2792 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
DISCUSSION ON APPLICABILITY IN
FLOTATION PROCESSES
Figure 8 shows the ratio of the number of attached GBs to
a single bubble in the NPs system to the water system, as a
function time. The values are calculated from slightly modi-
fied version of Equation 1 with KNPs=40, Kw=4, ΘNPs =0.5,
and Θw =0.8. The modification is needed to translate the
surface coverage values to number values, NπR A
p
2 H =.
As can be seen, the number of attached GBs in the
NPs system is initially greater than that in the water sys-
tem. After some time, however, this changes and the num-
ber of GBs in the water system exceeds the number of
GBs in the NP system. It can be concluded that whether
NPs can increase the final recovery in the flotation cell by
these specific mechanisms, i.e., increasing the attachment
probability and decreasing the packing density, depends on
the residence time of the bubble in the flotation cell.
Based on the reported results, it seems that NPs can
increase the attachment probability and thus attachment
rate of the GBs. However, it is not clear if this effect is
caused by the NPs attachment to the GBs as reported by
Yang et al. (Yang et al. 2011), or the change in pH and
ionic strength due to the co-ions of added NPs and surfac-
tants. Moreover, the possibility of surfactant rearrangement
between NPs and GBs cannot be excluded, which means
that GBs can be made more hydrophobic by the surfac-
tant molecules transferred from the surface of the NPs to
the surface of the GBs. Therefore, further experiments such
as SEM, zeta potential and contact angle measurements
are required to properly evaluate the effect of NPs on the
dynamics of particle attachment.
Figure 7. Snapshots to illustrate the packing density of GBs (3gr of 66 µm GBs, conditioned with 0.006
CMC CTAB, and stirred at 400 rpm) on bubble surface for NPSCs (2.0 wt.% NP9 +0.3 CMC CTAB)
that is compressed to from 2.5 mm to 1.5 mm in diameter, following a 1000 s waiting time
Figure 8. N /N
NPSCs
GBs
w
GBs as a function of time. The curves are calculated from Eq. 1 with
K
NPSCs =40, K
w =4, and Θ
NPSCs =0.5, and Θ
w =0.8
DISCUSSION ON APPLICABILITY IN
FLOTATION PROCESSES
Figure 8 shows the ratio of the number of attached GBs to
a single bubble in the NPs system to the water system, as a
function time. The values are calculated from slightly modi-
fied version of Equation 1 with KNPs=40, Kw=4, ΘNPs =0.5,
and Θw =0.8. The modification is needed to translate the
surface coverage values to number values, NπR A
p
2 H =.
As can be seen, the number of attached GBs in the
NPs system is initially greater than that in the water sys-
tem. After some time, however, this changes and the num-
ber of GBs in the water system exceeds the number of
GBs in the NP system. It can be concluded that whether
NPs can increase the final recovery in the flotation cell by
these specific mechanisms, i.e., increasing the attachment
probability and decreasing the packing density, depends on
the residence time of the bubble in the flotation cell.
Based on the reported results, it seems that NPs can
increase the attachment probability and thus attachment
rate of the GBs. However, it is not clear if this effect is
caused by the NPs attachment to the GBs as reported by
Yang et al. (Yang et al. 2011), or the change in pH and
ionic strength due to the co-ions of added NPs and surfac-
tants. Moreover, the possibility of surfactant rearrangement
between NPs and GBs cannot be excluded, which means
that GBs can be made more hydrophobic by the surfac-
tant molecules transferred from the surface of the NPs to
the surface of the GBs. Therefore, further experiments such
as SEM, zeta potential and contact angle measurements
are required to properly evaluate the effect of NPs on the
dynamics of particle attachment.
Figure 7. Snapshots to illustrate the packing density of GBs (3gr of 66 µm GBs, conditioned with 0.006
CMC CTAB, and stirred at 400 rpm) on bubble surface for NPSCs (2.0 wt.% NP9 +0.3 CMC CTAB)
that is compressed to from 2.5 mm to 1.5 mm in diameter, following a 1000 s waiting time
Figure 8. N /N
NPSCs
GBs
w
GBs as a function of time. The curves are calculated from Eq. 1 with
K
NPSCs =40, K
w =4, and Θ
NPSCs =0.5, and Θ
w =0.8