Collection of submicron particles by an electrostatic precipitator using a dielectric barrier discharge

Although dielectric barrier discharge (DBD) in air has been used to clean hazardous air pollutants (HAPs) because of its high electron density and energy, its potential use as precharging dust aerosol particles is not well known. In this work, we measured the size distributions of bimodal submicron aerosol particles and estimated the collection efficiency of the particles for a hybrid two-stage electrostatic precipitator (ESP) comprised of a DBD charger as the particle charger and an ESP as charged particle collector. Nano-sized particles of NaCl (30-100 nm) and DOS (50-800 nm) were generated by evaporation-condensation and atomization, respectively. Various electrical and flow conditions were applied on the DBD charger: AC applied voltage of 9-11 kV, frequency of 60-120 Hz, and air flow rate of 60 - 180 L min^{- 1} (0.048 - 0.016 s of particle residence time). The particle collection efficiencies increased as the AC applied voltage increased at a fixed frequency-flow rate, whereas the efficiencies decreased as the frequency and flow rate increased at a fixed AC power-flow rate and a fixed AC applied voltage-frequency.