Desulfurization reaction of high sulfur content flue gas treated by electron beam

Hirosawa, Shojiro*; Kojima, Takuji; Hashimoto, Shoji; Suzuki, Ryoji*; Aoki, Shinji*

Experiments of flue gas treatment by electron beam were carried out, using simulated lignite-burning flue gas containing SO(5500ppm), NO(390ppm) and HO(22%). Removal efficiency of SO was more than 90% at a dose of 1-2kGy. It shows applicability of electron beam for treatment of lignite-burning flue gas. Another removal reaction besides the radiation-induced radical reaction and the thermal reaction occurring without irradiation was suggested by the facts that removal of SO by the radical reaction is only a few hundreds of ppm and the removal amounts by thermal reaction under irradiation is lower than a half of total desulfurization. The mechanism similar to thermal reaction was proposed, assuming simultaneous uptake reaction of SO and NH on the surface of liquid aerosol. It was suggested that ammonium nitrate having deliquescence relative humidity(DRH) of 60% at 25 plays an important role in producing liquid aerosols. Decrease of DRH of ammonium nitrate with increasing temperature and with formation of double salt of ammonium sulfate results in enhancement of formation of liquid aerosols.