| 摘要 |
<p>PROBLEM TO BE SOLVED: To efficiently remove the nitrogen oxides in the environment and to reduce a by-product at low cost by setting the applied voltage generating plasma wherein NO2 in gas becomes the maximum as a reference value in the case when the nitrogen oxides is to be removed by forming atmospheric pressure low temp. equilibrium plasma is waste gas. SOLUTION: Flow rates of the air incorporated from a compressor 2 and the sample gas made to flow out from a nitrogen oxides tank 4 are controlled respectively with each flow rate control valve 12 and 13 and mixed by using a flow rate regulating valve 5 so that a prescribed concn. may be obtained, then the obtained mixture is circulated to a plasma reactor 3. In such a case, the voltage applied to the plasma reactor 3 from an electrode 10 by interposing inner and outer electrodes is measured with a high voltage probe and an oscilloscope 9. And the concentration of NO and NO2, etc., in the sample gas are analyzed with an analyzing device 7. When NO in the waste gas is oxidized to NO2 by the formation of the plasma, the applied voltage forming the plasma is set based on an applied voltage at which NO2 becomes the maximum value.</p> |
