unit 11 includes a first turbocharger TURBO1 and a second turbocharger TURBO2. The first turbocharger TURBO1 is connected to the ammonia decomposition hydrogen production subsystem 2 and the waste heat recovery unit 12. When it rotates, it drives the second turbocharger TURBO2 to rotate. The first turbocharger TURBO1 receives exhaust gas from an external engine, supercharges the exhaust gas, and then sequentially transmits it to the ammonia decomposition hydrogen production subsystem 2 and the waste heat recovery unit 12. The second turbocharger TURBO2 receives external air, supercharges the air, and then transmits it to the ammonia decomposition hydrogen production subsystem 2.

[0042] In actual use, the first turbocharger TURBO1 is connected to an external ammonia-diesel dual-fuel engine and ammonia decomposition hydrogen production subsystem 2. The waste heat recovery unit 12 is connected to the ammonia decomposition hydrogen production subsystem 2. The exhaust gas from the external ammonia-diesel dual-fuel engine is turbocharged. The first turbocharger TURBO1 transmits the turbocharged exhaust gas to the ammonia decomposition hydrogen production subsystem 2, where the turbocharged exhaust gas preheats the ammonia gas received by the ammonia decomposition hydrogen production subsystem 2. After passing through the ammonia decomposition hydrogen production subsystem 2, the turbocharged exhaust gas flows to the waste heat recovery unit 12, where the waste heat recovery unit 12 recovers heat from the heat source. The second turbocharger TURBO2 is connected to the ammonia decomposition hydrogen production subsystem 2 to turbocharge the air received from the external engine and then transmit it to the ammonia decomposition hydrogen production subsystem 2, allowing the ammonia decomposition hydrogen production subsystem 2 to operate under a pressurized environment. The first turbocharger TURBO1 operates after receiving the exhaust gas from the ammonia-diesel dual-fuel engine. The operating first turbocharger TURBO1 drives the second turbocharger TURBO2 to operate.

[0043] The waste heat recovery unit 12 may be an organic Rankine cycle topology, a supercritical carbon dioxide cycle power generation topology, or an absorption refrigeration topology. In this embodiment, the waste heat recovery unit 12 is an organic Rankine cycle topology.

[0044] See again Figure 1 In one embodiment, the ammonia decomposition hydrogen production subsystem 2 includes an ammonia decomposition unit 21 and a separation unit 22. The ammonia decomposition unit 21 is connected to external ammonia gas and is used to perform high-temperature decomposition of the connected ammonia gas, connect the high-temperature gas from the waste heat recovery subsystem 1, and preheat the decomposed mixed gas. The separation unit 22 connects the ammonia decomposition unit 21 and the fuel cell subsystem 3. The separation unit 22 is used to receive the mixed gas decomposed in the decomposition unit, perform pressure swing adsorption separation on the decomposed mixed gas, and transmit the hydrogen obtained by pressure swing adsorption separation to the proton exchange membrane fuel cell subsystem 31. The ammonia obtained by pressure swing adsorption separation is cooled, compressed, and transmitted to the separation unit 22.

[0045] The ammonia decomposition unit 21 is connected to the pre-stored ammonia from the outside. The connected ammonia is preheated by the high-temperature gas connected to the waste heat recovery subsystem 1, and then the preheated ammonia is used to perform a high-temperature decomposition reaction of ammonia. The chemical reaction formula of the high-temperature decomposition of ammonia is:

[0046] 2NH3⇌N2+3H2,

[0047] The ammonia decomposition unit 21 uses the mixed gas obtained by the high-temperature decomposition of ammonia to preheat the incoming ammonia again, and then transports the mixed gas obtained by the high-temperature decomposition of ammonia to the separation unit 22. The separation unit 22 separates hydrogen from the mixed gas obtained by the high-temperature decomposition of ammonia and transports it to the fuel cell subsystem 3. Ammonia is separated from the mixed gas obtained by the high-temperature decomposition of ammonia and is transported to the ammonia decomposition unit 21 again after cooling and compression. The remaining gas (mainly nitrogen) is directly discharged.

[0048] In a specific embodiment, the kinetic model of the ammonia decomposition hydrogen production subsystem 2 is:

[0049] ,

[0050] ,

[0051] in, is the reaction rate of ammonia decomposition reaction, is the reaction constant of the ammonia decomposition reaction, is the pre-exponential factor, E is the activation energy, is the partial pressure of ammonia, is the partial pressure of hydrogen.

[0052] More specifically, the ammonia decomposition unit 21 includes a first heat exchanger HEX1, a second heat exchanger HEX2 and an ammonia decomposition reactor RNH connected in sequence, and the separation unit 22 includes a pressure swing adsorption separator SEP1, a first cooler COOL1, a first compressor COMP1 and a second cooler COOL2 connected in sequence. The first heat exchanger HEX1 is connected to external ammonia, exchanges heat between the connected ammonia and the heat source of the waste heat recovery subsystem 1, and then transports it to the second heat exchanger HEX2. The second heat exchanger HEX2 exchanges heat between the connected ammonia and the mixed gas obtained by decomposition in the ammonia decomposition reactor RNH, and then transports it to the ammonia decomposition reactor RNH. The ammonia decomposition reactor RNH transports the decomposed mixed gas to the second heat exchanger HEX2 and the pressure swing adsorption separator SEP1 in sequence. The pressure swing adsorption separator SEP1 is connected to the fuel cell subsystem 3, performs pressure swing adsorption separation on the decomposed mixed gas, and transports the hydrogen obtained by the pressure swing adsorption separation to the fuel cell subsystem 3. The ammonia obtained by the pressure swing adsorption separation is sequentially transported to the first cooler COOL1, the first compressor COMP1, and the second cooler COOL2 for cooling and compression, so that the cooled and compressed ammonia and the external ammonia are transported to the first heat exchanger HEX1.

[0053] In actual application, the first heat exchanger HEX1 is connected to the waste heat recovery subsystem 1 and the external ammonia, so that the connected ammonia and the high-temperature gas in the waste heat recovery subsystem 1 are heat-exchanged to preheat the connected ammonia. The ammonia output from the first heat exchanger HEX1 enters the second heat exchanger HEX2. The second heat exchanger HEX2 is connected to the ammonia decomposition reactor RNH and is connected to the mixed gas output from the ammonia decomposition reactor RNH. The connected mixed gas and the connected ammonia are heat-exchanged to perform secondary preheating on the connected ammonia. The ammonia output from the second heat exchanger HEX2 enters the ammonia decomposition reactor RNH and undergoes a high-temperature ammonia decomposition reaction. The mixed gas after heat exchange in the second heat exchanger HEX2 is transported to the pressure swing adsorption separator SEP1. The pressure swing adsorption separator SEP1 performs pressure swing adsorption separation on the incoming mixed gas, separates out high-concentration hydrogen and delivers it to the fuel cell subsystem 3, separates out high-concentration ammonia and delivers it to the first cooler COOL1, and then passes through the first cooler COOL1, the first compressor COMP1 and the second cooler COOL2 for cooling and compression treatment, and then is connected to the first heat exchanger HEX1 with the external ammonia. The remaining gas is discharged to the outside of the power generation system.

[0054] See again Figure 1In one embodiment, the fuel cell subsystem 3 includes a proton exchange membrane fuel cell 31, a heat exchange unit 32, a washing unit 33, and a combustion unit 34. The proton exchange membrane fuel cell 31 has an anode side and a cathode side, and is used to perform an electrochemical reaction to generate electrical energy. The heat exchange unit 32 is connected to the ammonia decomposition hydrogen production subsystem 2 and the cathode side. The heat exchange unit 32 is connected to the external air, and the air is exchanged with the hydrogen produced by the ammonia decomposition hydrogen production subsystem 2 and then transported to the cathode side. The washing unit 33 is connected to the heat exchange unit 32 and the anode side. The washing unit 33 is connected to the hydrogen after heat exchange and the hydrogen separated from the mixed gas output from the anode side, so that the hydrogen is saturated with water vapor and transported to the anode side. The combustion unit 34 is connected to the washing unit 33 and the cathode side. The combustion unit 34 receives the mixed gas output from the cathode side, the impurities separated from the mixed gas output from the anode side, and the external air and performs a combustion reaction. The heat generated by the combustion reaction is used to preheat the air in the heat exchange unit 32 and provide heat for the ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem 2.

[0055] The electrochemical reaction of the proton exchange membrane fuel cell 31 is as follows:

[0056] Anode side: ,

[0057] Cathode side: ,

[0058] The proton exchange membrane fuel cell stack 31 was created using Aspen Custom Modeler (ACM). This model can be used to calculate the fuel cell voltage at a specified average current density. The heat exchange unit 32 connects the ammonia decomposition hydrogen production subsystem 2, the scrubbing unit 33, and the cathode side. It receives external air and hydrogen produced by the ammonia decomposition hydrogen production subsystem 2, exchanges heat between the air and hydrogen to preheat the air, then delivers the air to the scrubbing unit 33 and to the cathode side. The scrubbing unit 33 connects the anode inlet and outlet, scrubbing the hydrogen output from the heat exchange unit 32, saturating it with water vapor before delivering it to the anode inlet. The unreacted hydrogen is separated from the anode outlet and recovered. The recovered hydrogen is then combined with the hydrogen output from the heat exchange unit 32 and scrubbed. The combustion unit 34 is connected to the heat exchange unit 32 and the outlet on the cathode side, and is connected to the outlet on the cathode side to output the gas that has not undergone electrochemical reaction and the external air and to carry out a combustion reaction. The combustion unit 34 transports a part of the heat source generated by the combustion reaction to the heat exchange unit 32, so that the heat source generated by the combustion reaction and the hydrogen produced by the ammonia decomposition and hydrogen production subsystem 2 are heat-exchanged to preheat the hydrogen produced by the ammonia decomposition and hydrogen production subsystem 2 again. After the heat exchange, the heat source leaves the heat exchange unit 32 and is transported to the heat recovery subsystem. The combustion unit 34 transports another part of the heat source generated by the combustion reaction to the ammonia decomposition and hydrogen production subsystem 2 to provide heat for the ammonia decomposition and hydrogen production subsystem 2 to carry out the ammonia decomposition reaction.

[0059] In a specific embodiment, the calculation formula for the cell potential of the proton exchange membrane fuel cell 31 is:

[0060] ,

[0061] in, is the battery potential, is the open circuit potential of the battery, For battery overvoltage, is the local current density, is the film thickness, is the membrane conductivity.

[0062] More specifically, the heat exchange unit 32 includes a third heat exchanger HEX3 and a fourth heat exchanger HEX4. The scrubbing unit 33 includes a second compressor COMP2, a scrubbing unit HUM, and a separator SEP2. The combustion unit 34 includes a burner. The third heat exchanger HEX3 receives external air and sequentially delivers it to the fourth heat exchanger HEX4 and the cathode inlet. The ammonia decomposition hydrogen production subsystem 2 sequentially delivers the produced hydrogen to the third heat exchanger HEX3, the second compressor COMP2, and the scrubbing unit HUM. The scrubbing unit HUM saturates the received hydrogen with water vapor and delivers it to the anode. The separator SEP2 separates the mixed gas output from the anode outlet and delivers the separated hydrogen to the scrubbing unit HUM. The burner receives the mixed gas output from the cathode outlet, the impurities separated by the separator SEP2, and external air to undergo a combustion reaction. The heat generated by the combustion reaction is used to heat the ammonia decomposition hydrogen production subsystem 2. The water vapor generated by the combustion reaction is delivered to the fourth heat exchanger HEX4 to preheat the air connected to the cathode inlet.

[0063] In summary, the power generation system based on ADHP and PEMFC provided in the embodiment of the present application integrates a heat recovery subsystem that can recover an external heat source, an ammonia decomposition hydrogen production subsystem that can perform ammonia decomposition to produce hydrogen, and a fuel cell subsystem based on a proton exchange membrane fuel cell. The heat generated by the external heat source and the electrochemical reaction of the fuel cell subsystem can be used to assist the ammonia decomposition hydrogen production subsystem in performing the ammonia decomposition hydrogen production reaction, and the heat generated by the ammonia decomposition hydrogen production reaction of the ammonia decomposition hydrogen production subsystem can be used to assist the fuel cell subsystem in performing the electrochemical reaction. The excess heat of both the ammonia decomposition hydrogen production reaction and the electrochemical reaction is recovered by the heat recovery subsystem and reused, thereby improving the thermal efficiency of the power generation system.

[0064] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0065] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and essence of the present invention should be within the scope of the present invention.

Claims

1. A power generation system based on ADHP and PEMFC, characterized in that: include: A waste heat recovery subsystem is connected to the exhaust gas of the turbocharged engine as an external heat source to recover heat from the external heat source; an ammonia decomposition hydrogen production subsystem connected to the waste heat recovery subsystem, obtaining heat from the external heat source to preheat the incoming liquid ammonia, and utilizing the preheated ammonia to perform an ammonia decomposition reaction; a fuel cell subsystem connected to the ammonia decomposition hydrogen production subsystem, receiving hydrogen produced from the ammonia decomposition hydrogen production subsystem, using the received hydrogen and air as reaction raw materials to perform an electrochemical reaction based on a proton exchange membrane fuel cell to generate electricity, using heat generated by the burner reaction to preheat the received air, provide heat for the ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem, and transmit the heat to the waste heat recovery subsystem for heat recovery; The ammonia decomposition hydrogen production subsystem comprises: The ammonia decomposition unit is connected to the external ammonia gas, performs high-temperature decomposition on the connected ammonia gas, and preheats the connected ammonia gas by the high-temperature gas connected to the waste heat recovery subsystem and the mixed gas obtained by the decomposition; a separation unit connected to the ammonia decomposition unit and the fuel cell subsystem, receiving the mixed gas decomposed in the decomposition unit, performing pressure swing adsorption separation on the mixed gas, delivering the hydrogen separated by pressure swing adsorption to the proton exchange membrane fuel cell subsystem, and cooling and compressing the ammonia separated by pressure swing adsorption and delivering it to the separation unit; The ammonia decomposition unit includes a first heat exchanger, a second heat exchanger and an ammonia decomposition reactor connected in sequence, and the separation unit includes a pressure swing adsorption separator, a first cooler, a first compressor and a second cooler connected in sequence; the first heat exchanger is connected to external ammonia, exchanges heat between the connected ammonia and the heat source of the waste heat recovery subsystem and then transports it to the second heat exchanger, the second heat exchanger exchanges heat between the connected ammonia and the mixed gas obtained by decomposition in the ammonia decomposition reactor and then transports it to the ammonia decomposition reactor, and the ammonia decomposition reactor transports the mixed gas obtained by decomposition to the second heat exchanger and the pressure swing adsorption separator in sequence; the pressure swing adsorption separator is connected to the fuel cell subsystem, performs pressure swing adsorption separation on the mixed gas obtained by decomposition, transports the hydrogen obtained by pressure swing adsorption separation to the fuel cell subsystem, and transports the ammonia obtained by pressure swing adsorption separation to the first cooler, the first compressor and the second cooler in sequence for cooling and compression, so that the cooled and compressed ammonia and the external ammonia are transported to the first heat exchanger.

2. The power generation system based on ADHP and PEMFC according to claim 1, characterized in that: The waste heat recovery subsystem includes: a pressurizing unit connected to the external heat source, pressurizing the external heat source, and preheating the ammonia gas connected to the ammonia decomposition hydrogen production subsystem through the pressurized heat source; The waste heat recovery unit is connected to the booster unit to recover the heat in the heat source after heat exchange.

3. The power generation system based on ADHP and PEMFC according to claim 2, characterized in that: The boosting unit includes a first turbocharger and a second turbocharger. The first turbocharger is connected to the ammonia decomposition hydrogen production subsystem and the waste heat recovery unit, and can drive the second turbocharger to rotate after rotation; the first turbocharger is connected to the exhaust gas of an external engine, and the connected exhaust gas is supercharged and then transported to the ammonia decomposition hydrogen production subsystem and the waste heat recovery unit in sequence; the second turbocharger is connected to the external air, and the connected air is supercharged and then transported to the ammonia decomposition hydrogen production subsystem.

4. The power generation system based on ADHP and PEMFC according to claim 2, characterized in that: The waste heat recovery unit is an organic Rankine cycle topology, a supercritical carbon dioxide cycle power generation topology or an absorption refrigeration topology.

5. The power generation system based on ADHP and PEMFC according to claim 1, characterized in that: The kinetic model of the ammonia decomposition hydrogen production subsystem is: ， ， in, is the reaction rate of ammonia decomposition reaction, is the reaction constant of the ammonia decomposition reaction, is the pre-exponential factor, E is the activation energy, is the partial pressure of ammonia, is the partial pressure of hydrogen.

6. The power generation system based on ADHP and PEMFC according to claim 1, characterized in that: The fuel cell subsystem comprises: A proton exchange membrane fuel cell having an anode side and a cathode side; a heat exchange unit, connected to the ammonia decomposition hydrogen production subsystem and the cathode side, connected to external air, and heat-exchanging the connected air with the hydrogen produced by the ammonia decomposition hydrogen production subsystem before transporting the heat to the cathode side; a washing unit connected to the heat exchange unit and the anode side, receiving the hydrogen after heat exchange and the hydrogen separated from the mixed gas output from the anode side, making the received hydrogen in a water vapor saturated state and delivering it to the anode side; A combustion unit is connected to the washing unit and the cathode side, receives the mixed gas output from the cathode side, the impurities separated from the mixed gas output from the anode side, and the external air and performs a combustion reaction, and uses the heat generated by the combustion reaction to preheat the air in the heat exchange unit and provide heat for the ammonia decomposition reaction of the ammonia decomposition hydrogen production subsystem.

7. The power generation system based on ADHP and PEMFC according to claim 6, characterized in that: The calculation formula of the cell potential of the proton exchange membrane fuel cell is: ， in, is the battery potential, is the open circuit potential of the battery, For battery overvoltage, is the local current density, is the film thickness, is the membrane conductivity.

8. The power generation system based on ADHP and PEMFC according to claim 6, characterized in that: The heat exchange unit includes a third heat exchanger and a fourth heat exchanger, the scrubbing unit includes a second compressor, a scrubbing device and a separation device, and the combustion unit includes a burner; the third heat exchanger is connected to external air and transports it to the fourth heat exchanger and the inlet of the cathode side in sequence, the ammonia decomposition and hydrogen production subsystem transports the produced hydrogen to the third heat exchanger, the second compressor and the scrubbing device in sequence, the scrubbing device makes the connected hydrogen in a water vapor saturated state and transports it to the anode side, the separation device performs gas separation on the mixed gas output from the outlet of the anode side, and transports the separated hydrogen to the scrubbing device, the burner is connected to the mixed gas output from the outlet of the cathode side, the impurity gas separated by the separation device and the external air and performs a combustion reaction, the heat generated by the combustion reaction is used to heat the ammonia decomposition and hydrogen production subsystem, and the water vapor generated by the combustion reaction is transported to the fourth heat exchanger to preheat the air connected to the inlet of the cathode side.

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