Effect of magnetic pulse preprocessing on iron ore

Magnetite ore from Dagushan was pretreated by magnetic pulse.The cracks and fissures within the ore were generated at the interface of different minerals,which improved the grinding efficiency and separation index of the magnetite.The testing results showed that the content of -0.074 mm in the ground product increased 0.25%~2.4% after preprocessing by magnetic pulse with the magnetic intensity of 39.81kA/m.The grade of iron concentrate increased 0.41%~2.43% and the recovery increased 0.55%~1.81% after pretreatment under appropriate condition of grinding-magnetic separation.Furthermore,the microstructure of raw materials and the liberation degree of the grinding products before or after pretreatment were investigated by means of biological microscope and the scanning electron microscope,respectively.The function mechanism of magnetic pulse pretreatment improving the grinding efficiency and separation index of iron ore was explained.