Progress in SLon pulsating high gradient magnetic separation technology

Since pulsating high gradient magnetic separation(PHGMS) was proposed and put into application, it was achieved wide application in the history of HGMS development. This technology achieves high-efficient separation for weakly magnetic minerals in a pulsating slurry, which produces a loosing effect to particles wherein. On one hand, the pulsation of slurry prolongs the residence time and distance of particles passing through the magnetic matrix in the PHGMS separators, and thereby improves the separation performance considerably. On the other hand, the pulsation reduces the mechanical entrainment of non-magnetic particles into magnetic deposits on matrix, and avoids the clogging of matrix. The development of cylindrical matrix has furtherly pushed forward the industrialization of PHGMS technology, as it provides more sufficient and uniform passages for slurry passing through the matrix. In the past two decades, the PHGMS technology has significantly evolved from the theoretical aspects to industrial applications. The theoretical evolutions include the optimization design for magnet and matrix, which contributes to the innovative upgrading of the PHGMS separators, including its super scaling-up to meet the large-scale and low-cost separation of low-grade ores and tailings, high-magnetic induction design from matrix optimization theory for separation of extremely fine and weak magnetic minerals and for purification of non-metallic ores, with the separable particle size ranging from several microns up to six millimeters, so that its application is significantly extended for more minerals and larger particle size range. This paper summarized these theoretical and practical achievements, pointed out its drawbacks, and introduced several new HGMS technologies for overcoming these drawbacks. © 2024 Central South University. All rights reserved.