Engine exhaust aftertreatment device and vehicle

Abstract

The application discloses an engine exhaust aftertreatment device and a vehicle, and relates to the technical field of vehicles, which comprises an exhaust pipeline formed with an exhaust passage; a particle trap is arranged in the exhaust passage and has a carrier wall; along the axial direction of the particle trap, the carrier wall has a first region section, a second region section and a third region section arranged in sequence, the length of the second region section is greater than the sum of the length of the first region section and the length of the third region section, and the catalyst coating load of the second region section is greater than the catalyst coating load of the first region section and greater than the catalyst coating load of the third region section. By arranging the first region section, the second region section and the third region section with axial gradients, the back pressure of the particle trap can be reduced, the fuel consumption can be reduced, the output torque of the engine can be improved, and the engine exhaust aftertreatment device has high filtering efficiency, so as to meet the emission regulation requirements 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] The particle size distribution of particulate matter emitted by vehicles (including plug-in hybrid electric vehicles equipped with gasoline engines) is generally recognized to have a bimodal characteristic, with small particles composed of volatile condensate accounting for a higher proportion of the total number of particles emitted. Therefore, when emission regulations are upgraded and the monitoring range for particle size is expanded from the lower limit of 23nm to 10nm, the particle count will increase significantly.

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

[0004] To meet next-generation European and Chinese regulations, a GPF or FWC must achieve a minimum filtration efficiency of 85% compared to a flow-through three-way catalytic converter. Furthermore, compared to an equivalent flow-through catalytic converter, an FWC generates increased backpressure, resulting in excessive fuel consumption. Therefore, a particulate filter with minimal backpressure 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 object of the present invention is to provide an engine exhaust aftertreatment device that can reduce the back pressure of the particulate filter and improve the filtration efficiency of the particulate filter, thereby improving the operating efficiency of the engine exhaust aftertreatment device.

[0006] The present invention further provides a vehicle.

[0007] An engine exhaust aftertreatment device according to an embodiment of the present invention includes: an exhaust pipe, the exhaust pipe forming an exhaust channel, the exhaust pipe having an air inlet and an air outlet, the exhaust channel communicating with the air inlet and the air outlet; a particulate trap, the particulate trap disposed in the exhaust channel, the particulate trap forming an inlet channel and an outlet channel, the inlet channel and the outlet channel being arranged radially along the particulate trap, and both the inlet channel and the outlet channel extending axially of the particulate trap; the particulate trap having a carrier wall, the carrier wall being located between adjacent inlet channels and outlet channels, the carrier wall being formed with a plurality of through holes communicating with the inlet channels and the outlet channels, a catalyst coating being provided on a surface of the carrier wall and / or an inner wall of the through holes; and along the axial direction of the particulate trap, the carrier wall having a first region, a second region, and a third region, the second region being located between the first region and the third region, the length of the second region being greater than the sum of the lengths of the first region and the third region, the catalyst coating loading of the second region being greater than the catalyst coating loading of the first region, and the catalyst coating loading of the second region being greater than the catalyst coating loading of the third region.

[0008] According to an embodiment of the present invention, the engine exhaust after-treatment device can reduce the back pressure of the particulate collector (≤55mbar) by providing a first region segment, a second region segment, and a third region segment with an axial gradient, which is beneficial to reducing fuel consumption and improving the output torque of the engine. It can also enable the engine exhaust after-treatment device to 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 layer has a noble metal, and the total noble metal loading of the catalyst coating layer 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 diameter 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 after-treatment device further includes: a catalytic unit, which is disposed in the exhaust passage, between the particulate trap and the air intake, and is spaced apart from the particulate trap.

[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 differential pipeline, an outlet pressure differential 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 differential pipeline and the exhaust channel, the third connecting hole connects the outlet pressure differential pipeline and the exhaust channel, the intake pressure differential pipeline and the outlet pressure differential 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 arranged 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 includes the engine exhaust after-treatment device according to the above embodiment.

[0024] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by 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 readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

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

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

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

[0029] Reference numerals:

[0030] Engine exhaust after-treatment device 100;

[0031] Exhaust pipe 1; exhaust channel 11; air intake 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 pipe 4; exhaust gas reflow device 41;

[0039] Intake pressure differential line 5;

[0040] Outlet pressure differential pipeline 6;

[0041] Bellows 7;

[0042] Exhaust line with hump pipe 8. DETAILED DESCRIPTION

[0043] The following describes embodiments of the present invention in detail. Examples of the embodiments 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 intended only to explain the present invention and are not to be construed as limiting the present invention.

[0044] Reference below Figures 1-3 An engine exhaust after-treatment device 100 according to an embodiment of the present invention will be described.

[0045] like Figure 1 and Figure 3 As shown, an engine exhaust after-treatment device 100 according to an 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 is connected to the air inlet 12 and the air outlet; a particulate trap 2, the particulate trap 2 is arranged in the exhaust channel 11, the particulate trap 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 trap 2, and the inlet channel 21 and the outlet channel 22 both extend along the axial direction of the particulate trap 2, the particulate trap 2 has a carrier wall 23, the carrier wall 23 is located between adjacent inlet channels 21 and outlet channels 22, and the carrier wall 23 is formed with a plurality of through holes, 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 catalyst coating 24 loading amount of the second area segment 232 is greater than the catalyst coating 24 loading amount of the first area segment 231, and the catalyst coating 24 loading amount of the second area segment 232 is greater than the catalyst coating 24 loading amount of the third area segment 233.

[0046] During vehicle operation, exhaust gas is generated. This exhaust gas flows into exhaust pipe 1 through its inlet 12 and is then filtered and discharged through its outlet. A particulate filter 2 is disposed within exhaust passage 11 to effectively reduce particulate matter emissions. The inlet channel 21 and outlet channel 22 of the particulate filter 2 are arranged radially along the particulate filter 2 and extend axially along the particulate filter 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. Furthermore, a carrier wall 23 is provided between adjacent inlet channels 21 and outlet channels 22. Along the arrangement direction of the inlet channels 21 and 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 smoothly discharging 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 comprise 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, e.g., cerium-zirconium oxide). By providing a catalyst coating 24 on the surface of the carrier wall 23, particulate matter in the exhaust gas emitted by an 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, applying 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 particulate trap 2, the carrier wall 23 comprises a first section 231, a second section 232, and a third section 233. The sum of the lengths of the first section 231, the second section 232, and the third section 233 is the axial length of the carrier wall 23 along the particulate trap 2. The second section 232 is located between the first section 231 and the third section 233. In other words, the first section 231, the second section 232, and the third section 233 are arranged in sequence along the axial direction of the particulate trap 2. The length of the second section 232 is greater than the sum of the lengths of the first section 231 and the third section 233. The catalyst coating 24 loading (the dry mass of the catalyst coating 24 per unit volume within the region) of the second section 232 is greater than that of the catalyst coating 24 in the first section 231, and the catalyst coating 24 loading of the second section 232 is greater than that of the third section 233.

[0051] It should be noted that the lengths of the first section 231 and the second section 232 are not zero. By configuring the first section 231, the second section 232, and the third section 233 to satisfy the aforementioned relationship, the engine exhaust after-treatment device 100 can meet development requirements, even if the particulate trap 2 simultaneously achieves low back pressure (≤55 mbar) and high filtration efficiency (≥85%) to meet the requirements of next-generation emission regulations.

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

[0053] Example 1: This example illustrates a general method for preparing a particle trap 2 having a gradient of axially varying amounts of catalyst coating 24. The particle trap 2 has dimensions of 118.4 mm (diameter) and 127 mm (height), a 300 mesh carrier wall 23, and a thickness of 0.008 inches.

[0054] A typical slurry preparation process for the catalyst coating 24 is as follows: 52 mass units of γ-alumina and 52 mass units of a cerium-zirconium oxygen storage material (comprising 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 added to an appropriate amount of deionized water to form a suspension. An aqueous solution of platinum group metal active center precursors (palladium nitrate and rhodium nitrate) is added to the suspension, wherein the total amount of precious metal precursors (calculated as palladium and rhodium) is 0.15 mass units, and the palladium:rhodium ratio (by mass) is 1:1. The pH of the suspension is adjusted to 5.5 using glacial acetic acid, and the slurry is ball-milled to obtain a slurry with a particle size distribution of 2.6 microns (D50) and 13 microns (D90). This is the platinum group metal catalyst slurry. The same slurry will be used to prepare the following examples and comparative examples.

[0055] A typical slurry coating procedure for the catalyst coating 24 is as follows: the above-mentioned platinum group metal catalyst slurry is adjusted to a suitable solid content, and then the carrier wall 23 of the particulate collector 2 is taken and placed under a coating fixture. The slurry is evenly coated on the target length of the carrier wall 23 from one end face by vacuum suction and air blowing. The carrier wall 23 coated with the slurry is placed at 180°C for drying for 1 hour, and then calcined at 450°C for 2 hours. If multiple coatings are required, the calcined carrier wall 23 can be cooled to room temperature and then coated with the subsequent catalyst coating 24. Each coating requires the same drying and calcining steps until the target coating pattern 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 loading area can be qualitatively determined by X-ray photography, 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 particulate 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 was performed from the second open end 221, with a coating length of 100% of the total carrier length, i.e. 127 mm, and a coating weight of the finished catalyst coating 24 was 75 g / L. In this embodiment, the first section 231 was 127 mm.

[0061] Example 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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 54% of the total carrier length, i.e., 68.5 mm. The coating weight of the catalyst coating 24 in the first coating was 69.4 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 54% of the total carrier length, i.e., 68.5 mm. The coating weight of the catalyst coating 24 in the second coating was 69.4 g / L.

[0064] In this embodiment, the first and second coatings have an overlapping region, which is the length of the second segment 232. The length of the second 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 segment 232 = 68.5 mm + 68.5 mm - 127 mm = 10 mm. The length of the first segment 231 = the length of the second coating - the length of the second segment 232, that is, the length of the first segment 231 = 68.5 mm - 10 mm = 58.5 mm. The length of the third segment 233 = the length of the first coating - the length of the second segment 232, that is, the length of the third segment 233 = 68.5 mm - 10 mm = 58.5 mm.

[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 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 summarized in Table 1 and the calculation process will not be repeated here.

[0067] Embodiment 5:

[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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 62% of the total carrier length, i.e., 78.7 mm. The catalyst coating amount for the first coating was 60.5 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 62% of the total carrier length, i.e., 78.7 mm. The catalyst coating amount for the second coating was 60.5 g / L.

[0070] Example 6:

[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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 75% of the total carrier length, i.e., 95.2 mm. The catalyst coating amount for the first coating was 50 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 75% of the total carrier length, i.e., 95.2 mm. The catalyst coating amount for the second coating was 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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 88% of the total carrier length, i.e., 111.8 mm. The catalyst coating amount of the first coating was 42.6 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 88% of the total carrier length, i.e., 111.8 mm. The catalyst coating amount of the second coating 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] Following the coating procedure described in Example 1, a first coating was performed from the first open end 211. The coating length was 100% of the total support length, i.e., 127 mm. The catalyst coating amount for the first coating was 37.5 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 100% of the total support length, i.e., 127 mm. The catalyst coating amount for the second coating was 37.5 g / L.

[0079] Embodiment 9:

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

[0082] Embodiment 10:

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

[0085] Example 11:

[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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 100% of the total support length, i.e., 127 mm. The catalyst coating amount for the first coating was 20 g / L. After drying and sintering, a second coating was performed from the second open end 221. The coating length was 33% of the total support length, i.e., 41.9 mm. The catalyst coating amount for the second coating was 83.3 g / L. After drying and sintering, a third coating was performed from the first open end 211. The coating length was 33% of the total support length, i.e., 41.9 mm. The catalyst coating amount for the third coating was 83.3 g / L.

[0088] Example 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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 100% of the total carrier length, i.e., 127 mm. The catalyst coating amount for the first coating was 50 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 50% of the total carrier length, i.e., 63.5 mm. The catalyst coating amount for the second coating was 50 g / L.

[0091] Example 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] Following the coating procedure described in Example 1, a first coating was performed from the second open end 221. The coating length was 50% of the total carrier length, i.e., 63.5 mm. The catalyst coating amount for the first coating was 50 g / L. After drying and sintering, a second coating was performed from the first open end 211. The coating length was 100% of the total carrier length, i.e., 127 mm. The catalyst coating amount for the second coating was 50 g / L.

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

[0095]

[0096] Table 1

[0097] Example 14:

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

[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. Back pressure test equipment is carried out, measured and recorded at 600m 3 / h air flow rate of the particle collector 2 cold flow back pressure.

[0100] The filtration efficiency of Comparative Example 2, Comparative Example 3, Examples 4 to 7, Comparative Examples 8, and Examples 9 to 13 was evaluated on an engine test bench equipped with a 1.5LT-GDI engine of a certain brand as the test engine. The test cycle was the WLTC cycle, and the particulate filter 2 to be tested was installed in a tight coupling position behind the engine using a simple straight-tube package. Each simple package of the particulate filter 2 was tested three times under the WLTC cycle, and the PN value 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 10nm 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] Number Cold flow back pressure / mbar Average filtration efficiency / % Comparative Example Two 47.0 82 Comparative Example Three 54.1 76 Example Four 57.0 74 Example Five 52.3 71 Example Six 50.9 79 Example Seven 53.5 88 Comparative Example Eight 66.2 88 Example Nine 51.2 85 Example Ten 52.4 87 Example Eleven 65.8 80 Example Twelve 65.8 74 Example Thirteen 62.2 72

[0105] Table 2

[0106] The above experimental results demonstrate that the lengths of the three regions and the amount of catalyst coating in each region are two primary parameters influencing the backpressure and filtration efficiency of the particulate trap 2. Particulate traps 2 that simultaneously achieve high filtration efficiency (≥85%) and low backpressure (≤55 mbar), such as those in Examples 7, 9, and 10, have a second region length that is greater than the sum of the lengths of the first region 231 and the third region 233, and a catalyst coating 24 loading in the second region 232 that is greater than the sum of the catalyst coating 24 loading in the first region 231 and the catalyst coating 24 loading in 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 Examples 4 to 7 and 9 to 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 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.

[0110] Specifically, along the axial direction of the particulate trap 2, the particulate trap 2 has a first open end 211 and a second open end 221. It should be noted that, along the exhaust gas flow direction, the first open end 211 is upstream of the carrier wall 23, and the second open end 221 is downstream of the carrier wall 23. The first section 231 is upstream of the third section 233. The first catalyst coating 24 is applied from the second open end 221, and after drying and sintering, the second catalyst coating 24 is applied from the first open end 211. If the sum of the lengths of the first and second coatings is greater than the total length of the carrier wall 23, there is an overlap between the first and second coatings. This overlap is the second section 232. The coating amount of the second section 232 is the sum of the coating amounts of the first and second catalyst coatings. That is, the catalyst coating 24 loading of the second section 232 is greater than or equal to the sum of the catalyst coating 24 loadings of the first and third sections 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 conducive to conducting various 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 loading amount of the catalyst coating 24 in the first section 231, the second section 232 and the third section 233 is D, which satisfies 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 reasonably set, 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 section 231 is D1, the loading amount of the catalyst coating 24 in the second section 232 is D2, and the loading amount of the catalyst coating 24 in the third section 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 passing 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 in 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 in the second area segment 232 satisfies the relationship: 85g / L≤D2<240g / L, the loading amount D2 of the catalyst coating 24 in the second area segment 232 can be 85g / L, 90g / L, 239g / L, the loading amount D3 of the catalyst coating 24 in the third area segment 233 satisfies the relationship: 40g / L≤D3<240g / L, the loading amount D3 of the catalyst coating 24 in the third area segment 233 can be Values ​​such as 40g / L, 60g / L, and 239g / L can make the catalyst coating 24 loading of the first section 231, the catalyst coating 24 loading of the second section 232, and the catalyst coating 24 loading of the third section 233 all set reasonably, which is beneficial to reducing the risk of insufficient exhaust gas filtration caused by too small catalyst coating 24 loading of the first section 231, the catalyst coating 24 loading of the second section 232, and the catalyst coating 24 loading of the third section 233, and can also reduce the risk of increased back pressure or increased production costs caused by too large catalyst coating 24 loading of the first section 231, the catalyst coating 24 loading of the second section 232, and the catalyst coating 24 loading of the third section 233.

[0117] In some embodiments of the present invention, Figure 3 As shown, the length of the first section 231 and the length of the third section 233 are the same.

[0118] Among them, in Examples 4 to 7 and 11 to 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 improving 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. In some embodiments of the present application, the precious metal may be a platinum group metal such as platinum, rhodium, or palladium. 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 can 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] 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%. In other words, the porosity P of the carrier wall 23 is between 45% and 70%. The porosity P of the carrier wall 23 can be 45%, 50%, 60%, 70%, and other values. This setting can reasonably set the porosity of the carrier wall 23, reduce the risk of excessive back pressure caused by too low a porosity of the carrier wall 23, and reduce the risk of insufficient exhaust gas filtration caused by too high a porosity of the carrier wall 23.

[0123] In some embodiments of the present invention, Figure 3 As shown, the 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.

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

[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] In the axial direction of the particulate filter 2, i.e., the direction of exhaust gas flow, the inlet channel 21 has a first open end 211, through which exhaust gas can flow into the inlet channel 21. The outlet channel 22 has a second open end 221, through which exhaust gas can flow out of the outlet channel 22. The first open end 211 and the second open end 221 are respectively located at opposite ends of the particulate filter 2. It should be noted that the first open end 211 is located upstream of the second open end 221. This arrangement aligns the arrangement of the first open end 211 and the second open end 221 with the direction of exhaust gas flow, facilitating exhaust gas flow 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, thereby achieving smooth filtration and exhaust gas discharge.

[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. There are multiple carrier walls 23, and a carrier wall 23 is provided between each adjacent inlet channel 21 and outlet channel 22.

[0128] Among them, there are multiple inlet channels 21 and multiple 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, thereby achieving a smooth filtering and discharge effect of the exhaust gas.

[0129] In some embodiments of the present invention, Figure 1 As shown, the engine exhaust after-treatment 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 is spaced apart from the particulate trap 2 .

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

[0131] The catalytic unit 3 and the particulate filter 2 are spaced apart. In some embodiments of the present application, the catalytic unit 3 and the particulate filter 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 filter 2 are configured as a close-coupled catalyst, and the catalytic unit 3 and the particulate filter 2 are connected. This is conducive to improving the integration of the engine exhaust after-treatment device 100 and also facilitates the smooth processing of exhaust gas in the engine exhaust after-treatment device 100 and its discharge from the engine exhaust after-treatment device 100.

[0132] In some embodiments of the present invention, Figure 1 As shown, the engine exhaust after-treatment device 100 may further include: an exhaust gas recirculation 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 recirculation pipe 4 and the exhaust channel 11 .

[0133] The first connecting hole is located between the catalytic unit 3 and the particulate filter 2. That is, along the gas flow direction, the first connecting hole is located downstream of the catalytic unit 3 and upstream of the particulate filter 2. The exhaust gas recirculation line 4 and the exhaust pipe 1 can be connected by, but not limited to, welding, so that the first connecting hole connects the exhaust gas recirculation line 4 and the exhaust passage 11. The exhaust gas recirculation line 4 can be connected to the exhaust gas recirculation device 41 by a flange, so that when the engine is operating, the engine exhaust after-treatment device 100 can guide a portion of the exhaust gas from the exhaust gas recirculation line 4 through the exhaust gas recirculation device 41 back to the intake system for mixing with fresh air, thereby lowering the temperature of the combustion chamber and effectively reducing NOx emissions. In addition, the exhaust gas recirculation device 41 can reduce fuel consumption, 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 after-treatment 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, 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, 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 provided in the exhaust pipeline 1 and is located between the catalytic unit 3 and the particulate trap 2, and the second temperature sensor (not shown in the figure) is provided 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 facing away from the catalytic unit 3. That is, along the exhaust gas flow direction, the catalytic unit 3, the second connecting hole, the particulate trap 2, and the third connecting hole are arranged in that order. The first temperature sensor is located in the exhaust line 1 between the catalytic unit 3 and the particulate trap 2, and the second temperature sensor is located in the exhaust line 1 on the side of the particulate trap 2 facing away from the catalytic unit 3. That is, along the exhaust gas flow direction, the catalytic unit 3, the first temperature sensor, the particulate trap 2, and the second temperature sensor are arranged in that order.

[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 conducive 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 is formed with an air inlet 12, the third pipe section 16 is formed with 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, an insulation layer 142 and an outer pipe layer 143, the outer pipe layer 143 is sleeved on the inner pipe layer 141, and the 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 exhaust gas flow direction, 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 forms an air inlet 12, through which the exhaust gas flows into the first pipe section 14. The third pipe section 16 forms an air outlet (not shown in the figure), through which the exhaust gas flows out after being filtered within the engine exhaust aftertreatment device 100. The particulate filter 2 is disposed within the second pipe section 15. The first pipe section 14 includes an inner pipe layer 141, an insulating layer 142, and an outer pipe layer 143. The outer pipe layer 143 is sleeved over the inner pipe layer 141, and the insulating layer 142 is disposed between the inner and outer pipe layers 141 and 143.

[0139] The provision of a first pipe section 14 with an insulation layer 142 provides insulation, effectively alleviating the issues of reduced exhaust temperature and low pollutant conversion efficiency caused by frequent engine starts in plug-in hybrid vehicles. Furthermore, the insulation layer 142 quickly raises the exhaust temperature to the ignition temperature of exhaust pollutants, reducing ignition time and improving pollutant conversion efficiency. Furthermore, this structure also provides thermal insulation, reducing the risk of damage to surrounding components of the exhaust caused by excessively high engine exhaust aftertreatment device 100, thereby mitigating the risk of thermal damage to the entire vehicle.

[0140] As some embodiments of this application, Figure 1 As shown, the engine exhaust after-treatment 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. The bellows 7 provides a shock-absorbing effect. The boss structure of the exhaust pipe 81 facilitates the connection of the engine exhaust after-treatment device 100 to subsequent pipelines via clamps, eliminating the need for flange connections. This effectively reduces the weight of the engine exhaust after-treatment device 100 and contributes 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 filter 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 examples 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, such as 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 embodiment.

[0145] The vehicle according to the embodiment of the present application includes the engine exhaust aftertreatment device 100 of the above-mentioned embodiments. By arranging the first region section 231, the second region section 232 and the third region section 233 with axial gradient, the particulate filter 2 can have a lower back pressure (≤55 mbar), which is beneficial to reduce the fuel consumption of the vehicle and increase the output torque of the engine. Also, the engine exhaust aftertreatment device 100 can have a higher filtration efficiency (≥85%) for particulate matters with a particle size ranging from 10 nm to 3 μm, so as to meet the next generation of emission regulation requirements.

[0146] In the description of the specification, the description referring to the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the exemplary description of the above-mentioned terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

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

Claims

1. An engine exhaust after-treatment device, characterized in that: include: an exhaust pipe, the exhaust pipe being formed with an exhaust passage, the exhaust pipe having an air inlet and an air outlet, the exhaust passage communicating with the air inlet and the air outlet; a particulate trap disposed in the exhaust passage, the particulate trap forming an inlet channel and an outlet channel, the inlet channel and the outlet channel being arranged radially of the particulate trap and both extending axially of the particulate trap, the particulate trap having a carrier wall, the carrier wall being located between adjacent inlet channels and outlet channels, the carrier wall being formed with a plurality of through holes, the through holes communicating with the inlet channels and the outlet channels, a catalyst coating being provided on a surface of the carrier wall and / or an inner wall of the through holes; 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 after-treatment 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 after-treatment 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 after-treatment 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 after-treatment 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 after-treatment 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 after-treatment 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 after-treatment 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 after-treatment 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 after-treatment 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. The first open end and the second open end are respectively located at two ends of the particle trap.

11. The engine exhaust after-treatment 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 provided between each adjacent inlet channel and outlet channel.

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

13. The engine exhaust after-treatment device according to claim 12, characterized in that: Also includes: An exhaust gas recirculation pipe is formed in the exhaust pipe and has a first communicating hole, the first communicating hole is located between the catalytic unit and the particulate trap, and the first communicating hole communicates the exhaust gas recirculation pipe and the exhaust passage.

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

15. The engine exhaust after-treatment device according to any one of claims 1 to 11, characterized in that: 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 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 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.

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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