Tribocharging of granular plastic mixtures in view of electrostatic separation

The output of any electrostatic separation process is strongly dependent on the effectiveness of particle charging. A novel laboratory-scale fluidized-bed tribo-charging device has been described in a previous paper. The aim of the present work is to asses the effectiveness of two materials, aluminium and polypropylene, that could be employed for the manufacturing of the tribo-charging chamber of that device. The electrostatic separation experiments designed in this purpose were carried out on three samples of a granular polyethylene/polyvinyl chloride mixture, characterized by different compositions. Aluminium and polypropylene were found to be equally effective for the tribo-electrostatic separation of the 50% PVC, 50% PE sample. For the other two samples (10% PVC, 90% PE; 90% PVC110% PE), the best results were obtained with the polypropylene tribo-charging chamber.