Electrostatic separation of brass from industrial wastes

Previous studies have demonstrated that electrostatic separation can be suc cessfully employed for the recycling of nonferrous metals from chopped elec tric wire and cable scrap. The aim of this paper was to investigate the pos sibility of using the electric field forces for the selective sorting of ot her granular mixtures, such as brass dress. Laboratory tests of electrostat ic separation were carried out on three samples: 0.08-1 mm, 0.08-0.2 mm, an d 0.2-1 mm, containing more than 66% of brass. Sample 1 was separated in a corona-electrostatic field, generated by a standard electrode arrangement: a grounded rotating roll electrode (diameter 150 mm) and two high-voltage e lectrodes (wire-type dual corona electrode + tubular electrode), Processing of the other two samples was carried out in a custom-designed separator co mprising an extended corona field generated between a matrix-type multineed le corona electrode and a roll electrode of large diameter (250 mm), Chemic al analysis of the products showed that more than 90% of the brass can be r ecovered with a purity higher than 95%, The extended corona field electrode arrangement proposed in this paper seems to be a promising solution for th e effective recycling of other granular wastes containing copper, aluminum, and their alloys.