FACTORS WHICH INFLUENCE THE INSULATION-METAL ELECTROSEPARATION

The experimental study of insulation-metal electroseparation as a multifactorial process has been performed by means of a console-type laboratory apparatus, with four high-voltage electrode carriers, interchangeable roll electrodes, and a set of collecting boxes. The paper illustrates how an electroseparator like this can be employed by research-, design- or application-engineers to investigate the role of each parameter or operating variable. It was revealed the influence exerted on the process by: (i) the homogeneity (composition, granulometric distribution) and the superficial moisture of the feed material; (ii) the positioning of the corona electrodes and the type of their emitting elements. A special study, based on a charge simulation program, was devoted to the shape, size and location of the electrostatic electrode. The interdependence between the electrical and mechanical factors, such as roll speed and roll radius, are distinctively discussed, with reference to an experiment made with a sample of chopped electric wire and cable scrap, containing stranded and massive copper, polyethylene and polyvinyl chloride. Several technical solutions suggested by the authors (corona electrodes with radially-orientated emitting wire segments, non-circular electrostatic electrode) have been adopted by the recycling industry.