A review of principles and applications of magnetic flocculation to separate ultrafine magnetic particles

Abstract

Liqun Luo, Anh V Nguyen / A review of principles and applications of magnetic flocculation and separation of ultrafine magnetic particles 2 H I G H L I G H T S • The principles of magnetic separation have been critically reviewed; • Both external and interparticle forces for ultrafine particles are reviewed and compared; • Suspensions stability of the particles factors are described and analyzed; • Various modeling of magnetic flocculation are introduced and some of the applications are illustrated. Liqun Luo, Anh V Nguyen / A review of principles and applications of magnetic flocculation and separation of ultrafine magnetic particles 3 A B S T R A C T Magnetic separation has been used in industries to concentrate or remove magnetic minerals/particles for many years. The separation of ultrafine magnetic particles is significantly influenced by aggregation between particles due to various external and interparticle forces, such as gravity, magnetic attraction, van der Waals, electrical double-layer, hydrodynamic, and Brownian diffusion forces. This review focuses on the principles of the magnetic flocculation and separation of micrometer-sized particles in solution. Potential energies between particles are linked to the particle aggregation (i.e. stability), sedimentation and dispersion in applied magnetic fields. Prediction and control of magnetic flocculation are achieved by simulating particle motions around the surface of the magnetic separators using various mathematical models, with some large-scale applications of magnetic flocculation are being demonstrated.

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Preparation and recovery of iron carbide from pyrite cinder using carburization-magnetic separation technology

“…However, the increasing grinding fineness also results in the size drop of iron carbide particle. Fine particles cause the aggregation easily, which leads to the decrease of the iron recovery rate in magnetic separation [37]. When the size fraction continues to increase, both the iron content and iron recovery rate show downtrends, due to the enhanced particles aggregation.…”

A Preliminary Investigation into Separating Performance and Magnetic Field Characteristic Analysis Based on a Novel Matrix

“…The first two ways are more closely related to magnetic field distribution of separation space and the latter one may be accomplished by changing the surface hydrophilic property of feebly magnetic minerals under the action of surfactants. Some basic research can be found on selective hydrophobic or magnetic flocculation [13][14][15][16][17]. However, complex procedures of forming suitable floccules make it difficult to hold steady running in the production of mineral processing.…”