XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2849
that the current SPH simulator does not account for froth
formation or bubble coalescence effects.
CONCLUSIONS
The use of funnels as retrofit designs was proposed to redi-
rect the water flows toward the centre of the flotation tank,
to decrease the entrainment of fine particles. The effect of
two different funnel designs on froth stability and metal-
lurgical performance was assessed. Air recovery experi-
mental measurements in a single-species system showed
that all funnels generate an improvement in froth stability,
however, experiments in a two-species system showed the
opposite effect, highlighting the importance of mineral-
ogy and chemistry on froth stability. Metallurgical results
showed that Funnel 2 resulted in an improvement in grade
and a reduction in entrainment. Funnel 2 consists of a 30°
inclined funnel, with an external diameter equal to the tank
thus leaving no space for particle flow near the walls, and
with a series of holes with a honey-comb mesh pattern for
air, liquid, and particle motion. SPH simulations evidenced
that Funnel 2 may prevent entrainment by reducing the
bubble swarms near the lip. Although further work with
extensive simulation validation and repetitions under dif-
ferent operating conditions is required, this work shows
promising results for the use of retrofit design modifica-
tions to reduce entrainment and enhance fine flotation.
ACKNOWLEDGMENTS
The authors acknowledge funding from the European
Union’s Horizon 2020 research and innovation programme
Fine Future under Grant Agreement No. 821265. The
honeycomb mesh system used in Funnel 2 is based on the
design proposed by Dr Isobel Mackay during her PhD, and
her support is here acknowledged.
REFERENCES
Brito-Parada, P. R., &Cilliers, J. J. (2012). Experimental
and numerical studies of launder configurations in
a two-phase flotation system. Minerals Engineering,
36–38, 119–125. doi: 10.1016/j.mineng.2012.03.009.
Brito-Parada, P. R., Norori-McCormac, A., Morrison, A. J.,
Hadler, K., Cole, K., &Cilliers, J. J. (2017). Flotation
cell hydrodynamics and design modifications investigated
with Positron Emission Particle Tracking. Flotation ’17,
Cape Town, South Africa.
Cilek, E. C. (2009). The effect of hydrodynamic condi-
tions on true flotation and entrainment in flotation
of a complex sulphide ore. International Journal of
Mineral Processing, 90(1–4), 35–44. doi: 10.1016
/j.minpro.2008.10.002.
Cole, K., Mesa, D., van Heerden, M., &Brito-Parada, P. R.
(2023). Effect of Retrofit Design Modifications on the
Macroturbulence of a Three-Phase Flotation Tank—
Flow Characterization Using Positron Emission Particle
Tracking (PEPT). Industrial &Engineering Chemistry
Research. doi: 10.1021/acs.iecr.2c04389.
Gong, J., Peng, Y., Bouajila, A., Ourriban, M., Yeung, A.,
&Liu, Q. (2010). Reducing quartz gangue entrain-
ment in sulphide ore flotation by high molecular
weight polyethylene oxide. International Journal of
Mineral Processing, 97(1–4), 44–51. doi: 10.1016
/j.minpro.2010.07.009.
Jameson, G. J. (2010). New directions in flotation machine
design. Minerals Engineering, 23(11–13), 835–841.
doi: 10.1016/j.mineng.2010.04.001.
Konopacka, Z., &Drzymala, J. (2010). Types of particles
recovery—Water recovery entrainment plots useful in
flotation research. Adsorption, 16(4–5), 313–320. doi:
10.1007/s10450-010-9246-x.
Kracht, W., Orozco, Y., &Acuña, C. (2016). Effect of sur-
factant type on the entrainment factor and selectivity
of flotation at laboratory scale. Minerals Engineering,
92, 216–220. doi: 10.1016/j.mineng.2016.03.028.
Mackay, I. (2019). Investigating flotation at the bench scale—
The effect of design modifications on flotation performance
and the link to particle size [PhD]. Imperial College
London.
Mesa, D., Cole, K., van Heerden, M. R., &Brito-
Parada, P. R. (2021). Hydrodynamic characterisa-
tion of flotation impeller designs using Positron
Emission Particle Tracking (PEPT). Separation and
Purification Technology, 276, 119316. doi: 10.1016
/j.seppur.2021.119316.
Mesa, D., Morrison, A. J., &Brito-Parada, P. R. (2020).
The effect of impeller-stator design on bubble size:
Implications for froth stability and flotation per-
formance. Minerals Engineering, 157, 106533. doi:
10.1016/j.mineng.2020.106533.
Moyo, P., Gomez, C. O., &Finch, J. A. (2007).
Characterizing Frothers using Water Carrying Rate.
Canadian Metallurgical Quarterly, 46(3), 215–220.
doi: 10.1179/cmq.2007.46.3.215.
Neethling, S. J., &Barker, D. J. (2016). Using Smooth
Particle Hydrodynamics (SPH) to model multiphase
mineral processing systems. Minerals Engineering, 90,
17–28. doi: 10.1016/j.mineng.2015.09.022.
that the current SPH simulator does not account for froth
formation or bubble coalescence effects.
CONCLUSIONS
The use of funnels as retrofit designs was proposed to redi-
rect the water flows toward the centre of the flotation tank,
to decrease the entrainment of fine particles. The effect of
two different funnel designs on froth stability and metal-
lurgical performance was assessed. Air recovery experi-
mental measurements in a single-species system showed
that all funnels generate an improvement in froth stability,
however, experiments in a two-species system showed the
opposite effect, highlighting the importance of mineral-
ogy and chemistry on froth stability. Metallurgical results
showed that Funnel 2 resulted in an improvement in grade
and a reduction in entrainment. Funnel 2 consists of a 30°
inclined funnel, with an external diameter equal to the tank
thus leaving no space for particle flow near the walls, and
with a series of holes with a honey-comb mesh pattern for
air, liquid, and particle motion. SPH simulations evidenced
that Funnel 2 may prevent entrainment by reducing the
bubble swarms near the lip. Although further work with
extensive simulation validation and repetitions under dif-
ferent operating conditions is required, this work shows
promising results for the use of retrofit design modifica-
tions to reduce entrainment and enhance fine flotation.
ACKNOWLEDGMENTS
The authors acknowledge funding from the European
Union’s Horizon 2020 research and innovation programme
Fine Future under Grant Agreement No. 821265. The
honeycomb mesh system used in Funnel 2 is based on the
design proposed by Dr Isobel Mackay during her PhD, and
her support is here acknowledged.
REFERENCES
Brito-Parada, P. R., &Cilliers, J. J. (2012). Experimental
and numerical studies of launder configurations in
a two-phase flotation system. Minerals Engineering,
36–38, 119–125. doi: 10.1016/j.mineng.2012.03.009.
Brito-Parada, P. R., Norori-McCormac, A., Morrison, A. J.,
Hadler, K., Cole, K., &Cilliers, J. J. (2017). Flotation
cell hydrodynamics and design modifications investigated
with Positron Emission Particle Tracking. Flotation ’17,
Cape Town, South Africa.
Cilek, E. C. (2009). The effect of hydrodynamic condi-
tions on true flotation and entrainment in flotation
of a complex sulphide ore. International Journal of
Mineral Processing, 90(1–4), 35–44. doi: 10.1016
/j.minpro.2008.10.002.
Cole, K., Mesa, D., van Heerden, M., &Brito-Parada, P. R.
(2023). Effect of Retrofit Design Modifications on the
Macroturbulence of a Three-Phase Flotation Tank—
Flow Characterization Using Positron Emission Particle
Tracking (PEPT). Industrial &Engineering Chemistry
Research. doi: 10.1021/acs.iecr.2c04389.
Gong, J., Peng, Y., Bouajila, A., Ourriban, M., Yeung, A.,
&Liu, Q. (2010). Reducing quartz gangue entrain-
ment in sulphide ore flotation by high molecular
weight polyethylene oxide. International Journal of
Mineral Processing, 97(1–4), 44–51. doi: 10.1016
/j.minpro.2010.07.009.
Jameson, G. J. (2010). New directions in flotation machine
design. Minerals Engineering, 23(11–13), 835–841.
doi: 10.1016/j.mineng.2010.04.001.
Konopacka, Z., &Drzymala, J. (2010). Types of particles
recovery—Water recovery entrainment plots useful in
flotation research. Adsorption, 16(4–5), 313–320. doi:
10.1007/s10450-010-9246-x.
Kracht, W., Orozco, Y., &Acuña, C. (2016). Effect of sur-
factant type on the entrainment factor and selectivity
of flotation at laboratory scale. Minerals Engineering,
92, 216–220. doi: 10.1016/j.mineng.2016.03.028.
Mackay, I. (2019). Investigating flotation at the bench scale—
The effect of design modifications on flotation performance
and the link to particle size [PhD]. Imperial College
London.
Mesa, D., Cole, K., van Heerden, M. R., &Brito-
Parada, P. R. (2021). Hydrodynamic characterisa-
tion of flotation impeller designs using Positron
Emission Particle Tracking (PEPT). Separation and
Purification Technology, 276, 119316. doi: 10.1016
/j.seppur.2021.119316.
Mesa, D., Morrison, A. J., &Brito-Parada, P. R. (2020).
The effect of impeller-stator design on bubble size:
Implications for froth stability and flotation per-
formance. Minerals Engineering, 157, 106533. doi:
10.1016/j.mineng.2020.106533.
Moyo, P., Gomez, C. O., &Finch, J. A. (2007).
Characterizing Frothers using Water Carrying Rate.
Canadian Metallurgical Quarterly, 46(3), 215–220.
doi: 10.1179/cmq.2007.46.3.215.
Neethling, S. J., &Barker, D. J. (2016). Using Smooth
Particle Hydrodynamics (SPH) to model multiphase
mineral processing systems. Minerals Engineering, 90,
17–28. doi: 10.1016/j.mineng.2015.09.022.