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Woodgrove flotation reactors a revolution in flotation? (5 replies)

4 months ago
vsrangarajan 4 months ago

Are the Woodgrove flotation reactors the new revolution in flotation? Any comparison of these machines with existing ones?

4 months ago
David 4 months ago
1 like by johnclark

Hi and welcome,

The Woodgrove flotation reactors is very successful in certain applications.  You always need to test your ore to confirm.

According to Woodgrove, the Staged Flotation Reactor (SFR) was developed by going back to the first principles of flotation and examining how best to optimize the different stages of flotation without preconceived limitations. The result is a machine which optimizes the three stages of flotation into three separate zones, so that each zone is mutually exclusive of the requirements of other zones. The back drop of the foam is minimal and tightly controlled. Recovery zone "tight" pulp allows much more control in a scanning SFR, resulting in better recovery and upgrade.

Woodgrove claims its SFR to have for benefits:

  • Reduced energy consumption by approximately 50%
  • The space required is only 60% to 50% of conventional mechanical cells used.
  • Air consumption is reduced by approximately 80%
  • Smaller units required to achieve equivalent results
  • Reduced building height up to 3m in large plants
  • Better control circuit
  • minor instrumentation
  • Less wear and maintenance costs due to the lower tip speed of the impeller
  • Advanced automation control is simpler, faster and less cost and maintenance and installation


For more about Woodgrove' SFR you may want to watch:


And for best full details: Glenn Dobby & Glenn Kosick from http://woodgrovetech.com/

See https://www.911metallurgist.com/blog/woodgrove-sfr-staged-flotation-reactor

Jorge Ganoza
4 months ago
Jorge Ganoza 4 months ago
1 like by David

Woodgrove Technologies developed the flotation cell called Staged Flotation Reactor (SFR). David mentioned the main features of the SFR cells. There are other similar flotation cells, but they have some operating and technical problems (e.g. sanding, circulating load is not handled properly, the residence time, etc).

I believe that Woodgrove design is more friendly and robust. Also, there is a very important point to keep in mind, the designers have a lot of experience in flotation, specially in the design of column cells. Some time ago, they established Minnovex, probably the main manufacturer of flotations columns. 

If it is possible to design a flotation circuit equipped with SFR flotation cells. It is a real advantage.

Greg Henderson
2 months ago
Greg Henderson 2 months ago

I have been involved in two projects now that have adopted SFRs, one for gold recovery accompanying a low sulphide content and the other for pyrite recovery from a copper cleaner circuit.  The latter is operating and apparently working well after some hydraulic modifications and the former has yet to be installed.  Bang for buck they are more expensive than tank cells and are probably best suited to smaller plants (<1 Mt/a).  They do however draw less power and have a smaller footprint.  It should be noted though that they need a greater step height between cells than an equivalent tank cell train which is an important consideration for a float plant in a building but no real issue for an outdoors plant.  Overall I think they could be a winner but its hard to get operating data.  They don't have a patent which is why they are understandably close lipped about their products but there are some smart guys behind the technology.  Ore can be piloted at their facility in Canada but there isn't really any small bench scale equivalent (1 or 2 kg) test that can be employed, they need around 80 kg as a minimum.  As a cleaner stage they have a lot of appeal as they can achieve remarkable upgrade ratios which means reducing the number of flotation stages.  Worth a look for your projects, especially for fine particle scenarios.

2 months ago
David 2 months ago

Thanks for this Greg.  

SFR cost > mechanical cells but and likely also > than columns?

Am not sure they want a Patent or if they can obtain a Patent. 

I think the Hoover type of 1916 and the Woodgrove Technology of 2016 are … “similar” in working principle.

Woodgrove Technologies


Greg Henderson
2 months ago
Greg Henderson 2 months ago
1 like by Charlie

Ha!  I like that, the Hoover cell!  We'll be digging out De Re Metallica next, another classic. 

Yes, I believe it is a case of prior art which is why they guard their technology closely, fair enough.  They claim that most of the energy in a tank cell, especially large ones, is spent on suspending particles rather than inducing collision, the latter being the forte of the SFR.  This make sense when you look at the kW/m3 which falls away with larger cells so less energy must be going into particle attachment.  Most of their blue chips are investing in SFRs so they must be taking them seriously.  Spence mine in Chile tried them out but I never saw the results.  Its worth talking to them to learn more about what they are up to. 

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