Separation characteristics of dry high-intensity drum magnetic separator

Abstract

Dry high-intensity drum magnetic separator (DHIDMS) has been effectively used for the utilization of low-grade iron ores, thus an in-depth investigation on the separation characteristics of the DHIDMS separator would contribute to its design and practical operation. A numerical model was established to describe the particles motion in the DHIDMS process, on which the motion trajectories of siderite and quartz particles were simulated in the high and low magnetic field areas above the magnet surface, to reveal their dynamic behaviors; and the effects of two dominant operating parameters affecting the trajectory of particles, i.e., particle size and drum rotation speed, on the separation performance of a pilot-scale DHIDMS separator were investigated for a siderite ore. Simulation analysis indicates that the motion trajectories of the siderite and quartz particles are obviously different from each other in the high magnetic field area, but they generate negligible diversities in the low magnetic field area. In addition, in the high magnetic field area, the particle size and drum rotation speed significantly affect the distance between the motion trajectories of siderite and quartz particles, thereby affecting the separation selectivity of the DHIDMS separator. Experimental investigations indicate that, the feed particle size and drum rotation speed have definitely significant effects on the separation selectivity of the separator in the high magnetic field area; meanwhile, there is no separation selectivity for iron minerals in the low magnetic field area, thus deteriorating the recovery rate of iron concentrate. These results are basically consistent with the simulation analysis. This investigation has provided a general reference for the optimum design and operation of DHIDMS separator.