XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3627
spirals and the undersize material from the 150 µm classifi-
cation are fed into the secondary grinding circuit, ensuring
further liberation of the particles. The magnetite present
in the ground product is recovered through a low-intensity
magnetic separation circuit (LIMS) followed by flotation
(Wang, 2022). On the other hand, to recover the hema-
tite from the tailings of LIMS stage, a different circuit is
used, consisting of wet high-intensity magnetic separation
(WHIMS), followed by reverse cationic flotation (Xiong,
2015 and Filippov, 2014).
Trying to confirm the results obtained in bench scale
(Mesquita, 2021) and defining the best configuration for
the pre-concentration circuit, a series of pilot scale tests
using spirals were performed together with a complete
characterization of the products generated (Figure 3).
During the work, three different configurations of circuits
were evaluated, containing respectively “rougher,” “rougher
+cleaner” and “rougher +cleaner +recleaner” stages. This
approach allowed for a thorough assessment of the impor-
tance of having a pre-concentration stage when processing
a low-grade ore.
MATERIALS &METHODS
Sample
The sample selected for the study corresponds to a repre-
sentative aliquot of Mont Reed pre-concentration feed
collected during the pilot campaign testwork executed
with the ore. The material corresponds to the oversize of
a 150 µm screening operation performed with Mont Reed
ore ground up to 1mm. The chemical analysis of the sam-
ple is presented in Table 3 and its particle size distribution
(PSD) in Figure 3.
Powder X-Ray Diffraction
Powder X-ray diffraction (XRD) analyses were performed
using a Bruker D2 Phaser diffractometer, which features a
goniometer in Bragg-Brentano geometry, a Co Kα (1.789
Å) source, and a Lynxeye 1D silicon-drift detector. Prior to
the acquisition, the samples are ground to a top size of 63µm
using a ring mill. Diffractograms were acquired as coupled
2θ/θ scans on the 7–80°2θ range, with a step size of 0.02°
2θ, a dwell time of 1.5 sec. per step. Phase identification
Figure 3. Methodology
Table 3. Grinding feed sample chemical analysis
Grade, %
Fe FeO SiO
2 Al
2 O
3 CaO MgO TiO
2 P Mn S Na
2 O K
2 O LOI
30.44 11.17 48.17 0.10 2.93 2.78 0.01 0.007 0.77 0.011 0.08 0.02 1.78
spirals and the undersize material from the 150 µm classifi-
cation are fed into the secondary grinding circuit, ensuring
further liberation of the particles. The magnetite present
in the ground product is recovered through a low-intensity
magnetic separation circuit (LIMS) followed by flotation
(Wang, 2022). On the other hand, to recover the hema-
tite from the tailings of LIMS stage, a different circuit is
used, consisting of wet high-intensity magnetic separation
(WHIMS), followed by reverse cationic flotation (Xiong,
2015 and Filippov, 2014).
Trying to confirm the results obtained in bench scale
(Mesquita, 2021) and defining the best configuration for
the pre-concentration circuit, a series of pilot scale tests
using spirals were performed together with a complete
characterization of the products generated (Figure 3).
During the work, three different configurations of circuits
were evaluated, containing respectively “rougher,” “rougher
+cleaner” and “rougher +cleaner +recleaner” stages. This
approach allowed for a thorough assessment of the impor-
tance of having a pre-concentration stage when processing
a low-grade ore.
MATERIALS &METHODS
Sample
The sample selected for the study corresponds to a repre-
sentative aliquot of Mont Reed pre-concentration feed
collected during the pilot campaign testwork executed
with the ore. The material corresponds to the oversize of
a 150 µm screening operation performed with Mont Reed
ore ground up to 1mm. The chemical analysis of the sam-
ple is presented in Table 3 and its particle size distribution
(PSD) in Figure 3.
Powder X-Ray Diffraction
Powder X-ray diffraction (XRD) analyses were performed
using a Bruker D2 Phaser diffractometer, which features a
goniometer in Bragg-Brentano geometry, a Co Kα (1.789
Å) source, and a Lynxeye 1D silicon-drift detector. Prior to
the acquisition, the samples are ground to a top size of 63µm
using a ring mill. Diffractograms were acquired as coupled
2θ/θ scans on the 7–80°2θ range, with a step size of 0.02°
2θ, a dwell time of 1.5 sec. per step. Phase identification
Figure 3. Methodology
Table 3. Grinding feed sample chemical analysis
Grade, %
Fe FeO SiO
2 Al
2 O
3 CaO MgO TiO
2 P Mn S Na
2 O K
2 O LOI
30.44 11.17 48.17 0.10 2.93 2.78 0.01 0.007 0.77 0.011 0.08 0.02 1.78