XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 729
strength. As the frother dosage was increased whilst the
other reagents were kept constant, both the water and sol-
ids recoveries increased. This was the case for both low and
high process water ionic strength conditions. The effect of
the collector was hardly significant for all the tested condi-
tions except for two cases. Contrary to its intended func-
tion, an increase in collector dosage as seen from LLLL to
HLLL yielded low solids and water recoveries, this was in
the absence of depressant dosages. On the second case, a
slight increase is seen when a depressant dosage is intro-
duced, and that is on LHLL to HHLL.
Sedimentation of Concentrate Slurries from the Batch
Flotation Process
A summary of the settling rates for all the tests is presented
in Figure 2. Settling rates are seen to increase from LLLL to
HHHH for both the control and coagulant. The opposite
was observed for all the conditions introducing a flocculant,
with settling rates decreasing from a region of low ionic
strength to high ionic strength. Overall, the highest settling
rate was seen on LHLL, in the presence of a flocculant, at
79 mg/L. The CMC was significantly dominant compared
to the other reagents at low ionic strength. Less variations
were observed in the high ionic strength region regarding
settling rates. This then shows that high ionic strength was
influential in driving the settling rates in its presence.
CONCLUSIONS
Flotation conditions consisting of a depressant had the
highest sedimentation, particularly when the concentrates
were subjected to a flocculant. Combinations of a flocculant
and coagulant proved less effective in concentrate sedimen-
tation compared to sedimentation with just a coagulant,
however these still had better sedimentation compared to
the controlled and with a coagulant only sedimentation
experiment.
REFERENCES
Becker, M, Harris, P J, Wiese, J G, Bradshaw, D.J., 2009.
Mineralogical characterisation of naturally floatable
gangue in Merensky reef ore flotation. Int J Miner
Process 246–255.
Bradshaw, D.J., Oostendorp, B., Harris, P.J., 2005.
Development of methodologies to improve the assess-
ment of reagent behaviour in flotation with particular
reference to collectors and depressants. Miner Eng 18,
239–246. doi: 10.1016/j.mineng.2004.09.012.
Figure 1. Cumulative water and solids recoveries for all tested conditions. Error bars indicate the standard deviation on the
duplicate experiments
strength. As the frother dosage was increased whilst the
other reagents were kept constant, both the water and sol-
ids recoveries increased. This was the case for both low and
high process water ionic strength conditions. The effect of
the collector was hardly significant for all the tested condi-
tions except for two cases. Contrary to its intended func-
tion, an increase in collector dosage as seen from LLLL to
HLLL yielded low solids and water recoveries, this was in
the absence of depressant dosages. On the second case, a
slight increase is seen when a depressant dosage is intro-
duced, and that is on LHLL to HHLL.
Sedimentation of Concentrate Slurries from the Batch
Flotation Process
A summary of the settling rates for all the tests is presented
in Figure 2. Settling rates are seen to increase from LLLL to
HHHH for both the control and coagulant. The opposite
was observed for all the conditions introducing a flocculant,
with settling rates decreasing from a region of low ionic
strength to high ionic strength. Overall, the highest settling
rate was seen on LHLL, in the presence of a flocculant, at
79 mg/L. The CMC was significantly dominant compared
to the other reagents at low ionic strength. Less variations
were observed in the high ionic strength region regarding
settling rates. This then shows that high ionic strength was
influential in driving the settling rates in its presence.
CONCLUSIONS
Flotation conditions consisting of a depressant had the
highest sedimentation, particularly when the concentrates
were subjected to a flocculant. Combinations of a flocculant
and coagulant proved less effective in concentrate sedimen-
tation compared to sedimentation with just a coagulant,
however these still had better sedimentation compared to
the controlled and with a coagulant only sedimentation
experiment.
REFERENCES
Becker, M, Harris, P J, Wiese, J G, Bradshaw, D.J., 2009.
Mineralogical characterisation of naturally floatable
gangue in Merensky reef ore flotation. Int J Miner
Process 246–255.
Bradshaw, D.J., Oostendorp, B., Harris, P.J., 2005.
Development of methodologies to improve the assess-
ment of reagent behaviour in flotation with particular
reference to collectors and depressants. Miner Eng 18,
239–246. doi: 10.1016/j.mineng.2004.09.012.
Figure 1. Cumulative water and solids recoveries for all tested conditions. Error bars indicate the standard deviation on the
duplicate experiments