SCR urea mixer

Abstract

The invention discloses an SCR urea mixer. A front baffle is arranged in a shell, a rear baffle is arranged at the rear side of the front baffle, and the left side and the right side of the rear baffle are covered with side baffles; the rear baffle and the side baffles at the two sides divide a cavity, located at the rear side of the front baffle, in the shell into an inner cavity with an open bottom face; and a first pore plate, a second pore plate and a first flow guide plate which are arranged at intervals are sequentially arranged in the inner cavity from top to bottom. The inner cavity is divided into a plurality of areas, airflow flows in the multiple areas, and urea liquid drops are decomposed and mixed multiple times in the multiple areas, so that the mixing uniformity of ammonia gas is improved, the conversion rate of NOx is further improved, and the overall performance of catalyst is guaranteed; The decomposition and mixing of urea liquid drops are carried out in the inner cavity, and the inner cavity has a heat preservation effect, so that it is guaranteed that the wall faces of all parts in the inner cavity have a high temperature, the urea liquid drops can fully absorb heat and volatilize, the urea crystallization risk is reduced, and the conversion rate of the NOx is increased.

Description

technical field [0001] The invention relates to the technical field of aftertreatment of engine exhaust gas, in particular to an SCR urea mixer. Background technique [0002] In the engine exhaust after-treatment system, the selective catalytic reduction technology (SCR) is usually used to post-treat the engine's exhaust emissions; A mixer is added in the mixer, and urea aqueous solution is sprayed into the mixer, and the urea aqueous solution is decomposed into ammonia gas (NH 3 ), under the action of catalyst, ammonia (NH 3 ) to remove the nitrogen oxides (NO X ) reduced to harmless nitrogen (N 2 ) and water (H 2 O), and finally discharged from the exhaust pipe, so as to achieve the purpose of reducing emissions. [0003] The existing post-treatment urea mixer has a high risk of crystallization, poor mixing uniformity of ammonia gas, and poor conversion efficiency of nitrogen oxides, which may easily cause part of the ammonia to escape, thereby affecting the overall p...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the disadvantages of high crystallization risk and poor ammonia mixing uniformity of the above-mentioned post-treatment urea mixer, the applicant provides an SCR urea mixer with a reasonable structure, which has low crystallization risk and high ammonia mixing uniformity

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