Ammonia-hydrogen internal combustion engine system and control method thereof

Abstract

The invention relates to an ammonia-hydrogen internal combustion engine system and a control method thereof in the technical field of ammonia-hydrogen internal combustion engines, and the ammonia-hydrogen internal combustion engine system comprises an ammonia-hydrogen internal combustion engine, a liquid ammonia tank, a liquid ammonia evaporator, an ammonia decomposition catalyst system, a hydrogen-nitrogen buffer tank and a combustion auxiliary heating module. The hydrogen and nitrogen buffer tank can receive and store gas generated by the ammonia decomposition catalyst system and provide the gas to the combustion auxiliary heating module for combustion. According to the ammonia-hydrogen internal combustion engine system and the control method thereof, the ammonia decomposition catalyst system can be rapidly heated, the starting time of the ammonia-hydrogen internal combustion engine can be shortened, the combustion auxiliary heating module can provide auxiliary heat for ammonia decomposition only in the starting stage of the ammonia-hydrogen internal combustion engine or when the tail gas temperature is low, and the combustion auxiliary heating module can provide auxiliary heat for ammonia decomposition when the tail gas temperature is high. Therefore, the working intensity of the system is reduced, and fuel loss caused by the fact that the combustion auxiliary heating module operates all the time is avoided.

Description

Technical Field

[0001] This application relates to the field of ammonia-hydrogen internal combustion engine technology, and in particular to an ammonia-hydrogen internal combustion engine system and its control method. Background Technology

[0002] The ammonia-hydrogen internal combustion engine is a novel clean power device that uses ammonia as the primary fuel and hydrogen as an auxiliary fuel. Its core technology addresses the shortcomings of pure ammonia combustion through ammonia-hydrogen co-combustion, achieving a balance between zero carbon emissions and high power efficiency. This represents a key technological direction for addressing the energy crisis and environmental pollution. The ammonia-hydrogen internal combustion engine uses ammonia as a hydrogen carrier and hydrogen to assist ammonia combustion, solving the problems of difficult ignition and slow combustion of pure ammonia, while avoiding the risks associated with hydrogen storage. Hydrogen is primarily produced from ammonia through the action of an ammonia decomposition catalyst. For example, Chinese patent CN120312401A – Ammonia-hydrogen engine system and operating method with catalytic combustion-assisted preheating – includes an ammonia decomposition system, a NOx decomposition system, an ammonia-hydrogen engine, a flameless combustion system, an air source, and an ammonia source. It discloses the mixing and combustion of ammonia, hydrogen, nitrogen, and air within the cylinder of the ammonia-hydrogen internal combustion engine, producing high-temperature combustion exhaust gases that provide heat for ammonia decomposition. However, the catalytic combustion-assisted preheating in this patent is constantly in operation, increasing structural stress and maintenance costs, and also causing increased ammonia loss and fuel waste. Summary of the Invention

[0003] In view of the problems existing in the background technology, this application provides an ammonia-hydrogen internal combustion engine system and its control method, which can provide auxiliary heat for ammonia decomposition only during the start-up phase of the ammonia-hydrogen internal combustion engine or when the exhaust gas temperature is low. When the exhaust gas temperature is high, the operation of the combustion auxiliary heating module can be stopped, thereby reducing the system workload and avoiding fuel consumption caused by the continued operation of the combustion auxiliary heating module.

[0004] According to one aspect of the present invention, an ammonia-hydrogen internal combustion engine system is provided, comprising an ammonia-hydrogen internal combustion engine, a liquid ammonia tank, a liquid ammonia evaporator, an ammonia decomposition catalyst system, a hydrogen-nitrogen buffer tank, and a combustion auxiliary heating module; the ammonia decomposition catalyst system is sleeved outside the exhaust pipe of the ammonia-hydrogen internal combustion engine; the liquid ammonia tank is connected to the air inlets of the ammonia-hydrogen internal combustion engine and the ammonia decomposition catalyst system via the liquid ammonia evaporator, and the air outlet of the ammonia decomposition catalyst system is connected to the air inlets of the hydrogen-nitrogen buffer tank and the ammonia-hydrogen internal combustion engine, respectively; the hydrogen-nitrogen buffer tank, the combustion auxiliary heating module, and the exhaust pipe are connected sequentially, and the connection position of the combustion auxiliary heating module and the exhaust pipe is located on the side of the ammonia decomposition catalyst system closer to the ammonia-hydrogen internal combustion engine; the hydrogen-nitrogen buffer tank is capable of receiving and storing the gas generated by the ammonia decomposition catalyst system and providing the gas to the combustion auxiliary heating module for combustion.

[0005] By using the ammonia-hydrogen internal combustion engine system in this technical solution, before starting the ammonia-hydrogen internal combustion engine, hydrogen and nitrogen gas can be introduced into the combustion auxiliary heating module through a hydrogen-nitrogen buffer tank, causing the hydrogen and nitrogen gas to burn and form high-temperature gases in the combustion auxiliary heating module. After the burner is successfully ignited, ammonia gas is introduced into the burner to increase the burner's power. The high-temperature gas heats the ammonia decomposition catalyst system, thereby utilizing the ammonia decomposition catalyst system to partially decompose ammonia gas into hydrogen and nitrogen gas, which is then introduced into the ammonia-hydrogen internal combustion engine for rapid start-up. After the ammonia-hydrogen internal combustion engine has successfully started and the exhaust gas temperature has further increased, the introduction of hydrogen and nitrogen gas from the hydrogen-nitrogen buffer tank into the combustion auxiliary heating module can be stopped, and the operation of the combustion auxiliary heating module can be shut down. This not only rapidly heats the ammonia decomposition catalyst system, shortening the start-up time of the ammonia-hydrogen internal combustion engine, but also allows the combustion auxiliary heating module to be activated only during the start-up phase of the ammonia-hydrogen internal combustion engine to provide auxiliary heat for ammonia decomposition, reducing the system's workload and avoiding fuel consumption caused by continuous operation of the combustion auxiliary heating module.

[0006] In some embodiments of the present invention, the combustion auxiliary heating module includes a burner nozzle, a blower, a combustion fuel injection valve, and a buffer tank outlet shut-off valve; the hydrogen-nitrogen buffer tank, the buffer tank outlet shut-off valve, the combustion fuel injection valve, the burner nozzle, and the exhaust pipe are connected in sequence, and the air outlet of the blower is connected to the air inlet of the burner nozzle.

[0007] In some embodiments of the present invention, the combustion auxiliary heating module further includes a combustion tube connected to the exhaust pipe, and the outlet of the burner nozzle is connected to the combustion tube.

[0008] In some embodiments of the present invention, the combustion auxiliary heating module further includes a combustion chamber shut-off valve, which is disposed inside the combustion tube and located on the side of the burner nozzle outlet near the exhaust pipe.

[0009] In some embodiments of the present invention, the liquid ammonia tank is connected to the burner nozzle, and an ammonia gas shut-off valve is provided between the liquid ammonia tank and the burner nozzle.

[0010] In some embodiments of the present invention, a buffer tank compressor is provided between the ammonia decomposition catalyst system and the hydrogen-nitrogen buffer tank.

[0011] In some embodiments of the present invention, a buffer tank inlet shut-off valve is provided between the buffer tank compressor and the hydrogen-nitrogen buffer tank.

[0012] In some embodiments of the present invention, the ammonia decomposition catalyst system includes an ammonia decomposition heater, an ammonia decomposition catalyst, and a catalytic temperature sensor; the ammonia decomposition heater is sleeved outside the exhaust pipe, and a reaction chamber is formed between the ammonia decomposition heater and the exhaust pipe; the reaction chamber contains the ammonia decomposition catalyst; the inlet of the reaction chamber is connected to the liquid ammonia evaporator, and the outlet is connected to the ammonia-hydrogen internal combustion engine and the hydrogen-nitrogen buffer tank, respectively; the catalytic temperature sensor is used to detect the temperature of the reaction chamber.

[0013] In some embodiments of the present invention, the ammonia-hydrogen internal combustion engine system further includes an SCR system and an ASC system disposed on the exhaust pipe, wherein the SCR system and the ASC system are located on the side of the ammonia decomposition catalyst system near the exhaust pipe outlet.

[0014] According to another aspect of the present invention, a control method for the above-mentioned ammonia-hydrogen internal combustion engine system is provided, comprising the following steps: energizing the ammonia-hydrogen internal combustion engine system; starting the combustion auxiliary heating module and opening the passage from the hydrogen-nitrogen buffer tank to the combustion auxiliary heating module, the gas is burned in the combustion auxiliary heating module, and the high-temperature exhaust gas generated by the combustion enters the exhaust pipe and heats the ammonia decomposition catalyst system; starting the ammonia decomposition catalyst system and feeding ammonia gas from the liquid ammonia tank to the ammonia decomposition catalyst system through the liquid ammonia evaporator, the generated hydrogen-nitrogen gas is supplied to the ammonia-hydrogen internal combustion engine for starting the ammonia-hydrogen internal combustion engine; after the ammonia-hydrogen internal combustion engine is started, the injection amount of ammonia gas into the ammonia-hydrogen internal combustion engine is gradually increased through the liquid ammonia evaporator, the operating time of the combustion auxiliary heating module is determined according to the temperature of the exhaust gas, and a portion of the gas is diverted from the ammonia decomposition catalyst system to replenish the hydrogen-nitrogen buffer tank. Attached Figure Description

[0015] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the ammonia-hydrogen internal combustion engine system of the present invention; Figure 2 This is a flowchart of the control method for the ammonia-hydrogen internal combustion engine system of the present invention.

[0016] The labels in the attached diagram represent the following: 1. Ammonia-hydrogen internal combustion engine; 2. Engine ammonia injection valve; 3. Hydrogen-nitrogen injection valve; 4. Engine coolant outlet pipe; 5. Engine coolant inlet pipe; 6. Liquid ammonia evaporator; 7. Liquid ammonia tank; 8. Ammonia tank gas shut-off valve; 9. Liquid ammonia shut-off valve; 10. Hydrogen-nitrogen buffer tank; 11. Pressure sensor; 12. Buffer tank outlet shut-off valve; 13. Buffer tank inlet shut-off valve; 14. Blower; 15. Burner nozzle; 16. Combustion fuel injection valve; 17. Buffer tank compressor; 18. Hydrogen-nitrogen outlet; 19. Ammonia decomposition heater; 20. Catalytic converter temperature sensor; 21. Ammonia decomposition catalyst; 22. Ammonia inlet; 23. Nitrogen oxide sensor; 24. Exhaust gas ammonia injection valve; 25. SCR system; 26. ASC system; 27. Combustion chamber shut-off valve; 28. Ammonia shut-off valve; 29. ​​Exhaust gas temperature sensor. Detailed Implementation

[0017] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0018] In the following description, when referring to the accompanying drawings, the same numbers in different drawings denote the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0019] In the description of this application, it should be understood that the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, in the description of this application, unless otherwise stated, "multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0020] This application discloses an ammonia-hydrogen internal combustion engine system. For example... Figure 1 As shown, the ammonia-hydrogen internal combustion engine system includes an ammonia-hydrogen internal combustion engine 1, a liquid ammonia tank 7, a liquid ammonia evaporator 6, an ammonia decomposition catalyst system, a hydrogen-nitrogen buffer tank 10, and a combustion auxiliary heating module.

[0021] The ammonia decomposition catalyst system is installed outside the exhaust pipe of the ammonia-hydrogen internal combustion engine 1. The liquid ammonia tank 7 is connected to the air inlet of the ammonia-hydrogen internal combustion engine 1 and the ammonia decomposition catalyst system via the liquid ammonia evaporator 6. The liquid ammonia in the liquid ammonia tank 7 can enter the liquid ammonia evaporator 6 and evaporate into ammonia gas. The ammonia gas can then enter the ammonia-hydrogen internal combustion engine 1 or the ammonia decomposition catalyst system as needed. The exhaust port of the ammonia decomposition catalyst system is connected to the hydrogen-nitrogen buffer tank 10 and the air inlet of the ammonia-hydrogen internal combustion engine 1, respectively. The ammonia gas enters the ammonia decomposition catalyst system from the liquid ammonia evaporator 6 and is catalyzed to produce hydrogen and nitrogen gas (hydrogen and nitrogen). The hydrogen and nitrogen gas can then enter the ammonia-hydrogen internal combustion engine 1 or the hydrogen-nitrogen buffer tank 10 as needed. The hydrogen-nitrogen buffer tank 10, the combustion auxiliary heating module, and the exhaust pipe are connected in sequence, and the connection position of the combustion auxiliary heating module and the exhaust pipe is located on the side of the ammonia decomposition catalyst system closer to the ammonia-hydrogen internal combustion engine 1.

[0022] The hydrogen-nitrogen buffer tank 10 can receive and store the gas produced by the ammonia decomposition catalyst system and provide the gas to the combustion auxiliary heating module for combustion.

[0023] In this invention, before starting the ammonia-hydrogen internal combustion engine 1, hydrogen and nitrogen gas can be introduced into the combustion auxiliary heating module through the hydrogen-nitrogen buffer tank 10, causing the hydrogen and nitrogen gas to burn and form high-temperature gases in the combustion auxiliary heating module. Once the burner is successfully ignited, ammonia gas is introduced into the burner through the ammonia port of the ammonia tank to increase the burner's power. The high-temperature gas flowing through the exhaust pipe heats the ammonia decomposition catalyst system. When the ammonia decomposition catalyst system reaches a certain temperature, ammonia gas can be introduced into it, allowing the ammonia gas to partially decompose into hydrogen and nitrogen gas. This hydrogen and nitrogen gas can then be introduced into the ammonia-hydrogen internal combustion engine 1 for rapid starting. After the ammonia-hydrogen internal combustion engine 1 is successfully started, the injection rate of ammonia gas into the ammonia-hydrogen internal combustion engine 1 can be gradually increased through the liquid ammonia evaporator 6 until the exhaust gas temperature of the ammonia-hydrogen internal combustion engine 1 further increases, satisfying the catalytic effect of the ammonia decomposition catalyst system on the ammonia gas. The requirement is that, at this point, the supply of hydrogen, nitrogen, and ammonia from the hydrogen-nitrogen buffer tank 10 and the liquid ammonia tank 7 to the combustion auxiliary heating module can be stopped, and the operation of the combustion auxiliary heating module can be shut down. Thus, this invention utilizes the hydrogen-nitrogen buffer tank 10 and the liquid ammonia tank 7 in conjunction with the combustion auxiliary heating module, which can not only quickly heat the ammonia decomposition catalyst system and shorten the start-up time of the ammonia-hydrogen internal combustion engine 1, but also activate the combustion auxiliary heating module only during the start-up phase of the ammonia-hydrogen internal combustion engine 1 to provide auxiliary heat for the ammonia decomposition catalyst, reducing the system workload and avoiding fuel consumption caused by the continuous operation of the combustion auxiliary heating module.

[0024] In addition, during the operation of the ammonia-hydrogen internal combustion engine 1, if the exhaust gas temperature is low, the hydrogen-nitrogen buffer tank 10 and the combustion auxiliary heating module can also be turned on. The combustion auxiliary heating module burns hydrogen and nitrogen and discharges the exhaust gas into the exhaust pipe to increase the exhaust gas temperature and provide auxiliary heat for ammonia decomposition, thereby meeting the heating requirements of the ammonia decomposition catalyst system.

[0025] Furthermore, during the normal operation of the ammonia-hydrogen internal combustion engine 1, part of the hydrogen and nitrogen gas produced by the catalytic decomposition of the ammonia decomposition catalyst system can be introduced into the hydrogen and nitrogen gas buffer tank 10 so that sufficient hydrogen and nitrogen gas can be reserved for combustion of the combustion auxiliary heating module during the next start-up phase of the ammonia-hydrogen internal combustion engine 1 or when the exhaust gas temperature is low.

[0026] It should be noted that, since the ammonia decomposition catalyst system does not completely decompose the introduced ammonia gas, the hydrogen-nitrogen gas mentioned in this invention is not a mixture of only hydrogen and nitrogen, but a mixture of at least ammonia. This invention only indicates the mixture of gases by the main target components of catalytic decomposition, that is, by using hydrogen-nitrogen gas to represent the mixture of gases.

[0027] In some embodiments of the present invention, such as Figure 1 As shown, the combustion auxiliary heating module includes a burner nozzle 15, a blower 14, a combustion fuel injection valve 16, and a buffer tank outlet shut-off valve 12.

[0028] The hydrogen-nitrogen buffer tank 10, the buffer tank outlet shut-off valve 12, the combustion fuel injection valve 16, the burner nozzle 15 and the exhaust pipe are connected in sequence, and the air outlet of the blower 14 is connected to the air inlet of the burner nozzle 15.

[0029] In this embodiment, when auxiliary heat is needed for ammonia decomposition, the buffer tank outlet shut-off valve 12 can be opened, allowing the hydrogen-nitrogen buffer tank 10 to inject hydrogen-nitrogen gas into the burner nozzle 15 through the combustion fuel injection valve 16. At the same time, the blower 14 is started to draw air into the burner nozzle 15, and the mixture of hydrogen-nitrogen gas and air is ignited by the spark plug of the burner, thereby forming a high-temperature gas. The high-temperature gas can then be discharged into the tailpipe to provide auxiliary heating for the ammonia decomposition catalyst system.

[0030] In some embodiments of the present invention, such as Figure 1 As shown, the combustion auxiliary heating module also includes a combustion tube, which is connected to the exhaust pipe, and the outlet of the burner nozzle 15 is connected to the combustion tube.

[0031] It should be understood that a combustion chamber is formed inside the combustion tube, with one end connected to the exhaust pipe and the other end connected to the burner nozzle 15. In this embodiment, connecting the burner nozzle 15 to the exhaust pipe via the combustion tube allows the mixture of hydrogen, nitrogen, and air to burn within the combustion chamber before the high-temperature gas enters the exhaust pipe, thus reducing the impact on the exhaust pipe. For example, when the ammonia-hydrogen internal combustion engine 1 starts and exhausts its exhaust gas, burning hydrogen and nitrogen within the combustion chamber can reduce the mutual interference between the two exhaust gases.

[0032] In some embodiments of the present invention, such as Figure 1 As shown, the combustion auxiliary heating module also includes a combustion chamber shut-off valve 27, which is located inside the combustion tube and is situated on the side of the burner nozzle 15 near the exhaust pipe.

[0033] In this embodiment, when no auxiliary heat is needed for ammonia decomposition, i.e., when the burner nozzle 15, blower 14, fuel injection valve 16, and buffer tank outlet shut-off valve 12 are all closed, the combustion chamber shut-off valve 27 can be closed. Cutting off the connection between the burner nozzle 15 and the exhaust pipe reduces damage to the burner (burner nozzle 15) caused by the high-temperature exhaust gas in the exhaust pipe, and also reduces ineffective heat loss of the high-temperature exhaust gas at the combustion auxiliary heating module, thereby improving the heating effect of the high-temperature exhaust gas on the ammonia decomposition catalyst system.

[0034] In some embodiments of the present invention, such as Figure 1 As shown, the liquid ammonia tank 7 is connected to the burner nozzle 15, and an ammonia gas shut-off valve 8 is provided between the liquid ammonia tank 7 and the burner nozzle 15.

[0035] In this embodiment, by connecting the liquid ammonia tank 7 to the burner nozzle 15, after the combustion auxiliary heating module is successfully started, ammonia gas is introduced into the burner nozzle 15 through the liquid ammonia tank 7. The hydrogen and nitrogen gas introduced into the burner nozzle 15 in conjunction with the hydrogen and nitrogen buffer tank 10 can further improve the combustion power, thereby further improving the heating efficiency of the ammonia decomposition catalyst system, and further shortening the start-up time of the ammonia-hydrogen internal combustion engine 1.

[0036] In some embodiments of the present invention, such as Figure 1 As shown, a buffer tank compressor 17 is provided between the ammonia decomposition catalyst system and the hydrogen-nitrogen buffer tank 10.

[0037] In this embodiment, when it is necessary to replenish hydrogen and nitrogen gas to the hydrogen-nitrogen buffer tank 10 by the ammonia decomposition catalyst system, the buffer tank compressor 17 can be turned on to fill the hydrogen-nitrogen buffer tank 10 with gas, and store the high-pressure hydrogen and nitrogen gas for subsequent use.

[0038] Furthermore, a buffer tank inlet shut-off valve 13 is provided between the buffer tank compressor 17 and the hydrogen-nitrogen buffer tank 10.

[0039] In some embodiments of the present invention, such as Figure 1 As shown, a pressure sensor 11 is provided on the hydrogen-nitrogen buffer tank 10, which is used to detect the gas pressure of the hydrogen-nitrogen buffer tank 10 in real time.

[0040] In this embodiment, by setting a pressure sensor 11, it can be used to determine whether to replenish hydrogen and nitrogen gas to the hydrogen-nitrogen buffer tank 10, so as to ensure that the hydrogen-nitrogen buffer tank 10 provides a stable supply of hydrogen and nitrogen gas to the combustion auxiliary heating module.

[0041] In some embodiments of the present invention, such as Figure 1 As shown, the ammonia decomposition catalyst system includes an ammonia decomposition heater 19, an ammonia decomposition catalyst 21, and a catalytic temperature sensor 20.

[0042] The ammonia decomposition heater 19 is installed outside the exhaust pipe, and a reaction chamber is formed between the ammonia decomposition heater 19 and the exhaust pipe. The reaction chamber contains the ammonia decomposition catalyst 21. The inlet of the reaction chamber is connected to the liquid ammonia evaporator 6, and the outlet is connected to the ammonia-hydrogen internal combustion engine 1 and the hydrogen-nitrogen buffer tank 10, respectively. The catalytic temperature sensor 20 is used to detect the temperature of the reaction chamber.

[0043] In this embodiment, the liquid ammonia in the liquid ammonia tank 7 is evaporated by the liquid ammonia evaporator 6 and then enters the reaction chamber. The reaction chamber is heated by the ammonia decomposition heater 19 and the exhaust gas in the tailpipe. The ammonia is catalyzed by the ammonia decomposition catalyst 21 in the reaction chamber to produce hydrogen and nitrogen, which are then used to start the ammonia-hydrogen internal combustion engine 1 or to replenish the hydrogen-nitrogen buffer tank 10. A catalytic temperature sensor 20 is installed in the reaction chamber to detect its temperature, allowing for real-time monitoring. Based on changes in the catalytic temperature and actual operating conditions, the timing of introducing ammonia from the liquid ammonia evaporator 6 into the reaction chamber, and the timing of introducing hydrogen and nitrogen from the reaction chamber into the ammonia-hydrogen internal combustion engine 1 or the hydrogen-nitrogen buffer tank 10, can be selected, or the timing of shutting off the introduction of ammonia from the liquid ammonia evaporator 6 into the reaction chamber, and the introduction of hydrogen and nitrogen from the reaction chamber into the ammonia-hydrogen internal combustion engine 1 or the hydrogen-nitrogen buffer tank 10, can be selected.

[0044] In some embodiments of the present invention, such as Figure 1 As shown, the reaction chamber is equipped with a hydrogen-nitrogen outlet 18 and an ammonia inlet 22. The liquid ammonia evaporator 6 is connected to the ammonia inlet 22 through a pipeline. The hydrogen-nitrogen outlet 18 is connected to the ammonia-hydrogen internal combustion engine 1 through a hydrogen-nitrogen injection valve 3.

[0045] In some embodiments of the present invention, such as Figure 1 As shown, an exhaust gas temperature sensor 29 for detecting exhaust gas temperature is provided on the side of the exhaust pipe near the ammonia-hydrogen internal combustion engine 1, which is located on the ammonia decomposition catalyst system.

[0046] In this embodiment, the exhaust gas temperature sensor 29 can detect the temperature of the exhaust gas (corresponding to the reaction chamber) passing through the exhaust pipe in real time. This allows the sensor to select the timing for introducing ammonia into the ammonia decomposition catalyst system before the ammonia-hydrogen internal combustion engine 1 starts, based on the heating status of the ammonia decomposition catalyst system by the combustion auxiliary heating module. Alternatively, after the ammonia-hydrogen internal combustion engine 1 starts, the sensor can select the timing for turning off the combustion auxiliary heating module based on the heating status of the ammonia decomposition catalyst system by the exhaust gas. Furthermore, when the exhaust gas temperature is too low during the operation of the ammonia-hydrogen internal combustion engine 1, the sensor can appropriately turn on the combustion auxiliary heating module to assist in heating the ammonia decomposition catalyst system.

[0047] In some embodiments of the present invention, such as Figure 1 As shown, the ammonia-hydrogen internal combustion engine 1 is equipped with an engine ammonia injection valve 2, and the liquid ammonia evaporator 6 is connected to the engine ammonia injection valve 2 through a pipeline. After the ammonia-hydrogen internal combustion engine 1 is successfully started, the engine ammonia injection valve 2 can be opened to inject ammonia into the ammonia-hydrogen internal combustion engine 1, which, together with the input hydrogen and nitrogen, provides power for the operation of the ammonia-hydrogen internal combustion engine 1.

[0048] In some embodiments of the present invention, such as Figure 1 As shown, the ammonia-hydrogen internal combustion engine system also includes an SCR system 25 (Selective Catalytic Reduction system) and an ASC system 26 (Ammonia Purification Catalyst) located on the exhaust pipe. The SCR system 25 and the ASC system 26 are located on the side of the ammonia decomposition catalyst system near the exhaust pipe outlet.

[0049] Furthermore, the liquid ammonia tank 7 is connected to the tail gas pipe via the liquid ammonia evaporator 6 and the tail gas port ammonia injection valve 24 and is located on one side of the air inlet of the SCR system 25.

[0050] In this invention, ammonia gas is introduced into the exhaust pipe using liquid ammonia evaporator 6. The SCR system 25 preferentially reduces NOx in the exhaust gas to harmless N2 and H2O, and the ASC system 26 follows up by treating the unreacted ammonia gas in the SCR system 25, ensuring that both NOx and NH3 meet emission standards. At the same time, before the ammonia-hydrogen internal combustion engine 1 is successfully started, the high-temperature gas generated by the combustion auxiliary heating module can not only quickly heat the ammonia decomposition catalyst system, but also simultaneously and quickly heat the SCR system 25 and the ASC system 26, achieving the effect of catalyzing NOx emission and catalytic decomposition of unburned ammonia gas.

[0051] In some embodiments of the present invention, such as Figure 1 As shown, a nitrogen oxide sensor 23 is installed on the tail gas pipe between the ammonia decomposition catalyst system and the tail gas port ammonia injection valve 24. The NOx concentration is detected by the nitrogen oxide sensor 23, and the amount of ammonia injected into the tail gas pipe by the tail gas port ammonia injection valve 24 can be adjusted according to the detection result to ensure accurate matching between ammonia and tail gas to be treated.

[0052] In some embodiments of the present invention, such as Figure 1 As shown, the ammonia inlet 22 and the tail gas outlet ammonia injection valve 24 can be connected to the liquid ammonia evaporator 6 through an ammonia shut-off valve 28.

[0053] In some embodiments of the present invention, such as Figure 1 As shown, the liquid ammonia evaporator 6 is connected in series in the engine cooling water circuit of the ammonia-hydrogen internal combustion engine 1.

[0054] It should be understood that the liquid ammonia evaporator 6 has a liquid ammonia channel for liquid ammonia flow and a heat exchange chamber for cooling water flow. In this embodiment, the circulating cooling water in the engine cooling water circuit absorbs heat when passing through the ammonia-hydrogen internal combustion engine 1, and then exchanges heat with the liquid ammonia in the liquid ammonia channel when passing through the heat exchange chamber, thereby achieving the synergistic effect of cooling water cooling and liquid ammonia evaporation.

[0055] Specifically, in this embodiment, the liquid ammonia evaporator 6 is connected to the ammonia-hydrogen internal combustion engine 1 through the engine cooling water outlet pipe 4 and the engine cooling water inlet pipe 5.

[0056] In some embodiments of the present invention, such as Figure 1 As shown, a liquid ammonia shut-off valve 9 is provided between the liquid ammonia evaporator 6 and the liquid ammonia tank 7, so as to cut off the supply of liquid ammonia from the liquid ammonia tank 7 to the liquid ammonia evaporator 6 when the ammonia-hydrogen internal combustion engine 1 stops running, and to open the liquid ammonia tank 7 to supply liquid ammonia to the liquid ammonia evaporator 6 when the ammonia-hydrogen internal combustion engine 1 starts.

[0057] This embodiment also proposes a control method for the above-mentioned ammonia-hydrogen internal combustion engine system, which includes the following steps: S1, the ammonia-hydrogen internal combustion engine system is powered on.

[0058] S2. Start the combustion auxiliary heating module and open the passage from the hydrogen-nitrogen buffer tank 10 to the combustion auxiliary heating module. The gas is burned in the combustion auxiliary heating module, and the high-temperature exhaust gas generated by the combustion enters the tail gas pipe and heats the ammonia decomposition catalyst system.

[0059] S3. Start the ammonia decomposition catalyst system and send ammonia gas from the liquid ammonia tank 7 to the ammonia decomposition catalyst system through the liquid ammonia evaporator 6. The generated hydrogen and nitrogen gas are sent to the ammonia-hydrogen internal combustion engine 1 to start the ammonia-hydrogen internal combustion engine 1.

[0060] S4. After the ammonia-hydrogen internal combustion engine 1 starts, the injection amount of ammonia into the ammonia-hydrogen internal combustion engine is gradually increased through the liquid ammonia evaporator. The operating time of the combustion auxiliary heating module is determined according to the temperature of the exhaust gas, and part of the gas is diverted by the ammonia decomposition catalyst system to replenish the hydrogen-nitrogen buffer tank 10.

[0061] In one embodiment of the present invention, such as Figure 2 As shown, the control method for an ammonia-hydrogen internal combustion engine system includes the following steps: 1) Start signal for ammonia-hydrogen internal combustion engine 1.

[0062] 2) Start the buffer tank outlet shut-off valve 12, the combustion fuel injection valve 16 and the blower 14.

[0063] 3) The burner nozzle 15 ignites the hydrogen-nitrogen mixture. After the burner is successfully ignited, the ammonia shut-off valve 8 of the ammonia tank is opened, and ammonia gas is introduced into the burner nozzle 15 to increase the combustion power and to the ammonia decomposition catalyst system.

[0064] 4) When the temperature of the ammonia decomposition catalyst 21 reaches the set temperature, such as 370℃, open the ammonia shut-off valve 28.

[0065] 5) Open the hydrogen-nitrogen injection valve 3 to introduce hydrogen-nitrogen gas into the ammonia-hydrogen internal combustion engine 1 and start the ammonia-hydrogen internal combustion engine 1.

[0066] 6) Check the exhaust gas temperature sensor 29, for example, if it is higher than 450℃.

[0067] 7) Close the buffer tank outlet shut-off valve 12, turn off the blower 14, and close the combustion chamber shut-off valve 27.

[0068] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An ammonia-hydrogen internal combustion engine system, characterized in that, It includes an ammonia-hydrogen internal combustion engine, a liquid ammonia tank, a liquid ammonia evaporator, an ammonia decomposition catalyst system, a hydrogen-nitrogen buffer tank, and a combustion auxiliary heating module; The ammonia decomposition catalyst system is installed outside the exhaust pipe of the ammonia-hydrogen internal combustion engine. The liquid ammonia tank is connected to the air inlet of the ammonia-hydrogen internal combustion engine and the ammonia decomposition catalyst system via the liquid ammonia evaporator. The air outlet of the ammonia decomposition catalyst system is connected to the hydrogen-nitrogen buffer tank and the air inlet of the ammonia-hydrogen internal combustion engine. The hydrogen-nitrogen buffer tank, the combustion auxiliary heating module, and the exhaust pipe are connected in sequence. The connection position of the combustion auxiliary heating module and the exhaust pipe is located on the side of the ammonia decomposition catalyst system closer to the ammonia-hydrogen internal combustion engine. The hydrogen-nitrogen buffer tank can receive and store the gas produced by the ammonia decomposition catalyst system and provide the gas to the combustion auxiliary heating module for combustion.

2. The ammonia-hydrogen internal combustion engine system according to claim 1, characterized in that, The combustion auxiliary heating module includes a burner nozzle, a blower, a combustion fuel injection valve, and a buffer tank outlet shut-off valve; The hydrogen-nitrogen buffer tank, the buffer tank outlet shut-off valve, the combustion fuel injection valve, the burner nozzle, and the exhaust pipe are connected in sequence, and the air outlet of the blower is connected to the air inlet of the burner nozzle.

3. The ammonia-hydrogen internal combustion engine system according to claim 2, characterized in that, The combustion auxiliary heating module also includes a combustion tube, which is connected to the exhaust pipe, and the outlet of the burner nozzle is connected to the combustion tube.

4. The ammonia-hydrogen internal combustion engine system according to claim 3, characterized in that, The combustion auxiliary heating module also includes a combustion chamber shut-off valve, which is located inside the combustion tube and on the side of the burner nozzle outlet near the exhaust pipe.

5. The ammonia-hydrogen internal combustion engine system according to claim 2, characterized in that, The liquid ammonia tank is connected to the burner nozzle, and an ammonia gas shut-off valve is provided between the liquid ammonia tank and the burner nozzle.

6. The ammonia-hydrogen internal combustion engine system according to claim 1, characterized in that, A buffer tank compressor is provided between the ammonia decomposition catalyst system and the hydrogen-nitrogen buffer tank.

7. The ammonia-hydrogen internal combustion engine system according to claim 6, characterized in that, A buffer tank inlet shut-off valve is provided between the buffer tank compressor and the hydrogen-nitrogen buffer tank.

8. The ammonia-hydrogen internal combustion engine system according to claim 1, characterized in that, The ammonia decomposition catalyst system includes an ammonia decomposition heater, an ammonia decomposition catalyst, and a catalytic temperature sensor. The ammonia decomposition heater is fitted outside the exhaust pipe, and a reaction chamber is formed between the ammonia decomposition heater and the exhaust pipe. The reaction chamber contains the ammonia decomposition catalyst. The inlet of the reaction chamber is connected to the liquid ammonia evaporator, and the outlet is connected to the ammonia-hydrogen internal combustion engine and the hydrogen-nitrogen buffer tank, respectively. The catalytic temperature sensor is used to detect the temperature of the reaction chamber.

9. The ammonia-hydrogen internal combustion engine system according to claim 1, characterized in that, The ammonia-hydrogen internal combustion engine system also includes an SCR system and an ASC system located on the exhaust pipe, with the SCR system and ASC system situated on the side of the ammonia decomposition catalyst system near the exhaust pipe outlet.

10. A control method for an ammonia-hydrogen internal combustion engine system as described in any one of claims 1 to 9, characterized in that, Includes the following steps: S1. The ammonia-hydrogen internal combustion engine system is powered on; S2. Start the combustion auxiliary heating module and open the passage from the hydrogen-nitrogen buffer tank to the combustion auxiliary heating module. The gas is burned in the combustion auxiliary heating module, and the high-temperature exhaust gas generated by the combustion enters the tail gas pipe and heats the ammonia decomposition catalyst system. S3. Start the ammonia decomposition catalyst system and send ammonia gas from the liquid ammonia tank to the ammonia decomposition catalyst system through the liquid ammonia evaporator. The generated hydrogen and nitrogen gas are sent to the ammonia-hydrogen internal combustion engine to start the ammonia-hydrogen internal combustion engine. S4. After the ammonia-hydrogen internal combustion engine starts, the injection volume of ammonia into the engine is gradually increased through the liquid ammonia evaporator. The operating time of the combustion auxiliary heating module is determined based on the temperature of the exhaust gas, and a portion of the gas is diverted by the ammonia decomposition catalyst system to replenish the hydrogen-nitrogen buffer tank.

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