TRANSACTION PAPER

 

Investigation into how the magnesia, silica, and alumina contents of iron ore sinter influence its mineralogy and properties

 

 

M.K. Kalenga^I; A.M. Garbers-Craig^II

^IDepartment of Extraction Metallurgy, Faculty of Engineering, the Built Environment, University of Johannesburg, South Africa
^IIDepartment of Materials Science and Metallurgical Engineering, Faculty of Engineering, the Built Environment and Information Technology, University of Pretoria, South Africa

 

 

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SYNOPSIS

The influence of varying amounts of magnesia, silica, and alumina in iron ore sinter on its mineralogy, reducibility index (RI), reduction disintegration index (RDI), physical breakdown (AI and TI), and production properties (coke breeze rate) were examined.
It was found that the mineralogy of iron sinter can more easily be predicted from its chemical composition than from the RI, RDI, AI or TI. Anticipating the consequence that varying amounts of MgO and SiO₂ would have on sinter properties is complex, and not necessarily predictable. High concentrations of Al₂O₃ in the sinter result in high concentrations of the SFCA phase, but with drastically deteriorated properties. This study also confirmed that the form in which fluxes are added to the raw material sinter mixture affects the mineralogy and properties of the produced sinter.

Keywords: Iron sinter, mineralogy, reducibility, reduction degradation, abrasion index, tumble index

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Paper received Nov. 2008
Revised paper received Jun. 2010