XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 1335
respectively. The magnetic concentrate contains mainly
iron (Fe) and oxygen (O) elements, with a small amount
of silicon (Si), while other impurity elements are hardly
observable. The main phase in the magnetic tailings is fluo-
rite, together with a significant amount of rare earth oxides
and a small amount of iron silicate. This indicates that the
separation of magnetic and non-magnetic products after
HMPT treatment is effective and that there is potential for
recovery of fluorite and rare earth components.
Magnetic Performance of the Products on HMPT
The transformation of the iron phases also results in changes
in the magnetic properties of the products, as shown in
Figure 15 for different HMPT stages. With increasing mag-
netic field strength, the unit mass magnetic moment for
raw ore, transformed product, magnetic concentrate and
non-magnetic products were 7.23 A·m2/kg, 25.39 A·m2/
kg, 46.10 A·m2/kg and 0.04 A·m2/kg, respectively. In addi-
tion, the specific susceptibility curves of these four products
show similar positions and trends, initially increasing and
then decreasing with the increase of the external magnetic
field strength. The maximum specific magnetization coeffi-
cients for these products are 0.006×10–3 m3/kg, 0.021×10–3
m3/kg, 0.034×10–3 m3/kg and 0.003×10–5 m3/kg, respec-
tively. These results indicate that weakly magnetic, diffi-
cult-to-select iron minerals can be transformed into more
strongly magnetic iron minerals by HMPT treatment. In
addition, they can be separated from non-magnetic com-
ponents using lower magnetic field strengths.
CONCLUSIONS
This study investigated the pilot-scale recovery of low-grade,
difficult-to-select iron ores from BOLIO using Hydrogen-
based Mineral Phase Transformation (HMPT) technology
and equipment. Under optimal conditions (120 kg/h feed-
ing rate, 500°C, 3.5 m3/h gas flow, 22.5% concentrate), ore
samples were prepared and then subjected to stage grind-
ing, stage magnetic separation and flotation. This process
resulted in an iron concentrate with an iron content of
65.26%, a total process recovery of 80.68% and an F con-
tent of 0.28%. The HMPT process converted weakly mag-
netic iron ores to strongly magnetic iron ores, significantly
Figure 14. The map scanning images of magnetic concentrate
respectively. The magnetic concentrate contains mainly
iron (Fe) and oxygen (O) elements, with a small amount
of silicon (Si), while other impurity elements are hardly
observable. The main phase in the magnetic tailings is fluo-
rite, together with a significant amount of rare earth oxides
and a small amount of iron silicate. This indicates that the
separation of magnetic and non-magnetic products after
HMPT treatment is effective and that there is potential for
recovery of fluorite and rare earth components.
Magnetic Performance of the Products on HMPT
The transformation of the iron phases also results in changes
in the magnetic properties of the products, as shown in
Figure 15 for different HMPT stages. With increasing mag-
netic field strength, the unit mass magnetic moment for
raw ore, transformed product, magnetic concentrate and
non-magnetic products were 7.23 A·m2/kg, 25.39 A·m2/
kg, 46.10 A·m2/kg and 0.04 A·m2/kg, respectively. In addi-
tion, the specific susceptibility curves of these four products
show similar positions and trends, initially increasing and
then decreasing with the increase of the external magnetic
field strength. The maximum specific magnetization coeffi-
cients for these products are 0.006×10–3 m3/kg, 0.021×10–3
m3/kg, 0.034×10–3 m3/kg and 0.003×10–5 m3/kg, respec-
tively. These results indicate that weakly magnetic, diffi-
cult-to-select iron minerals can be transformed into more
strongly magnetic iron minerals by HMPT treatment. In
addition, they can be separated from non-magnetic com-
ponents using lower magnetic field strengths.
CONCLUSIONS
This study investigated the pilot-scale recovery of low-grade,
difficult-to-select iron ores from BOLIO using Hydrogen-
based Mineral Phase Transformation (HMPT) technology
and equipment. Under optimal conditions (120 kg/h feed-
ing rate, 500°C, 3.5 m3/h gas flow, 22.5% concentrate), ore
samples were prepared and then subjected to stage grind-
ing, stage magnetic separation and flotation. This process
resulted in an iron concentrate with an iron content of
65.26%, a total process recovery of 80.68% and an F con-
tent of 0.28%. The HMPT process converted weakly mag-
netic iron ores to strongly magnetic iron ores, significantly
Figure 14. The map scanning images of magnetic concentrate
