558 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
utilization of magnetite ore resources in arid and severely
cold regions (Ghaffour et al., 2013). Dry magnetic sepa-
ration (DMS) technology, without water consumption,
provides an effective way for the utilization of iron ores
in these water-scarce areas. Meanwhile, DMS has some
incomparable advantages over wet magnetic separations
for example, the products produced from the DMS process
do not require filtration or antifreeze measures (Ezhov and
Shvaljov, 2015 Tripathy et al., 2017). At present, the DMS
process is generally applied before wet magnetic separation
process for instance, a DMS separator was employed for
the pre-separation of a low-grade magnetite ore prior to
grinding operations (Sun et al., 2022).
The DMS separators in the beneficiation industry of
ores are effective in separating iron ores with large particle
size. However, their separation efficiency is negligible for
fine-grained mineral powders (Tripathy and Suresh, 2017
Yi et al., 2022). Such limitation is primarily attributed to
the fact that the electrostatic force and Van der Waals force
become the main interactive forces among powdered par-
ticles, which hinders their effective dispersion in a DMS
process (Hu, 2013). In addition, for the magnetite pow-
ders, they are easy to form magnetic aggregates in the DMS
process due to their large remanence, thus further deterio-
rating the DMS performance (Zheng, 1995). In order to
improve the separation selectivity of DMS process to fine
particles, a dry centrifugal magnetic separator (cDMS) was
innovatively developed, and in this investigation it was used
for pre-separating a low-grade fine magnetite ore to evalu-
ate its separation performance.
EXPERIMENTAL
cDMS-1000 Separator
In this investigation, a full-scale cDMS-1000 separator
was used to separate a fine magnetite ore. It adopts a per-
manent magnet system, and operates continuously, with a
rapid separation process and large processing capacity. The
main technical parameters of the separator were shown in
Table 1.
It can be seen from Figure 1, the separator is mainly
composed of support frame, separation cone, magnets,
driving mechanism, feeder, dust cover, and receiving hop-
pers. The separation cone speed and the magnetic induc-
tion in the separation area of the separator are continuously
adjustable. When the separator is being operated, the mag-
netic induction on the separation cone surface and the
separation cone speed are firstly adjusted to the required
values. Then, magnetite powders are fed from the feeder
onto the cone surface for separation. During this stage, the
rotating separation cone continuously produces a tangen-
tial friction acting on the particles, fully facilitating their
looseness. Finally, under the action of centrifugal force,
non-magnetic particles are preferentially thrown out of the
separation cone to obtain a non-magnetic product (tail-
ings) magnetic particles subjected to magnetic force would
overcome the centrifugal force acting onto the particles,
throwing out of the cone to become a magnetic product
(concentrate), when they rotate with the separation cone to
the non-magnetic field zone.
Materials
A magnetite ore sourced from the southwest Fujian in
China was used for the cDMS experiments. The ore has
the maximum particle size of 150 mm, with its chemi-
cal compositions illustrated in Table 2. It can be seen that
the ore assays 33.60% Fe and 14.28% FeO, respectively.
The main impurity components in the ore are SiO2, CaO,
Al2O3 and MgO and their contents are 32.70%, 11.71%,
Table 1. Main technical parameters of full-scale cDMS-1000 separator
Magnetic
Induction (T)
Feed Frequency
(Hz)
Cone Rotation Speed
(rpm)
Feed Particle Size
(mm)
Maximum Processing
Capacity (t/h)
0–0.3 0–50 0–200 0–8.0 4.0
Figure 1. Physical image of full-scale cDMS-1000 separator
utilization of magnetite ore resources in arid and severely
cold regions (Ghaffour et al., 2013). Dry magnetic sepa-
ration (DMS) technology, without water consumption,
provides an effective way for the utilization of iron ores
in these water-scarce areas. Meanwhile, DMS has some
incomparable advantages over wet magnetic separations
for example, the products produced from the DMS process
do not require filtration or antifreeze measures (Ezhov and
Shvaljov, 2015 Tripathy et al., 2017). At present, the DMS
process is generally applied before wet magnetic separation
process for instance, a DMS separator was employed for
the pre-separation of a low-grade magnetite ore prior to
grinding operations (Sun et al., 2022).
The DMS separators in the beneficiation industry of
ores are effective in separating iron ores with large particle
size. However, their separation efficiency is negligible for
fine-grained mineral powders (Tripathy and Suresh, 2017
Yi et al., 2022). Such limitation is primarily attributed to
the fact that the electrostatic force and Van der Waals force
become the main interactive forces among powdered par-
ticles, which hinders their effective dispersion in a DMS
process (Hu, 2013). In addition, for the magnetite pow-
ders, they are easy to form magnetic aggregates in the DMS
process due to their large remanence, thus further deterio-
rating the DMS performance (Zheng, 1995). In order to
improve the separation selectivity of DMS process to fine
particles, a dry centrifugal magnetic separator (cDMS) was
innovatively developed, and in this investigation it was used
for pre-separating a low-grade fine magnetite ore to evalu-
ate its separation performance.
EXPERIMENTAL
cDMS-1000 Separator
In this investigation, a full-scale cDMS-1000 separator
was used to separate a fine magnetite ore. It adopts a per-
manent magnet system, and operates continuously, with a
rapid separation process and large processing capacity. The
main technical parameters of the separator were shown in
Table 1.
It can be seen from Figure 1, the separator is mainly
composed of support frame, separation cone, magnets,
driving mechanism, feeder, dust cover, and receiving hop-
pers. The separation cone speed and the magnetic induc-
tion in the separation area of the separator are continuously
adjustable. When the separator is being operated, the mag-
netic induction on the separation cone surface and the
separation cone speed are firstly adjusted to the required
values. Then, magnetite powders are fed from the feeder
onto the cone surface for separation. During this stage, the
rotating separation cone continuously produces a tangen-
tial friction acting on the particles, fully facilitating their
looseness. Finally, under the action of centrifugal force,
non-magnetic particles are preferentially thrown out of the
separation cone to obtain a non-magnetic product (tail-
ings) magnetic particles subjected to magnetic force would
overcome the centrifugal force acting onto the particles,
throwing out of the cone to become a magnetic product
(concentrate), when they rotate with the separation cone to
the non-magnetic field zone.
Materials
A magnetite ore sourced from the southwest Fujian in
China was used for the cDMS experiments. The ore has
the maximum particle size of 150 mm, with its chemi-
cal compositions illustrated in Table 2. It can be seen that
the ore assays 33.60% Fe and 14.28% FeO, respectively.
The main impurity components in the ore are SiO2, CaO,
Al2O3 and MgO and their contents are 32.70%, 11.71%,
Table 1. Main technical parameters of full-scale cDMS-1000 separator
Magnetic
Induction (T)
Feed Frequency
(Hz)
Cone Rotation Speed
(rpm)
Feed Particle Size
(mm)
Maximum Processing
Capacity (t/h)
0–0.3 0–50 0–200 0–8.0 4.0
Figure 1. Physical image of full-scale cDMS-1000 separator