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The thickening process is the primary method of producing high solids slurries for the minerals industry.
Thickener outputs can accommodate a range of tailings disposal options from low yield stress, easily
pumped suspensions for disposal in conventional ‘wet’ tailings dams to more concentrated slurries for
delivery to ‘dry disposal’ and backfill applications. The thickening process, although operated successfully
in a large range of sites around the world, is poorly understood and predictive design of thickening devices is
still empirical. Although predictive models of thickening do exist, the correlation to reality is often poor and
there is a desperate need to bring the two together to make rational improvements to thickener design and
operation. Therefore, whilst some would dismiss the models as being unacceptable for predictive design,
they are very useful in formulating expected operational trends and providing an understanding of the
directions one should take in improving operational performance. The aim of this article is to bring together
model, laboratory and in-field results to elucidate the state of the art in understanding thickener operation
from first principles.
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