Key Benefits

  • High gold recovery with fluidised cones
  • Robust and easy maintenance
  • Flexible operations

Unsurpassed gold recovery with the Knelson Semi-Continuous Gravity Concentrator

The Knelson Semi-Continuous Gravity Concentrator is synonymous with industry-best gravity gold recovery, fine gold recovery and recovery of precious metals.

It is highly configurable and available in a range of model sizes that will suit any hard rock or alluvial mining operation. With capacity range from laboratory scale up to 1000 tonnes of solids per hour, it combines centrifugally enhanced gravitational forces with a fluidised bed process to provide exceptional recovery of precious metals such as gold, silver and platinum group metals.


The concentrator utilises a rotating assembly featuring advanced concentrate cone technology for optimal metallurgical performance.


This unit includes a one-piece upper frame and tailings launder assembly along with a robust lower frame designed to improve access and simplify maintenance. A free-standing, remote mounted piping is also provided for installation flexibility.

Our latest development of the Knelson GX cone delivers a culmination of 40-plus years of research and operational experience

At the heart of our gravity separation technology is the Knelson concentrating cone. The new patented GX model delivers impressive recovery enhancements. By incorporating an advanced distribution of fluidisation water across the entire concentrating cone, the Knelson GX facilitates the highest possible recovery of coarse and fine gold.
Knelson™ Semi-Continuous Gravity Concentrator

Balanced flow between ring sections

Zone separator nozzles in the GX cone regulate the amount of fluidisation within each ring. Control of the fluidisation water flow results in improved recovery throughout the entire cone, an innovative step change in metallurgical performance.
Knelson™ Semi-Continuous Gravity Concentrator

Tangential water distribution

Tangential introduction of water into the concentrating rings improves the distribution of fluidised water, avoiding rat-holing and dead spots, as it also allows thorough flushing of the unit without use of expensive and unnecessary variable-frequency drives. 

Specifications for Knelson Concentrators

Knelson™ GX Concentrating Cone
The Knelson Semi-Continuous Gravity Concentrator offers robust design for long life and high availability. This product will not only meet your expectations but consistently exceed them.

An easy-to-maintain gravity separation system that maximises gold recovery

We pride ourselves on having products that stand out from our competitors. As such, the quality and performance of our Knelson Semi-Continuous Gravity Concentrator is hard to beat.

High gold recovery with fully fluidised cones

Our concentrator’s leading-edge cone technology has been built on 40 years of innovation and is designed to capture the maximum amount of gold per cycle. Knelson is the only enhanced gravity concentrator with a fully fluidised bed allowing for upgrading throughout the entire cone surface.

Reduces maintenance efforts
With the increased wear life of these new reclaimer components, we have also effectively increased maintenance intervals. Our new maintenance-friendly designs and tools result in easier exchanges of components.
Robust and easy maintenance

The product is designed to be easily accessible, with fewer parts and an automated greasing system. Unit internals are rubber lined to process abrasive material with ease and minimise wear. The design is built from high-quality materials. Stainless steel parts have been used to upgrade the latest design, offering you better value and longer service life.

Flexible operations

Unlike competitors, Knelson concentrators can operate on feed densities of up to 75% solids, meaning that it can be installed in multiple different locations within the process, making the system more versatile.

A fully optimised design for optimum gold recovery

Our Knelson Semi-Continuous Gravity Concentrator is leaps and bounds ahead of competitors when it comes to equipment features and design. With precise equipment enhancements, the unit not only provides the highest possible gold recovery than anything else on the market, but it has been intentionally built to have fewer moving parts, making it an efficient machine that’s easier to maintain.

Knelson™ Semi-Continuous Gravity Concentrator

Smoother operation

Similar products on the market face vibration problems if the feed is not diluted before entering the machine. However, you will never face this problem with Knelson concentrators. Refined unit design has allowed the unit’s center of gravity to be lowered and the machine load to be hung rather than supported from below, eliminating overall vibration.


Few parts

The Knelson Concentrator has been designed with a reduced number of parts, simpler construction and reduced manufacturing time. These measures have reduced the cost of maintenance without  impacting its industry-best recovery and capacity. The latest generation of concentrators further enhances reliability and efficiency.

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