Mixer, aftertreatment system and vehicle

Abstract

The invention discloses a mixer, an aftertreatment system and a vehicle. The mixer comprises a first shell, a second shell and a plurality of partition pieces. The second shell is arranged in the first shell, the first shell and the second shell are arranged in a spaced mode, and the two ends, in the central axis direction of the second shell, of the second shell and the first shell are arranged in an open mode; one ends of the plurality of separators are mutually connected along the direction vertical to the central axis of the second shell, and the other ends of the plurality of separators are respectively connected with the second shell and the first shell along the direction vertical to the central axis of the second shell. Therefore, the coating area of the catalyst coating can be effectively increased, so that the contact area of urea and the catalyst coating is increased, decomposition and utilization of urea are promoted, the conversion rate of urea is increased, the exhaust emission of an engine is reduced, and the purpose of reducing air pollution is achieved. The reliability and the production efficiency of the mixer are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a mixer, a post-processing system and a vehicle. Background Art

[0002] In the prior art, the coating area of ​​the catalyst in the mixer is small, resulting in a small contact area between urea and the catalyst and a low conversion rate of urea. Summary of the invention

[0003] 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 a mixer that can improve the conversion rate of urea.

[0004] A second object of the present invention is to provide a post-treatment system, comprising the mixer in the above embodiment.

[0005] A third object of the present invention is to provide a vehicle, comprising the mixer or the after-treatment system in the above embodiment.

[0006] According to a mixer of an embodiment of the first aspect of the present invention, the mixer includes: a first shell, a second shell and a plurality of partitions, the second shell is arranged in the first shell, the first shell and the second shell are spaced apart, and the second shell and the first shell are open at both ends along the central axis direction of the second shell respectively; the plurality of partitions are spaced apart along the circumference of the second shell, one ends of the plurality of partitions are connected to each other along a direction perpendicular to the central axis of the second shell, and the other ends of the plurality of partitions are respectively connected to the second shell and the first shell along a direction perpendicular to the central axis of the second shell.

[0007] According to the mixer of the embodiment of the present invention, the straight-through design of the mixer optimizes the internal structure of the mixer, and multiple partitions are arranged in the mixer at intervals along the circumference of the second shell, which can effectively increase the coating area of ​​the catalyst coating, thereby increasing the contact area between urea and the catalyst coating, thereby promoting the decomposition and utilization of urea, improving the conversion rate of urea, reducing the emission of engine exhaust gas, and achieving the purpose of reducing air pollution. At the same time, since the structure of the mixer is relatively simple, the processing difficulty of the mixer can be reduced, and the reliability and production efficiency of the mixer can be improved.

[0008] In some embodiments, the cross-sectional shapes of the first shell and the second shell are circular.

[0009] In some embodiments, the one ends of the plurality of partitions are connected to each other at a central axis position of the second shell.

[0010] In some embodiments, the number of the separators is N, and N satisfies: 2≤N≤16.

[0011] In some embodiments, the first shell is a metal piece; and / or, the second shell is a metal piece; and / or, the partition is a metal piece.

[0012] In some embodiments, the partition is connected to the first shell and the second shell by welding; and / or, a plurality of the partitions are connected by welding.

[0013] In some embodiments, a portion of the partition defines a plurality of first flow channels with the first shell and the second shell, and a portion of the partition defines a plurality of second flow channels with the second shell. The plurality of first flow channels are spaced apart along the circumference of the second shell, and the plurality of second flow channels are spaced apart along the circumference of the second shell, and a cross-sectional area of ​​the first flow channel is greater than a cross-sectional area of ​​the second flow channel.

[0014] In some embodiments, the mixer further includes: a catalyst coating, wherein the catalyst coating is disposed on a surface of an area enclosed by the first shell, the second shell, and the partition.

[0015] In some embodiments, the catalyst coating includes a nanoporous oxide and a molecular sieve, and the nanoporous oxide and / or the molecular sieve are formed with a plurality of pore structures.

[0016] In some embodiments, the nanoporous oxide includes titanium dioxide and zirconium dioxide.

[0017] The post-treatment system according to the second aspect of the present invention comprises the mixer described in any one of the above embodiments.

[0018] In some embodiments, the aftertreatment system further includes: a catalyst and a nozzle device, and the mixer is disposed between the nozzle device and the catalyst.

[0019] The vehicle according to the third aspect of the present invention comprises the mixer or the post-treatment system according to any one of the above embodiments.

[0020] 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

[0021] 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: Figure 1 is a schematic diagram from one perspective of a mixer provided with four partitions according to an embodiment of the present invention; Figure 2 is a schematic diagram from another perspective of a mixer provided with four partitions according to an embodiment of the present invention; Figure 3 is a schematic diagram of a mixer provided with eight partitions from one viewing angle according to an embodiment of the present invention; Figure 4 2 is a schematic diagram from another perspective showing that eight partitions are provided in a mixer according to an embodiment of the present invention.

[0022] Reference numerals: 100. Mixer; 10. First shell; 11. Second shell; 12. Partition; 13. First flow channel; 14. Second flow channel. DETAILED DESCRIPTION

[0023] The embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Figure 1-Figure 4 The mixer 100 according to the embodiment of the present invention is described. The mixer 100 includes a first housing 10 , a second housing 11 , and a plurality of partitions 12 .

[0024] Specifically, if Figure 1-Figure 4 As shown, the second shell 11 is arranged in the first shell 10, the first shell 10 and the second shell 11 are arranged at intervals, and the second shell 11 and the first shell 10 are respectively opened at both ends along the central axis direction of the second shell 11; a plurality of partitions 12 are arranged at intervals along the circumference of the second shell 11, one ends of the plurality of partitions 12 are connected to each other along a direction perpendicular to the central axis of the second shell 11, and the other ends of the plurality of partitions 12 are respectively connected to the second shell 11 and the first shell 10 along a direction perpendicular to the central axis of the second shell 11.

[0025] The first shell 10 and the second shell 11 are hollow tubular structures. The first shell 10 extends along the central axis of the second shell 11. The second shell 11 is arranged inside the first shell 10 at intervals. The central axis of the first shell 10 coincides with the central axis of the second shell 11, that is, the first shell 10 is sleeved on the outside of the second shell 11. Both ends of the first shell 10 and the second shell 11 along the central axis of the second shell 11 are connected to the engine exhaust pipeline so that the engine exhaust gas and the urea aqueous solution enter the mixer 100. A plurality of partitions 12 extend along the central axis of the second shell 11. Parts of the plurality of partitions 12 are arranged inside the second shell 11, and parts of the plurality of partitions 12 are arranged between the first shell 10 and the second shell 11. One end of the plurality of separators 12 away from the first shell 10 is connected to the central axis of the second shell 11, and the other ends of the plurality of separators 12 extend radially from the inside to the outside along the radial direction of the second shell 11 in a direction away from the central axis of the second shell 11 and in a direction toward the first shell 10, and are arranged at intervals along the circumference of the second shell 11 on the inner surface of the first shell 10, that is, the side surface of the first shell 10 facing the second shell 11. In this embodiment, the plurality of separators 12 are centrally symmetrical about the central axis of the second shell 11, and the surfaces of the separators 12, the side surface of the first shell 10 facing the second shell 11, and the two side surfaces of the second shell 11 along the radial direction are respectively suitable for coating a catalyst coating that promotes the decomposition of urea.

[0026] According to the mixer 100 of the embodiment of the present invention, the internal structure of the mixer 100 is optimized through the straight-through design of the mixer 100, and the plurality of partitions 12 are arranged in the mixer 100 at intervals along the circumference of the second shell 11, which can effectively increase the coating area of ​​the catalyst coating, thereby increasing the contact area between urea and the catalyst coating, thereby promoting the decomposition and utilization of urea, improving the conversion rate of urea, reducing the emission of engine exhaust gas, and achieving the purpose of reducing air pollution. At the same time, since the structure of the mixer 100 is relatively simple, the processing difficulty of the mixer 100 can be reduced, and the reliability and production efficiency of the mixer 100 can be improved.

[0027] According to some embodiments of the present invention, Figure 2 and Figure 4 As shown, the cross-sectional shape of the first shell 10 and the second shell 11 is circular.

[0028] That is, the cross-sectional shapes of the first shell 10 and the second shell 11 are concentric circles. Therefore, by designing the cross-sectional shapes of the first shell 10 and the second shell 11 to be circular, the area on which the catalyst coating can be coated on the mixer 100 is increased, which can facilitate the full contact between the catalyst coating and urea inside the mixer 100, improve the conversion rate of urea, reduce the resistance pressure of the exhaust gas in the mixer 100, that is, reduce the exhaust back pressure, ensure that the engine exhaust gas passes through the mixer 100 smoothly, avoid affecting the performance of the engine, and at the same time, facilitate the processing of the mixer 100 and improve the structural strength of the mixer 100.

[0029] According to some embodiments of the present invention, Figure 1-Figure 4 As shown, the ends of the plurality of partitions 12 away from the first shell 10 are connected to each other at the central axis position of the second shell 11 .

[0030] The ends of the plurality of separators 12 that are radially away from the first shell 10 of the second shell 11 are connected together at the central axis of the second shell 11. Thus, the structural strength of the plurality of separators 12 can be improved, the spatial structure inside the mixer 100 can be optimized, the stability and reliability of the separator 12 arrangement can be increased, the space occupied by the separator 12 inside the mixer 100 can be reduced, and the coating area of ​​the catalyst coating on the separator 12 can be increased. At the same time, the intake amount of the engine exhaust gas entering the mixer 100 can be increased, thereby minimizing the emission of the engine exhaust gas.

[0031] According to some embodiments of the present invention, the number of the separators 12 is N, and N satisfies: 2≤N≤16.

[0032] When the number of separators 12 is less than 2, the number of separators 12 is too small. Although the porosity in the mixer 100 is large and the exhaust back pressure is small, the coating area of ​​the catalyst coating in the mixer 100 is reduced, the contact area between the catalyst coating and urea is reduced, and the conversion rate of urea is reduced; when the number of separators 12 is greater than 16, the number of separators 12 is too large. Although the contact area between the catalyst coating and urea is increased, the porosity in the mixer 100 is small and the exhaust back pressure is large, which is easy to affect the fuel economy of the vehicle and increase the cost. For example, N=4 or N=8.

[0033] Therefore, by limiting the number range of the separators 12, the coating area of ​​the catalyst coating in the mixer 100 can be increased, the contact area between the catalyst coating and urea can be increased, the conversion rate of urea can be improved, and the emission of engine exhaust gas can be reduced. At the same time, the porosity in the mixer 100 can be reduced, the exhaust back pressure can be reduced, and the engine exhaust gas can be ensured to pass through the mixer 100 smoothly, thereby improving the fuel economy of the vehicle.

[0034] Optionally, the number of partitions 12 can be adjusted according to different exhaust flow rates of the engine.

[0035] According to some embodiments of the present invention, the first housing 10 is a metal part. The metal part has excellent thermal conductivity. Therefore, under the condition of low exhaust temperature, it can ensure that the first housing 10 heats up quickly after the engine is started, avoid the urea aqueous solution from contacting the low-temperature first housing 10, avoid the formation of incompletely decomposed crystals on the first housing 10, improve the conversion rate of urea, avoid the blockage of the engine exhaust pipe, avoid the increase of exhaust back pressure, ensure that the engine exhaust gas passes smoothly through the mixer 100, improve the fuel economy of the vehicle, and improve the performance of the engine.

[0036] Optionally, the second housing 11 is a metal part. Thus, it can be ensured that the second housing 11 heats up quickly after the engine is started, so that the urea aqueous solution is prevented from contacting the low-temperature second housing 11, and the formation of incompletely decomposed crystals on the second housing 11 is prevented, thereby improving the conversion rate of urea, preventing the engine exhaust pipe from being blocked, and preventing the exhaust back pressure from increasing.

[0037] Optionally, the separator 12 is a metal part. Thus, it can be ensured that the separator 12 heats up quickly after the engine is started, so that the urea aqueous solution is prevented from contacting the low-temperature separator 12, and the formation of incompletely decomposed crystals on the separator 12 is prevented, so that the conversion rate of urea is improved, the blockage of the engine exhaust pipe is avoided, and the increase of exhaust back pressure is avoided.

[0038] Optionally, the first housing 10, the second housing 11 and the partition 12 are all metal parts. Thus, the urea conversion rate can be further improved and the emission of engine exhaust gas can be further reduced.

[0039] Therefore, the mixer 100 is made of metal material, and the good thermal conductivity of the metal can be used to provide a reaction temperature for the reaction between the urea aqueous solution and the catalyst coating, thereby accelerating the reaction efficiency, avoiding low exhaust temperature, and preventing the urea aqueous solution from being unable to completely decompose and produce complexes due to contact with the low-temperature side wall and poor atomization, and preventing the complexes from accumulating to form crystals and thus clogging the exhaust pipe.

[0040] According to some embodiments of the present invention, the separator 12 is welded to the first shell 10 and the second shell 11. Thus, the separator 12 is manufactured separately from the first shell 10 and the second shell 11, which can reduce the difficulty of processing and improve the connection strength between the separator 12 and the first shell 10 and the second shell 11, thereby improving the reliability of the mixer 100 and extending the service life of the mixer 100.

[0041] Optionally, multiple separators 12 are welded to each other. Thus, multiple separators 12 are manufactured separately, which can reduce the processing difficulty of the separators 12, and at the same time, improve the structural strength and connection strength of the multiple separators 12, prevent the separators 12 from falling off, extend the service life of the separators 12, and improve the reliability and stability of the installation of the separators 12.

[0042] Optionally, the separator 12 is welded to the first shell 10 and the second shell 11, and a plurality of separators 12 are welded to each other. Thus, the connection strength between the separator 12, the first shell 10 and the second shell 11 can be further improved, and the stability and reliability of the mixer 100 can be further improved.

[0043] According to some embodiments of the present invention, Figure 2 and Figure 4 As shown, part of the partition 12 and the first shell 10 and the second shell 11 define a plurality of first flow channels 13, and part of the partition 12 and the second shell 11 define a plurality of second flow channels 14. The plurality of first flow channels 13 are arranged at intervals along the circumference of the second shell 11, and the plurality of second flow channels 14 are arranged at intervals along the circumference of the second shell 11. The cross-sectional area of ​​the first flow channel 13 is greater than the cross-sectional area of ​​the second flow channel 14.

[0044] The side surfaces of two adjacent separators 12 adjacent to each other, the inner surface of the first shell 10 between the two adjacent separators 12, and the outer surface of the second shell 11 define together a first flow channel 13, there are multiple first flow channels 13, the multiple first flow channels 13 are arranged at intervals along the circumference of the second shell 11, and the first flow channel 13 is arranged between the first shell 10 and the second shell 11 along the radial direction of the second shell 11; the side surfaces of two adjacent separators 12 adjacent to each other and the inner surface of the second shell 11 between the two adjacent separators 12 define together a second flow channel 14, there are multiple second flow channels 14, the multiple second flow channels 14 are arranged at intervals along the circumference of the second shell 11. In the present application, the number of the first flow channel 13 and the second flow channel 14 are the same, and the first flow channel 13 and the second flow channel 14 between the two adjacent separators 12 are arranged at intervals along the radial direction of the second shell 11.

[0045] Therefore, by setting the partition 12 and defining a plurality of first flow channels 13 and second flow channels 14, interference between different flow channels can be avoided, and the catalyst coating can be coated in the first flow channels 13 and the second flow channels 14, so that the catalyst coating is evenly distributed in the mixer 100, which facilitates full contact between the catalyst coating and urea, thereby improving the conversion rate of urea.

[0046] According to some embodiments of the present invention, the mixer 100 further includes: a catalyst coating, which is disposed on the surface of the area surrounded by the first shell 10 , the second shell 11 , and the separator 12 .

[0047] In this embodiment, urea is subjected to evaporation, pyrolysis, hydrolysis and other processes to form a reducing agent (NH 3 ammonia) and HNCO (isocyanate), NH 3 NOx x Oxidation-reduction reaction occurs, ultimately reducing NO x For emission purposes, the catalyst coating can catalyze the decomposition of urea and improve the decomposition efficiency of urea.

[0048] The catalyst coating is suitable for promoting the decomposition and utilization of urea, and is respectively coated on the inner surface of the first shell 10 , the inner surface and the outer surface of the second shell 11 , and the two side surfaces of the plurality of separators 12 along the circumferential direction of the second shell 11 .

[0049] Thus, by providing a catalyst coating on the surface of the area surrounded by the first shell 10, the second shell 11 and the separator 12, it is possible to facilitate full contact between urea and the catalyst coating, thereby improving the ability of the catalyst coating to catalyze the decomposition of urea into NH 3 efficiency, improve the conversion rate of urea and reduce the emission of engine exhaust gas.

[0050] Optionally, the catalyst coating loading is 50-150 g / L.

[0051] According to some embodiments of the present invention, the catalyst coating includes a nanoporous oxide and a molecular sieve, the nanoporous oxide is formed with a plurality of pore structures, or the molecular sieve is formed with a plurality of pore structures.

[0052] In this embodiment, both the nanoporous oxide and the molecular sieve have multiple pore structures. This is beneficial to increase the specific surface area of ​​the catalyst coating, increase the contact area between urea and the catalyst coating, improve the decomposition efficiency of urea, and increase the output of NH 3 efficiency and reduce engine exhaust emissions.

[0053] Preferably, the molecular sieve is H-SSZ-13, which can promote the hydrolysis of isocyanic acid, which can generate NH 3 , thereby increasing the overall output of NH 3 efficiency and reduce engine exhaust emissions.

[0054] According to some embodiments of the invention, the nanoporous oxide includes titanium dioxide and zirconium dioxide.

[0055] That is, the nanoporous oxide is nanoporous titanium dioxide (TiO 2 ) and zirconium dioxide (ZrO 2) mixture, titanium dioxide has a higher catalytic activity for the thermal decomposition of urea, and zirconium dioxide has a higher catalytic ability for the hydrolysis of isocyanic acid. This can improve the decomposition efficiency of urea and increase the output of NH 3 efficiency and reduce engine exhaust emissions.

[0056] The post-processing system according to the second embodiment of the present invention comprises the mixer 100 of any one of the above embodiments.

[0057] In this embodiment, by adopting a mixer 100 provided with a plurality of partitions 12, the internal structure of the mixer 100 is optimized, and the catalyst coating is coated on the surface of the area enclosed by the first shell 10, the second shell 11 and the partition 12, thereby increasing the specific surface area of ​​the catalyst coating, providing more catalyst active sites, improving the conversion rate of urea, and reducing the emission of engine exhaust gas. Through the straight-through design of the mixer 100, the exhaust resistance and back pressure can be reduced, so that the engine exhaust gas can pass smoothly without affecting the engine performance. At the same time, the risk of clogging the exhaust pipe after urea crystallization is reduced.

[0058] According to some embodiments of the present invention, the aftertreatment system further includes: a catalyst and a nozzle device, and the mixer 100 is disposed between the nozzle device and the catalyst.

[0059] That is, the mixer 100 is disposed at the front end of the catalyst and at the rear end of the nozzle device, wherein the catalyst is a selective catalytic reduction (SCR) catalyst and the nozzle device is a urea nozzle device.

[0060] Thus, by arranging the mixer 100 between the nozzle device and the catalyst, the isocyanic acid hydrolysis and NH 3 -SCR reaction competes with the active sites of the copper-based molecular sieve catalyst, making the NH 3 Fully compatible with engine exhaust NO x reaction, reducing engine exhaust emissions and improving the reliability of the after-treatment system.

[0061] The vehicle according to the third aspect of the present invention comprises the mixer 100 or the post-treatment system according to any one of the above embodiments, thereby reducing the emission of exhaust gas from the engine of the vehicle.

[0062] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0063] In the description of the present invention, "first feature" and "second feature" may include one or more of the features. In the description of the present invention, "plurality" means two or more. In the description of the present invention, a first feature "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. In the description of the present invention, a first feature "above", "above" and "above" a second feature may include the first feature being directly above and obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature.

[0064] 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.

[0065] 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. A mixer (100), characterized in that: include: A first housing (10); a second shell (11), the second shell (11) being arranged inside the first shell (10), the first shell (10) and the second shell (11) being arranged at a distance from each other, and the second shell (11) and the first shell (10) being open at both ends along the central axis direction of the second shell (11); A plurality of partitions (12), wherein the plurality of partitions (12) are arranged at intervals along the circumference of the second shell (11), one ends of the plurality of partitions (12) are connected to each other along a direction perpendicular to the central axis of the second shell (11), and the other ends of the plurality of partitions (12) are respectively connected to the second shell (11) and the first shell (10) along a direction perpendicular to the central axis of the second shell (11).

2. The mixer (100) according to claim 1, characterized in that The cross-sectional shapes of the first shell (10) and the second shell (11) are circular.

3. The mixer (100) according to claim 1, characterized in that The one ends of the plurality of partitions (12) are connected to each other at a central axis position of the second shell (11).

4. The mixer (100) according to claim 1, characterized in that The number of the separators (12) is N, and N satisfies: 2≤N≤16.

5. The mixer (100) according to claim 1, characterized in that The first shell (10) is a metal part; and / or, The second shell (11) is a metal part; and / or, The separator (12) is a metal piece.

6. The mixer (100) according to claim 1, characterized in that The partition (12) is welded to the first shell (10) and the second shell (11); and / or, The plurality of separators (12) are connected by welding.

7. The mixer (100) according to claim 1, characterized in that Part of the partition (12) and the first shell (10) and the second shell (11) define a plurality of first flow channels (13), and part of the partition (12) and the second shell (11) define a plurality of second flow channels (14), the plurality of first flow channels (13) being arranged at intervals along the circumference of the second shell (11), and the plurality of second flow channels (14) being arranged at intervals along the circumference of the second shell (11), The cross-sectional area of ​​the first flow channel (13) is greater than the cross-sectional area of ​​the second flow channel (14).

8. The mixer (100) according to any one of claims 1 to 7, characterized in that: Also includes: A catalyst coating, wherein the catalyst coating is provided on a surface of an area enclosed by the first shell (10), the second shell (11) and the separator (12).

9. The mixer (100) according to claim 8, characterized in that The catalyst coating layer includes a nanoporous oxide and a molecular sieve, wherein the nanoporous oxide and / or the molecular sieve are formed with a plurality of pore structures.

10. The mixer (100) according to claim 9, characterized in that The nanoporous oxide includes titanium dioxide and zirconium dioxide.

11. A post-processing system, characterized in that: Comprising a mixer (100) according to any one of claims 1-10.

12. The post-treatment system according to claim 11, characterized in that: Also includes: Catalyst; A nozzle device, wherein the mixer (100) is arranged between the nozzle device and the catalyst.

13. A vehicle, characterized in that: The invention comprises a mixer (100) according to any one of claims 1 to 10, or a post-treatment system according to any one of claims 11 to 12.

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