Engine and double-whirl mixing device thereof

Abstract

The invention discloses an engine and a double-whirl mixing device thereof. The double-whirl mixing device comprises a mixing tube, a conical mixer and fan-type blades, wherein the mixing tube is used for mixing tail gas with urea; the conical mixer comprises a conical tube, an outlet end of which extends into the mixing tube, and a plurality of conical whirl plates which are arranged on the side wall of the conical tube and are distributed in the circumferential direction; the diameter of the inlet end of the conical tube is smaller than that of the outlet end of the conical tube; and the fan-type blades are arranged at the outlet end of the conical tube. In this way, the double-whirl mixing device provided by the invention can effectively avoid the problems that urea is easily deposited, is atomized poorly and is not mixed uniformly with the tail gas.

Description

technical field [0001] The invention relates to the technical field of tail gas treatment, and more specifically relates to an engine and a double swirl flow mixing device thereof. Background technique [0002] Selective catalytic reduction technology (Selective Catalytic Reduction, SCR) refers to the use of ammonia, ammonia water, urea or hydrocarbons as the reducing agent, under the condition that the oxygen concentration is more than two orders of magnitude higher than the NOx concentration, highly selective and preferential reduction of NOx for N2. The role of catalysis is to reduce the activation energy of the decomposition reaction and lower the reaction temperature to a suitable temperature range. [0003] Because urea is non-toxic, does not have a great impact on the environment and human health, and is convenient for storage and transportation, it is more suitable as a NOx reducing agent in the vehicle SCR system. [0004] Diesel vehicles with SCR systems tend to ...

AI Technical Summary

Problems solved by technology

During the operation of the vehicle, due to poor urea atomization, uneven mixing or insufficient decomposition, the sprayed urea droplets cannot be converted into NH3 in real time, but generate by-products, resulting in unstable reduction reactions, which affect the consistency of NOx emissions sex and conversion efficiency

[0005] Therefore, how to solve the problems of easy deposition of urea, poor atomization, and uneven mixing with tail gas in the tail gas treatment system in the prior art has become an important technical problem to be solved by those skilled in the art.

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