Ferrite solids for a heavy liquid suspension, method of preparation thereof and use of ferrite as heavy liquid solids

Method of preparation of a ferrite heavy liquid suspension filler, comprising comminution and mechanical classification of fractions, characterized in that it comprises steps of

• a) classifying a comminuted ferrite fraction of a waste material in a mechanical 0.2-2 mm classifier, to form a fine screened fraction and a coarse fraction,
• b) separating the fine screened fraction from step (a) in an electromagnetic separator with migrating magnetic field, where after separating a non-magnetic fraction, a ferrite fraction, which constitutes a filler for a heavy liquid suspension, is obtained,
• c1) comminuting the coarse fraction from the 0.2-2 mm classifier obtained in step (a) in a crusher, preferably a roll crusher,
• c2) classifying the comminuted fraction from step (c1) in a two-deck 2-5 mm and 0.2-2 mm classifier to form three fractions:
• finest screened ferrite fraction directed to the electromagnetic separator with migrating magnetic field along with the fine screened fraction from step (a), a coarser ferrite fraction, and coarsest fraction comprising a metallic fraction,
• c) comminuting the coarser fraction from step (c2), preferably in a fine grinding mill,
• d) recycling the fraction obtained in step (c) to the two-deck 2-5 mm and 0.2-2 mm classifier in step (c1), and
• e) removing the coarsest metallic fraction from the two-deck 2-5 mm and 0.2-2 mm classifier.