(652e) Self-Cleaning Electrostatic Oil Mist Collector By Using Corona Discharge and Surface Dielectric Barrier Discharge

Oil mist emitted during cooking is a major source of PM in the urban area. As its high efficiency and low pressure drop compared to other methods, ESP (Electrostatic Precipitator) is the most commonly used in the removal of oil mist. However, by long time operation with ESP, oil mist would be deposited on the surface of electrode. Particle deposition on electrode would reduce the particle removal efficiency of ESP. Therefore, ESP requires regular cleaning to maintain its initial performance. As cooking oil fume is very sticky when it’s deposited, it is very hard to be removed. To solve this problem, non-thermal plasma can be used to remove oil mist deposition on its electrode. In this study, we developed self-cleaning ESP using SDBD (Surface Dielectric Barrier Discharge) plasma. SDBD plasma is one of non-thermal plasma generated by high voltage AC or pulsed DC power. In the plasma region, there are lots of active species (radicals, electrons). These active species can decompose oil mist deposited at the surface of electrode.

Similar to conventional ESP, our device uses corona discharge for particle charging and DC electric field for particle collection. After long time operating in particle collection, the electrode needs cleaning because of the oil mist deposition. In this condition, by modifying the power circuit, SDBD plasma is generated at the surface of its electrode. By SDBD plasma generated at the surface, oil mist deposited on the electrode is decomposed to form gas phase products (CO, CO₂).

By increasing the applied voltage from 0 to 5 kV, particle collection efficiency also increased from 21% to 94.4%. After particle collection, our device works in electrode cleaning mode by using SDBD plasma. After operating SDBD plasma on the contaminated electrode, CO and CO₂ were detected at the outlet. Simultaneously, oil mist deposited at the surface was removed after operating SDBD plasma. From this result, it can be concluded that oil mist at the surface of the electrode was converted to CO and CO₂ by SDBD plasma.