Gravity Concentration

Falcon SB Series Gravity Concentrator

The Semi-Batch (SB) Gravity Concentrator

In the typical Falcon tradition, the Falcon Model ‘SB’ series of concentrators has been engineered with the simplicity of design, the efficiency of use and maximisation of results.

Even when other gravity recovery processes prove unsuitable, Falcon Concentrators are able to recover ultra fine liberated particles and make high-quality separations by utilizing a high gravitation field.

In some instances, a Falcon circuit can achieve as high as 80% of the overall plant production depending on the percentage of native metal present.

The Falcon Model ‘SB’ units work best for:

  • Free gold, silver and platinum recovery.
  • Grinding circuit cyclone u/f or feed.
  • Cleaning concentrates.
  • Tails scavenging.
  • Placer and alluvial gold.

How it works.

The SB concentrator employs an elutriated retention zone at the top of the rotor, requiring the addition of a small volume of process water. The feed stream particles are subjected to gravitational forces of up to 200 G’s (recommended maximum) and are segregated according to effective specific gravity along the smooth spinning rotor wall. The heaviest layers pass over the concentrate bed retained in the riffles at the top of the rotor bowl.

The addition of fluidisation water from behind the riffle beds enable heavy target particles to migrate to the bottom or outside of the bed and be retained in preference to the lighter particles. The high G’s permit effective recovery of even very fine particles (below 10 microns) and the depth of the concentrate bed allows coarser particles in the feed stream to be safely recovered.


Falcon C Series Gravity Concentrator

The Falcon C continuous series, which consumes no additional process water, is used for recovering fine metals and minerals from tailings (flotation or leach), or pre-concentrating of plant feed (either fresh ore or old tailing dumps).

The continuous concentrators have been installed for recovering lead, tin, tantalum, gold, silver, coal, iron ore and their associated minerals.

Significant advantages over competing equipment are lower capital, operating and maintenance costs.


The Continuous Concentrator

Recovering FINE metals and minerals from process streams has always been difficult. With the Falcon ‘C’ series, its design simplicity and 300 G-force, this has made the historically impossible process possible.

Designed never to stop, it continuously produces concentrate yielding weight recoveries as high as 40%. The primary objective of this series is to maximise recovery and reduce weight to subsequent downstream processes. This makes the units perfect for scavenging or pre-concentrating streams, as it uses no elutriation water and produces concentrates that are de-slimed and de-watered (+70% solids by mass).

The Falcon model ‘C’ concentrator is normally utilised where the separation of a relatively small amount of fine heavy material (underflow) from a relatively large amount of lighter gangue is required. With the feed stream particles subjected to gravitational forces of up to 300 G’s, effective recovery of even very fine particles (below 10 microns) is achieved.

One moving part and top-grade component materials such as 316 stainless steel, rubber, polyurethane, tungsten carbide and Ni-hard, mean that you can look forward to greater than 95% operational availability as well as low operating costs.


Falcon UF (Ultra Fine) Series Gravity Concentrator

The Falcon UF Ultrafine series is specifically designed to recover material of 30 microns and finer.

Operating at up to 350G’s, this unit produces an intermittent of concentrate within a range of mass yields of 1% to 25%. No fluidisation water is utilised.

With a maximum particle size of 1mm, the principal application is the recovery of fine free metals, typically Tin, Tantalum, Tungsten, Silver, Gold and PGM’s

The Ultrafine Concentrator

Feed stream particles are subjected to gravitational forces of up to 350 G’s and are segregated according to effective specific gravity along the smooth spinning rotor wall. The high G’s and the lack of fluidising water permit effective recovery of fine particles. The heaviest particles are retained against the rotor wall while the lighter particles migrate over this bed and report to the ‘lights’ launder. The variable lip ring is adjusted to vary the bed thickness and therefore the number of heavies retained during each cycle. The cycle time is adjusted to suit the amount of mass yield required.

When the bed has built up to sufficient grade or mass yield, the feed is stopped, the rotor slowed by braking, and the spray manifolds rinse the heavies out of the rotor underneath the rotor baffle and out of the ‘heavies’ discharge ports.

The variable lip function, the heart of this process, as well as the rotation speed, rinsing and braking and other process variables are all controlled by the Falcon Automation Package ( AutoPAC).

For more information, please contact us here.