Urea solution quick hydrolyzing device

Abstract

The invention relates to a urea solution quick hydrolyzing device which comprises a urea solution storing and pumping module, a urea solution hydrolyzing module, a NH3 ejecting module and a control module. The urea solution storing and pumping module comprises an urea tank (1) and a urea pump (2), the urea solution hydrolyzing module comprises a compression cylinder body (5), a urea solution ejector (4), a piston (7) and a crank-link mechanism (8) which drives the piston (7) to move, and the control module comprises a urea ejecting control unit DCU (10) which can collect the temperature and the NOx content of tail gas of an engine (13). The urea solution quick hydrolyzing device has the advantages that the actual temperature of a urea solution can be improved when the device changes the pressure and the size of the urea solution before the urea solution passes through a nozzle, the urea solution can all be hydrolyzed into NH3 and finally ejected into an exhaust pipe to be reacted with NOx in the tail gas on the surface of an SCR catalyst, and the problem of urea crystallization of the nozzle and the exhaust pipe is solved.

Description

Technical field [0001] The invention belongs to the field of engine NOx emission control, and specifically relates to a device that uses the law of thermodynamics to increase the temperature of a urea solution so that NH3 generated after the urea solution is rapidly hydrolyzed to reduce NOx. Background technique [0002] With the continuous tightening of air pollutant control regulations, the application of De NOx after-treatment catalysts is becoming more and more extensive, especially in the field of NOx emission control such as diesel vehicles and industrial denitrification. The usual practice is to install after the exhaust pipe. A set of Urea-SCR or NH 3 -SCR aftertreatment system to solve the problem of NOx emissions. Especially in the NOx emission control of motor vehicles, due to NH 3 It is difficult to store and has potential safety hazards. Urea-SCR has become the mainstream De NOx post-processing configuration. The general control principle is to store the urea soluti...

AI Technical Summary

Problems solved by technology

[0004] Since ammonia gas is relatively easy to obtain in industry, some engineers and technicians will consider using ammonia gas obtained in industry to store it through an ammonia gas storage tank, but this storage method needs to compress ammonia gas to increase the storage capacity. This will bring potential dangers such as compressed ammonia explosion, so it is rarely used in practice.

In addition, another type of research hotspot is the use of ammonia adsorption materials and devices to store ammonia. This technology relies on a kind of NH 3 Special materials with a large adsorption capacity are still in the research stage and cannot be put into use

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