3678 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
rate increased, accompanied by a reduction in the content of
silica and acid-insoluble substances in the concentrate. This
is because grinding dissociates some magnetite-conjoined
bodies from the magnetite and gangue minerals. Impurities
were thus removed again through magnetic separation.
At the second-stage grinding size of 90% –30 μm, an
iron concentrate with a grade of 71.87% Fe, an acid-insol-
uble content of 0.20%, and a SiO2 content of 0.33% was
obtained from the second-stage electromagnetic concentra-
tion. Then, a reverse flotation test was conducted to further
remove the impurity from the iron concentrate. The effects
of collector DJW-1 dosages of 100, 200, and 300 g/t on the
impurity removal in EBC were respectively investigated. As
shown in Figure 6(b), the results show that increasing the
amount of collector had no noticeable impact on the total
Fe grade of the flotation concentrate however, the content
of silica and acid-insoluble matter gradually decreased. This
occurred because chemical and hydrogen bond adsorption
occurred between the amino groups in DJW-1 and the
quartz surface (Luo et al., 2018). As a result, the hydro-
phobicity of the quartz surface was enhanced, which was
reflected in its enhanced floatability. From this test series,
the optimum collector dosage was determined to be
200 g/t. Chemical multi-element analysis was performed
on the obtained flotation concentrate, and the results are
shown in Table 8.
Based on the above results, the pre-concentration and
magnetic separation-reverse flotation process requirements
had been determined to prepare ultra-purity iron concen-
trate. As can be seen from Figure 7, multiple intermediate
and final products can be obtained by applying this process.
The total Fe grades of the pre-concentration and weak mag-
netic separation tailings were 28.11% and 24.64% respec-
tively. The iron minerals were closely locked in the gangue
minerals and the particle size was relatively delicate, so they
are discarded.
The grades of middling 1, 2, and reverse flotation con-
centrate are of economic interest. Because these grades dif-
fer, it is necessary to classify the products and designate the
appropriate off-take market according to the standards of
different grades of iron concentrates. Applying this treat-
ment strategy can optimize the iron ore industrial structure,
extend the iron ore industrial chain, and achieve high-qual-
ity and optimized utilization of China’s iron ore.
Pilot-scale continuous and industrial-scale production
was carried out to further verify the preparation effect of
ultra-purity iron concentrate, which is shown in Figure 8.
Two cleaning stages were added to the reverse flotation
operation to make the flotation concentrate meet the
requirements of ultra-purity iron concentrate. The test
results show that the process can operate stably, and the
beneficiation indicators meet the desired quality standard
80 85 90 95
0.0
0.2
20
40
60
80
100
TFe grade TFe recovery SiO2 grade Acid insoluble matter
(a)
100 200 300
0.0
0.2
20
40
60
80
100
DJW-1 dosage (mg/L)
TFe grade TFe recovery
SiO2 grade Al2O3 grade Acid insoluble matter
(b)
Figure 6. Test results of (a) second-stage electromagnetic concentration, left, and (b) effect of DJW-1 dosage on impurity
removal from second-stage electromagnetic concentration concentrate
Table 8. Chemical composition analysis of flotation concentrates (%)
Composition Total Fe CaO MgO SiO
2 Al
2 O
3 S P K /(g/t)
Contents 71.88 0.024 0.008 0.30 0.15 0.0092 0.0020 0.0061
Composition Na TiO2 Mn Cu Pb Zn Acid Insoluble Matter
Contents 0.0072 0.032 0.005 0.0002 0.0012 0.0024 0.19
71.81 71.97 71.87 71.92
97.19 96.33 96.05 96.21
0.39 0.37 0.33 0.34 0.28 0.21 0.2 0.2
Grade/Recov
er(%)
y
71.81 71.88 72.28
93.58
70.71
51.75
0.35 0.3 0.3 0.15 0.15 0.14 0.19 0.19 0.18
Grade/Recov
er(%)
y
rate increased, accompanied by a reduction in the content of
silica and acid-insoluble substances in the concentrate. This
is because grinding dissociates some magnetite-conjoined
bodies from the magnetite and gangue minerals. Impurities
were thus removed again through magnetic separation.
At the second-stage grinding size of 90% –30 μm, an
iron concentrate with a grade of 71.87% Fe, an acid-insol-
uble content of 0.20%, and a SiO2 content of 0.33% was
obtained from the second-stage electromagnetic concentra-
tion. Then, a reverse flotation test was conducted to further
remove the impurity from the iron concentrate. The effects
of collector DJW-1 dosages of 100, 200, and 300 g/t on the
impurity removal in EBC were respectively investigated. As
shown in Figure 6(b), the results show that increasing the
amount of collector had no noticeable impact on the total
Fe grade of the flotation concentrate however, the content
of silica and acid-insoluble matter gradually decreased. This
occurred because chemical and hydrogen bond adsorption
occurred between the amino groups in DJW-1 and the
quartz surface (Luo et al., 2018). As a result, the hydro-
phobicity of the quartz surface was enhanced, which was
reflected in its enhanced floatability. From this test series,
the optimum collector dosage was determined to be
200 g/t. Chemical multi-element analysis was performed
on the obtained flotation concentrate, and the results are
shown in Table 8.
Based on the above results, the pre-concentration and
magnetic separation-reverse flotation process requirements
had been determined to prepare ultra-purity iron concen-
trate. As can be seen from Figure 7, multiple intermediate
and final products can be obtained by applying this process.
The total Fe grades of the pre-concentration and weak mag-
netic separation tailings were 28.11% and 24.64% respec-
tively. The iron minerals were closely locked in the gangue
minerals and the particle size was relatively delicate, so they
are discarded.
The grades of middling 1, 2, and reverse flotation con-
centrate are of economic interest. Because these grades dif-
fer, it is necessary to classify the products and designate the
appropriate off-take market according to the standards of
different grades of iron concentrates. Applying this treat-
ment strategy can optimize the iron ore industrial structure,
extend the iron ore industrial chain, and achieve high-qual-
ity and optimized utilization of China’s iron ore.
Pilot-scale continuous and industrial-scale production
was carried out to further verify the preparation effect of
ultra-purity iron concentrate, which is shown in Figure 8.
Two cleaning stages were added to the reverse flotation
operation to make the flotation concentrate meet the
requirements of ultra-purity iron concentrate. The test
results show that the process can operate stably, and the
beneficiation indicators meet the desired quality standard
80 85 90 95
0.0
0.2
20
40
60
80
100
TFe grade TFe recovery SiO2 grade Acid insoluble matter
(a)
100 200 300
0.0
0.2
20
40
60
80
100
DJW-1 dosage (mg/L)
TFe grade TFe recovery
SiO2 grade Al2O3 grade Acid insoluble matter
(b)
Figure 6. Test results of (a) second-stage electromagnetic concentration, left, and (b) effect of DJW-1 dosage on impurity
removal from second-stage electromagnetic concentration concentrate
Table 8. Chemical composition analysis of flotation concentrates (%)
Composition Total Fe CaO MgO SiO
2 Al
2 O
3 S P K /(g/t)
Contents 71.88 0.024 0.008 0.30 0.15 0.0092 0.0020 0.0061
Composition Na TiO2 Mn Cu Pb Zn Acid Insoluble Matter
Contents 0.0072 0.032 0.005 0.0002 0.0012 0.0024 0.19
71.81 71.97 71.87 71.92
97.19 96.33 96.05 96.21
0.39 0.37 0.33 0.34 0.28 0.21 0.2 0.2
Grade/Recov
er(%)
y
71.81 71.88 72.28
93.58
70.71
51.75
0.35 0.3 0.3 0.15 0.15 0.14 0.19 0.19 0.18
Grade/Recov
er(%)
y