3522 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
to prepare the feed for the subsequent sulphide flotation
experiments.
Building upon the Design of Experiments (DOE)
methodology described earlier, which aimed to optimize
the conditions for sulphide recovery from the Cantung tail-
ings, we conducted a series of tests under these conditions.
The results of the experiment using the optimized condi-
tions are shown as experiment CTOP-1 in Figure 7 and
Table 7. Frother was not included in the original reagent
scheme after the initial baseline experiment showed ample
froth thickness, indicating that the addition of Aerofroth
65 was unnecessary. After the optimization was completed,
Aerofroth 65 introduced to assess its efficacy (CTOP-4)
results for this test are summarized in Figure 7 and Table 7.
For further details on this optimization process utilizing
DOE, readers are referred to the thesis authored by Collins
(2023).
The findings presented in Figure 7 indicate that in
experiment CTOP-1, 82% of sulphur was recovered in the
concentrate, yielding a concentrate grade of 29.7%. Upon
introducing the frother Aerofroth 65 in experiment CTOP-
4, with a marginal 1% increase in mass pull to 29%, sul-
phur recovery rose to 87%, resulting in a concentrate grade
extract a sulphide concentrate. This concentrate may then
be dry stacked separately, using an inert material to isolate
it from moisture. This method aims to prevent the sulphide
concentrate from coming into contact with water, thereby
reducing the risk of acid mine drainage. This approach
involves a separate storage solution for the sulphide-rich
fraction of the tailings compared to the rest of the material
(Surrette et al., 2023).
Test charges were subjected to a low intensity magnetic
separator at various magnetic flux intensities of 540, 1020,
and 1650 Gauss and sulphur grade and mass pulls were
measured. A magnetic field strength of 540 Gauss resulted
in the recovery of 11% of the total sample mass. Further
increasing the field strength to 1650 Gauss led to an addi-
tional 9% recovery of the total sample mass. However, upon
analyzing the magnetic fractions recovered, it was observed
that the sulphur and iron grades decreased at higher field
strengths. This indicated that the heightened field strength
most likely led to increased recovery of middlings and
paramagnetic minerals within the magnetic concentrate.
Therefore, it was concluded that the optimal separation
would be achieved with the lowest magnetic flux intensity
of 540 Gauss. Consequently, this intensity was selected
29
30
31
32
33
34
35
0 20 40 60 80 100
S Recovery (%)
CTOP-4 CTOP-1
Figure 7. Sulphur grade (%)versus sulphur recovery (%)in sulphide flotation
Table 7. Total non-sulphate sulphur present in the Cantung tailings after flotation
Experiment
Number
Sulphur Grade of
Tailings, %
SO4 in Tailings
(Ion Chromatography), %
Sulphur in
SO4, %
Non-Sulphate Sulphur
Grade, %
CTOP-1 2.64 7.78 0.297 2.34
CTOP-4 1.96 5.63 0.237 1.72
S
Grade
(%)
to prepare the feed for the subsequent sulphide flotation
experiments.
Building upon the Design of Experiments (DOE)
methodology described earlier, which aimed to optimize
the conditions for sulphide recovery from the Cantung tail-
ings, we conducted a series of tests under these conditions.
The results of the experiment using the optimized condi-
tions are shown as experiment CTOP-1 in Figure 7 and
Table 7. Frother was not included in the original reagent
scheme after the initial baseline experiment showed ample
froth thickness, indicating that the addition of Aerofroth
65 was unnecessary. After the optimization was completed,
Aerofroth 65 introduced to assess its efficacy (CTOP-4)
results for this test are summarized in Figure 7 and Table 7.
For further details on this optimization process utilizing
DOE, readers are referred to the thesis authored by Collins
(2023).
The findings presented in Figure 7 indicate that in
experiment CTOP-1, 82% of sulphur was recovered in the
concentrate, yielding a concentrate grade of 29.7%. Upon
introducing the frother Aerofroth 65 in experiment CTOP-
4, with a marginal 1% increase in mass pull to 29%, sul-
phur recovery rose to 87%, resulting in a concentrate grade
extract a sulphide concentrate. This concentrate may then
be dry stacked separately, using an inert material to isolate
it from moisture. This method aims to prevent the sulphide
concentrate from coming into contact with water, thereby
reducing the risk of acid mine drainage. This approach
involves a separate storage solution for the sulphide-rich
fraction of the tailings compared to the rest of the material
(Surrette et al., 2023).
Test charges were subjected to a low intensity magnetic
separator at various magnetic flux intensities of 540, 1020,
and 1650 Gauss and sulphur grade and mass pulls were
measured. A magnetic field strength of 540 Gauss resulted
in the recovery of 11% of the total sample mass. Further
increasing the field strength to 1650 Gauss led to an addi-
tional 9% recovery of the total sample mass. However, upon
analyzing the magnetic fractions recovered, it was observed
that the sulphur and iron grades decreased at higher field
strengths. This indicated that the heightened field strength
most likely led to increased recovery of middlings and
paramagnetic minerals within the magnetic concentrate.
Therefore, it was concluded that the optimal separation
would be achieved with the lowest magnetic flux intensity
of 540 Gauss. Consequently, this intensity was selected
29
30
31
32
33
34
35
0 20 40 60 80 100
S Recovery (%)
CTOP-4 CTOP-1
Figure 7. Sulphur grade (%)versus sulphur recovery (%)in sulphide flotation
Table 7. Total non-sulphate sulphur present in the Cantung tailings after flotation
Experiment
Number
Sulphur Grade of
Tailings, %
SO4 in Tailings
(Ion Chromatography), %
Sulphur in
SO4, %
Non-Sulphate Sulphur
Grade, %
CTOP-1 2.64 7.78 0.297 2.34
CTOP-4 1.96 5.63 0.237 1.72
S
Grade
(%)