XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2957
The RFC technology is licensed to FLSmidth.
Dickinson et al. (2020) describe the results of semi-batch
tests in the laboratory, using the RFC for desliming and
concentration of fine iron ore. Concentrates of about 65%
Fe were obtained in a single flotation stage in the RFC. As
many as five successive batch flotation stages were required
achieve similar Fe grades when using a laboratory-scale
mechanical cell to. Similar grade-recovery curves were pro-
duced using both methods, but significantly higher grades
were obtained by the RFC, with fewer separation stages.
Dabrowski et al. (2024) reported results of a full-scale trial
of an RFC in a copper concentrator.
CONCORDE CELL™
For ultra-fine particles, theory suggests that the rate of flo-
tation is improved by increasing the rate of shear in the
suspension of particles and bubbles. In the Concorde
CellÔ, the pre-aerated feed is raised to supersonic velocities
before passing into a high-shear zone in the flotation cell
(Jameson, 2006).
The Concorde Cell ™ consists of two stages. In the first,
small bubbles are formed in a blast tube under pressure.
The feed enters as a vertical jet, and mixes with air under
pressure. In the second, the aerated mixture then passes
through a choke, where it reaches the speed of sound.
There are three locations in the cell where particle-bubble
contacting can occur: in the plunging jet inside the blast
tube, in the shockwave downstream of the choke, and in
the vortex ring that forms in the impingement bowl. The
local dissipation rate is of the order of 100 kW/m3, one to
two orders of magnitude higher than that in conventional
mechanical cells. The technology is licensed to Metso and
the first commercial application was at the Leinster Nickel
Mine in 2023. Figure 15 shows a schematic and an image
of a Concorde Cell ™.
Test results reported by Metso state that, in a copper
cleaner application, the Concorde Cell ™ increased recovery
by 1.3% and grade by 2% (Dube and Kupka 2023). The
location of this test was not given. It was also noted that
the impingement bowl experienced rapid wear. Table 2 pro-
vides performance data and Figure 12 shows a schematic
and image of the Concorde Cell ™.
coarseAIR™ Cell
The coarseAIR ™ flotation cell, recently developed by the
University of Newcastle in Australia, is also licensed to
FLSmidth. It is a low-turbulence, aerated, fluidized-bed
separator combined with lamellar plates, based on the
REFLUX Classifier ™. A description of the CoarseAIR ™ is
given by Ansoom et al. (2024), and is summarized here.
Figure 15. Concorde Cell™, Schematic and Image (Jameson 2009 and Metso 2024d)
Table 2. Concorde Cell™ Characteristic Data (Metso 2024d)
Typical capacity 85 m3/h
Max slurry density 135 t/m3
Flotation cell capacity up to 3000 m3/h
Typical feed solids percent 10–255
Typical particle size range 10–45 microns
Tailings recycle ratio up to 12%
Typical air to pulp ratio 0.5–1.5
Froth level up to 1 m
The RFC technology is licensed to FLSmidth.
Dickinson et al. (2020) describe the results of semi-batch
tests in the laboratory, using the RFC for desliming and
concentration of fine iron ore. Concentrates of about 65%
Fe were obtained in a single flotation stage in the RFC. As
many as five successive batch flotation stages were required
achieve similar Fe grades when using a laboratory-scale
mechanical cell to. Similar grade-recovery curves were pro-
duced using both methods, but significantly higher grades
were obtained by the RFC, with fewer separation stages.
Dabrowski et al. (2024) reported results of a full-scale trial
of an RFC in a copper concentrator.
CONCORDE CELL™
For ultra-fine particles, theory suggests that the rate of flo-
tation is improved by increasing the rate of shear in the
suspension of particles and bubbles. In the Concorde
CellÔ, the pre-aerated feed is raised to supersonic velocities
before passing into a high-shear zone in the flotation cell
(Jameson, 2006).
The Concorde Cell ™ consists of two stages. In the first,
small bubbles are formed in a blast tube under pressure.
The feed enters as a vertical jet, and mixes with air under
pressure. In the second, the aerated mixture then passes
through a choke, where it reaches the speed of sound.
There are three locations in the cell where particle-bubble
contacting can occur: in the plunging jet inside the blast
tube, in the shockwave downstream of the choke, and in
the vortex ring that forms in the impingement bowl. The
local dissipation rate is of the order of 100 kW/m3, one to
two orders of magnitude higher than that in conventional
mechanical cells. The technology is licensed to Metso and
the first commercial application was at the Leinster Nickel
Mine in 2023. Figure 15 shows a schematic and an image
of a Concorde Cell ™.
Test results reported by Metso state that, in a copper
cleaner application, the Concorde Cell ™ increased recovery
by 1.3% and grade by 2% (Dube and Kupka 2023). The
location of this test was not given. It was also noted that
the impingement bowl experienced rapid wear. Table 2 pro-
vides performance data and Figure 12 shows a schematic
and image of the Concorde Cell ™.
coarseAIR™ Cell
The coarseAIR ™ flotation cell, recently developed by the
University of Newcastle in Australia, is also licensed to
FLSmidth. It is a low-turbulence, aerated, fluidized-bed
separator combined with lamellar plates, based on the
REFLUX Classifier ™. A description of the CoarseAIR ™ is
given by Ansoom et al. (2024), and is summarized here.
Figure 15. Concorde Cell™, Schematic and Image (Jameson 2009 and Metso 2024d)
Table 2. Concorde Cell™ Characteristic Data (Metso 2024d)
Typical capacity 85 m3/h
Max slurry density 135 t/m3
Flotation cell capacity up to 3000 m3/h
Typical feed solids percent 10–255
Typical particle size range 10–45 microns
Tailings recycle ratio up to 12%
Typical air to pulp ratio 0.5–1.5
Froth level up to 1 m