XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2837
of 75% and 84%, respectively. For copper, the recovery
split between the froth and screen concentrates was 62%
and 13%, respectively. For molybdenum, the recovery split
was 75% and 9%, respectively. Thus, the screen concen-
trate contributed significantly to the overall recovery and a
classification circuit would be required for this application.
The NovaCell ™ comparison to the Agitair cell is pre-
sented Table 9. The results indicated that the NovaCell ™
achieved a 10% higher copper recovery and 17% higher
molybdenum recovery. These results were similar to the
NovaCell ™ performance in case study 1. However, for the
present case the NovaCell ™ product upgrade ratios were
lower than the Agitair cell.
The NovaCell ™ and Agitair copper results were also
analyzed on a sized basis. The copper recovery-by-size
results for both tests are presented in Figure 8. The plot
indicates that both technologies have similar recoveries in
the –150 µm size fractions, however the NovaCell ™ indi-
cates significantly higher recoveries in the +150 µm size
fractions. Thus, the results suggest that the NovaCell ™
recovered the coarse copper particles more efficiently than
the Agitair cell.
The copper assay-by-size results for both tests are pre-
sented in Figure 9. The plot indicates that the NovaCell ™
copper grades were lower in most of the size fractions.
The lower copper grades in the intermediate and coarse
size fractions were likely due to the NovaCell ™ recovering
more composite copper particles with gangue associations.
The NovaCell ™ product would likely need regrinding and
cleaning to achieve a saleable product grade. Regrinding
of product streams ahead of cleaner circuits is a common
approach adopted for coarse particle flotation (CPF) cir-
cuits. However, care needs to be taken to limit the rougher/
scavenger concentrate mass produced from CPF circuits. If
the CPF circuit is unselective and a large rougher/scavenger
mass is produced, the regrind mill power draw requirements
increase significantly, thus reducing the carbon emission
Table 7. Case study 3 sample characteristics
Particle
Size,
µm
Copper
Feed
Grade, %
Molybdenum
Feed
Grade, ppm
Feed Distributions
Mass Copper Molybdenum
–710 +600 0.27 39 12% 8% 5%
–600 +425 0.33 54 27% 20% 15%
–425 +300 0.40 71 15% 13% 10%
–300 +212 0.45 96 9% 9% 8%
–212 +150 0.54 144 7% 9% 10%
–150 +106 0.59 157 5% 7% 8%
–106 +75 0.71 193 4% 7% 8%
–75 +53 0.81 206 3% 5% 6%
–53 +38 0.89 222 2% 4% 5%
–38 0.54 162 15% 18% 25%
Total 0.45 101 100% 100% 100%
Table 8. Case study 3 summary of flotation conditions
Test Parameter Unit
Test Conditions
NovaCell™ Agitair Cell
System Volume liters 22 5
Test time (min) 40 31
Sample Feed Mass kg 5.3 1.4
Grind Size (P80) µm 550 550
Feed Solids Density (%w/w) 22% 24%
Screen Aperture µm 300 n/a
Diesel g/t 46 52
Collector (PAX) g/t 48 50
Frother (MIBC) ppm (vol) 30 30
pH (Lime) — 9.0 9.1
Eh (NaHS) mV (Ag/AgCl) +12 +8
of 75% and 84%, respectively. For copper, the recovery
split between the froth and screen concentrates was 62%
and 13%, respectively. For molybdenum, the recovery split
was 75% and 9%, respectively. Thus, the screen concen-
trate contributed significantly to the overall recovery and a
classification circuit would be required for this application.
The NovaCell ™ comparison to the Agitair cell is pre-
sented Table 9. The results indicated that the NovaCell ™
achieved a 10% higher copper recovery and 17% higher
molybdenum recovery. These results were similar to the
NovaCell ™ performance in case study 1. However, for the
present case the NovaCell ™ product upgrade ratios were
lower than the Agitair cell.
The NovaCell ™ and Agitair copper results were also
analyzed on a sized basis. The copper recovery-by-size
results for both tests are presented in Figure 8. The plot
indicates that both technologies have similar recoveries in
the –150 µm size fractions, however the NovaCell ™ indi-
cates significantly higher recoveries in the +150 µm size
fractions. Thus, the results suggest that the NovaCell ™
recovered the coarse copper particles more efficiently than
the Agitair cell.
The copper assay-by-size results for both tests are pre-
sented in Figure 9. The plot indicates that the NovaCell ™
copper grades were lower in most of the size fractions.
The lower copper grades in the intermediate and coarse
size fractions were likely due to the NovaCell ™ recovering
more composite copper particles with gangue associations.
The NovaCell ™ product would likely need regrinding and
cleaning to achieve a saleable product grade. Regrinding
of product streams ahead of cleaner circuits is a common
approach adopted for coarse particle flotation (CPF) cir-
cuits. However, care needs to be taken to limit the rougher/
scavenger concentrate mass produced from CPF circuits. If
the CPF circuit is unselective and a large rougher/scavenger
mass is produced, the regrind mill power draw requirements
increase significantly, thus reducing the carbon emission
Table 7. Case study 3 sample characteristics
Particle
Size,
µm
Copper
Feed
Grade, %
Molybdenum
Feed
Grade, ppm
Feed Distributions
Mass Copper Molybdenum
–710 +600 0.27 39 12% 8% 5%
–600 +425 0.33 54 27% 20% 15%
–425 +300 0.40 71 15% 13% 10%
–300 +212 0.45 96 9% 9% 8%
–212 +150 0.54 144 7% 9% 10%
–150 +106 0.59 157 5% 7% 8%
–106 +75 0.71 193 4% 7% 8%
–75 +53 0.81 206 3% 5% 6%
–53 +38 0.89 222 2% 4% 5%
–38 0.54 162 15% 18% 25%
Total 0.45 101 100% 100% 100%
Table 8. Case study 3 summary of flotation conditions
Test Parameter Unit
Test Conditions
NovaCell™ Agitair Cell
System Volume liters 22 5
Test time (min) 40 31
Sample Feed Mass kg 5.3 1.4
Grind Size (P80) µm 550 550
Feed Solids Density (%w/w) 22% 24%
Screen Aperture µm 300 n/a
Diesel g/t 46 52
Collector (PAX) g/t 48 50
Frother (MIBC) ppm (vol) 30 30
pH (Lime) — 9.0 9.1
Eh (NaHS) mV (Ag/AgCl) +12 +8