| 摘要 |
<p>Disclosed is an exhaust purifying device comprising a NOx reduction catalyst which is disposed in an engine exhaust pipe for reducing NOx with a liquid reducer such as an aqueous urea solution, a hot plate arranged in the lower part of the exhaust pipe in the exhaust upstream of the NOx reduction catalyst, an electrothermal heater built in the hot plate, a reducer-adding device for supplying the liquid reducer to the upper surface of the hot plate, and a control unit or thermostat for controlling the electrothermal heater so that the temperature of the hot plate is set at least the melting point of the reducer component or higher. By actively vaporizing and hydrolyzing the liquid reducer supplied to the upper surface of the hot plate, the reducer component can be effectively used while being prevented from precipitation.</p> |
