The behavior of a spherical particle under non-uniform electric field in silicone oil

In order to pursue a suitable electrode configuration removing solid impurities contained in liquefied plastic waste, a tilted plane electrode system is constructed and investigated. The edge part of plane electrodes was rounded for outer particle motion. The particle motion was observed by an ordinary CCD and a high-speed video camera. When high DC voltage is applied, a particle shows up-and-down motion. The particle usually moves either direction of the electrode depending on the applied voltage. When the applied voltage is relatively low, it moves toward the narrower gap side and as the voltage is high enough, it moves toward the wider gap side. At the particular voltage, the particle shows steady up-and-down motion at the middle of the plates. Another interesting result observed is the stationary hemi-circular motion of a particle at the electrode edge. The duration of upward motion is much longer than the downward motion. These results suggest that particles can be separated by particle size and voltage by using these characteristics.