Urea mixer for tail gas treatment

Abstract

The utility model relates to the technical field of automobile tail gas treatment, in particular to a urea mixer for tail gas treatment, which comprises a mixing cylinder, a Z-shaped partition plate is arranged in the mixing cylinder, the mixing cylinder is divided into a gas inlet chamber and a gas outlet chamber by the partition plate, a communicated conveying pipeline is arranged between the gas inlet chamber and the gas outlet chamber, and the gas inlet chamber is communicated with the gas outlet chamber. The conveying pipeline is connected with the side wall of the mixing cylinder, a urea injector facing the gas inlet chamber is arranged on the outer wall of the mixing cylinder, a circular grid plate is arranged at the position, located at the gas outlet chamber, of the mixing cylinder, and a carrier is arranged in the conveying pipeline. When tail gas is exhausted outwards through the circular grid plate, the circular grid plate can play a role in uniformly distributing the tail gas, the tail gas can be uniformly dispersed when passing through the circular grid plate, and the tail gas uniformly dispersed through the circular grid plate can be better mixed with other substances, so that the condition of local non-uniform mixing is avoided, and the tail gas can be uniformly dispersed through the circular grid plate. And the situation that the local flow speed of the airflow in the pipeline is too high or too low can be avoided.

Description

Technical Field

[0001] This utility model relates to the field of automotive exhaust gas treatment technology, and in particular to a urea mixer for exhaust gas treatment. Background Technology

[0002] Currently, selective catalytic reduction (SCR) technology is commonly used in engine exhaust aftertreatment systems. Urea aqueous solution is injected into the exhaust aftertreatment mixer, and under the action of a catalyst, nitrogen oxides (NOx) in the exhaust gas are reduced into harmless nitrogen (N2) and water (H2O), thereby reducing emissions.

[0003] However, existing exhaust gas treatment methods can only discharge the gas from a single location, which can cause excessive urea solution in the discharged gas and result in uneven discharge of the mixed exhaust gas, leading to poor mixing effect. Utility Model Content

[0004] To solve the above problems, this utility model provides a urea mixer for exhaust gas treatment, the specific technical solution of which is as follows:

[0005] A urea mixer for exhaust gas treatment includes a mixing cylinder with a Z-shaped partition plate inside, dividing the mixing cylinder into an inlet chamber and an outlet chamber. A conveying pipe is provided between the inlet and outlet chambers and is connected to the side wall of the mixing cylinder. A urea injector facing the inlet chamber is provided on the outer wall of the mixing cylinder. A circular grid plate is provided at the outlet chamber of the mixing cylinder. A carrier is provided inside the conveying pipe.

[0006] Furthermore, the conveying pipe has several equally spaced openings at one end of the air inlet chamber, and inclined guide plates are provided at the openings.

[0007] Furthermore, the conveying pipe is provided with several exhaust ports at one end of the exhaust chamber.

[0008] Furthermore, the partition plate has a snap-fit ​​cylinder at the exhaust port, and the cylinder has a notch, which is located on the side away from the circular grid plate.

[0009] Furthermore, the mixing cylinder is provided with an inlet flange and an outlet flange at both ends.

[0010] Furthermore, the intake flange is provided with two injection channels, and the injection end of the urea injector is located within the two injection channels.

[0011] Beneficial effects: In the process of mixing exhaust gas and urea, the exhaust gas enters the intake chamber and is then transported to the outlet chamber through a conveying pipe. During this process, the exhaust gas and the carrier are fully mixed, resulting in a better reaction effect. Finally, the exhaust gas is directed towards the cylindrical shape and then flows towards the circular grid plate. When the exhaust gas is discharged outward through the circular grid plate, the circular grid plate plays a role in uniformly distributing the exhaust gas. The presence of the circular grid plate allows the exhaust gas to be evenly dispersed as it passes through, enabling it to mix better with other substances and avoiding uneven mixing in certain areas. It also prevents the airflow from being too fast or too slow in certain areas within the pipe. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of this utility model. Figure 1 ;

[0013] Figure 2 This is a schematic diagram of the overall structure of this utility model. Figure 2 ;

[0014] Figure 3 This is a cross-sectional view of the present invention;

[0015] Figure 4 This is a schematic diagram of the conveying pipeline of this utility model installed on the partition plate;

[0016] Figure 5 This is a three-dimensional structural diagram of the conveying pipeline of this utility model;

[0017] Reference numerals: 1. Mixing cylinder; 11. Divider plate; 12. Inlet chamber; 13. Outlet chamber; 2. Conveying pipe; 21. Opening; 22. Guide plate; 23. Exhaust port; 3. Carrier; 4. Circular grid plate; 5. Cylinder; 51. Notch; 6. Inlet flange; 7. Outlet flange; 8. Injection channel. Detailed Implementation

[0018] The embodiments of this disclosure will be further described in detail below with reference to the accompanying drawings and examples. The detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of this disclosure by way of example, but should not be used to limit the scope of this disclosure. This disclosure can be implemented in many different forms and is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0019] Reference Figures 1 to 5This embodiment proposes a design for a urea mixer for exhaust gas treatment, including a mixing cylinder 1. The mixing cylinder 1 is provided with a Z-shaped partition plate 11, which divides the mixing cylinder 1 into an inlet chamber 12 and an outlet chamber 13. A conveying pipe 2 is provided between the inlet chamber 12 and the outlet chamber 13. The conveying pipe 2 is connected to the side wall of the mixing cylinder 1. A urea injector facing the inlet chamber 12 is provided on the outer wall of the mixing cylinder 1. A circular grid plate 4 is provided at the outlet chamber 13 of the mixing cylinder 1. A carrier 3 is provided inside the conveying pipe 2.

[0020] The carrier 3 is a cordierite ceramic carrier 3. Cordierite has a low coefficient of thermal expansion, which allows it to maintain structural stability in environments with frequent changes in exhaust gas temperature. Its honeycomb structure can provide a large specific surface area, providing sufficient reaction sites for the reaction between ammonia produced by urea decomposition and nitrogen oxides in the exhaust gas.

[0021] The carrier 3 is a silicon carbide ceramic carrier 3: The silicon carbide SiC ceramic carrier 3 has good thermal conductivity and high-temperature strength. Its high thermal conductivity facilitates the rapid transfer of heat in the carrier 3, allowing the reaction to proceed in a relatively uniform temperature field. In the high-temperature exhaust gas treatment process, the silicon carbide carrier 3 can withstand higher temperatures and resist corrosion from chemicals in the exhaust gas, which helps to extend the service life of the carrier 3.

[0022] During the mixing process of exhaust gas and urea, after the exhaust gas enters the intake chamber 12, it is transported to the outlet chamber 13 through the conveying pipe 2. During this process, the exhaust gas and the carrier 3 are fully mixed, resulting in a better reaction effect. Finally, the exhaust gas is directed towards the cylinder 5 and then flows towards the circular grid plate 4. When the exhaust gas is discharged outward through the circular grid plate 4, the circular grid plate 4 plays a role in uniformly distributing the exhaust gas. The presence of the circular grid plate 4 can make the exhaust gas evenly dispersed when passing through. The exhaust gas, after being evenly dispersed by the circular grid plate 4, can better mix with other substances, avoiding uneven mixing in some areas and preventing the airflow from being too fast or too slow in some areas of the pipe.

[0023] Preferably, the conveying pipe 2 has a plurality of equally spaced openings 21 at one end of the air inlet chamber 12, and an inclined guide plate 22 is provided at the opening 21.

[0024] The mixture of exhaust gas and urea is conveyed to the conveying pipe 2 through the opening 21. A guide plate is provided at the opening 21. The shape and angle of the guide plate can be designed to cause the mixture to rotate or otherwise flow internally, thereby enhancing the mixing of exhaust gas and urea and making the urea more evenly distributed in the exhaust gas. The guide plate can extend the residence time and flow path of the mixture near the opening 21, thereby improving the mixing effect.

[0025] Preferably, the conveying pipe 2 is provided with a plurality of exhaust ports 23 at one end of the exhaust chamber 13; the partition plate 11 is provided with a snap-fit ​​cylinder 5 at the exhaust port 23, the cylinder 5 is provided with a notch 51, and the notch 51 is located on the side away from the circular grid plate 4.

[0026] After the exhaust gas is mixed, it is discharged outward through the outlet on the conveying pipe 2. At this time, the cylinder 5 will block the exhaust gas discharged outward, while the position of the notch 51 allows the exhaust gas to be transported into the exhaust chamber 13. The notch 51 is set on the side away from the circular grid plate 4, which can prolong the residence time of the exhaust gas in the exhaust chamber 13, so that the exhaust gas and urea are mixed better.

[0027] Preferably, the mixing cylinder 1 is provided with an inlet flange 6 and an outlet flange 7 at both ends; the two ends of the mixing cylinder 1 are respectively connected to the existing device through the inlet flange 6 and the outlet flange 7, thereby fixing the position of the mixing cylinder 1.

[0028] Preferably, the air inlet flange 6 is provided with two injection channels 8, and the injection end of the urea injector is located within the two injection channels 8.

[0029] When the urea injector works, it injects urea into the intake chamber 12 through two injection channels 8, thereby achieving urea injection from two directions, making the urea and exhaust gas mix more evenly.

[0030] The technical principles of this utility model have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this utility model without inventive effort, and these embodiments will all fall within the protection scope of the claims of this utility model.

Claims

1. A urea mixer for exhaust gas treatment, characterized in that, The system includes a mixing cylinder (1), which is provided with a Z-shaped partition plate (11) that divides the mixing cylinder (1) into an air inlet chamber (12) and an air outlet chamber (13). A conveying pipe (2) is provided between the air inlet chamber (12) and the air outlet chamber (13). The conveying pipe (2) is connected to the side wall of the mixing cylinder (1). A urea injector facing the air inlet chamber (12) is provided on the outer wall of the mixing cylinder (1). A circular grid plate (4) is provided at the air outlet chamber (13) of the mixing cylinder (1). A carrier (3) is provided inside the conveying pipe (2).

2. The urea mixer for exhaust gas treatment according to claim 1, characterized in that: The conveying pipe (2) has several equally spaced openings (21) at one end of the air inlet chamber (12), and the openings (21) are provided with inclined guide plates (22).

3. The urea mixer for exhaust gas treatment according to claim 1, characterized in that: The conveying pipe (2) is provided with several exhaust ports (23) at one end of the air outlet chamber (13).

4. A urea mixer for exhaust gas treatment according to claim 3, characterized in that: The partition plate (11) is provided with a snap-fit ​​cylinder (5) at the exhaust port (23). The cylinder (5) is provided with a notch (51), which is located on the side away from the circular grid plate (4).

5. A urea mixer for exhaust gas treatment according to claim 1, characterized in that: The mixing cylinder (1) is provided with an inlet flange (6) and an outlet flange (7) at both ends.

6. A urea mixer for exhaust gas treatment according to claim 5, characterized in that: The air intake flange (6) is provided with two injection channels (8), and the injection end of the urea injector is located in the two injection channels (8).

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