An integrated injection system for an ammonia fuel engine and its after-treatment system

Abstract

The present invention discloses an integrated injection system for an ammonia fuel engine and its after-treatment system, comprising an ammonia supply module, an engine module, and an ammonia after-treatment module. The integrated injection system for an ammonia fuel engine and its after-treatment system also includes an ammonia metering control module. The ammonia metering control module includes an ammonia inlet end connected to the ammonia supply module, an engine module supply end connected to the engine module and supplying ammonia thereto, and a after-treatment module supply end connected to the ammonia after-treatment module and supplying ammonia thereto. Ammonia is distributed by the ammonia metering control module and the distributed ammonia is respectively introduced into the engine module and the ammonia after-treatment module, thereby meeting the ammonia supply requirements of the engine module and the ammonia after-treatment module.

Description

Technical Field

[0001] The present invention relates to the technical field of ammonia fuel automobile engines, and in particular to an integrated injection system for an ammonia fuel engine and a post-processing system thereof. Background Art

[0002] my country's current energy structure is mainly based on fossil energy, resulting in a series of environmental problems that cannot be ignored due to the greenhouse effect caused by large amounts of carbon dioxide emissions. This has led to demands for clean alternative fuels and the development of sustainable energy. In the past few years, hydrogen has received widespread attention and attention because it only produces water when burned and has no carbon emissions. However, due to its own physical and chemical properties, hydrogen has problems in safety, storage and transportation. This is mainly because hydrogen has a wide ignition range and its flame burns very fast, which makes it easy to have safety problems during storage and transportation. Its transportation cost is also high due to high technical requirements. In addition, hydrogen is easy to diffuse, and it is easy to make the engine structure brittle when used in the engine. Ammonia, as a hydrogen energy carrier, solves the problem of hydrogen's physical and chemical properties very well. Ammonia produces only nitrogen and water when fully burned, and also has no carbon emissions. Its liquefaction temperature is -33°C, making it easy to store and transport, making it a promising green energy carrier. Its energy density is comparable to that of methanol and dimethyl ether, and its volumetric energy density is 33% higher than that of liquefied hydrogen. Currently, ammonia is widely used in fertilizers or as a raw material for synthetic fertilizers. It has excellent basic measures for production, processing, storage and distribution, and is considered to be a commercial energy source with great commercial potential. In addition, ammonia fuel has the characteristics of high octane number, with an octane number greater than 111, which can effectively suppress knock in internal combustion engines, so ammonia-fueled engines can have a higher compression ratio. Moreover, ammonia is a sustainable energy source and can be synthesized from hydrogen and nitrogen through renewable energy sources such as wind or solar energy, but ammonia-fueled engines also face many challenges.

[0003] The patent with application number 202210523255.0 and titled "A Hydrogen-Ammonia Fuel Engine Exhaust After-Treatment System" discloses a hydrogen-ammonia fuel engine exhaust after-treatment system, including an exhaust catalytic device and an ammonia supply device. The exhaust catalytic device is used to convert ammonia NH3 and nitrogen oxides NOX in the exhaust gas, and the ammonia supply device is used to supply ammonia NH3 to the exhaust catalytic device; the exhaust catalytic device includes a first SCR catalyst, a first exhaust pipe, a second SCR catalyst, a second exhaust pipe and an ammonia slip catalyst ASC connected in sequence, the inlet of the first SCR catalyst is connected to the exhaust pipe outlet of the hydrogen-ammonia fuel engine, and the end of the ammonia supply device is installed on the first exhaust pipe.

[0004] Patent application number 202111460076.9, titled "Ammonia-Hybrid Power System and Engine," discloses an ammonia-hydrogen hybrid power system and engine. The ammonia-hydrogen hybrid engine includes: a fuel tank for storing liquid ammonia, including a discharge port; an ammonia catalytic hydrogen production device for catalyzing ammonia to form hydrogen, including an ammonia inlet and a hydrogen discharge port, the ammonia inlet and hydrogen discharge ports being connected; and an ammonia fuel engine, including a main combustion chamber, a jet ignition chamber, and an ignition device. The main combustion chamber is connected to the discharge port, the hydrogen discharge port is connected to the jet ignition chamber, and the ignition device is disposed in the jet ignition chamber, which is in communication with the main combustion chamber.

[0005] None of the currently published patents consider ammonia as an engine fuel source. Liquid ammonia aftertreatment systems utilize exhaust waste heat for heating, making temperature control difficult and significantly impacting precise ammonia control. Furthermore, when ammonia is supplied as an engine fuel, the high total demand makes accurate metering difficult across all operating conditions. This is especially true at low engine loads, where ammonia flow demand is low. Large-range flowmeters have poor metering accuracy at low flow rates. Summary of the Invention

[0006] The purpose of the present invention is to address the deficiencies of the above-mentioned background technology and to provide an integrated injection system for an ammonia fuel engine and its after-treatment system, which can accurately measure the flow demand of the engine under all operating conditions when ammonia is used as the engine fuel source and accurately control the heating temperature of the liquid ammonia after-treatment system.

[0007] To achieve this object, the integrated injection system for an ammonia fuel engine and its after-treatment system designed by the present invention includes an ammonia supply module, an engine module and an ammonia after-treatment module. The integrated injection system for an ammonia fuel engine and its after-treatment system also includes an ammonia metering control module, the ammonia metering control module including an ammonia inlet end connected to the ammonia supply module, an engine module supply end connected to the engine module and providing ammonia thereto, and a after-treatment module supply end connected to the ammonia after-treatment module and providing ammonia thereto; the ammonia metering control module also includes an ammonia distribution device connected to the ammonia inlet end, which provides ammonia to the engine module and the ammonia after-treatment module respectively through the engine supply end and the after-treatment supply end according to the ammonia supply requirements of the engine module and the ammonia after-treatment module, and an ammonia distribution control device that controls the ammonia distribution device.

[0008] Furthermore, the ammonia distribution device includes a large flow metering valve connected to the ammonia inlet end, a small flow metering valve connected between the large flow metering valve and the engine air supply end, and a small flow solenoid valve connected between the large flow metering valve and the after-treatment air supply end.

[0009] Furthermore, a reversing pipeline is connected between the large-flow metering valve and the engine air supply end, and an electromagnetic reversing valve is provided on the reversing pipeline.

[0010] Furthermore, the ammonia distribution control device includes an ACM controller.

[0011] Furthermore, the ammonia supply module includes a liquid ammonia tank, an ammonia inlet pipeline is connected between the liquid ammonia tank and the ammonia inlet end, and the ammonia inlet pipeline is provided with a pipeline on-off device, an ammonia heating device and an ammonia pressure stabilizing device.

[0012] Furthermore, the ammonia inlet pipeline is also provided with an ammonia filter device for filtering impurities in the ammonia.

[0013] Furthermore, the engine module includes an engine connected to a fuel common rail pipeline, an engine air supply pipeline is connected between the engine and the engine air supply end, and a pipeline opening and closing device is provided on the engine air supply pipeline.

[0014] Furthermore, the engine air supply pipeline is also provided with an ammonia filter device for filtering impurities in the ammonia.

[0015] Furthermore, the ammonia after-treatment module includes a DOC oxidation catalyst connected to the exhaust end of the engine module and an SCR+ASC reactor connected to the DOC oxidation catalyst, and a after-treatment air supply pipeline is connected between the air inlet end of the SCR+ASC reactor and the after-treatment air supply end, and a pipeline opening and closing device is provided on the after-treatment air supply pipeline.

[0016] Furthermore, the post-processing gas supply pipeline is also provided with an ammonia filter device for filtering impurities in the ammonia.

[0017] The present invention has the beneficial effect of distributing ammonia through the ammonia metering control module and introducing the distributed ammonia into the engine module and the ammonia post-treatment module, respectively, meeting the ammonia supply requirements of the engine module and the ammonia post-treatment module. The ammonia metering control module utilizes a structure that connects a large-flow metering unit and a small-flow metering unit in series, improving the accuracy of the small-flow ammonia supply requirement and ensuring precise control and calculation of the ammonia supply requirements of the engine module and the ammonia post-treatment module. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of an integrated injection system for an ammonia fuel engine and its after-treatment system according to the present invention;

[0019] Figure 2 Schematic diagram of the ammonia metering control module in the present invention;

[0020] Among them, 1 is an ammonia supply module (1.1 is a liquid ammonia tank), 2 is an ammonia metering control module (2.1 is an ammonia distribution device, 2.2 is an ammonia distribution control device), 3 is an engine module (3.1 is an engine), 4 is an ammonia after-treatment module (4.1 is a DOC oxidation catalyst, 4.2 is an SCR+ASC reactor), 5 is a large flow metering valve, 6 is a small flow metering valve, 7 is a small flow solenoid valve, 8 is a reversing pipe, 9 is a solenoid reversing valve, 10 is a pressure sensor, 11 is an ammonia intake pipe, 12 is an ammonia heating device, 13 is an ammonia pressure stabilizing device, 14 is a fuel common rail pipe, 15 is an engine air supply pipe, 16 is an after-treatment air supply pipe, 17 is a solenoid switch valve, 18 is a filter, 19 is a fuel nozzle, 20 is an ammonia nozzle, 21 is a temperature sensor, and 22 is a NOx sensor. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments.

[0022] like Figure 1 —2 shows an integrated injection system for an ammonia fuel engine and its after-treatment system, comprising an ammonia supply module 1, an engine module 3, an ammonia after-treatment module 4 and an ammonia metering control module 2.

[0023] like Figure 1 As shown, the ammonia supply module 1 includes a liquid ammonia tank 1.1, which is connected to an ammonia inlet pipeline 11. The ammonia inlet pipeline 11 is provided with an electromagnetic switch valve 17, an ammonia heating device 12, an ammonia pressure stabilizing device 13 and a filter 18 for filtering impurities in the ammonia gas. The ammonia pressure stabilizing device 13 is connected to a pressure sensor 10 and a temperature sensor 21.

[0024] like Figure 1 As shown in FIG. 2 , the ammonia metering control module 2 includes an ammonia distribution device 2.1 connected to the ammonia inlet pipeline 11 and an ammonia distribution control device 2.2 for controlling the ammonia distribution device 2.1. Figure 2 As shown, ammonia distribution device 2.1 includes a high-flow metering valve 5 connected to ammonia inlet line 11, a low-flow metering valve 6 connected between high-flow metering valve 5 and the engine air supply (small-flow metering valve 6 is connected to engine air supply line 15), and a low-flow solenoid valve 7 connected between high-flow metering valve 5 and the after-treatment air supply (small-flow solenoid valve 7 is connected to after-treatment air supply line 16). A reversing line 8 is connected between high-flow metering valve 5 and the engine air supply, and a solenoid reversing valve 9 is installed on reversing line 8. Ammonia distribution control device 2.2 can be an ACM controller.

[0025] like Figure 1 As shown, the engine module 3 includes an engine 3.1 connected to a fuel common rail line 14. An engine air supply line 15 is connected between the engine 3.1 and the large flow metering valve 5. The engine air supply line 15 is provided with an electromagnetic switch valve 17 and a filter 18 for filtering impurities in ammonia gas.

[0026] like Figure 1 As shown, the ammonia after-treatment module 4 includes a DOC oxidation catalyst 4.1 connected to the exhaust end of the engine module 3 and an SCR+ASC reactor 4.2 connected to the DOC oxidation catalyst 4.1. An after-treatment air supply pipeline 16 is connected between the air inlet end of the SCR+ASC reactor 4.2 and the large-flow metering valve 5. The after-treatment air supply pipeline 16 is provided with a small-flow solenoid valve 7, an electromagnetic switch valve 17 and a filter 18 for filtering impurities in the ammonia.

[0027] In the present invention, the liquid ammonia tank 1.1 provides a source of ammonia for the entire system. The liquid ammonia tank 1.1 is a standard liquid ammonia tank. When the liquid ammonia is exhausted, the tank body can be directly replaced, which is convenient and quick to operate. The electromagnetic switch valve 17 connected to the ammonia inlet pipe 11 is used to control the supply of ammonia. When the pressure of the pressure sensor 10 is detected to be less than a certain threshold, ammonia is replenished in time. The ammonia heating device 12 is used to heat liquid ammonia to release ammonia, and the on and off of the ammonia heating device 12 is controlled according to the temperature sensor 21 and the pressure sensor 10. The ammonia pressure stabilizing device 13 provides ammonia pressure stabilization and provides precise injection conditions for the ammonia distribution device 2.1. The temperature sensor 21 and the pressure sensor 10 are used to monitor the temperature and pressure of ammonia in the ammonia pressure stabilizing device 13. The filter 18 is used to filter impurities in each section of ammonia. The ACM controller (ammonia distribution control device 2.2) is used for the execution control of the entire ammonia injection system and the OBD fault diagnosis of the entire system. The ammonia distribution device 2.1 can control the metering solenoid valve inside it according to the ECU instructions, and the ACM controller can achieve the injection amount required by the engine and after-treatment. The electromagnetic switch valve 17 is used to cut off the ammonia supply. The fuel common rail line 14 can provide high-pressure fuel to the fuel nozzle 19, which is mixed and burned with ammonia in the combustion chamber of the engine 3.1. The ammonia nozzle 20 injects ammonia into the ammonia after-treatment module 4 to react with NOx in the exhaust gas to produce nitrogen and water. The NOx sensor 22 is used to detect the NOx value before and after after-treatment to achieve closed-loop control of ammonia injection. The DOC oxidation catalyst 4.1 is used to oxidize part of the NO to produce NO2. The SCR+ASC reactor 20 can provide a catalyst, which reacts with NOx under the action of ammonia to produce nitrogen and water and remove excess ammonia.

[0028] like Figure 2As shown, the implementation of ammonia distribution device 2.1 is as follows: High-flow metering valve 5 is primarily used to meter ammonia supplied to engine 3.1. Due to the inaccurate metering of low-flow ammonia, low-flow metering valve 6 is required for metering. When engine 3.1 requires high-flow ammonia injection, high-flow metering valve 5 measures the amount, and solenoid reversing valve 9 is adjusted to allow it to flow to engine 3.1. When engine 3.1 requires low-flow injection, solenoid reversing valve 9 is adjusted to connect high-flow metering valve 5 to low-flow metering valve 2 before it flows to engine 3.1.

[0029] The flow rate requirement of the ammonia post-processing module 4 is a small flow rate, which can be measured by the small flow solenoid valve 7.

[0030] In the present invention, ammonia is distributed through the ammonia metering control module 2 and introduced into the engine module 3 and the ammonia post-processing module 4, respectively, to meet the ammonia supply requirements of the engine module 3 and the ammonia post-processing module 4. The ammonia metering control module 2 adopts a structure in which a large-flow metering unit and a small-flow metering unit are connected in series, which improves the accuracy of the small-flow ammonia supply requirement and ensures precise control and calculation of the ammonia supply requirements of the engine module 3 and the ammonia post-processing module 4.

[0031] It should be noted that the description of the above technical solutions is illustrative only. This specification may be embodied in various forms and should not be construed as limiting the technical solutions set forth herein. Rather, these descriptions are provided to ensure that the disclosure of the present invention is thorough and complete and to fully convey the scope of the disclosure to those skilled in the art. Furthermore, the technical solutions of the present invention are limited only by the scope of the claims.

[0032] When a detailed description of related known functions or configurations is determined to unnecessarily obscure the focus of the specification and claims, the detailed description will be omitted.

[0033] When “including,” “having,” and “comprising” are used in this specification, unless otherwise used, there may also be another part or other parts, and the terms used may generally be singular but may also represent plural forms.

[0034] Finally, it should be noted that the above embodiments are merely representative examples of the present invention. Obviously, the present invention is not limited to the above embodiments and is susceptible to numerous variations. Any simple modifications, equivalent variations, and modifications to the above embodiments based on the technical essence of the present invention shall be deemed to fall within the scope of protection of the present invention.

Claims

1. An integrated injection system for an ammonia fuel engine and its after-treatment system, comprising an ammonia supply module (1), an engine module (3) and an ammonia after-treatment module (4), characterized in that: It also includes an ammonia metering control module (2), the ammonia metering control module (2) including an ammonia inlet end connected to the ammonia supply module (1), an engine module air supply end connected to the engine module (3) and supplying ammonia thereto, and a post-processing module air supply end connected to the ammonia post-processing module (4) and supplying ammonia thereto; the ammonia metering control module (2) also includes an ammonia inlet end connected to the ammonia supply module (1), and supplying ammonia to the engine module (3) and the ammonia post-processing module (4) through the engine module air supply end and the post-processing module air supply end, respectively. The block (4) provides an ammonia distribution device (2.1) for providing ammonia and an ammonia distribution control device (2.2) for controlling the ammonia distribution device (2.1); the ammonia distribution device (2.1) includes a large flow metering valve (5) connected to the ammonia inlet end, a small flow metering valve (6) connected between the large flow metering valve (5) and the engine module air supply end, and a small flow electromagnetic valve (7) connected between the large flow metering valve (5) and the after-treatment module air supply end; a reversing pipeline (8) is connected between the large flow metering valve (5) and the engine module air supply end, and an electromagnetic reversing valve (9) is provided on the reversing pipeline (8).

2. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 1, characterized in that: The ammonia distribution control device (2.2) includes an ACM controller.

3. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 1, characterized in that: The ammonia supply module (1) comprises a liquid ammonia tank (1.1), an ammonia inlet pipeline (11) is connected between the liquid ammonia tank (1.1) and the ammonia inlet end, and the ammonia inlet pipeline (11) is provided with a pipeline on-off device, an ammonia heating device (12) and an ammonia pressure stabilizing device (13).

4. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 3, characterized in that: The ammonia gas inlet pipeline (11) is also provided with an ammonia gas filtering device for filtering impurities in the ammonia gas.

5. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 1, characterized in that: The engine module (3) comprises an engine (3.1) connected to a fuel common rail pipeline (14); an engine air supply pipeline (15) is connected between the engine (3.1) and an air supply end of the engine module; and a pipeline on-off device is provided on the engine air supply pipeline (15).

6. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 5, characterized in that: The engine air supply pipeline (15) is also provided with an ammonia filter device for filtering impurities in the ammonia.

7. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 1, characterized in that: The ammonia after-treatment module (4) comprises a DOC oxidation catalyst (4.1) connected to the exhaust end of the engine module (3) and an SCR+ASC reactor (4.2) connected to the DOC oxidation catalyst (4.1); an after-treatment air supply pipeline (16) is connected between the air inlet end of the SCR+ASC reactor (4.2) and the air supply end of the after-treatment module; and a pipeline on-off device is provided on the after-treatment air supply pipeline (16).

8. The integrated injection system for an ammonia fuel engine and its after-treatment system according to claim 7, characterized in that: The post-processing gas supply pipeline (16) is also provided with an ammonia filter device for filtering impurities in the ammonia.

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