Urea mixing device for tail gas after-treatment

Abstract

The invention discloses a urea mixing device for tail gas after-treatment. A gas inlet cylinder and a gas outlet cylinder are connected through a connecting section, a rear shell is fixed to one side of the gas inlet cylinder, the connecting section and the gas outlet cylinder, an inner cavity is defined by the connecting section and the rear shell, the gas inlet cylinder and the gas outlet cylinder are communicated with the inner cavity, and a transverse partition plate and a flow guide plate are transversely arranged on the inner side of the rear shell up and down; a gap is formed between the transverse partition plate and the flow guide plate; a mixing outer pipe is inserted into the transverse partition plate, and a mixing inner pipe and a crushing plate which are arranged up and down are arranged in the mixing outer pipe. After tail gas flow and urea liquid drops are mixed, the tail gas flow and the urea liquid drops flow through the multi-layer crushing structure, so that the urea liquid drops are crushed to be smaller, more fully and more easily disturbed by the gas flow, the gas flow and the urea liquid drops are fully mixed in multiple mixing cavities, the mixing effect is better, the urea mixing uniformity is higher, and the urea crystallization risk is lower.

Description

technical field [0001] The invention relates to the technical field of automobile tail gas post-treatment, in particular to a urea mixing device for tail gas post-treatment. Background technique [0002] At present, in the engine exhaust aftertreatment system, selective catalytic reduction technology (SCR) is usually used for aftertreatment. The urea aqueous solution is sprayed into the exhaust aftertreatment mixer. Under the action of the catalyst, the nitrogen oxides in the exhaust will be (NO X ) reduced to harmless nitrogen (N 2 ) and water (H 2 O), to achieve the purpose of reducing emissions. [0003] The urea mixing uniformity of the existing urea mixing device is poor, and it is easy to form urea crystals, which affects the performance of the post-treatment system, and what's more, it will cause excessive emission or blockage of the post-treatment system, resulting in insufficient power of the vehicle. Contents of the invention [0004] Aiming at the above-ment...

AI Technical Summary

Problems solved by technology

[0003] The urea mixing uniformity of the existing urea mixing device is poor, and it is easy to form urea crystals, which affects the performance of the after-treatment system, and even causes excessive emissions or blockage of the after-treatment system, resulting in insufficient vehicle power

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