Gravity concentration breakthrough improves recovery, cuts downtime

Knelson semi-continous gravity concentrator. Credit: FLSmidth

For decades, Knelson gravity concentrators have been the gold standard for recovery of gold and precious metals. FLSmidth’s latest innovation in semi-continuous gravity separation is the new Knelson GX concentrating cone, which delivers a key breakthrough in performance that increases recovery and cuts maintenance downtime.

The patented GX Cone delivers impressive recovery enhancements due to enhanced water distribution within each ring. As water enters from the base, it flows through zone separator nozzles for a customizable fluidization profile. This allows for even distribution of water in each ring; the new design also significantly increases the active recovery surface area. The result is a step change in overall coarse and fine gold recovery. Test data shows that gold recovery in all size fractions, from course to fine, improved significantly with the GX Cone.

By incorporating an advanced distribution of fluidization water across the entire concentrating cone, the Knelson GX facilitates the highest possible recovery of coarse and fine gold. Balanced water distribution across the concentrating cone allows for a significant reduction in fluidisation water requirements while improving recovery.

The third major benefit of the Knelson GX is easier maintenance. Because it is made of a customized, abrasion-resistant and durable polyurethane compound, maintenance frequency and operational costs are significantly reduced.

“The new Knelson GX concentrating cone is the culmination of over 40 years of research and operational experience and is exciting news for our customers: it delivers a win-win-win scenario: better recovery, less water use and less downtime due to easier maintenance. In short, it helps customers produce more with less resources – a central tenet of our MissionZero ambition to cut water and energy waste in mining by 2030,” Mike Lefler, head of global product line manager for precious metal recovery at FLSmidth, said in a release.

FLSmidth provides sustainable productivity to the global mining and cement industries.

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