Characterisation of Banded Iron Ore

摘要

A recently discovered Banded Iron Formation (BIF) deposit on the outskirts of a village called Matsitama in the Central part of Botswana, remains unexploited due to inadequate knowledge of its mineralogy and economic value. Currently, Botswana relies on imports in order to satisfy all its iron and steel needs. Exploitation of the Matsitama iron deposit is of critical importance from a socio-economic point of view. To assess the viability and sustainability of potential economic exploitation of the deposit, characterization studies must be conducted on the ore. In this study, chemical and mineralogical examinations were carried out. Mineralogical examination was performed using X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and specific gravity by pycnometer techniques were employed in this investigation. QEMSCAN technology was used to assess bulk mineralogy (BMA) and provide Particle Map Analysis (PMA) of the ore. Major minerals analysis by XRD revealed that Matsitama iron ore is mainly composed of 54.40% hematite, 44.00% quartz, 1.10% magnetite and 0.50% goethite minerals. XRF analysis established that the ore contains 55.9% Fe_2O_3 and 44.2% SiO_2, with minor amounts of Al_2O_3, Cr_2O_3, P_2O_5 and TiO_2 elements. QEMSCAN analysis indicated that 75% ofthe hematite is fully liberated, with 25% associated with quartz. Characterization results showed Matsitama ore to be a low hematite grade contaminated with silica and low concentration of deleterious elements (<1%) which conform to generally acceptable limits for commercially traded iron ores.