Particle charging in electric field under simulated SO3-containing flue gas at low temperature

Abstract

Particle and SO3 emitting from the processes of fuel combustion considerably deteriorate environment. Charging of particle in electric field was widely used for achieving effective removal of particle from SO3-containing flue gas in various industries. This study provided an insight into particle charging in electric field with presence of SO3 in terms of particle charging simulation and experiments under various conditions. Results illustrated that once temperature was below acid dew point, particle charge increased and then declined with the increasing concentration of SO3. Besides, sulfuric acid aerosol transformed from gaseous SO3 was enhanced by higher electric field strength and temperature, but this increase seemed to be limited when reached maximum. Meanwhile, electrode optimization could enhance charging by improving ion density, which charge of particle with 0.04 μm and 1.22 μm was increased by 3.53 and 1.16. Moreover, improving dielectric constant and electric field strength mainly acted on charging of larger particle, whereas improving ion density determined small particle charging. As for medium-sized particle, simultaneously combining electric field strength and ion density adjustment to enhance particle charging was effective. Find suggested that different parameter adjustment methods should be selected according to particle diameter to enhance particle charging and reduce particle emission of SO3-containing flue gas.