Optimal conditions for indoor air purification using non-thermal Corona discharge electrostatic precipitator

Cold plasmas improve indoor air quality by reducing fine and ultrafine particles threatening human health. Electrostatic precipitator (ESP) uses non-thermal corona discharge connected to negative DC high voltage needles with grounded parallel plate collectors. In this paper, a simulation of an ESP model is performed using COMSOL Multiphysics software to study optimal conditions for indoor air purification. Numerical results of current voltage distribution display a great correlation with experimental data. The corona current density, potential, electric field strength and density of space charges are investigated. Various geometric and operating parameters are utilized to investigate the ultrafine particles removal efficiency. Moreover, the collection efficiency and migration velocity are discussed according to particle size. ESP performance is affected by number of discharging wires as well as electrode size and configuration. A 94 % efficiency rate of removing particles from 0.01 to 0.25 µm radius is achieved under optimal conditions (40 kV, 1 m/s inlet velocity, five needles). In hence, controlling airborne particles through electrostatic precipitator technology under these optimal conditions has been proven to be reliable to remove ultrafine particles.