Particle capture efficiency in a multi-wire model for high gradient magnetic separation


Eisenträger, Almut
Vella, Dominic
Griffiths, Ian M.

KAUST Grant Number


High gradient magnetic separation (HGMS) is an efficient way to remove magnetic and paramagnetic particles, such as heavy metals, from waste water. As the suspension flows through a magnetized filter mesh, high magnetic gradients around the wires attract and capture the particles removing them from the fluid. We model such a system by considering the motion of a paramagnetic tracer particle through a periodic array of magnetized cylinders. We show that there is a critical Mason number (ratio of viscous to magnetic forces) below which the particle is captured irrespective of its initial position in the array. Above this threshold, particle capture is only partially successful and depends on the particle's entry position. We determine the relationship between the critical Mason number and the system geometry using numerical and asymptotic calculations. If a capture efficiency below 100% is sufficient, our results demonstrate how operating the HGMS system above the critical Mason number but with multiple separation cycles may increase efficiency. © 2014 AIP Publishing LLC.

Eisenträger A, Vella D, Griffiths IM (2014) Particle capture efficiency in a multi-wire model for high gradient magnetic separation. Applied Physics Letters 105: 033508. Available:

This publication was based on work supported in part by Award No. KUK-C1-013-04 made by King Abdullah University of Science and Technology (KAUST) and by Award No. 113/277 made by the John Fell Fund.

AIP Publishing

Applied Physics Letters


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