Method for electrostatically separating a granule mixture made of different materials, and device for implementing same

Abstract

A method and a device for electrostatically separating polyvalent granular insulating materials that have good properties, are energy efficient, and easily adapt to ambient atmospheric conditions and to physiochemical properties of the granules to be separated. The method includes: a) injecting a current of air between two electrodes in a separation chamber defined by walls and having an air inlet and outlet; b) placing the granule mixture, made of different materials, into the air current; c) controlling the air current so that the granules levitate in the air current in a turbulent mode and become electrically charged by contact therebetween and/or by contact with the walls of the separation chamber; d) generating an electric field between two electrodes, substantially perpendicular to the direction of the air current, such that the charged granules in c) move, either in the direction of the electric field if the granules are positively charged or in the opposite direction if the charge thereof is negative; e) adhering the charged granules to the surface of the electrodes; and f) discharging and collecting the granules adhering to each electrode.