10
SIGNIFICANCE TO FLOTATION
Cappuccitti and Nesset described the significant progress
over the past few years on characterizing and understanding
the hydrodynamic properties of frothers and collectors and
their effect on flotation performance [25]. This relationship
between chemistry and hydrodynamics has dramatic impli-
cations for how flotation circuits should be controlled and
optimized. Previous work showed that choosing a frother of
the right ‘strength’ is critical to the optimization process and
that collector chemistry influences hydrodynamic proper-
ties and needs to be considered. Collectors, like frothers,
are surface-active agents and are likely to exhibit hydro-
dynamic characteristics. It is not desirable that collectors
have strong frothing characteristics. Weaker frothers may
be needed so that the froth is not excessively stabilized if it
is already strongly affected by solids or other considerations
such as high salt content. To achieve the desired outcome,
the overall system of reagents and operating parameters
must be considered. Frothers clearly have the potential to
be one of the most useful variables for exploitation in a
flotation circuit. The data shown in this case study on a
Merensky ore is consistent with the findings of Cappuccitti
and Nesset [25].
To further expand on this study the same methodol-
ogy for screening frothers as described for the Merensky ore
case study was applied on a PGM-bearing, high chromite
UG2 ore. The baseline was Senfroth 200 and the frothers
screened were Senfroth 150, Senfroth 522 and a newly for-
mulated frother, Genfroth 200.
Figures 10A and 10B, Figures 11A and 11B and Table 2
show the metallurgical data obtained during a UG2 ore hot
float screening of the above-mentioned frothers in combi-
nation with other reagents.
Senfroth 150 and Genfroth 200 were specifically
designed for PGM ores with the aim of improving the
overall PGM concentrate grade and recovery. They should
be particularly advantageous for the processing of UG2
ore types where chromite deportment to the concentrate
by entrainment attracts penalties during downstream
processing. However, Genfroth 200 was also designed to
be a more cost-effective frother for PGM ores due to the
Figure 9. Mass pull from bench-scale metallurgical tests versus froth stability
Table 2. Metallurgical data obtained screening of frothers
with reagents during a UG2 ore hot float on a rougher feed.
Mass
(%)
4E PGM
Recovery
(%)
4E PGM
Grade
(fl/t)
Cr
2 O
3 Grade
(%)
Senfroth 200 7.3 79 46.9 9.3
Senfroth 150 7.9 82 45.6 9.0
Genfroth 200 7.7 82 47.0 9.2
Senfroth 522 7.6 81 45.1 10.1
SIGNIFICANCE TO FLOTATION
Cappuccitti and Nesset described the significant progress
over the past few years on characterizing and understanding
the hydrodynamic properties of frothers and collectors and
their effect on flotation performance [25]. This relationship
between chemistry and hydrodynamics has dramatic impli-
cations for how flotation circuits should be controlled and
optimized. Previous work showed that choosing a frother of
the right ‘strength’ is critical to the optimization process and
that collector chemistry influences hydrodynamic proper-
ties and needs to be considered. Collectors, like frothers,
are surface-active agents and are likely to exhibit hydro-
dynamic characteristics. It is not desirable that collectors
have strong frothing characteristics. Weaker frothers may
be needed so that the froth is not excessively stabilized if it
is already strongly affected by solids or other considerations
such as high salt content. To achieve the desired outcome,
the overall system of reagents and operating parameters
must be considered. Frothers clearly have the potential to
be one of the most useful variables for exploitation in a
flotation circuit. The data shown in this case study on a
Merensky ore is consistent with the findings of Cappuccitti
and Nesset [25].
To further expand on this study the same methodol-
ogy for screening frothers as described for the Merensky ore
case study was applied on a PGM-bearing, high chromite
UG2 ore. The baseline was Senfroth 200 and the frothers
screened were Senfroth 150, Senfroth 522 and a newly for-
mulated frother, Genfroth 200.
Figures 10A and 10B, Figures 11A and 11B and Table 2
show the metallurgical data obtained during a UG2 ore hot
float screening of the above-mentioned frothers in combi-
nation with other reagents.
Senfroth 150 and Genfroth 200 were specifically
designed for PGM ores with the aim of improving the
overall PGM concentrate grade and recovery. They should
be particularly advantageous for the processing of UG2
ore types where chromite deportment to the concentrate
by entrainment attracts penalties during downstream
processing. However, Genfroth 200 was also designed to
be a more cost-effective frother for PGM ores due to the
Figure 9. Mass pull from bench-scale metallurgical tests versus froth stability
Table 2. Metallurgical data obtained screening of frothers
with reagents during a UG2 ore hot float on a rougher feed.
Mass
(%)
4E PGM
Recovery
(%)
4E PGM
Grade
(fl/t)
Cr
2 O
3 Grade
(%)
Senfroth 200 7.3 79 46.9 9.3
Senfroth 150 7.9 82 45.6 9.0
Genfroth 200 7.7 82 47.0 9.2
Senfroth 522 7.6 81 45.1 10.1