XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 1331
the magnetic product were 63.57%, 93.03% and 59.56%
respectively. Throughout the period, the operational status
of each critical component of the equipment was stable and
satisfactory, operating within the preset ranges.
Full Flowsheet Experiment for Recovering Iron
from Ores
In order to improve the quality of the products obtained in
the continuous and stable operation test and to reduce the
content of the harmful element F in the magnetic products
while recovering as much as possible rare earth minerals
from the non -magnetic products, the subsequent pro-
cessing of the samples treated with HMPT was improved.
A recovery process involving two stages of grinding, two
stages of weak magnetic separation followed by flotation
de -fluorination of the magnetic concentrate was adopted.
This approach was designed to produce a high quality, low
fluorite concentrates and achieve comprehensive mineral
recovery. The quantity – quality flow sheet for the full pro-
cess of the pilot – scale experiment is shown in Figure 9, and
Figure 10 shows the quantity – quality flow sheet for the
flotation de -fluorination of the iron concentrate. After the
HMPT magnetic separation de -fluorination treatment, a
high -quality iron concentrate with a TFe grade of 65.26%
and a total TFe recovery of 80.68% was obtained, with the
F content reduced to below 0.3%. The REO content in
the non -magnetic fraction after magnetic separation was
increased to over 12%, indicating high recovery potential.
Compared to existing recovery processes for this ore, this
method maintains a TFe grade above 65% while increasing
recovery by 25% to 45% and reducing F content by 25%
to 50%. The HMPT magnetic separation -de -fluorina-
tion approach provides a practical, reliable new strategy and
pathway for the recovery of complex polymetallic ores in
the Bayan Obo region.
Analysis of the Products
Chemical and Physical Composition of Flotation
Concentration
Table 3 shows the multi-element assay results of the HMPT
magnetic products after magnetic separation and flotation
de-fluorination. It can be seen that the TFe content of the
magnetic product after HMPT magnetic separation de-flu-
orination can reach 65.26%, with the F content as low as
0.28%. The main impurity, SiO2, is 3.86%, and the harm-
ful elements P and S are both less than 0.1%. Figure 11
shows the XRD spectrum of the defluorinated magnetic
product. The spectrum shows that the diffraction peaks
0 10 20 30 40 50 60 70 80 90 100
0
100
200
300
400
500
600
700
Sample number
Suspension furnace
HMPT room
Suspension furnace
Cooling unit
Roots blower
-4.5
-3.0
-1.5
0.0
1.5
3.0
4.5
HMPT room
Roots blower
Figure 8. Temperatures and pressures of the main parts of the HMPT system during the
continuous and stable operation experiment
Table 3. Results of chemical multi-element analysis (%)
TFe REO FeO CaO MgO SiO
2 Al
2 O
3 S P F K
2 O Na
2 O
65.26 0.93 23.26 0.84 0.43 3.86 0.19 0.07 0.08 0.28 0.01 0.03
Temperature/
Pre
ure/(kPa)
the magnetic product were 63.57%, 93.03% and 59.56%
respectively. Throughout the period, the operational status
of each critical component of the equipment was stable and
satisfactory, operating within the preset ranges.
Full Flowsheet Experiment for Recovering Iron
from Ores
In order to improve the quality of the products obtained in
the continuous and stable operation test and to reduce the
content of the harmful element F in the magnetic products
while recovering as much as possible rare earth minerals
from the non -magnetic products, the subsequent pro-
cessing of the samples treated with HMPT was improved.
A recovery process involving two stages of grinding, two
stages of weak magnetic separation followed by flotation
de -fluorination of the magnetic concentrate was adopted.
This approach was designed to produce a high quality, low
fluorite concentrates and achieve comprehensive mineral
recovery. The quantity – quality flow sheet for the full pro-
cess of the pilot – scale experiment is shown in Figure 9, and
Figure 10 shows the quantity – quality flow sheet for the
flotation de -fluorination of the iron concentrate. After the
HMPT magnetic separation de -fluorination treatment, a
high -quality iron concentrate with a TFe grade of 65.26%
and a total TFe recovery of 80.68% was obtained, with the
F content reduced to below 0.3%. The REO content in
the non -magnetic fraction after magnetic separation was
increased to over 12%, indicating high recovery potential.
Compared to existing recovery processes for this ore, this
method maintains a TFe grade above 65% while increasing
recovery by 25% to 45% and reducing F content by 25%
to 50%. The HMPT magnetic separation -de -fluorina-
tion approach provides a practical, reliable new strategy and
pathway for the recovery of complex polymetallic ores in
the Bayan Obo region.
Analysis of the Products
Chemical and Physical Composition of Flotation
Concentration
Table 3 shows the multi-element assay results of the HMPT
magnetic products after magnetic separation and flotation
de-fluorination. It can be seen that the TFe content of the
magnetic product after HMPT magnetic separation de-flu-
orination can reach 65.26%, with the F content as low as
0.28%. The main impurity, SiO2, is 3.86%, and the harm-
ful elements P and S are both less than 0.1%. Figure 11
shows the XRD spectrum of the defluorinated magnetic
product. The spectrum shows that the diffraction peaks
0 10 20 30 40 50 60 70 80 90 100
0
100
200
300
400
500
600
700
Sample number
Suspension furnace
HMPT room
Suspension furnace
Cooling unit
Roots blower
-4.5
-3.0
-1.5
0.0
1.5
3.0
4.5
HMPT room
Roots blower
Figure 8. Temperatures and pressures of the main parts of the HMPT system during the
continuous and stable operation experiment
Table 3. Results of chemical multi-element analysis (%)
TFe REO FeO CaO MgO SiO
2 Al
2 O
3 S P F K
2 O Na
2 O
65.26 0.93 23.26 0.84 0.43 3.86 0.19 0.07 0.08 0.28 0.01 0.03
Temperature/
Pre
ure/(kPa)