Concentrates produced from MnO2 and Fe203 ore fines have been
targeted as potential feedstocks for direct metallurgical processing.
Prereduction of pyrolusite-rich Mn02 sands to MnO has been investigated
in batch and continuous experimental bubbling fluidised beds using
CO-H2 reducing gas mixtures. This process has been found to produce a
high grade feedstock suitable for smelting to ferroalloys or acid digestion
for chemicals production. Similarly, production of highly metallised
direct reduced iron (DRI) from hematite ore fines has also been
investigated in batch bubbling bed reactors. Programs to characterise the
reduction kinetics, fluidisation behaviour and defluidisation phenomena
for both feedstocks are currently in progress to enable optimum process
conditions to be determined.