XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 559
3.38% and 1.89% respectively moreover, the S content in
the ore is relatively high, reaching 0.463%. From Table 3,
the iron-bearing minerals mainly exist in magnetite, silicate
and hematite, accounting for 85.04%, 10.12% and 4.02%
of total iron, respectively.
Methods
To investigate the effect of feed particle size on the sepa-
ration performance of the full-scale cDMS-1000 separa-
tor, the magnetite ore was crushed using a jaw crusher to
reduce the particles size of the ore to below 8.0 mm. From
this particle size, five particle sizes (–2.0 mm, –0.425 mm,
–0.10 mm, –0.074 mm, and –0.037 mm) were respec-
tively prepared through RK/3ZM-100 vibration grinding
process.
For each cDMS experiment, 10 kg ore was fed to the
full-scale cDMS-1000 separator within 30 s. Magnetic
induction for the cDMS experiments was optimized at
0.21 T through single factor experiments before this inves-
tigation. For all cDMS experiments, the grades of total iron
and magnetite iron in magnetite (concentrate) and non-
magnetic (tailings) products from the cDMS process were
analyzed. The separation performance of the cDMS separa-
tor was evaluated on the concentrate mass yield, concen-
trate grade, and magnetite recovery. The concentrate mass
yield and iron recovery were calculated using Eqs. (1), (2),
and (3), respectively.
Mass yield(%) 100% Fe O O
Fe O O
3 4 3 4
3 4 3 4 #b iFe
a iFe
=-
-
(1)
100% Fe recov ery(%)
Mass yield #
#aFe
iFe
=(2)
)
100%
Fe O
recov ery(%) O
Fe3 O O4)
O4
Fe O O
3 4
3 4
4
3 4 3 4
#(b
#(a
#aFe
iFe3
bFe3
iFe
=
-
-
(3)
where, αFe and αFe3O4 are the total iron and magnetite
iron grades of feed, respectively βFe and βFe3O4 are the
total iron and magnetite iron grades of concentrate, respec-
tively and θFe and θFe3O4 are the total iron and magnetite
iron grades of tailings, respectively.
RESULTS AND DISCUSSION
cDMS Performance as a Function of Feed Particle Size
In this section, the performance of the full-scale cDMS-
1000 separator for the separation of magnetite ore with dif-
ferent feed particle sizes were comparatively investigated at a
separation cone speed of 60 rpm. The results obtained from
the cDMS process in terms of total iron and magnetite iron
recoveries were displayed in Figures 2 and 3, respectively. It
was found that the feed particle size has a significant impact
on the cDMS performance of the magnetite ore. The con-
centrate mass was slightly declined with decrease in the feed
particle size from –2.0 mm to –0.10 mm below this range,
the mass was sharply increased. Meanwhile, the total iron
recovery of concentrate followed a similar trend to that of
concentrate mass, as shown in Figure 2.
For the magnetite iron recovery, the cDMS separator
achieved the recovery higher than 96.0% for all the feed
particle sizes investigated. Moreover, with decrease in the
feed particle size, the magnetite iron grade in concentrate
was gradually increased from 39.15% for –2.0 mm feed
to the highest of 41.21% for –0.10 mm feed, and then it
was decreased significantly to the lowest grade of 35.95%
for –0.037 mm feed. Correspondingly, the magnetite
iron grade in tailings was firstly decreased from 3.11% to
1.13%, and then was significantly increased to 2.76%, as
shown in Figure 3. The increase in the magnetite iron grade
of concentrate with the increasingly finer feed particle size
from –2.0 mm to –0.10 mm may be attributed to the
improved liberation of magnetite in finer feed. However, as
the feed consistently becomes finer and finer, the centrifu-
gal force acting onto the magnetite particles gets weaker
and weaker. Due to this fact, some gangue particles and
poorly intergrown particles can not be efficiently separated
Table 2. Chemical composition of material (wt%)
TFe FeO CaO MgO Al
2 O
3 SiO
2 S P LOI
33.60 14.28 11.71 1.89 3.38 32.70 0.463 0.006 3.03
*LOI=Loss on ignition.
Table 3. Iron phase analysis of material
Iron Phase Fe in Magnetite Fe in Siderite Fe in Hematite Fe in Silicate Fe in Sulfide
Content (wt.%) 28.57 0.025 1.36 3.40 0.24
Distribution (%)85.04 0.074 4.05 10.12 0.71
3.38% and 1.89% respectively moreover, the S content in
the ore is relatively high, reaching 0.463%. From Table 3,
the iron-bearing minerals mainly exist in magnetite, silicate
and hematite, accounting for 85.04%, 10.12% and 4.02%
of total iron, respectively.
Methods
To investigate the effect of feed particle size on the sepa-
ration performance of the full-scale cDMS-1000 separa-
tor, the magnetite ore was crushed using a jaw crusher to
reduce the particles size of the ore to below 8.0 mm. From
this particle size, five particle sizes (–2.0 mm, –0.425 mm,
–0.10 mm, –0.074 mm, and –0.037 mm) were respec-
tively prepared through RK/3ZM-100 vibration grinding
process.
For each cDMS experiment, 10 kg ore was fed to the
full-scale cDMS-1000 separator within 30 s. Magnetic
induction for the cDMS experiments was optimized at
0.21 T through single factor experiments before this inves-
tigation. For all cDMS experiments, the grades of total iron
and magnetite iron in magnetite (concentrate) and non-
magnetic (tailings) products from the cDMS process were
analyzed. The separation performance of the cDMS separa-
tor was evaluated on the concentrate mass yield, concen-
trate grade, and magnetite recovery. The concentrate mass
yield and iron recovery were calculated using Eqs. (1), (2),
and (3), respectively.
Mass yield(%) 100% Fe O O
Fe O O
3 4 3 4
3 4 3 4 #b iFe
a iFe
=-
-
(1)
100% Fe recov ery(%)
Mass yield #
#aFe
iFe
=(2)
)
100%
Fe O
recov ery(%) O
Fe3 O O4)
O4
Fe O O
3 4
3 4
4
3 4 3 4
#(b
#(a
#aFe
iFe3
bFe3
iFe
=
-
-
(3)
where, αFe and αFe3O4 are the total iron and magnetite
iron grades of feed, respectively βFe and βFe3O4 are the
total iron and magnetite iron grades of concentrate, respec-
tively and θFe and θFe3O4 are the total iron and magnetite
iron grades of tailings, respectively.
RESULTS AND DISCUSSION
cDMS Performance as a Function of Feed Particle Size
In this section, the performance of the full-scale cDMS-
1000 separator for the separation of magnetite ore with dif-
ferent feed particle sizes were comparatively investigated at a
separation cone speed of 60 rpm. The results obtained from
the cDMS process in terms of total iron and magnetite iron
recoveries were displayed in Figures 2 and 3, respectively. It
was found that the feed particle size has a significant impact
on the cDMS performance of the magnetite ore. The con-
centrate mass was slightly declined with decrease in the feed
particle size from –2.0 mm to –0.10 mm below this range,
the mass was sharply increased. Meanwhile, the total iron
recovery of concentrate followed a similar trend to that of
concentrate mass, as shown in Figure 2.
For the magnetite iron recovery, the cDMS separator
achieved the recovery higher than 96.0% for all the feed
particle sizes investigated. Moreover, with decrease in the
feed particle size, the magnetite iron grade in concentrate
was gradually increased from 39.15% for –2.0 mm feed
to the highest of 41.21% for –0.10 mm feed, and then it
was decreased significantly to the lowest grade of 35.95%
for –0.037 mm feed. Correspondingly, the magnetite
iron grade in tailings was firstly decreased from 3.11% to
1.13%, and then was significantly increased to 2.76%, as
shown in Figure 3. The increase in the magnetite iron grade
of concentrate with the increasingly finer feed particle size
from –2.0 mm to –0.10 mm may be attributed to the
improved liberation of magnetite in finer feed. However, as
the feed consistently becomes finer and finer, the centrifu-
gal force acting onto the magnetite particles gets weaker
and weaker. Due to this fact, some gangue particles and
poorly intergrown particles can not be efficiently separated
Table 2. Chemical composition of material (wt%)
TFe FeO CaO MgO Al
2 O
3 SiO
2 S P LOI
33.60 14.28 11.71 1.89 3.38 32.70 0.463 0.006 3.03
*LOI=Loss on ignition.
Table 3. Iron phase analysis of material
Iron Phase Fe in Magnetite Fe in Siderite Fe in Hematite Fe in Silicate Fe in Sulfide
Content (wt.%) 28.57 0.025 1.36 3.40 0.24
Distribution (%)85.04 0.074 4.05 10.12 0.71