Hydrogen internal combustion engine nitrogen oxide emission device and vehicle

Abstract

The application discloses a hydrogen internal combustion engine nitrogen oxide emission device and a vehicle, and relates to the technical field of vehicle engines, and in particular to a hydrogen internal combustion engine nitrogen oxide emission device and a vehicle. The device comprises a tail gas heating vaporization circuit, a cooling water heating vaporization circuit, a tail gas treatment circuit and a post-treatment controller. The tail gas heating vaporization circuit comprises a hydrogen internal combustion engine, a first vaporizer and a hydrogen distribution proportional valve. The post-treatment controller is electrically connected with an electric control unit of the hydrogen internal combustion engine, and the post-treatment controller is electrically connected with the hydrogen distribution proportional valve. The tail gas output port of the hydrogen internal combustion engine is communicated with the input end of the tail gas treatment circuit through the first vaporizer. The input end of the hydrogen distribution proportional valve is externally connected with a liquid hydrogen tank. The first output end of the hydrogen distribution proportional valve is communicated with the liquid hydrogen input port of the first vaporizer. The hydrogen gas output port of the first vaporizer is communicated with the hydrogen gas input port of the hydrogen internal combustion engine. The second output end of the hydrogen distribution proportional valve is communicated with the liquid hydrogen input port of the cooling water heating vaporization circuit. The device effectively improves the economy of the vehicle engine.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle exhaust aftertreatment, in particular to a hydrogen internal combustion engine nitrogen oxide emission device and vehicle. BACKGROUND

[0002] Hydrogen fuel engine as a clean energy technology, its emissions are relatively less, but still exist. The main pollutants of hydrogen fuel engine is nitrogen oxides (NOx), because in the hydrogen fuel combustion process, due to high temperature conditions, may produce a certain amount of nitrogen oxides, including nitrogen monoxide (NO) and nitrogen dioxide (NO2).

[0003] Hydrogen internal combustion engine uses liquid hydrogen storage, in practical application need to carry on vaporization first, then injection combustion. General hydrogen vaporizer uses engine cooling water heating vaporization, but this scheme exists engine cold water is not enough, especially in engine cold start, cooling water temperature is low, liquid hydrogen vaporization is insufficient, there is gas-liquid mixing phenomenon influence combustion. Liquid hydrogen vaporization large amount of heat absorption, also can cause engine cooling water temperature drop sharply, affect engine economy. SUMMARY

[0004] The embodiment of the present application provides a hydrogen internal combustion engine nitrogen oxide emission device and vehicle, the device uses exhaust heating vaporization circuit and / or cooling water heating vaporization circuit to vaporize liquid hydrogen, solves the problem of insufficient liquid hydrogen vaporization when engine cooling water is used to heat and vaporize liquid hydrogen, avoids the problem of liquid hydrogen vaporization large amount of heat absorption leading to engine cooling water temperature drop sharply, and further improves the engine economy of the vehicle, greatly improves the user experience.

[0005] In a first aspect, the present application provides the following technical solutions through an embodiment of the present application:

[0006] The hydrogen internal combustion engine nitrogen oxide emission device comprises: an exhaust gas heating vaporization circuit, a cooling water heating vaporization circuit, an exhaust gas treatment circuit and a post-processing controller, the exhaust gas heating vaporization circuit comprises a hydrogen internal combustion engine, a first vaporizer and a hydrogen distribution proportional valve, the post-processing controller is electrically connected with an electric control unit of the hydrogen internal combustion engine, and the post-processing controller is electrically connected with the hydrogen distribution proportional valve; an exhaust gas output port of the hydrogen internal combustion engine is communicated with an input end of the exhaust gas treatment circuit through the first vaporizer, and is used for transmitting the residual heat of the exhaust gas to the first vaporizer; an input end of the hydrogen distribution proportional valve is circumscribed with a liquid hydrogen tank, a first output end of the hydrogen distribution proportional valve is communicated with a liquid hydrogen input port of the first vaporizer, a hydrogen gas output port of the first vaporizer is communicated with a hydrogen gas input port of the hydrogen internal combustion engine, and is used for flowing the liquid hydrogen flowing into the first vaporizer into the hydrogen internal combustion engine after heating and vaporization, and a second output end of the hydrogen distribution proportional valve is communicated with a liquid hydrogen input port of the cooling water heating vaporization circuit, and is used for flowing the liquid hydrogen flowing into the cooling water heating vaporization circuit into the hydrogen internal combustion engine after heating and vaporization.

[0007] Preferably, the cooling water heating vaporization circuit comprises the hydrogen internal combustion engine, a second vaporizer and a cooling water control valve, the post-processing controller is electrically connected with the cooling water control valve; a cooling water output port of the hydrogen internal combustion engine flows back to the hydrogen internal combustion engine through the cooling water control valve and the second vaporizer, and is used for transmitting heat to the second vaporizer; the second output end of the hydrogen distribution proportional valve is communicated with a liquid hydrogen input port of the second vaporizer, and a hydrogen gas output port of the second vaporizer is communicated with the hydrogen gas input port of the hydrogen internal combustion engine, and is used for heating and vaporizing the liquid hydrogen flowing into the second vaporizer, and the hydrogen gas obtained through vaporization flows to the hydrogen internal combustion engine.

[0008] Preferably, the exhaust gas heating vaporization circuit further comprises a temperature detector which is electrically connected with the post-processing controller, and is located between the first vaporizer and the input end of the exhaust gas treatment circuit, and is used for monitoring the temperature of the exhaust gas flowing into the exhaust gas treatment circuit.

[0009] The exhaust gas treatment circuit comprises a catalyst reducer in which a reduction catalyst is arranged, and the first vaporizer is communicated with an input end of the catalyst reducer.

[0010] Preferably, the reduction catalyst is an H2-SCR catalyst.

[0011] Preferably, the exhaust gas treatment circuit further comprises a first nitrogen oxide sensor which is electrically connected with the post-processing controller, and is arranged at an output end of the reduction catalyst, and is used for monitoring the nitrogen oxide concentration of the exhaust gas processed through the reduction catalyst.

[0012] Preferably, the tail gas heating vaporization circuit further comprises a post-processing hydrogen nozzle, electrically connected with the post-processing controller, and arranged between the tail gas output end of the hydrogen internal combustion engine and the tail gas input port of the first vaporizer.

[0013] Preferably, the post-processing hydrogen nozzle is further in communication with the hydrogen output port of the first vaporizer.

[0014] Preferably, the tail gas heating vaporization circuit further comprises a second nitrogen oxide sensor, electrically connected with the post-processing controller, and arranged between the tail gas output end of the hydrogen internal combustion engine and the tail gas input port of the first vaporizer, for monitoring the nitrogen oxide concentration of the tail gas.

[0015] In a second aspect, the present application provides the following technical solutions through an embodiment of the present application:

[0016] A vehicle comprising a vehicle body and the hydrogen internal combustion engine nitrogen oxide emission device according to any one of the first aspect.

[0017] The one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0018] The hydrogen internal combustion engine nitrogen oxide emission device provided by the embodiments of the present application is provided with a tail gas heating vaporization circuit and a cooling water heating vaporization circuit, the tail gas output end of the hydrogen internal combustion engine is in communication with the input end of the tail gas treatment circuit through the first vaporizer, for transferring the waste heat of the tail gas to the first vaporizer, meanwhile, the tail gas heating vaporization circuit comprises the hydrogen internal combustion engine, the first vaporizer and a hydrogen distribution proportional valve, the hydrogen distribution proportional valve is used for heating and vaporizing the liquid hydrogen flowing into the first vaporizer and then flowing into the hydrogen internal combustion engine, and is used for heating and vaporizing the liquid hydrogen flowing into the cooling water heating vaporization circuit and then flowing into the hydrogen internal combustion engine, so that when the engine cooling water temperature is detected to be low, the first vaporizer can be used for vaporization work, the liquid hydrogen vaporization effect of the tail gas is better, and the tail gas temperature is reduced, which can effectively solve the problem of insufficient liquid hydrogen vaporization when the engine cooling water heats and vaporizes the liquid hydrogen, and avoid the situation that the liquid hydrogen vaporization absorbs a large amount of heat to cause the engine cooling water temperature to drop sharply, the device can improve the engine economy of the vehicle and improve the user experience. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort.

[0020] Figure 1 A schematic diagram of a hydrogen internal combustion engine nitrogen oxide emission device in an embodiment of the present application;

[0021] Figure 2 A schematic diagram of a relationship curve in an embodiment of the present application;

[0022] Figure 3 A comparative schematic diagram of a relationship curve in an embodiment of the present application;

[0023] Figure 4 A schematic diagram of a structure of a vehicle in an embodiment of the present application.

[0024] Reference signs:

[0025] H2-SCR catalyst 101, aftertreatment controller 102, hydrogen internal combustion engine 103, temperature detector 104, first vaporizer 105, hydrogen distribution proportional valve 106, second vaporizer 107, cooling water control valve 108, aftertreatment hydrogen nozzle 109, first nitrogen oxide sensor 110, first nitrogen oxide sensor 111, liquid hydrogen tank 112. DETAILED DESCRIPTION

[0026] The inventor has found through research that in the prior art, liquid hydrogen is vaporized by engine cooling water heating, and there is a problem of insufficient engine cooling water, especially when the engine is cold started, the cooling water temperature is low, the liquid hydrogen vaporization is insufficient, and there is a gas-liquid mixing phenomenon affecting combustion. Liquid hydrogen vaporization absorbs a large amount of heat, which also causes the engine cooling water temperature to drop sharply, affecting engine economy.

[0027] Therefore, the present application provides a hydrogen internal combustion engine nitrogen oxide emission device and a vehicle, which adopts an exhaust gas heating vaporization circuit and / or a cooling water heating vaporization circuit to vaporize liquid hydrogen, solves the problem of insufficient liquid hydrogen vaporization when the engine cooling water is used to heat and vaporize liquid hydrogen, avoids the problem of a large amount of heat absorption by liquid hydrogen vaporization causing the engine cooling water temperature to drop sharply, and thus improves the engine economy of the vehicle and greatly improves the user experience.

[0028] The technical solution of the present application embodiment is to solve the above technical problems, and the general idea is as follows:

[0029] The application discloses a hydrogen internal combustion engine nitrogen oxide emission device, which comprises an exhaust gas heating vaporization loop, a cooling water heating vaporization loop, an exhaust gas treatment loop and a post-processing controller, wherein the exhaust gas heating vaporization loop comprises a hydrogen internal combustion engine, a first vaporizer and a hydrogen distribution proportional valve; the post-processing controller is electrically connected with an electric control unit of the hydrogen internal combustion engine; the post-processing controller is electrically connected with the hydrogen distribution proportional valve; an exhaust gas output port of the hydrogen internal combustion engine is communicated with an input end of the exhaust gas treatment loop through the first vaporizer, and is used for transferring the waste heat of the exhaust gas to the first vaporizer; an input end of the hydrogen distribution proportional valve is connected with a liquid hydrogen tank; a first output end of the hydrogen distribution proportional valve is communicated with a liquid hydrogen input port of the first vaporizer; a hydrogen gas output port of the first vaporizer is communicated with a hydrogen gas input port of the hydrogen internal combustion engine, and is used for flowing the liquid hydrogen into the hydrogen internal combustion engine after the liquid hydrogen flowing into the first vaporizer is heated and vaporized; and a second output end of the hydrogen distribution proportional valve is communicated with a liquid hydrogen input port of the cooling water heating vaporization loop, and is used for flowing the liquid hydrogen into the hydrogen internal combustion engine after the liquid hydrogen flowing into the cooling water heating vaporization loop is heated and vaporized.

[0030] In order to better understand the above technical solutions, the above technical solutions will be described in detail below in combination with the accompanying drawings and specific embodiments.

[0031] In a first aspect, the hydrogen internal combustion engine nitrogen oxide emission device provided by the embodiment of the application comprises an exhaust gas heating vaporization loop, a cooling water heating vaporization loop, an exhaust gas treatment loop and a post-processing controller 102, wherein the exhaust gas heating vaporization loop comprises a first vaporizer 105 and a hydrogen distribution proportional valve 106; the post-processing controller 102 is electrically connected with an electric control unit of a hydrogen internal combustion engine 103; and the post-processing controller 102 is electrically connected with a control end of the hydrogen distribution proportional valve 106. Figure 1

[0032] The exhaust gas output port of the hydrogen internal combustion engine 103 is communicated with the input end of the exhaust gas treatment loop through the first vaporizer 105, and is used for transferring the waste heat of the exhaust gas to the first vaporizer 105; the input end of the hydrogen distribution proportional valve 106 is connected with a liquid hydrogen tank 112; the first output end of the hydrogen distribution proportional valve 106 is communicated with the liquid hydrogen input port of the first vaporizer 105 through a liquid hydrogen pipe; the hydrogen gas output port of the first vaporizer 105 is communicated with the hydrogen gas input port of the hydrogen internal combustion engine 103 through a gaseous hydrogen pipe, and is used for flowing the liquid hydrogen into the hydrogen internal combustion engine 103 after the liquid hydrogen flowing into the first vaporizer 105 is heated and vaporized; and the second output end of the hydrogen distribution proportional valve 106 is communicated with the liquid hydrogen input port of the cooling water heating vaporization loop through a liquid hydrogen pipe, and is used for flowing the liquid hydrogen into the hydrogen internal combustion engine 103 after the liquid hydrogen flowing into the cooling water heating vaporization loop is heated and vaporized.

[0033] ​In the present application, the post-processing controller 102 is electrically connected with the electric control unit of the hydrogen internal combustion engine 103, and the post-processing controller 102 is configured to acquire the temperature of the cooling water of the hydrogen internal combustion engine 103 in real time. When the engine is cold started, the temperature of the cooling water is lower than the first preset temperature c ℃, which can be between 70-100 ℃, and the specific value can be determined according to the influence on the cold start of the engine. Then, the post-processing controller 102 disconnects the cooling water heating vaporization circuit and connects the exhaust gas heating vaporization circuit.

[0034] In a specific embodiment, the cooling water heating vaporization circuit can include a second vaporizer 107 and a cooling water control valve 108, and the post-processing controller 102 is electrically connected with the control end of the cooling water control valve 108. The cooling water outlet of the hydrogen internal combustion engine 103 is connected with the cooling water control valve 108 and the second vaporizer 107 through cooling management, and then flows back to the hydrogen internal combustion engine 103, so as to transfer heat to the second vaporizer 107. The second output end of the hydrogen distribution proportional valve 106 is connected with the liquid hydrogen input end of the second vaporizer 107 through a liquid hydrogen pipe, and the hydrogen gas output end of the second vaporizer 107 is connected with the hydrogen gas input end of the hydrogen internal combustion engine 103 through a gaseous hydrogen pipe, so as to heat and vaporize the liquid hydrogen flowing into the second vaporizer 107, and the hydrogen gas obtained by vaporization flows to the hydrogen internal combustion engine 103.

[0035] As another optional embodiment, the cooling water heating vaporization circuit can further include a temperature sensor (not shown in the figure) electrically connected with the post-processing controller 102, and the temperature sensor is arranged between the cooling water outlet of the first vaporizer 105 and the hydrogen internal combustion engine 103, so as to detect the temperature of the cooling water output from the first vaporizer 105.

[0036] In a specific embodiment, the exhaust gas heating vaporization circuit can further include a temperature detector 104 electrically connected with the post-processing controller 102, and the temperature detector 104 is arranged between the first vaporizer 105 and the input end of the exhaust gas treatment circuit, so as to monitor the temperature of the exhaust gas flowing into the exhaust gas treatment circuit.

[0037] It should be noted that the temperature detector 104 is electrically connected with the post-processing controller 102, and is configured to monitor the temperature of the exhaust gas flowing into the exhaust gas treatment circuit. Optionally, the temperature detector 104 can be a temperature sensor, a temperature detector, etc.

[0038] In the specific implementation process, the exhaust gas treatment circuit includes a catalyst reducer provided with a reduction catalyst, and the catalyst reducer is connected with the output end of the exhaust gas heating vaporization circuit.

[0039] In practical applications, when the 112 hydrogen internal combustion engine is cold started, the cooling water temperature of the 112 hydrogen internal combustion engine is obtained; if the 112 cooling water temperature is lower than the first preset temperature, the 112 cooling water heating vaporization circuit is controlled to be disconnected from the cooling water pipeline of the hydrogen internal combustion engine, and the liquid hydrogen in the external liquid hydrogen tank is controlled to enter the 112 exhaust gas heating vaporization circuit, and vaporization occurs in the 112 exhaust gas heating vaporization circuit to reduce the exhaust gas temperature in the 112 exhaust gas heating vaporization circuit; if the 112 cooling water temperature reaches the first preset temperature, the temperature of the exhaust gas output by the 112 exhaust gas heating vaporization circuit is obtained; according to the temperature of the exhaust gas output by the 112 exhaust gas heating vaporization circuit, the 112 cooling water heating vaporization circuit is controlled to be disconnected or connected with the cooling water pipeline of the hydrogen internal combustion engine, and the liquid hydrogen in the external liquid hydrogen tank is controlled to enter the 112 exhaust gas heating vaporization circuit and / or the 112 cooling water heating vaporization circuit.

[0040] In specific embodiments, according to the temperature of the exhaust gas output by the 112 exhaust gas heating vaporization circuit, the 112 cooling water heating vaporization circuit is controlled to be disconnected or connected with the cooling water pipeline of the hydrogen internal combustion engine, and the liquid hydrogen in the external liquid hydrogen tank is controlled to enter the 112 exhaust gas heating vaporization circuit and / or the 112 cooling water heating vaporization circuit, which can include: obtaining a first switching temperature and a second switching temperature of the reduction catalyst, wherein the first switching temperature and the second switching temperature are determined based on the conversion efficiency and temperature relationship curve of the reduction catalyst, and the first switching temperature is less than the second switching temperature; based on the first switching temperature, the second switching temperature and the preset concentration value, the first target temperature and the second target temperature are determined, wherein the first target temperature is less than or equal to the first switching temperature, and the second target temperature is greater than or equal to the second switching temperature; based on the first switching temperature, the second switching temperature, the first target temperature, the second target temperature and the exhaust gas temperature, the cooling water heating vaporization circuit is controlled to be disconnected or connected with the cooling water pipeline of the hydrogen internal combustion engine 103, and the liquid hydrogen in the external liquid hydrogen tank 112 is controlled to enter the exhaust gas heating vaporization circuit and / or the cooling water heating vaporization circuit.

[0041] Preferably, the reduction catalyst in the present application can be an H2-SCR catalyst 101. As shown in Figure 1 The exhaust gas treatment circuit can include an H2-SCR catalyst 101 (hydrogen selective catalytic reduction catalyst), which is in communication with the output end of the exhaust gas heating vaporization circuit.

[0042] In one embodiment, obtaining the first switching temperature and the second switching temperature of the H2-SCR catalyst 101 may include: obtaining a curve showing the relationship between the conversion efficiency of the H2-SCR catalyst 101 and temperature, wherein the curve is obtained by conducting a temperature verification experiment on the H2-SCR catalyst 101, and the horizontal axis of the curve represents temperature and the vertical axis represents conversion efficiency; determining the low-temperature nitrogen oxide conversion efficiency inflection point and the high-temperature nitrogen oxide conversion efficiency inflection point of the H2-SCR catalyst 101 based on the curve; determining the first switching temperature based on the low-temperature nitrogen oxide conversion efficiency inflection point, and determining the second switching temperature based on the high-temperature nitrogen oxide conversion efficiency inflection point.

[0043] like Figure 2 The diagram shows a schematic of the relationship curve. By using the common operating conditions of internal combustion engines, temperature verification tests were conducted to obtain the relationship curve between conversion efficiency and temperature. Then, the inflection points of low-temperature NOx conversion efficiency and high-temperature NOx conversion efficiency were selected. The inflection point of low-temperature NOx conversion efficiency can be the first point where the slope of the curve changes, and the inflection point of high-temperature NOx conversion efficiency can be the second point where the slope of the curve changes. The inflection point of low-temperature NOx conversion efficiency is taken as the first switching temperature a0, and the inflection point of high-temperature NOx conversion efficiency is taken as the second switching temperature b0.

[0044] The H2-SCR catalyst 101 used in this application, compared to catalysts used in traditional technologies (such as NH3-SCR), has advantages. NH3-SCR suffers from several drawbacks: below 180°C, the reducing agent urea aqueous solution cannot be fully hydrolyzed to produce NH3 gas, and urea crystals are easily formed. Furthermore, the catalyst conversion efficiency is low at low temperatures. In contrast, the H2-SCR catalyst 101 can achieve a certain conversion efficiency even at lower temperatures. Figure 3 As shown, the H2-SCR catalyst 101 can avoid the relatively low conversion efficiency at lower temperatures (≤X℃, where X is between 0-150℃), i.e. Figure 3 The comparison of the relationship curves for the two catalysts is shown.

[0045] In the present application, based on the first switching temperature, the second switching temperature and the preset concentration value, the first target temperature and the second target temperature are determined, which can include: based on the first switching temperature and the second switching temperature, performing the following temperature correction step: reducing the first switching temperature by a preset step size, and increasing the second switching temperature by a preset step size, to obtain the adjusted first switching temperature and the second switching temperature; judging whether the H2-SCR catalyst 101 based on the adjusted first switching temperature and the second switching temperature meets the preset concentration value of the exhaust gas emission concentration at the output end of the catalyst reducer after the exhaust gas is treated, if not, based on the adjusted first switching temperature and the second switching temperature, the temperature correction step is repeatedly executed until the exhaust gas emission concentration at the output end of the catalyst reducer is within the preset concentration value. Wherein, the preset concentration value is determined according to the regulatory emission limit value, and optionally, the preset step size can be between 1-3℃.

[0046] Specifically, as shown in Figure 2 The first switching temperature is reduced by a preset step size, and the second switching temperature is increased by a preset step size, to obtain the low-temperature switching temperature a value and the high-temperature switching temperature b of the H2-SCR efficiency, and the original a0℃-b0℃ interval is increased, so that the effective processing interval of the H2-SCR catalyst 101 is increased, and the exhaust gas Nox better meets the regulatory emission limit value requirement.

[0047] It should be noted that H2-SCR has high conversion efficiency in the low-temperature region of 100-300℃, but in the high-temperature section, the reaction activity under the condition of oxygen enrichment is relatively low, and the competition reaction of hydrogen and oxygen inhibits the effect of selective catalytic reduction of nitrogen oxides by hydrogen, so that the effect of H2-SCR is not as expected. The exhaust gas temperature of the hydrogen internal combustion engine is higher than 300℃ under medium and high load, so that the H2-SCR cannot meet the application requirements of the hydrogen internal combustion engine under all working conditions. In order to solve this problem, the present application adopts the method of controlling the cooling water heating vaporization circuit and the cooling water pipeline of the hydrogen internal combustion engine 103 to be disconnected or connected based on the first switching temperature, the second switching temperature, the first target temperature, the second target temperature and the exhaust gas temperature, and controlling the liquid hydrogen in the external liquid hydrogen tank 112 to enter the exhaust gas heating vaporization circuit and / or the cooling water heating vaporization circuit, so that the exhaust gas temperature input into the H2-SCR catalyst 101 can be kept in a high-efficiency interval.

[0048] In specific embodiments, the control of the cooling water heating vaporization loop and the cooling water pipeline of the hydrogen internal combustion engine 103 to be disconnected or connected based on the first switching temperature, the second switching temperature, the first target temperature, the second target temperature and the tail gas temperature, and the control of the liquid hydrogen in the external liquid hydrogen tank 112 to enter the tail gas heating vaporization loop and / or the cooling water heating vaporization loop, can include: if the tail gas temperature is lower than the first target temperature a ℃ or between the first target temperature a ℃ and the first switching temperature a0 ℃, the cooling water heating vaporization loop and the cooling water pipeline of the hydrogen internal combustion engine 103 are controlled to be connected, and the liquid hydrogen in the external liquid hydrogen tank 112 is controlled to enter the cooling water heating vaporization loop, so that the liquid hydrogen input into the loop is vaporized based on the hydrogen internal combustion engine 103 cooling water, and the tail gas heating vaporization loop is directly used for transmitting the tail gas of the hydrogen internal combustion engine 103; if the tail gas temperature is between the first switching temperature a0 ℃ and the second switching temperature b0 ℃, the cooling water heating vaporization loop and the cooling water pipeline of the hydrogen internal combustion engine 103 are controlled to be disconnected or connected, and the liquid hydrogen in the external liquid hydrogen tank 112 is controlled to enter the tail gas heating vaporization loop and the cooling water heating vaporization loop; if the tail gas temperature is greater than the second target temperature b ℃, the cooling water heating vaporization loop and the cooling water pipeline of the hydrogen internal combustion engine 103 are controlled to be disconnected, and the liquid hydrogen in the external liquid hydrogen tank 112 is controlled to enter the tail gas heating vaporization loop.

[0049] In specific embodiments, the control of the liquid hydrogen in the external liquid hydrogen tank 112 to enter the tail gas heating vaporization loop can include: controlling the first output end of the hydrogen distribution proportional valve 106 to be closed, so that the liquid hydrogen in the external liquid hydrogen tank 112 enters the first vaporizer 105 from the hydrogen distribution proportional valve 106.

[0050] Specifically, the control of the cooling water heating vaporization loop and the cooling water pipeline of the hydrogen internal combustion engine 103 to be disconnected or connected can include: controlling the cooling water control valve 108 to be disconnected or connected; the control of the liquid hydrogen in the external liquid hydrogen tank 112 to enter the cooling water heating vaporization loop includes: controlling the second output end of the hydrogen distribution proportional valve 106 to be closed, so that the liquid hydrogen in the external liquid hydrogen tank 112 enters the second vaporizer 107 from the hydrogen distribution proportional valve 106.

[0051] Further, in order to realize more flexible adjustment of the exhaust NOX concentration, the tail gas heating vaporization loop can further include a post-processing hydrogen nozzle 109 electrically connected with the post-processing controller 102, the post-processing hydrogen nozzle 109 is arranged between the hydrogen internal combustion engine 103 and the tail gas input port of the first vaporizer 105, the post-processing hydrogen nozzle 109 is in communication with the hydrogen gas output port of the first vaporizer 105, after obtaining the first switching temperature, the second switching temperature, the first target temperature, the second target temperature and the tail gas temperature, the method can further include:

[0052] If the exhaust gas temperature is lower than the first target temperature a℃, the post-processing hydrogen gas nozzle 109 is closed; if the exhaust gas temperature is between the first target temperature a℃ and the first switching temperature a0℃, the post-processing hydrogen gas nozzle 109 is opened; if the exhaust gas temperature is between the first switching temperature a0℃ and the second switching temperature b0℃, the post-processing hydrogen gas nozzle 109 is opened; if the exhaust gas temperature is greater than the second target temperature b℃, the post-processing hydrogen gas nozzle 109 is opened.

[0053] The post-processing hydrogen gas nozzle 109 is used to reduce nitrogen oxides (NOx) in the exhaust gas by spraying hydrogen, thereby reducing NOx emissions.

[0054] Further, the post-processing hydrogen gas nozzle 109 also communicates with the hydrogen output end of the second vaporizer 107, so that part of the hydrogen in the second vaporizer 107 flows into the exhaust gas heating and vaporization circuit through the post-processing hydrogen gas nozzle 109, thereby increasing the hydrogen injection amount.

[0055] Further, in order to obtain the NOX concentration of the exhaust gas, the exhaust gas treatment circuit can further include a first nitrogen oxide sensor 110 (i.e., a post-NOX sensor) arranged at the output end of the H2-SCR catalyst 101, and the first nitrogen oxide sensor 110 is electrically connected to the post-processing controller 102. The method further includes: obtaining the nitrogen oxide concentration detected by the first nitrogen oxide sensor 110 (i.e., the output of the catalyst reducer); and increasing the injection amount of the post-processing hydrogen gas nozzle 109 if the nitrogen oxide concentration is greater than a preset concentration value. This allows the post-processing hydrogen gas nozzle 109 to dynamically adjust the hydrogen injection amount according to different combustion conditions, thereby optimizing the NOx emission reduction effect.

[0056] In a specific embodiment, the exhaust gas heating and vaporization circuit can further include a second nitrogen oxide sensor 111 (i.e., a pre-NOX sensor) electrically connected to the post-processing controller 102, and the second nitrogen oxide sensor 111 is arranged between the exhaust gas output end of the hydrogen internal combustion engine 103 and the exhaust gas input port of the first vaporizer 105, and is used to monitor the nitrogen oxide concentration of the exhaust gas.

[0057] In one embodiment, the injection amount of the post-processing hydrogen gas nozzle 109 is first determined based on the nitrogen oxide concentrations detected by the pre-NOX sensor and the post-NOX sensor, and then the injection amount of the post-processing hydrogen gas nozzle 109 is corrected based on the nitrogen oxide concentration of the exhaust gas detected by the post-NOX sensor, so that the NOX of the exhaust gas is always within a preset concentration value.

[0058] Specifically, when the engine is cold started, if the cooling water temperature is lower than the first preset temperature c ℃, the cooling water control valve 108 is controlled to be closed, so that the cooling water pipeline to the second vaporizer 107 is closed, the first output end of the hydrogen distribution proportional valve 106 is controlled to be closed, so that the liquid hydrogen passes through the hydrogen distribution proportional valve 106 and enters the first vaporizer 105, the liquid hydrogen is heated and vaporized in the first vaporizer 105 by the exhaust gas of the hydrogen internal combustion engine 103, and the vaporized hydrogen flows into the hydrogen internal combustion engine 103, so that the second vaporizer 107 replaces the working of the first vaporizer 105, which can reduce the heat loss of the engine cooling water when the first vaporizer 105 works, avoid the heat absorption of the engine cooling water, cause the engine cooling water temperature to rise slowly, and affect the engine starting and lubrication performance. At this time, the aftertreatment efficiency is too low, the aftertreatment hydrogen nozzle 109 is closed, and the injection of aftertreatment H2 is not performed.

[0059] When the engine cooling water temperature rises to the normal level (i.e. reaches the first preset temperature c ℃), the exhaust gas temperature detected by the temperature detector 104 is obtained, if the exhaust gas temperature is lower than the first target temperature a ℃, the cooling water control valve 108 is controlled to be connected, and the second output end of the hydrogen distribution proportional valve 106 is controlled to be closed, so that the cooling water flows through the second vaporizer 107, and the liquid hydrogen flows into the first vaporizer 105, and the liquid hydrogen is vaporized in the second vaporizer 107 by the cooling water. At this time, since the first vaporizer 105 is in a non-working state, the exhaust gas directly flows to the exhaust treatment circuit through the first vaporizer 105, so that the exhaust gas temperature rises rapidly, and the aftertreatment conversion efficiency requirement is met.

[0060] At this time, the aftertreatment efficiency is too low, that is, as shown in Figure 2 , the exhaust gas temperature is lower than a ℃, the H2-SCR catalyst 101 is in a low-efficiency working state, the aftertreatment hydrogen nozzle 109 is closed, and the injection of aftertreatment H2 is not performed.

[0061] If the exhaust gas temperature is between the first target temperature a ℃ and the first switching temperature a0 ℃, the cooling water control valve 108 is controlled to be connected, and the second output end of the hydrogen distribution proportional valve 106 is controlled to be closed, so that the cooling water flows through the second vaporizer 107, and the liquid hydrogen is vaporized through the second vaporizer 107, so that the exhaust gas temperature continues to rise. At this time, as shown in Figure 2 , the exhaust gas temperature is between a ℃ and a0 ℃, the H2-SCR catalyst 101 is in a high-efficiency working state, the aftertreatment hydrogen nozzle 109 is opened, and the injection of hydrogen is closed-loop controlled according to the front and rear NOX sensors to purify the NOX pollutants.

[0062] If the exhaust gas temperature is between the first switching temperature a0℃ and the second switching temperature b0℃, or the exhaust gas temperature is between the first target temperature b0℃ and the first switching temperature b0℃, the hydrogen distribution proportional valve 106 is controlled to be closed or connected, and the liquid hydrogen in the external liquid hydrogen tank 112 is controlled to enter the exhaust gas heating vaporization circuit and the cooling water heating vaporization circuit, that is, the distribution proportion of the hydrogen distribution proportional valve 106 and the opening and closing of the cooling water control valve 108 are controlled, so that the liquid hydrogen is reasonably distributed between the first vaporizer 105 and the second vaporizer 107, the exhaust gas temperature can be maintained between a0 and b0, the exhaust gas temperature reaching the H2-SCR catalyst 101 can be continuously maintained in the preferred temperature range, and the H2-SCR can better meet the application in the full working condition of the hydrogen internal combustion engine. At this time, the H2-SCR catalyst 101 is in a high-efficiency working state, and the aftertreatment hydrogen nozzle 109 is opened, and the hydrogen injection is closed-loop controlled according to the front and rear NOX sensors to purify the NOX pollutants.

[0063] For example, controlling the hydrogen distribution proportional valve 106 and the cooling water control valve 108 to reasonably distribute the liquid hydrogen between the first vaporizer 105 and the second vaporizer 107 can be: when the exhaust gas temperature is close to the upper limit of a0℃ to b0℃, the first output end of the hydrogen distribution proportional valve 106 is controlled to be closed (that is, the proportion of the first output end of the hydrogen distribution proportional valve 106 is 100%, and the proportion of the second output end is 0%), and the cooling water control valve 108 is controlled to be opened, so as to reduce the exhaust gas temperature; when the exhaust gas temperature is close to the lower limit of a0℃ to b0℃, the second output end of the hydrogen distribution proportional valve 106 is controlled to be closed (that is, the proportion of the first output end of the hydrogen distribution proportional valve 106 is 0%, and the proportion of the second output end is 100%), and the cooling water control valve 108 is controlled to be closed, so as to keep the exhaust gas temperature in a rising state; when the exhaust gas temperature is in the middle zone of a0℃ to b0℃, the proportion of the first output end of the hydrogen distribution proportional valve 106 is controlled to be 50%, the proportion of the second output end is controlled to be 50%, and the cooling water control valve 108 is controlled to be closed.

[0064] If the exhaust gas temperature is greater than the second target temperature b0℃, the cooling water control valve 108 is controlled to be opened, and the first output end of the hydrogen distribution proportional valve 106 is controlled to be closed, so that the liquid hydrogen is completely liquefied in the exhaust gas first vaporizer 105, the exhaust gas temperature is reduced through the heat absorption of the liquid hydrogen vaporization, and the requirement of the H2-SCR conversion efficiency is met. At this time, as shown in FIG. 6, the aftertreatment hydrogen nozzle 109 is opened, and the hydrogen injection is closed-loop controlled according to the front and rear NOX sensors to purify the NOX pollutants. Figure 2

[0065] ​The device can solve the problem that the H2-SCR cannot meet the application requirement of the hydrogen internal combustion engine in all working conditions by keeping the exhaust gas temperature input into the H2-SCR catalyst in a high-efficiency interval; the hydrogen internal combustion engine hydrogen injection system and the H2-SCR replace the NH3-SCR, the NH3-SCR urea injection system is reduced, the system complexity and cost are reduced, the low-temperature conversion efficiency of the NH3-SCR is low, and the crystallization problem is solved; the problem of insufficient liquid hydrogen vaporization caused by heating the liquid hydrogen by the engine cooling water is avoided, the engine cooling water temperature is sharply reduced due to the large heat absorption of the liquid hydrogen vaporization, the engine economy is affected, the influence of the hydrogen vaporization heat absorption on the cooling water vaporizer and the engine performance is reduced by the exhaust gas heating vaporizer, and the system reliability is improved; when the exhaust gas is in a high-temperature state, the first vaporizer absorbs the exhaust gas heat to reduce the exhaust temperature, so that the H2-SCR can cover all engine operating conditions, the first vaporizer is adopted to reduce the influence of the hydrogen vaporization heat absorption on the cooling water vaporizer and the engine performance, and the system reliability is improved.

[0066] In summary, the hydrogen internal combustion engine nitrogen oxide emission device provided by the embodiment of the present application can solve the problem of engine performance reduction caused by the fact that the engine cooling water is generally used to heat and vaporize liquid hydrogen, the device uses an exhaust gas heating vaporization loop and / or a cooling water heating vaporization loop to vaporize liquid hydrogen, solves the problem of insufficient liquid hydrogen vaporization caused by heating the liquid hydrogen by the engine cooling water, avoids the problem of sharp reduction of the engine cooling water temperature caused by the large heat absorption of the liquid hydrogen vaporization, and thus improves the vehicle engine economy and greatly improves the user experience.

[0067] In a second aspect, an embodiment of the present application provides the following technical scheme:

[0068] A vehicle 500, as shown in the figure, comprises a vehicle body 501 and the hydrogen internal combustion engine nitrogen oxide emission device 502 of any one of the first aspect. Figure 4

[0069] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program codes.

[0070] ​The present application is described in reference to the flowchart illustrations and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks

[0071] These computer program instructions can also be stored in a computer- readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the function specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks

[0072] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart illustrations and / or block diagrams block or blocks. Figure 1 one or more flowcharts and / or blocks Figure 1 one or more flowcharts and / or blocks

[0073] While the preferred embodiments of the application have been described, additional variations and modifications can be made to the embodiments by those of skill in the art once they have the benefit of the present disclosure without departing from the spirit and scope of the application. Accordingly, the attached claims are intended to cover all such variations and modifications as falling within the scope of the application.

[0074] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A nitrogen oxide emission device for a hydrogen internal combustion engine, characterized in that, include: The exhaust gas heating and vaporization circuit, the cooling water heating and vaporization circuit, the exhaust gas treatment circuit, and the aftertreatment controller are provided. The exhaust gas heating and vaporization circuit includes a hydrogen internal combustion engine, a first vaporizer, and a hydrogen distribution proportional valve. The aftertreatment controller is electrically connected to the electrical control unit of the hydrogen internal combustion engine and is electrically connected to the hydrogen distribution proportional valve. The exhaust outlet of the hydrogen internal combustion engine is connected to the input end of the exhaust gas treatment circuit through the first vaporizer, which is used to transfer the waste heat of the exhaust gas to the first vaporizer. The input end of the hydrogen distribution proportional valve is connected to a liquid hydrogen tank. The first output end of the hydrogen distribution proportional valve is connected to the liquid hydrogen inlet of the first vaporizer. The hydrogen outlet of the first vaporizer is connected to the hydrogen inlet of the hydrogen internal combustion engine. This is used to heat and vaporize the liquid hydrogen flowing into the first vaporizer before it flows into the hydrogen internal combustion engine. The second output end of the hydrogen distribution proportional valve is connected to the liquid hydrogen inlet of the cooling water heating and vaporization circuit. This is used to heat and vaporize the liquid hydrogen flowing into the cooling water heating and vaporization circuit before it flows into the hydrogen internal combustion engine. The aftertreatment controller is used to acquire the cooling water temperature of the hydrogen internal combustion engine during cold start; if the cooling water temperature reaches a first preset temperature, it acquires the exhaust gas temperature output by the exhaust gas heating and vaporization circuit; if the exhaust gas temperature is lower than a first target temperature, it controls the cooling water heating and vaporization circuit to connect with the cooling water pipeline of the hydrogen internal combustion engine, and controls liquid hydrogen from the external liquid hydrogen tank to enter the cooling water heating and vaporization circuit; if the exhaust gas temperature is higher than a second target temperature, it controls the cooling water heating and vaporization circuit to disconnect from the cooling water pipeline of the hydrogen internal combustion engine, and controls liquid hydrogen from the external liquid hydrogen tank to enter the exhaust gas heating and vaporization circuit; the first target temperature is lower than the second target temperature.

2. The apparatus as claimed in claim 1, characterized in that, The cooling water heating and vaporization circuit includes the hydrogen internal combustion engine, the second vaporizer, and the cooling water control valve, and the aftertreatment controller is electrically connected to the cooling water control valve. The cooling water outlet of the hydrogen internal combustion engine flows back to the hydrogen internal combustion engine through the cooling water control valve and the second vaporizer, in order to transfer heat to the second vaporizer. The second output terminal of the hydrogen distribution proportional valve is connected to the liquid hydrogen inlet of the second vaporizer, and the hydrogen outlet of the second vaporizer is connected to the hydrogen inlet of the hydrogen internal combustion engine. This valve is used to heat and vaporize the liquid hydrogen flowing into the second vaporizer, and the vaporized hydrogen flows to the hydrogen internal combustion engine.

3. The apparatus as described in claim 1, characterized in that, The exhaust gas heating and vaporization circuit also includes a temperature detector, which is electrically connected to the aftertreatment controller. The temperature detector is located between the first vaporizer and the input terminal of the exhaust gas treatment circuit and is used to monitor the temperature of the exhaust gas flowing into the exhaust gas treatment circuit.

4. The apparatus as claimed in claim 1, characterized in that, The exhaust gas treatment circuit includes: a catalyst reducer containing a reduction catalyst, wherein the first vaporizer is connected to the input end of the catalyst reducer.

5. The apparatus as described in claim 4, characterized in that, The reduction catalyst is an H2-SCR catalyst.

6. The apparatus as claimed in claim 4, characterized in that, The exhaust gas treatment circuit further includes: a first nitrogen oxide sensor, electrically connected to the aftertreatment controller, wherein the first nitrogen oxide sensor is disposed at the output end of the reduction catalyst and is used to monitor the nitrogen oxide concentration of the exhaust gas after treatment by the reduction catalyst.

7. The apparatus as claimed in claim 1, characterized in that, The exhaust gas heating and vaporization circuit also includes an after-treatment hydrogen nozzle, which is electrically connected to the after-treatment controller. The after-treatment hydrogen nozzle is located between the exhaust gas output end of the hydrogen internal combustion engine and the exhaust gas input port of the first vaporizer.

8. The apparatus as claimed in claim 7, characterized in that, The post-treatment hydrogen nozzle is also connected to the hydrogen output port of the first vaporizer.

9. The apparatus as claimed in claim 1, characterized in that, The exhaust gas heating and vaporization circuit also includes a second nitrogen oxide sensor, which is electrically connected to the aftertreatment controller. The second nitrogen oxide sensor is located between the exhaust gas output end of the hydrogen internal combustion engine and the exhaust gas input port of the first vaporizer, and is used to monitor the nitrogen oxide concentration in the exhaust gas.

10. A vehicle, characterized in that, include: The vehicle body and the nitrogen oxide emission device for the hydrogen internal combustion engine according to any one of claims 1-9.

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