Abstract: Aiming at the magnetic and mechanical inclusions existing in the traditional wet low intensity magnetic separator,a vertical permanent magnetic separator with three products is developed.The machine is mainly composed of the upper feeding system,outer vertical tube,vertical weak magnetic inner drum with rotating magnetic system,the grizzly setting between outer and inner cylinder,the surface of which is perpendicular to the cylinder surface,overflow tank located in the upper part of the outer barrel,back-wash water pipe and outlet discharge of both middlings and concentrate located at the bottom of outer barrel,racks,drive system,and control system i.e.Its separation principle is:with the effect of rotating magnetic system,materials in sorting area,between outer and inner cylinder,will conduct centrifugal circular motion,polyethylene formed by magnetic or mechanical inclusions will be scattered when impacting with the grizzly.Single magnetite particles move to the magnetic system and gradually enter into the concentration tank with the impact of magnetism and gravity.Locked particles move departure the magnet system and gradually into the middlings slot with the impact of centrifugal and gravity force.Nonmagnetic gangue particles flow into the overflow tank as tailings with the impact of back-washing water.Cleaning tests were conducted on the feeding of magnetic column in Nanfen Dressing Plant with 65.35% iron.Iron grade of final iron concentrate obtained is 68.78%,fairly with the concentrate gained from the on-site magnetic column,at the same time,middlings with yield of 10.86% and iron grade of 49.08% and tailings with yield of2.97% and iron grade of 25.54% are achieved.The results indicate that,the design principle of vertical permanent magnetic separator for cleaning with three products is feasible,but the Fe grade of tailing is a bit higher.Further research and improvement should be continued.

Key words: Vertical permanent magnetic separator for cleaning with three products, Rotating magnetic system, Grizzly, Magnetite, Cleaning