Combined Electron Beam and Microwave Treatment for Flue Gas Purification

Abstract

The results of a research program concerning the application of the electron beam EB) irradiation, microwave MW) irradiation and simultaneous electron beam and microwave EB + MW) irradiation for removing nitrogen oxides NOX) and sulfur dioxide SO2) in simulated Due gases are presented. Several microwave applicators and reaction chambers used for NOX and SO2 removal tests are also presented. The additional use of MW energy and EB energy or the use of MW energy only proved to be a promising method for removal of pollutants in view of the reduction of power consumption and flue gas treatment process cost. Experiments performed at lower temperature 65-70°C) of the gaseous mixture air, Argon up to 7%, H2O up to 25%, CO2 up to 10%, SO2 up to 2000 ppm, NOX up to 1000 ppm, NH3 added in stoichiometric amounts) demonstrated a higher SO2 removal efficiency with lower absorbed dose. Promising results are obtained especially for SO2 removal efficiency: up to 80% for MW, 85% for EB irradiation and up to 90% for EB + MW irradiation. A considerable amount of SO2 can be separated even without MW, EB or EB + MW irradiation due the spontaneous reaction with ammonia at gaseous mixture temperature below 70°C. The most important conclusion concerning MW irradiation is that efficiency of removal of pollutants strongly depends on microwave applicator structure type, residence time and MW power level.