Enhanced Collection Efficiency of Nanoparticles by Electrostatic Precipitator with Needle-Cylinder Configuration

Nanoparticles produced in industrial processes are conventionally removed by electrostatic precipitators (ESPs). These ESPs usually have an electrode-collector with a wire-cylinder or wire-plate configuration. We designed an ESP with a needle-cylinder configuration and compared its collection performance with that of a conventional ESP. Our ESP exhibited a corona inception voltage of around 3 to 4 kV, which was significantly lower than that of the conventional ESP. The efficiency with which it could collect NaCl particles, which were used as model nanoparticles, was 98% at -5 kV. Unlike with a conventional ESP, soft X-ray irradiation reduced the collection efficiency, probably as a result of the recombination of the positive and negative ions. The corona power ratio was 0.024 W/lpm at a collection efficiency of 98%, showing that our new design produced an extremely efficient ESP. An ESP with a needle-cylinder configuration could be used to collect nanoparticles from a wide range of processes.