New electrostatic precipitator with dielectric coatings to efficiently and safely remove sub-micro particles in the building environment

The influx of ambient particulate matter (PM) to the indoor environment has threatened human health due to its adverse impacts on respiratory, cardiovascular, and neurological systems. Consequently, PM removal devices with high efficiency and low cost like electrostatic precipitator (ESP) are essential for a healthy and sustainable indoor environment. Traditional two-staged ESP includes particle charging and collection part. In this study, we innovated the collection part by coating the repelling electrodes with dielectric films. Four performance influencing parameters were examined: the voltage difference (V-c) and distance (d(c)) between the repelling and collecting electrodes, and both the dielectric material and thickness (d(e)). The new ESP achieved its best performance when coated with PET (d(e) =60 mu m) at d(c) =3 mm. The breakdown voltage was promoted from -4 kV (without dielectric film) to -9 kV, and PM removal efficiency was enhanced from 60 % to 92 %. The new ESP had low net ozone production (3-5 ppb), low pressure drop (10-13 Pa), and low energy consumption (18 W/m(2)), making it an eco-friendly device. Running continuously for one week, the new ESP maintained a single-pass PM removal efficiency of around 90 %, notwithstanding changes in ambient air temperature and relative humidity.