Ammonia-hydrogen fusion engine system and control method thereof

Abstract

The invention belongs to the technical field of clean energy, and particularly relates to an ammonia-hydrogen fusion engine system and a control method thereof.The ammonia-hydrogen fusion engine system comprises an engine, a liquid ammonia vaporization device, an ammonia reaction hydrogen production device, a hydrogen-nitrogen mixer and an overheating protection device; the overheating protection device comprises a bypass branch which is arranged in parallel with the ammonia reaction hydrogen production device, one end of the bypass branch is communicated with the upstream of the second pipeline, and the other end of the bypass branch is communicated with the downstream of the second pipeline; the bypass valve is arranged on the bypass branch; the first sensor is arranged on the upstream of the second pipeline and used for sensing the first temperature of the tail gas, and the second sensor is arranged on the ammonia reaction hydrogen production device and used for sensing the second temperature of the catalyst; the controller is used for adjusting the opening degree of the bypass valve according to the relation among the first temperature, the second temperature and a target temperature threshold value. The ammonia hydrogen production conversion rate and the tail gas heat utilization rate can be increased, and overheating protection can be provided for an ammonia reaction hydrogen production device.

Description

Technical Field

[0001] The present application relates to the field of clean energy technology, and more specifically, to an ammonia-hydrogen fusion engine system and a control method thereof. Background Art

[0002] With the development of industry, people pay more and more attention to environmental protection, and the use and research of various clean energy sources have gradually been carried out. Among them, hydrogen energy is widely used as an efficient and environmentally friendly green energy. However, the storage and transportation of hydrogen energy and the cost of the supply chain have always been one of the troublesome factors in the development of hydrogen energy. Ammonia is a bulk inorganic compound that is easy to transport and store after liquefaction, and ammonia is a carbon-free, hydrogen-rich energy carrier. Therefore, the ammonia-hydrogen fusion engine system produces hydrogen as fuel by decomposing ammonia, which has become a technical solution with good economic benefits and sustainable development.

[0003] The ammonia reaction hydrogen production device is one of the important components of the ammonia-hydrogen fusion engine system. The internal working process of the ammonia reaction hydrogen production device is an endothermic expansion reaction, which makes it have very high requirements for temperature. Under actual working conditions, the ammonia reaction hydrogen production device needs to be controlled within a certain temperature range. When the temperature is lower than the target temperature, the conversion efficiency of ammonia to hydrogen is low, which will affect the overall combustion performance of the ammonia-hydrogen fusion engine system. When the temperature is higher than the operating temperature, the catalyst activity in the ammonia reaction hydrogen production device will decrease, causing irreversible damage. Most of the existing ammonia hydrogen production reaction devices use external electric heaters as heat sources, and this method consumes a lot of electricity. At the same time, the exhaust waste heat discharge of the ammonia-hydrogen fusion engine system will take away part of the energy, reducing the efficiency of the ammonia-hydrogen fusion engine system. Summary of the invention

[0004] The purpose of the present application is to provide an ammonia-hydrogen fusion engine system and a control method thereof, which can not only improve the conversion rate of ammonia to hydrogen and the utilization rate of exhaust gas heat, but also provide overheating protection for the ammonia reaction hydrogen production device, ensuring that the ammonia reaction hydrogen production device operates within safe and effective boundary conditions.

[0005] In a first aspect, an embodiment of the present application provides an ammonia-hydrogen fusion engine system, including an engine, a liquid ammonia vaporization device, an ammonia reaction hydrogen production device, a hydrogen-nitrogen mixer, and an overheating protection device. The engine has an intake manifold and an exhaust manifold. The intake manifold is connected to the hydrogen-nitrogen mixer through a first pipeline, and the exhaust manifold discharges exhaust gas through a second pipeline. The second pipeline runs through the ammonia reaction hydrogen production device. The interior of the ammonia reaction hydrogen production device is filled with a catalyst. The ammonia reaction hydrogen production device has an inlet end and an outlet end. The inlet end is connected to the liquid ammonia vaporization device through a third pipeline. The liquid ammonia vaporization device is used to vaporize liquid ammonia into ammonia gas. The outlet end is connected to the hydrogen-nitrogen mixer through a fourth pipeline. The overheat protection device comprises: a bypass branch, which is arranged in parallel with the ammonia reaction hydrogen production device, one end of the bypass branch is connected to the upstream of the second pipeline, and the other end is connected to the downstream of the second pipeline; a bypass valve, which is arranged on the bypass branch; a first sensor and a second sensor, the first sensor is arranged on the upstream of the second pipeline, and is used to sense a first temperature of the exhaust gas, and the second sensor is arranged on the ammonia reaction hydrogen production device, and is used to sense a second temperature of the catalyst; and a controller, which is electrically connected to the first sensor, the second sensor and the bypass valve, and is used to adjust the opening of the bypass valve according to the relationship between the first temperature, the second temperature and the target temperature threshold.

[0006] In addition, the ammonia-hydrogen fusion engine according to the present application may also have the following additional technical features:

[0007] In some embodiments of the present application, the overheat protection device further includes a heat exchanger, which is disposed on the bypass branch and upstream of the bypass valve, and is used for performing heat exchange with the exhaust gas entering the bypass branch.

[0008] In some embodiments of the present application, the ammonia-hydrogen fusion engine system also includes a liquid supply device, which includes an inlet pipe and an outlet pipe that are interconnected. The heat exchanger has an inlet and an outlet, and the inlet pipe is connected to the inlet, and the outlet pipe is connected to the outlet.

[0009] In some embodiments of the present application, the ammonia-hydrogen fusion engine system also includes a post-processing device, the ammonia reaction hydrogen production device includes a hydrogen production chamber for accommodating ammonia and a catalyst, the inlet end and the outlet end are arranged in the hydrogen production chamber, and the second pipeline passes through the hydrogen production chamber and is connected to the post-processing device.

[0010] In some embodiments of the present application, a pressure sensor is also provided on the ammonia reaction hydrogen production device, and a pressure regulating valve, a first buffer device and an ammonia injection valve are sequentially provided on the third pipeline along the direction from the liquid ammonia vaporization device to the inlet end of the ammonia reaction hydrogen production device, and the pressure regulating valve is used to adjust the pressure of the mixed gas containing hydrogen and nitrogen; along the direction from the outlet end of the ammonia reaction hydrogen production device to the hydrogen-nitrogen mixer, a first filter, a second buffer device and a hydrogen-nitrogen injection valve are sequentially provided on the fourth pipeline.

[0011] In some embodiments of the present application, the turbine of the engine is connected to the exhaust manifold, and the turbine is coaxially connected to the compressor to drive the compressor to increase the pressure of the air and hydrogen-nitrogen mixture; the hydrogen-nitrogen mixer is connected to the air inlet end of the compressor, and the air outlet end of the compressor is connected to the intake manifold through a first pipeline. An intercooler and a throttle are also provided on the first pipeline. The intercooler is used to cool the air, hydrogen, nitrogen and ammonia mixture compressed by the compressor.

[0012] In some embodiments of the present application, the hydrogen-nitrogen mixer is also connected to an air intake pipe, and the air intake pipe is also provided with a second filter for purifying the air.

[0013] In some embodiments of the present application, the liquid ammonia vaporization device includes a liquid ammonia tank, a liquid ammonia pump and a liquid ammonia vaporizer. The liquid ammonia tank is connected to the liquid ammonia vaporizer through the liquid ammonia pump. The cooling water of the engine is connected to the liquid ammonia vaporizer through the fifth pipeline for heat exchange with the liquid ammonia in the liquid ammonia vaporizer. A control valve is provided on the fifth pipeline.

[0014] In the second aspect, an embodiment of the present application provides a control method for an ammonia-hydrogen fusion engine system, which is applied to the ammonia-hydrogen fusion engine system of each embodiment of the present application, and the control method includes: obtaining a first temperature of the exhaust gas sensed by a first sensor and a second temperature of the catalyst sensed by a second sensor; and adjusting the opening of the bypass valve according to the relationship between the first temperature, the second temperature and the target temperature threshold.

[0015] In some embodiments of the present application, adjusting the opening of the bypass valve according to the relationship between the first temperature, the second temperature and the target temperature threshold includes: controlling the bypass valve to close according to the first temperature being lower than the first temperature threshold and the second temperature being lower than the second temperature threshold; controlling the bypass valve to open according to the first temperature being higher than the first temperature threshold and the second temperature being higher than the second temperature threshold, and the opening of the bypass valve changes linearly with the second temperature.

[0016] According to the ammonia-hydrogen fusion engine and control method thereof provided in the embodiment of the present application, an overheating protection device is provided in parallel with the ammonia reaction hydrogen production device, the overheating protection device includes a bypass branch, a bypass valve and a controller provided on the bypass branch, and a first sensor for sensing a first temperature of the exhaust gas discharged by the engine and a second sensor for sensing a second temperature of the catalyst. The controller adjusts the opening of the bypass valve according to the relationship between the first temperature, the second temperature and the target temperature threshold, so that the exhaust gas discharged by the engine can be used to improve the conversion rate of ammonia to hydrogen and the exhaust gas heat utilization rate, and overheating protection can be provided for the ammonia reaction hydrogen production device by controlling the opening of the bypass valve, thereby ensuring that the ammonia reaction hydrogen production device operates within safe and effective boundary conditions.

[0017] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. In addition, the same reference numerals are used throughout the accompanying drawings to represent the same components. Among them:

[0019] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. In addition, the same reference numerals are used throughout the accompanying drawings to represent the same components. Among them:

[0020] Figure 1 This is a schematic structural diagram of an ammonia-hydrogen fusion engine system according to an embodiment of the present application;

[0021] Figure 2 This is a schematic diagram of the structure of the overheat protection device of an embodiment of the present application;

[0022] Figure 3 This is a flowchart of a control method for an ammonia-hydrogen fusion engine system according to an embodiment of the present application.

[0023] The reference numerals in the accompanying drawings represent the following:

[0024] 100. Ammonia-hydrogen fusion engine system;

[0025] 10. Overheat protection device; 20. Engine; 21. Intake manifold; 22. Exhaust manifold; 23. Turbine; 24. Control valve;

[0026] 30. Liquid ammonia vaporization device; 31. Liquid ammonia tank; 32. Liquid ammonia pump; 33. Liquid ammonia vaporizer; 34. Pressure regulating valve; 35. First buffer device; 36. Ammonia injection valve;

[0027] 40. Ammonia reaction hydrogen production device; 41. Inlet end; 42. Outlet end;

[0028] 50. Hydrogen-nitrogen mixer; 51. First filter; 52. Second buffer device; 53. Hydrogen-nitrogen injection valve; 54. Compressor; 55. Intercooler; 56. Throttle;

[0029] 60. air intake pipe; 61. second filter; 70. post-processing device;

[0030] 1. Bypass branch; 2. Heat exchanger; 2a. Liquid inlet; 2b. Liquid outlet; 3. Bypass valve; 4. First sensor; 5. Second sensor; 6. Controller;

[0031] a, first pipeline; b, second pipeline; c, third pipeline; d, fourth pipeline; f, fifth pipeline. DETAILED DESCRIPTION

[0032] The exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0033] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0034] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0035] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both upper and lower orientations. The device can be oriented otherwise (rotated 90 degrees or in other directions) and the spatial relative descriptors used in the text are interpreted accordingly.

[0036] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0037] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0038] Figure 1 This is a schematic diagram of the structure of the ammonia-hydrogen fusion engine system according to an embodiment of the present application. Figure 2 Schematic diagram of the structure of the overheat protection device of the embodiment of the present application.

[0039] See also Figure 1 and Figure 2 The embodiment of the present application provides an ammonia-hydrogen fusion engine system 100 , including an engine 20 , a liquid ammonia vaporization device 30 , an ammonia reaction hydrogen production device 40 , a hydrogen-nitrogen mixer 50 and an overheating protection device 10 .

[0040] The engine 20 has an intake manifold 21 and an exhaust manifold 22. The intake manifold 21 is connected to the hydrogen-nitrogen mixer 50 through a first pipeline a. The exhaust manifold 22 discharges exhaust gas through a second pipeline b. The second pipeline b runs through an ammonia reaction hydrogen production device 40. The interior of the ammonia reaction hydrogen production device 40 is filled with a catalyst. The ammonia reaction hydrogen production device 40 has an inlet end 41 and an outlet end 42. The inlet end 41 is connected to the liquid ammonia vaporization device 30 through a third pipeline c. The liquid ammonia vaporization device 30 is used to vaporize liquid ammonia into ammonia gas. The outlet end 42 is connected to the hydrogen-nitrogen mixer 50 through a fourth pipeline d.

[0041] The overheat protection device 10 includes a bypass branch 1 , a bypass valve 3 , a first sensor 4 , a second sensor 5 and a controller 6 .

[0042] The bypass branch 1 is arranged in parallel with the ammonia reaction hydrogen production device 40, one end of the bypass branch 1 is connected to the upstream of the second pipeline b, and the other end is connected to the downstream of the second pipeline b, and the bypass valve 3 is arranged on the bypass branch 1. The first sensor 4 is arranged upstream of the second pipeline b, and is used to sense the first temperature of the tail gas. The second sensor 5 is arranged on the ammonia reaction hydrogen production device 40, and is used to sense the second temperature of the catalyst. The controller 6 is electrically connected to the first sensor 4, the second sensor 5 and the bypass valve 3, and is used to adjust the opening of the bypass valve 3 according to the relationship between the first temperature, the second temperature and the target temperature threshold.

[0043] In this embodiment, the liquid ammonia vaporization device 30 is used to vaporize liquid ammonia into ammonia gas, and the ammonia gas is supplied to the inlet end 41 of the ammonia reaction hydrogen production device 40 through the third pipeline c. The interior of the ammonia reaction hydrogen production device 40 is filled with a catalyst, such as a ruthenium-based catalyst, and ammonia gas can be decomposed faster and more completely to generate hydrogen and nitrogen under the action of the catalyst. An endothermic expansion reaction occurs inside the ammonia reaction hydrogen production device 40, which makes it have very high requirements for temperature. For example, when the temperature of the catalyst reaches 550°C, the efficiency of ammonia hydrogen production can reach more than 99%. Under actual working conditions, the ammonia reaction hydrogen production device 40 needs to be controlled within a certain temperature range. When the temperature is lower than the target temperature, the conversion efficiency of ammonia hydrogen production is low, which will affect the overall combustion performance of the ammonia hydrogen fusion engine system 100; when the temperature is higher than the working temperature, the activity of the catalyst in the ammonia reaction hydrogen production device 40 will decrease, causing irreversible damage.

[0044] To this end, the present embodiment makes full use of the heat of the exhaust gas discharged from the exhaust manifold 22 of the engine 20 to heat the ammonia reaction hydrogen production device 40. Even when the engine 20 is cold started, the catalyst in the ammonia reaction hydrogen production device 40 can reach the required temperature. Specifically, the exhaust manifold 22 of the engine 20 discharges the exhaust gas through the second pipeline b, and the second pipeline b runs through the ammonia reaction hydrogen production device 40. The heat of the exhaust gas in the second pipeline b is used to heat the catalyst in the ammonia reaction hydrogen production device 40, so that ammonia can be decomposed to generate hydrogen and nitrogen faster, and the decomposition efficiency of ammonia and the content of hydrogen in the mixed gas are improved, thereby improving the ammonia hydrogen production conversion rate and the exhaust gas heat utilization rate. Compared with the related art of heating the ammonia reaction hydrogen production device 40 by an additional electric heater or other heat source, the present embodiment of the application can reduce power consumption and reduce production costs.

[0045] Since the temperature of the exhaust gas discharged from the exhaust manifold 22 of the engine 20 is as high as 500°C or above, for the ammonia decomposition catalyst with an operating temperature below 500°C, the operating temperature of the catalyst needs to be particularly controlled. In order to prevent the ammonia reaction hydrogen production device 40 from being damaged due to excessive temperature, the embodiment of the present application also provides an overheating protection device 10, which includes a bypass branch 1, a bypass valve 3, a first sensor 4, a second sensor 5 and a controller 6. The bypass branch 1 is arranged in parallel with the ammonia reaction hydrogen production device 40, one end of the bypass branch 1 is connected to the upstream of the second pipeline b, and the other end is connected to the downstream of the second pipeline b, so that the bypass branch 1 can take away a part of the exhaust gas discharged by the engine 20, so as to avoid the exhaust gas being completely discharged into the ammonia reaction hydrogen production device 40, resulting in damage due to excessive temperature, and the bypass valve 3 is arranged on the bypass branch 1. At the same time, a first sensor 4 is provided upstream of the second pipeline b for sensing the first temperature of the exhaust gas, and a second sensor 5 is provided on the ammonia reaction hydrogen production device 40 for sensing the second temperature of the catalyst, which can be controlled within a certain range, such as 290° C. to 300° C. The controller 6 controls the opening of the bypass valve 3 by real-time monitoring the first temperature of the exhaust gas of the engine 20 and the second temperature of the catalyst in the ammonia reaction hydrogen production device 40, thereby adjusting the proportion of the exhaust gas introduced into the ammonia reaction hydrogen production device 40, achieving precise temperature control, and having a simple control logic and a fast control response time.

[0046] Specifically, if Figure 2In the direction indicated by the middle arrow, when the first temperature T1 of the exhaust gas is lower than the first temperature threshold, the first temperature threshold may be, for example, 700°C, and the second temperature T2 of the catalyst is lower than the second temperature threshold, the second temperature threshold may be, for example, 600°C, the bypass valve 3 remains closed, and the exhaust gas discharged by the engine 20 is all discharged to the downstream of the second pipeline b through the ammonia reaction hydrogen production device 40. At this time, the exhaust gas is used as a heat source to heat the ammonia reaction hydrogen production device 40, making full use of the exhaust gas energy of the engine 20, heating the ammonia reaction hydrogen production device 40, and ensuring that the ammonia reaction hydrogen production device 40 operates in a high efficiency conversion rate range; when the first temperature T1 of the exhaust gas is higher than the first temperature threshold, and the second temperature T2 of the catalyst is higher than the second temperature threshold, the controller 6 starts to work, controls the bypass valve 3 to open, and the opening of the bypass valve 3 changes linearly with the second temperature T2. That is, the higher the second temperature T2 is within a certain range, the greater the opening of the bypass valve 3. When the second temperature T2 of the catalyst reaches the protection temperature threshold, the protection temperature threshold may be, for example, 650°C, and the bypass valve 3 is fully opened. According to the opening degree of the bypass valve 3, different proportions of the tail gas are controlled to be discharged to the downstream of the ammonia reaction hydrogen production device 40 through the bypass branch 1. At this time, the tail gas energy of the engine 20 can be fully utilized to improve the conversion efficiency of the ammonia reaction hydrogen production device 40, and at the same time, the overheating protection of the ammonia reaction hydrogen production device 40 is considered to avoid the ammonia reaction hydrogen production device 40 from being damaged due to excessive temperature, and ensure that the ammonia reaction hydrogen production device 40 works within safe and effective boundary conditions.

[0047] It is understandable that the first temperature threshold and the second temperature threshold may also be other temperature values ​​respectively, depending on the specific application scenario, which will not be elaborated herein.

[0048] According to the ammonia-hydrogen fusion engine system 100 provided in the embodiment of the present application, an overheating protection device 10 is provided in parallel with the ammonia reaction hydrogen production device 40. The overheating protection device 10 includes a bypass branch 1, a bypass valve 3 and a controller 6 provided on the bypass branch 1, and a first sensor 4 for sensing a first temperature of the exhaust gas discharged by the engine 20 and a second sensor 5 for sensing a second temperature of the catalyst. The controller 6 adjusts the opening of the bypass valve 3 according to the relationship between the first temperature, the second temperature and the target temperature threshold, so that the exhaust gas discharged by the engine 20 can be used to improve the conversion rate of ammonia to hydrogen and the exhaust gas heat utilization rate, and the ammonia reaction hydrogen production device 40 can be protected from overheating by controlling the opening of the bypass valve 3, thereby ensuring that the ammonia reaction hydrogen production device operates within safe and effective boundary conditions.

[0049] In some embodiments, the overheat protection device 10 further includes a heat exchanger 2 , which is disposed on the bypass branch 1 and upstream of the bypass valve 3 , and is used for performing heat exchange with the exhaust gas entering the bypass branch 1 .

[0050] like Figure 2As shown, the heat exchanger 2 is arranged on the bypass branch 1 and located upstream of the bypass valve 3, and is used to perform heat exchange with the exhaust gas entering the bypass branch 1 to cool the high-temperature exhaust gas. The cooled exhaust gas can protect the bypass valve 3 from being damaged due to excessive temperature, thereby improving the reliability of the overheating protection device 10. The heat exchanger 2 can be an air heat exchange device or a coolant heat exchange device.

[0051] In some embodiments, the ammonia-hydrogen fusion engine system 100 also includes a liquid supply device, which includes a liquid inlet pipe and a liquid outlet pipe that are interconnected. The heat exchanger 2 has a liquid inlet 2a and a liquid outlet 2b. The liquid inlet pipe is connected to the liquid inlet 2a, and the liquid outlet pipe is connected to the liquid outlet 2b.

[0052] like Figure 2 As shown, the heat exchanger 2 is a coolant heat exchange device, which has a liquid inlet 2a and a liquid outlet 2b, and the liquid supply device includes a liquid inlet pipe and a liquid outlet pipe that are connected to each other, the liquid inlet pipe is connected to the liquid inlet 2a, and the liquid outlet pipe is connected to the liquid outlet 2b. The heat exchanger 2 exchanges heat with the exhaust gas entering the bypass branch 1 through the coolant, and the coolant can be water, oil, etc., to cool the high-temperature exhaust gas.

[0053] In some embodiments, the ammonia-hydrogen fusion engine system 100 also includes a post-processing device 70, the ammonia reaction hydrogen production device 40 includes a hydrogen production chamber for accommodating ammonia and a catalyst, the inlet end 41 and the outlet end 42 are arranged in the hydrogen production chamber, and the second pipeline b passes through the hydrogen production chamber and is connected to the post-processing device 70.

[0054] like Figure 1 As shown, in the process of catalytic decomposition reaction, in order to make full use of the heat energy of the combustion exhaust gas of the engine 20 and reduce the impact of the nitrogen oxides and unburned ammonia products in the gas discharged from the engine 20 on the environment, the exhaust manifold 22 of the engine 20 is connected to the post-processing device 70 after passing through the hydrogen production chamber through the second pipeline b, and the exhaust heat is transferred to the hydrogen production chamber through the second pipeline b, increasing the temperature of the catalyst in the hydrogen production chamber and improving the ammonia hydrogen conversion rate. The post-processing device 7 can process nitrogen oxides and unburned ammonia products in the tail body discharged from the engine 20, so that the exhaust gas of the engine 20 meets the emission standards.

[0055] In some embodiments, a pressure sensor is also provided on the ammonia reaction hydrogen production device 40. Along the direction from the liquid ammonia vaporization device 30 to the inlet end 41 of the ammonia reaction hydrogen production device 40, a pressure regulating valve 34, a first buffer device 35 and an ammonia injection valve 36 are sequentially provided on the third pipeline, and the pressure regulating valve 34 is used to adjust the pressure of the mixed gas containing hydrogen and nitrogen; along the direction from the outlet end 42 of the ammonia reaction hydrogen production device 40 to the hydrogen-nitrogen mixer 50, a first filter 51, a second buffer device 52 and a hydrogen-nitrogen injection valve 53 are sequentially provided on the fourth pipeline d.

[0056] like Figure 1 As shown, the ammonia reaction hydrogen production device 40 is also provided with a pressure sensor (not shown in the figure). Along the flow direction of ammonia in the third pipeline c, a pressure regulating valve 34, a first buffer device 35 and an ammonia injection valve 36 are sequentially provided on the third pipeline c. The pressure regulating valve 34 is used to control the pressure of the mixed gas containing hydrogen and nitrogen, for example, the pressure is less than 50 kPa. After the buffering effect of the first buffer device 35, the vaporized ammonia is sprayed into the ammonia reaction hydrogen production device 40 through the ammonia injection valve 36. The ammonia injection valve 36 is used to control the amount of ammonia sprayed into the ammonia reaction hydrogen production device 40.

[0057] The pressure sensor is used to monitor the pressure inside the ammonia reaction hydrogen production device 40 during the ammonia decomposition process, and to control the pressure of the vaporized ammonia through the pressure regulating valve 34. The pressure of the vaporized ammonia can be controlled within a certain range, such as 3 Bar to 5 Bar. The ammonia reaction hydrogen production device 40 is monitored by the second sensor 5 and the pressure sensor, and the temperature and pressure inside the ammonia reaction hydrogen production device 40 are adjusted accordingly according to the temperature and pressure detected by the second sensor 5 and the pressure sensor, thereby controlling the conversion efficiency of the ammonia reaction hydrogen production device 40. The pressure and control temperature ranges vary according to different types of catalysts. For example, for a certain catalyst at low pressure (1 bar (gauge pressure)) and temperature 300°C, its conversion efficiency can reach 20% to control the proportion of hydrogen in the mixed gas. Optionally, the conversion efficiency of the ammonia reaction hydrogen production device 40 is controlled within the range of 10% to 20%; the pressure of the mixed gas containing hydrogen, nitrogen and ammonia discharged from the ammonia reaction hydrogen production device 40 is controlled by controlling the inlet pressure of the catalyst; wherein the pressure of the mixed gas containing hydrogen, nitrogen and ammonia discharged from the ammonia reaction hydrogen production device 40 is less than a certain pressure, such as 50 kPa.

[0058] Furthermore, along the flow direction of hydrogen and nitrogen in the fourth pipeline d, a first filter 51, a second buffer device 52 and a hydrogen-nitrogen injection valve 53 are sequentially arranged on the fourth pipeline d. The ammonia reaction hydrogen production device 40 is used to convert the input ammonia into a mixed gas containing hydrogen and nitrogen. The first filter 51 is used to filter impurities in the mixed gas. After the buffering effect of the second buffer device 52, the converted mixed gas containing hydrogen and nitrogen is sprayed into the hydrogen-nitrogen mixer 50 through the hydrogen-nitrogen injection valve 53.

[0059] In some embodiments, the hydrogen-nitrogen mixer 50 is further connected to an air intake pipe 60 , and the air intake pipe 60 is further provided with a second filter 61 for purifying the air.

[0060] like Figure 1As shown, the hydrogen-nitrogen injection valve 53 is used to spray a mixed gas of hydrogen-nitrogen and a trace amount of undecomposed ammonia into the hydrogen-nitrogen mixer 50. The hydrogen-nitrogen mixer 50 is also connected to an air intake pipe 60. The air intake pipe 60 is also provided with a second filter 61. The second filter 61 is used to purify the air. The filtered air is input into the hydrogen-nitrogen mixer 50.

[0061] In some embodiments, the turbine 23 of the engine 20 is connected to the exhaust manifold 22, and the turbine 23 is coaxially connected to the compressor 54; the hydrogen-nitrogen mixer 50 is connected to the air inlet end of the compressor 54, and the air outlet end of the compressor 54 is connected to the air inlet manifold 21 through the first pipeline a. The first pipeline a is also provided with an intercooler 55 and a throttle 56. The intercooler 55 is used to cool the mixed gas of air, hydrogen, nitrogen and ammonia compressed by the compressor 54.

[0062] like Figure 1 As shown, in order to better utilize the high-temperature exhaust energy of the engine 20, in the embodiment of the present application, the exhaust manifold 22 of the engine 20 is connected to the turbine 23, the turbine 23 is coaxially connected to the compressor 54, the hydrogen-nitrogen mixer 50 is connected to the compressor 54, and the turbine 23 can drive the compressor 54 to rotate to increase the pressure of the air and hydrogen-nitrogen mixed gas. After the compressor 54 sucks the pressurized air and the mixed gas of hydrogen, nitrogen, and ammonia into the intake manifold 21, a flammable mixed gas of hydrogen, nitrogen, ammonia, and air can be formed in the intake manifold 21 on the engine 20, wherein hydrogen accounts for 10% to 20% of the mixed gas. In addition, an intercooler 55 is provided between the intake manifold 21 and the compressor 23, and a throttle 56 is provided between the intercooler 55 and the intake manifold 21, and the intercooler 55 is used to cool the mixed gas of air, hydrogen, and nitrogen compressed by the compressor 54. The cooled mixed gas enters the cylinder of the engine 20, and the spark plug near the compression top dead center of the engine 20 ignites the mixed gas in the cylinder, converting the combustion chemical energy of the fuel into the mechanical energy of the engine, providing power for the engine 20. The engine 20 here includes necessary engine components such as a camshaft, intake and exhaust valves, a crankshaft, and a piston connecting rod; the exhaust gas after the combustion of the mixed gas is discharged through the exhaust manifold 22 on the engine 20, and then enters the post-processing device 70.

[0063] In some embodiments, the liquid ammonia vaporization device 30 includes a liquid ammonia tank 31, a liquid ammonia pump 32 and a liquid ammonia vaporizer 33. The liquid ammonia tank 31 is connected to the liquid ammonia vaporizer 33 through the liquid ammonia pump 32. The cooling water of the engine 20 is connected to the liquid ammonia vaporizer 33 through the fifth pipeline f for heat exchange with the liquid ammonia in the liquid ammonia vaporizer 33. A control valve 24 is provided on the fifth pipeline f.

[0064] like Figure 1As shown, the liquid ammonia tank 31 is connected to the liquid ammonia vaporizer 33 through the liquid ammonia pump 32 to convert liquid ammonia into gaseous ammonia. When the engine 20 is running stably, the temperature of the cooling water discharged by the engine 20 can reach above 90°C. In order to further utilize the cooling water of the engine 20 and improve the energy recycling rate of the system, as an optional embodiment of the present application, the cooling water of the engine 20 is connected to the liquid ammonia vaporizer 33 through the fifth pipeline f, which is used to exchange heat with the liquid ammonia in the liquid ammonia vaporizer 33. The cooling water of the engine 20 flows through the liquid ammonia vaporizer 33 to vaporize the liquid ammonia. A control valve 24 is provided between the engine 20 and the liquid ammonia vaporizer 33, and the control valve 24 can be opened or closed as needed.

[0065] Figure 3 This is a flowchart of a control method for an ammonia-hydrogen fusion engine system according to an embodiment of the present application.

[0066] See also Figure 3 The embodiment of the present application also provides a control method of an ammonia-hydrogen fusion engine system, which is applied to the ammonia-hydrogen fusion engine system 100 as described above. The control method includes:

[0067] Step S1: acquiring a first temperature of the exhaust gas sensed by the first sensor 4 and a second temperature of the catalyst sensed by the second sensor 5;

[0068] Step S2: adjusting the opening of the bypass valve 3 according to the relationship between the first temperature, the second temperature and the target temperature threshold.

[0069] Combination Figure 1 and Figure 2 , since the exhaust gas temperature discharged from the exhaust manifold 22 of the engine 20 is as high as 500°C or above, for the ammonia decomposition catalyst with an operating temperature below 500°C, the operating temperature of the catalyst needs to be particularly controlled. In order to prevent the ammonia reaction hydrogen production device 40 from being damaged due to excessive temperature, the ammonia hydrogen fusion engine system 100 is also provided with an overheating protection device 10, which includes a bypass branch 1, a bypass valve 3, a first sensor 4, a second sensor 5 and a controller 6. The bypass branch 1 is arranged in parallel with the ammonia reaction hydrogen production device 40, one end of the bypass branch 1 is connected to the upstream of the second pipeline b, and the other end is connected to the downstream of the second pipeline b, so that the bypass branch 1 can take away a part of the exhaust gas discharged by the engine 20, so as to avoid that the exhaust gas is completely discharged to the ammonia reaction hydrogen production device 40, which is damaged due to excessive temperature, and the bypass valve 3 is arranged on the bypass branch 1. At the same time, a first sensor 4 is arranged upstream of the second pipeline b for sensing the first temperature of the exhaust gas, and a second sensor 5 is arranged on the ammonia reaction hydrogen production device 40 for sensing the second temperature of the catalyst. The second temperature can be controlled within a certain range, for example, 290°C to 300°C.

[0070] Therefore, the control method of the ammonia-hydrogen fusion engine system is to control the opening of the bypass valve 3 by real-time monitoring the first temperature of the exhaust gas of the engine 20 and the second temperature of the catalyst in the ammonia reaction hydrogen production device 40, so as to adjust the proportion of the exhaust gas entering the ammonia reaction hydrogen production device 40, realize precise temperature control, and the control logic is simplified and the control response time is fast.

[0071] In some embodiments, in step S2, adjusting the opening of the bypass valve 3 according to the relationship between the first temperature, the second temperature and the target temperature threshold comprises:

[0072] Step S21: According to the first temperature T1 being lower than the first temperature threshold and the second temperature T2 being lower than the second temperature threshold, controlling the bypass valve 3 to close;

[0073] Step S22: According to the first temperature T1 being higher than the first temperature threshold and the second temperature T2 being higher than the second temperature threshold, the bypass valve 3 is controlled to be opened, and the opening degree of the bypass valve 3 varies linearly with the second temperature T2.

[0074] In this embodiment, the target temperature threshold includes a first temperature threshold and a second temperature threshold. The first temperature threshold may be, for example, 700°C, and the second temperature threshold may be, for example, 600°C. The first temperature threshold and the second temperature threshold may also be other temperature values, respectively, depending on the specific application scenario. When the first temperature T1 of the exhaust gas is lower than the first temperature threshold, and the second temperature T2 of the catalyst is lower than the second temperature threshold, the bypass valve 3 remains closed, and the exhaust gas discharged by the engine 20 is all discharged to the downstream of the second pipeline b through the ammonia reaction hydrogen production device 40. At this time, the exhaust gas is used as a heat source to heat the ammonia reaction hydrogen production device 40, making full use of the exhaust gas energy of the engine 20, heating the ammonia reaction hydrogen production device 40, and ensuring that the ammonia reaction hydrogen production device 40 operates in a high efficiency conversion rate range; when the first temperature T1 of the exhaust gas is higher than the first temperature threshold, and the second temperature T2 of the catalyst is higher than the second temperature threshold, the controller 6 starts to work, controls the bypass valve 3 to open, and the opening of the bypass valve 3 changes linearly with the second temperature T2. That is, the higher the second temperature T2 is within a certain range, the greater the opening of the bypass valve 3. When the second temperature T2 of the catalyst reaches the protection temperature threshold, the protection temperature threshold may be, for example, 650°C, and the bypass valve 3 is fully opened. According to the opening of the bypass valve 3, different proportions of the tail gas are controlled to be discharged to the downstream of the ammonia reaction hydrogen production device 40 through the bypass branch 1. Thus, the tail gas discharged by the engine 20 can be used to improve the conversion rate of ammonia hydrogen production and the utilization rate of tail gas heat, and the ammonia reaction hydrogen production device 40 can be protected from overheating by controlling the opening of the bypass valve 3, ensuring that the ammonia reaction hydrogen production device operates within safe and effective boundary conditions.

[0075] According to the control method of the ammonia-hydrogen fusion engine provided in the embodiment of the present application, an overheating protection device 10 is arranged in parallel with the ammonia reaction hydrogen production device 40, and the overheating protection device 10 includes a bypass branch 1, a heat exchanger 2 arranged on the bypass branch 1, a bypass valve 3 and a controller 6 located downstream of the heat exchanger 2, and a first sensor 4 for sensing a first temperature of the exhaust gas discharged by the engine 20 and a second sensor 5 for sensing a second temperature of the catalyst. The controller 6 adjusts the opening of the bypass valve 3 according to the relationship between the first temperature, the second temperature and the target temperature threshold, so that the exhaust gas discharged by the engine 20 can be used to improve the conversion rate of ammonia-hydrogen production and the exhaust gas heat utilization rate, and the ammonia reaction hydrogen production device 40 can be protected from overheating by controlling the opening of the bypass valve 3, thereby ensuring that the ammonia reaction hydrogen production device operates within safe and effective boundary conditions.

[0076] The above is only a preferred specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An ammonia hydrogen fusion engine system, characterized in that: The invention comprises an engine, a liquid ammonia vaporization device, an ammonia reaction hydrogen production device, a hydrogen-nitrogen mixer and an overheating protection device, wherein the engine has an intake manifold and an exhaust manifold, wherein the intake manifold is connected to the hydrogen-nitrogen mixer through a first pipeline, and the exhaust manifold discharges tail gas through a second pipeline, wherein the second pipeline runs through the ammonia reaction hydrogen production device, wherein the interior of the ammonia reaction hydrogen production device is filled with a catalyst, wherein the ammonia reaction hydrogen production device has an inlet end and an outlet end, wherein the inlet end is connected to the liquid ammonia vaporization device through a third pipeline, wherein the liquid ammonia vaporization device is used to vaporize liquid ammonia into ammonia gas, and wherein the outlet end is connected to the hydrogen-nitrogen mixer through a fourth pipeline; The overheat protection device comprises: A bypass branch is arranged in parallel with the ammonia reaction hydrogen production device, one end of the bypass branch is connected to the upstream of the second pipeline, and the other end is connected to the downstream of the second pipeline; A bypass valve is arranged on the bypass branch; a first sensor and a second sensor, wherein the first sensor is disposed upstream of the second pipeline and is used to sense a first temperature of the tail gas, and the second sensor is disposed on the ammonia reaction hydrogen production device and is used to sense a second temperature of the catalyst; and A controller is electrically connected to the first sensor, the second sensor and the bypass valve, and is used to adjust the opening of the bypass valve according to the relationship between the first temperature, the second temperature and a target temperature threshold.

2. The ammonia-hydrogen fusion engine system according to claim 1, characterized in that: The overheat protection device further comprises a heat exchanger, which is arranged on the bypass branch and located upstream of the bypass valve, and is used for performing heat exchange with the exhaust gas entering the bypass branch.

3. The ammonia-hydrogen fusion engine system according to claim 2, characterized in that: The ammonia-hydrogen fusion engine system also includes a liquid supply device, which includes a liquid inlet pipe and a liquid outlet pipe that are interconnected. The heat exchanger has a liquid inlet and a liquid outlet. The liquid inlet pipe is connected to the liquid inlet, and the liquid outlet pipe is connected to the liquid outlet.

4. The ammonia-hydrogen fusion engine system according to claim 1, characterized in that: The ammonia-hydrogen fusion engine system also includes a post-processing device, the ammonia reaction hydrogen production device includes a hydrogen production chamber for accommodating ammonia and a catalyst, the inlet end and the outlet end are arranged in the hydrogen production chamber, and the second pipeline passes through the hydrogen production chamber and then communicates with the post-processing device.

5. The ammonia-hydrogen fusion engine system according to claim 1, characterized in that: A pressure sensor is also provided on the ammonia reaction hydrogen production device. Along the direction from the liquid ammonia vaporization device to the inlet end of the ammonia reaction hydrogen production device, a pressure regulating valve, a first buffer device and an ammonia injection valve are sequentially provided on the third pipeline, and the pressure regulating valve is used to adjust the pressure of the mixed gas containing hydrogen and nitrogen. Along the direction from the outlet end of the ammonia reaction hydrogen production device to the hydrogen-nitrogen mixer, a first filter, a second buffer device and a hydrogen-nitrogen injection valve are sequentially provided on the fourth pipeline.

6. The ammonia-hydrogen fusion engine system according to claim 1, characterized in that: The hydrogen-nitrogen mixer is also connected to an air intake pipe, and the air intake pipe is provided with a second filter for purifying the air.

7. The ammonia-hydrogen fusion engine system according to claim 6, characterized in that: The turbine of the engine is connected to the exhaust manifold, and the turbine is coaxially connected to the compressor; the hydrogen-nitrogen mixer is communicated with the air inlet end of the compressor, and the air outlet end of the compressor is connected to the air inlet manifold through the first pipeline. An intercooler and a throttle are also provided on the first pipeline. The intercooler is used to cool the mixed gas of air, hydrogen, nitrogen and ammonia compressed by the compressor.

8. The ammonia-hydrogen fusion engine system according to claim 1, characterized in that: The liquid ammonia vaporization device includes a liquid ammonia tank, a liquid ammonia pump and a liquid ammonia vaporizer. The liquid ammonia tank is connected to the liquid ammonia vaporizer through the liquid ammonia pump. The cooling water of the engine is connected to the liquid ammonia vaporizer through a fifth pipeline for heat exchange with the liquid ammonia in the liquid ammonia vaporizer. A control valve is provided on the fifth pipeline.

9. A control method for an ammonia-hydrogen fusion engine system, applied to the ammonia-hydrogen fusion engine system according to any one of claims 1 to 8, characterized in that: The control method comprises: Acquiring a first temperature of the exhaust gas sensed by the first sensor and a second temperature of the catalyst sensed by the second sensor; The opening degree of the bypass valve is adjusted according to the relationship between the first temperature, the second temperature and a target temperature threshold.

10. The control method according to claim 9, characterized in that: The step of adjusting the opening of the bypass valve according to the relationship between the first temperature, the second temperature and the target temperature threshold comprises: According to the first temperature being lower than a first temperature threshold and the second temperature being lower than a second temperature threshold, controlling the bypass valve to close; According to the first temperature being higher than the first temperature threshold and the second temperature being higher than the second temperature threshold, the bypass valve is controlled to be opened, and the opening degree of the bypass valve varies linearly with the second temperature.

Images