XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2465
• Primary and secondary grind rougher flotation con-
dition 1—85% L(liquid)SIBX +15% DTP (STD)
– referred to as PGRF 1 and SGRF 1 in the text,
respectively.
• Primary and secondary grind rougher flotation con-
dition 2—45% LSIBX +45% DTC (A) +10%
DTP– referred to as PGRF 2 and SGRF 2 in the
text, respectively.
• Primary and secondary grind rougher flotation con-
dition 3—50% LSIBX +50% (50% DTC (C) +
50% DTC (A):DTC (B)) – referred to as PGRF 3
and SGRF 3 in the text, respectively.
• Primary and secondary grind rougher flotation con-
dition 4—50% LSIBX +35% (50% DTC (C) +
50% DTC (A):DTC (B)) +15% DTP – referred to
as PGRF 4 and SGRF 4 in the text, respectively.
The depressant added for the primary and secondary grind
rougher flotation was Norilose 8058 at a dosage of 75 g/t
and 25 g/t, respectively and frother was Senfroth 516 at a
dosage of 50g/t. and 10g/t, respectively.
Mineralogy Techniques and Sample Preparation
X-ray diffraction (XRD) analysis and QEMSCAN bulk
modal analysis (BMA) were used to identify and quantify
bulk mineral abundances. PGM deportment was carried
out using QEMSCAN Trace Mineral Search (TMS) and
FEG-MLA, and BMS deportment using the QEMSCAN
Specific Mineral Search (SMS). The QEMSCAN technique
uses an automated sparse phase liberation measurement to
identify and characterise the grains of interest in a sample
block. This method detects particles with a high backscat-
tered electron image intensity using set grey levels. The
particle detected is then analysed using energy dispersive
X-ray analysis and information on the particle of interest
and other related phases is collected and stored. The FEG
Mineral Liberation Analyzer (MLA) technique locates the
PGMs by means of their high backscattered electron (BSE)
intensity and identified using automated energy disper-
sive spectrometry. The number of PGM and BMS grains
and particles collected were statistically sufficient for the
techniques.
RESULTS AND DISCUSSION
Batch Flotation Testwork
The batch flotation testwork was conducted on a Platreef
ore from South Africa. Previous data (Shackleton et al.
2023 – paper in print) highlighted that DTP and DTC
tended to collect minerals from different size classes where
the P80 for SIBX+DTP ratios was 20–25 μm and the P80
for SIBX+DTC ratios was 15–20 μm for the first concen-
trate after 5 minutes of collection. Therefore this study was
undertaken to determine whether particle size and/or the
collector type affect the metallurgical outcome with respect
to grade and/or recovery. These new collectors were made
up of varying types and ratios of SIBX, DTP and DTC to
specifically target the minerals in the ore during the pri-
mary and secondary grind rougher flotation.
The metallurgical data shows a significant increase in
flotation kinetics during the early stages of flotation espe-
cially for the 6E PGM and Ni for all the AECI collectors
compared to the standard (Figures 2A, 3A and 4A). The
PGRF 3 and SGRF 3 as well as the PGRF 4 and SGRF 4
gave the highest overall 6E PGM recoveries compared to the
standard (PGFR 1 and SGFR 1) and condition 2 (PGRF
2 and SGRF 2). Whereas the highest overall Cu and Ni
recoveries were achieved for PGRF 4 SGRF 4 and PGRF
3 SGRF 3, respectively, (Figures 2A, 3A and 4A). Figures
2B, 3B and 4B show the 6E PGM, Cu and Ni recovery
versus mass pull curves and highlight that mass pull was not
the driver for the improved recoveries observed.
Figures 5A, B and C show the cumulative percentage
change in the 6E PGM, Cu, Ni grade and recovery for all
the AECI collectors evaluated compared to the standard
conditions (PGRF 1 and SGRF 1) for the 1st and final
concentrates for the primary and secondary grind rougher
flotation, respectively. The data highlights the significant
increases in both grade and recovery, particularly for the
PGM minerals when using the AECI collectors evaluated
compared to the standard conditions.
Bulk Modal Data
The bulk mineral assemblage of the samples (Figure 6)
shows that the mineralogy comprised mainly pyroxene (~50
mass %)and feldspar (~30 mass %)making it a feldspathic
pyroxenite (Schouwstra et al., 2017). Chlorite is present in
minor amounts (~6 mass %).The rest of the mineral spe-
cies are present in low amounts (5 mass %)and include
mostly quartz, talc, serpentine and olivine. The BMS make
up 0.8 mass %of the feed. The primary and secondary
grind rougher flotation concentrates show that there was an
increase in sulphides detected, while the amount of feldspar
decreased substantially, however, there was an increase in
pyroxene content across all samples. Other silicates include
a fine-grained mix that was too fine to be discriminated.
PGM Deportment/Speciation, Grain Size Distribution
(GSD) and Liberation Data
Figure 7A provides the results of the PGM species detected
and include PGE tellurides, PGE arsenides, PGE sulphides,
• Primary and secondary grind rougher flotation con-
dition 1—85% L(liquid)SIBX +15% DTP (STD)
– referred to as PGRF 1 and SGRF 1 in the text,
respectively.
• Primary and secondary grind rougher flotation con-
dition 2—45% LSIBX +45% DTC (A) +10%
DTP– referred to as PGRF 2 and SGRF 2 in the
text, respectively.
• Primary and secondary grind rougher flotation con-
dition 3—50% LSIBX +50% (50% DTC (C) +
50% DTC (A):DTC (B)) – referred to as PGRF 3
and SGRF 3 in the text, respectively.
• Primary and secondary grind rougher flotation con-
dition 4—50% LSIBX +35% (50% DTC (C) +
50% DTC (A):DTC (B)) +15% DTP – referred to
as PGRF 4 and SGRF 4 in the text, respectively.
The depressant added for the primary and secondary grind
rougher flotation was Norilose 8058 at a dosage of 75 g/t
and 25 g/t, respectively and frother was Senfroth 516 at a
dosage of 50g/t. and 10g/t, respectively.
Mineralogy Techniques and Sample Preparation
X-ray diffraction (XRD) analysis and QEMSCAN bulk
modal analysis (BMA) were used to identify and quantify
bulk mineral abundances. PGM deportment was carried
out using QEMSCAN Trace Mineral Search (TMS) and
FEG-MLA, and BMS deportment using the QEMSCAN
Specific Mineral Search (SMS). The QEMSCAN technique
uses an automated sparse phase liberation measurement to
identify and characterise the grains of interest in a sample
block. This method detects particles with a high backscat-
tered electron image intensity using set grey levels. The
particle detected is then analysed using energy dispersive
X-ray analysis and information on the particle of interest
and other related phases is collected and stored. The FEG
Mineral Liberation Analyzer (MLA) technique locates the
PGMs by means of their high backscattered electron (BSE)
intensity and identified using automated energy disper-
sive spectrometry. The number of PGM and BMS grains
and particles collected were statistically sufficient for the
techniques.
RESULTS AND DISCUSSION
Batch Flotation Testwork
The batch flotation testwork was conducted on a Platreef
ore from South Africa. Previous data (Shackleton et al.
2023 – paper in print) highlighted that DTP and DTC
tended to collect minerals from different size classes where
the P80 for SIBX+DTP ratios was 20–25 μm and the P80
for SIBX+DTC ratios was 15–20 μm for the first concen-
trate after 5 minutes of collection. Therefore this study was
undertaken to determine whether particle size and/or the
collector type affect the metallurgical outcome with respect
to grade and/or recovery. These new collectors were made
up of varying types and ratios of SIBX, DTP and DTC to
specifically target the minerals in the ore during the pri-
mary and secondary grind rougher flotation.
The metallurgical data shows a significant increase in
flotation kinetics during the early stages of flotation espe-
cially for the 6E PGM and Ni for all the AECI collectors
compared to the standard (Figures 2A, 3A and 4A). The
PGRF 3 and SGRF 3 as well as the PGRF 4 and SGRF 4
gave the highest overall 6E PGM recoveries compared to the
standard (PGFR 1 and SGFR 1) and condition 2 (PGRF
2 and SGRF 2). Whereas the highest overall Cu and Ni
recoveries were achieved for PGRF 4 SGRF 4 and PGRF
3 SGRF 3, respectively, (Figures 2A, 3A and 4A). Figures
2B, 3B and 4B show the 6E PGM, Cu and Ni recovery
versus mass pull curves and highlight that mass pull was not
the driver for the improved recoveries observed.
Figures 5A, B and C show the cumulative percentage
change in the 6E PGM, Cu, Ni grade and recovery for all
the AECI collectors evaluated compared to the standard
conditions (PGRF 1 and SGRF 1) for the 1st and final
concentrates for the primary and secondary grind rougher
flotation, respectively. The data highlights the significant
increases in both grade and recovery, particularly for the
PGM minerals when using the AECI collectors evaluated
compared to the standard conditions.
Bulk Modal Data
The bulk mineral assemblage of the samples (Figure 6)
shows that the mineralogy comprised mainly pyroxene (~50
mass %)and feldspar (~30 mass %)making it a feldspathic
pyroxenite (Schouwstra et al., 2017). Chlorite is present in
minor amounts (~6 mass %).The rest of the mineral spe-
cies are present in low amounts (5 mass %)and include
mostly quartz, talc, serpentine and olivine. The BMS make
up 0.8 mass %of the feed. The primary and secondary
grind rougher flotation concentrates show that there was an
increase in sulphides detected, while the amount of feldspar
decreased substantially, however, there was an increase in
pyroxene content across all samples. Other silicates include
a fine-grained mix that was too fine to be discriminated.
PGM Deportment/Speciation, Grain Size Distribution
(GSD) and Liberation Data
Figure 7A provides the results of the PGM species detected
and include PGE tellurides, PGE arsenides, PGE sulphides,