XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2789
higher measured mass of the fully coated bubble in the
bimodal system compared to the monomodal system, sug-
gesting that the 176 µm GBs are indeed attached, but in
smaller numbers.
Effect of Ultrafine Particles on the Attachment Rate
and Packing Density of Fine Particles
Ultrafine particles can strongly interact with frothers and
collectors and thus influence their interfacial behavior
(Eftekhari et al. 2020 Eftekhari et al. 2024). They can also
change the dynamics of particle attachment by adsorb-
ing on the surface of bubbles or particles. Adsorption of
ultrafine particles on the bubble surface could hinder GB
attachment by creating steric hindrance or over-stabi-
lizing the liquid film, which delays the rupture and thus
the attachment process. On the other hand, adsorption of
ultrafine particles on the surface of coarser particles can
reduce the amount of film drainage required to rupture
the intervening film, thereby increasing the likelihood of
rupture and thus attachment. The addition of ultrafine par-
ticles to the system can also significantly alter the pH and
ionic strength of the system, which in turn can influence
the dynamics of coarser particle attachment. For instance,
flotation can be hindered at low pH if a cationic collector
is used as the hydrogen ions must compete with the col-
lector for adsorption sites on the particle surface, and vice
Figure 3. Size distribution for 66 µm GBs (a) before collection and (b) after collection. Size distribution for mixed GBs of 40
wt.% 66 µm and 60 wt.% 176 µm (c) before collection and (d) after collection. The mean diameter is shown in the upper left
of each subfigure
higher measured mass of the fully coated bubble in the
bimodal system compared to the monomodal system, sug-
gesting that the 176 µm GBs are indeed attached, but in
smaller numbers.
Effect of Ultrafine Particles on the Attachment Rate
and Packing Density of Fine Particles
Ultrafine particles can strongly interact with frothers and
collectors and thus influence their interfacial behavior
(Eftekhari et al. 2020 Eftekhari et al. 2024). They can also
change the dynamics of particle attachment by adsorb-
ing on the surface of bubbles or particles. Adsorption of
ultrafine particles on the bubble surface could hinder GB
attachment by creating steric hindrance or over-stabi-
lizing the liquid film, which delays the rupture and thus
the attachment process. On the other hand, adsorption of
ultrafine particles on the surface of coarser particles can
reduce the amount of film drainage required to rupture
the intervening film, thereby increasing the likelihood of
rupture and thus attachment. The addition of ultrafine par-
ticles to the system can also significantly alter the pH and
ionic strength of the system, which in turn can influence
the dynamics of coarser particle attachment. For instance,
flotation can be hindered at low pH if a cationic collector
is used as the hydrogen ions must compete with the col-
lector for adsorption sites on the particle surface, and vice
Figure 3. Size distribution for 66 µm GBs (a) before collection and (b) after collection. Size distribution for mixed GBs of 40
wt.% 66 µm and 60 wt.% 176 µm (c) before collection and (d) after collection. The mean diameter is shown in the upper left
of each subfigure