Dynamics of conductive and nonconductive particles under high-voltage electrostatic coupling fields

With the high-voltage electrostatic theory and numerical analysis, the dynamics of conductive and nonconductive particles under high-voltage electrostatic coupling fields was studied. The oscillation behavior of the conductive particle between the corona electrode and ground electrode was analyzed and its oscillation amplitude was S _m=(t _a +t _s ) · v _m/2. It was found that there was the “lift-off voltage (U _lo)” for the conductive particle between the electrostatic electrode and ground electrode. The concepts of “critical charged rotational speed (n*)”, “detaching critical rotational speed of nonconductive particle (n′)” and “ratio of voltage and distance between surface of electrodes (U/D)” were presented and their criteria were established. The trajectories of the conductive particles under the coupling fields of the corona electrode, electrostatic electrode and ground electrode were simulated by the computer. The simulative results were in good agreement with the experimental ones. This research enriches the high-voltage electrostatic theory and provides a theoretic basis for optimization of operating parameters and structure design of high-voltage electrostatic separator. Supported by the National High Technology Research and Development Program of China (“863” Program) (Grant No.2006AA06Z364), Program for New Century Excellent Talents in University (Grant No. NCET-05-0404) and the Research Fund for the Doctoral Program of Higher Education of China (Grant No.200060248058)