Ammonia internal combustion engine system and control method thereof

Abstract

The application discloses an ammonia internal combustion engine system and a control method thereof, and relates to the field of internal combustion engine systems, and aims at solving the problems of low ammonia hydrogen production efficiency and large equipment volume in the prior art.The ammonia internal combustion engine system comprises an ammonia online decomposition device, a combustion chamber, a purification device and a control system, wherein the ammonia online decomposition device comprises a plurality of electric heating catalytic units, is used for decomposing ammonia fuel into mixed gas containing ammonia, hydrogen and nitrogen, and the number of the electric heating catalytic units is determined according to the maximum ammonia decomposition hydrogen production amount; the combustion chamber is suitable for combusting the mixed gas after premixing with air; the purification device is suitable for purifying unburned ammonia and nitrogen oxides generated by the combustion chamber; and the control system is used for adjusting the power-on number and heating temperature of the electric heating catalytic units according to the hydrogen-ammonia ratio required for ignition and combustion supporting of the combustion chamber.

Description

Technical Field

[0001] This invention relates to the field of internal combustion engine technology, and more specifically to an ammonia internal combustion engine system and its control method. Background Technology

[0002] Ammonia produces low heat during combustion, but it has a high octane rating and good anti-knock properties. Furthermore, the heat loss during ammonia combustion is far lower than that of fuels such as hydrogen, gasoline, and diesel. Therefore, direct combustion of ammonia or its co-combustion with conventional fuels in generators and engines is beneficial for building clean power and clean transportation systems.

[0003] Therefore, ammonia-hydrogen fusion zero-carbon fuel technology can overcome the shortcomings of hydrogen energy alone in terms of transportation, storage, vehicle operation, safety, and cost.

[0004] Existing technology includes a Chinese patent document (CN102089237A) proposing a hydrogen production scheme that utilizes a hydrogen-producing substance that reacts with ammonia to generate hydrogen at low temperatures, then mixes it with ammonia, and finally uses a high-temperature heat source and a metal containing an ammonia decomposition catalyst to decompose the ammonia into hydrogen and nitrogen, which are then mixed with ammonia again. This scheme generates hydrogen at different temperatures and then performs secondary hydrogen-ammonia mixing, resulting in a complex system and large equipment size. Another Chinese patent document (CN102272424A) proposes using a plasma spark plug to directly ignite ammonia, but this scheme does not change the combustion characteristics of ammonia during continuous combustion. Japanese Patent Application Publication No. 5-332152 proposes an ammonia combustion internal combustion engine with an ammonia decomposition reaction unit and a hydrogen storage alloy, utilizing the exhaust heat from the combustion of ammonia in the internal combustion engine to decompose the ammonia. This scheme uses an alloy for hydrogen storage, which increases the system weight, and the control of hydrogen absorption and release rates in alloy hydrogen storage is complex, resulting in high power consumption. Summary of the Invention

[0005] To address the issues of low ammonia decomposition efficiency in existing ammonia internal combustion engines and the complexity and large size of the system caused by the need for pre-production, storage, and blending of hydrogen, this solution proposes an ammonia internal combustion engine system and its control method. By real-time control of the number of energized units and the heating temperature of the electrically heated catalytic unit, online ammonia decomposition and hydrogen production with an adjustable ammonia-to-hydrogen ratio are achieved, enabling ignition and combustion assistance in the combustion chamber. The system has a compact structure, small equipment size, and high ammonia decomposition efficiency.

[0006] According to a first aspect of the present invention, an ammonia internal combustion engine system is provided, comprising: an online ammonia decomposition device, a combustion chamber, a purification device, and a control system.

[0007] The online ammonia decomposition unit includes multiple electrically heated catalytic units for decomposing ammonia fuel into a mixture of ammonia, hydrogen, and nitrogen. The number of electrically heated catalytic units is determined based on the maximum hydrogen production from ammonia decomposition. The combustion chamber is suitable for pre-mixing the mixture with air before combustion. The purification device is suitable for purifying unburned ammonia and NOx generated in the combustion chamber. The control system is used to adjust the number of electrically heated catalytic units and their heating temperature according to the hydrogen-ammonia ratio required for combustion chamber ignition and combustion support.

[0008] Optionally, the ammonia internal combustion engine system provided by the present invention further includes a flow meter, a pressure sensor, a pipeline temperature sensor, a temperature sensor for multiple electrically heated catalytic units, a hydrogen sensor, an ammonia flow regulating valve, and an air flow regulating valve.

[0009] The ammonia flow regulating valve and the air flow regulating valve are respectively installed at the ammonia inlet and the air inlet of the combustion chamber of the online ammonia decomposition device, and are used to regulate the ammonia flow and the air flow respectively; The flow meter is installed between the flow regulating valve and the online ammonia decomposition device to measure the ammonia gas delivery flow rate; Pressure sensors, pipeline temperature sensors, and hydrogen sensors are installed on the exhaust pipeline of the online ammonia decomposition device to monitor the pipeline exhaust pressure, the gas temperature inside the pipeline, and the purity of hydrogen after ammonia decomposition, respectively. Temperature sensors for multiple electrically heated catalytic units are installed on the online ammonia decomposition device to monitor the temperature of the multiple electrically heated catalytic units.

[0010] Optionally, in the ammonia internal combustion engine system provided by the present invention, the control system is adapted to collect data signals from multiple electric heating catalytic unit temperature sensors, pipeline temperature sensors, hydrogen sensors, and pressure sensors.

[0011] Optionally, in the ammonia internal combustion engine system provided by the present invention, the control system can send flow control signals to the ammonia flow regulating valve and the air flow regulating valve according to the air-fuel ratio requirements of the combustion chamber; adjust the energizing ratio of the electric heating catalytic unit according to the hydrogen sensor signal and the hydrogen ratio setting value; and control the current of the electric heating catalytic unit according to the temperature sensor signal and the temperature setting value.

[0012] Optionally, in the ammonia internal combustion engine system provided by the present invention, the ammonia online decomposition device includes a left end plate, multiple sets of electrically heated catalytic units, a heat insulation layer, an insulating layer, a right end plate connected by a screw structure, and a gas inlet channel and a gas outlet channel disposed on the left end plate, multiple sets of electrically heated catalytic units, heat insulation layer, insulating layer, and right end plate.

[0013] Optionally, in the ammonia internal combustion engine system provided by the present invention, the electrically heated catalytic unit includes an insulation layer, an insulating layer, and alternatingly stacked flat plates and flow channel plates, and electrically connected terminals located on both sides of the flat plates and flow channel plates. The flat plates and flow channel plates are provided with gas inlets and gas outlets. The flat plates include electrically heatable metal plates and catalyst coatings sprayed on the surface of the metal plates. The flow channel plates include metal plates with flow channels and catalyst coatings sprayed on the surface of the metal plates. The flow channel plates and flat plates are simultaneously electrically heated through the electrically connected terminals on both sides of the plates.

[0014] Optionally, in the ammonia internal combustion engine system provided by the present invention, the electrically heated catalytic unit is powered by the internal combustion engine or by an external power source.

[0015] According to a second aspect of the present invention, a control method for an ammonia internal combustion engine system is provided, comprising: configuring the number of electrically heated catalytic units in an online ammonia decomposition device according to the maximum ammonia decomposition amount; During the ammonia decomposition process, the data signals transmitted by the temperature sensor of the electric heating catalytic unit, the pipeline temperature sensor, the hydrogen sensor, and the pressure sensor are monitored in real time. Based on the combustion chamber's requirement for air-fuel ratio, control signals to adjust the flow rate are sent to the ammonia flow regulating valve and the air flow regulating valve. Based on the ammonia-hydrogen ratio requirements during combustion chamber ignition and combustion support, the contactor of the online ammonia decomposition device is given an on / off signal to control the energization ratio and heating temperature of the electrically heated catalytic unit.

[0016] Optionally, in the control method of the above-mentioned ammonia internal combustion engine system, the energization ratio of the electric heating catalytic unit is allocated according to the different hydrogen and ammonia ratio values ​​required for ignition and combustion assistance in the combustion chamber. The heating temperature of the electrically heated catalytic unit is adjusted according to the different hydrogen and ammonia ratios required for ignition and combustion support in the combustion chamber. The hydrogen purity signal from the hydrogen sensor after ammonia decomposition is compared with the set value of the hydrogen ratio, and the power supply ratio of the electric heating catalytic unit is adjusted accordingly. The current of the electrically heated catalytic unit is controlled based on the temperature signal from the temperature sensor and the temperature setpoint.

[0017] According to the present invention, the proportion of hydrogen produced by online ammonia decomposition is controlled in real time by controlling the number of energized electric heating catalytic units and the heating temperature, thereby realizing the ignition and combustion assistance of the combustion chamber. The system has a compact structure, small equipment size, and high ammonia decomposition efficiency.

[0018] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0019] 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 invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic diagram of the online hydrogen production, blending, and combustion process of an ammonia internal combustion engine system according to an embodiment of the present invention is shown; Figure 2 A schematic diagram of an online ammonia decomposition device according to an embodiment of the present invention is shown; Figure 3 A schematic diagram of the structure of an electroheated catalytic unit according to an embodiment of the present invention is shown; Figure 4 A schematic diagram of the control structure of an ammonia internal combustion engine system according to an embodiment of the present invention is shown; Figure 5 A flowchart illustrating a control method for an ammonia internal combustion engine system according to an embodiment of the present invention is shown. Detailed Implementation

[0020] Ammonia decomposition for hydrogen production is a chemical reaction in which ammonia gas decomposes at a certain temperature under the action of a nickel-based catalyst, i.e., 2NH3 = N2 + 3H2. If the ammonia decomposition rate reaches 50%, the hydrogen, nitrogen, and gaseous ammonia synthesis gas obtained from the decomposition will contain 50% hydrogen by volume. If the ammonia decomposition rate reaches 100%, it can decompose into a hydrogen-nitrogen synthesis gas containing 75% H2 and 25% N2. The higher the ammonia decomposition rate, the higher the hydrogen content.

[0021] Currently, the efficiency and economy of ammonia internal combustion engines remain the biggest challenges. To address the problems of poor economic efficiency in storing and transporting hydrogen required for blending in existing ammonia internal combustion engines, the complexity of systems that require hydrogen storage before blending, and the large size of ammonia decomposition hydrogen production equipment, this solution proposes an ammonia internal combustion engine system and its control method. By controlling the number of ammonia decomposition hydrogen production channels and the heating temperature, online ammonia decomposition hydrogen production is achieved, and the ammonia-hydrogen blending ratio is adjustable in real time. The system has a compact structure, small size, and high ammonia decomposition efficiency, effectively realizing ignition and combustion assistance in the combustion chamber of the ammonia internal combustion engine.

[0022] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0023] Figure 1A schematic diagram of the online hydrogen production, blending, and combustion process of an ammonia internal combustion engine system according to an embodiment of the present invention is shown. Figure 1 As shown, the ammonia internal combustion engine system includes an online ammonia decomposition device 3, a combustion chamber 7, a purification device 10, and a control system 11.

[0024] Ammonia fuel enters the online ammonia decomposition unit 3 and is decomposed into a mixture containing ammonia, hydrogen, and nitrogen. The online ammonia decomposition unit 3 includes multiple electrically heated catalytic units, the number of which is determined by the maximum ammonia decomposition hydrogen production capacity. Different maximum ammonia decomposition hydrogen production capacities can be achieved by configuring different numbers of electrically heated catalytic units.

[0025] The mixture of air, ammonia, hydrogen, and nitrogen enters combustion chamber 7 for pre-mixing and combustion. If the ammonia is fully combusted, theoretically only nitrogen and water will be produced. However, in reality, unburned ammonia and nitrogen oxides (NOx) remain. Therefore, a purification device 10 is installed in the exhaust passage of the combustion chamber to purify the unburned ammonia and the nitrogen oxides produced in the combustion chamber.

[0026] The control system 11 can adjust the number of energized units and the heating temperature of the electric heating catalytic unit according to the different ammonia-hydrogen ratios required for ignition and combustion in the combustion chamber 7.

[0027] In addition, such as Figure 1 As shown, the ammonia internal combustion engine system also includes a flow meter 2, a pressure sensor 4, a pipeline temperature sensor 5, multiple electric heating catalytic unit temperature sensors 9, a hydrogen sensor 6, an ammonia flow regulating valve 1, and an air flow regulating valve 8.

[0028] The ammonia flow regulating valve 1 and the air flow regulating valve 8 are respectively installed at the ammonia inlet and the air inlet of the combustion chamber of the online ammonia decomposition device 3, and are used to regulate the ammonia flow and air flow, respectively. The flow meter 2 is installed between the flow regulating valve 1 and the online ammonia decomposition device 3 to measure the ammonia delivery flow.

[0029] Pressure sensor 4, pipeline temperature sensor 5, and hydrogen sensor 6 are respectively installed on the exhaust pipeline of the online ammonia decomposition device 3 to monitor the pipeline exhaust pressure, pipeline exhaust temperature, and the purity of hydrogen after ammonia decomposition. The hydrogen purity provides feedback on the ammonia concentration in the combustible mixture. Multiple electrically heated catalytic unit temperature sensors 9 are installed on the surface of the online ammonia decomposition device 3 to monitor the temperature of multiple electrically heated catalytic units.

[0030] The control system 11 is adapted to collect data signals from multiple temperature sensors of the electrically heated catalytic unit, pipeline temperature sensors, hydrogen sensors, and pressure sensors. Based on the air-fuel ratio requirements of the combustion chamber, it sends flow control signals to the ammonia flow regulating valve and the air flow regulating valve. It adjusts the energizing ratio of the electrically heated catalytic unit based on the hydrogen sensor signal and the hydrogen ratio setpoint, and controls the current of the electrically heated catalytic unit based on the temperature sensor signal and the temperature setpoint.

[0031] The ammonia decomposition reaction within the electric heating catalytic unit is controlled by adjusting the on / off state of the contactors of different electric heating catalytic units in the control system.

[0032] like Figure 1 As shown, the online hydrogen production, blending, and combustion process of an ammonia internal combustion engine specifically includes: ammonia product gas is transported to an online ammonia decomposition device through a pipeline. The pipeline is equipped with: 1. an ammonia flow regulating valve to adjust the ammonia flow rate according to the ammonia intake demand; 2. a flow meter to measure the ammonia delivery flow rate; and 3. an online ammonia decomposition device, in which the ammonia is electrically heated to increase its operating temperature and then decomposed into a combustible mixture of ammonia, hydrogen, and nitrogen after a catalytic reaction with the internal catalyst. At the same time, the online ammonia decomposition device can actively adjust the ammonia decomposition amount by changing the number of energized electric heating catalytic units. The combustible mixture is connected to the fuel inlet of combustion chamber 7 via a pipeline. A hydrogen sensor 4 is installed on the connecting pipeline to monitor the purity of hydrogen after ammonia decomposition. The hydrogen purity can be used to provide feedback on the ammonia concentration in the mixture. A pressure sensor 5 and a pipeline temperature sensor 6 are also installed to monitor the exhaust pressure and temperature.

[0033] The online ammonia decomposition unit is also equipped with multiple temperature sensors for the 9 electrically heated catalytic units. Air is continuously supplied through the air inlet of the 7 combustion chamber. The mixture of gas and air is premixed and then combusted in the 7 combustion chamber. Finally, the unburned ammonia and nitrogen oxides produced in the combustion chamber are purified by the 10 purification device.

[0034] The online ammonia decomposition device provided in this embodiment of the invention includes a left end plate, multiple sets of electrically heated catalytic units, a heat insulation layer, an insulating layer, a right end plate connected by a screw structure, and a gas inlet channel and a gas outlet channel disposed on the left end plate, multiple sets of electrically heated catalytic units, heat insulation layer, insulating layer, and right end plate.

[0035] Figure 2 A schematic diagram of an online ammonia decomposition device according to an embodiment of the present invention is shown. Figure 2As shown, the ammonia online decomposition device 3 specifically includes: a left nut 301, a left washer 302, a screw 303, a screw insulating sleeve 3031, a left end plate 304, a gas inlet 305, multiple sets of electric heating and catalytic units 307, an insulating layer 309, a heat insulation layer 310, a right end plate 311, a right washer 312, a right nut 313, and a gas outlet 314.

[0036] Among them, the heat insulation layer 310 is made of heat insulation material that can adapt to ammonia gas, and the insulation layer 309 is made of insulation material to prevent the conductor from contacting the outside world and causing accidents such as leakage, short circuit, and electric shock.

[0037] The electrically heated catalytic unit includes an insulating layer, a heat insulation layer, and alternatingly stacked flat plates and flow channel plates, with electrically conductive terminals located on both sides of the flat plates and flow channel plates. Gas inlets and gas outlets are provided on the flat plates and flow channel plates. The flat plate includes an electrically heatable metal plate and a catalyst coating sprayed onto its surface; the flow channel plate includes a metal plate with flow channels and a catalyst coating sprayed onto its surface; both the flow channel plate and the flat plate are simultaneously heated by electricity through the electrically conductive terminals on both sides of the plates.

[0038] Figure 3 A schematic diagram of an electrically heated catalytic unit according to an embodiment of the present invention is shown. Figure 3 As shown, the electric heating and catalytic unit 307 specifically includes an insulating layer 309, a heat insulation layer 310, flow channel plates 3071 and 3073, a flat plate 3072, and power terminals 3074 and 3075 (3075 is on the opposite side of 3074). Figure 3 (Not shown in the image).

[0039] The flow channel plates 3071 and 3073 and the flat plate 3072 are simultaneously heated by energizing terminals 3074 and 3075 on both sides of the plate to ensure the temperature required for ammonia catalysis. The number of electrically heated catalytic units can be adjusted according to the scale of ammonia decomposition for hydrogen production in the unit.

[0040] Before ammonia decomposition, the corresponding number of electric heating and catalytic units 307 are configured according to the maximum ammonia decomposition amount. Then, according to the requirements of the combustion chamber for the hydrogen-ammonia ratio, the on / off state of the contactors of different electric heating and catalytic units is adjusted in the control system to control the occurrence of ammonia decomposition reaction in the electric heating and catalytic units.

[0041] The electric heating catalytic unit can be powered by the internal combustion engine's self-generated electricity or by external power. After the electric heating starts working, the temperature inside the entire device reaches the reaction temperature of 500~800℃. Then, gaseous ammonia is introduced into the inlet of the online ammonia decomposition device. It flows along the reaction channel inside the device and undergoes a decomposition reaction under the action of the reaction temperature and the catalyst on the square wave support plate. The generated ammonia / hydrogen mixture is discharged from the outlet.

[0042] Figure 4A schematic diagram of the control structure of an ammonia internal combustion engine system according to an embodiment of the present invention is shown. Figure 4 As shown, the control system collects data signals from temperature sensors, hydrogen sensors, and pressure sensors installed on the exhaust pipe of the ammonia decomposition device to monitor hydrogen purity (degree of ammonia decomposition), exhaust pressure, and exhaust temperature. Simultaneously, based on the air-fuel ratio requirements of the internal combustion engine's combustion chamber, the control system sends control signals to the ammonia flow regulating valve and the air flow regulating valve to adjust the flow rate. Furthermore, based on the hydrogen-ammonia ratio requirements of the internal combustion engine's combustion chamber, the control system sends on / off signals to the contactor of the ammonia decomposition device to control the operating state of the electrically heated catalytic unit, thereby adjusting the amount of ammonia decomposed and achieving online control of the hydrogen-ammonia ratio.

[0043] Figure 5 A schematic flowchart of a control method for an ammonia internal combustion engine system according to an embodiment of the present invention is shown. Figure 5 As shown, firstly, the number of electrically heated catalytic units in the online ammonia decomposition device is configured according to the maximum ammonia decomposition rate.

[0044] Subsequently, during the ammonia decomposition process, data signals transmitted by the temperature sensors of the electrically heated catalytic unit, pipeline temperature sensors, hydrogen sensors, and pressure sensors are monitored in real time to monitor the degree of ammonia decomposition, exhaust temperature, exhaust pressure, etc.

[0045] Based on the combustion chamber's requirement for air-fuel ratio, control signals to adjust the flow rate are sent to the ammonia flow regulating valve and the air flow regulating valve. Based on the combustion chamber's requirement for the ammonia-hydrogen ratio, an on / off signal is sent to the contactor of the online ammonia decomposition device to control the energizing ratio and heating temperature of the electrically heated catalytic unit, thereby adjusting the amount of ammonia decomposed and achieving real-time control of the ammonia-hydrogen ratio.

[0046] Specifically, the energizing ratio of the electrically heated catalytic unit is allocated according to the different hydrogen and ammonia ratios required for ignition and combustion support in the combustion chamber. That is, the energizing ratio of the electrically heated catalytic unit is first coarsely adjusted.

[0047] The heating temperature of the electrically heated catalytic converter is adjusted according to the different hydrogen and ammonia ratios required for ignition and combustion assistance in the combustion chamber. In other words, the heating temperature of the electrically heated catalytic converter is fine-tuned based on a coarse adjustment.

[0048] During ammonia decomposition, the hydrogen purity signal from the hydrogen sensor after ammonia decomposition is compared with the set value of the hydrogen ratio to adjust the energizing ratio of the electrically heated catalytic unit. Based on the temperature signal from the temperature sensor of the electrically heated catalytic unit and the set temperature value, the current of the electrically heated catalytic unit is controlled. This allows for real-time automatic control of the ammonia-to-hydrogen ratio.

[0049] The ammonia internal combustion engine system provided by the present invention achieves online ammonia decomposition hydrogen production and real-time adjustable ammonia-hydrogen blending ratio by controlling the number of ammonia decomposition hydrogen production channels and heating temperature. The system has a compact structure, small size, and high ammonia decomposition efficiency, and can effectively realize the ignition and combustion assistance of the combustion chamber of the ammonia internal combustion engine, solving the problem of complex system equipment and large size caused by hydrogen production, storage and blending.

[0050] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0051] Similarly, it should be understood that, in order to streamline this disclosure and aid in understanding one or more of the various aspects of the invention, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0052] Those skilled in the art will understand that modules, units, or components of the devices disclosed in the examples herein can be arranged in the devices described in this embodiment, or alternatively, can be located in one or more devices different from the devices in this example. The modules in the foregoing examples can be combined into a single module or, in addition, can be divided into multiple sub-modules.

[0053] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0054] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0055] Furthermore, some of the embodiments described herein are methods or combinations of method elements that can be implemented by a processor of a computer system or by other means of performing functions. Therefore, a processor having the necessary instructions for implementing a method or method element forms a means for implementing that method or method element. Furthermore, the elements of the apparatus embodiments herein are examples of means for implementing functions performed by elements for the purposes of carrying out the invention.

[0056] As used herein, unless otherwise specified, the use of ordinal numbers such as “first,” “second,” “third,” etc., to describe ordinary objects merely indicates different instances of similar objects and is not intended to imply that the objects being described must have a given order in time, space, ordering, or any other manner.

[0057] Although the invention has been described with respect to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and edibility purposes, and not for the purpose of interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the invention is illustrative rather than restrictive, and the scope of the invention is defined by the appended claims.

Claims

1. An ammonia internal combustion engine system, characterized in that, include: Ammonia online decomposition unit, combustion chamber, purification unit and control system, The online ammonia decomposition device is used to decompose ammonia fuel into a mixture containing ammonia, hydrogen, and nitrogen; the combustion chamber is adapted to premix the mixture with air before combustion; the purification device is adapted to purify unburned ammonia and nitrogen oxides produced in the combustion chamber; the number of electrically heated catalytic units is determined according to the maximum ammonia decomposition hydrogen production capacity; Each of the electrically heated catalytic units includes a heat insulation layer, an insulating layer, and alternatingly stacked flat plates and flow channel plates, and electrically connected terminals located on both sides of the flat plates and flow channel plates. The flat plates and flow channel plates are provided with gas inlets and gas outlets. The flat plates include electrically heatable metal plates and catalyst coatings sprayed on the surface of the metal plates. The flow channel plates include metal plates with flow channels and catalyst coatings sprayed on the metal surface. The flow channel plate and the plate are simultaneously electrically heated through the electrical terminals on both sides of the plate, so that ammonia gas undergoes a catalytic decomposition reaction in the electrically heated catalytic unit. The ammonia internal combustion engine system also includes a pressure sensor, a pipeline temperature sensor, temperature sensors for multiple sets of electrically heated catalytic units, a hydrogen sensor, an ammonia flow regulating valve, and an air flow regulating valve. The control system is used to collect data signals in real time from temperature sensors, pipeline temperature sensors, hydrogen sensors, and pressure sensors of multiple electrically heated catalytic units during the ammonia decomposition process; to send control signals to adjust the flow rate to the ammonia flow regulating valve and the air flow regulating valve according to the air-fuel ratio requirements of the combustion chamber; and to send on / off signals to the contactor of the online ammonia decomposition device according to the hydrogen-to-ammonia ratio requirements during combustion chamber ignition and combustion assistance, so as to control the working state of the electrically heated catalytic units, allocate the energization ratio of the electrically heated catalytic units, and adjust the heating temperature of the electrically heated catalytic units to adjust the amount of ammonia decomposition. The control system is also used to compare the hydrogen purity signal from the hydrogen sensor after ammonia decomposition with the hydrogen ratio set value to adjust the energization ratio of the electrically heated catalytic units, and to control the current of the electrically heated catalytic units according to the temperature signal from the temperature sensor and the temperature set value, thereby achieving online control of the hydrogen-to-ammonia ratio.

2. The ammonia internal combustion engine system according to claim 1, characterized in that, The ammonia internal combustion engine system also includes a flow meter. The ammonia flow regulating valve and the air flow regulating valve are respectively installed at the ammonia inlet and the air inlet of the combustion chamber of the online ammonia decomposition device, and are used to regulate the ammonia flow and the air flow respectively. The flow meter is installed between the flow regulating valve and the online ammonia decomposition device to measure the ammonia delivery flow rate; The pressure sensor, pipeline temperature sensor, and hydrogen sensor are installed on the exhaust pipeline of the online ammonia decomposition device and are used to monitor the pipeline exhaust pressure, pipeline exhaust temperature, and hydrogen purity after ammonia decomposition, respectively. The multiple temperature sensors for the electro-heated catalytic units are installed on the online ammonia decomposition device to monitor the temperature of the multiple electro-heated catalytic units.

3. The ammonia internal combustion engine system according to claim 1, characterized in that, The online ammonia decomposition device includes a left end plate, multiple sets of electrically heated catalytic units, a heat insulation layer, an insulating layer, a right end plate connected by a screw structure, and a gas inlet channel and a gas outlet channel disposed on the left end plate, multiple sets of electrically heated catalytic units, heat insulation layer, insulating layer, and right end plate.

4. The ammonia internal combustion engine system according to claim 1, characterized in that, The electrically heated catalytic unit is powered by an internal combustion engine or by an external power source.

5. A control method for an ammonia internal combustion engine system, characterized in that, The ammonia internal combustion engine system includes an online ammonia decomposition device, a combustion chamber, a purification device, and a control system. The online ammonia decomposition device is used to decompose ammonia fuel into a mixture containing ammonia, hydrogen, and nitrogen. The combustion chamber is adapted to premix the mixture with air before combustion. The purification device is suitable for purifying unburned ammonia and nitrogen oxides produced in the combustion chamber. The number of electrically heated catalytic units is determined according to the maximum ammonia decomposition hydrogen production capacity. Each electrically heated catalytic unit includes a heat insulation layer, an insulating layer, and alternatingly stacked flat plates and flow channels, and electrically connected terminals located on both sides of the flat plates and flow channels. The flat plates and flow channels are provided with gas inlets and gas outlets. The flat plates include electrically heatable metal plates and a catalyst coating sprayed on the surface of the metal plates. The flow channels include metal plates with flow channels and a catalyst coating sprayed on the metal surface. The flow channel plate and the flat plate are simultaneously electrically heated through the power terminals on both sides of the plate to cause the ammonia gas to undergo a catalytic decomposition reaction in the electrically heated catalytic unit; the ammonia internal combustion engine system also includes a pressure sensor, a pipeline temperature sensor, temperature sensors for multiple sets of electrically heated catalytic units, a hydrogen sensor, an ammonia gas flow regulating valve, and an air flow regulating valve; the method includes: The number of electrically heated catalytic units in the online ammonia decomposition device should be configured according to the maximum ammonia decomposition rate. During the ammonia decomposition process, the data signals transmitted by the temperature sensor of the electric heating catalytic unit, the pipeline temperature sensor, the hydrogen sensor, and the pressure sensor are monitored in real time. Based on the combustion chamber's requirement for air-fuel ratio, control signals to adjust the flow rate are sent to the ammonia flow regulating valve and the air flow regulating valve. Based on the required hydrogen-to-ammonia ratio during combustion chamber ignition and combustion support, an on / off signal is sent to the contactor of the online ammonia decomposition device to control the operating state of the electrically heated catalytic unit, allocate the energizing ratio of the electrically heated catalytic unit, and adjust the heating temperature of the electrically heated catalytic unit to adjust the amount of ammonia decomposed. The control system also compares the hydrogen purity signal from the hydrogen sensor after ammonia decomposition with the hydrogen ratio setpoint to adjust the energizing ratio of the electrically heated catalytic unit, and controls the current of the electrically heated catalytic unit based on the temperature signal from the temperature sensor and the temperature setpoint, thereby achieving online control of the hydrogen-to-ammonia ratio.

6. The control method for an ammonia internal combustion engine system according to claim 5, characterized in that, The steps of controlling the working state of the electrically heated catalytic unit, allocating the energizing ratio of the electrically heated catalytic unit, and adjusting the heating temperature of the electrically heated catalytic unit, as required by the hydrogen-to-ammonia ratio, include: The energizing ratio of the electrically heated catalytic unit is allocated according to the different hydrogen and ammonia ratios required for ignition and combustion support in the combustion chamber. The heating temperature of the electrically heated catalytic unit is adjusted according to the different hydrogen and ammonia ratios required for ignition and combustion support in the combustion chamber.

Images