3614 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
product is +15–60 mm, which can be sold as a raw material
for concrete aggregate after particle size adjustment.
Dense Media Separation Tests
Due to equipment limitations, XRT sorting equipment has
low separation efficiency for fine particles. In order to fur-
ther improve the yield of dolomite product and taking into
account the significant density difference between Pb-Zn
minerals, barite and dolomite, a dense media separation
method was introduced as the second-stage tailings rejec-
tion step.
DMS takes place in a fluid media with a density
between that of the light and heavy fractions that are to be
separated. The separation is dependent upon density and
particle shape. Inside the cyclone, the specific gravity of the
suspension varies in different areas, and overall, there is a
trend of increasing specific gravity radially from inside to
outside and axially from top to bottom (Chu and Chen
et al., 2016 Chen and Chu et al., 2017 Napier-Munn,
2018). Mineral particles pass through different areas during
their movement and those with a density lower than the
suspension density in that area move upwards and inwards,
while those with a density higher than suspension density
move outwards and downwards. Finally, light particles are
discharged from the overflow port, while heavy products
are discharged from the underflow port.
Tests for different density were conducted in order to
determine the appropriate suspension density, as shown in
Figure 2.
Figure 2 indicates that the light product (dolomite)
yield increases with the increase of the suspension density,
with an increased loss of lead and zinc. By evaluating the
test results, the suspension density was determined as
2.47 g/mL. All the ore samples were treated by dense
medium cyclone at suspension density of 2.47 g/mL. The
results are shown in Table 3.
Dolomite product produced using a dense cyclone gen-
erated a yield of 38%, while containing 0.06% Pb and
0.38%. Dolomite product yield from the DMS test was
23.52%. This helped to reduce the tailings yield. The Pb
and Zn losses were 1.68% and 2.51% respectively.
FLOTATION TESTS
After two stages of dolomite rejection by XRT sorting and
dense medium separation, the feed grade of flotation test
material increased significantly, Flotation tests were con-
ducted to obtain the optimum dosage for the flotation
reagents.
Table 3. Test results of dense medium cyclone (sample
preparation for subsequent tests)
Product
Name
Operation
Yield, %
Grade, %
Operation
Recovery, %
Pb Zn Pb Zn
Cyclone
concentrate
62.00 1.88 7.88 98.08 97.13
Dolomite
product
38.00 0.06 0.38 1.92 2.87
Feed 100.00 1.19 5.03 100.00 100.00
2.25 2.30 2.35 2.40 2.45 2.50 2.55 2.60 2.65
20
25
30
35
40
45 Light product yield
Recovery of Pb
Recovery of Zn
Suspension Density(g/mL)
0
2
4
6
8
10
Figure 2. Density test results of suspension in dense medium cyclone
Li
t
Product
Yield(%)
Pb&Zn
Recovery(%)
product is +15–60 mm, which can be sold as a raw material
for concrete aggregate after particle size adjustment.
Dense Media Separation Tests
Due to equipment limitations, XRT sorting equipment has
low separation efficiency for fine particles. In order to fur-
ther improve the yield of dolomite product and taking into
account the significant density difference between Pb-Zn
minerals, barite and dolomite, a dense media separation
method was introduced as the second-stage tailings rejec-
tion step.
DMS takes place in a fluid media with a density
between that of the light and heavy fractions that are to be
separated. The separation is dependent upon density and
particle shape. Inside the cyclone, the specific gravity of the
suspension varies in different areas, and overall, there is a
trend of increasing specific gravity radially from inside to
outside and axially from top to bottom (Chu and Chen
et al., 2016 Chen and Chu et al., 2017 Napier-Munn,
2018). Mineral particles pass through different areas during
their movement and those with a density lower than the
suspension density in that area move upwards and inwards,
while those with a density higher than suspension density
move outwards and downwards. Finally, light particles are
discharged from the overflow port, while heavy products
are discharged from the underflow port.
Tests for different density were conducted in order to
determine the appropriate suspension density, as shown in
Figure 2.
Figure 2 indicates that the light product (dolomite)
yield increases with the increase of the suspension density,
with an increased loss of lead and zinc. By evaluating the
test results, the suspension density was determined as
2.47 g/mL. All the ore samples were treated by dense
medium cyclone at suspension density of 2.47 g/mL. The
results are shown in Table 3.
Dolomite product produced using a dense cyclone gen-
erated a yield of 38%, while containing 0.06% Pb and
0.38%. Dolomite product yield from the DMS test was
23.52%. This helped to reduce the tailings yield. The Pb
and Zn losses were 1.68% and 2.51% respectively.
FLOTATION TESTS
After two stages of dolomite rejection by XRT sorting and
dense medium separation, the feed grade of flotation test
material increased significantly, Flotation tests were con-
ducted to obtain the optimum dosage for the flotation
reagents.
Table 3. Test results of dense medium cyclone (sample
preparation for subsequent tests)
Product
Name
Operation
Yield, %
Grade, %
Operation
Recovery, %
Pb Zn Pb Zn
Cyclone
concentrate
62.00 1.88 7.88 98.08 97.13
Dolomite
product
38.00 0.06 0.38 1.92 2.87
Feed 100.00 1.19 5.03 100.00 100.00
2.25 2.30 2.35 2.40 2.45 2.50 2.55 2.60 2.65
20
25
30
35
40
45 Light product yield
Recovery of Pb
Recovery of Zn
Suspension Density(g/mL)
0
2
4
6
8
10
Figure 2. Density test results of suspension in dense medium cyclone
Li
t
Product
Yield(%)
Pb&Zn
Recovery(%)