In this study, we aim to construct a new separation system for plastics using the magnetic Archimedes effect under high magnetic field gradient with less environmental impact and lower cost. In the levitation experiment, a newly manufactured monopole electromagnet was used. It has the features of being able to perform levitation experiments in an open space above ferromagnetic arrays generating high magnetic field gradient. In the magnet design, the distance between monopole electromagnet and ferromagnetic case, the shape of ferromagnetic case and the ferromagnetic arrangement of the central part were optimized to enhance the magnetic flux densities. Using the monopole electromagnet and the superconducting magnet, levitation experimental studies for several kinds of plastic were carried out. Three kinds of plastic balls were submerged in the bottom of an acrylic pipe filled with MnCl2 (20 wt. %) and levitated by applying a magnetic field. 19 ferromagnetic arrays were inserted in the magnet upper bore, and they were levitated at 10 mm for POM and 38 mm for PC shown in Fig1. In addition, the shape of the magnet lid and the arrangement of the ferromagnetic body constructing magnets were optimized by using a COMSOL electromagnetic analysis simulation software. These results suggest that sufficient resolution can be ensured in the levitation of plastics using this system.

Keywords: magneto-Archimedes effect, plastic levitation, magnetic separation