Electrostatic free-fall separator

Claim 1

An electrostatic free-fall separator for separating mixtures of materials having low electrical conductivity, particularly mineral material mixtures, the electrostatic free-fall separator comprising inlet means for feeding a material to be separated; outlet means for withdrawing the material after having been separated and including separating flaps located underneath said inlet means; means for separating the material, located between said inlet means and said outlet means and including at least two rotatable roller-shaped field electrodes arranged parallel to and at a distance from one another and generating a substantially horizontally directed electrical high-voltage field, said roller-shaped field electrodes being formed as cylindrical hollow bodies having a predetermined diameter, two ends formed as semi-spherical caps without edges and of one-piece with a remaining portion of the same hollow body, and horizontally directed longitudinal axes located at the same height parallel to one another, said hollow bodies which form said electrodes being spaced from one another by a relatively small distance which is at most equal to the diameter of said electrodes; and stripping means arranged outside of the electric field generated between said field electrodes.