Hydrogen internal combustion engine aftertreatment device, control method and engine

Abstract

The invention provides a hydrogen internal combustion engine aftertreatment device, a control method and an engine, and is applied to the technical field of automobile engines. An intelligent control valve in the hydrogen internal combustion engine aftertreatment device is connected with an exhaust inlet, the input end of an H2SCR and the input end of a first pipeline, and the output end of the first pipeline is connected with the SCR; the output end of the H2SCR is connected with the SCR through a second pipeline; when the exhaust temperature is smaller than a first preset temperature, the intelligent control valve controls the H2SCR to be communicated with the exhaust inlet and controls the first pipeline to be not communicated with the exhaust inlet, NOx in exhaust is converted through the H2SCR, the problems of low-temperature urea crystallization and NOx conversion rate reduction are solved, and when the exhaust temperature is not smaller than the first preset temperature, the intelligent control valve controls the H2SCR to be not communicated with the exhaust inlet and controls the first pipeline to be not communicated with the exhaust inlet. The first pipeline is communicated with the exhaust gas inlet, NOx in exhaust gas is converted through SCR, and the conversion rate of NOx is increased by combining H2SCR and SCR.

Description

Technical Field

[0001] The present application relates to the technical field of automobile engines, and in particular to a hydrogen internal combustion engine aftertreatment device and control method, and an engine. Background Art

[0002] NOx (nitrogen oxides) is a major pollutant in automobile exhaust, which includes nitrogen monoxide (NO), nitrogen dioxide (NO 2 ) and other nitrogen oxides. These compounds are not only harmful to the environment, but also have adverse effects on human health. Therefore, it is crucial to effectively reduce NOx emissions in vehicle exhaust treatment systems.

[0003] Currently, the main method to reduce vehicle NOx emissions is to use Selective Catalytic Reduction (SCR) technology. The SCR system converts NOx into nitrogen and water under the action of a specific catalyst by adding ammonia or urea as a reducing agent. This treatment technology has problems such as low-temperature urea crystallization, resulting in low NOx conversion efficiency in vehicle exhaust. Summary of the invention

[0004] In view of this, the embodiment of the present application provides a hydrogen internal combustion engine post-treatment device and control method, and an engine. In the solution provided by the present application, H is used at low temperature. 2 SCR converts NOx in the exhaust gas to solve the problem of urea crystallization in SCR at low temperature, which reduces the NOx conversion rate. 2 SCR dissipates heat and cools down, thereby increasing H 2 The applicable temperature range of SCR is to use SCR to convert NOx in exhaust gas at medium and high temperatures. 2 SCR and SCR are combined to improve the conversion rate of NOx.

[0005] To achieve the above objectives, the present application provides the following technical solutions:

[0006] A hydrogen internal combustion engine aftertreatment device, comprising:

[0007] Heat dissipation device, NH 3 The selective catalytic reduction (SCR) with H as the reducing agent and 2 Selective hydrogen catalytic reduction catalyst H 2 SCR;

[0008] The input end of the SCR is connected to the output end of the first pipeline and the output end of the second pipeline respectively;

[0009] The H 2 The output end of the SCR is connected to the input end of the second pipeline;

[0010] The H 2 The input end of the SCR and the input end of the first pipeline are both connected to the intelligent control valve;

[0011] The intelligent control valve is used to control the H 2 The conduction state between the input end of the SCR and the input end of the first pipe and the exhaust gas inlet;

[0012] The heat dissipation device is used to 2 SCR dissipates heat.

[0013] The above-mentioned hydrogen internal combustion engine aftertreatment device, optionally, the H 2 The SCR is provided with heat dissipation fins.

[0014] The above-mentioned hydrogen internal combustion engine aftertreatment device, optionally, the heat dissipation device includes:

[0015] Wind regulator;

[0016] The wind force regulator is used to adjust the heat dissipation device to blow toward the H 2 Air flow rate of SCR.

[0017] A method for controlling a hydrogen internal combustion engine aftertreatment device is applied to a hydrogen internal combustion engine aftertreatment device, the method comprising:

[0018] Collecting working status information of the hydrogen internal combustion engine post-processing device in real time;

[0019] When the exhaust temperature in the working state information is lower than the first preset temperature, the exhaust gas to be treated is controlled to first flow through the hydrogen internal combustion engine aftertreatment device with H 2 Selective hydrogen catalytic reduction catalyst H 2 SCR, and then flows through the hydrogen internal combustion engine after-treatment device with NH 3 A selective catalytic reduction (SCR) device is used as the reducing agent, and a preset low-temperature exhaust gas treatment strategy is used to use the H 2 SCR and said SCR treat NOx in the exhaust gas;

[0020] When the exhaust temperature in the working state information is greater than or equal to the first preset temperature, the exhaust gas to be processed is controlled not to flow through the H 2 The SCR directly flows through the SCR and uses a preset high-temperature exhaust gas treatment strategy to control a preset urea nozzle to inject urea and allow the SCR to treat NOx in the exhaust gas.

[0021] In the above method, optionally, the preset low-temperature exhaust gas treatment strategy is used to use the H 2 The SCR and the SCR process NOx in the exhaust gas include:

[0022] Determining whether the exhaust temperature in the working state information is less than or equal to a second preset temperature in the low-temperature exhaust treatment strategy;

[0023] When the exhaust temperature in the working state information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, determining whether the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value in the low-temperature exhaust treatment strategy;

[0024] When the tail NOx value in the working status information is less than or equal to the NOx limit value, the H 2 The SCR performs a reduction treatment on NOx in the exhaust gas, and uses the SCR to reduce the NOx in the exhaust gas. 2 Treat NOx in exhaust gas after SCR treatment;

[0025] When the tail NOx value in the working state information is greater than the NOx limit value, the exhaust gas to be treated flows to the H 2 Before SCR, hydrogen is added to the exhaust gas, using the H 2 The SCR processes NOx in the exhaust gas after the hydrogen is added, and uses the SCR to treat NOx in the exhaust gas after the hydrogen is added. 2 The NOx in the exhaust gas after SCR treatment is treated.

[0026] In the above method, optionally, the step of adding hydrogen to the exhaust gas comprises:

[0027] Obtain hydrogen replenishment parameters;

[0028] The hydrogen replenishment parameter is used to determine a hydrogen replenishment value, and the injection amount of hydrogen injected into the exhaust gas by a preset hydrogen injector is controlled according to the hydrogen replenishment value.

[0029] The above method may optionally further include:

[0030] When the exhaust temperature in the working state information is greater than the second preset temperature in the low temperature exhaust treatment strategy, based on the preset heat dissipation strategy, the heat dissipation device in the hydrogen internal combustion engine aftertreatment device is controlled to heat the H 2 The SCR performs heat dissipation and allows the exhaust gas to pass through the H 2 After the SCR treatment, the exhaust gas is then treated using the SCR.

[0031] In the above method, optionally, the heat dissipation device in the hydrogen internal combustion engine post-processing device is controlled to dissipate heat of the hydrogen based on a preset heat dissipation strategy. 2 SCR performs heat dissipation treatment, including:

[0032] The opening of the wind regulator in the heat dissipation device is controlled to be 100%, so that the gas used for heat dissipation passes through the wind regulator to the H 2 SCR performs heat dissipation and according to the H 2 The temperature change of the SCR adjusts the opening of the wind regulator.

[0033] In the above method, optionally, the controlling a preset urea nozzle to spray urea comprises:

[0034] Get urea supplement parameters;

[0035] The urea replenishment parameter is used to determine a urea injection amount, and the urea nozzle is controlled to inject urea according to the urea injection amount.

[0036] An engine comprises the above-mentioned hydrogen internal combustion engine after-treatment device.

[0037] Compared with the prior art, this application has the following advantages:

[0038] The present application provides a hydrogen internal combustion engine post-treatment device and control method, and an engine, specifically comprising: an intelligent control valve in the hydrogen internal combustion engine post-treatment device is respectively connected to an exhaust inlet, a H 2 The input end of the SCR is connected to the input end of the first pipeline, and the output end of the first pipeline is connected to the SCR. 2 The output end of SCR is connected to SCR through the second pipeline; the intelligent control valve is used to control H 2 The conduction state between the input end of the SCR and the input end of the first pipeline and the exhaust inlet; when the exhaust temperature of the hydrogen internal combustion engine aftertreatment device is lower than the first preset temperature, the intelligent control valve controls the H 2 The input end of the SCR is connected to the exhaust inlet, and the input end of the first pipe is not connected to the exhaust inlet. When the temperature is low, use H 2 SCR converts NOx in the exhaust gas, solves the problem of low NOx conversion rate caused by low-temperature urea crystallization, and improves the NOx conversion rate in the exhaust gas at low temperatures; when the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls H 2 The input end of the SCR is not connected to the exhaust inlet, and the input end of the first pipe is connected to the exhaust inlet, so that when the temperature is high, the SCR is used to convert the NOx in the exhaust. At different temperatures, different NOx conversion methods are used to improve the NOx conversion rate and reduce the NOx emissions of automobile exhaust. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0040] Figure 1 A schematic structural diagram of a hydrogen internal combustion engine post-treatment device provided in an embodiment of the present application;

[0041] Figure 2 An example flow chart of a method for treating a hydrogen internal combustion engine aftertreatment device provided in an embodiment of the present application;

[0042] Figure 3 The use of H provided in the embodiments of this application 2 SCR and SCR process flow diagram for NOx treatment in exhaust gas;

[0043] Figure 4 This is an example diagram of the thermostatic grille being fully opened provided in an embodiment of the present application;

[0044] Figure 5 This is an example diagram of the thermostatic grille being fully closed provided in an embodiment of the present application;

[0045] Figure 6 An example diagram of the opening adjustment of the temperature regulating grille provided in an embodiment of the present application;

[0046] Figure 7 Another flow chart of the control method of the hydrogen internal combustion engine aftertreatment device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising 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, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0049] Terminology explanation:

[0050] SCR: Selective Catalytic Reduction, selective catalytic reduction, NH 3 As a reducing agent;

[0051] H 2 SCR: H 2 A selective hydrogen catalytic reduction catalyst is provided.

[0052] As can be seen from the background technology, the conventional SCR technology is used to treat NOx in automobile exhaust. When the temperature is low, urea crystallization is very likely to occur, which reduces the NOx conversion rate and fails to fully convert the NOx in the exhaust.

[0053] In addition to using SCR technology to treat NOx in exhaust gas, there is also the use of H 2 SCR is a method for treating NOx in exhaust gas. However, this method has low NOx conversion efficiency and a narrow temperature window at medium and high temperatures, and cannot fully convert NOx in exhaust gas at medium and high temperatures.

[0054] In order to solve the above problems, the present application provides a hydrogen internal combustion engine aftertreatment device and a control method. The input end of the SCR in the hydrogen internal combustion engine aftertreatment device of the present application is connected to the output end of the first pipeline and the output end of the second pipeline respectively; 2 The output end of the SCR is connected to the input end of the second pipeline; H 2 The input end of the SCR and the input end of the first pipeline are both connected to the intelligent control valve; the intelligent control valve is used to control H 2 The conduction state between the input end of the SCR and the input end of the first pipeline and the exhaust inlet; when the exhaust temperature in the working state information of the hydrogen internal combustion engine aftertreatment device is less than the first preset temperature, the intelligent control valve controls the H 2 The input end of the SCR is connected to the exhaust inlet, and the input end of the first pipe is not connected to the exhaust inlet. Therefore, H 2 SCR converts NOx in the exhaust gas, and then uses SCR to convert NOx in the exhaust gas. Therefore, when the temperature is low, H 2 SCR converts NOx in the exhaust gas, thereby solving the problem of low-temperature urea crystallization and low NOx conversion rate, and effectively improving the NOx conversion rate in the exhaust gas at low temperatures; when the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls H 2The input end of the SCR is not connected to the exhaust inlet, and the input end of the first pipe is connected to the exhaust inlet, so that when the temperature is high, the SCR is directly used to convert NOx in the exhaust. Therefore, different NOx conversion methods are used at different temperatures to improve the NOx conversion rate and reduce the NOx emissions of automobile exhaust.

[0055] The present application can be used in many general or special computing device environments or configurations, such as personal computers, server computers, handheld or portable devices, tablet devices, multi-processor devices, distributed computing environments including any of the above devices or equipment, etc.

[0056] Reference Figure 1 , is a schematic diagram of the structure of a hydrogen internal combustion engine post-treatment device provided in an embodiment of the present application, and is specifically described as follows:

[0057] The hydrogen internal combustion engine post-treatment device includes: a heat dissipation device 15, a NH 3 The selective catalytic reduction device SCR5 with H as the reducing agent and 2 Selective hydrogen catalytic reduction catalyst H 2 SCR 4.

[0058] The input end of the SCR 5 is connected to the output end of the first pipe 3 and the output end of the second pipe 2 respectively.

[0059] H 2 The output end of SCR 4 is connected to the input end of the second pipe 2; 2 The SCR 5 is provided with heat dissipation fins 11 .

[0060] H 2 The input end of the SCR 4 and the input end of the first pipeline 3 are both connected to the intelligent control valve 10 .

[0061] Intelligent control valve 10 is used to control H 2 The conduction state between the input end of the SCR and the input end of the first pipe 3 and the exhaust gas inlet 1.

[0062] The heat sink 15 is used to heat H 2 SCR 5 for heat dissipation; wherein the heat dissipation device 15 includes a wind regulator 13, an air guide pipe 12 and an air outlet 14; further, the wind regulator 13 can be a temperature regulating grille; the wind regulator is used to adjust the heat dissipation device to blow to H 2 The air flow of SCR 4 is adjusted by controlling the opening of the wind regulator to blow to H 2 Air flow rate of SCR 4.

[0063] Furthermore, a first NOx sensor 9 and a temperature sensor 8 are provided at the exhaust gas inlet 1; the first NOx sensor 9 is used to detect the NOx content in the exhaust gas at the exhaust gas inlet; the temperature sensor 8 is used to detect the temperature of the exhaust gas at the exhaust gas inlet. A urea nozzle 7 is provided at the input end of the SCR 5; a second NOx sensor 6 is provided at the output end of the SCR 5; the second NOx sensor 6 is used to detect the NOx content in the exhaust gas at the output end of the SCR. Preferably, the first NOx sensor can be regarded as a primary NOx sensor, and the second NOx sensor can be regarded as a tail NOx sensor.

[0064] Reference Figure 2 , is a flow chart of a method for treating a hydrogen internal combustion engine aftertreatment device provided in an embodiment of the present application, and is specifically described as follows:

[0065] S201. Collect working status information of a hydrogen internal combustion engine post-processing device in real time.

[0066] The working status information includes but does not participate in the information collected by each sensor in the hydrogen internal combustion engine after-treatment device and the working parameters of each device of the hydrogen internal combustion engine after-treatment device; for example, the exhaust temperature collected by the temperature sensor, the NOx value in the untreated exhaust gas collected by the first NOx sensor (which can be understood as the original exhaust NOx value), and the NOx value in the exhaust gas output from the SCR collected by the second NOx sensor (which can be understood as the tail exhaust NOx).

[0067] S202, determine whether the exhaust temperature in the working status information is greater than or equal to a first preset temperature; when the exhaust temperature in the working status information is less than the first preset temperature, execute S203; when the exhaust temperature in the working status information is greater than or equal to the first preset temperature, execute S204.

[0068] The first preset temperature can be set according to actual needs. For example, the first preset temperature can be set to 250° C. Preferably, when setting the first preset temperature, the SCR NOx conversion efficiency can be close to the lowest temperature of 100%.

[0069] Therefore, when the exhaust temperature is lower than the first preset temperature, H 2 The SCR processes NOx, thereby improving the conversion rate of NOx in the exhaust gas when the exhaust gas temperature is not suitable for the operating temperature of the SCR.

[0070] S203, control the exhaust gas to be treated to first flow through the hydrogen internal combustion engine aftertreatment device with H 2 Selective hydrogen catalytic reduction catalyst H 2 SCR, and then flows through the hydrogen internal combustion engine after-treatment device with NH 3The selective catalytic reduction (SCR) device is used as the reducing agent, and a preset low-temperature exhaust gas treatment strategy is used to use H 2 SCR and SCR treat NOx in exhaust gas.

[0071] In the embodiment provided in the present application, the intelligent control valve is opened, so that the exhaust inlet and the H are controlled by the intelligent control valve. 2 The input end of the SCR is conducting, the exhaust inlet and the input end of the first pipeline are not conducting, the gas flow of the first pipeline is cut off, so that all the exhaust gas at the exhaust inlet 1 passes through the H 2 SCR and second pipe, then flows to SCR.

[0072] Exhaust gas passes through H 2 When SCR, H 2 SCR processes NOx in the exhaust gas, 2 The reactions that occur when SCR treats NOx are as follows:

[0073] 4H 2 +2NO+O 2 → N 2 +4H 2 O (1)

[0074] 2H 2 +O 2 → 2H 2 O (2)

[0075] Furthermore, when using a low temperature exhaust gas treatment strategy, H 2 During the process of SCR and SCR treating NOx in exhaust gas, the urea nozzle does not spray urea, which reduces the conversion cost of NOx. 2 The SCR has a high NOx conversion rate at low temperatures. Therefore, when the temperature is low, the use of H 2 SCR converts NOx in the exhaust gas, solving the problem of SCR low-temperature urea crystallization and low NOx conversion efficiency.

[0076] Further, under the premise that the exhaust temperature in the working state information is lower than the first preset temperature, a low temperature exhaust treatment strategy is used, using H 2 The process of SCR and SCR treating NOx in exhaust gas is as follows Figure 3 The specific instructions are as follows:

[0077] S301. Determine whether the exhaust temperature in the working status information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy. When the exhaust temperature in the working status information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, execute S302; when the exhaust temperature in the working status information is greater than the second preset temperature in the low-temperature exhaust treatment strategy, execute S305.

[0078] It should be noted that the second preset temperature is lower than the first preset temperature, and the second preset temperature can be set according to actual needs. For example, the second preset temperature can be set to 200°C.

[0079] S302, determine whether the tail exhaust NOx value in the working status information is less than or equal to the NOx limit value in the low-temperature exhaust treatment strategy; when the tail exhaust NOx value in the working status information is less than or equal to the NOx limit value, execute S303; when the tail exhaust NOx value in the working status information is greater than the NOx limit value, execute S304.

[0080] The NOx limit value in the low-temperature exhaust treatment strategy can be understood as the tail NOx target value of the hydrogen internal combustion engine aftertreatment device.

[0081] The tail exhaust NOx value in the working status information is detected by the second NOx sensor. The tail exhaust NOx here can be understood as the NOx value of the actual tail exhaust gas of the hydrogen internal combustion engine aftertreatment device.

[0082] S303, use H 2 SCR reduces NOx in the exhaust gas and uses SCR to 2 The NOx in the exhaust gas after SCR treatment is treated.

[0083] S304, the exhaust gas to be treated flows to the H 2 Before SCR, hydrogen is added to the exhaust gas, using H 2 SCR processes NOx in the exhaust gas after hydrogen is added, and uses SCR to 2 The NOx in the exhaust gas after SCR treatment is treated.

[0084] When the tail NOx value in the working status information is less than or equal to the NOx limit value, it means that the unburned H 2 The amount is sufficient to deal with NOx in the exhaust gas, and no additional hydrogen is needed; when the tail NOx value in the working status information is greater than the NOx limit, the NOx emission will be close to the emission limit, which means that the unburned H 2 The amount is insufficient for treating NOx, and additional H 2 .

[0085] The process of replenishing hydrogen to the exhaust gas includes: obtaining hydrogen replenishment parameters; determining a hydrogen replenishment value using the hydrogen replenishment parameters, and controlling the injection amount of hydrogen injected by a preset hydrogen injector to the exhaust gas according to the hydrogen replenishment value; further, the hydrogen replenishment parameters include but are not limited to the difference between the tail exhaust NOx value and the NOx limit value, H 2 The temperature and air velocity of the SCR; based on the hydrogen supplementation parameters in the pre-calibrated H2 The required value MAP determines the requested replenishment value, that is, the additional H required 2 The control unit controls the amount of hydrogen injected to replenish the exhaust gas. Furthermore, the hydrogen injection can be set on the engine cylinder, that is, a small amount of hydrogen is directly sprayed into the combustion chamber during the exhaust stroke. This part of hydrogen will be pushed out of the cylinder and flow into the exhaust tail pipe during the exhaust process. The hydrogen injector can also be set at the front end of the intelligent control valve.

[0086] Therefore, by adding hydrogen to the exhaust gas, H 2 SCR can fully convert NOx in the exhaust gas and improve the NOx conversion rate.

[0087] S305, based on a preset heat dissipation strategy, controlling the heat dissipation device in the hydrogen internal combustion engine post-processing device to heat the H 2 SCR performs heat dissipation and passes the exhaust gas through H 2 After SCR treatment, the exhaust gas is treated with SCR again.

[0088] It should be noted that when the exhaust temperature is greater than the second preset temperature and less than the first preset temperature, S305 is executed, that is, based on the preset heat dissipation strategy, the heat dissipation device in the hydrogen internal combustion engine post-processing device is controlled to heat the H 2 SCR performs heat dissipation treatment, specifically, controlling the opening of the wind regulator in the heat dissipation device to 100%, so that the gas used for heat dissipation passes through the wind regulator to heat H 2 SCR performs heat dissipation and 2 The temperature change of SCR adjusts the opening of the wind regulator. Preferably, H 2 The temperature of the SCR may be an average temperature or a currently detected temperature.

[0089] For example, when the wind regulator is a temperature-adjusting grille, when the exhaust temperature is greater than the second preset temperature and less than the first preset temperature, the opening of the temperature-adjusting grille is 100%, that is, the temperature-adjusting grille is fully open. Figure 4 , is an example diagram of the thermostatic grille being fully opened provided in the embodiment of the present application. 2 After SCR starts to dissipate heat, the opening of the thermostat grille is based on H 2 The SCR temperature changes to adjust, for example: when H 2 When the temperature of the SCR is lower than the second preset temperature and higher than the third preset temperature, the temperature regulating grille is partially opened, that is, the opening degree of the temperature regulating grille is not 100%. Figure 1 The heat dissipation device is shown in the figure, which is an example of a partially open temperature control grille; when H 2 When the temperature of the SCR is less than or equal to the third preset temperature, the opening of the thermostatic grille is zero, that is, the thermostatic grille is completely closed. Figure 5, which is an example diagram of the fully closed temperature regulating grille provided in an embodiment of the present application; the third preset temperature can be set according to actual needs.

[0090] Preferably, the opening of the temperature-adjusting grille can be adjusted with the 2 The SCR temperature is adjusted according to the Figure 6 , is an example diagram of the opening adjustment of the temperature-adjusting grille provided in the embodiment of the present application, in which T3 is the third preset temperature, T2 is the second preset temperature, T1 is the first preset temperature, and Tm is H 2 As can be seen from the figure, the temperature of the SCR can be adjusted linearly when the temperature control grille is opened.

[0091] In the embodiments provided in this application, when H 2 When the temperature of the SCR is less than or equal to the third preset temperature, the temperature regulating grille is completely closed. At this time, the heat dissipation device no longer provides H 2 SCR cooling to prevent H 2 Excessive cooling of the SCR causes H 2 The SCR can be in the temperature range with the highest NOx conversion efficiency and can extend the H 2 The SCR is in the temperature range with the highest NOx conversion efficiency for a certain period of time, thereby improving the NOx conversion rate.

[0092] In the solution provided in the embodiment of the present application, when the exhaust temperature is within the temperature range formed by the second preset temperature and the first preset temperature, as the exhaust temperature increases, H 2 The NOx conversion efficiency of SCR gradually decreases, but in this temperature range, the NOx conversion efficiency of SCR has not yet reached the most efficient area. At this time, H 2 The SCR continues to convert NOx and can use the heat sink to convert H 2 SCR performs heat dissipation to reduce H 2 The temperature of the SCR ensures that H 2 SCR operates in the temperature range where it is most efficient.

[0093] Preferably, after the heat dissipation device is turned on, when H 2 After the temperature of the SCR is less than or equal to the second preset temperature, H 2 During the process of processing NOx in the exhaust gas, SCR needs to detect whether hydrogen needs to be supplemented, such as: detecting whether the tail exhaust NOx value is greater than the NOx limit. When the tail exhaust NOx value is greater than the NOx limit, it is determined that hydrogen needs to be supplemented. The method for determining the amount of hydrogen supplementation refers to the above description and will not be repeated here. When the tail exhaust NOx value is less than or equal to the NOx limit, it is determined that hydrogen does not need to be supplemented.

[0094] S204, control the exhaust gas to be treated not to flow through H 2SCR, flows directly through the SCR, and uses a preset high-temperature exhaust treatment strategy to control the preset urea nozzle to inject urea, and enables the SCR to treat NOx in the exhaust gas.

[0095] In the embodiment provided in the present application, the intelligent control valve is closed, so that the exhaust inlet and H are controlled by the intelligent control valve. 2 The input end of the SCR is not conducting, the exhaust inlet is connected to the input end of the first pipe, and the H 2 The gas flow of the SCR causes all the exhaust gas at the exhaust inlet to flow to the SCR through the first pipe.

[0096] Furthermore, the heat dissipation device is in a closed state.

[0097] The process of controlling the preset urea nozzle to spray urea is as follows: obtaining urea supplementation parameters; using the urea supplementation parameters to determine the urea injection amount, and controlling the urea nozzle to spray urea according to the urea injection amount. The urea supplementation parameters include but are not limited to the original exhaust NOx value, exhaust temperature and SCR airspeed; according to the original exhaust NOx value, exhaust temperature value T and SCR airspeed, the urea injection amount is determined in the ammonia storage closed loop MAP, and then the urea nozzle is closed-loop controlled to spray urea.

[0098] In the solution provided in the embodiment of the present application, the intelligent control valve in the hydrogen internal combustion engine aftertreatment device is respectively connected to the exhaust inlet, the H 2 The input end of the SCR is connected to the input end of the first pipeline, and the output end of the first pipeline is connected to the SCR. 2 The output end of SCR is connected to SCR through the second pipeline; the intelligent control valve is used to control H 2 The conduction state between the input end of the SCR and the input end of the first pipeline and the exhaust inlet; when the exhaust temperature of the hydrogen internal combustion engine aftertreatment device is lower than the first preset temperature, the intelligent control valve controls the H 2 The input end of the SCR is connected to the exhaust inlet, and the input end of the first pipe is not connected to the exhaust inlet. When the temperature is low, use H 2 SCR converts NOx in the exhaust gas, solves the problem of low NOx conversion rate caused by low-temperature urea crystallization, and improves the NOx conversion rate in the exhaust gas at low temperatures; when the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls H 2 The input end of the SCR is not connected to the exhaust inlet, and the input end of the first pipe is connected to the exhaust inlet, so that when the temperature is high, the SCR is used to convert the NOx in the exhaust. At different temperatures, different NOx conversion methods are used to improve the NOx conversion rate and reduce the NOx emissions of automobile exhaust.

[0099] Reference Figure 7, is another flow chart of the control method of the hydrogen internal combustion engine post-treatment device provided in the embodiment of the present application, and is specifically described as follows:

[0100] Collect the working status information of the hydrogen internal combustion engine aftertreatment device. The relevant description of the working status information is as described above and will not be repeated here. Based on the exhaust temperature in the working status information, it is determined whether the exhaust temperature is less than or equal to the second preset temperature. When the exhaust temperature is less than or equal to the second preset temperature, the intelligent control valve controls the exhaust inlet and the H 2 The SCR is turned on, the exhaust inlet is disconnected from the first pipe, and the exhaust passes through the H 2 After SCR treatment, it flows to SCR; 2 During the SCR treatment of NOx in the exhaust gas, it is determined whether the tail exhaust NOx value is less than the NOx limit value; when the tail exhaust NOx value is less than the NOx limit value, the hydrogen injector is controlled to inject hydrogen. The process of determining the amount of hydrogen injected by the hydrogen injector refers to the above content and will not be repeated here.

[0101] When the exhaust temperature is greater than the second preset temperature, it is determined whether the exhaust temperature is greater than or equal to the first preset temperature. When the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls the exhaust inlet and H 2 The SCR is turned on, the exhaust inlet is disconnected from the first pipe, and the exhaust passes through the H 2 After SCR treatment, it flows to SCR and controls the heat dissipation device to 2 SCR heat dissipation. Control the heat dissipation device to H 2 The process of SCR heat dissipation is as follows: 2 If the temperature of the SCR is lower than the second preset temperature, 2 When the temperature of the SCR is not less than the second preset temperature, the temperature regulating grille of the heat dissipation device is controlled to be fully opened; when H 2 When the temperature of the SCR is lower than the second preset temperature, it is determined that H 2 Whether the temperature of the SCR is less than or equal to the third preset temperature, and whether the tail exhaust NOx value is less than the NOx limit value; when H 2 When the temperature of the SCR is less than or equal to the third preset temperature, the temperature regulating grille is controlled to be fully closed; when the H 2 When the temperature of the SCR is greater than the third preset temperature, the thermostatic grille is controlled to be opened; further, when it is determined that the tail NOx value is less than the NOx limit, the hydrogen injector is controlled to inject hydrogen; when it is determined that the tail NOx value is not less than the NOx limit, it is determined that hydrogen does not need to be supplemented. Preferably, the third preset temperature is less than the second preset temperature.

[0102] Furthermore, the control method provided by the present application is carried out in real time, so that the strategy applied to the conversion of NOx in the exhaust gas can be adjusted in time. 2A post-treatment device and control method combining the advantages of two NOx treatment methods: SCR high NOx conversion efficiency and SCR ultra-high NOx conversion efficiency at medium and high temperatures, and combining H 2 The SCR temperature control part maximizes the ability to treat NOx emissions from hydrogen internal combustion engine after-treatment exhaust gas, and can eliminate the risk of urea crystallization in SCR at low temperatures, achieving efficient NOx emission reduction in hydrogen internal combustion engine exhaust gas within a wide exhaust temperature range, solving the NOx emission problem of hydrogen internal combustion engines, with a simple structure and strong practicality.

[0103] The hydrogen internal combustion engine aftertreatment device provided in the present application can be combined with low temperature H 2 The high NOx conversion efficiency of SCR and the high-efficiency NOx conversion zone of SCR at medium and high temperatures eliminate the risk of urea crystallization of SCR at low temperatures, achieve efficient reduction of NOx emissions from hydrogen internal combustion engine exhaust gas within a wide exhaust temperature range, solve the NOx emission problem of hydrogen internal combustion engines, have a simple structure and strong practicality; further, the hydrogen internal combustion engine after-treatment device can be applied to the engine to reduce the NOx content in the exhaust gas emitted by the engine.

[0104] It should be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

[0105] The specific implementation processes and derivative methods of the above-mentioned embodiments are all within the protection scope of the present invention.

[0106] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without creative work.

[0107] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0108] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydrogen internal combustion engine post-treatment device, characterized in that: include: A heat dissipation device, a selective catalytic reduction device SCR using NH3 as a reducing agent, and a selective hydrogen catalytic reduction catalyst H2SCR using H2 as a reducing agent; The input end of the SCR is connected to the output end of the first pipeline and the output end of the second pipeline respectively; The output end of the H2SCR is connected to the input end of the second pipeline; The input end of the H2SCR and the input end of the first pipeline are both connected to the intelligent control valve; The intelligent control valve is used to control the conduction state between the input end of the H2SCR and the input end of the first pipeline and the exhaust inlet; The heat dissipation device is used to dissipate heat from the H2SCR.

2. The hydrogen internal combustion engine aftertreatment device according to claim 1, characterized in that: The H2SCR is provided with heat dissipation fins.

3. The hydrogen internal combustion engine aftertreatment device according to claim 1, characterized in that: The heat dissipation device comprises: Wind regulator; The wind force regulator is used to adjust the wind flow rate of the heat dissipation device blowing toward the H2SCR.

4. A method for controlling a post-treatment device of a hydrogen internal combustion engine, characterized in that: Applied to the hydrogen internal combustion engine aftertreatment device according to any one of claims 1 to 3, the method comprises: Collecting working status information of the hydrogen internal combustion engine post-processing device in real time; When the exhaust temperature in the working state information is less than a first preset temperature, the exhaust gas to be treated is controlled to first flow through a selective hydrogen catalytic reduction catalyst H2SCR using H2 as a reducing agent in the hydrogen internal combustion engine aftertreatment device, and then flow through a selective catalytic reduction SCR using NH3 as a reducing agent in the hydrogen internal combustion engine aftertreatment device, and a preset low-temperature exhaust treatment strategy is used to use the H2SCR and the SCR to treat NOx in the exhaust gas; When the exhaust temperature in the working status information is greater than or equal to a first preset temperature, the exhaust gas to be treated is controlled not to flow through the H2SCR but to flow directly through the SCR, and a preset high-temperature exhaust treatment strategy is used to control a preset urea nozzle to inject urea, and the SCR is used to treat NOx in the exhaust gas.

5. The method according to claim 4, characterized in that The method of using a preset low-temperature exhaust gas treatment strategy and using the H2SCR and the SCR to treat NOx in the exhaust gas includes: Determining whether the exhaust temperature in the working state information is less than or equal to a second preset temperature in the low-temperature exhaust treatment strategy; When the exhaust temperature in the working state information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, determining whether the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value in the low-temperature exhaust treatment strategy; When the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value, the H2SCR is used to reduce the NOx in the exhaust gas, and the SCR is used to treat the NOx in the exhaust gas treated by the H2SCR; When the tail exhaust NOx value in the working status information is greater than the NOx limit value, hydrogen is added to the exhaust before the exhaust to be treated flows to the H2SCR, the H2SCR is used to treat the NOx in the exhaust after hydrogen is added, and the SCR is used to treat the NOx in the exhaust after being treated by the H2SCR.

6. The method according to claim 5, characterized in that The method of supplementing the exhaust gas with hydrogen comprises: Obtain hydrogen replenishment parameters; The hydrogen replenishment parameter is used to determine a hydrogen replenishment value, and the injection amount of hydrogen injected into the exhaust gas by a preset hydrogen injector is controlled according to the hydrogen replenishment value.

7. The method according to claim 5, characterized in that Also includes: When the exhaust temperature in the working status information is greater than the second preset temperature in the low-temperature exhaust treatment strategy, based on the preset heat dissipation strategy, the heat dissipation device in the hydrogen internal combustion engine aftertreatment device is controlled to perform heat dissipation treatment on the H2SCR, and the exhaust is treated by the H2SCR before the SCR is used to treat the exhaust.

8. The method according to claim 7, characterized in that The method of controlling the heat dissipation device in the hydrogen internal combustion engine aftertreatment device to perform heat dissipation treatment on the H2SCR based on a preset heat dissipation strategy includes: The opening of the wind regulator in the heat dissipation device is controlled to be 100%, so that the gas used for heat dissipation passes through the wind regulator to dissipate heat for the H2SCR, and the opening of the wind regulator is adjusted according to the temperature change of the H2SCR.

9. The method according to claim 4, characterized in that The controlling the preset urea nozzle to spray urea comprises: Get urea supplement parameters; The urea replenishment parameter is used to determine a urea injection amount, and the urea nozzle is controlled to inject urea according to the urea injection amount.

10. An engine, characterized in that: A hydrogen internal combustion engine aftertreatment device comprising any one of claims 1 to 3.

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