Adjustable end cover integrated mixer and corresponding aftertreatment system
By designing an adjustable end cap integrated mixer and using valve components to control exhaust gas flow and bypass channels, the problems of unsatisfactory mixing effect and urea crystallization in the mixer were solved, achieving efficient exhaust gas treatment and low back pressure, thus improving the emission performance of diesel vehicles.
Patent Information
- Application Number
- CN202520001394.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2025-11-07
- Estimated Expiration
- 2035-01-02
AI Technical Summary
In existing diesel vehicle exhaust aftertreatment systems, the mixing effect of the mixer is not ideal, the back pressure is high, and urea crystals are easily generated, resulting in poor engine fuel economy and low NOx conversion efficiency, which poses even greater challenges after the upgrade to China VII regulations.
An adjustable end-cap integrated mixer is designed. By setting a mixing pipe and baffle inside the end-cap housing, and using a valve assembly to control the flow of tail gas under different pressures, a bypass channel is realized. It has high integration, good mixing effect, excellent anti-crystallization performance, and can regulate the distribution of airflow and ammonia, thereby improving the reduction reaction capacity.
This design achieves a compact mixer with low back pressure, good mixing effect, prevents urea crystallization, improves the reduction efficiency of nitrogen oxides, and enhances the engine's fuel economy and NOx conversion efficiency.
Smart Images
Figure CN223523813U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to tail gas treatment technical field especially, it is a kind of adjustable end cap integrated mixer and corresponding post-processing system. BACKGROUND
[0002] With the continuous upgrading of domestic diesel vehicle emission regulations, more stringent requirements are put forward for automobile exhaust aftertreatment system and its core component mixer. As a key component in the aftertreatment system, the performance of the mixer directly affects the emission of NOx.
[0003] The mixer needs to ensure that the exhaust gas and the reducing agent (such as urea solution) are fully mixed to improve the conversion efficiency of the SCR system. The mixer also needs to have good heat exchange performance to ensure that the urea solution is rapidly vaporized and fully mixed with the exhaust gas during the injection process, which helps to improve the conversion efficiency of the SCR system and reduce urea consumption. Due to the more stringent emission limits of "China VI" standard under low temperature and low load conditions, and the increase of injection amount, the risk of crystallization of the mixer increases. The generation of a large amount of crystallization will block the aftertreatment channel, causing the back pressure of the aftertreatment system to rise, the vehicle power to be insufficient, and the risk of emission exceeding the regulatory limits.
[0004] With the upgrading of diesel engine national seven regulations, urea double injection system is one of the important solutions. Compared with the national six exhaust aftertreatment system, urea injection needs to be added at the inlet of the aftertreatment system, and the front mixer and SCR catalyst need to be added, which poses a great challenge to the boundary of the aftertreatment system. The general technical solution adopts a simple mixer in the front exhaust pipe, which has many shortcomings: the mixing effect is not ideal, the back pressure is high, and urea crystallization is easy, etc.
[0005] In general, with the upgrading of regulations, there are still problems: the space arrangement challenge of the front mixer and the aftertreatment system is high under national seven; the back pressure of the mixer and the aftertreatment system is high, which leads to poor engine fuel economy; the urea crystallization in the mixer and the low mixing efficiency of urea and exhaust gas, low De-NOx conversion efficiency, etc. SUMMARY
[0006] In view of the deficiencies of the existing technology, the utility model provides a kind of adjustable end cap integrated mixer and corresponding post-processing system.
[0007] To achieve the above object, the utility model discloses a first aspect provides an adjustable end cover integrated mixer has the following technical scheme: including end cover shell, the end cover shell has the open end, the closed end opposite with the open end and the lateral wall between the open end and the closed end, the open end is used to connect the front processor, first aperture and second aperture are independently arranged respectively on the lateral wall of the end cover shell, the first aperture is used to install the nozzle, the second aperture is the air inlet of the mixer, the inner chamber of the end cover shell sets up the mixing pipe and the baffle, the mixing pipe passes through the baffle and sets up in the inner chamber of the end cover shell, the inner chamber of the end cover shell is separated into the first cavity and the second cavity by the baffle, all tail gas enters the first cavity through the air inlet of the mixer, the mixing pipe has the inlet for air and the outlet for air, the inlet of the mixing pipe is located in the first cavity, the outlet of the mixing pipe is located in the second cavity, the part of the open end of the end cover shell corresponding the first cavity is closed, and the part of the open end of the end cover shell corresponding the second cavity is the air outlet of the mixer.
[0008] The baffle sets up at least one valve assembly, and the at least one valve assembly is set to be in a closed state when the exhaust pressure is less than the preset pressure, and in an open state when the exhaust pressure exceeds the preset pressure to form a bypass channel between the first cavity and the second cavity.
[0009] Preferably, an air outlet baffle is arranged between the air outlet and the lower segment of the mixing pipe, the air outlet baffle closes a part of the air outlet, the air outlet baffle is provided with a plurality of third apertures, so that the mixed gas is discharged through the area of the air outlet not closed by the air outlet baffle and the third apertures of the air outlet baffle.
[0010] Preferably, the air outlet baffle is a semicircular plate structure, which matches the profile of the lower half of the air outlet to close the bottom of the air outlet.
[0011] Preferably, the partition plate is provided with a mounting hole, the valve assembly comprises a valve cover plate, a valve seat provided with a through hole, and an elastic member, the through hole of the valve seat is aligned with the mounting hole for installation, the valve cover plate is connected with the valve seat in an openable and closable manner through the elastic member, the opening and closing degree of the valve cover plate under different exhaust pressures is controlled by the elastic force of the elastic member, and the opening and closing of the valve assembly is controlled by the opening and closing of the valve cover plate.
[0012] Preferably, the elastic member is a torsion spring, the torsion spring is arranged on a shaft rod, the shaft rod is installed on the valve seat, one end of the torsion spring abuts against the valve cover plate, and the other end of the torsion spring abuts against the valve seat.
[0013] Preferably, the longitudinal axis of the mixing pipe and the longitudinal axis of the end cover shell form a preset angle, the preset angle is 60°-120°, and the central axes of the first opening and the second opening are perpendicular to the longitudinal axis of the end cover shell.
[0014] Preferably, the part of the open end corresponding to the first cavity is closed by the partition plate, the partition plate has a plate body, the plate body is provided with a mounting hole, the mounting hole is used for allowing the mixing pipe to pass through, and the partition plate has an extension part extending from the plate body towards the first cavity, and the part of the open end corresponding to the first cavity is closed by the extension part.
[0015] Preferably, the mixing pipe comprises a cyclone pipe internally provided with cyclone blades, the upper portion of the cyclone pipe is provided with a plurality of blade windows, the plurality of blade windows form an inlet of the mixing pipe, and gas enters the mixing pipe through the blade windows in a rotating mode; and the nozzle is installed in the first opening through a nozzle mounting seat.
[0016] The second aspect of the utility model provides a kind of post-processing system, it is characterized in that, comprising preprocessor, and the mixer, the mixer is installed as end cap on the preprocessor, and the preprocessor is front SCR or front ASC.
[0017] Preferably, the post-processing system comprises a DOC, a DPF, a post-mixer and a post-processor, the preprocessor is connected in sequence with the inlet of the DOC, the DPF and the post-mixer, the outlet of the post-mixer is connected with the post-processor, the post-processor is a post-SCR or a post-ASC, and the central axis of the air inlet of the adjustable end cap integrated mixer is perpendicular to the central axes of the inlet and outlet of the post-mixer.
[0018] The adjustable end cover integrated mixer and the corresponding post-processing system of the utility model, utilize the end taper of the existing post-processing system entrance, integrated design mixer, high integration, compact space, low back pressure, good mixing effect, good crystallization performance, and, under the preset pressure, the valve assembly opens directly bypasses part of high temperature gas, achieves the effect of controlling the overall back pressure;Under the preset high load, the valve assembly opens, and the high temperature exhaust gas is wrapped outside the mixing pipe to heat the mixing pipe, which can effectively reduce and eliminate crystallization;The opening and closing of the valve assembly can effectively reduce crystallization and generate more ammonia gas for reduction reaction with nitrogen oxides;Through the opening degree control of the valve assembly, the gas flow and ammonia gas distribution of the gas outlet can be adjusted, which can effectively improve the uniformity index of the gas and ammonia gas before SCR, and further improve the reduction reaction capacity with nitrogen oxides. BRIEF DESCRIPTION OF DRAWINGS
[0019] In order to more clearly illustrate the technical scheme in the embodiments of the utility model, the drawings needed in the embodiments are briefly introduced as follows.
[0020] Figure 1 It is a structural schematic diagram of the post-processing system of the utility model.
[0021] Figure 2 It is a principle simplified diagram of the post-processing system of the utility model.
[0022] Figure 3 It is an explosion schematic diagram of the adjustable end cover integrated mixer of the utility model.
[0023] Figure 4 It is a working principle description schematic diagram of the adjustable end cover integrated mixer of the utility model.
[0024] Figure 5 It is a structural schematic diagram of the valve assembly in the adjustable end cover integrated mixer of the utility model. DETAILED DESCRIPTION
[0025] In order to more clearly describe the technical content of the utility model, the following further describes in combination with specific embodiments.
[0026] As Figures 1 to 2 As shown in the principle schematic diagram of the post-processing system of the utility model, wherein the post-processing system includes a preprocessor 4 and an adjustable end cover integrated mixer 1, the adjustable end cover integrated mixer 1 is installed on the preprocessor 4 as an end cover, and the preprocessor 4 is a front SCR or a front ASC.
[0027] As Figures 1 to 2As shown, the post-processing system further comprises a DOC 8, a DPF 5, a post-mixer 3, and a post-processor 9. The pre-processor 4 is connected to the inlet of the DOC 8, the DPF 5, and the post-mixer 3 in sequence. The outlet of the post-mixer 3 is connected to the post-processor 9. The post-processor 9 is a post-SCR or a post-ASC. The central axis of the air inlet of the adjustable end cap integrated mixer is perpendicular to the central axes of the inlet and outlet of the post-mixer. The DOC 8, the DPF 5, the post-mixer 3, the pre-processor 4, and the post-processor 9 can be connected and fixed by flanges, clamps 6, or welding. The DOC (Diesel Oxidation Catalyst) is a diesel oxidation catalyst. The DPF (Diesel Particulate Filter) is a diesel particulate filter. The SCR (Selective Catalytic Reduction) is a selective catalytic reduction device. The ASC (Ammonia Slip Catalyst) is an ammonia oxidation catalyst. The DOC, the DPF, the SCR, and the ASC all contain catalyst carriers.
[0028] In the present embodiment, two clamps 6 are used. One clamp 4 is used to fix and connect the post-mixer 3 and the DPF 5. The other clamp is used to fix and connect the post-mixer 3 and the post-processor 9, so as to achieve the functions of connection and sealing.
[0029] As shown in FIG. 1, Figure 2 As shown in FIG. 1,
[0030] As shown in FIG. 1, Figures 2 to 5As shown, the adjustable end cover integrated mixer is a specific embodiment of the utility model. The adjustable end cover integrated mixer comprises an end cover shell 10, the end cover shell 10 has an open end 19, a closed end opposite to the open end 19 and a side wall between the open end 19 and the closed end, the open end 19 is used to connect a preprocessor, a first opening 20 and a second opening 21 are independently arranged on the side wall of the end cover shell 10, the first opening 20 is used to install a nozzle 2, the second opening 21 is an air inlet of the mixer, engine exhaust enters the adjustable end cover integrated mixer through the air inlet to mix with a reducing agent, a mixing pipe 13 and a partition plate 15 are arranged in the inner cavity of the end cover shell 10, the mixing pipe 13 is arranged in the inner cavity of the end cover shell 10 through the partition plate 15, as shown Figure 3 The inner cavity of the end cover shell 10 is divided into a first cavity 18 and a second cavity through the partition plate 15, the mixing pipe 13 has an inlet for air and an outlet for air, the inlet of the mixing pipe 13 is located in the first cavity 18, the outlet of the mixing pipe 13 is located in the second cavity, the part of the open end 19 of the end cover shell 10 corresponding to the first cavity is closed, and the part of the open end 19 of the end cover shell 10 corresponding to the second cavity is an air outlet of the mixer.
[0031] The partition plate 15 is provided with a pair of valve assemblies 16, and the pair of valve assemblies 16 are symmetrically arranged on both sides of the mixing pipe 13. The pair of valve assemblies 16 are arranged to be in a closed state when the exhaust is less than a preset pressure, and in an open state when the exhaust exceeds the preset pressure to form a bypass channel between the first cavity 18 and the second cavity. When the valve assembly is in the closed state, all the exhaust entering the first cavity 18 enters the mixing pipe 13 through the inlet of the mixing pipe 13, mixes with the reducing agent in the mixing pipe 13, and is discharged through the outlet of the mixing pipe 13 and the air outlet of the mixer and enters the preprocessor. When the valve assembly is in the open state, part of the exhaust entering the first cavity 18 enters the mixing pipe 13 through the inlet; another part of the exhaust entering the first cavity enters the second cavity through the bypass channel formed after the valve assembly is opened and is discharged through the air outlet.
[0032] The adjustable end cover integrated mixer embodiment of the utility model, on the one hand, integrates the end cover and the mixer parts after packaging and processing, and creatively integrates the air inlet and the nozzle of the mixer on the side wall of the end cover shell, the tail gas is mixed with the reducing agent in the mixing pipe after entering the inner cavity, and the open end of the end cover shell can be directly connected with the SCR, the utility model creatively integrates the mixer structure with high integration and compact space, and simultaneously has low back pressure and good mixing effect; on the other hand, the valve assembly is located outside the mixing pipe, can directly bypass the high-temperature exhaust gas, that is, most of the high-temperature exhaust gas is still mixed with the reducing agent in the inside of the mixing pipe, and a small part of the high-temperature exhaust gas is not mixed in the mixing pipe and directly bypasses to the air outlet of the mixer. The bypass control of the valve assembly can adjust the back pressure of the mixer system; the bypass high-temperature gas can directly heat the outer wall of the mixing pipe, reduces and eliminates the risk of urea crystallization; the bypass high-temperature gas can directly heat the outer wall of the mixing pipe, improves the urea evaporation rate, and further improves the nitrogen and oxygen removal efficiency; the opening control of the valve assembly can adjust the airflow and ammonia gas uniformity index on the surface of the SCR.
[0033] The number of valve assemblies 16 can also be one or more, and the valve diameter of the valve assemblies 16 can also be varied, and the utility model is not limited in this regard.
[0034] As shown in Figure 3 and Figure 5 , the partition plate is provided with a mounting hole, the valve assembly 16 comprises a valve cover plate 1601, a valve seat 1602 with a through hole, and an elastic member 1603, the through hole of the valve seat 1602 is installed in alignment with the mounting hole, the valve cover plate 1601 is connected with the valve seat 1602 in an openable and closable manner through the elastic member 1603, the opening and closing degree of the valve cover plate 1601 under different exhaust pressures is controlled through the elastic force of the elastic member 1603, and the opening and closing of the valve assembly 16 is controlled through the opening and closing of the valve cover plate 1601. The opening angle of the valve cover plate 1601 is related to the pressure difference of the valve cover plate 1601, and the greater the opening angle, the greater the elastic force of the elastic member.
[0035] The valve assembly 16 can be directly and independently fixed on the partition plate, or the partition plate itself structure can be used as a valve seat, and the elastic member and the valve cover plate are directly placed on the partition plate, that is, the entire partition plate serves as a bypass valve mechanism.
[0036] In the embodiment, the elastic member 1603 is a torsion spring, the torsion spring is arranged on a shaft 1604, the shaft 1604 is installed on the valve seat 1602, one end of the torsion spring abuts against the valve cover plate 1601, and the other end of the torsion spring abuts against the valve seat 1602. The valve cover plate 1601 is opened and closed under the elastic force of the torsion spring around the shaft 1604.
[0037] As shown in Figures 3 to 4As shown, the gas outlet and the lower section of the mixing pipe 13 are provided with a gas baffle 17, the gas baffle 17 closes a part of the gas outlet, the gas baffle 17 is provided with a plurality of third openings, so that the mixed gas is discharged through the area of the gas outlet which is not closed by the gas baffle and the third openings of the gas baffle 17.
[0038] In the adjustable end cover integrated mixer, the gas baffle is additionally arranged between the gas outlet and the lower section of the mixing pipe, which can effectively adjust the gas uniformity index and ammonia uniformity index of the SCR end face, and can effectively prevent the urea liquid or crystals from passing through the mixer part from the bottom to the SCR end face to block the SCR catalyst.
[0039] As shown in the drawings, Figure 3 The gas baffle 17 is a semicircular plate structure, and the semicircular plate structure matches the profile of the lower half of the gas outlet to close the bottom of the gas outlet.
[0040] As shown in the drawings, Figure 3 The nozzle 2 is installed in the first opening 20 through the nozzle mounting seat 12. The first opening 20 is provided with a sealing plate 11 to install the nozzle mounting seat 12, and the mixing pipe 13 passes through the opening of the sealing plate 11 to realize that the nozzle sprays the reducing agent into the mixing pipe 13.
[0041] As shown in the drawings, Figures 3 to 4 The end cover housing 10 has a longitudinal axis, the longitudinal axis of the end cover housing 10 passes through the open end 19 and the closed end, and the longitudinal axis of the mixing pipe 13 is perpendicular to the longitudinal axis of the end cover housing 10. The central axes of the first opening 20 and the second opening 21 are both perpendicular to the longitudinal axis of the end cover housing 10, and the first opening 20 and the second opening 21 are both arranged on the side wall of the end cover housing 10. The mixing pipe 13 can also be arranged in a non-perpendicular state in the inner cavity of the end cover housing, for example, inclined at an angle of 60°-120°.
[0042] As shown in the drawings, Figure 3 And Figure 4 The part of the open end 19 corresponding to the first cavity 18 is closed by the partition plate 15.
[0043] Specifically, the partition plate 15 has a plate body, the plate body is provided with a mounting hole for the mixing pipe 13 to pass through, and the partition plate 15 has an extension part extending from the plate body towards the first cavity 18, and the part of the open end 19 corresponding to the first cavity 18 is closed by the extension part.
[0044] As shown in the drawings, Figure 3As shown, the mixing pipe 13 comprises a cyclone pipe with cyclone vanes 14, the upper part of the cyclone pipe is provided with a plurality of vane windows, the plurality of vane windows form the inlet of the mixing pipe 13, and when the gas enters the mixing pipe 13 through the vane windows, the gas forms a rotating shape, and the bottom opening of the cyclone pipe is the outlet of the mixing pipe 13. Based on the vane windows and the cyclone vanes of the cyclone pipe, the adjustable end cover integrated mixer of the utility model forms high-efficiency cyclone inside, and the performance is excellent. The side wall of the cyclone pipe can be perforated, and the vanes in the vane windows can be inward or outward.
[0045] The adjustable end cover integrated mixer and the corresponding post-processing system of the utility model utilize the end cone at the inlet of the existing post-processing system, integrate the design of the mixer, have high integration degree, compact space, low back pressure, good mixing effect, excellent anti-crystallization performance, and under the preset pressure, the valve assembly is opened to directly bypass part of the high-temperature gas, so that the effect of controlling the overall back pressure is achieved; under the preset high load, the valve assembly is opened, and the high-temperature exhaust gas is wrapped outside the mixing pipe to heat the mixing pipe, so that the crystallization can be effectively reduced and eliminated; the opening and closing of the valve assembly can effectively reduce the generation of crystallization, can generate more ammonia gas to carry out the reduction reaction with nitrogen oxides; through the opening degree control of the valve assembly, the gas flow and ammonia gas distribution of the gas outlet can be adjusted, the uniformity index of the gas and ammonia gas before SCR can be effectively improved, and then the reduction reaction capacity with nitrogen oxides is improved.
[0046] In this specification, the utility model has been described with reference to its specific embodiments. However, it is obvious that various modifications and changes can be made without departing from the spirit and scope of the utility model. Therefore, the specification and drawings should be considered as illustrative rather than restrictive.
Claims
1. An adjustable end cap integrated mixer characterized by, The end cover shell has an open end, a closed end opposite to the open end, and a side wall between the open end and the closed end, the open end is used to connect a pre-treater, a first opening and a second opening are respectively arranged on the side wall of the end cover shell, the first opening is used to mount a nozzle, and the second opening is an air inlet of a mixer, an inner cavity of the end cover shell is provided with a mixing pipe and a partition plate, the mixing pipe is arranged in the inner cavity of the end cover shell through the partition plate, the inner cavity of the end cover shell is divided into a first cavity and a second cavity by the partition plate, all tail gas enters the first cavity through the air inlet of the mixer, the mixing pipe has an inlet for air and an outlet for air, the inlet of the mixing pipe is located in the first cavity, the outlet of the mixing pipe is located in the second cavity, and a part of the open end of the end cover shell corresponding to the first cavity is closed. The partition plate is provided with at least one valve assembly, and the at least one valve assembly is arranged to be in a closed state when the exhaust pressure is less than a preset pressure and in an open state when the exhaust pressure exceeds the preset pressure to form a bypass channel between the first cavity and the second cavity. When the at least one valve assembly is in the closed state, all tail gas entering the first cavity enters the mixing pipe through the inlet of the mixing pipe, mixes with a reducing agent in the mixing pipe, and is discharged through the outlet of the mixing pipe, the air outlet of the mixer, and the pre-treater; when the at least one valve assembly is in the open state, part of the tail gas entering the first cavity enters the mixing pipe through the inlet. Another part of the tail gas entering the first cavity enters the second cavity through the bypass channel formed after the valve assembly is opened and is discharged through the air outlet.
2. The adjustable end cap integrated mixer of claim 1, wherein, An air outlet baffle is arranged between the air outlet and a lower segment of the mixing pipe, the air outlet baffle closes a part of the air outlet, the air outlet baffle is provided with a plurality of third openings, so that mixed gas is discharged through the area of the air outlet which is not closed by the air outlet baffle and the third openings of the air outlet baffle.
3. The adjustable end cap integrated mixer of claim 2, wherein, The air outlet baffle is a semicircular plate structure which matches the contour of the lower half of the air outlet to close the bottom of the air outlet.
4. The adjustable end cap integrated mixer of claim 1, wherein, The partition plate is provided with a mounting hole, the valve assembly includes a valve cover plate, a valve seat with a through hole, and an elastic member, the through hole of the valve seat is aligned with the mounting hole and is mounted, the valve cover plate is connected to the valve seat in an openable and closable manner through the elastic member, the opening and closing degree of the valve cover plate under different exhaust pressures is controlled by the elastic force of the elastic member, and the opening and closing of the valve assembly is controlled by the opening and closing of the valve cover plate.
5. The adjustable end cap integrated mixer of claim 4, wherein, The elastic member is a torsion spring, the torsion spring is arranged on a shaft, the shaft is arranged on the valve seat, one end of the torsion spring abuts against the valve cover plate, and the other end of the torsion spring abuts against the valve seat.
6. The adjustable end cap integrated mixer of claim 1, wherein, The longitudinal axis of the mixing pipe and the longitudinal axis of the end cover shell form a preset angle, and the preset angle is 60°-120°; and the central axes of the first opening and the second opening are perpendicular to the longitudinal axis of the end cover shell.
7. The adjustable end cap integrated mixer of claim 1, wherein, The portion of the open end corresponding to the first cavity is closed by the partition plate, the partition plate has a plate body, the plate body is provided with a mounting hole for the mixing pipe to pass through, the partition plate has an extension part extending from the plate body towards the first cavity, and the portion of the open end corresponding to the first cavity is closed by the extension part.
8. The adjustable end cap integrated mixer of claim 1, wherein, The mixing pipe comprises a cyclone pipe provided with cyclone vanes, the upper portion of the cyclone pipe is provided with a plurality of vane windows, the plurality of vane windows form the inlet of the mixing pipe, and the gas enters the mixing pipe through the vane windows in a rotating mode; and the bottom end opening of the cyclone pipe is the outlet of the mixing pipe; and the nozzle is arranged in the first opening through a nozzle mounting seat.
9. An aftertreatment system characterized by, The adjustable end cover integrated mixer is arranged on the front processor as an end cover, and the front processor is a front SCR or a front ASC.
10. The aftertreatment system of claim 9, wherein, The rear processing system comprises a DOC, a DPF, a rear mixer, and a rear processor, the front processor is sequentially connected with the inlet of the DOC, the DPF, and the rear mixer, the outlet of the rear mixer is connected with the rear processor, the rear processor is a rear SCR or a rear ASC, and the central axis of the gas inlet of the adjustable end cover integrated mixer is perpendicular to the central axes of the inlet and the outlet of the rear mixer. The adjustable end cover integrated mixer is arranged on the front processor as an end cover, and the front processor is a front SCR or a front ASC. The rear processing system comprises a DOC, a DPF, a rear mixer, and a rear processor, the front processor is sequentially connected with the inlet of the DOC, the DPF, and the rear mixer, the outlet of the rear mixer is connected with the rear processor, the rear processor is a rear SCR or a rear ASC, and the central axis of the gas inlet of the adjustable end cover integrated mixer is perpendicular to the central axes of the inlet and the outlet of the rear mixer.