| 摘要 |
<p>PURPOSE:CO-free, NOx-containing waste gas is added with hydrogen and hydrocarbon and treated in a specific range of temperature in the presence of oxygen, thereby to increase NO oxidation ratio, enhancing NO2 removal efficiency. CONSTITUTION:Substantially CO-free, NOx-containing waste gas from heating furnace or the like is added with hydrogen or hydrocarbon such as propane in a quantity of one or more moles or preferably 5 or more moles per one mole of NO in the waste gas. The mixed gas is maintained at 450 to 750 deg.C for more than 0.05 seconds in the presence of oxygen in sufficient amount to oxidize hydrogen and hydrocarbon into H2O and CO2 where NO in the waste gas is oxidized into NO2. The formed NO2 is absorbed by wet type absorber such as NaOH. In this process, NO in the waste gas is nearly completely oxidized into NO2, providing means for an easy and high ratio NOx removal.</p> |
