An ammonia diesel engine with multiple liquid ammonia injection points in the intake duct and a post-processing ammonia supply system

Abstract

The present application relates to an ammonia diesel engine with multiple points of liquid ammonia injection in the intake passage and a post-processing ammonia supply system, including: an ammonia diesel engine, which includes an intake passage and an exhaust passage, the exhaust port of the exhaust passage is connected to a turbine, the turbine is connected to a compressor, and a first intercooler is connected between the compressor and the intake port of the intake passage; an ammonia supply system, which includes a liquid ammonia storage tank, the liquid ammonia storage tank is connected to the first intercooler through a first ammonia supply pipeline, the liquid ammonia storage tank is connected to a liquid ammonia supply rail through a second ammonia supply pipeline, and the liquid ammonia supply rail is connected to a liquid ammonia nozzle for spraying liquid ammonia into multiple points in the intake passage. In the present application, the liquid ammonia entering the first intercooler exchanges heat with the compressed fresh air entering the first intercooler, so that the liquid ammonia absorbs heat and then vaporizes. The compressed fresh air exchanges heat with the liquid ammonia, and the temperature of the compressed fresh air is further reduced. The intake temperature of the ammonia diesel engine further improves the NOx emission of the ammonia diesel engine and reduces the nitrogen oxide emission of the engine.

Description

Technical Field

[0001] The present application relates to the technical field of dual-fuel engines, and in particular to an ammonia-diesel engine with multi-point liquid ammonia injection in the intake duct and a post-processing ammonia supply system. Background Art

[0002] At present, motor vehicle exhaust emissions have become an important factor affecting air pollution. NOx is one of the main pollutants in exhaust emissions. Automobile exhaust control and pollution control have become an important part of sustainable development. Diesel vehicles are the main contributors to mobile source pollution. Although diesel vehicles only account for 10% of my country's motor vehicle ownership, their NOx emissions are close to 70% of the total motor vehicle emissions. In order to effectively control air pollution, the state has promulgated relevant regulations to improve the emission level of motor vehicles.

[0003] NOx in automobile exhaust is the product of chemical reaction between N2 in the air and O2 in the high temperature environment in the cylinder. A large number of studies have shown that reducing the combustion temperature in the cylinder can significantly reduce NOx emissions. In addition, the supercharger is a key component of the diesel engine. The intake air has a high temperature after being supercharged by the supercharger. Even after being cooled by the intercooler, the intake air temperature is still relatively high. Therefore, reducing the intake air temperature is of great significance to improving the NOx emissions of diesel engines.

[0004] In the context of "carbon neutrality", ammonia, as a 100% renewable zero-carbon fuel, can power ships, trucks and engineering vehicles, and has great potential in the transition from fossil fuels to zero-carbon fuels. Ammonia is an easily liquefied gas. When cooled to -33.4°C at normal pressure or pressurized to 7-8 atmospheres at normal temperature, ammonia will liquefy into a colorless liquid. The easy liquefaction and zero-carbon properties of ammonia make it very suitable as a fuel for internal combustion engines.

[0005] The latent heat of vaporization of liquid ammonia is 1371KJ / kg, and the latent heat of vaporization of diesel is 375KJ / kg. Therefore, when using liquid ammonia as fuel, its higher latent heat of vaporization can be used to reduce the intake temperature and thus improve NOx emissions.

[0006] For the existing patents on reducing the intake temperature, please refer to the Chinese patent: CN108049965A, a clean engine with an intake water injection function. The patent discloses an engine with an intake water injection function, which includes a two-stage supercharging system, a water injection system, an EGR system, a control system and an engine body. By introducing a large proportion of EGR to dilute the intake oxygen concentration, low-temperature combustion is achieved to reduce NOx emissions; by using the intake water injection, the latent heat of water vaporization is used to further reduce the combustion temperature in the cylinder, so that the engine NOx emissions are close to zero.

[0007] Existing patents related to turbocharging and intercooling can refer to Chinese patent: CN106545405B, a hybrid intercooler system using multiple cooling media and a control method thereof. A hybrid intercooler system using multiple cooling media includes: a first cooler for cooling air pressurized in a turbocharger using transmission oil; a second cooler for cooling the pressurized air passing through the first cooler using cooling water; and a third cooler for cooling the pressurized air passing through the second cooler using outdoor air.

[0008] The typical technical scheme for the existing urea liquid post-treatment system can be referred to in Chinese patent: CN21157362U, a urea injection system and vehicle. By adding urea solution into the exhaust system, urea is hydrolyzed into ammonia under high temperature, and ammonia reacts with pollutant nitrogen oxides to reduce them to pollution-free nitrogen and water. In this process, the effective substance that truly decomposes the pollutant gas in the exhaust gas is ammonia, and urea is only a carrier form for carrying the required ammonia.

[0009] However, in the related art, a clean engine with an intake water injection function has a large amount of cyclic fuel injection under heavy load, a large maximum explosion pressure in the cylinder, and a small air-fuel ratio. While using water injection to reduce NOx, there will be a problem of increased carbon soot.

[0010] The hybrid intercooler system using multiple cooling media uses transmission oil, cooling water, and air to cool the pressurized air. There are the following problems: the temperature of the transmission oil and cooling water is relatively high in the hot engine state, and the temperature difference of the heat exchange medium is small, resulting in a decrease in the heat exchange rate; and for the air-cooled intercooler, it is difficult to achieve stable efficiency due to changes in outdoor temperature.

[0011] Regarding the application of urea liquid post-treatment system, this technology has the following problems: the solute of urea solution in the tank is easy to precipitate crystals at low temperatures, resulting in the deterioration of the quality of the urea solution and clogging of the injection system pipeline; in addition, the urea solution is prone to freezing in the low temperature environment of northern winter, requiring high-power heating and high energy consumption; the urea solution needs to be above 160°C to decompose into ammonia. At the initial stage of engine startup, ammonia cannot be decomposed under the low temperature environment of the exhaust pipe and the post-treatment system does not work.

[0012] In addition, the mass ratio of ammonia, the active ingredient of urea solution, is only 14.25%, and deionized water is required as a solvent, which consumes a lot of resources; the hydrolysis process of urea emits carbon dioxide, which increases the carbon emissions of tail gas; and the industrial production of urea requires the synthesis of ammonia and carbon dioxide. Summary of the invention

[0013] The embodiment of the present application provides an ammonia-diesel engine with multi-point liquid ammonia injection in the air intake duct and a post-treatment ammonia supply system to solve the problem in the related art that the engine intake has a high temperature after being pressurized by the supercharger, and even after being cooled by the intercooler, the intake temperature is still relatively high, making it difficult to further improve nitrogen oxide emissions.

[0014] In a first aspect, an embodiment of the present application provides an ammonia-diesel engine with multi-point liquid ammonia injection in an intake duct, comprising:

[0015] An ammonia-diesel engine, the ammonia-diesel engine comprising an intake passage and an exhaust passage, the exhaust port of the exhaust passage is connected to a turbine, the turbine is connected to a compressor, and a first intercooler is connected between the compressor and the intake port of the intake passage;

[0016] An ammonia supply system, the ammonia supply system comprising a liquid ammonia storage tank, the liquid ammonia storage tank being connected to the first intercooler via a first ammonia supply pipeline, the liquid ammonia storage tank being connected to a liquid ammonia supply rail via a second ammonia supply pipeline, the liquid ammonia supply rail being connected to a liquid ammonia nozzle for spraying liquid ammonia into multiple points in an intake passage.

[0017] In some implementations: the outlet of the liquid ammonia storage tank is connected to a first solenoid valve that controls the on-off of the first and second ammonia supply pipelines, the second ammonia supply pipeline is provided with a second solenoid valve that controls the supply of liquid ammonia to the liquid ammonia supply rail, the first ammonia supply pipeline is provided with a third solenoid valve that controls the supply of liquid ammonia to the first intercooler, and the first solenoid valve, the second solenoid valve and the third solenoid valve are all connected to an electronic control unit.

[0018] In some implementations: a liquid ammonia filter for filtering liquid ammonia is provided on the pipeline between the first solenoid valve and the first ammonia supply pipeline and the second ammonia supply pipeline.

[0019] In some implementations: it also includes a temperature sensor for detecting the operating temperature of the ammonia-diesel engine, and the temperature sensor is connected to the electronic control unit. When the temperature sensor detects that the operating temperature of the ammonia-diesel engine is greater than a set value, the electronic control unit controls the second solenoid valve to open.

[0020] In some implementations: a second intercooler is further connected between the compressor and the air inlet of the air inlet passage, the second intercooler is connected in series with the first intercooler, and the second intercooler is located downstream of the first intercooler in the air flow.

[0021] In some implementations: an EGR system is also included, the EGR system includes an exhaust gas circulation pipe connected between the intake passage and the exhaust passage, the exhaust gas circulation pipe is connected to an EGR valve, and the EGR valve is connected to an electronic control unit.

[0022] In some implementations: it also includes a diesel supply system, the diesel supply system includes a fuel tank, the fuel tank is connected to a high-pressure fuel rail through an engine fuel supply pipeline, the high-pressure fuel rail is connected to a fuel nozzle that sprays oil into a combustion chamber of an ammonia-diesel engine, the engine fuel supply pipeline is connected to a fuel pump, and the fuel pump is connected to an electronic control unit.

[0023] A second aspect of the embodiments of the present application provides a post-processing ammonia supply system, comprising an ammonia-diesel engine with multi-point liquid ammonia injection in the intake duct as described in any of the above embodiments;

[0024] A post-processor is connected to the exhaust port of the turbine, an ammonia supply pipeline is connected between the first intercooler and the post-processor, and an ammonia injection valve is connected to the ammonia supply pipeline.

[0025] In some implementations: an ammonia pressure stabilizing tank is connected to the ammonia supply pipeline between the ammonia injection valve and the first intercooler, and the ammonia injection valve is connected to an electronic control unit.

[0026] In some implementations: the post-processor is provided with a nitrogen oxide sensor for detecting the nitrogen oxide content in the post-processor, and the nitrogen oxide sensor is connected to an electronic control unit;

[0027] The electronic control unit controls the ammonia injection valve to inject ammonia of a set flow rate to the post-processor according to the nitrogen oxide content.

[0028] The beneficial effects of the technical solution provided by this application include:

[0029] An embodiment of the present application provides an ammonia-diesel engine with multi-point liquid ammonia injection in the air intake duct and a post-processing ammonia supply system. Since the ammonia-diesel engine with multi-point liquid ammonia injection in the air intake duct of the present application is provided with an ammonia-diesel engine, the ammonia-diesel engine includes an intake channel and an exhaust channel, the exhaust port of the exhaust channel is connected to a turbine, the turbine is connected to a compressor, and a first intercooler is connected between the compressor and the air intake port of the intake channel; an ammonia supply system, the ammonia supply system includes a liquid ammonia storage tank, the liquid ammonia storage tank is connected to the first intercooler through a first ammonia supply pipeline, the liquid ammonia storage tank is connected to a liquid ammonia supply rail through a second ammonia supply pipeline, and the liquid ammonia supply rail is connected to a liquid ammonia nozzle for spraying liquid ammonia into multiple points in the intake channel.

[0030] Therefore, the ammonia diesel engine with multi-point liquid ammonia injection in the intake duct of the present application is connected with a first intercooler between the compressor of the ammonia diesel engine and the air inlet of the intake duct. The first intercooler is used to cool the compressed fresh air generated by the compressor and send it into the intake duct to participate in the in-cylinder combustion of the ammonia diesel engine to reduce the temperature of the mixed gas in the cylinder. The liquid ammonia storage tank of the ammonia supply system is connected to the first intercooler through the first ammonia supply pipeline. The liquid ammonia entering the first intercooler exchanges heat with the compressed fresh air entering the first intercooler, so that the liquid ammonia absorbs heat and then vaporizes. The compressed fresh air exchanges heat with the liquid ammonia, and the temperature of the compressed fresh air is further reduced. Therefore, reducing the intake temperature of the ammonia diesel engine further improves the NOx emissions of the ammonia diesel engine and reduces the nitrogen oxide emissions of the engine.

[0031] In addition, the liquid ammonia storage tank of the present application is connected to a liquid ammonia supply rail through a second ammonia supply pipeline, and the liquid ammonia supply rail is connected to a liquid ammonia nozzle that sprays liquid ammonia into multiple points in the intake channel. The intake temperature of the ammonia-diesel engine after intercooling is between 35-40°C. After the liquid ammonia nozzle sprays liquid ammonia into the intake channel at multiple points, the liquid ammonia exchanges heat with the fresh air in the intake channel, and the temperature of the fresh air is lowered again. At the same time, the liquid ammonia absorbs heat and vaporizes. Under the action of the airflow, the ammonia and air are fully mixed and enter the cylinder of the ammonia-diesel engine. The electronic control unit determines the diesel injection according to the timing, and the fuel nozzle sprays diesel into the cylinder before the top dead center, so as to realize the diesel spray combustion and then ignite the ammonia in the cylinder. In the dual-fuel combustion mode, diesel spray is used to ignite ammonia to provide power output for the ammonia-diesel engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0033] Figure 1 This is a schematic diagram of the structure of an embodiment of the present application;

[0034] Figure 2 This is a schematic diagram of the structure of the combustion chamber of the ammonia-diesel engine according to an embodiment of the present application.

[0035] Reference numerals:

[0036] 1. Fuel tank; 2. Fuel pump; 3. Ammonia diesel engine; 4. Turbine; 5. Compressor; 6. EGR valve; 7. Liquid ammonia nozzle; 8. Fuel nozzle; 9. Liquid ammonia supply rail; 10. Second intercooler; 11. First intercooler; 12. First solenoid valve; 13. Liquid ammonia storage tank; 14. Third solenoid valve; 15. Second solenoid valve; 16. Liquid ammonia filter; 17. Ammonia pressure regulating tank; 18. Ammonia injection valve; 19. Post-processor; 20. Electronic control unit; L1. Second ammonia supply pipeline; L2. First ammonia supply pipeline; L3. Ammonia supply pipeline. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0038] The embodiment of the present application provides an ammonia-diesel engine with multi-point liquid ammonia injection in the air intake duct and a post-treatment ammonia supply system, which can solve the problem in the related art that the engine intake has a high temperature after being pressurized by the supercharger, and even after being cooled by the intercooler, the intake temperature is still relatively high, making it difficult to further improve nitrogen oxide emissions.

[0039] See also Figure 1 and Figure 2 As shown, the first aspect of the embodiment of the present application provides an ammonia diesel engine with multi-point liquid ammonia injection in the air intake duct, comprising:

[0040] The ammonia diesel engine 3 includes an intake passage and an exhaust passage. A turbine 4 is connected to the exhaust port of the exhaust passage. The high-temperature exhaust gas discharged by the ammonia diesel engine 3 drives the turbine 4 to rotate. The turbine 4 is connected to the compressor 5. The turbine 4 drives the compressor 5 to rotate synchronously at a high speed. The compressor 5 provides compressed fresh air to the intake passage of the ammonia diesel engine 3. A first intercooler 11 is connected between the compressor 5 and the intake port of the intake passage. The first intercooler 11 is used to cool the high-temperature compressed fresh air generated by the compressor 5.

[0041] An ammonia supply system includes a liquid ammonia storage tank 13, which is connected to the first intercooler 11 through a first ammonia supply pipeline L2. The first ammonia supply pipeline L2 passes the liquid ammonia stored in the liquid ammonia storage tank 13 into the first intercooler 11 and then performs heat exchange with the compressed fresh air in the first intercooler 11. The boiling point of liquid ammonia is 28°C at 1.0MPa (gauge pressure), and the latent heat of vaporization is q=1336.97KJ / Kg. Taking advantage of the high latent heat of vaporization of liquid ammonia, liquid ammonia is used as a cooling medium to reduce the temperature of the compressed fresh air. The liquid ammonia storage tank 13 is connected to a liquid ammonia supply rail 9 through a second ammonia supply pipeline L1, and the liquid ammonia supply rail 9 is connected to a liquid ammonia nozzle 7 that sprays liquid ammonia into multiple points in the intake passage.

[0042] The ammonia diesel engine with multiple liquid ammonia injection points in the intake passage of the embodiment of the present application is connected with a first intercooler 11 between the compressor 5 of the ammonia diesel engine 3 and the air inlet of the intake passage. The first intercooler 11 is used to cool the compressed fresh air generated by the compressor 5 and send it into the intake passage to participate in the combustion in the cylinder of the ammonia diesel engine 3 to reduce the temperature of the mixed gas in the cylinder. The liquid ammonia storage tank 13 of the ammonia supply system is connected to the first intercooler 11 through the first ammonia supply pipeline L2. The liquid ammonia entering the first intercooler 11 exchanges heat with the compressed fresh air entering the first intercooler 11, so that the liquid ammonia absorbs heat and then vaporizes. The compressed fresh air exchanges heat with the liquid ammonia, and the temperature of the compressed fresh air is further reduced. Therefore, the intake temperature of the ammonia diesel engine 3 is reduced, the NOx emission of the ammonia diesel engine is further improved, and the nitrogen oxide emission of the engine is reduced.

[0043] In addition, the liquid ammonia storage tank 13 of the embodiment of the present application is connected to the liquid ammonia supply rail 9 through the second ammonia supply pipeline L1, and the liquid ammonia supply rail 9 is connected to the liquid ammonia nozzle 7 for spraying liquid ammonia into multiple points in the intake channel. The intake temperature of the ammonia diesel engine 3 after intercooling is between 35-40°C. After the liquid ammonia nozzle 7 sprays liquid ammonia into the intake channel at multiple points, the liquid ammonia exchanges heat with the fresh air in the intake channel, and the temperature of the fresh air is lowered again. At the same time, the liquid ammonia absorbs heat and vaporizes. Under the action of the airflow, the ammonia and the fresh air are fully mixed and enter the cylinder of the ammonia diesel engine. The electronic control unit 20 determines the diesel injection according to the timing, and the fuel nozzle 8 sprays diesel into the cylinder before the top dead center, so as to realize the diesel spray combustion and then ignite the ammonia in the cylinder. In the dual-fuel combustion mode, diesel spray is used to ignite ammonia to provide power output for the ammonia diesel engine.

[0044] In some optional implementations: See Figure 1 and Figure 2As shown, the embodiment of the present application provides an ammonia diesel engine with multiple points of liquid ammonia injection in the intake duct, and the outlet of the liquid ammonia storage tank 13 of the ammonia diesel engine with multiple points of liquid ammonia injection in the intake duct is connected to a first solenoid valve 12 for controlling the on-off of the first ammonia supply pipeline L2 and the second ammonia supply pipeline L1. The second ammonia supply pipeline L1 is provided with a second solenoid valve 15 for controlling the supply of liquid ammonia to the liquid ammonia supply rail 9, and the first ammonia supply pipeline L2 is provided with a third solenoid valve 14 for controlling the supply of liquid ammonia to the first intercooler 11. The first solenoid valve 12, the second solenoid valve 15 and the third solenoid valve 14 are all connected to the electronic control unit 20.

[0045] A liquid ammonia filter 16 for filtering liquid ammonia is provided on the pipeline between the first solenoid valve 12 and the first ammonia supply pipeline L2 and the second ammonia supply pipeline L2. The liquid ammonia filter 16 is used to filter the liquid ammonia supplied by the liquid ammonia storage tank 13. The liquid ammonia flows into the liquid ammonia filter 16 under pressure, and the impurities in the liquid ammonia will be filtered here. The embodiment of the present application also includes a temperature sensor (not shown) for detecting the working temperature of the ammonia diesel engine 3. The temperature sensor is connected to the electronic control unit 20. When the temperature sensor detects that the working temperature of the ammonia diesel engine 3 is greater than the set value, the electronic control unit 20 controls the second solenoid valve 15 to open. Under the starting condition of the ammonia diesel engine 3, because the temperature of the whole machine is relatively low, the pure diesel mode is adopted to facilitate starting. At this time, the electronic control unit 20 controls the second solenoid valve 15 to close it.

[0046] The electronic control unit 20 determines the oil temperature and cooling water temperature values ​​according to the temperature sensor. When the engine is warmed up, the electronic control unit 20 controls the second solenoid valve 15 to open, and then switches to the dual-fuel mode. The electronic control unit 20 controls the first solenoid valve 12 to open, and the liquid ammonia flows into the liquid ammonia filter 16 under pressure, and the impurities in the liquid ammonia will be filtered here. The filtered liquid ammonia is divided into two paths and flows through the third solenoid valve 14 and the second solenoid valve 15 respectively. The electronic control unit 20 controls the second solenoid valve 15 to open, and the second ammonia supply pipeline L1 enters the liquid ammonia supply rail 9. The liquid ammonia supply rail 9 plays a role in stabilizing the pressure of liquid ammonia. The electronic control unit 20 controls the opening and closing of the liquid ammonia nozzle 7 according to the timing to realize multi-point liquid ammonia injection in the intake duct. At the moment when the intake valve opens, the electronic control unit 20 controls the liquid ammonia nozzle 7 to spray liquid ammonia into the intake passage, and the injection pressure is 1MPa.

[0047] In some optional implementations: See Figure 1As shown, the embodiment of the present application provides an ammonia diesel engine with liquid ammonia injection at multiple points in the air intake duct, and a second intercooler 10 is also connected between the compressor 5 of the ammonia diesel engine with liquid ammonia injection at multiple points in the air intake duct and the air inlet of the air intake duct. The second intercooler 10 is connected in series with the first intercooler 11, and the second intercooler 10 is located downstream of the air flow of the first intercooler 11. The second intercooler 10 is used to further cool the compressed fresh air cooled by the first intercooler 11. The second intercooler 10 uses air as a cooling medium to further cool the compressed fresh air. The compressed fresh air cooled by the second intercooler 10 eventually enters the combustion chamber of the ammonia diesel engine 3 to participate in combustion. The first intercooler 11 using liquid ammonia as the intercooling medium reduces the intake temperature, thereby reducing the heat exchange load of the second intercooler 10 in the air-cooled form, so the volume of the second intercooler 10 can be reduced.

[0048] In some optional implementations: See Figure 1 As shown, the embodiment of the present application provides an ammonia diesel engine with multi-point liquid ammonia injection in the intake passage, and the ammonia diesel engine with multi-point liquid ammonia injection in the intake passage also includes an EGR system, and the EGR system includes an exhaust gas circulation pipe L4 connected between the intake passage and the exhaust passage, and an EGR valve 6 is connected to the exhaust gas circulation pipe L4, and the EGR valve 6 is connected to an electronic control unit 20. The exhaust gas discharged from the exhaust passage enters the intake passage through the EGR valve 6 to mix and exchange heat with air and liquid ammonia. Since the exhaust gas contains a large amount of polyatomic gases such as CO2, and gases such as CO2 cannot burn but absorb a large amount of heat due to their high specific heat capacity, the maximum combustion temperature of the mixed gas in the cylinder is reduced, thereby reducing the amount of NOx generated.

[0049] In some optional implementations: See Figure 1 and Figure 2 As shown, the embodiment of the present application provides an ammonia diesel engine with multiple points of liquid ammonia injection in the intake duct, and the ammonia diesel engine with multiple points of liquid ammonia injection in the intake duct also includes a diesel supply system, and the diesel supply system includes a fuel tank 1, and the fuel tank 1 is connected to the high-pressure fuel rail through the engine fuel supply pipeline. The high-pressure fuel rail is connected to a fuel nozzle 8 that injects oil into the combustion chamber of the ammonia diesel engine 3, and the engine fuel supply pipeline is connected to a fuel pump 2, and the fuel pump 2 is connected to an electronic control unit 20. The electronic control unit 20 controls the fuel pump 2 to supply the diesel in the fuel tank 1 to the fuel nozzle 8 for combustion in the cylinder.

[0050] See also Figure 1 As shown, the second aspect of the embodiment of the present application provides a post-processing ammonia supply system, including an ammonia-diesel engine with multi-point liquid ammonia injection in the intake duct as described in any of the above embodiments, and:

[0051] The post-processor 19 is connected to the exhaust port of the turbine 4. An ammonia supply pipeline L3 is connected between the first intercooler 11 and the post-processor 19, and an ammonia injection valve 18 is connected to the ammonia supply pipeline L3. An ammonia pressure stabilizing tank 17 is connected to the ammonia injection valve 18 and the first intercooler 11. The ammonia injection valve 18 is connected to an electronic control unit 20. The post-processor 19 is provided with a nitrogen oxide sensor (not shown) for detecting the nitrogen oxide content in the post-processor 19. The nitrogen oxide sensor is connected to the electronic control unit 20. The electronic control unit 20 controls the ammonia injection valve 18 to inject a set flow of ammonia into the post-processor 19 according to the nitrogen oxide content.

[0052] The post-treatment ammonia supply system includes an ammonia pressure-stabilizing tank 17, an ammonia injection valve 18, and a post-processor 19. The post-processor 19 is connected to the exhaust port of the turbine 4, and the exhaust gas is discharged into the atmosphere after being purified by the post-processor 19. The post-treatment ammonia supply system is connected to the ammonia pressure-stabilizing tank 17 and the ammonia injection valve 18. Liquid ammonia absorbs heat and changes into a gaseous state after passing through the first intercooler 11. The gaseous ammonia enters the ammonia pressure-stabilizing tank 17 for pressure stabilization, and then is sprayed into the post-processor 19 by the ammonia injection valve 18 to participate in the reduction reaction of nitrogen oxides. Compared with urea as a post-treatment reducing agent, the use of ammonia as a post-treatment reducing agent is more efficient. Compared with the mixing of liquid urea or liquid ammonia with exhaust gas, gaseous ammonia and exhaust gas are easier to mix evenly, thereby improving the SCR catalytic reduction efficiency.

[0053] How it works

[0054] An embodiment of the present application provides an ammonia-diesel engine with multi-point liquid ammonia injection in the air intake duct and a post-processing ammonia supply system. The ammonia-diesel engine with multi-point liquid ammonia injection in the air intake duct of the present application is provided with an ammonia-diesel engine 3, which includes an air intake channel and an exhaust channel, the exhaust port of the exhaust channel is connected to a turbine 4, the turbine 4 is connected to a compressor 5, and a first intercooler 11 is connected between the compressor 5 and the air intake port of the air intake channel; an ammonia supply system, which includes a liquid ammonia storage tank 13, the liquid ammonia storage tank 13 is connected to the first intercooler 11 through a first ammonia supply pipeline L2, the liquid ammonia storage tank 13 is connected to a liquid ammonia supply rail 9 through a second ammonia supply pipeline L1, and the liquid ammonia supply rail 9 is connected to a liquid ammonia nozzle 7 for spraying liquid ammonia into multiple points in the air intake channel.

[0055] Therefore, the ammonia diesel engine with multi-point liquid ammonia injection in the intake duct of the present application is connected with a first intercooler 11 between the compressor 5 of the ammonia diesel engine and the air inlet of the intake duct. The first intercooler 11 is used to cool the compressed fresh air generated by the compressor 5 and send it into the intake duct to participate in the in-cylinder combustion of the ammonia diesel engine 3 to reduce the temperature of the mixed gas in the cylinder. The liquid ammonia storage tank 13 of the ammonia supply system is connected to the first intercooler 11 through the first ammonia supply pipeline L2. The liquid ammonia entering the first intercooler 11 exchanges heat with the compressed fresh air entering the first intercooler 11, so that the liquid ammonia absorbs heat and then vaporizes. The compressed fresh air exchanges heat with the liquid ammonia, and the temperature of the compressed fresh air is further reduced. Therefore, reducing the intake temperature of the ammonia diesel engine 3 further improves the NOx emissions of the ammonia diesel engine 3 and reduces the nitrogen oxide emissions of the engine.

[0056] In addition, the liquid ammonia storage tank of the present application is connected to a liquid ammonia supply rail 9 through a second ammonia supply pipeline L1, and the liquid ammonia supply rail 9 is connected to a liquid ammonia nozzle 7 that sprays liquid ammonia into multiple points in the intake channel. The intake temperature of the ammonia diesel engine 3 after intercooling is between 35-40°C. After the liquid ammonia nozzle 7 sprays liquid ammonia into multiple points in the intake channel, the liquid ammonia exchanges heat with the fresh air in the intake channel, and the temperature of the fresh air is lowered again. At the same time, the liquid ammonia absorbs heat and vaporizes. Under the action of the airflow, the ammonia and the air are fully mixed and enter the cylinder of the ammonia diesel engine 3. The electronic control unit 20 determines the diesel injection according to the timing, and the fuel nozzle 8 sprays diesel into the cylinder before the top dead center, so as to realize the diesel spray combustion and then ignite the ammonia in the cylinder. In the dual-fuel combustion mode, diesel spray is used to ignite ammonia to provide power output for the ammonia diesel engine.

[0057] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application 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 cannot be understood as a limitation on the present application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0058] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0059] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A post-processing ammonia supply system, characterized in that: Ammonia diesel engine including multi-point liquid ammonia injection in the intake duct: A post-processor (19), the post-processor (19) being connected to an exhaust port of the turbine (4), an ammonia supply pipeline (L3) being connected between the first intercooler (11) and the post-processor (19), and an ammonia injection valve (18) being connected to the ammonia supply pipeline (L3); The ammonia diesel engine with multiple liquid ammonia injection points in the air intake passage comprises: An ammonia-diesel engine (3), the ammonia-diesel engine (3) comprising an intake passage and an exhaust passage, the exhaust port of the exhaust passage being connected to a turbine (4), the turbine (4) being connected to a compressor (5), and a first intercooler (11) being connected between the compressor (5) and the intake port of the intake passage; An ammonia supply system, the ammonia supply system comprising a liquid ammonia storage tank (13), the liquid ammonia storage tank (13) being connected to the first intercooler (11) via a first ammonia supply pipeline (L2), The liquid ammonia storage tank (13) is connected to a liquid ammonia supply rail (9) via a second ammonia supply pipeline (L1), and the liquid ammonia supply rail (9) is connected to a liquid ammonia nozzle (7) for spraying liquid ammonia into multiple points in the air intake channel.

2. A post-processing ammonia supply system according to claim 1, characterized in that: The outlet of the liquid ammonia storage tank (13) is connected to a first solenoid valve (12) for controlling the on / off of the first ammonia supply pipeline (L2) and the second ammonia supply pipeline (L1); the second ammonia supply pipeline (L1) is provided with a second solenoid valve (15) for controlling the supply of liquid ammonia to the liquid ammonia supply rail (9); the first ammonia supply pipeline (L2) is provided with a third solenoid valve (14) for controlling the supply of liquid ammonia to the first intercooler (11); the first solenoid valve (12), the second solenoid valve (15) and the third solenoid valve (14) are all connected to an electronic control unit (20).

3. A post-processing ammonia supply system as claimed in claim 2, characterized in that: A liquid ammonia filter (16) for filtering liquid ammonia is provided on the pipeline between the first solenoid valve (12) and the first ammonia supply pipeline (L2) and the second ammonia supply pipeline (L1).

4. A post-processing ammonia supply system as claimed in claim 2, characterized in that: It also includes a temperature sensor for detecting the operating temperature of the ammonia-diesel engine (3), the temperature sensor being connected to the electronic control unit (20), and when the temperature sensor detects that the operating temperature of the ammonia-diesel engine (3) is greater than a set value, the electronic control unit (20) controls the second solenoid valve (15) to open.

5. A post-processing ammonia supply system as claimed in claim 1, characterized in that: A second intercooler (10) is also connected between the compressor (5) and the air inlet of the air inlet passage; the second intercooler (10) is connected in series with the first intercooler (11), and the second intercooler (10) is located downstream of the first intercooler (11) in the air flow.

6. A post-processing ammonia supply system as claimed in claim 1, characterized in that: The invention also includes an EGR system, wherein the EGR system includes an exhaust gas circulation pipe (L4) connected between the intake passage and the exhaust passage, the exhaust gas circulation pipe (L4) is connected to an EGR valve (6), and the EGR valve (6) is connected to an electronic control unit (20).

7. A post-processing ammonia supply system as claimed in claim 1, characterized in that: The invention also comprises a diesel supply system, the diesel supply system comprising a fuel tank (1), the fuel tank (1) being connected to a high-pressure fuel rail via an engine fuel supply pipeline, the high-pressure fuel rail being connected to a fuel nozzle (8) for spraying fuel into a combustion chamber of an ammonia-diesel engine (3), the engine fuel supply pipeline being connected to a fuel pump (2), and the fuel pump (2) being connected to an electronic control unit (20).

8. A post-processing ammonia supply system as claimed in claim 1, characterized in that: An ammonia pressure stabilizing tank (17) is connected to the ammonia supply pipeline between the ammonia injection valve (18) and the first intercooler (11), and the ammonia injection valve (18) is connected to an electronic control unit (20).

9. A post-processing ammonia supply system as claimed in claim 1, characterized in that: The post-processor (19) is provided with a nitrogen oxide sensor for detecting the nitrogen oxide content in the post-processor (19), and the nitrogen oxide sensor is connected to an electronic control unit (20); The electronic control unit (20) controls the ammonia injection valve (18) to inject a set flow of ammonia to the post-processor (19) according to the nitrogen oxide content.

Images