Numerical analysis of the electric field in plate-type electrostatic separators

The high intensity of the electric field of a plate-type electrostatic separator depends on the shape, size and relative position of the electrodes. An extended zone of quasi-uniform intense electric field may contribute to a significant improvement of the eletrostatic separation efficiency. In this paper, the analysis of the electric field was carried out using Prof. Levin's "Charge Simulation Program", which is based on the boundary element method and is provided with advanced pre- and post-processing capabilites. Several electric field configurations were studied. The circular profile tubular high-voltage ("active") electrode was shown to generate an intense electric field on only 2/3 of the grounded ("passive") electrode. Two cylindrical "active" electrodes might improve the situation. By using an ellipse profile tubular "active" electrode the resulted electric field was more uniform and the separation efficiency could be expected to increase. A good agreement was found between the theoretical predictions and the results of a simple experiment. A laboratory plate-type electrostatic separator was built in conformity with the design suggested by the results of this work. (C) 2000 Elsevier Science B.V. All rights reserved.