XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2821
For the repeat tests, the Cu recovery was 24.7% ± 2.5%,
and the Si recovery was 0.30% ± 0.06%, both at the 95%
confidence level. The variability between these tests was rel-
atively small, indicating repeatable results were achievable
when conducting tests over a relatively short time interval
under the same operating conditions. In comparison, for
the center point runs, the Cu recovery was 28.3% ± 5.9%,
and the Si recovery was 2.99% ± 2.45%, again at the 95%
confidence level. A larger variation was observed between
these results, likely due to changes in feed characteristics
over the time period during which the screening tests were
performed. The data set, however, showed sufficient con-
sistency for analysis, with the randomized block design
enabling the removal of the effect of these changes during
the regression analysis.
Overview of Jameson Cell Performance in Scavenging
The elemental (Cu and Si), mass flow, and solids concentra-
tion data were mass balanced for all tests using the Solver
Add-in in Excel to minimize the sum of squares error asso-
ciated with the system. A good fit between the mass bal-
anced and experimental data was obtained for all tests.
The feed grade to the pilot rig during the screening
tests was 0.081% ± 0.005% Cu and 29.0% ± 1.0% Si, both
at the 95% confidence level. The Cu feed grade is low, with
a substantial proportion of gangue in the feed, as expected
for scavenging duties.
The Cu grade-recovery performance achieved in the
screening tests is shown in Figure 5.
A wide range of performance was observed as the
operating conditions of the Jameson cell were adjusted. As
expected, there is a trade-off between recovery and grade
generally, the concentrate grade decreases as recovery
increases. The conditions where reasonably good copper
recoveries were achieved (30%) required operating with:
Feed solids concentrations less than 25%
Lower vacuum pressure (–5 kPa to –10 kPa), i.e.,
higher air flow rate
No or little wash water addition at shallow froth
depths (50 mm to 75 mm)
Frother addition at dosages between 30 ppm and
50 ppm
It is worth noting that the copper recoveries achieved in
the screening tests were satisfactory, considering that the
roughing stage copper recovery was over 90% before divert-
ing feed to the pilot rig.
Figure 6 shows the selectivity between copper and silica
during the screening tests. The diagonal line equates to no
selectivity between Cu and Si during flotation. The further
the results fall to the right of this line, the greater the selec-
tivity. At all operating conditions, a high degree of selectiv-
ity was achieved between the gangue (Si) and Cu recovered
to the concentrate.
The results show that the Jameson cell could achieve
acceptable performance in this scavenging duty, with a high
degree of selectivity between the scavenger feed’s valuable
Cu and non-valuable Si elements.
0
3
6
9
12
15
18
21
0 10 20 30 40 50 60 70
Cu Recovery (%)
Figure 5. Copper grade-recovery performance of the Jameson cell in scavenging during the
screening tests
Cu
Concentrate
Grade
(%)
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Extracted Text (may have errors)

XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2821
For the repeat tests, the Cu recovery was 24.7% ± 2.5%,
and the Si recovery was 0.30% ± 0.06%, both at the 95%
confidence level. The variability between these tests was rel-
atively small, indicating repeatable results were achievable
when conducting tests over a relatively short time interval
under the same operating conditions. In comparison, for
the center point runs, the Cu recovery was 28.3% ± 5.9%,
and the Si recovery was 2.99% ± 2.45%, again at the 95%
confidence level. A larger variation was observed between
these results, likely due to changes in feed characteristics
over the time period during which the screening tests were
performed. The data set, however, showed sufficient con-
sistency for analysis, with the randomized block design
enabling the removal of the effect of these changes during
the regression analysis.
Overview of Jameson Cell Performance in Scavenging
The elemental (Cu and Si), mass flow, and solids concentra-
tion data were mass balanced for all tests using the Solver
Add-in in Excel to minimize the sum of squares error asso-
ciated with the system. A good fit between the mass bal-
anced and experimental data was obtained for all tests.
The feed grade to the pilot rig during the screening
tests was 0.081% ± 0.005% Cu and 29.0% ± 1.0% Si, both
at the 95% confidence level. The Cu feed grade is low, with
a substantial proportion of gangue in the feed, as expected
for scavenging duties.
The Cu grade-recovery performance achieved in the
screening tests is shown in Figure 5.
A wide range of performance was observed as the
operating conditions of the Jameson cell were adjusted. As
expected, there is a trade-off between recovery and grade
generally, the concentrate grade decreases as recovery
increases. The conditions where reasonably good copper
recoveries were achieved (30%) required operating with:
Feed solids concentrations less than 25%
Lower vacuum pressure (–5 kPa to –10 kPa), i.e.,
higher air flow rate
No or little wash water addition at shallow froth
depths (50 mm to 75 mm)
Frother addition at dosages between 30 ppm and
50 ppm
It is worth noting that the copper recoveries achieved in
the screening tests were satisfactory, considering that the
roughing stage copper recovery was over 90% before divert-
ing feed to the pilot rig.
Figure 6 shows the selectivity between copper and silica
during the screening tests. The diagonal line equates to no
selectivity between Cu and Si during flotation. The further
the results fall to the right of this line, the greater the selec-
tivity. At all operating conditions, a high degree of selectiv-
ity was achieved between the gangue (Si) and Cu recovered
to the concentrate.
The results show that the Jameson cell could achieve
acceptable performance in this scavenging duty, with a high
degree of selectivity between the scavenger feed’s valuable
Cu and non-valuable Si elements.
0
3
6
9
12
15
18
21
0 10 20 30 40 50 60 70
Cu Recovery (%)
Figure 5. Copper grade-recovery performance of the Jameson cell in scavenging during the
screening tests
Cu
Concentrate
Grade
(%)

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