Evaluation of ilmenite as a possible medium in a dry dense medium fluidized bed

Abstract

Alternative dry coal beneficiation method is in high demand, especially in arid geographical environments. This dry process eliminates the need for water usage and there are suggestions that it has the benefits of high separation precision and quick return on investment. Current published dry dense medium separation work has mainly focused on using magnetite as a medium, but various complications have been encountered when magnetite was used. This study will extend the approach by investigating the use of ilmenite as an alternative medium for this dry dense medium fluidization process. The experiment was conducted on coal sized between 13-50 mm in a laboratory scale cylindrical fluidized bed, and density tracers were used to determine the Ecart Probable Moyen. The initial investigation considered a medium consisting of fine sand with ilmenite and fine coal with ilmenite. The results revealed that a uniform and stable fluidized bed can be achieved in both scenarios. At optimal conditions, the bed medium mixtures consisting of Ilmenite with fine sand and fine coal had a separation EPM of 0.045 and 0.05, and a cut density of 1.8 and 1.58g/cm3 respectively. Losses of ilmenite on coal were found to be 24.17 kg/t at external moisture of 4%.