Charging and diffusion collection of aerosol nanoparticles less than 20 nm in electrostatic precipitator

摘要

It has been of importance to capture submicrometer aerosol particles in relation to environmental contaminations and there,in special,has been of a renewed interest in the harmful health effects of ultrafine nanoparticles.Electrostatic precipitators (ESP) are widely used for the collection of pollutant aerosol particulates in industrial sites and many experimental studies have been widely conducted for the collection efficiency of micrometer and submicrometer particles in ESPs (Zhuang et al.,2000;Kulkarni et al.,2002).However,the behavior of nanoparticles especially less than 20 nm in diameter in ESPs has beer unclear.For smaller particle size,charging probability decreases,and thus,the collection efficiency also decreases.However,particle diffusion becomes unavoidable for the nanoparticles in this size range,resulting that particle capture in ESPs may increase.Therefore,the competition between these two opposing effects will dominate the collection efficiency of the ESPs.In this study,we report an investigation for the collection of aerosol nanoparticles (< 20 nm) in an ESP according to charging and diffusion effects.