Device and method for sorting a particulate stream

Abstract

The invention relates to a device for continuously sorting a particulate stream, comprising: a) a screw conveyor (1) for conveying the particulate stream to a separation device, b) a sieve (7) for separating the particulate stream ac cording to size, characterized in that it further comprises c) a pre-sieve (3) comprising elongated sieve openings formed by fingers extending towards an end portion of the pre-sieve with the tips of the fingers not being connected in that end portion, the pre-sieve (3) being located between the conveyor outlet and the sieve, d) wherein the pre-sieve (3) encloses part of the circumference of the conveyor screw in an axial end portion of the conveyor screw, and e) the radial distance between the conveyor screw (1) and the pre-sieve (3) is less than 10%, preferably less than 5% of the conveyor screw diameter. The pre-sieve allows to separate elongated objects like threads or wires from the particulate stream which would otherwise clog or block subsequent separation devices including the sieve.

Dependencies are inferred from the claim text.