Flue gas conditioning by in situ oxidation of so 2 applying dielectric barrier discharge

An advanced flue gas conditioning technology was developed through in situ oxidation of SO 2 using dielectric barrier discharge and heterogeneous condensation of SO 3 on fly ash (FA). Orthogonal experiments were carried out for the design of discharge structure, whereas the optimal condition was achieved at 8 kV of discharge voltage, 2 mm of discharge gap and 56 cm 2 of discharge area; single factor experiment was introduced here to investigate impacts of various elements (gas flux, temperature, concentration of SO 2 and relative humidity) on oxidation of SO 2 , results showed that the oxidation of SO 2 was in inverse proportion to gas flux and SO 2 concentration, whereas in direct proportion to relative humidity, the optimal temperature was detected at 45 °C. Physical and chemical characterizations of treated samples were performed in this work using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). Particle coagulation was found in the SEM, and a continuous peak rise of sulfate at 1086 cm −1 was detected by the FTIR analysis, which indicated that SO 3 generated by in situ oxidation of SO 2 could be successfully absorbed by the surface of FA particles. The specific resistance of conditioning FA showed a remarkable decrease from 1.41 × 10 13 to 5.74 × 10 11 Ω cm compared with the untreated sample. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.