784 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
(0.2–1.4%), while molybdenum increases in years 2027
and 2028 (1.7% to 1.9%), but decreases in 2024 and 2025
(–2.0% to –1.5%). These results show the combined effect
of changing makeup water quality and LOM minerals.
CONCLUSIONS
In the first part of the study, the recovery of the five minerals
tested (fast and slow kinetics, and a mixture of all minerals)
decreases when the water had low and high ionic strength
(desalinated and tap water, and seawater, respectively). The
process water and mixtures with 20% and 65% seawater
showed the highest recoveries, which have an intermediate
number of ions. Therefore, the minerals evaluated in this
study need a certain degree of ionic strength (salinity) in
water to reach a suitable recovery.
A synergistic effect was observed for the mixture of fast
and slow minerals, resulting in a higher recovery than that
predicted from the proportions of fast and slow minerals.
Regarding the DDCT, the water quality evolution
along the cycle tests showed a clear trend to reach and equi-
librium in terms of the ionic strength in all testing, which
gives a good estimate of the expected characteristics of the
future water accumulated and recovered in the plant.
In this way, the future process water, obtained from the
recovered water (80%) plus the freshwater makeup (20%),
allowed for developing flotation tests for the future miner-
als. The experimental results showed that the future process
water was less sensitive than the mineral changes, without
significant differences with respect to the water makeup,
with slightly higher ionic strength (1–2 mS/cm higher), for
the period of study (2024 to 2028).
The comparison of mineral recoveries from batch flo-
tation tests, using the initial freshwater makeup and the
process water obtained from DDCT, after water makeup
changes, did not show significant changes. However, the
main differences in the future mineral recoveries relate
to changes in the minerals feed characteristics, including
changes of mineralogy and feed grade. Predictions of metal-
lurgical results for the next years (2024–2028) showed an
incremental recovery of copper (0.2% to 1.4%) for each
new LOM mineral, after dissolution (DDCT) using water
makeup FWM (50/50), while molybdenum increased in
years 2027 and 2028 (1.7% to 1.9%), but decreased in
2024 and 2025 (–2.0% to –1.5%).
ACKNOWLEDGMENTS
The authors are grateful to Agencia Nacional de
Investigación y Desarrollo (ANID), FONDECYT Project
1241830, and Federico Santa María Technical University,
Chile, for providing funding for process modelling and
control research. Additionally, the invaluable contribution
of the concentrator personnel at Compañía Minera Doña
Inés de Collahuasi and its permission to present these
results, are greatly acknowledged.
REFERENCES
Boujounoui, K., Abidi, A., Bacaoui, A., Amari, K.E.,
Yaacoubi, A. (2015). The influence of water quality on
the flotation performance of complex sulphide ores:
Case study at Hajar Mine. Morocco. J. South. Afr. Inst.
Min. Metall. 115, 1243–1251.
Corin, K., Charamba, A., Manono, M. (2024). Water
quality impact on flotation Response: A focus on spe-
cific ions and temperature, Minerals Engineering, 207,
108549.
Table 5. Effect of the future makeup water on the incremental recovery of LOM minerals.
LOM
Mineral Water Type
DDCT Conductivity
(mS/cm)
Incremental Recovery, %.
ΔCu, %ΔFe, %ΔMo, %Δmass, %
2024 Initial: PW Initial 18.5 ± 0.3 0.7 0.4 –2.0 0.2
Makeup: FWM (50/50) Final 12.0 ± 0.5
2025 Initial: FWM (50/50) Initial 10.4 ± 0.1 NA NA NA NA
Makeup: FWM (50/50) Final 12.1 ± 0.2
2026 Initial: FWM (50/50) Initial 10.5 ± 0.2 0.2 –0.2 –1.5 0.3
Makeup: FWM (50/50) Final 11.5 ± 0.6
2027 Initial: FW (50/50) Initial 11.0 ± 0.0 1.1 3.1 1.9 0.1
Makeup: FWM (50/50) Final 11.5 ± 0.5
2028 Initial: FWM (50/50) Initial 8.5 ± 0.3 1.4 –3.8 1.7 0.6
Makeup: FWM (65/35) Final 10.6 ± 0.5
PW: Process water, FWM: Freshwater makeup, NA: Not available.
(0.2–1.4%), while molybdenum increases in years 2027
and 2028 (1.7% to 1.9%), but decreases in 2024 and 2025
(–2.0% to –1.5%). These results show the combined effect
of changing makeup water quality and LOM minerals.
CONCLUSIONS
In the first part of the study, the recovery of the five minerals
tested (fast and slow kinetics, and a mixture of all minerals)
decreases when the water had low and high ionic strength
(desalinated and tap water, and seawater, respectively). The
process water and mixtures with 20% and 65% seawater
showed the highest recoveries, which have an intermediate
number of ions. Therefore, the minerals evaluated in this
study need a certain degree of ionic strength (salinity) in
water to reach a suitable recovery.
A synergistic effect was observed for the mixture of fast
and slow minerals, resulting in a higher recovery than that
predicted from the proportions of fast and slow minerals.
Regarding the DDCT, the water quality evolution
along the cycle tests showed a clear trend to reach and equi-
librium in terms of the ionic strength in all testing, which
gives a good estimate of the expected characteristics of the
future water accumulated and recovered in the plant.
In this way, the future process water, obtained from the
recovered water (80%) plus the freshwater makeup (20%),
allowed for developing flotation tests for the future miner-
als. The experimental results showed that the future process
water was less sensitive than the mineral changes, without
significant differences with respect to the water makeup,
with slightly higher ionic strength (1–2 mS/cm higher), for
the period of study (2024 to 2028).
The comparison of mineral recoveries from batch flo-
tation tests, using the initial freshwater makeup and the
process water obtained from DDCT, after water makeup
changes, did not show significant changes. However, the
main differences in the future mineral recoveries relate
to changes in the minerals feed characteristics, including
changes of mineralogy and feed grade. Predictions of metal-
lurgical results for the next years (2024–2028) showed an
incremental recovery of copper (0.2% to 1.4%) for each
new LOM mineral, after dissolution (DDCT) using water
makeup FWM (50/50), while molybdenum increased in
years 2027 and 2028 (1.7% to 1.9%), but decreased in
2024 and 2025 (–2.0% to –1.5%).
ACKNOWLEDGMENTS
The authors are grateful to Agencia Nacional de
Investigación y Desarrollo (ANID), FONDECYT Project
1241830, and Federico Santa María Technical University,
Chile, for providing funding for process modelling and
control research. Additionally, the invaluable contribution
of the concentrator personnel at Compañía Minera Doña
Inés de Collahuasi and its permission to present these
results, are greatly acknowledged.
REFERENCES
Boujounoui, K., Abidi, A., Bacaoui, A., Amari, K.E.,
Yaacoubi, A. (2015). The influence of water quality on
the flotation performance of complex sulphide ores:
Case study at Hajar Mine. Morocco. J. South. Afr. Inst.
Min. Metall. 115, 1243–1251.
Corin, K., Charamba, A., Manono, M. (2024). Water
quality impact on flotation Response: A focus on spe-
cific ions and temperature, Minerals Engineering, 207,
108549.
Table 5. Effect of the future makeup water on the incremental recovery of LOM minerals.
LOM
Mineral Water Type
DDCT Conductivity
(mS/cm)
Incremental Recovery, %.
ΔCu, %ΔFe, %ΔMo, %Δmass, %
2024 Initial: PW Initial 18.5 ± 0.3 0.7 0.4 –2.0 0.2
Makeup: FWM (50/50) Final 12.0 ± 0.5
2025 Initial: FWM (50/50) Initial 10.4 ± 0.1 NA NA NA NA
Makeup: FWM (50/50) Final 12.1 ± 0.2
2026 Initial: FWM (50/50) Initial 10.5 ± 0.2 0.2 –0.2 –1.5 0.3
Makeup: FWM (50/50) Final 11.5 ± 0.6
2027 Initial: FW (50/50) Initial 11.0 ± 0.0 1.1 3.1 1.9 0.1
Makeup: FWM (50/50) Final 11.5 ± 0.5
2028 Initial: FWM (50/50) Initial 8.5 ± 0.3 1.4 –3.8 1.7 0.6
Makeup: FWM (65/35) Final 10.6 ± 0.5
PW: Process water, FWM: Freshwater makeup, NA: Not available.