Hydrogen internal combustion engine multistage active and passive processing device based on SCR-ASC coupling technology

Abstract

The utility model relates to a hydrogen internal combustion engine multi-stage active and passive treatment device based on the SCR-ASC coupling technology. The hydrogen internal combustion engine multi-stage active and passive treatment device comprises an exhaust pipe, an electronic control unit (ECU), a selective hydrogen catalytic reduction catalyst, a selective ammonia catalytic reduction catalyst, a hydrogen injector urea injector, a uniform mixer and an ammonia escape catalyst. The hydrogen spraying device, the urea spraying device and the uniform mixer are respectively arranged in the exhaust pipe, and the ECU is respectively in communication connection with the hydrogen spraying device and the urea spraying device. According to the hydrogen internal combustion engine, the uniform mixer and the ammonia escape catalyst are arranged, hydrogen and ammonia can be uniformly mixed through the uniform mixer, reaction is more sufficient, the ammonia escape catalyst is installed at the tail end of the exhaust pipe, redundant ammonia can be removed, the problem of ammonia leakage can be solved, and pollutant emission of the hydrogen internal combustion engine is further reduced.

Description

Technical Field

[0001] This utility model relates to the technical field of hydrogen internal combustion engine treatment devices, and in particular to a multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology. Background Technology

[0002] Selective catalytic reduction (SCR) is the most effective technology for controlling nitrogen oxide (NOx) emissions in mobile sources of internal combustion engines, and it has been successfully applied in fossil fuel internal combustion engines. Based on the type of reducing agent, SCR technology can be classified into NH3-SCR, HC-SCR, H2-SCR, etc. Among them, NH... 3- SCR systems achieve NOx reduction by converting NOx into N2 and H2O through the NH3 generated by the pyrolysis of urea in the exhaust pipe. H2-SCR, on the other hand, is an aftertreatment system that uses H2 as a reducing agent. Pt or Pd are typically used as catalysts to accelerate the redox reaction.

[0003] Chinese patent application CN115506874A discloses a two-stage, active-passive SCR coupled aftertreatment device and its control method for a hydrogen fuel cell internal combustion engine. The device includes a selective hydrogen catalytic reduction catalyst using H2 as a reducing agent and a selective ammonia catalytic reduction catalyst using NH3 as a reducing agent, connected in sequence. A connecting pipe is provided between the selective hydrogen catalytic reduction catalyst and the selective ammonia catalytic reduction catalyst, and this connecting pipe is connected to a urea supply source. An intake pipe for the hydrogen internal combustion engine exhaust gas is provided at the end of the selective hydrogen catalytic reduction catalyst away from the connecting pipe, and this intake pipe is connected to a hydrogen supply source. When using H2 and NH3 as reducing agents, thorough mixing is required for a more complete reaction, which this patent fails to demonstrate. Furthermore, if NH3 is excessive and not treated, it will cause environmental impact; this patent also demonstrates the treatment of excess NH3.

[0004] Therefore, providing a device that can ensure thorough mixing of the reducing agent and handle excess NH3 is an urgent problem to be solved. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology.

[0006] The objective of this utility model can be achieved through the following technical solutions:

[0007] According to one aspect of the present invention, a multi-stage active and passive treatment device for a hydrogen internal combustion engine based on SCR-ASC coupling technology is provided, including an exhaust pipe, an electronic control unit (ECU), a selective hydrogen catalytic reduction catalyst, a selective ammonia catalytic reduction catalyst, a hydrogen injector, and a urea injector. The device further includes a homogenizer and an ammonia escape catalyst.

[0008] The selective hydrogen catalytic reduction catalyst is equipped with exhaust pipes at both ends. The selective hydrogen catalytic reduction catalyst is connected to the selective ammonia catalytic reduction catalyst through the exhaust pipes. The ammonia escape catalyst is connected to the selective ammonia catalytic reduction catalyst. The hydrogen injector, urea injector, and homogenizer are respectively installed in the exhaust pipes. The electronic control unit (ECU) is communicatively connected to the hydrogen injector and the urea injector.

[0009] As a preferred technical solution, the exhaust pipe includes a first exhaust pipe and a second exhaust pipe, which are installed at both ends of the selective hydrogen catalytic reduction catalyst. The selective hydrogen catalytic reduction catalyst is connected to the selective ammonia catalytic reduction catalyst through the second exhaust pipe. The hydrogen injector is installed in the first exhaust pipe, and the urea injector is installed in the second exhaust pipe.

[0010] As a preferred technical solution, the uniform mixer includes a first uniform mixer and a second uniform mixer, wherein the first uniform mixer is installed in a first exhaust pipe and the second uniform mixer is installed in a second exhaust pipe.

[0011] As a preferred technical solution, the first uniform mixer and the second uniform mixer are fans.

[0012] As a preferred technical solution, the device further includes a NOx sensor and a temperature sensor, both of which are installed in the exhaust pipe, and the electronic control unit (ECU) is communicatively connected to the NOx sensor and the temperature sensor respectively.

[0013] As a preferred technical solution, the NOx sensor includes a first NOx sensor and a second NOx sensor. The first NOx sensor is installed in a first exhaust pipe, and the second NOx sensor is installed in a second exhaust pipe. The electronic control unit (ECU) is communicatively connected to the first NOx sensor and the second NOx sensor, respectively.

[0014] As a preferred technical solution, the temperature sensor includes a first temperature sensor and a second temperature sensor. The first temperature sensor is installed in the first exhaust pipe, and the second temperature sensor is installed in the second exhaust pipe. The electronic control unit (ECU) is communicatively connected to the first temperature sensor and the second temperature sensor, respectively.

[0015] As a preferred technical solution, the selective hydrogen catalytic reduction catalyst is a selective hydrogen catalytic reduction catalyst made of Pt-based catalyst, Pd-based catalyst or Rh-based catalyst.

[0016] As a preferred technical solution, the selective ammonia catalytic reduction catalyst is a selective ammonia catalytic reduction catalyst made of Cu-based catalyst, Mn-based catalyst, Fe-based catalyst or V-based catalyst.

[0017] As a preferred technical solution, the ammonia escape catalyst is an ammonia escape catalyst made of Pt-based catalyst.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. This utility model is equipped with a uniform mixer and an ammonia escape catalyst. By using the uniform mixer, hydrogen and ammonia can be mixed evenly, and the reaction is more complete. The ammonia escape catalyst installed at the tail end of the exhaust pipe can remove excess ammonia, alleviate the ammonia leakage problem, and further reduce pollutant emissions from hydrogen internal combustion engines.

[0020] 2. This utility model is equipped with an ECU, a NOx sensor, and a temperature sensor. During the operation of the hydrogen internal combustion engine, the optimal H2 injection quantity and NH3 injection quantity are rationally selected through real-time monitoring and calibration experiments of the internal combustion engine operation, avoiding waste and pollution from excessive injection, and reducing NOx emissions efficiently and environmentally.

[0021] 3. This utility model is equipped with a first NOx sensor, a second NOx sensor, a first temperature sensor, and a second temperature sensor, which are installed on different exhaust pipes, resulting in higher accuracy for local detection and enabling precise control of hydrogen and ammonia release.

[0022] 4. The uniform mixer of this utility model is a fan. Different mixers can be selected according to actual needs. The structures of the first uniform mixer and the second uniform mixer can be different, which provides greater flexibility. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0024] 101. Electronic Control Unit (ECU); 102. Selective Hydrogen Catalytic Reduction Catalyst; 103. Selective Ammonia Catalytic Reduction Catalyst; 104. Ammonia Escape Catalyst; 601. First Temperature Sensor; 602. Second Temperature Sensor; 701. First NOx Sensor; 702. Second NOx Sensor; 801. Hydrogen Injector; 802. Urea Injector; 901. First Homogenizer; 902. Second Homogenizer. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some, not all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present utility model.

[0026] Hydrogen internal combustion engines remove the carbon source from the fuel side, making nitrogen oxides (NOx) the most significant pollutant. Because hydrogen flames propagate faster than traditional fossil fuels, cylinder pressure and temperature rise rapidly in hydrogen internal combustion engines, promoting in-cylinder NOx formation. Lean-burn technology can significantly reduce NOx emissions while avoiding backfire. However, an excessively lean mixture can lead to ignition difficulties, causing unstable engine torque output and affecting driving safety. Aftertreatment devices, as an external technology for internal combustion engines, can minimize the impact on in-cylinder combustion behavior, reducing NOx emissions while ensuring stable power output.

[0027] This invention provides a multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology. The invention incorporates a uniform mixer and an ammonia escape catalyst. The uniform mixer ensures thorough mixing of hydrogen and ammonia, leading to a more complete reaction. The ammonia escape catalyst, installed at the exhaust pipe's tail end, removes excess ammonia, mitigating ammonia leakage and further reducing emissions from the hydrogen internal combustion engine. The invention also includes an ECU, a NOx sensor, and a temperature sensor. During engine operation, real-time monitoring and calibration experiments allow for the optimal selection of H2 and NH3 injection rates, avoiding waste and pollution from excessive injection and efficiently reducing NOx emissions. Furthermore, the invention includes a first NOx sensor, a second NOx sensor, a first temperature sensor, and a second temperature sensor, installed on different exhaust pipes for higher accuracy in localized detection, enabling precise control of hydrogen and ammonia release. The uniform mixer is a fan, allowing for the selection of different mixers. The first and second uniform mixers can employ different structures, providing greater flexibility.

[0028] Example 1

[0029] like Figure 1As shown, a multi-stage active and passive treatment device for a hydrogen internal combustion engine based on SCR-ASC coupling technology includes an exhaust pipe, an electronic control unit (ECU) 101, a selective hydrogen catalytic reduction catalyst 102, a selective ammonia catalytic reduction catalyst 103, a hydrogen injector 801, and a urea injector 802. The device also includes a homogenizer and an ammonia escape catalyst 104.

[0030] The selective hydrogen catalytic reduction catalyst 102 is equipped with exhaust pipes at both ends. The selective hydrogen catalytic reduction catalyst 102 is connected to the selective ammonia catalytic reduction catalyst 103 through the exhaust pipes. The ammonia escape catalyst 104 is connected to the selective ammonia catalytic reduction catalyst 103. The hydrogen injector 801, urea injector 802 and homogenizer are respectively installed in the exhaust pipes. The electronic control unit ECU 101 is communicatively connected to the hydrogen injector 801 and the urea injector 802.

[0031] In this embodiment, H2-SCR is selective hydrogen catalytic reduction catalyst 102, NH3-SCR is selective ammonia catalytic reduction catalyst 103, and ASC is ammonia escape catalyst 104.

[0032] The exhaust pipe includes a first exhaust pipe and a second exhaust pipe, which are installed at both ends of the selective hydrogen catalytic reduction catalyst 102. The selective hydrogen catalytic reduction catalyst 102 is connected to the selective ammonia catalytic reduction catalyst 103 through the second exhaust pipe. The hydrogen injector 801 is installed in the first exhaust pipe, and the urea injector 802 is installed in the second exhaust pipe.

[0033] The homogenizer includes a first homogenizer 901 and a second homogenizer 902, wherein the first homogenizer 901 is installed in a first exhaust pipe and the second homogenizer 902 is installed in a second exhaust pipe.

[0034] The first uniform mixer 901 and the second uniform mixer 902 are fans.

[0035] The device also includes a NOx sensor and a temperature sensor, both of which are installed in the exhaust pipe. The electronic control unit ECU101 is communicatively connected to the NOx sensor and the temperature sensor, respectively.

[0036] The NOx sensor includes a first NOx sensor 701 and a second NOx sensor 702. The first NOx sensor 701 is installed in the first exhaust pipe, and the second NOx sensor 702 is installed in the second exhaust pipe. The electronic control unit ECU 101 is communicatively connected to the first NOx sensor 701 and the second NOx sensor 702 respectively.

[0037] The temperature sensor includes a first temperature sensor 601 and a second temperature sensor 602. The first temperature sensor 601 is installed in the first exhaust pipe, and the second temperature sensor 602 is installed in the second exhaust pipe. The electronic control unit ECU101 is communicatively connected to the first temperature sensor 601 and the second temperature sensor 602 respectively.

[0038] In this embodiment, the upstream side of the H2-SCR102 is connected to the exhaust pipe inlet of the hydrogen internal combustion engine, and the downstream side is connected to the upstream side of the NH3-SCR103; the first temperature sensor 601, the first NOx sensor 701, the hydrogen injector 801, and the first homogenizer 901 are installed from far to near between the upstream side of the H2-SCR102 and the exhaust inlet.

[0039] The upstream side of the NH3-SCR103 is installed on the downstream side of the H2-SCR102, and the downstream side of the NH3-SCR103 is connected to the upstream side of the ASC104; the upstream side of the NH3-SCR103 is equipped with the second temperature sensor 602, the second NOx sensor 702, the urea injector 802, and the second uniform mixer 902 from far to near.

[0040] The upstream side of the ASC 104 is installed on the downstream side of the NH3-SCR103, and the downstream side of the ASC 104 is connected to the main outlet of the exhaust pipe.

[0041] The exhaust gas from the hydrogen internal combustion engine flows through the main exhaust pipe, undergoes a first denitrification process at the H2-SCR102, and then enters the NH3-SCR103 for a second denitrification process before passing through the ASC. 104 Removes excess NH3 and flows into the atmosphere through the main exhaust pipe; the exhaust from the hydrogen internal combustion engine, under the control of the ECU 101, mixes with the additional reducing agent H2 injected by the hydrogen injector 801 and enters the H2-SCR 102; the first homogenizer 901, controlled by the ECU 101, accelerates the mixing of the hydrogen internal combustion engine exhaust with the additional reducing agent H2 injected by the hydrogen injector 801 during hydrogen internal combustion engine startup; the exhaust from the hydrogen internal combustion engine, under the control of the ECU 101, mixes with the additional reducing agent NH3 injected by the urea injector 802 and enters the NH3-SCR 103; the second homogenizer 902, controlled by the ECU 101, accelerates the mixing of the hydrogen internal combustion engine exhaust with the additional reducing agent NH3 injected by the urea injector 802 during hydrogen internal combustion engine startup.

[0042] The ECU101 is connected to the first temperature sensor 601, the second temperature sensor 602, the first NOx sensor 701, the second NOx sensor 702, the hydrogen injector 801, the urea injector 802, the first homogenizer 901, and the second homogenizer 902.

[0043] The first temperature sensor 601 and the second temperature sensor 602 are used to monitor and record the exhaust humidity in the main exhaust pipe upstream of H2-SCR102 and NH3-SCR103. The first NOx sensor 701 and the second NOx sensor 702 are used to monitor and record the exhaust NOx content in the main exhaust pipe upstream of H2-SCR102 and NH3-SCR103. The ECU 101 uses the measured value T from the first temperature sensor 601. i and the measured NOx concentration C of the first NOx sensor 701 n1 The query has completed the calibration of the optimal H2 content C of H2-SCR102. h_in H2 emissions C predicted under hydrogen fuel cell engine operating conditions h1 In comparison, it determines whether H2 needs to be injected into the exhaust and the amount to be injected. The ECU 101 uses the measured value T from the second temperature sensor 602 to determine this. e and the measured NOx concentration C by the second NOx sensor 702 n2 The query has completed the calibration of the optimal urea content C for NH3-SCR 103. NH3_in， Determine whether NH3 needs to be injected into the exhaust gas and the amount to be injected.

[0044] The selective hydrogen catalytic reduction catalyst 102 is made of Pt-based catalyst, Pd-based catalyst or Rh-based catalyst.

[0045] The selective ammonia catalytic reduction catalyst 103 is made of Cu-based catalyst, Mn-based catalyst, Fe-based catalyst or V-based catalyst.

[0046] The ammonia escape catalyst 104 is an ammonia escape catalyst made of Pt-based catalyst.

[0047] In this embodiment, the H2-SCR102 is an example of an SCR coated with a Pt (platinum)-based catalyst, but it can also be an example of an SCR with a Pd (palladium)-based or Rh (rhodium)-based catalyst; the left end of the H2-SCR102 is connected to the downstream of the exhaust pipe of the hydrogen internal combustion engine, and the right end is connected to NH3-SCR103.

[0048] The NH3-SCR103 is exemplified by an SCR coated with a Cu (copper)-based catalyst, but can also be exemplified by an SCR with a Mn (zinc)-based, Fe (iron)-based, or V (vanadium)-based catalyst; the left end of the NH3-SCR103 is connected downstream of H2-SCR102, and the right end is connected to ASC104.

[0049] The ASC104 is exemplified by an ASC coated with a Pt (platinum)-based catalyst; the left end of the ASC104 is connected to the downstream of NH3-SCR103, and the right end is connected to the exhaust pipe outlet.

[0050] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A multi-stage active and passive treatment device for a hydrogen internal combustion engine based on SCR-ASC coupling technology, comprising an exhaust pipe, an electronic control unit (ECU) (101), a selective hydrogen catalytic reduction catalyst (102), a selective ammonia catalytic reduction catalyst (103), a hydrogen injector (801), and a urea injector (802), characterized in that, The device also includes a homogenizer and an ammonia escape catalyst (104); The selective hydrogen catalytic reduction catalyst (102) is equipped with exhaust pipes at both ends. The selective hydrogen catalytic reduction catalyst (102) is connected to the selective ammonia catalytic reduction catalyst (103) through the exhaust pipes. The ammonia escape catalyst (104) is connected to the selective ammonia catalytic reduction catalyst (103). The hydrogen injector (801), urea injector (802) and homogenizer are respectively installed in the exhaust pipes. The electronic control unit (ECU) (101) is communicatively connected to the hydrogen injector (801) and the urea injector (802) respectively.

2. The multi-stage active and passive processing device for hydrogen internal combustion engines based on SCR-ASC coupling technology according to claim 1, characterized in that, The exhaust pipe includes a first exhaust pipe and a second exhaust pipe, which are installed at both ends of the selective hydrogen catalytic reduction catalyst (102). The selective hydrogen catalytic reduction catalyst (102) is connected to the selective ammonia catalytic reduction catalyst (103) through the second exhaust pipe. The hydrogen injector (801) is installed in the first exhaust pipe, and the urea injector (802) is installed in the second exhaust pipe.

3. The multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology according to claim 2, characterized in that, The homogenizer includes a first homogenizer (901) and a second homogenizer (902), wherein the first homogenizer (901) is installed in a first exhaust pipe and the second homogenizer (902) is installed in a second exhaust pipe.

4. The multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology according to claim 3, characterized in that, The first uniform mixer (901) and the second uniform mixer (902) are fans.

5. A multi-stage active and passive treatment device for a hydrogen internal combustion engine based on SCR-ASC coupling technology according to claim 2, characterized in that, The device also includes a NOx sensor and a temperature sensor, both of which are installed in the exhaust pipe. The electronic control unit (ECU) (101) is communicatively connected to the NOx sensor and the temperature sensor, respectively.

6. A multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology according to claim 5, characterized in that, The NOx sensor includes a first NOx sensor (701) and a second NOx sensor (702). The first NOx sensor (701) is installed in a first exhaust pipe, and the second NOx sensor (702) is installed in a second exhaust pipe. The electronic control unit (ECU) (101) is communicatively connected to the first NOx sensor (701) and the second NOx sensor (702) respectively.

7. A multi-stage active and passive treatment device for a hydrogen internal combustion engine based on SCR-ASC coupling technology according to claim 5, characterized in that, The temperature sensor includes a first temperature sensor (601) and a second temperature sensor (602). The first temperature sensor (601) is installed in the first exhaust pipe, and the second temperature sensor (602) is installed in the second exhaust pipe. The electronic control unit (ECU) (101) is communicatively connected to the first temperature sensor (601) and the second temperature sensor (602) respectively.

8. A multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology according to claim 1, characterized in that, The selective hydrogen catalytic reduction catalyst (102) is a selective hydrogen catalytic reduction catalyst (102) made of Pt-based catalyst, Pd-based catalyst or Rh-based catalyst.

9. A multi-stage active and passive treatment device for hydrogen internal combustion engines based on SCR-ASC coupling technology according to claim 1, characterized in that, The selective ammonia catalytic reduction catalyst (103) is a selective ammonia catalytic reduction catalyst (103) made of Cu-based catalyst, Mn-based catalyst, Fe-based catalyst or V-based catalyst.

10. A multi-stage active and passive treatment device for a hydrogen internal combustion engine based on SCR-ASC coupling technology according to claim 1, characterized in that, The ammonia escape catalyst (104) is an ammonia escape catalyst (104) made of Pt-based catalyst.

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