XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2835
There are multiple examples of froth washing being used
in circuits to reduce gangue entrainment in similar tech-
nologies. The review of Jera and Bhondayi (2022) on froth
washing in flotation showed that froth washing improves
the grade of the concentrate and influences the froth stabil-
ity and mobility.
It should be noted that the higher NovaCell ™ product
copper grades in the +106 µm size fractions, suggest that
the NovaCell ™ selectively recovered coarse copper mineral
particles better than the Agitair cell.
In summary, laboratory results suggest that the proj-
ect objective could be achieved. The NovaCell ™ recovered
74% additional copper from the plant tailings stream.
When compared to conventional flotation technology,
the NovaCell ™ results showed that the recovery improve-
ment was largest in the +212 µm size fractions. Thus, at
the current flotation feed grind size (P80) of ~256 µm, the
NovaCell ™ copper recovery improvement should increase
even further.
Case Study 2—Potential NovaCell™ Impact in Tailings
Scavenging Duty
In case 2, the NovaCell ™ was evaluated in a tailings scav-
enging duty, using the kinetic rate results from laboratory
testwork.
The potential benefits would be the following:
• Increased metal recovery. The test results suggest that
the NovaCell ™ technology can recover floatable cop-
per minerals that are typically lost by conventional
flotation technology (i.e., mechanically agitated
cells).
• Reduced metal minerals to the TSF. Removing more
copper and other sulfides from the tailings stream
reduces the potential risk of acid mine drainage.
Figure 7 presents the proposed circuit configuration
with the NovaCell ™ in the tailings scavenging duty. The
NovaCell ™ feed stream would be the plant rougher tail-
ings. The NovaCell ™ product would be pumped to the
regrind and cleaner circuits to produce a saleable concen-
trate. Note, that the cleaner circuits will likely receive addi-
tional material in this circuit configuration and should be
evaluated to understand whether modifications would be
required. The NovaCell ™ fine tails (i.e., the classification
circuit fines) will feed the TSF, whilst NovaCell ™ coarse
tails could bypass the TSF and be sent for mechanical
dewatering and dry tailings disposal.
At the flotation feed grind size (P80) of ~212 µm, it
is predicted that the plant-scale NovaCell ™ unit, together
with the existing flotation circuit, would increase the final
copper product recovery from 78% to ~85%. This is based
on a copper feed grade of 0.90% Cu.
A high-level economic evaluation was conducted, with
the following assumptions:
• The copper recovery losses in the cleaner circuit were
increased by 1%.
• The plant utilization is 94%
• The copper price is $8,300 USD per tonne
• The plant operating costs are unchanged.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0 100 200 300 400 500 600
Particle Size (μm)
NovaCell Agitair Cell
Figure 6. Case study 2, copper assay-by-size results for the NovaCell and Agitair cell
Copper
Grade
(%)
There are multiple examples of froth washing being used
in circuits to reduce gangue entrainment in similar tech-
nologies. The review of Jera and Bhondayi (2022) on froth
washing in flotation showed that froth washing improves
the grade of the concentrate and influences the froth stabil-
ity and mobility.
It should be noted that the higher NovaCell ™ product
copper grades in the +106 µm size fractions, suggest that
the NovaCell ™ selectively recovered coarse copper mineral
particles better than the Agitair cell.
In summary, laboratory results suggest that the proj-
ect objective could be achieved. The NovaCell ™ recovered
74% additional copper from the plant tailings stream.
When compared to conventional flotation technology,
the NovaCell ™ results showed that the recovery improve-
ment was largest in the +212 µm size fractions. Thus, at
the current flotation feed grind size (P80) of ~256 µm, the
NovaCell ™ copper recovery improvement should increase
even further.
Case Study 2—Potential NovaCell™ Impact in Tailings
Scavenging Duty
In case 2, the NovaCell ™ was evaluated in a tailings scav-
enging duty, using the kinetic rate results from laboratory
testwork.
The potential benefits would be the following:
• Increased metal recovery. The test results suggest that
the NovaCell ™ technology can recover floatable cop-
per minerals that are typically lost by conventional
flotation technology (i.e., mechanically agitated
cells).
• Reduced metal minerals to the TSF. Removing more
copper and other sulfides from the tailings stream
reduces the potential risk of acid mine drainage.
Figure 7 presents the proposed circuit configuration
with the NovaCell ™ in the tailings scavenging duty. The
NovaCell ™ feed stream would be the plant rougher tail-
ings. The NovaCell ™ product would be pumped to the
regrind and cleaner circuits to produce a saleable concen-
trate. Note, that the cleaner circuits will likely receive addi-
tional material in this circuit configuration and should be
evaluated to understand whether modifications would be
required. The NovaCell ™ fine tails (i.e., the classification
circuit fines) will feed the TSF, whilst NovaCell ™ coarse
tails could bypass the TSF and be sent for mechanical
dewatering and dry tailings disposal.
At the flotation feed grind size (P80) of ~212 µm, it
is predicted that the plant-scale NovaCell ™ unit, together
with the existing flotation circuit, would increase the final
copper product recovery from 78% to ~85%. This is based
on a copper feed grade of 0.90% Cu.
A high-level economic evaluation was conducted, with
the following assumptions:
• The copper recovery losses in the cleaner circuit were
increased by 1%.
• The plant utilization is 94%
• The copper price is $8,300 USD per tonne
• The plant operating costs are unchanged.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0 100 200 300 400 500 600
Particle Size (μm)
NovaCell Agitair Cell
Figure 6. Case study 2, copper assay-by-size results for the NovaCell and Agitair cell
Copper
Grade
(%)