Commercial itabirite ores are commonly beneficiated by grinding...

Commercial itabirite ores are commonly beneficiated by grinding and flotation to liberate and remove silica from the feed ore with the remaining product being a high-grade hematite concentrate. Magnetic separation is generally not required for itabirite hematite. The preliminary flow sheet proposed for Mbarga comprises a two-stage grinding process. This is similar to that being developed by MMX for the Minas Rio project in Brazil. The fine concentrate product may then be transported either by rail or slurry pipeline to port (for instance, MMX are currently building a 525 kilometre slurry pipeline from mine to port, with the capacity to transport 26 million tonnes per annum of concentrate product). The process is commercially competitive as evidenced by significant production in Brazil. The concentrate produced in Brazil for export is either shipped direct to steel mills or pelletised prior to shipment. The process is technically straightforward and uses no new technology. The key issues are scale and cost. The cost is driven by the grain size and hardness of the feed ore which dictates the grind size and power demand.