Engine exhaust aftertreatment device and vehicle

Abstract

The invention discloses an engine exhaust aftertreatment device and a vehicle, and relates to the technical field of vehicles. The particle trap is arranged in the exhaust channel and is provided with a carrier wall; in the axial direction of the particle trap, the carrier wall is provided with a first area section, a second area section and a third area section which are sequentially arranged, and the length of the second area section is larger than the sum of the length of the first area section and the length of the third area section. And the loading capacity of the catalyst coating of the second area section is greater than that of the catalyst coating of the first area section and greater than that of the catalyst coating of the third area section. By arranging the first area section, the second area section and the third area section with the axial gradient, the back pressure of the particulate filter can be reduced, oil consumption can be reduced, the output torque of an engine can be improved, and the engine exhaust aftertreatment device can have high filtering efficiency so as to meet the emission regulation requirement of the next generation.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to an engine exhaust after-treatment device and a vehicle having the engine exhaust after-treatment device. Background Art

[0002] In the relevant technology, the particle size distribution of particles emitted by vehicles (including gasoline engines equipped with plug-in hybrid PHEV new energy vehicles) has a recognized bimodal characteristic, and small-size particles composed of volatile condensates account for a high proportion of the number of particles emitted. Therefore, when emission regulations are upgraded and the monitoring range of particle size of emitted particles is expanded from the lower limit of 23nm to 10nm, the particle count will increase significantly.

[0003] Market research shows that in order to meet current European or Chinese regulations, the filtration efficiency (i.e., the amount of particulate matter reduced) of a gasoline particulate filter (GPF) or a gasoline particulate filter (FWC) with a catalyst coating is approximately 60-70% relative to a straight-through three-way catalytic converter.

[0004] In order to meet the next generation of European or Chinese regulations, the filtration efficiency of GPF or FWC relative to the straight-through three-way catalytic converter must be at least 85%. In addition, compared with the equivalent straight-through catalytic converter, the back pressure of FWC will increase, resulting in excessive fuel consumption of the vehicle. Therefore, a particle filter with low back pressure increase and high filtration efficiency is urgently needed. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one purpose of the present invention is to provide an engine exhaust aftertreatment device that can reduce the back pressure of the particulate trap and improve the filtering efficiency of the particulate trap, thereby improving the working efficiency of the engine exhaust aftertreatment device.

[0006] The present invention further provides a vehicle.

[0007] According to an embodiment of the present invention, an engine exhaust aftertreatment device comprises: an exhaust line, the exhaust line is formed with an exhaust channel, the exhaust line has an air inlet and an air outlet, and the exhaust channel connects the air inlet and the air outlet; a particulate trap, the particulate trap is arranged in the exhaust channel, the particulate trap is formed with an inlet channel and an outlet channel, the inlet channel and the outlet channel are arranged along the radial direction of the particulate trap, and the inlet channel and the outlet channel both extend along the axial direction of the particulate trap, the particulate trap has a carrier wall, the carrier wall is located between adjacent inlet channels and outlet channels, the carrier wall is formed with a plurality of through holes, the through holes connect the inlet channels and the outlet channels, and a catalyst coating is provided on the surface of the carrier wall and / or the inner wall of the through holes; along the axial direction of the particulate trap, the carrier wall has a first area section, a second area section and a third area section, the second area section is located between the first area section and the third area section, the length of the second area section is greater than the sum of the length of the first area section and the length of the third area section, and the catalyst coating loading of the second area section is greater than the catalyst coating loading of the first area section, and the catalyst coating loading of the second area section is greater than the catalyst coating loading of the third area section.

[0008] According to the engine exhaust after-treatment device of the embodiment of the present invention, by setting the first area segment, the second area segment and the third area segment with axial gradient, the back pressure of the particulate collector can be reduced (≤55mbar), which is beneficial to reducing fuel consumption and improving the output torque of the engine. It can also make the engine exhaust after-treatment device have a higher filtration efficiency (≥85%) to meet the requirements of the next generation of emission regulations, thereby improving the working efficiency of the engine exhaust after-treatment device.

[0009] In some embodiments of the present invention, the catalyst coating loading of the second zone segment is greater than or equal to the sum of the catalyst coating loading of the first zone segment and the catalyst coating loading of the third zone segment.

[0010] In some embodiments of the present invention, the catalyst coating loading of the first zone section is different from the catalyst coating loading of the third zone section.

[0011] In some embodiments of the present invention, the average value of the catalyst coating loading of the first zone segment, the catalyst coating loading of the second zone segment and the catalyst coating loading of the third zone segment is D, satisfying the relationship: 75g / L≤D<240g / L.

[0012] In some embodiments of the present invention, the catalyst coating loading of the first zone segment is D1, the catalyst coating loading of the second zone segment is D2, and the catalyst coating loading of the third zone segment is D3, satisfying the relationship: 40g / L≤D1<240g / L, 85g / L≤D2<240g / L, 40g / L≤D3<240g / L.

[0013] In some embodiments of the present invention, the length of the first region segment is the same as the length of the third region segment.

[0014] In some embodiments of the present invention, the catalyst coating has a noble metal, and the total noble metal loading of the catalyst coating is A, satisfying the relationship: 1 g / ft 3 ≤A≤150g / ft 3 .

[0015] In some embodiments of the present invention, the porosity of the carrier wall is P, which satisfies the relationship: 45%≤P≤70%.

[0016] In some embodiments of the present invention, an average pore size of the plurality of through holes is greater than or equal to 3 μm and less than or equal to 35 μm.

[0017] In some embodiments of the present invention, along the axial direction of the particle trap, the inlet channel has a first open end, the outlet channel has a second open end, and the first open end and the second open end are respectively located at two ends of the particle trap.

[0018] In some embodiments of the present invention, there are multiple inlet channels and multiple outlet channels, which are alternately arranged along the radial direction of the particle collector. There are multiple carrier walls, and a carrier wall is provided between each adjacent inlet channel and outlet channel.

[0019] In some embodiments of the present invention, the engine exhaust aftertreatment device further includes: a catalytic unit, the catalytic unit is arranged in the exhaust passage, the catalytic unit is located between the particulate trap and the air intake, and the catalytic unit and the particulate trap are spaced apart.

[0020] In some embodiments of the present invention, the engine exhaust after-treatment device further includes: an exhaust gas reflow pipe, the exhaust pipe is formed with a first connecting hole, the first connecting hole is located between the catalytic unit and the particulate collector, and the first connecting hole connects the exhaust gas reflow pipe and the exhaust channel.

[0021] In some embodiments of the present invention, the engine exhaust after-treatment device also includes: an intake pressure difference pipeline, an outlet pressure difference pipeline, a first temperature sensor and a second temperature sensor, the exhaust pipeline is formed with a second connecting hole and a third connecting hole, the second connecting hole is located between the catalytic unit and the particulate collector, the third connecting hole is located on the side of the particulate collector away from the catalytic unit, the second connecting hole connects the intake pressure difference pipeline and the exhaust channel, the third connecting hole connects the outlet pressure difference pipeline and the exhaust channel, the intake pressure difference pipeline and the outlet pressure difference pipeline are both provided with pressure sensors, the first temperature sensor is arranged in the exhaust pipeline and is located between the catalytic unit and the particulate collector, and the second temperature sensor is arranged in the exhaust pipeline and is located on the side of the particulate collector away from the catalytic unit.

[0022] In some embodiments of the present invention, the exhaust pipe has a first pipe section, a second pipe section and a third pipe section, the second pipe section is connected between the first pipe section and the third pipe section, the first pipe section forms an air inlet, the third pipe section forms an air outlet, the particulate collector is arranged in the second pipe section, the first pipe section includes an inner pipe layer, an insulation layer and an outer pipe layer, the outer pipe layer is sleeved on the inner pipe layer, and the insulation layer is arranged between the inner pipe layer and the outer pipe layer.

[0023] A vehicle according to an embodiment of the present invention comprises the engine exhaust after-treatment device of the above embodiment.

[0024] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0026] Figure 1 is a schematic structural diagram of an engine exhaust aftertreatment device according to an embodiment of the present invention;

[0027] Figure 2 is a cross-sectional view of a first pipe section according to an embodiment of the present invention;

[0028] Figure 3 is a cross-sectional view of a particle trap according to an embodiment of the present invention.

[0029] Reference numerals:

[0030] An engine exhaust aftertreatment device 100;

[0031] Exhaust pipeline 1; exhaust channel 11; air inlet 12;

[0032] First pipe section 14; inner pipe layer 141; insulation layer 142; outer pipe layer 143;

[0033] The second pipe section 15; the third pipe section 16;

[0034] Particle collector 2; inlet channel 21; first open end 211; outlet channel 22; second open end 221;

[0035] Carrier wall 23; first region 231; second region 232; third region 233;

[0036] Catalyst coating 24;

[0037] Catalytic unit 3;

[0038] Exhaust gas reflow pipeline 4; exhaust gas reflow device 41;

[0039] Intake pressure differential pipeline 5;

[0040] Outlet pressure difference pipeline 6;

[0041] Bellows 7;

[0042] Exhaust line with hump pipe8. DETAILED DESCRIPTION

[0043] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0044] Reference below Figure 1-Figure 3 An engine exhaust aftertreatment device 100 according to an embodiment of the present invention is described.

[0045] like Figure 1 and Figure 3 As shown, the engine exhaust aftertreatment device 100 according to the embodiment of the present invention includes: an exhaust pipe 1, the exhaust pipe 1 is formed with an exhaust channel 11, the exhaust pipe 1 has an air inlet 12 and an air outlet, and the exhaust channel 11 communicates with the air inlet 12 and the air outlet; a particulate collector 2, the particulate collector 2 is arranged in the exhaust channel 11, the particulate collector 2 is formed with an inlet channel 21 and an outlet channel 22, the inlet channel 21 and the outlet channel 22 are arranged along the radial direction of the particulate collector 2, and the inlet channel 21 and the outlet channel 22 both extend along the axial direction of the particulate collector 2, the particulate collector 2 has a carrier wall 23, the carrier wall 23 is located between adjacent inlet channels 21 and outlet channels 22, the carrier wall 23 is formed with a plurality of through holes, and the through holes The inlet channel 21 and the outlet channel 22 are connected, and the surface of the carrier wall 23 and / or the inner wall of the through hole are provided with a catalyst coating 24; along the axial direction of the particulate collector 2, the carrier wall 23 has a first area segment 231, a second area segment 232 and a third area segment 233, the second area segment 232 is located between the first area segment 231 and the third area segment 233, the length of the second area segment 232 is greater than the sum of the length of the first area segment 231 and the length of the third area segment 233, and the loading amount of the catalyst coating 24 of the second area segment 232 is greater than the loading amount of the catalyst coating 24 of the first area segment 231, and the loading amount of the catalyst coating 24 of the second area segment 232 is greater than the loading amount of the catalyst coating 24 of the third area segment 233.

[0046] The vehicle generates exhaust gas during driving, and the exhaust gas can flow into the exhaust pipe 1 from the air inlet 12 of the exhaust pipe 1, and be discharged through the air outlet after being filtered in the exhaust pipe 1. The particulate collector 2 is arranged in the exhaust passage 11, so that the particulate collector 2 can effectively reduce the emission of particulate matter. The inlet channel 21 and the outlet channel 22 of the particulate collector 2 are arranged along the radial direction of the particulate collector 2, and the inlet channel 21 and the outlet channel 22 are both arranged along the axial extension of the particulate collector 2.

[0047] The particulate collector 2 has a carrier wall 23. As some embodiments of the present application, the carrier wall 23 can be constructed as a metal carrier. As some embodiments of the present application, the carrier wall 23 can be constructed as a ceramic carrier, for example: silicon carbide, cordierite, aluminum nitride, silicon nitride, aluminum titanate, aluminum oxide, etc., or a composite material containing any two or more of these materials. Further, a carrier wall 23 is provided between adjacent inlet channels 21 and outlet channels 22, and along the arrangement direction of the inlet channels 21 and the outlet channels 22, the carrier wall 23 is formed with a plurality of through holes (the through holes can be constructed as smaller pores, not shown in the figure), that is, the through holes connect the inlet channels 21 and the outlet channels 22, so that the exhaust gas can flow from the inlet channel 21 into the outlet channel 22 through the through holes, thereby achieving the effect of smooth discharge of the exhaust gas from the particulate collector 2.

[0048] As some embodiments of the present application, the surface of the carrier wall 23 is provided with a catalyst coating 24. As some embodiments of the present application, the inner wall of the through hole is provided with a catalyst coating 24. As some embodiments of the present application, the surface of the carrier wall 23 and the inner wall of the through hole are both provided with a catalyst coating 24. The catalyst coating 24 may contain a platinum group metal (e.g., platinum, palladium, rhodium), a high specific surface area oxide substrate (e.g., alumina) and an oxygen storage material (oxygen storage component, such as cerium-zirconium oxide). By providing a catalyst coating 24 on the surface of the carrier wall 23, particulate matter in the exhaust gas discharged by the internal combustion engine can be effectively filtered. It should be noted that the pore portion of the carrier wall 23 containing the catalyst coating 24 is defined by the space between the particles in the catalyst coating 24.

[0049] As some embodiments of the present application, the method for setting the catalyst coating 24 is: introducing a combustible substance (i.e., a polymer) into the carrier wall 23, coating a layer of catalyst coating 24 on the carrier wall 23 including the polymer and drying it, and then calcining the catalyst coating 24 and the carrier wall 23 to burn off the polymer.

[0050] Along the axial direction of the particle trap 2, the carrier wall 23 has a first region 231, a second region 232 and a third region 233, and the sum of the length of the first region 231, the length of the second region 232 and the length of the third region 233 is the axial length of the carrier wall 23 along the particle trap 2. The second region 232 is located between the first region 231 and the third region 233, that is, along the axial direction of the particle trap 2, the first region 231, the second region 232 and the third region 233 are arranged in sequence. The length of the second region 232 is greater than the sum of the length of the first region 231 and the length of the third region 233, and the loading amount of the catalyst coating 24 of the second region 232 (the mass of the dry weight of the catalyst coating 24 per unit volume in the region) is greater than the loading amount of the catalyst coating 24 of the first region 231, and the loading amount of the catalyst coating 24 of the second region 232 is greater than the loading amount of the catalyst coating 24 of the third region 233.

[0051] It should be noted that the length of the first area section 231 and the length of the second area section 232 are not zero. By setting the first area section 231, the second area section 232 and the third area section 233 that satisfy the above relationship, the engine exhaust after-treatment device 100 can meet the development requirements, that is, the particulate trap 2 simultaneously meets the requirements of lower back pressure (≤55mbar) and higher filtration efficiency (≥85%) to meet the requirements of the next generation of emission regulations.

[0052] Specifically, by setting different coating amounts of the catalyst coating 24 on the particulate trap 2, the test results are compared.

[0053] Example 1: This example is used to illustrate a general method for preparing a particle trap 2 having different axial gradients of the amount of catalyst coating 24. The size of the particle trap 2 is 118.4 mm (diameter) and 127 mm (height), the mesh number of the carrier wall 23 is 300 mesh, and the thickness of the carrier wall 23 is 0.008 inches.

[0054] The typical slurry preparation process of the catalyst coating 24 is as follows: 52 mass units of γ-alumina and 52 mass units of cerium-zirconium oxygen storage material (including 21 mass units of cerium oxide, 26 mass units of zirconium oxide, 2.5 mass units of lanthanum oxide and 2.5 mass units of yttrium oxide) are weighed, and an appropriate amount of deionized water is added to make a suspension. An aqueous solution of a platinum group metal active center precursor (palladium nitrate and rhodium nitrate) is added to the above suspension, wherein the total amount of the noble metal precursor (in terms of the mass of the noble metal palladium and rhodium) is 0.15 mass units, and the ratio of palladium to rhodium (in terms of mass) is 1:1. The pH of the suspension is adjusted to 5.5 with glacial acetic acid, and a slurry is prepared by ball milling. The particle size distribution of the slurry is D50 of 2.6 microns and D90 of 13 microns. This is a platinum group metal catalyst slurry. The same slurry will be used for the preparation of the following embodiments and comparative embodiments.

[0055] Typical slurry coating procedure for catalyst coating 24: adjust the above-mentioned platinum group metal catalyst slurry to a suitable solid content, then take the carrier wall 23 of the particulate collector 2, place it under the coating fixture, and use vacuum suction and air blowing to evenly coat the slurry on the target length of the carrier wall 23 from one end face, and place the slurry-coated carrier wall 23 at 180°C for 1 hour, and then bake it at 450°C for 2 hours. If multiple coatings are required, the baked carrier wall 23 can be cooled to room temperature, and then the subsequent catalyst coating 24 can be applied. Each coating requires the same drying and baking steps until the target coating style of the particulate collector 2 is completed, that is, the particulate collector 2 coated with the catalyst coating 24 is obtained. It should be noted that the coating load area can be qualitatively determined by X-ray photographs, and can also be quantitatively determined by weighing each partition in the carrier wall 23.

[0056] Comparative Example 2:

[0057] The support wall 23 of the particle trap 2 is a blank support wall 23 without the catalyst coating 24 .

[0058] Comparative Example 3:

[0059] The support wall 23 of the particle trap 2 is a support wall 23 uniformly coated with a catalyst-containing coating layer 24 .

[0060] According to the coating procedure described in Example 1, coating is performed from the second open end 221, the coating length is 100% of the total length of the carrier, that is, 127 mm, and the coating amount of the finished catalyst coating 24 is 75 g / L. In this embodiment, the first zone 231 is 127 mm.

[0061] Embodiment 4:

[0062] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0063] According to the coating procedure described in Example 1, the first coating was performed from the second open end 221, the coating length was 54% of the total length of the carrier, i.e., 68.5 mm, and the coating amount of the catalyst coating 24 in the first coating was 69.4 g / L. After drying and sintering, the second coating was performed from the first open end 211, the coating length was 54% of the total length of the carrier, i.e., 68.5 mm, and the coating amount of the catalyst coating 24 in the second coating was 69.4 g / L.

[0064] In this embodiment, the first coating and the second coating have a repeating area, which is the length of the second area segment 232. The length of the second area segment 232 = the length of the first coating + the length of the second coating - the length of the carrier wall 23, that is, the length of the second area segment 232 = 68.5mm + 68.5mm - 127mm = 10mm. The length of the first area segment 231 = the length of the second coating - the length of the second area segment 232, that is, the length of the first area segment 231 = 68.5mm - 10mm = 58.5mm. The length of the third area segment 233 = the length of the first coating - the length of the second area segment 232, that is, the length of the third area segment 233 = 68.5mm - 10mm = 58.5mm.

[0065] The coating amount of the first section 231 is the coating amount of the second coating of the catalyst coating 24, that is, 69.4 g / L. The coating amount of the second section 232 is the sum of the coating amount of the first coating of the catalyst coating 24 and the coating amount of the second coating of the catalyst coating 24, that is, 138 g / L. The coating amount of the third section 233 is the coating amount of the first coating of the catalyst coating 24, that is, 69.4 g / L.

[0066] The following examples all use this sum-and-subtraction method to respectively determine the length of the first area segment 231, the length of the second area segment 232, and the length of the third area segment 233, as well as the coating amount of the first area segment 231, the coating amount of the second area segment 232, and the coating amount of the third area segment 233, which are all organized in Table 1, and the calculation process will not be repeated here.

[0067] Embodiment five:

[0068] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0069] According to the coating procedure described in Example 1, the first coating is performed from the second open end 221, the coating length is 62% of the total length of the carrier, that is, 78.7 mm, and the first coating catalyst coating amount is 60.5 g / L. After drying and sintering, the second coating is performed from the first open end 211, the coating length is 62% of the total length of the carrier, that is, 78.7 mm, and the second coating catalyst coating amount is 60.5 g / L.

[0070] Embodiment six:

[0071] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0072] According to the coating procedure described in Example 1, the first coating is performed from the second open end 221, the coating length is 75% of the total length of the carrier, that is, 95.2 mm, and the first coating catalyst coating amount is 50 g / L. After drying and sintering, the second coating is performed from the first open end 211, the coating length is 75% of the total length of the carrier, that is, 95.2 mm, and the second coating catalyst coating amount is 50 g / L.

[0073] Embodiment seven:

[0074] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0075] According to the coating procedure described in Example 1, the first coating was performed from the second open end 221, the coating length was 88% of the total length of the carrier, i.e., 111.8 mm, and the first coating catalyst coating amount was 42.6 g / L. After drying and sintering, the second coating was performed from the first open end 211, the coating length was 88% of the total length of the carrier, i.e., 111.8 mm, and the second coating catalyst coating amount was 42.6 g / L.

[0076] Comparative Example 8:

[0077] The support wall 23 of the particulate trap 2 is a support wall 23 uniformly coated with a catalyst coating 24 .

[0078] According to the coating procedure described in Example 1, the first coating is performed from the first open end 211, the coating length is 100% of the total length of the carrier, that is, 127 mm, and the first coating catalyst coating amount is 37.5 g / L. After drying and sintering, the second coating is performed from the first open end 211, the coating length is 100% of the total length of the carrier, that is, 127 mm, and the second coating catalyst coating amount is 37.5 g / L.

[0079] Embodiment nine:

[0080] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0081] According to the coating procedure described in Example 1, the first coating was performed from the second open end 221, the coating length was 88% of the total length of the carrier, i.e., 111.8 mm, and the first coating catalyst coating amount was 42.6 g / L. After drying and sintering, the second coating was performed from the first open end 211, the coating length was 75% of the total length of the carrier, i.e., 95.2 mm, and the second coating catalyst coating amount was 50 g / L.

[0082] Embodiment ten:

[0083] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0084] According to the coating procedure described in Example 1, the first coating was performed from the second open end 221, the coating length was 75% of the total length of the carrier, i.e., 95.2 mm, and the first coating catalyst coating amount was 50 g / L. After drying and sintering, the second coating was performed from the first open end 211, the coating length was 88% of the total length of the carrier, i.e., 111.8 mm, and the second coating catalyst coating amount was 42.6 g / L.

[0085] Embodiment eleven:

[0086] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0087] According to the coating procedure described in Example 1, the first coating is performed from the second open end 221, the coating length is 100% of the total length of the carrier, that is, 127 mm, and the first coating catalyst coating amount is 20 g / L. After drying and sintering, the second coating is performed from the second open end 221, the coating length is 33% of the total length of the carrier, that is, 41.9 mm, and the second coating catalyst coating amount is 83.3 g / L. After drying and sintering, the third coating is performed from the first open end 211, the coating length is 33% of the total length of the carrier, that is, 41.9 mm, and the third coating catalyst coating amount is 83.3 g / L.

[0088] Embodiment 12:

[0089] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0090] According to the coating procedure described in Example 1, the first coating is performed from the second open end 221, the coating length is 100% of the total length of the carrier, that is, 127 mm, and the first coating catalyst coating amount is 50 g / L. After drying and sintering, the second coating is performed from the first open end 211, the coating length is 50% of the total length of the carrier, that is, 63.5 mm, and the second coating catalyst coating amount is 50 g / L.

[0091] Embodiment 13:

[0092] The support wall 23 of the particulate trap 2 is a support wall 23 having a catalyst coating amount gradient in the axial direction.

[0093] According to the coating procedure described in Example 1, the first coating is performed from the second open end 221, the coating length is 50% of the total length of the carrier, that is, 63.5 mm, and the first coating catalyst coating amount is 50 g / L. After drying and sintering, the second coating is performed from the first open end 211, the coating length is 100% of the total length of the carrier, that is, 127 mm, and the second coating catalyst coating amount is 50 g / L.

[0094] The coating distribution of the above embodiments and comparative embodiments is shown in Table 1:

[0095]

[0096] Table 1

[0097] Embodiment 14:

[0098] This embodiment is used to illustrate the testing methods and results of the particle collector 2 embodiment of the present invention and the comparative embodiment.

[0099] The back pressure tests of Comparative Example 2, Comparative Example 3, Examples 4 to 7, Comparative Example 8, and Examples 9 to 13 were conducted at 23 degrees Celsius. The back pressure test equipment is carried out and the measurement and recording are carried out at 600m 3 / h air flow rate of the particle collector 2.

[0100] The evaluation of the filtration efficiency of Comparative Example 2, Comparative Example 3, Examples 4 to 7, Comparative Example 8, and Examples 9 to 13 was conducted on an engine bench, and the engine bench was equipped with a 1.5LT-GDI engine of a certain brand as a test engine. The test cycle was a WLTC cycle condition, and the particulate filter 2 to be tested was installed in a tight coupling position behind the engine through a simple straight-tube package. Each simple package of the particulate filter 2 was subjected to three WLTC cycle tests, and the PN before and after the particulate filter 2 was recorded using an AVL489 particle counter. 10 Emissions PN 10,前 and PN 10,后 , calculate the filtration efficiency of particle collector 2 for particles larger than 10 nm according to the following formula:

[0101] Single filtration efficiency FE = 1-PN 10后 / PN 10前 ×100%

[0102] Average filtration efficiency

[0103] The test results of the cold flow back pressure and average filtration efficiency of the above embodiments and comparative embodiments are shown in Table 2:

[0104] serial number Cold flow back pressure / mbar Average filtration efficiency / % Comparative Example 2 47.0 82 Comparative Example 3 54.1 76 Embodiment 4 57.0 74 Embodiment 5 52.3 71 Embodiment 6 50.9 79 Embodiment 7 53.5 88 Comparative Example 8 66.2 88 Embodiment 9 51.2 85 Embodiment 10 52.4 87 Embodiment 11 65.8 80 Embodiment 12 65.8 74 Embodiment 13 62.2 72

[0105] Table 2

[0106] It can be seen from the above experimental results that the lengths of the three regions and the amount of catalyst coating in each region are two main parameters that affect the back pressure and filtration efficiency of the particle trap 2. The particle trap 2 having both high filtration efficiency (≥85%) and low back pressure (≤55 mbar), such as the seventh embodiment, the ninth embodiment and the tenth embodiment, has a second region length greater than the length of the first region 231 + the length of the third region 233, and a catalyst coating 24 loading amount of the second region 232 ≥ the catalyst coating 24 loading amount of the first region 231 + the catalyst coating 24 loading amount of the third region 233.

[0107] Therefore, by setting the first area segment 231, the second area segment 232 and the third area segment 233 with axial gradients, the particulate collector 2 can have a lower back pressure (≤55mbar), which is beneficial to reducing fuel consumption and improving the output torque of the engine. It can also effectively reduce exhaust pollutants CO, HC, NOx, PN, PM while making the engine exhaust after-treatment device 100 have a higher filtration efficiency (≥85%) to meet the requirements of the next generation of emission regulations.

[0108] In some embodiments of the present invention, Figure 3 As shown, the loading amount of the catalyst coating 24 in the second section 232 is equal to the sum of the loading amount of the catalyst coating 24 in the first section 231 and the loading amount of the catalyst coating 24 in the third section 233 .

[0109] Among them, in Example 4 to Example 7 and Example 9 to Example 10 in Table 1, the loading amount of the catalyst coating 24 in the second area segment 232 is greater than or equal to the sum of the loading amount of the catalyst coating 24 in the first area segment 231 and the loading amount of the catalyst coating 24 in the third area segment 233. Such a setting facilitates the control of the loading amount of the catalyst coating 24, which is beneficial to improving the loading amount accuracy of the first area segment 231, the second area segment 232 and the third area segment 233, thereby improving the calculation accuracy of the back pressure and the filtration efficiency.

[0110] Specifically, along the axial direction of the particle collector 2, the particle collector 2 has a first open end 211 and a second open end 221. It should be noted that, along the flow direction of the exhaust gas, the upstream of the carrier wall 23 is the first open end 211, the downstream of the carrier wall 23 is the second open end 221, and the first area section 231 is upstream of the third area section 233. The first catalyst coating 24 is applied from the second open end 221, and the second catalyst coating 24 is applied from the first open end 211 after drying and sintering. If the sum of the length of the first coating and the length of the second coating is greater than the total length of the carrier wall 23, there is an overlapping portion between the first coating and the second coating, and the overlapping portion is the second area section 232. The coating amount of the second area section 232 is the sum of the coating amount of the catalyst coating 24 of the first coating and the coating amount of the catalyst coating 24 of the second coating, that is, the loading amount of the catalyst coating 24 of the second area section 232 is greater than or equal to the sum of the loading amount of the catalyst coating 24 of the first area section 231 and the loading amount of the catalyst coating 24 of the third area section 233.

[0111] In some embodiments of the present invention, Figure 3 As shown, the loading amount of the catalyst coating 24 in the first section 231 is different from the loading amount of the catalyst coating 24 in the third section 233 .

[0112] Among them, if the coating amount of the first catalyst coating 24 from the second open end 221 is different from the coating amount of the second catalyst coating 24 from the first open end 211 after drying and sintering, the loading amount of the catalyst coating 24 in the first area segment 231 and the loading amount of the catalyst coating 24 in the third area segment 233 are different. Such a setting can increase the types and number of embodiments of the particulate collector 2 test method experiment, which is beneficial to conduct a variety of different parameter experiments on the particulate collector 2, thereby improving the accuracy and reliability of the experimental results.

[0113] In some embodiments of the present invention, Figure 3 As shown, the average value of the catalyst coating 24 loading amount of the first zone segment 231, the catalyst coating 24 loading amount of the second zone segment 232 and the catalyst coating 24 loading amount of the third zone segment 233 is D, satisfying the relationship: 75g / L≤D<240g / L.

[0114] Among them, the average value D of the catalyst coating 24 loading amount of the first area segment 231, the catalyst coating 24 loading amount of the second area segment 232 and the catalyst coating 24 loading amount of the third area segment 233 satisfies the relationship: 75g / L≤D<240g / L, that is, the average value of the catalyst coating 24 loading amount of the first area segment 231, the catalyst coating 24 loading amount of the second area segment 232 and the catalyst coating 24 loading amount of the third area segment 233 is between 75g / L and 240g / L, and the average value D of the catalyst coating 24 loading amount of the first area segment 231, the catalyst coating 24 loading amount of the second area segment 232 and the catalyst coating 24 loading amount of the third area segment 233 can be 75g / L, 100g / L, 150g / L, 240g / L and other values. Such a setting can make the average value of the catalyst coating 24 loading amount of the first area segment 231, the catalyst coating 24 loading amount of the second area segment 232 and the catalyst coating 24 loading amount of the third area segment 233 set reasonably, reduce the risk of insufficient exhaust gas filtration caused by the average value of the catalyst coating 24 loading amount of the first area segment 231, the catalyst coating 24 loading amount of the second area segment 232 and the catalyst coating 24 loading amount of the third area segment 233 being too small, and can also reduce the risk of increased back pressure or increased production cost caused by the average value of the catalyst coating 24 loading amount of the first area segment 231, the catalyst coating 24 loading amount of the second area segment 232 and the catalyst coating 24 loading amount of the third area segment 233 being too large.

[0115] In some embodiments of the present invention, Figure 3 As shown, the loading amount of the catalyst coating 24 in the first area segment 231 is D1, the loading amount of the catalyst coating 24 in the second area segment 232 is D2, and the loading amount of the catalyst coating 24 in the third area segment 233 is D3, satisfying the relationship: 40g / L≤D1<240g / L, 85g / L≤D2<240g / L, 40g / L≤D3<240g / L.

[0116] Among them, the loading amount D1 of the catalyst coating 24 through the first area segment 231 satisfies the relationship: 40g / L≤D1<240g / L, for example: the loading amount D1 of the catalyst coating 24 of the first area segment 231 can be 40g / L, 60g / L, 239g / L and other values, the loading amount D2 of the catalyst coating 24 of the second area segment 232 satisfies the relationship: 85g / L≤D2<240g / L, the loading amount D2 of the catalyst coating 24 of the second area segment 232 can be 85g / L, 90g / L, 239g / L, the loading amount D3 of the catalyst coating 24 of the third area segment 233 satisfies the relationship: 40g / L≤D3<240g / L, the loading amount D3 of the catalyst coating 24 of the third area segment 233 can be Values ​​such as 40g / L, 60g / L, and 239g / L can make the catalyst coating 24 loadings of the first section 231, the second section 232, and the third section 233 all set reasonably, which is beneficial to reducing the risk of insufficient exhaust gas filtration caused by too small loadings of the catalyst coating 24 in the first section 231, the second section 232, and the third section 233, and can also reduce the risk of increased back pressure or increased production costs caused by too large loadings of the catalyst coating 24 in the first section 231, the second section 232, and the third section 233.

[0117] In some embodiments of the present invention, Figure 3 As shown, the length of the first region 231 is the same as the length of the third region 233 .

[0118] Among them, in Example 4 to Example 7 and Example 11 to Example 13 in Table 1, the length of the first coating of the catalyst coating 24 is the same as the length of the second coating of the catalyst coating 24, then the length of the first area segment 231 and the length of the third area segment 233 are both equal to the difference between the length of the coated catalyst coating 24 and the length of the second area segment 232, that is, the length of the first area segment 231 and the length of the third area segment 233 are the same. Such a setting facilitates accurate control of the length of the catalyst coating 24 of the first area segment 231, the length of the catalyst coating 24 of the second area segment 232, and the length of the catalyst coating 24 of the third area segment 233, which is beneficial to improve the length accuracy of the first area segment 231, the second area segment 232 and the third area segment 233, thereby improving the calculation accuracy of the back pressure and filtration efficiency of the particulate collector 2.

[0119] In some embodiments of the present invention, Figure 3 As shown, the catalyst coating 24 has precious metals, and the total precious metal loading of the catalyst coating 24 is A, which satisfies the relationship: 1 g / ft 3≤A≤150g / ft 3 .

[0120] The catalyst coating 24 has a precious metal. As some embodiments of the present application, the precious metal may be a platinum group metal such as platinum, rhodium, palladium, and the total precious metal loading A of the catalyst coating 24 satisfies the relationship: 1 g / ft 3 ≤A≤150g / ft 3 That is, the total precious metal loading A of the catalyst coating 24 is 1 g / ft 3 Up to 150g / ft 3 As some embodiments of the present application, the total precious metal loading A of the catalyst coating 24 may be more preferably in the range of 1.5 g / ft 3 ≤A≤50g / ft 3 Furthermore, the optimal range of the total precious metal loading A of the catalyst coating 24 may be 2 g / ft 3 ≤A≤20g / ft 3 The total precious metal loading A of the catalyst coating 24 may be 1 g / ft 3 , 2g / ft 3 , 150g / ft 3 Such a setting can reduce the risk of insufficient exhaust gas filtration due to too low a total precious metal loading A of the catalyst coating 24, and can also reduce the risk of increased production costs due to too high a total precious metal loading A of the catalyst coating 24, which is conducive to the low-cost design of the engine exhaust after-treatment device 100.

[0121] In some embodiments of the present invention, Figure 3 As shown, the porosity of the carrier wall 23 is P, which satisfies the relationship: 45%≤P≤70%.

[0122] Among them, the porosity is a measure of the percentage of void space in the carrier wall 23, and is related to the back pressure of the engine exhaust aftertreatment device 100. The lower the porosity, the higher the back pressure. The porosity P of the carrier wall 23 satisfies the relationship: 45%≤P≤70%, that is, the porosity P of the carrier wall 23 is between 45% and 70%, and the porosity P of the carrier wall 23 can be 45%, 50%, 60%, 70%, etc. Such a setting can make the porosity of the carrier wall 23 reasonably set, reduce the risk of excessive back pressure caused by too low porosity of the carrier wall 23, and can also reduce the risk of insufficient exhaust gas filtration caused by too high porosity of the carrier wall 23.

[0123] In some embodiments of the present invention, Figure 3 As shown, the average pore size of the plurality of through holes is greater than or equal to 3 μm and less than or equal to 35 μm.

[0124] Among them, the average pore size of the plurality of through holes is greater than or equal to 3μm and less than or equal to 35μm, that is, the average pore size of the plurality of through holes is between 3μm and 35μm. As a more preferred embodiment of the present application, the average pore size of the plurality of through holes is between 10μm and 25μm, and the average pore size of the plurality of through holes can be 3μm, 5μm, 35μm, etc. Such a setting can make the average pore size of the plurality of through holes reasonably set, reduce the risk of excessive back pressure caused by too small average pore size of the carrier wall 23, and can also reduce the risk of insufficient exhaust gas filtration caused by too large average pore size of the carrier wall 23.

[0125] In some embodiments of the present invention, Figure 3 As shown, along the axial direction of the particle trap 2 , the inlet channel 21 has a first open end 211 , and the outlet channel 22 has a second open end 221 . The first open end 211 and the second open end 221 are located at two ends of the particle trap 2 , respectively.

[0126] Among them, along the axial direction of the particle collector 2, that is, the flow direction of the exhaust gas, the inlet channel 21 has a first open end 211, and the exhaust gas can flow into the inlet channel 21 through the first open end 211. The outlet channel 22 has a second open end 221, and the exhaust gas can flow out of the outlet channel 22 through the second open end 221. The first open end 211 and the second open end 221 are respectively located at two ends of the particle collector 2. It should be noted that the first open end 211 is located upstream of the second open end 221. Such a setting can make the arrangement of the first open end 211 and the second open end 221 consistent with the flow direction of the exhaust gas, which is conducive to the exhaust gas flowing from the first open end 211 into the inlet channel 21, filtering through the through holes of the carrier wall 23 and flowing into the outlet channel 22, and then flowing out of the outlet channel 22 through the second open end 221, so as to achieve a smooth filtering and discharge effect of the exhaust gas.

[0127] In some embodiments of the present invention, Figure 3 As shown, there are multiple inlet channels 21 and multiple outlet channels 22, which are alternately arranged along the radial direction of the particle collector 2, and there are multiple carrier walls 23, with a carrier wall 23 provided between each adjacent inlet channel 21 and outlet channel 22.

[0128] Among them, there are multiple inlet channels 21 and outlet channels 22. As some embodiments of the present application, there are five inlet channels 21 and five outlet channels 22. As some embodiments of the present application, there are six inlet channels 21 and six outlet channels 22. Multiple inlet channels 21 and multiple outlet channels 22 are alternately arranged along the radial direction of the particulate collector 2, that is, one inlet channel 21 and one outlet channel 22 are arranged in sequence. There are multiple carrier walls 23, and a carrier wall 23 is provided between each adjacent inlet channel 21 and outlet channel 22, so that the exhaust gas flowing into the inlet channel 21 can be filtered through the through holes of the carrier wall 23 and flow into the outlet channel 22, and then flow out of the outlet channel 22 through the second open end 221, so as to achieve the smooth filtering and discharge effect of the exhaust gas.

[0129] In some embodiments of the present invention, Figure 1 As shown, the engine exhaust aftertreatment device 100 may further include: a catalytic unit 3, which is disposed in the exhaust passage 11, between the particulate trap 2 and the air intake 12, and the catalytic unit 3 and the particulate trap 2 are spaced apart.

[0130] Among them, as some embodiments of the present application, the catalytic unit 3 can be constructed as a three-way catalytic converter. The catalytic unit 3 is arranged in the exhaust passage 11, and the catalytic unit 3 is located between the particulate trap 2 and the air inlet 12, that is, along the flow direction of the exhaust gas, the catalytic unit 3 is located downstream of the air inlet 12 and upstream of the particulate trap 2. The catalytic unit 3 and the particulate trap 2 can respectively perform oxidation-reduction treatment on the gaseous pollutants CO, HC, and NOx in the exhaust gas and perform oxidation combustion purification treatment on the particulate matter PN and PM.

[0131] The catalytic unit 3 and the particulate trap 2 are spaced apart. As some embodiments of the present application, the catalytic unit 3 and the particulate trap 2 are integrated into an exhaust pipe 1, and the exhaust pipe 1 forms an exhaust channel 11, so that the catalytic unit 3 and the particulate trap 2 are constructed as a tightly coupled catalyst, and the catalytic unit 3 and the particulate trap 2 are connected and arranged, which is beneficial to improving the integration of the engine exhaust after-treatment device 100, and is also beneficial to the exhaust gas being smoothly processed in the engine exhaust after-treatment device 100 and discharged from the engine exhaust after-treatment device 100.

[0132] In some embodiments of the present invention, Figure 1 As shown, the engine exhaust aftertreatment device 100 may further include: an exhaust gas reflow pipe 4, the exhaust pipe 1 is formed with a first connecting hole, the first connecting hole is located between the catalytic unit 3 and the particulate trap 2, and the first connecting hole connects the exhaust gas reflow pipe 4 and the exhaust channel 11.

[0133] The first connecting hole is located between the catalytic unit 3 and the particulate trap 2, that is, along the flow direction of the gas, the first connecting hole is located downstream of the catalytic unit 3 and upstream of the particulate trap 2. The exhaust gas return pipe 4 and the exhaust pipe 1 can be connected by welding, but not limited to, so that the first connecting hole connects the exhaust gas return pipe 4 and the exhaust channel 11, and the exhaust gas return pipe 4 can be connected to the exhaust gas return device 41 by a flange, so that when the engine is working, the engine exhaust after-treatment device 100 can guide a part of the exhaust gas from the exhaust gas return pipe 4 through the exhaust gas return device 41 back to the intake system, and mix with fresh air, thereby reducing the temperature of the combustion chamber and effectively reducing the emission of NOx. In addition, the exhaust gas return device 41 can reduce the fuel consumption rate, which is beneficial to the energy-saving design of the vehicle.

[0134] In some embodiments of the present invention, Figure 1 As shown, the engine exhaust aftertreatment device 100 may also include: an intake pressure difference pipeline 5, an outlet pressure difference pipeline 6, a first temperature sensor and a second temperature sensor. The exhaust pipeline 1 is formed with a second connecting hole (not shown in the figure) and a third connecting hole (not shown in the figure). The second connecting hole is located between the catalytic unit 3 and the particulate trap 2, and the third connecting hole is located on the side of the particulate trap 2 away from the catalytic unit 3. The second connecting hole connects the intake pressure difference pipeline 5 and the exhaust channel 11, and the third connecting hole connects the outlet pressure difference pipeline 6 and the exhaust channel 11. The intake pressure difference pipeline 5 and the outlet pressure difference pipeline 6 are both provided with pressure sensors (not shown in the figure). The first temperature sensor (not shown in the figure) is arranged in the exhaust pipeline 1 and is located between the catalytic unit 3 and the particulate trap 2. The second temperature sensor (not shown in the figure) is arranged in the exhaust pipeline 1 and is located on the side of the particulate trap 2 away from the catalytic unit 3.

[0135] The second connecting hole is located between the catalytic unit 3 and the particulate trap 2, and the third connecting hole is located on the side of the particulate trap 2 away from the catalytic unit 3, that is, along the flow direction of the exhaust gas, the catalytic unit 3, the second connecting hole, the particulate trap 2 and the third connecting hole are arranged in sequence. The first temperature sensor is arranged in the exhaust pipe 1 and located between the catalytic unit 3 and the particulate trap 2, and the second temperature sensor is arranged in the exhaust pipe 1 and located on the side of the particulate trap 2 away from the catalytic unit 3. That is, along the flow direction of the exhaust gas, the catalytic unit 3, the first temperature sensor, the particulate trap 2 and the second temperature sensor are arranged in sequence.

[0136] The second connecting hole connects the intake pressure difference pipeline 5 and the exhaust channel 11, and the third connecting hole connects the outlet pressure difference pipeline 6 and the exhaust channel 11. The intake pressure difference pipeline 5 and the outlet pressure difference pipeline 6 are both provided with pressure sensors. The pressure sensors of the intake pressure difference pipeline 5 and the outlet pressure difference pipeline 6 respectively detect the pressures upstream and downstream of the particulate trap 2 and make a difference. The first temperature sensor and the second temperature sensor respectively detect the temperatures upstream and downstream of the particulate trap 2 and make a difference. The pressure difference and temperature difference of the particulate trap 2 can be obtained, so as to determine whether the particulate trap 2 should be cleaned or replaced according to the pressure difference, thereby reducing the risk of failure of the engine exhaust after-treatment device 100 due to blockage of the particulate trap 2, which is beneficial to improving the working reliability of the engine exhaust after-treatment device 100.

[0137] In some embodiments of the present invention, Figure 1 and Figure 2 As shown, the exhaust pipe 1 has a first pipe section 14, a second pipe section 15 and a third pipe section 16, the second pipe section 15 is connected between the first pipe section 14 and the third pipe section 16, the first pipe section 14 forms an air inlet 12, the third pipe section 16 forms an air outlet, the particulate collector 2 is arranged in the second pipe section 15, the first pipe section 14 includes an inner pipe layer 141, a thermal insulation layer 142 and an outer pipe layer 143, the outer pipe layer 143 is sleeved on the inner pipe layer 141, and the thermal insulation layer 142 is arranged between the inner pipe layer 141 and the outer pipe layer 143.

[0138] The second pipe section 15 is connected between the first pipe section 14 and the third pipe section 16, that is, along the flow direction of the exhaust gas, the first pipe section 14, the second pipe section 15 and the third pipe section 16 are arranged in sequence. The first pipe section 14 is formed with an air inlet 12, and the exhaust gas flows into the first pipe section 14 through the air inlet 12. The third pipe section 16 is formed with an air outlet (not shown in the figure), and the exhaust gas flows out through the air outlet after being filtered in the engine exhaust after-treatment device 100. The particulate collector 2 is arranged in the second pipe section 15, and the first pipe section 14 includes an inner pipe layer 141, a heat preservation layer 142 and an outer pipe layer 143. The outer pipe layer 143 is sleeved on the inner pipe layer 141, and the heat preservation layer 142 is arranged between the inner pipe layer 141 and the outer pipe layer 143.

[0139] By providing the first pipe section 14 with the insulation layer 142, on the one hand, the first pipe section 14 can have an insulation function, which can effectively improve the problem of reduced exhaust temperature and low pollutant conversion efficiency caused by frequent engine startup of plug-in hybrid vehicles, and through the design of the insulation layer 142, the exhaust temperature can quickly reach the ignition temperature of exhaust pollutants, reduce the ignition time, and improve the pollutant conversion efficiency. On the other hand, the structure also has a heat insulation function, reducing the risk of damage to the exhaust peripheral parts caused by the engine exhaust after-treatment device 100 with too high temperature, thereby reducing the risk of heat damage to the entire vehicle.

[0140] As some embodiments of the present application, Figure 1 As shown, the engine exhaust aftertreatment device 100 may further include a bellows 7 and an exhaust pipe 81. The peripheral wall of the exhaust pipe 81 is formed with a boss structure. By providing the bellows 7, a shock absorbing effect can be achieved. By providing the exhaust pipe 81 with a boss structure, the engine exhaust aftertreatment device 100 can be conveniently connected to subsequent pipes through a clamp without flange connection, thereby effectively reducing the weight of the engine exhaust aftertreatment device 100, which is beneficial to the lightweight design of the vehicle.

[0141] As some embodiments of the present application, in actual use, the typical pore density of the particulate filter 2 is usually 400 mesh per square inch (cpsi) or lower, for example: 200 cpsi, 240 cpsi, 300 cpsi or 360 cpsi, so that relatively large gasoline particulate matter (soot and ash particles) can first enter the inlet channel 21 of the filter without affecting the catalytic unit 3 or the front area of ​​the particulate filter 2, thereby reducing the risk of coking and clogging the channel.

[0142] In actual use, the typical wall thickness of the wall-flow particulate trap 2 is usually 8 mils to 12 mils, such as 8 mils, 8.5 mils, 9 mils, 10 mils or 12 mils, so that the porous filter wall is thick enough to filter most of the particulate matter in the engine exhaust and maintain sufficient mechanical and thermal strength.

[0143] As some embodiments of the present application, in an embodiment, the median size (D50) of the catalyst coating 24 particles is in the range of 1 μm to 20 μm. In practice, the oxygen storage component may have a different particle size than the high specific surface area oxide, such as γ-alumina. Therefore, the D50 of the oxygen storage component may be between 1-8 μm, for example 2-6 μm; while the high specific surface area oxide may have a D50 between 1-12 μm, such as 2-8 μm. In a further embodiment, the D90 of the solid coating particles is in the range of 1 μm to 30 μm. Similarly, the D90 of the oxygen storage component may be different from the D90 of the high surface area oxide. The D50 and D90 measurements are obtained by laser diffraction particle size analysis (a volume-based technique), and a mathematical model is applied to determine the particle size distribution.

[0144] As some embodiments of the present application, the present application also proposes a method for simultaneously converting hydrocarbons, carbon monoxide, nitrogen oxides and filtering and capturing particulate matter in gasoline engine exhaust gas, which method includes the process of filtering exhaust gas by the engine exhaust after-treatment device 100 of the above-mentioned embodiment.

[0145] The vehicle according to the embodiment of the present invention includes the engine exhaust after-treatment device 100 of the above embodiment. By providing the first area section 231, the second area section 232 and the third area section 233 with axial gradients, the particle trap 2 can have a lower back pressure (≤55mbar), which is beneficial to reducing the fuel consumption of the vehicle and improving the output torque of the engine. The engine exhaust after-treatment device 100 can also have a higher filtering efficiency (≥85%) for particulate matter in the particle size range of 10nm to 3μm, so as to meet the requirements of the next generation of emission regulations.

[0146] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0147] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. An engine exhaust aftertreatment device, characterized in that: include: An exhaust pipeline, wherein the exhaust pipeline is formed with an exhaust passage, the exhaust pipeline has an air inlet and an air outlet, and the exhaust passage communicates with the air inlet and the air outlet; A particle trap, the particle trap is arranged in the exhaust passage, the particle trap is formed with an inlet channel and an outlet channel, the inlet channel and the outlet channel are arranged along the radial direction of the particle trap, and the inlet channel and the outlet channel both extend along the axial direction of the particle trap, the particle trap has a carrier wall, the carrier wall is located between adjacent inlet channels and outlet channels, the carrier wall is formed with a plurality of through holes, the through holes communicate with the inlet channel and the outlet channel, and a catalyst coating is provided on a surface of the carrier wall and / or an inner wall of the through hole; Along the axial direction of the particulate collector, the carrier wall has a first region segment, a second region segment and a third region segment, the second region segment is located between the first region segment and the third region segment, the length of the second region segment is greater than the sum of the length of the first region segment and the length of the third region segment, and the catalyst coating loading of the second region segment is greater than the catalyst coating loading of the first region segment, and the catalyst coating loading of the second region segment is greater than the catalyst coating loading of the third region segment.

2. The engine exhaust aftertreatment device according to claim 1, characterized in that: The catalyst coating loading of the second zone segment is greater than or equal to the sum of the catalyst coating loading of the first zone segment and the catalyst coating loading of the third zone segment.

3. The engine exhaust aftertreatment device according to claim 1, characterized in that: The catalyst coating loading amount of the first zone section is different from the catalyst coating loading amount of the third zone section.

4. The engine exhaust aftertreatment device according to claim 1, characterized in that: The average value of the catalyst coating loading of the first zone segment, the catalyst coating loading of the second zone segment and the catalyst coating loading of the third zone segment is D, which satisfies the relationship: 75g / L≤D<240g / L.

5. The engine exhaust aftertreatment device according to claim 4, characterized in that: The catalyst coating loading amount of the first zone segment is D1, the catalyst coating loading amount of the second zone segment is D2, and the catalyst coating loading amount of the third zone segment is D3, satisfying the relationship: 40g / L≤D1<240g / L, 85g / L≤D2<240g / L, 40g / L≤D3<240g / L.

6. The engine exhaust aftertreatment device according to claim 1, characterized in that: The length of the first region segment is the same as the length of the third region segment.

7. The engine exhaust aftertreatment device according to claim 1, characterized in that: The catalyst coating has a noble metal, and the total noble metal loading of the catalyst coating is A, satisfying the relationship: 1 g / ft 3 ≤A≤150g / ft 3 .

8. The engine exhaust aftertreatment device according to claim 1, characterized in that: The porosity of the carrier wall is P, which satisfies the relationship: 45%≤P≤70%.

9. The engine exhaust aftertreatment device according to claim 1, characterized in that: An average pore diameter of the plurality of through holes is greater than or equal to 3 μm and less than or equal to 35 μm.

10. The engine exhaust aftertreatment device according to claim 1, characterized in that: Along the axial direction of the particle trap, the inlet channel has a first open end, and the outlet channel has a second open end, and the first open end and the second open end are respectively located at two ends of the particle trap.

11. The engine exhaust aftertreatment device according to claim 1, characterized in that: There are multiple inlet channels and multiple outlet channels, and the multiple inlet channels and the multiple outlet channels are alternately arranged along the radial direction of the particle collector. There are multiple carrier walls, and the carrier wall is arranged between each adjacent inlet channel and outlet channel.

12. The engine exhaust aftertreatment device according to any one of claims 1 to 11, characterized in that: Also includes: A catalytic unit is disposed in the exhaust passage, the catalytic unit is located between the particle trap and the air inlet, and the catalytic unit and the particle trap are spaced apart.

13. The engine exhaust aftertreatment device according to claim 12, characterized in that: Also includes: An exhaust gas reflow pipeline is formed with a first communication hole, the first communication hole is located between the catalytic unit and the particulate trap, and the first communication hole communicates the exhaust gas reflow pipeline with the exhaust passage.

14. The engine exhaust aftertreatment device according to claim 12, characterized in that: Also includes: An intake pressure difference pipeline, an outlet pressure difference pipeline, a first temperature sensor and a second temperature sensor, the exhaust pipeline is formed with a second connecting hole and a third connecting hole, the second connecting hole is located between the catalytic unit and the particulate trap, the third connecting hole is located on the side of the particulate trap away from the catalytic unit, the second connecting hole connects the intake pressure difference pipeline and the exhaust passage, the third connecting hole connects the outlet pressure difference pipeline and the exhaust passage, the intake pressure difference pipeline and the outlet pressure difference pipeline are both provided with pressure sensors, the first temperature sensor is arranged in the exhaust pipeline and is located between the catalytic unit and the particulate trap, the second temperature sensor is arranged in the exhaust pipeline and is located on the side of the particulate trap away from the catalytic unit.

15. The engine exhaust aftertreatment device according to any one of claims 1 to 11, characterized in that: The exhaust pipe comprises a first pipe section, a second pipe section and a third pipe section, the second pipe section is connected between the first pipe section and the third pipe section, the first pipe section forms the air inlet, the third pipe section forms the air outlet, the particulate collector is arranged in the second pipe section, the first pipe section comprises an inner pipe layer, a thermal insulation layer and an outer pipe layer, the outer pipe layer is sleeved on the inner pipe layer, and the thermal insulation layer is arranged between the inner pipe layer and the outer pipe layer.

16. A vehicle, characterized in that: The invention comprises an engine exhaust after-treatment device according to any one of claims 1 to 15.

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