PURIFYING DEVICE FOR EXHAUST GAS BY PLASMA METHOD

摘要

PROBLEM TO BE SOLVED: To provide a plasma method purifying device for exhaust gas with the optimum electric power supply. SOLUTION: This device has such a constitution that high voltage pulses are continuously applied between a discharge electrode and a counter electrode to generate nonequilibrium plasma and that nitrogen oxides in the gas to be treated are made to react with radicals produced in the plasma so as to convert the nitrogen oxides into a form to be easily collected or into a harmless form. The electric power supply amt. is determined in such a manner that the amt. of ozone is 2 to 10 times as the nitrogen oxide density in the gas to be treated, which is based on the fact that the amt. of ozone as the index of radicals produced and the electric power supply are in a linear proportional relation and based on the relation between the ozone amt. and the reduction rate of the nitrogen oxide density in the gas as shown in the figure.