MEHRSTUFIGE SORTIERVORRICHTUNG ZUM SORTIEREN VON FESTSTOFFGEMISCHEN

An apparatus for sorting lightweight from heavy material in mixtures of solid materials containing lumpy, granular, and pulverous constituents substantially comprises an upright slim container having a lower portion into which material for sorting is introduced. Pulsating air flows are introduced from the exterior into the container, resulting in an upward flow of pulsating air which loosens the material for sorting and produces a fluidized bed. Simultaneously, the apparatus is vibrated up and down in a linear manner by vibrators to assist in loosening the material. The lightweight material floating in the air stream is conveyed to a discharge channel at the top end of the container, whereas heavy material rapidly sinks down to a tubular member into which a second pulsating air flow is introduced in order additionally to sort the heavy material in a last treatment stage inside the tubular member. Any fine material present passes through a screen into a collecting container from which it is blown out through a short pipe. A weight-dependent circuit periodically opens a closure device at the outlet of the tubular member so that heavy material that has accumulated therein can exit downwardly.