Exhaust gas aftertreatment device, vehicle and control method

Abstract

The application provides a tail gas aftertreatment device, a vehicle and a control method. The tail gas aftertreatment device comprises a coupling catalysis part, which is communicated with an engine exhaust manifold; an adsorbent part, which is communicated with an exhaust pipeline of the coupling catalysis part; a muffling unit, an inlet end of the muffling unit is respectively and communicatively arranged with an outlet end of the coupling catalysis part and an outlet end of the adsorbent part; and an exhaust gas backflow pipeline, one end of the exhaust gas backflow pipeline is communicated with a pipeline between the adsorbent part and the muffling unit, and the other end of the exhaust gas backflow pipeline is communicated with a pipeline between the engine exhaust manifold and an inlet end of the coupling catalysis part, so that the content of pollutants in tail gas is effectively reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicles, in particular to a tail gas aftertreatment device, a vehicle and a control method. BACKGROUND

[0002] The upcoming implementation of the national sixth B emission standard limit value for light gasoline vehicles is more stringent than the current national sixth A, and the introduction of the RDE actual driving pollutant emission test and the increase in the emission durability mileage bring new challenges to the gasoline vehicle exhaust aftertreatment scheme, technical route and control method. Under the multiple pressures of the national sixth B emission standard limit value, the increase in durability mileage and the actual driving pollutant emission test RDE, the traditional gasoline vehicle aftertreatment device has the following problems:

[0003] In the national sixth B emission test I type test WLTC cycle, the HC and NOx pollutant emissions in the low-speed cold start stage usually account for more than 75% and 50% of the total emission amount of the entire test cycle. The aftertreatment catalyst (three-way catalyst) needs to reach a temperature of at least 250-300°C to ignite. Therefore, in the first few tens of seconds of cold start, the temperature of the catalyst cannot reach the ignition temperature, and most of the HC and NOx pollutants will be directly discharged from the exhaust pipe, resulting in a significant increase in the proportion of HC and NOx pollutants in the low-speed stage. SUMMARY

[0004] The main purpose of the present application is to provide a tail gas aftertreatment device, a vehicle and a control method to solve the problem of high content of vehicle tail gas pollutants in the prior art.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a tail gas aftertreatment device is provided, which comprises a coupling catalysis part in communication with an engine exhaust manifold; an adsorbent component in communication with an exhaust pipe of the coupling catalysis part; a muffler unit, the inlet end of the muffler unit is respectively in communication with the outlet end of the coupling catalysis part and the outlet end of the adsorbent component; an exhaust gas recirculation pipe, one end of the exhaust gas recirculation pipe is in communication with the pipe between the adsorbent component and the muffler unit, and the other end of the exhaust gas recirculation pipe is in communication with the pipe between the engine exhaust manifold and the inlet end of the coupling catalysis part.

[0006] Further, the coupling catalysis part comprises: a catalyst component, a front oxygen sensor is installed at the inlet end of the catalyst component, and a rear oxygen sensor is installed at the outlet end of the catalyst component; a particulate filter, the catalyst component and the particulate filter are integrated in a first housing, and a noble metal catalyst is coated on the particulate filter.

[0007] Further, a front temperature sensor is arranged on the first housing, and a rear temperature sensor is arranged on a gas outlet end cone at the gas outlet end of the particulate filter, and the gas outlet end cone is connected with the rear end of the first housing.

[0008] Further, a front pressure sampling point is arranged on the first shell corresponding to the intake end of the particle trap, a rear pressure sampling point is arranged on the outlet end cone corresponding to the outlet end of the particle trap, the front pressure sampling point is connected to one end of the front pressure difference pipe, the rear pressure sampling point is connected to one end of the rear pressure difference pipe, the other end of the front pressure difference pipe and the other end of the rear pressure difference pipe are connected to the pressure difference sensor.

[0009] Further, the adsorbent component comprises: an HC trap, a flow sensor and a temperature sensor are arranged on the inlet end of the HC trap; an NO X trap, the NO X trap is integrated with the HC trap in a second shell, the inlet end of the second shell is communicated with the outlet end of the first shell, and the outlet end of the second shell is communicated with the muffler unit and the exhaust gas recirculation pipeline.

[0010] Further, the exhaust gas recirculation pipeline is provided with an airflow guide pipe at the position communicated with the inlet end of the catalyst component, the airflow guide pipe is located in the pipeline communicated between the engine exhaust manifold and the first shell, and the outlet side of the airflow guide pipe is arranged towards the side of the first shell.

[0011] Further, the inlet pipe of the coupling catalytic part is connected with the engine exhaust manifold through an inlet flange, the inlet flange comprises: a flange body, an annular connecting flange is formed on the inner circular side of the flange body, a second annular groove and a first annular stress groove are sequentially arranged between the annular connecting flange and the outer edge of the flange body, the groove wall height of the second annular groove is greater than the groove wall height of the first annular stress groove, one end of the inlet pipe extends into the second annular groove, and the annular connecting flange extends into the inlet pipe.

[0012] Further, a bushing part is arranged in the inlet end cone of the catalyst component, a first end of the bushing part is connected with the inlet pipe and the inlet end cone, and a second end of the bushing part is in a horn shape, the outer surface of the second end of the bushing part is arranged at a distance from the inner surface of the inlet end cone to form an air layer.

[0013] Further, the exhaust gas aftertreatment device further comprises a bypass pipeline, a first end of the bypass pipeline is connected to the pipeline between the coupling catalytic part and the adsorbent component through a first three-way valve, a second end of the bypass pipeline is communicated with the muffler unit, and one end of the exhaust gas recirculation pipeline is connected to the pipeline between the adsorbent component and the muffler unit through a second three-way valve.

[0014] According to another aspect of the present application, a vehicle is provided, the vehicle comprising an exhaust gas aftertreatment device, the exhaust gas aftertreatment device being the exhaust gas aftertreatment device of the above-mentioned embodiments.

[0015] According to another aspect of the present application, a control method of an exhaust gas aftertreatment device is provided, the control method being used to control the exhaust gas aftertreatment device of the above-mentioned embodiments, the control method comprising the following steps: obtaining start information of the vehicle; determining, according to the start information, that the vehicle is in a cold start working condition, controlling the first three-way valve and the second three-way valve of the vehicle to be opened, so that the exhaust gas of the vehicle flows through the flow catalyst component and the particulate filter, the HC trap and the NO X trap in sequence; obtaining an inlet temperature of the HC trap, and in the case that the inlet temperature meets a preset condition, controlling the first three-way valve and the second three-way valve to be in a conducting state of being opened, so that the engine exhaust gas flows to the catalyst component and the particulate filter and then flows to the muffler unit, while the second three-way valve is completely closed; obtaining an exhaust temperature of the vehicle, and controlling the first three-way valve and the second three-way valve to be in a conducting state of being opened, so that the engine exhaust gas flows to the adsorbent component through the coupling catalyst, and the exhaust gas passing through the adsorbent component is guided to the exhaust gas recirculation pipeline.

[0016] Further, the control method further comprises: obtaining a time required for the desorption of pollutants to be completed; and based on the time required for the desorption of pollutants to be completed, controlling the first three-way valve and the second three-way valve to be in a conducting state of being opened, so that the first three-way valve guides the engine exhaust gas to the muffler unit entirely.

[0017] By arranging the coupling catalyst at a position close to the outlet of the engine exhaust manifold, the coupling catalyst can be rapidly heated, so that the content of pollutants in the exhaust gas can be effectively reduced. By arranging the adsorbent component at a position close to the outlet of the coupling catalyst, the temperature of the exhaust gas flowing through the coupling catalyst can be rapidly heated, so that the content of pollutants in the exhaust gas can be effectively reduced. The muffler unit is used to receive the exhaust gas flowing through the coupling catalyst and the adsorbent component or the exhaust gas flowing through the coupling catalyst only, so that in the case of high-temperature exhaust gas, the content of pollutants in the exhaust gas can be reduced by controlling the exhaust gas to flow through the coupling catalyst to the muffler unit, and in the case of low-temperature exhaust gas, the content of pollutants in the exhaust gas can be reduced by controlling the exhaust gas to flow through the coupling catalyst, the adsorbent component and then the muffler unit. The exhaust gas recirculation pipeline is arranged to make the exhaust gas having flowed through the coupling catalyst and the adsorbent component flow through the coupling catalyst and the adsorbent component again for catalytic oxidation, so that the content of pollutants in the exhaust gas can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and serve as an explanation of the illustrative embodiments of the present application, and are not intended to limit the present application unduly. In the drawings:

[0019] Figure 1Fig. 1 shows a structural schematic diagram of a first embodiment of an exhaust gas aftertreatment device according to the present application;

[0020] Figure 2 Fig. 2 shows a structural schematic diagram of a first embodiment of a gas flow guide tube of an exhaust gas aftertreatment device according to the present application;

[0021] Figure 3 Fig. 3 shows a structural schematic diagram of a coupling catalytic converter of an exhaust gas aftertreatment device according to the present application;

[0022] Figure 4 Fig. 4 shows a structural schematic diagram of an intake flange of an exhaust gas aftertreatment device according to the present application;

[0023] Figure 5 Fig. 5 shows a structural schematic diagram of an intake end cone of an exhaust gas aftertreatment device according to the present application.

[0024] Wherein, the above figures include the following reference signs:

[0025] 1, engine exhaust manifold; 2, catalytic converter component; 3, particulate trap;

[0026] 4, first three-way valve; 5, HC trap; 6, NO X trap;

[0027] 7, second three-way valve; 8, exhaust gas recirculation line; 9, front oxygen sensor;

[0028] 10, rear oxygen sensor; 11, front temperature sensor; 12, rear temperature sensor;

[0029] 13, front pressure difference pipe; 14, rear pressure difference pipe; 15, pressure difference sensor;

[0030] 16, flow sensor; 17, temperature sensor; 18, muffler unit;

[0031] 19, control unit; 20, gas flow guide tube;

[0032] 21, intake flange; 211, first annular stress groove; 212, second annular groove; 213, annular connecting flange;

[0033] 22, intake pipe; 23, intake end cone; 24, air layer;

[0034] 25, bushing; 26, outlet end cone; 30, bypass line. DETAILED DESCRIPTION

[0035] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0036] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of this application is thorough and complete, and that the concept of these exemplary embodiments is fully conveyed to those skilled in the art. In the drawings, for clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to denote the same devices, and therefore their description will be omitted.

[0039] Combination Figures 1 to 5 As shown, according to a specific embodiment of the present invention, an exhaust gas aftertreatment device is provided.

[0040] Specifically, such as Figure 1 As shown, the exhaust aftertreatment device includes a coupling catalytic converter, an adsorbent component, a muffler unit 18, and an exhaust return pipe 8. The coupling catalytic converter is connected to the engine exhaust manifold 1; the adsorbent component is connected to the exhaust pipe of the coupling catalytic converter; the inlet end of the muffler unit 18 is connected to the outlet end of the coupling catalytic converter and the outlet end of the adsorbent component, respectively; one end of the exhaust return pipe 8 is connected to the pipe connecting the adsorbent component and the muffler unit 18, and the other end of the exhaust return pipe 8 is connected to the pipe connecting the engine exhaust manifold 1 and the inlet end of the coupling catalytic converter.

[0041] In this embodiment, the coupling catalytic part is arranged near the outlet of the engine exhaust manifold 1, so that the coupling catalytic part can be quickly warmed up to effectively reduce the pollutant content in the exhaust gas. The adsorbent part is arranged near the outlet of the coupling catalytic part, so that the temperature conducted to the coupling catalytic part is still delayed during the low-speed stage cold start process, resulting in a still high cold start pollutant emission. Therefore, the exhaust gas from the coupling catalytic part is further adsorbed by the adsorbent part, thereby effectively reducing the pollutant content in the exhaust gas. The muffler unit 18 is used to receive the exhaust gas flowing through the coupling catalytic part and the adsorbent part or only the exhaust gas flowing through the coupling catalytic part. In the case of high-temperature exhaust gas, controlling the exhaust gas to flow through the coupling catalytic part to the muffler unit 18 can achieve the reduction of the pollutant content. When the temperature is low, controlling the exhaust gas to flow through the coupling catalytic part, the adsorbent part and then the muffler unit 18 can achieve the reduction of the pollutant content. The exhaust gas return pipeline 8 is arranged to make the exhaust gas having flowed through the coupling catalytic part and the adsorbent part flow through the coupling catalytic part and the adsorbent part again for catalytic oxidation, thereby reducing the pollutant content in the exhaust gas.

[0042] Further, the exhaust gas aftertreatment device comprises a control unit 19 for overall control of the exhaust gas aftertreatment device. The exhaust gas aftertreatment device further comprises two three-way valves. The first three-way valve 4 is arranged behind the coupling catalytic converter and can adjust the direction of the gas flow to the adsorbent part or the muffler unit 18. The second three-way valve 7 is arranged behind the adsorbent part and can adjust the direction of the gas flow to the exhaust gas return pipeline 8 or the muffler unit 18 or completely close.

[0043] Further, the coupling catalytic part comprises a catalyst part 2, a front oxygen sensor 9 is installed at the inlet end of the catalyst part 2, and a rear oxygen sensor 10 is installed at the outlet end of the catalyst part 2. A particulate filter 3 is integrated with the catalyst part 2 in a first housing, and the particulate filter 3 is coated with a noble metal catalyst. In order to quickly warm up or improve the low-temperature conversion capability of the coupling catalytic part, the coupling catalytic part is usually installed near the outlet of the engine exhaust manifold to quickly warm up the catalyst. However, due to the influence of the catalyst coating material, the temperature conducted to the catalytically active material still has a delay, and the cold start pollutant emission cannot be effectively reduced. The particulate filter 3 is coated with a small amount of noble metal catalyst, which helps to regenerate and burn particulate matter. At the same time, HC is oxidized due to the action of the catalyst during the regeneration of particulate matter, thereby reducing particulate matter and HC emissions. The front oxygen sensor 9 and the rear oxygen sensor 10 are used to detect the oxygen concentration in the exhaust gas, and the front oxygen sensor 9 sends a feedback signal to the engine control unit 19, which controls the increase or decrease of the fuel injection amount of the fuel injector, thereby controlling the air-fuel ratio of the mixture near the theoretical value, so that the conversion efficiency of the catalyst is optimal.

[0044] The noble metals platinum, rhodium and palladium are coated on the ceramic carrier inside the catalyst component 2 to purify gaseous pollutants CO, HC, NOx in the exhaust gas; the noble metals platinum and rhodium are coated on the wall-flow carrier inside the particulate filter 3 to reduce the emission of part of the gaseous pollutants while reducing particulate matter PN, PM.

[0045] Further, the first shell is provided with a front temperature sensor 11, and a rear temperature sensor 12 is arranged on the outlet end cone 26 at the outlet end of the particulate filter 3, and the outlet end cone 26 is connected to the rear end of the first shell. The front temperature sensor 11 and the rear temperature sensor 12 are used to detect the exhaust gas temperature before and after the particulate filter 3.

[0046] According to the requirements of the national sixth emission regulation, the complete damage or absence of the particulate filter 3 should be identified by the differential pressure change rate before and after the particulate filter 3. However, due to the arrangement of the pressure taking port behind the traditional particulate filter 3 on the straight section of the outlet pipe, the discrimination of the removal diagnosis of the particulate filter 3 is reduced, and the engine fault light of the vehicle may occasionally be constant, so that the OBD system confirms the GPF check as a false alarm, affecting the user's driving experience. In order to solve this problem, a front pressure taking point is arranged on the first shell corresponding to the inlet end of the particulate filter 3, and a rear pressure taking point is arranged on the outlet end cone 26 corresponding to the outlet end of the particulate filter 3. One end of the front pressure taking point is connected to one end of the front differential pressure pipe 13, and one end of the rear pressure taking point is connected to one end of the rear differential pressure pipe 14. The other end of the front differential pressure pipe 13 and the other end of the rear differential pressure pipe 14 are connected to the differential pressure sensor 15. The differential pressure sensor 15 is used to detect the differential pressure before and after the particulate filter 3. The control unit 19 calculates and evaluates the carbon load in the particulate filter 3 according to the detected temperature sensor signal and the differential pressure sensor signal, and performs timely regeneration and protects the particulate filter 3 from being damaged by high temperature. The pressure taking point behind the particulate filter 3 is arranged on the outlet end cone 26. This arrangement increases the differential pressure threshold value of the standard sample and the empty pipe sample of the particulate filter 3, improves the differential pressure signal quality compared with the existing arrangement of the rear pressure taking point of the particulate filter 3 on the straight pipe, and solves the problem of false alarm of the OBD system such as loss of GPF. Further, as shown in Figure 3 The front and rear pipes connected to the differential pressure sensor 15 continuously go upward with an angle greater than 20° with the horizontal plane, effectively preventing the pipe from being blocked by water vapor icing at low temperature in the exhaust gas, affecting regeneration.

[0047] Further, the adsorbent component includes: an HC trap 5, a flow sensor 16 and a temperature sensor 17 are installed at the inlet end of the HC trap 5; a NO X trap 6, a temperature sensor 18 is installed at the inlet end of the NO XThe filter 6 and HC filter 5 are integrated in the second housing. The inlet end of the second housing is connected to the outlet end of the first housing, and the outlet end of the second housing is connected to the muffler unit 18 and the exhaust return pipe 8. The detected flow and temperature data can be transmitted to the engine control unit 19 in real time. The control unit 19 can then, based on the received flow and temperature data, and considering the HC filter 5 and NO... X The adsorption and desorption models of the trap 6 are compared, calculated, and the airflow direction of the first three-way valve 4 and the second three-way valve 7 is controlled.

[0048] like Figure 2 As shown, an airflow guide pipe 20 is provided at the connection point between the exhaust return pipe 8 and the inlet end of the catalyst component 2. The airflow guide pipe 20 is located in the pipe connecting the engine exhaust manifold 1 and the first housing, and the outlet side of the airflow guide pipe 20 faces the first housing. The airflow guide pipe 20 is used to prevent the exhaust gas discharged from the engine from flowing directly into the exhaust return pipe 8.

[0049] Because the intake pipe 22 and the inner surface of the intake flange 21 overlap in the existing technology, after the intake pipe 22 and the intake flange 21 are welded, the intake pipe may crack due to the failure to release the welding heat stress, which may easily lead to emission durability problems.

[0050] To solve the above problems, such as Figure 4 As shown, the intake pipe 22 of the coupled catalytic converter is connected to the engine exhaust manifold 1 via an intake flange 21. The intake flange 21 includes a flange body, an annular connecting flange 213 formed on the inner circular side of the flange body, and a second annular groove 212 and a first annular stress groove 211 sequentially arranged between the annular connecting flange 213 and the outer edge of the flange body. The wall height of the second annular groove 212 is greater than the wall height of the first annular stress groove 211. One end of the intake pipe 22 extends into the second annular groove 212, and the annular connecting flange 213 extends into the intake pipe 22. The first annular stress groove 211 can effectively release welding thermal stress and reduce thermal deformation. The intake pipe 22 is fitted onto the annular connecting flange 213. When the impact force of the high-temperature gas flow is relatively large, the annular connecting flange 213 provides support for the intake pipe 22, thereby improving the stability of the connection between the intake pipe 22 and the second annular groove 212. Durability tests have verified that this structure significantly improves the emission durability performance of the catalytic converter.

[0051] To enable the catalyst component 2 to heat up quickly, the coupled catalyst is usually arranged close to the engine turbocharger outlet. Due to the thermal fatigue impact of the high-temperature exhaust of the engine, the inlet round corner of the catalyst component 2 is prone to cracking.

[0052] To solve the above problems, such as Figure 5As shown, the air inlet end cone 23 of the catalyst component 2 is provided with a bushing component 25, the first end of the bushing component 25 is connected with the air inlet pipe 22 and the air inlet end cone 23, and the second end of the bushing component 25 is flared, the outer surface of the second end of the bushing component 25 is provided with a distance from the inner surface of the air inlet end cone 23 to form an air layer 24. The air layer 24 reduces the temperature at the rounded corner of the air inlet end cone 23 by about 30℃, the provision of the bushing component 25 in the air inlet end cone 23 of the catalyst component 2 effectively improves the cycle number of the thermal fatigue of the air inlet end cone, and makes the flow uniformity of the carrier air inlet end surface more optimal; and the internal flow passage angle A of the bushing component 25 is 84°, which makes the flow uniformity of the carrier air inlet end surface more optimal, and is more beneficial to exhaust gas purification.

[0053] Further, the exhaust gas aftertreatment device further comprises a bypass pipeline 30, the first end of the bypass pipeline 30 is connected to the pipeline between the coupled catalytic component and the adsorbent component through a first three-way valve 4, the second end of the bypass pipeline 30 is in communication with the muffler unit 18, and one end of the exhaust gas recirculation pipeline 8 is connected to the pipeline between the adsorbent component and the muffler unit 18 through a second three-way valve 7. The first three-way valve 4 can adjust the direction of the gas flow to the adsorbent component or the muffler unit 18; the second three-way valve 7 can adjust the direction of the gas flow to the exhaust gas recirculation pipeline 8 or the muffler unit 18 or completely close.

[0054] The control unit 19 is electrically connected with the first three-way valve 4, the second three-way valve 7, the front oxygen sensor 9, the rear oxygen sensor 10, the front temperature sensor 11, the rear temperature sensor 12, the differential pressure sensor 15, the flow sensor 16 and the temperature sensor 17.

[0055] According to another aspect of the present application, a vehicle is provided, the vehicle comprising an exhaust gas aftertreatment device, the exhaust gas aftertreatment device being the exhaust gas aftertreatment device of the above-mentioned embodiments.

[0056] According to another aspect of the present application, a control method of an exhaust gas aftertreatment device is provided, the control method being used for controlling the exhaust gas aftertreatment device of the above-mentioned embodiments, and the control method comprising the following steps: obtaining starting information of the vehicle; determining that the vehicle is in a cold starting working condition according to the starting information, controlling the first three-way valve 4 and the second three-way valve 7 of the vehicle to be opened, so that the exhaust gas of the vehicle passes through the flow catalyst component 2 and the particulate filter 3, the HC trap 5 and the NO XThe trap 6; the inlet temperature of the HC trap 5 is obtained, and in the case that the inlet temperature meets the preset condition, the first three-way valve 4 and the second three-way valve 7 are controlled to be in the open conduction state, so that the engine exhaust gas flows to the catalyst component 2 and the particulate trap 3 and then flows to the muffler unit 18, and the second three-way valve 7 is completely closed; the exhaust temperature of the vehicle is obtained, and the first three-way valve 4 and the second three-way valve 7 are controlled to be in the open conduction state, so that the engine exhaust gas flows to the adsorbent component via the coupled catalyst, and the exhaust gas passing through the adsorbent component is guided to the exhaust gas recirculation pipeline 8.

[0057] Further, the control method further comprises: obtaining the time required for the pollutant desorption to be completed; and based on the time required for the desorption to be completed, controlling the first three-way valve 4 and the second three-way valve 7 to be in the open conduction state, so that the first three-way valve 4 guides the engine exhaust gas to the muffler unit 18.

[0058] The control method of the exhaust aftertreatment device provided by the application is as follows: when the automobile is in the cold start working condition, the control unit 19 controls the first three-way valve 4 and the second three-way valve 7 to be open, so that the exhaust gas flows through the catalyst component 2 and the particulate trap 3, the HC trap 5 and the NO X The trap 6 in sequence, and at this time, the engine exhaust temperature has not reached the light-off temperature of the catalyst, and the catalyst cannot effectively purify the exhaust gas pollutants; at this stage, the HC and NOx pollutants in the exhaust gas are adsorbed in the HC trap 5 and the NOx trap 6 in the adsorbent component. When the inlet temperature T1 of the adsorbent component rises to a difference ΔT (ΔT = T1-T0) between the inlet temperature T1 of the adsorbent component and the pollutant desorption critical temperature T0 of the trap catalyst) is less than 10℃, the control unit 19 controls the first three-way valve 4 and the second three-way valve 7 to make the engine exhaust gas flow to the catalyst component 2 and the particulate trap 3, and then flow to the muffler unit 18, and the second three-way valve 7 is completely closed.

[0059] When the engine runs to high speed and high load conditions, the exhaust temperature reaches the optimal working temperature of the three-way catalyst, the control unit 19 jointly controls the first three-way valve 4 and the second three-way valve 7, and the engine exhaust gas flows to the adsorbent component through the coupling catalyst, and the exhaust gas passing through the adsorbent component is guided to the exhaust gas recirculation pipeline 8. The control unit 19 detects the temperature and flow data based on the flow sensor 16 and temperature sensor 17 installed at the inlet of the adsorbent component, and calculates the time required for the desorption of pollutants based on the adsorption and desorption model. When the desorption completion time is reached, the control unit 19 directs all engine exhaust gas to the muffler unit 18 through the first three-way valve 4, while closing the second three-way valve 7. After the above-mentioned linkage control of the control unit 19, the HC and NOx pollutants emitted during the cold start stage can be efficiently treated, and the overall pollutant emission can be greatly reduced, meeting the requirements of the national six b regulation limit value. At the same time, the first three-way valve 4 and the second three-way valve 7 are both arranged behind the coupling catalyst, avoiding the damage of high temperature gas to the three-way valve component, and the reliability and durability of the component are thus guaranteed. The above-mentioned desorption critical temperature of the captured pollutants and the optimal working temperature of the three-way catalyst are determined by catalyst monomer performance test, and the related data are stored in the control unit 19.

[0060] In another embodiment of the present application, the aftertreatment technology route adopted by the present application further solves the ultra-low emission requirement required by the upgrading of emission regulations from national six a to national six b. In the national six light-duty vehicle exhaust emission test I type test, from the pollutant cold start proportion data, during the low speed stage cold start process, due to the low exhaust temperature, the temperature conducted to the catalytic active material will still exist delay, and the cold start pollutant emission cannot be effectively reduced. In order to solve the deficiency of the prior art, an HC trap 5 and a NOx trap 6 are added behind the catalyst component 2 and the particulate filter 3, and the HC trap 5 and the NOx trap 6 are respectively connected to the first three-way valve 4 and the second three-way valve 7. The HC trap 5 and the NOx trap 6 are respectively connected to the first three-way valve 4 and the second three-way valve 7. The HC trap 5 and the NOx trap 6 are respectively connected to the first three-way valve 4 and the second three-way valve 7. The HC trap 5 and the NOx trap 6 are respectively connected to the first three-way valve 4 and the second three-way valve 7. XThe adsorption component of the trap 6 has a three-way valve added before and after it. A temperature sensor and a flow sensor are installed at the inlet of the adsorbent component. The temperature and flow data collected by the sensors are transmitted to the engine control unit 19 in real time. The control unit 19 detects, compares, and controls the working state of the downstream three-way valve based on the detected temperature and flow data. This allows it to adjust the exhaust airflow direction to point towards the exhaust return pipe, the exhaust muffler, or to completely close it, achieving joint control of the first three-way valve 4 and the second three-way valve 7. After the above-mentioned linkage control, HC and NOx pollutants emitted during the cold start phase can be efficiently treated. The technical solution of this invention was demonstrated through emission comparison tests on a vehicle with a conventional aftertreatment system meeting China VI emission standards. Under the condition that the catalyst carrier, coating type, coating amount, and precious metal content were all consistent, each aftertreatment system was tested three times according to the WLTC standard, and the average value was taken as the final result. The technical solution of this invention reduces HC and NOx emissions by 61.7% and 54% respectively in the WLTC cycle test compared to conventional aftertreatment systems. Lower pollutant emissions are more conducive to the vehicle meeting the emission limits of the upcoming China VI b regulations I test and the real-world driving pollutant emission RDE test.

[0061] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0062] In addition to the above, it should be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this invention.

[0063] In the above embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the relevant description of other embodiments.

[0064] The above descriptions are only the preferred embodiments of the present application and are not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An exhaust gas aftertreatment device, characterized in that The exhaust gas aftertreatment device comprises: a coupling catalytic part in communication with an engine exhaust manifold (1); an adsorbent part in communication with an exhaust pipeline of the coupling catalytic part; a muffler unit (18), an inlet end of the muffler unit (18) being in communication with an outlet end of the coupling catalytic part and an outlet end of the adsorbent part respectively; an exhaust gas recirculation pipeline (8), one end of the exhaust gas recirculation pipeline (8) being in communication with a pipeline connecting the adsorbent part and the muffler unit (18), the other end of the exhaust gas recirculation pipeline (8) being in communication with a pipeline connecting the engine exhaust manifold (1) and an inlet end of the coupling catalytic part; the coupling catalytic part comprises: a catalyst part (2), a front oxygen sensor (9) being installed at an inlet end of the catalyst part (2), a rear oxygen sensor (10) being installed at an outlet end of the catalyst part (2); a particulate trap (3), the catalyst part (2) and the particulate trap (3) being integrated in a first housing, the particulate trap (3) being coated with a noble metal catalyst; the adsorbent part comprises: an HC trap (5), a flow sensor (16) and a temperature sensor (17) being installed at an inlet end of the HC trap (5); NO X trap (6), said NO X trap (6) is integrated with said HC trap (5) in a second housing, an inlet end of said second housing is communicated with an outlet end of said first housing, an outlet end of said second housing is communicated with said muffler unit (18) and said exhaust gas recirculation pipeline (8); the exhaust gas aftertreatment device further comprises a bypass pipeline (30), a first end of the bypass pipeline (30) being connected to a pipeline between the coupling catalytic part and the adsorbent part through a first three-way valve (4), a second end of the bypass pipeline (30) being in communication with the muffler unit (18), one end of the exhaust gas recirculation pipeline (8) being connected to a pipeline between the adsorbent part and the muffler unit (18) through a second three-way valve (7).

2. The exhaust gas aftertreatment device of claim 1, wherein, A front temperature sensor (11) is arranged on the first housing, a rear temperature sensor (12) is arranged on an outlet end cone (26) at an outlet end of the particulate trap (3), and the outlet end cone (26) is connected to a rear end of the first housing.

3. The exhaust gas aftertreatment device of claim 2, wherein, A front pressure sampling point is arranged on the first housing corresponding to an inlet end of the particulate trap (3), a rear pressure sampling point is arranged on the outlet end cone (26) corresponding to an outlet end of the particulate trap (3), one end of the front pressure differential pipe (13) is connected to the front pressure sampling point, one end of the rear pressure differential pipe (14) is connected to the rear pressure sampling point, and the other end of the front pressure differential pipe (13) and the other end of the rear pressure differential pipe (14) are connected to a pressure difference sensor (15).

4. The exhaust gas aftertreatment device of claim 1, wherein, An airflow guide pipe (20) is arranged at a position where the exhaust gas recirculation pipeline (8) is in communication with the inlet end of the catalyst part (2), the airflow guide pipe (20) is located in a pipeline connecting the engine exhaust manifold (1) and the first housing, and an outlet side of the airflow guide pipe (20) is arranged towards the first housing.

5. The exhaust gas aftertreatment device of claim 1, wherein, An inlet pipe (22) of the coupling catalytic part is connected to the engine exhaust manifold (1) through an inlet flange (21), and the inlet flange (21) comprises: The flange body is formed with an annular connecting flange (213) on the inner side, a second annular groove (212) and a first annular stress groove (211) are sequentially arranged between the annular connecting flange (213) and the outer edge of the flange body, the groove wall height of the second annular groove (212) is greater than that of the first annular stress groove (211), one end of the air inlet pipe (22) extends into the second annular groove (212), and the annular connecting flange (213) extends into the air inlet pipe (22).

6. The exhaust gas aftertreatment device of claim 5, wherein, A bushing part (25) is arranged in the air inlet end cone (23) of the catalyst part (2), the first end of the bushing part (25) is connected with the air inlet pipe (22) and the air inlet end cone (23), and the second end of the bushing part (25) is in a bell shape, the outer surface of the second end of the bushing part (25) is arranged at a distance from the inner surface of the air inlet end cone (23) to form an air layer (24).

7. A vehicle characterized by comprising: The vehicle comprises an exhaust gas aftertreatment device according to any one of claims 1 to 6.

8. A control method of an exhaust gas aftertreatment device, characterized by, The control method is used for controlling the exhaust gas aftertreatment device according to any one of claims 1 to 6, and comprises the following steps: obtaining starting information of the vehicle; According to the start information, it is determined that the vehicle is in a cold start working condition, and the first three-way valve (4) and the second three-way valve (7) of the vehicle are controlled to be opened, so that the tail gas of the vehicle passes through the flow catalyst component (2) and the particle trap (3), the HC trap (5) and the NO X trap (6) in sequence. obtaining the inlet temperature of the HC trap (5), when the adsorbent part inlet temperature T1 rises to a difference of less than 10℃ from the pollutant desorption critical temperature T0 of the trapping catalyst, controlling the first three-way valve (4) and the second three-way valve (7) to be in an open conduction state, so that the engine exhaust gas flows to the catalyst part (2) and the particulate trap (3) and then to the muffling unit (18), while the second three-way valve (7) is completely closed; obtaining the exhaust temperature of the vehicle, and controlling the first three-way valve (4) and the second three-way valve (7) to be in an open conduction state, so that the engine exhaust gas flows to the adsorbent part via the coupling catalyst part, and the exhaust gas passing through the adsorbent part is guided to the exhaust gas recirculation pipeline (8).

9. The control method according to claim 8, characterized by, The control method further comprises: obtaining the time required for completing the pollutant desorption; based on the time required for completing the desorption, controlling the first three-way valve (4) and the second three-way valve (7) to be in an open conduction state, so that the first three-way valve (4) guides all the engine exhaust gas to the muffling unit (18).

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