Effect of ferromagnetic rods arrangement in high-gradient magnetic separator on the processing performance of weakly magnetic particles

Anshan style hematite ores was separated by a high-gradient magnetic separator,and the effect of rods arrangement,in which the rod gap and the rod diameter were same,on separation performance was investigated.The results showed that compared with separation performance using small rods arrangement(e.g.,2mm),concentrates grade and recovery improved using large rods arrangement(e.g., 4mm)at the feed fineness of-0.074mm<85%.The loss of metal content happened in tailings at the feed fineness of-0.074mm<85%,particularly using large rods.The forces of single mineral particles in the high-gradient magnetic field out of a single rod were investigated,and the magnetic force was two orders of magnitude higher than resultant of gravity and viscous resistance for-0.15+0.010mm size fraction particles.As rod diameter increased,magnetic capturing force on fine particles decreased and mechanical entraining of non-magnetic particles weakened.As a result,the separation performance improved.Resultant of gravity and viscous resistance are approximately equal to magnetic force for-0.010size fraction particles,and capture with rods on fine particles weakened.