Hydrogen selective catalytic reduction device and control method thereof

Abstract

The invention provides a hydrogen selective catalytic reduction device and a control method thereof. The device comprises a high-pressure gas storing device, a filtering device, a pressure reducing device, a flow measuring device, an electrical control unit, a performer and various sensors. The electrical control unit judges the working status of a motor and extraction flow based on the signals of the sensors such as intake pressure, intake temperature, the location of an air throttle, rotary speed, top center, oxygen concentration and the like, measures the concentration of NOx in the front discharge pipe of the catalyzing device by an NOx sensor, judges the ejecting impulse width of hydrogen based on the pressure and temperature of a hydrogen supply system and adjusts the hydrogen ejecting volume based on the concentration of collected NOx in the rear discharge pipe of the catalyzing device, thus ensuring the transformation efficiency of NOx reaches the target control value and the ejecting timing of the ejected gas and the ejecting volume MAP are stored in the electrical control unit. The research results of the lean-burn natural gas motor show: the NOx transformation efficiency can reach 100 percent by ejecting hydrogen into the discharge pipe under different operational conditions of a motor.

Description

(1) Technical field [0001] The invention relates to a device for controlling harmful gas emission of an engine, and also relates to a control method of the device. Specifically relate to a hydrogen selective catalytic reduction (H 2 -SCR) device and control method. (2) Background technology [0002] The rapid development of the automobile industry has brought great convenience to people's production and life, but it has also caused serious oil shortages and environmental pollution problems. Countries around the world have successively formulated more and more stringent fuel economy and emission regulations. Automobile manufacturing In order to meet the requirements of these regulations and remain invincible in the fierce market competition, manufacturers actively develop engine energy-saving technologies, explore clean petroleum alternative energy sources, and develop efficient exhaust after-treatment devices. Diesel engines and ignition lean-burn engines have received gre...

AI Technical Summary

Problems solved by technology

Diesel engines and ignition lean-burn engines have received great attention from many countries because of their remarkable fuel-saving effects and good environmental performance. In order to make diesel engine emissions meet the requirements of future emission regulations, internal combustion engine workers have proposed various technical solutions. +The technical solution of Selective Catalytic Reduction (SCR) can effectively control NOx and PM emissions. The principle is that through the optimization of the combustion system, PM can be controlled during the combustion process, and the NOx emissions produced can be passed to the exhaust gas. Inject the blue solution with a concentration of 32.5% in the tube as a reducing agent for selective catalytic reduction, this method can make the NOx conversion efficiency above 85%; Ineffective, NOx emissions cannot be effectively controlled, so the SCR technology route similar to diesel engines can also be adopted, but there are some problems in using urea solution as a reducing agent, such as urea solution is corrosive to a certain extent, and has a pungent smell at the same time, adding The blue solution is easy to freeze when the temperature is lower than -11°C, so there will be some difficulties in application in cold regions, and additional heating is required

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