Magnetic particle capture in high-gradient magnetic separation: A theoretical and experimental study

Abstract

High-gradient magnetic separation (HGMS) has traditionally been used in mineral processing, with many effective models developed for typically employed rod-wire shaped matrices. However, its potential in bioprocessing, especially for high-value products, introduces new demands on plant and matrix design. This study presents a multi-scale model for HGMS that simulates new complex geometries, which enhance particle recovery. We have developed microscopic models to accurately simulate the trajectories of magnetic particles within the fluid flow and magnetic fields of HGMS systems. A pivotal aspect of our work is the effective translation of microscopic relationships into macroscopic transport models. The model is validated experimentally using a rotor-stator HGMS system tailored for bioprocessing, with magnetic particle concentration measurements showing strong alignment with the model's predictions. The model's flexibility enables its application across various matrix shapes, overcoming the limitations of traditional rod-wire models, and providing a robust framework for improved HGMS in-silico process understanding and optimization.