GB215935A - Process and apparatus for the magnetic separation of materials - Google Patents

Abstract

215,935. Rushen, P. C., (Krapp Grusonwerk Akt.-Ges., F.). April 25, 1923. Magnetic separators. - In a magnetic separator of the drum type, the material is passed through two or more annular magnetic fields, which are substantially equal in strength or which increase in strength outwardly in such a manner that the material is delivered through the outer field or fields to the innermost field where the main separation takes place, the material not acted upon being forced by gravity or centrifugal force through the outer fields where subsidiary separation takes place. Inside a drum 2 are arranged stationary magnets 3 provided with knife-edges 4 forming the primary pair of poles, and on the drum annular poles 5 with tapered or undercut edges 6, the poles 5 being axially adjustable to vary the strength of the outer field. The material is fed bv a delivery shoot extending into the inner field or extending between the poles 5 where a preliminary separation takes place. A plurality of fields may be provided by fitting rings 8, Fig. 4, provided with knife-edges 9, or by the provision of endless bands of magnetic or partly magnetic material running over the drum, the edges of the bands opposite each other forming the fields.