Red mud is produced as a by-product during the hydrometallurgical production of alumina (Al2O3) from aluminum ore – bauxite. In master's thesis were investigated the possibility of extracting weakly magnetic hematite with High Gradient Magnetic Separation (HGMS) and the possibility of extracting heavy minerals (hematite, rutile, zirconium) by Enhanced Multi Gravity Separator (EMGS). The above-mentioned separation methods were applied for the first time on red mud. The investigated material was taken from the Birač red mud landfill, alumina factory Alumina d. o. o. Zvornik, Bosnia and Herzegovina. The aim of the testing was to define suitable production conditions for the production of pre-concentrates of trace elements Sc, Y, La, Ga, REE in hematite for their further hydrometallurgical extraction, as well as for the production of concentrates of heavy titanium minerals (rutile) and zirconium from the non-magnetic fraction of red mud. Based on the laser analyzer, it was determined that the average fraction of red mud is about 10 μm. Based on the results of XRF analysis, it was determined that gravity separation was most successful on the 25–45 µm fraction for hematite and for zirconium at a specific material density of ρ = 1.03. The gravity separation for rutile was not successful on all mentioned fractions. Magnetic separation was most successful on the 25–45 µm fraction for hematite at the magnetic field density ρ = 3,6 kG. It has been proven for the first time that with the used methods of magnetic separation and concentration of weakly magnetic hematite in the initial phase and the final gravitational separation of titanium minerals and zirconium from the non-magnetic fraction of red mud, that red mud shows good potential for further profitable industrial production of titanium minerals and zirconium. In the next planned phases, we plan to the possibility of testing trace elements (Sc, Y and REE) bound to weakly magnetic hematite concentrate by chemical extraction.
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