Journal of the Southern African Institute of Mining and Metallurgy
versão On-line ISSN 2411-9717
MUTHAPHULI, P. Production of pelletizing concentrates from Zandrivierspoort magnetite/haematite ore by magnetic separation. J. S. Afr. Inst. Min. Metall. [online]. 2014, vol.114, n.7, pp. 505-510. ISSN 2411-9717.
Kumba Iron Ore's Zandrivierspoort (ZRP) magnetite-haematite project aims to mine and beneficiate a magnetite resource with low contaminant levels to produce from 1 Mt/a to 2.5 Mt/a product, which will be either a concentrate, micro-pellets for direct reduction, or blast furnace pellets. Anglo American Technical Solutions Research conducted a number of piloting campaigns to validate the process design flow sheet, demonstrate process performance, and to generate data for use as a design basis. Secondary to this, the pilot plant was to produce approximately 7 t of magnetite-haematite concentrate with low enough SiO2 to be used as feedstock for pelletizing studies. The pilot plant achieved 34.2% mass yield, at 69.0% Fe, 2.2% SiO2, from an IsaMill grind of 80% -45 µm. This product quality will compare favourably to other leading direct reduction (DR) pelletizing concentrates. However, two-stage comminution to 80% -75 µm and beneficiation of ZRP ore will produce a blast furnace (BF) quality pelletizing concentrate, indicative quality being 67.6% Fe and 4% SiO2, at higher mass yields. An economic evaluation between producing a DR and a BF pelletizing concentrate will have to be conducted prior to finalizing the concentrate production flow sheet.
Palavras-chave : Magnetic separation; iron ore; magnetite; haematite.