1
24-032
Enhancement of Ultrafine Phosphate Flotation Using Eriez’
Cavtube Column Flotation Technology
Maoming Fan
Eriez Flotation, Erie, PA, USA
Sunil Kumar
Industries Chimiques du Senegal (ICS),
Dakar, Senegal
Rahul Singh
Eriez Flotation, Erie, PA, USA
Erich Dohm
Eriez Flotation, Erie, PA, USA
ABSTRACT
The rapid increase of P2O5 use for food, biofuels, and
LiFePO4 batteries etc. accelerates the depletion rate of
phosphate reserves. In the phosphate industry, a significant
amount of ultrafine phosphate has been discarded as slime
tailing due to processing difficulties. The major problems
associated with ultrafine particle flotation are low prob-
ability of bubble-particle collision and adhesion, and high
probability of unwanted gangue particles entrainment. This
paper investigates the enhanced ultrafine phosphate parti-
cle flotation probability by Eriez’ CavTube generated fine/
ultrafine bubbles and the improved flotation selectivity by
wash water etc. Ultrafine phosphates with various gangue
minerals of quartz/muscovite, calcite/dolomite, and iron/
silica were studied. Microscopic observations show that the
entrained ultrafine gangue minerals can be minimized by
using wash water in column flotation. A three-factor three-
level central composite experimental design was conducted
for ultrafine phosphate flotation. For comparison, both
benchtop mechanical cell and laboratory column flotation
tests were performed at their optimal respective flotation
conditions. Using Eriez CavTube column flotation tech-
nology for Industries Chimiques du Senegal (ICS) ultra-
fine slime tailings, a concentrate grade of 36.0% P2O5,
was achieved at 89.4% P2O5 recovery. Improved flotation
performance was achieved using column flotation as com-
pared to benchtop mechanical cell flotation. The benefits of
Eriez’ column flotation technology realized from this study
include the high P2O5 grade and recovery.
INTRODUCTION
Phosphate is crucial for plants and animals, including
humans. Isaac Asimov, an important science writer, defined
phosphorus as “life’s bottleneck.” The rapid increase in
P2O5 use is mainly caused by the growth in demand for
food because, coupled with increased food crops for bio-
fuels and the great demand for LiFePO4 batteries, etc. In
many phosphate mines, a significant amount of phosphate
is routinely discarded as an ultrafine slime tailing stream
due to technical and economic barriers using conventional
flotation technology. Ultrafine particle flotation has been
a long-standing problem, especially for non-sulfide ores
flotation. The major issues associated with ultrafine par-
ticle flotation are the low probability of bubble-particle
collision, the low probability of bubble-particle adhesion,
and the high probability of unwanted gangue particles
entrainment.
In the past twenty years, scholars have conducted
extensive scientific work to improve fine/ultrafine particle
flotation using fine and ultrafine bubbles generated by
hydrodynamic cavitation [1–20]. Ultrafine bubbles can
bridge hydrophobic particles to form aggregates [21–23]
and increase the ultrafine particles flotation selectivity and
flotation kinetics. Cavitation tube generated nanobubbles
can not only promote the formation of flocs, but also
increase the stability of flocs [24–28]. Improved flotation
performance by cavitation tube generated fine bubbles has
been verified in the flotation of various minerals such as
quartz [29–33], sulfide [34–41], phosphate [42–46], coal
24-032
Enhancement of Ultrafine Phosphate Flotation Using Eriez’
Cavtube Column Flotation Technology
Maoming Fan
Eriez Flotation, Erie, PA, USA
Sunil Kumar
Industries Chimiques du Senegal (ICS),
Dakar, Senegal
Rahul Singh
Eriez Flotation, Erie, PA, USA
Erich Dohm
Eriez Flotation, Erie, PA, USA
ABSTRACT
The rapid increase of P2O5 use for food, biofuels, and
LiFePO4 batteries etc. accelerates the depletion rate of
phosphate reserves. In the phosphate industry, a significant
amount of ultrafine phosphate has been discarded as slime
tailing due to processing difficulties. The major problems
associated with ultrafine particle flotation are low prob-
ability of bubble-particle collision and adhesion, and high
probability of unwanted gangue particles entrainment. This
paper investigates the enhanced ultrafine phosphate parti-
cle flotation probability by Eriez’ CavTube generated fine/
ultrafine bubbles and the improved flotation selectivity by
wash water etc. Ultrafine phosphates with various gangue
minerals of quartz/muscovite, calcite/dolomite, and iron/
silica were studied. Microscopic observations show that the
entrained ultrafine gangue minerals can be minimized by
using wash water in column flotation. A three-factor three-
level central composite experimental design was conducted
for ultrafine phosphate flotation. For comparison, both
benchtop mechanical cell and laboratory column flotation
tests were performed at their optimal respective flotation
conditions. Using Eriez CavTube column flotation tech-
nology for Industries Chimiques du Senegal (ICS) ultra-
fine slime tailings, a concentrate grade of 36.0% P2O5,
was achieved at 89.4% P2O5 recovery. Improved flotation
performance was achieved using column flotation as com-
pared to benchtop mechanical cell flotation. The benefits of
Eriez’ column flotation technology realized from this study
include the high P2O5 grade and recovery.
INTRODUCTION
Phosphate is crucial for plants and animals, including
humans. Isaac Asimov, an important science writer, defined
phosphorus as “life’s bottleneck.” The rapid increase in
P2O5 use is mainly caused by the growth in demand for
food because, coupled with increased food crops for bio-
fuels and the great demand for LiFePO4 batteries, etc. In
many phosphate mines, a significant amount of phosphate
is routinely discarded as an ultrafine slime tailing stream
due to technical and economic barriers using conventional
flotation technology. Ultrafine particle flotation has been
a long-standing problem, especially for non-sulfide ores
flotation. The major issues associated with ultrafine par-
ticle flotation are the low probability of bubble-particle
collision, the low probability of bubble-particle adhesion,
and the high probability of unwanted gangue particles
entrainment.
In the past twenty years, scholars have conducted
extensive scientific work to improve fine/ultrafine particle
flotation using fine and ultrafine bubbles generated by
hydrodynamic cavitation [1–20]. Ultrafine bubbles can
bridge hydrophobic particles to form aggregates [21–23]
and increase the ultrafine particles flotation selectivity and
flotation kinetics. Cavitation tube generated nanobubbles
can not only promote the formation of flocs, but also
increase the stability of flocs [24–28]. Improved flotation
performance by cavitation tube generated fine bubbles has
been verified in the flotation of various minerals such as
quartz [29–33], sulfide [34–41], phosphate [42–46], coal