Ammonia fuel combustion system and control method thereof

Abstract

The invention discloses an ammonia fuel combustion system and a control method thereof, and relates to the technical field of fuel combustion. The system comprises an ammonia engine, a reforming hydrogen production device, a preheating box, an ammonia storage device, a premixer and a turbocharger, wherein the reforming hydrogen production device comprises a reaction inner cavity and a heating outer cavity. The premixer mixes gases from the ammonia reservoir, the turbocharger, and the reaction chamber of the reforming hydrogen production unit. The reaction inner cavity of the reforming hydrogen production device is used for carrying out decomposition reaction on ammonia-containing gas from the ammonia storage device and the turbocharger to obtain hydrogen-containing gas, and providing the hydrogen-containing gas to the premixer. A waste gas outlet of the ammonia engine is connected to a heating outer cavity of the reforming hydrogen production device, and the heating outer cavity provides reaction heat for the reaction inner cavity. The heating outer cavity is connected to the preheating box, and the preheating box preheats ammonia-containing gas input into the reaction inner cavity through ammonia engine waste gas from the heating outer cavity. The hydrogen production efficiency can be improved, so that the operation performance of the engine is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel combustion, and in particular to an ammonia fuel combustion system and a control method thereof. Background Art

[0002] At present, the widely used marine engine fuels are mainly diesel and natural gas. At the same time, in order to improve energy utilization and reduce pollutant emissions, ammonia is widely used as a zero-carbon fuel. However, at present, the disadvantage of pure ammonia engines is that they cannot maintain stable operation. Therefore, their operating characteristics can be changed by hydrogen blending and combustion to achieve the required energy output. Hydrogen is generally stored in cylinders at high pressure, but this storage method may cause corrosion and leakage problems. In contrast, the storage of ammonia is safer and more economical. Therefore, ammonia can be used as a hydrogen-carrying gas and hydrogen blending and combustion can be performed through online hydrogen production to improve the operation and ignition of ammonia engines. At present, the devices that use ammonia as a hydrogen-carrying substance to perform thermal catalytic decomposition to prepare fuel hydrogen generally have low heat exchange efficiency, resulting in low hydrogen output and unable to effectively improve the operating performance of ammonia engines. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an ammonia fuel combustion system and a control method thereof, which can improve the hydrogen production efficiency and thus improve the engine operating performance.

[0004] On the one hand, an embodiment of the present invention provides an ammonia fuel combustion system, comprising: an ammonia engine, a reforming hydrogen production device, a preheating box, an ammonia storage, a premixer and a turbocharger, wherein the reforming hydrogen production device comprises a reaction inner chamber and a heating outer chamber;

[0005] The ammonia storage, the turbocharger and the reaction inner cavity of the reforming hydrogen production device are all connected to the premixer through pipelines, and the premixer is connected to the feed port of the ammonia engine through a pipeline. The premixer is used to mix the gases from the ammonia storage, the turbocharger and the reaction inner cavity of the reforming hydrogen production device;

[0006] The ammonia storage and the turbocharger are both connected to the reaction chamber of the reforming hydrogen production device through pipelines, and the reaction chamber of the reforming hydrogen production device is used to decompose the ammonia-containing gas from the ammonia storage and the turbocharger to obtain hydrogen-containing gas, and provide the hydrogen-containing gas to the premixer;

[0007] The exhaust gas outlet of the ammonia engine is connected to the heating outer chamber of the reforming hydrogen production device through a pipeline, and the heating outer chamber of the reforming hydrogen production device is used to provide reaction heat for the reaction inner chamber of the reforming hydrogen production device;

[0008] The heating outer chamber of the reforming hydrogen production device is connected to the preheating box through a pipeline, and the preheating box is used to preheat the ammonia-containing gas input into the reaction inner chamber of the reforming hydrogen production device through the ammonia engine exhaust gas from the heating outer chamber.

[0009] According to some embodiments of the present invention, the reaction chamber of the reforming hydrogen production device includes a top cavity, a bottom cavity and a plurality of pipes, the tops of the plurality of pipes are connected to the top cavity, and the bottoms of the plurality of pipes are connected to the bottom cavity; the plurality of pipes are arranged in the heating outer cavity, and the direction of the pipes is perpendicular to the flow direction of the ammonia engine exhaust gas in the heating outer cavity.

[0010] According to some embodiments of the present invention, the ammonia fuel combustion system also includes a cooling and liquid removal device, which is arranged on a pipeline between the reaction cavity of the reforming hydrogen production device and the premixer, and is used to remove moisture from the hydrogen-containing gas from the reaction cavity.

[0011] According to some embodiments of the present invention, a metal coil is wound around the outside of the reaction chamber of the reforming hydrogen production device.

[0012] According to some embodiments of the present invention, the ammonia fuel combustion system also includes an electric heater, which is arranged on the air inlet pipeline of the reaction chamber of the reforming hydrogen production device, and the electric heater is used to heat the ammonia-containing gas input into the reaction chamber of the reforming hydrogen production device.

[0013] According to some embodiments of the present invention, the ammonia fuel combustion system also includes an exhaust gas treatment device, and the cooling and deliquidation device and the preheating box are both connected to the exhaust gas treatment device through pipelines. The exhaust gas treatment device is used to react the remaining ammonia water mixture in the cooling and deliquidation device and the ammonia engine exhaust gas passing through the preheating box, and discharge the treated tail gas after the reaction.

[0014] According to some embodiments of the present invention, the ammonia storage device is connected to the exhaust gas treatment device through a pipeline, and a pollutant concentration sensor is also provided on the exhaust port of the exhaust gas treatment device.

[0015] According to some embodiments of the present invention, the ammonia fuel combustion system further includes a controller, wherein the controller is configured to:

[0016] Obtain the operating power and operating time of the ammonia engine;

[0017] determining a current operating stage of the ammonia engine according to the operating power and the operating time;

[0018] determining a corresponding ammonia engine fuel requirement and a system operating mode according to the operating stage;

[0019] The corresponding system components are turned on according to the system operating mode, and the operating parameters of the system components are adjusted according to the fuel demand of the ammonia engine, wherein the system components include an ammonia engine, a reforming hydrogen production device, an ammonia storage, a turbocharger, a metal coil power supply device and an electric heater.

[0020] According to some embodiments of the present invention, the ammonia fuel combustion system further includes a controller, wherein the controller is configured to:

[0021] Acquiring a pollutant concentration value through the pollutant concentration sensor;

[0022] When the pollutant concentration value is greater than the concentration threshold, the valve on the pipeline between the ammonia storage device and the exhaust gas treatment device is controlled to open so as to introduce ammonia gas into the exhaust gas treatment device.

[0023] On the other hand, an embodiment of the present invention further provides a control method for an ammonia fuel combustion system, which is applied to the ammonia fuel combustion system of the above embodiment, and the control method comprises the following steps:

[0024] Obtain the operating power and operating time of the ammonia engine;

[0025] determining a current operating stage of the ammonia engine according to the operating power and the operating time;

[0026] determining a corresponding ammonia engine fuel requirement and a system operating mode according to the operating stage;

[0027] The corresponding system components are turned on according to the system operating mode, and the operating parameters of the system components are adjusted according to the fuel demand of the ammonia engine, wherein the system components include an ammonia engine, a reforming hydrogen production device, an ammonia storage, a turbocharger, a metal coil power supply device and an electric heater.

[0028] The above technical solution of the present invention has at least one of the following advantages or beneficial effects: the ammonia fuel combustion system includes an ammonia engine, a reforming hydrogen production device, a preheating box, an ammonia storage, a premixer and a turbocharger, and the reforming hydrogen production device includes a reaction chamber and a heating outer chamber. The premixer mixes the gases from the ammonia storage, the turbocharger and the reaction chamber of the reforming hydrogen production device. The reaction chamber of the reforming hydrogen production device decomposes the ammonia-containing gas from the ammonia storage and the turbocharger to obtain hydrogen-containing gas, and provides the hydrogen-containing gas to the premixer. The exhaust gas outlet of the ammonia engine is connected to the heating outer chamber of the reforming hydrogen production device through a pipeline, and the heating outer chamber of the reforming hydrogen production device provides reaction heat for the reaction chamber of the reforming hydrogen production device. The heating outer chamber of the reforming hydrogen production device is connected to the preheating box through a pipeline. The preheating box is used to preheat the ammonia-containing gas input into the reaction inner chamber of the reforming hydrogen production device through the ammonia engine exhaust gas from the heating outer chamber. The ammonia engine exhaust gas is used to provide reaction heat for the reforming hydrogen production device, and the ammonia engine exhaust gas is used for a second time to preheat the ammonia-containing gas to enter the reaction inner chamber, thereby improving the heat exchange efficiency of the hydrogen production reaction, increasing the hydrogen production amount, and thus improving the engine operation performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of an ammonia fuel combustion system provided by an embodiment of the present invention;

[0030] Figure 2 It is a structural schematic diagram of a reforming hydrogen production device provided in an embodiment of the present invention;

[0031] Figure 3 It is a partial cross-sectional view of a reforming hydrogen production device provided by an embodiment of the present invention and provided with a metal coil;

[0032] Figure 4 is a communication connection diagram of an ammonia fuel combustion system provided by an embodiment of the present invention;

[0033] Figure 5 It is a flow chart of a control method of an ammonia fuel combustion system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0034] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar components or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0035] In the description of the present invention, it should be understood that descriptions involving orientation, such as up, down, left, right, etc., the orientations or positional relationships indicated are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0036] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the sequence of the indicated technical features.

[0037] Please refer to Figure 1 An embodiment of the present invention provides an ammonia fuel combustion system, including: an ammonia engine 101, a reforming hydrogen production device 102, a preheating box 103, an ammonia storage 104, a premixer 105 and a turbocharger 106, wherein the reforming hydrogen production device includes a reaction inner chamber and a heating outer chamber.

[0038] The reaction chambers of the ammonia storage, turbocharger and reforming hydrogen production device are all connected to the premixer through pipelines, and the premixer is connected to the feed port of the ammonia engine through pipelines. The ammonia storage is used to store ammonia fuel, the turbocharger is used to transport a certain amount of external air into the premixer for premixing with ammonia, and the premixer is used to mix the gases from the reaction chambers of the ammonia storage, turbocharger and reforming hydrogen production device. Furthermore, a first plasma generator 107 is also provided at the fuel outlet of the ammonia storage, and the plasma generator can activate the ammonia gas flowing through it, which can improve the combustion characteristics of ammonia. In this embodiment, the provision of a premixer enables the fuel and air to be premixed in the intake duct of the ammonia engine without the need for premixing, and to be directly injected into the cylinder before being introduced into the engine for combustion.

[0039] The ammonia storage and the turbocharger are both connected to the reaction chamber of the reforming hydrogen production device through pipelines. The reaction chamber of the reforming hydrogen production device is used to decompose the ammonia-containing gas from the ammonia storage and the turbocharger to obtain hydrogen-containing gas, and provide the hydrogen-containing gas to the premixer. The exhaust gas outlet of the ammonia engine is connected to the heating outer chamber of the reforming hydrogen production device through a pipeline. The heating outer chamber of the reforming hydrogen production device is used to provide reaction heat for the reaction chamber of the reforming hydrogen production device. The heating outer chamber of the reforming hydrogen production device is connected to the preheating box through a pipeline. The preheating box is used to preheat the ammonia-containing gas input into the reaction chamber of the reforming hydrogen production device through the ammonia engine exhaust gas from the heating outer chamber. This embodiment uses the ammonia engine exhaust gas to provide reaction heat for the reforming hydrogen production device, and then uses the ammonia engine exhaust gas for a second time to preheat the ammonia-containing gas to enter the reaction chamber, thereby improving the heat exchange efficiency of the hydrogen production reaction, increasing the hydrogen production amount, and thus improving the engine operation performance.

[0040] According to some embodiments of the present invention, please refer to Figure 2 The reaction chamber of the reforming hydrogen production device includes a top cavity 201, a bottom cavity 202 and a plurality of pipes 203. The tops of the plurality of pipes are connected to the top cavity, and the bottoms of the plurality of pipes are connected to the bottom cavity. The plurality of pipes are arranged in the heating outer cavity 204, and the direction of the pipes is perpendicular to the flow direction of the ammonia engine exhaust gas in the heating outer cavity. Specifically, in the reforming hydrogen production device, the engine exhaust gas with residual heat passes from the inside of the horizontal shell (such as Figure 2 The gas and catalyst in the tube bundle are heated and insulated, and the ammonia-carrying gas and air (i.e., ammonia-containing gas) pass through the vertical tube bundle inlet and then flow out from the outlet (as shown by the blue arrow). The overall macroscopic flow direction of the two is reversed, and there is space for gas diffusion and turning at the top and bottom of the reaction cavity. There is a baffle at the air inlet to allow the gas to enter the tube evenly. Catalysts that promote oxidation and decomposition to produce hydrogen are deposited inside the pipeline. There is a certain distance between the tube bundles to promote turbulent flow of hot exhaust gas and enhance heat exchange. The air inlet is connected to the shell by a flange and screws, and is sealed by a sealing sheet for easy installation and disassembly. The reforming hydrogen production device proposed in this embodiment has a compact structure, a small footprint, high space and material utilization, and no baffle structure is required inside, so the initial cost is low. For the reformer, the compact structure can improve the overall hydrogen production efficiency. Compared with the shell and tube reformer with a baffle structure in the related art, the reforming hydrogen production device proposed in this embodiment has a lower flow resistance, so the heat exchange efficiency under unit back pressure is higher. At the same time, the front and back arrangement of multiple pipes makes the types of catalysts used more flexible. For example, a catalyst that promotes the decomposition of ammonia to produce hydrogen and a catalyst that promotes the oxidation and heat release of ammonia can be used at the same time to provide the required heat for the hydrogen production reaction, or a part of it can be left as an empty pipe to fully preheat it so that it reaches a more suitable reaction temperature when it makes initial contact with the catalyst.

[0041] According to some embodiments of the present invention, please refer to Figure 3 The outside of the reaction chamber of the reforming hydrogen production device is wound with a metal coil 301, which can also be understood as winding a metal coil outside the heating chamber. Specifically, a sleeve is provided on the side of the heating chamber to hold the discharge coil. Figure 3 The brownish yellow part is the cross section of the electric coil. The coil is wound in the same winding direction to ensure that the magnetic fields are formed in the same direction and do not cancel each other out. By controlling the voltage and current intensity applied to the metal coil, the frequency and intensity of the magnetic field generated by it can be controlled, and the hydrogen production efficiency of the reformer can be regulated, thereby controlling its hydrogen outlet volume to meet the intake requirements of different engine operating conditions.

[0042] According to some embodiments of the present invention, please continue to refer to Figure 1The ammonia fuel combustion system also includes a cooling and liquid removal device 108, which is arranged on the pipeline between the reaction cavity of the reforming hydrogen production device and the premixer. The cooling and liquid removal device is used to remove moisture from the hydrogen-containing gas from the reaction cavity. In the reaction cavity of the reforming hydrogen production device, first, a part of the pipeline performs an oxidation reaction on the input ammonia-containing gas to generate nitrogen and water vapor, release heat, and heat the mixed gas mainly composed of ammonia. Then it is passed into the rear part of the pipeline to perform a decomposition hydrogen production reaction to obtain a hydrogen-containing gas containing hydrogen, ammonia, nitrogen, and water vapor. The reaction cavity of the reforming hydrogen production device outputs the hydrogen-containing gas, and the moisture therein is removed by the cooling and liquid removal device, and then the hydrogen-containing gas is mixed with ammonia through the premixer.

[0043] Furthermore, a second plasma generator 109 is provided on the pipeline between the cooling and liquid removal device and the premixer. The hydrogen-containing gas is output from the reaction cavity of the reforming hydrogen production device, and the water therein is removed by the cooling and liquid removal device. Then, the gas is activated by the second plasma generator and then enters the premixer for mixing. Both the ammonia and hydrogen-rich gas entering the premixer are activated to improve their combustion characteristics, thereby improving the engine efficiency.

[0044] According to some embodiments of the present invention, please continue to refer to Figure 1 The ammonia fuel combustion system further includes an electric heater 110, which is disposed on the air inlet pipeline of the reaction chamber of the reforming hydrogen production device, and is used to heat the ammonia-containing gas input into the reaction chamber of the reforming hydrogen production device. In this embodiment, adding an electric heater to the ammonia fuel combustion system can increase the upper limit of the ammonia inlet temperature of the reforming hydrogen production device, thereby increasing the maximum hydrogen production rate.

[0045] According to some embodiments of the present invention, the ammonia fuel combustion system further includes an exhaust gas treatment device 111, and the cooling and deliquidation device and the preheating box are both connected to the exhaust gas treatment device through pipelines. The exhaust gas treatment device is used to react the ammonia water mixture remaining in the cooling and deliquidation device and the ammonia engine exhaust gas passing through the preheating box, and discharge the treated exhaust gas after the reaction. In this embodiment, the ammonia water mixture separated by the cooling and deliquidation device is passed into the exhaust gas treatment device, and the ammonia water mixture undergoes a selective catalytic reaction with the engine exhaust gas after the secondary heat exchange, and the exhaust gas treatment device then discharges the exhaust gas after the reaction.

[0046] According to some embodiments of the present invention, the ammonia storage device is connected to the exhaust gas treatment device through a pipeline, and a pollutant concentration sensor 112 is also provided on the exhaust port of the exhaust gas treatment device. The pollutant concentration sensor can be used to detect NO in the exhaust gas. X If the concentration is too high, part of the ammonia activated by the first plasma generator is introduced to eliminate the harmful NOx therein and generate nitrogen and water, which are harmless to the environment, and then discharged into the atmosphere.

[0047] According to some embodiments of the present invention, the ammonia fuel combustion system further includes a controller, see Figure 1 and Figure 4 A flow meter 02 is provided at the outlet of the ammonia storage, a flow meter 01 is provided on the pipeline between the preheating box and the turbocharger, a flow meter 03 is provided on the pipeline between the ammonia storage and the preheating box, and a flow meter 04 is provided on the pipeline between the ammonia storage and the exhaust gas treatment device. Each flow meter, the electric valve on each pipeline and the pollutant concentration sensor are connected to the controller. In addition, the controller can also be communicated with each system component in the ammonia fuel combustion system, and the controller can control the working status of the system components.

[0048] The controller can automatically control the ammonia fuel combustion system. The controller is specifically used for:

[0049] Obtain the operating power and operating time of the ammonia engine;

[0050] Determine the current operation stage of the ammonia engine based on the operating power and the operating time;

[0051] Determine the corresponding ammonia engine fuel demand and system operating mode according to the operation stage;

[0052] The corresponding system components are turned on according to the system working mode, and the working parameters of the system components are adjusted according to the fuel demand of the ammonia engine, wherein the system components include an ammonia engine, a reforming hydrogen production device, an ammonia storage, a turbocharger, a metal coil power supply device and an electric heater.

[0053] Specifically, the working modes of each system are introduced as follows:

[0054] The first system working mode: When the system is initially running, there is no high-temperature exhaust gas to heat the catalyst and ammonia. Pure ammonia is used for combustion. Ammonia flows out of the ammonia storage tank and flows through the first plasma generator. The first plasma generator activates the ammonia flowing through to improve the combustion characteristics of ammonia. The turbocharger conveys a certain amount of external air into the premixer for premixing with ammonia, and then the mixed gas in the premixer is input into the ammonia engine for combustion.

[0055] The second system working mode: when the engine power is greater than the first preset value and the second preset value, this stage is a low-load operation stage, and ammonia-hydrogen mixed combustion is adopted. In this mode, the ammonia coming out of the ammonia storage tank is activated by the first plasma generator, and then it is passed into the preheating box together with the air coming out of the turbocharger in a certain proportion. In the preheating box, the mixed gas of ammonia and air is subjected to secondary heat exchange with the engine exhaust gas that has undergone a heat exchange in the reforming hydrogen production device to achieve a preheating effect, and then the mixed gas of ammonia and air flows into the reforming hydrogen production device. In the reforming hydrogen production device, ammonia is first oxidized in part of the pipeline to generate nitrogen and water vapor, release heat, and heat the mixed gas mainly composed of ammonia; then the heated ammonia-containing gas is decomposed in the rear part of the pipeline to produce hydrogen, and a hydrogen-containing gas containing hydrogen, ammonia, nitrogen, and water vapor is obtained. The reforming hydrogen production device outputs hydrogen-containing gas, which passes through the cooling and liquid removal device to separate hydrogen, nitrogen and ammonia. The cooling and liquid removal device removes the water therein, and the hydrogen-rich gas then enters the second plasma generator for activation, and then enters the premixer for premixing with ammonia and air. The gas output from the premixer is input into the ammonia engine for combustion.

[0056] The third system working mode: when the engine power is greater than the second preset value and less than the third preset value, ammonia-hydrogen mixed combustion is adopted. The third system working mode is based on the second system working mode, and the metal coil is turned on. In the reforming hydrogen production device, the heat release of ammonia oxidation, the metal coil improves the catalyst activity and the exhaust gas heat supply are coupled, that is, the heat of reaction is provided by oxidation heat release and exhaust gas; the metal coil is energized, and electromagnetic induction improves the catalyst activity, reduces the reaction activation energy, and increases and controls the hydrogen production.

[0057] In the fourth system working mode, when the engine power is greater than the third preset value, this stage is a high-speed operation stage, using ammonia-hydrogen mixed combustion. Based on the third system working mode, the fourth system working mode starts the electric heater to a certain temperature to heat the ammonia, further improving and controlling the hydrogen production.

[0058] In some embodiments, a hydrogen concentration sensor 113 is also provided at the outlet of the reaction chamber of the reforming hydrogen production device. The hydrogen concentration sensor is connected to a controller. The controller monitors the hydrogen concentration in the hydrogen-containing gas output by the reforming hydrogen production device, so as to determine whether the hydrogen content input to the ammonia engine meets the engine operation standard, and then adjusts the hydrogen content output by the reforming hydrogen production device by adjusting the amount of current flowing into the metal coil and the power of the electric heater.

[0059] In some embodiments, please refer to Figure 4In order to meet the engine operation requirements, the controller matches the engine working conditions, transmits the speed and temperature signals to the host computer, obtains the speed n and temperature t, and the host computer transmits the signal instructions back to the controller according to the working condition requirements and engine parameters. The controller excites the drive module and then controls each flow meter. Then, through real-time sensor monitoring, the hydrogen content entering the engine and the exhaust NOx content are monitored to match the inflow of each working medium with the engine operation, and to make the exhaust gas meet the environmental protection requirements. The control logic of the controller to realize various system working modes is as follows:

[0060] When the engine speed starts running from n=0 (i.e., the initial operating power is zero) within 5 seconds, this stage is determined to be the startup stage, and pure ammonia is used for startup, corresponding to the first system working mode. In the first system working mode, the host computer matches the amount of ammonia required by the engine, sends a signal to the controller, and the controller drives the drive module to turn on the flow meter 02 and the turbocharger, controls the air flow entering the system, and controls the ammonia flow into the premixer through the electric valve of the pipeline between the ammonia storage and the premixer. It should be noted that since the flow meter 01 is not turned on, the air flow into the system is the flow into the premixer, and the plasma generator is started and regulated to activate the ammonia, match the ammonia inlet flow, and then enter the engine for combustion. The engine transmits the relevant operating data to the host computer. If the operating state is stable for 5s, the startup stage is stable and the system starts successfully.

[0061] After the startup phase, when the engine power is greater than the first preset value and less than the second preset value, this phase is a low-load operation phase, using ammonia-hydrogen mixed combustion, corresponding to the second system working mode. The host computer matches the fuel ratio required by the engine and sends a signal to the controller. The controller drives the drive module to start and adjust the flow meter 03, and at the same time adjusts the flow meter 01 and the flow meter 02, and then adjusts the corresponding engine ammonia-hydrogen fuel ratio, and at the same time drives the drive module to start and adjust the second plasma generator to match the ammonia inlet flow. Ammonia enters the reforming hydrogen production device to react, and at the same time, the hydrogen concentration sensor monitors the hydrogen concentration generated by the reforming hydrogen production device in real time. By adjusting the ammonia content input to the reforming hydrogen production device, the hydrogen content output by the reforming hydrogen production device reaches the engine operation standard. Finally, the engine operating speed, torque and other working condition related signals and the exhaust gas temperature signal are transmitted to the controller, and then transmitted to the host computer by the controller to meet the working condition requirements.

[0062] When the engine power is greater than the second preset value and less than the third preset value, ammonia-hydrogen mixed combustion is adopted, corresponding to the third system working mode. In the third system working mode, the host computer matches the fuel ratio required by the engine and sends a signal to the controller. The controller drives the drive module to adjust the flow meter 03, and at the same time adjusts the flow meters 01 and 02, thereby adjusting the corresponding engine ammonia-hydrogen fuel ratio. The drive module sends a control signal to the electric coil to make it reach a certain magnetic field strength. At the same time, the hydrogen concentration sensor monitors the hydrogen concentration generated by the reforming hydrogen production device in real time. By adjusting the ammonia content input to the reforming hydrogen production device and adjusting the amount of power supplied to the metal coil, the hydrogen content outputted by the reforming hydrogen production device reaches the engine operation standard. Finally, the engine operating speed, torque and other working condition related signals and the exhaust gas temperature signal are transmitted to the controller, and then transmitted to the host computer by the controller to ensure that the working condition requirements are met.

[0063] When the engine power is greater than the third preset value, this stage is a high-speed operation stage, using ammonia-hydrogen mixed combustion and the fourth system working mode. In the fourth system working mode, the host computer matches the fuel ratio required by the engine and sends a signal to the controller. The controller drives the drive module to start and adjust the flow meter 03, and at the same time adjusts the flow meters 01 and 02. The controller drives the drive module to send a control signal to the electric heater and the power-on device of the metal coil to control the heating temperature of the electric heater and the magnetic field strength of the metal coil, thereby adjusting the corresponding engine ammonia-hydrogen fuel ratio. At the same time, the hydrogen concentration sensor monitors the hydrogen concentration generated by the reforming hydrogen production device in real time. By adjusting the ammonia content of the input reforming hydrogen production device, the amount of metal coil power and the power of the electric heater, the hydrogen content output by the engine is adjusted to meet the engine operation standard, and the plasma generator is adjusted to activate the ammonia to match the ammonia inlet flow. Finally, the engine transmits the working condition related signals such as speed and torque and the exhaust gas temperature signal to the controller, and then the controller transmits it to the host computer to ensure that the working condition requirements are met.

[0064] According to some embodiments of the present invention, the ammonia fuel combustion system further includes a controller, wherein the controller is configured to:

[0065] Acquiring pollutant concentration values ​​through pollutant concentration sensors;

[0066] When the pollutant concentration value is greater than the concentration threshold, the valve on the pipeline between the ammonia storage device and the exhaust gas treatment device is controlled to open to introduce ammonia into the exhaust gas treatment device.

[0067] Please continue to refer to Figure 4After the engine exhaust flows through the reforming hydrogen production device, it enters the exhaust gas treatment device for selective catalytic reaction. At the same time, the pollutant concentration sensor detects the exhaust gas in real time and transmits the component concentration to the host computer. If the host computer determines that the NOx content exceeds the standard, the host computer sends an instruction to the controller, and the drive module controls the corresponding electric valve according to the instruction to pass part of the ammonia activated by the first ion generator into the exhaust gas treatment device, thereby eliminating the harmful NOx therein.

[0068] According to some embodiments of the present application, the embodiments of the present application have the following beneficial effects:

[0069] (1) A multi-stage energy utilization and waste gas treatment system is used for the waste heat of engine exhaust gas. The coupling coil magnetic field increases the catalyst activity, the electric heater increases the initial reaction temperature of the reaction gas, and the plasma generator activates all the reacting ammonia. In the reforming hydrogen production device, the ammonia oxidation exothermic reaction and the hydrogen production reaction proceed simultaneously, the hydrogen production rate is high and easy to control, and the energy utilization rate is high.

[0070] (2) Structural design of the reforming hydrogen production device. The vertical arrangement of the pipeline can make the space more compact. Different catalysts can be stacked between each section of the pipeline according to demand to meet the demand for efficient hydrogen production. The oxidation heat release of the hydrogen-carrying substance and the endothermic heat of hydrogen production are combined to provide heat for the endothermic reaction of hydrogen production. The end cover and the shell are connected by screws to facilitate disassembly and catalyst stacking, improve the arrangement and spacing of the pipelines, enhance the turbulence of the exhaust gas, and enhance the heat exchange between the two. In addition, when a certain intensity of voltage and current are passed through the metal coil around the reforming hydrogen production device, a certain magnetic field will be generated, thereby increasing the activity of the catalyst and reducing the reaction activation energy of the hydrogen production reaction, thereby further improving the hydrogen production efficiency and further controlling the hydrogen production rate.

[0071] (3) The control strategy of the control system that matches the system working mode controls the feed ratio of each material and the temperature of the electric heater by the controller, which effectively improves the energy utilization rate while meeting the complex operating conditions of the engine. In addition, the partitioned control of the energy part and the harmful gas treatment part are relatively independent and work together.

[0072] (4) The cooling and dehydration device only removes the water in the gas. Compared with the intercoolers of other related systems, the temperature of the gas flowing out of this cooling unit is relatively higher, which is more conducive to the combustion of fuel in the engine.

[0073] Please refer to Figure 5 The embodiment of the present invention further provides a control method for an ammonia fuel combustion system, which is applied to the ammonia fuel combustion system of the above embodiment, and the control method comprises the following steps:

[0074] Step S201, obtaining the operating power and operating time of the ammonia engine;

[0075] Step S202, determining the current operating stage of the ammonia engine according to the operating power and the operating time;

[0076] Step S203, determining the corresponding ammonia engine fuel demand and system operating mode according to the operating stage;

[0077] Step S204, starting corresponding system components according to the system working mode, and adjusting the working parameters of the system components according to the fuel demand of the ammonia engine, wherein the system components include an ammonia engine, a reforming hydrogen production device, an ammonia storage, a turbocharger, a metal coil power supply device and an electric heater.

[0078] It can be understood that the contents of the above system embodiments are all applicable to the present method embodiments, the functions specifically implemented by the present method embodiments are the same as those of the above system embodiments, and the beneficial effects achieved are also the same as those achieved by the above system embodiments.

[0079] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the purpose of the present invention.

Claims

1. An ammonia fuel combustion system, characterized in that: include: An ammonia engine, a reforming hydrogen production device, a preheating box, an ammonia storage device, a premixer and a turbocharger, wherein the reforming hydrogen production device comprises a reaction inner chamber and a heating outer chamber; The ammonia storage, the turbocharger and the reaction inner cavity of the reforming hydrogen production device are all connected to the premixer through pipelines, and the premixer is connected to the feed port of the ammonia engine through a pipeline. The premixer is used to mix the gases from the ammonia storage, the turbocharger and the reaction inner cavity of the reforming hydrogen production device; The ammonia storage and the turbocharger are both connected to the reaction chamber of the reforming hydrogen production device through pipelines, and the reaction chamber of the reforming hydrogen production device is used to decompose the ammonia-containing gas from the ammonia storage and the turbocharger to obtain hydrogen-containing gas, and provide the hydrogen-containing gas to the premixer; The exhaust gas outlet of the ammonia engine is connected to the heating outer chamber of the reforming hydrogen production device through a pipeline, and the heating outer chamber of the reforming hydrogen production device is used to provide reaction heat for the reaction inner chamber of the reforming hydrogen production device; The heating outer chamber of the reforming hydrogen production device is connected to the preheating box through a pipeline, and the preheating box is used to preheat the ammonia-containing gas input into the reaction inner chamber of the reforming hydrogen production device through the ammonia engine exhaust gas from the heating outer chamber.

2. The ammonia fuel combustion system according to claim 1, characterized in that: The reaction inner chamber of the reforming hydrogen production device includes a top cavity, a bottom cavity and multiple pipes, the tops of the multiple pipes are connected to the top cavity, and the bottoms of the multiple pipes are connected to the bottom cavity; the multiple pipes are arranged in the heating outer chamber, and the direction of the pipes is perpendicular to the flow direction of the ammonia engine exhaust gas in the heating outer chamber.

3. The ammonia fuel combustion system according to claim 2, characterized in that: The ammonia fuel combustion system also includes a cooling and liquid removal device, which is arranged on a pipeline between the reaction cavity of the reforming hydrogen production device and the premixer, and is used to remove moisture from the hydrogen-containing gas from the reaction cavity.

4. The ammonia fuel combustion system according to claim 3, characterized in that: A metal coil is wound around the outside of the reaction inner cavity of the reforming hydrogen production device.

5. The ammonia fuel combustion system according to claim 4, characterized in that: The ammonia fuel combustion system also includes an electric heater, which is arranged on the air inlet pipeline of the reaction chamber of the reforming hydrogen production device, and is used to heat the ammonia-containing gas input into the reaction chamber of the reforming hydrogen production device.

6. The ammonia fuel combustion system according to claim 5, characterized in that: The ammonia fuel combustion system also includes an exhaust gas treatment device, and the cooling and deliquidation device and the preheating box are both connected to the exhaust gas treatment device through pipelines. The exhaust gas treatment device is used to react the remaining ammonia water mixture in the cooling and deliquidation device and the ammonia engine exhaust gas passing through the preheating box, and discharge the treated tail gas after the reaction.

7. The ammonia fuel combustion system according to claim 6, characterized in that: The ammonia storage device is connected to the exhaust gas treatment device through a pipeline, and a pollutant concentration sensor is also arranged on the exhaust port of the exhaust gas treatment device.

8. The ammonia fuel combustion system according to claim 5, characterized in that: The ammonia fuel combustion system further includes a controller, which is used to: Obtain the operating power and operating time of the ammonia engine; determining a current operating stage of the ammonia engine according to the operating power and the operating time; determining a corresponding ammonia engine fuel requirement and a system operating mode according to the operating stage; The corresponding system components are turned on according to the system operating mode, and the operating parameters of the system components are adjusted according to the fuel demand of the ammonia engine, wherein the system components include an ammonia engine, a reforming hydrogen production device, an ammonia storage, a turbocharger, a metal coil power supply device and an electric heater.

9. The ammonia fuel combustion system according to claim 7, characterized in that: The ammonia fuel combustion system further includes a controller, which is used to: Acquiring a pollutant concentration value through the pollutant concentration sensor; When the pollutant concentration value is greater than the concentration threshold, the valve on the pipeline between the ammonia storage device and the exhaust gas treatment device is controlled to open so as to introduce ammonia gas into the exhaust gas treatment device.

10. A control method for an ammonia fuel combustion system, characterized in that: Applied to the ammonia fuel combustion system as claimed in claim 5, the control method comprises the following steps: Obtain the operating power and operating time of the ammonia engine; determining a current operating stage of the ammonia engine according to the operating power and the operating time; determining a corresponding ammonia engine fuel requirement and a system operating mode according to the operating stage; The corresponding system components are turned on according to the system operating mode, and the operating parameters of the system components are adjusted according to the fuel demand of the ammonia engine, wherein the system components include an ammonia engine, a reforming hydrogen production device, an ammonia storage, a turbocharger, a metal coil power supply device and an electric heater.

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