Key Benefits

  • Automated operating system
  • Easy maintenance
  • Versatile minerals recovery
  • High availability

Unparalleled metals recovery with the Knelson Continuous Gravity Concentrator

The Knelson Continuous Gravity Concentrator was developed to address specific mineral recovery applications which semi-batch-concentration methods are unable to achieve.

It is the only continuous gravity concentrator that utilises fluid-bed technology and avoids non-fluidised flowing film separation which, when used at higher G-forces, can cause dewatering and locking of particles.


The continuous gravity concentrator uses similar principles of mineral separation and recovery to that of the Knelson Batch Gravity Concentrator. However, the continuous technology differs by delivering a continuous stream of concentrate based on under defined settings. The concentrator will discharge the concentrate while simultaneously processing fresh feed, whereas batch units must be stopped intermittently to remove concentrate. A series of pinch valves, located at the base of the fluidised rings, are kept closed by air pressure. By releasing the air pressure periodically, concentrate can be ejected without an interruption in production.


With an automated control system, the operator interface also allows for live adjustments of operating variables such as fluidisation water flow, G-force and cycle time, which allows the product stream to be modified based on the plant requirements.

An automated continuous concentrating system for varying applications

With the combination of a strong customer focus and an advanced Knelson Continuous Gravity Concentrator, we are able to offer a range of benefits that are yet to be surpassed by any competing product.

Automated operating system

All continuous gravity concentrators are equipped with automated control systems to allow the concentrator to operate with minimal user involvement. A series of pinch valves, located at the base of the fluidised rings, are kept closed by air pressure. By opening the valves periodically, the concentrate is ejected without interrupting the machine’s operation.

Easy maintenance

These units have been built to be accessible and have parts that can be swapped out rapidly and easily. A mature valve design consisting of a cartridge type valve assembly enables the entire valve body to be quickly and easily changed-out, thus minimising any downtime. The original set of valves removed from the machine can then be re-fitted with a new set of replaceable sleeves allowing them to be ready for the next change-out interval. Other than this change out, routine lubrication is the most frequent maintenance task on the machine.

Versatile minerals recovery

Knelson Continuous Gravity Concentrator can be utilised for a broad range of gravity separation, recovery and upgrading applications. Along with recovering gold, these units can also recover or concentrate other PGMs, tin, industrial minerals, flotation concentrates and even separate ash from coal.

High availability
The rotating assembly is balanced with precision and housed in a frame with upper and lower frames separated by rubber vibration isolators. This unique design provides smooth and stable machine operation. The isolation of the upper and lower frames prevents disturbances caused by feed surges from affecting the unit’s mechanical structure resulting in high availability and efficient operations.

An application-specific automated continuous gravity concentrator

Knelson Continuous Gravity Concentrator has much to offer your plant. Not only is it available in a number of sizes, it can be tailored to operate as per the plant’s needs. Its features are truly unlike anything else on the market.

Size range

The continuous gravity concentrator is available in several sizes and configurations to suit a range of diverse applications; from the lab and pilot scale units to the world’s largest continuous gravity concentrator.


Operator interface

All machine functions are operated by a dedicated PLC via a touch screen HMI and will interface with the plant’s DCS system. Operating parameters such as fluidisation water flow, gravitational force, and pinch valve cycle times can be modified locally or remotely from the control room.

Automated fluidisation water flow

Fluidisation water is continuously supplied to the machine throughout the concentrating process to ensure the proper formation of the fluidised bed, resulting in appropriate particle separation and corresponding high target mineral recovery.

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