Magnetic separation of fine particle dusts using a superconducting magnet and wire meshes

We have observed a phenomenon that flow patterns of gases are influenced by a magnetic field. To explain this phenomenon, a model called a ‘‘magnetic curtain’’ has been introduced. In this paper we apply this phenomenon to magnetic separation of fine particle dust in air. We use a superconducting magnet and fine ferromagnetic wires to obtain high magnetic field and high field gradient. Magnetic separation of fine particles is well realized. The efficiency of fine particle filtration increases with increasing magnetic field and also increases with particle size. The percentage of captured particles is 80% for particles larger than 1 μm, 60% for 0.5–1.0 μm, and 35% for 0.3–0.5 μm, respectively, when the field intensity is 4.5 T and the gradient is 1500 T/m.