Development of electrostatic separator using cylindrical electrodes

In this paper, the results of experimental and analytical studies of the performance of a new electrostatic separator for plastic mixtures for recycling are presented. The separator is of the free fall type and consists of four cylindrical electrodes. Prior to separation, plastic mixtures to be separated are tribocharged. When the charged particles are fed into the center of the space between the four electrodes, they are attracted to the space between the electrodes with voltages of polarity opposite to the particles" charge because of Coulomb force. Therefore, the plastic mixtures can be separated as a result of the different positions to which they fall. Separation tests were performed on a sample containing 50% polystyrene and 50% AB$ plastics. Plastic particles obtained from crushed plastic plates were used. It was found that the separation efficiency depends on the electric potential difference between positive and negative electrodes, tribocharging time, the rotation speed of the tribocharger and the length of the electrodes. It was also found that it is possible to obtain a high purity and a high recovery rate for a binary plastic mixture.