Strengthening liberation and separation of magnetite ore via magnetic pulse pretreatment: An industrial test study

Performing ore pretreatment before grinding is particularly crucial for improving mineral liberation and conserving energy. This study proposed an innovative magnetic pulse pretreatment (MPP) technology that primarily used the magnetostrictive effect in an alternating magnetic field to enhance mineral liberation. The effect of MPP on the liberation degree and magnetite separation for magnetite ore were systematically investigated. The results show that the size and volume of the magnetic mineral particles in the ore due to the stretching effect of the alternating magnetic field resulted in microcracks at the interface between different minerals. Compared with the unpretreated process in an industrial test, increment in the −0.043 mm content of the ball mill discharge increased by 3.33 percentage points, increment in the liberation degree of magnetite across the entire particle size range increased by 5.82 percentage points, and increment in the iron concentrate grade increased by 1.22 percentage points, with an error range of 0.1%, due to MPP. The industrial application of MPP brings an enormous economic benefit potential to iron ore utilization.