JOURNAL PAPER

 

Experiences in the production of metallurgical and chemical grade UG2 chromite concentrates from PGM tailings streams

 

 

N.F. Dawson

Xstrata, Rustenburg, South Africa

 

 

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SYNOPSIS

Recovery of a chromite concentrate from UG2 flotation tailings streams, of a grade suitable for further pyrometallurgical treatment for the production of ferrochrome, has certain specific challenges not only by virtue of the decoupled nature of the primary PGM recovery process and secondary gravity based chromite recovery circuits, but also because of intrinsic variations in the nature of the ore and its mineral composition. Variability in the ore, together with upstream process dynamics, creates a challenging environment in which to achieve optimal recovery of a gravity concentrate with accurate grade control. This paper examines certain interrelational aspects between the ore gangue and chromite mineral types, the influence of the primary PGM extraction circuit and secondary chromite extraction activity as applied specifically to UG2 ore against a background of actual plant experiences and circuit configurations applied in order achieve a suitable quality of chromite concentrate.

Keywords: UG2 chromite, spiral concentrators, chromite beneficiation

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