NOX REMOVAL PROCESS USING PULSED DISCHARGE PLASMA

Nonequilibrium plasma can be used to promote chemical reactions that reduce the emission of gaseous pollutants, such as NOx, produced by coal-burning power plants or by diesel engines, Laboratory experiments were carried out to study the decrease of NOx in simulated flue gases (initial concentration of NO: 200-800 ppm, O-2: 10%, N-2-balance gas) by means of a pulsed discharge plasma generated in a cylinder type reactor (outer electrode: 20-mm diameter), A rotating spark gap provided square wave high-voltages up to 25-kV, at a frequency of 250 Hz, to corona electrodes of 0.1-, 3.3-, and 6,4-mm diameter. The tests were performed at various temperatures (ambient to 220 degrees C) and constant residence time (0.6 s), The removal performance depended on the size of the discharge electrode and was better at room temperature, The addition of C2H4 significantly enhanced the removal performance, concentration of NOx decreased from 800 ppm to 300 ppm in the discharge, The by-products of this process were analyzed using infrared spectroscopy, No traces of toxic gases could be detected.