Electrostatic separation

Electrostatic separation techniques exploit the electrical conductivity differences of particles after charging and the appearance of positive or negative charges on their surface. The method of charging varies depending on the equipment and the application. A system of attraction or repulsion proportional to this charge enables their separation. The materials must be dry.

Eddy currents are caused by an alternating magnetic field generated by a polar device (alternating magnet wheel) rotating in a conveyor drum. They cause a repulsion of elements which drive electricity (especially aluminium, copper and magnesium).

Conventional electrostatic separators submit particles to ionic bombardment generated by a very high voltage electrode (15 to 30 kV). These charged particles come into contact with a grounded drum and discharge at different rates depending on their conductivity, thereby enabling their separation.

Triboelectric separators use an intensive friction charging method of the particles, some charging positively and others negatively. This technique therefore enables the preferential sorting of binary particle mixtures. This is almost exclusively reserved for sorting plastics (for example HDPE/PP, PET/PVC, PVC/rubber, PP/PS, ABS/PMMA, HIPS/ABX, PVC/PE and other mixtures).

CTP uses 3 techniques:

Equipment	Scale	Input	Capacity
Eddy current separator	Pilot	8-50 mm	50-250 kg/h
Electrostatic separator	Laboratory	100 µm to 10 mm	50 kg/h
Triboelectric separator	Pilot	2-10 mm	500 kg/h to 1 t/h