XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 2051
the backwash water and the centrifugal force, and the low-
density material flows out of the rotor with the overflow,
and the formation of the concentrate product.
Evaluation Indicators
In order to characterise the degree of dissociation, quan-
titative analysis of the macerals is required with the aid of
a polarised light microscope and reference to the national
standard GB/T8899-2013. Since both vitriniteand exinite
belong to the active components in the coal liquefaction
process, they were grouped together for analysis. Therefore,
the mass fraction content V of the vitrinite, the recovery
rate ηv of the vitrinite, and the enrichment ratio Ev of the
vitrinite were used to evaluate the effect of dissociation and
enrichment of the macerals (Zhang et al., 2019).
V0
V
100%
V
1 1 #
#h
c
=(1)
E V
V1
V
0
=(2)
In the above equation: V1 is the mass fraction content of
vitrinite in the product, %γ1 is the yield of vitrinite in the
product, %V0 is the mass fraction content of vitrinite in
the feed, %.
RESULTS AND DISCUSSION
Grinding
Size Analysis
The amount of each feed was set to 100g, the grinding
time was set as a variable, which was controlled to be 5,
10, 15, 20, and 30 min, respectively.From Figure 5a, it
can be seen that the particle size of the coal samples after
grinding becomes smaller, and all of them are distrib-
uted below 0.5 mm.The yield of the three particle sizes of
0.125–0.074, 0.074–0.045, and –0.045 mm increase with
the increase of grinding time, while the yield of the particle
Figure 2. The infrared spectra of low-rank coal macerals
Figure 3. KJXMB-3 three-roller four-cylinder rod mill
the backwash water and the centrifugal force, and the low-
density material flows out of the rotor with the overflow,
and the formation of the concentrate product.
Evaluation Indicators
In order to characterise the degree of dissociation, quan-
titative analysis of the macerals is required with the aid of
a polarised light microscope and reference to the national
standard GB/T8899-2013. Since both vitriniteand exinite
belong to the active components in the coal liquefaction
process, they were grouped together for analysis. Therefore,
the mass fraction content V of the vitrinite, the recovery
rate ηv of the vitrinite, and the enrichment ratio Ev of the
vitrinite were used to evaluate the effect of dissociation and
enrichment of the macerals (Zhang et al., 2019).
V0
V
100%
V
1 1 #
#h
c
=(1)
E V
V1
V
0
=(2)
In the above equation: V1 is the mass fraction content of
vitrinite in the product, %γ1 is the yield of vitrinite in the
product, %V0 is the mass fraction content of vitrinite in
the feed, %.
RESULTS AND DISCUSSION
Grinding
Size Analysis
The amount of each feed was set to 100g, the grinding
time was set as a variable, which was controlled to be 5,
10, 15, 20, and 30 min, respectively.From Figure 5a, it
can be seen that the particle size of the coal samples after
grinding becomes smaller, and all of them are distrib-
uted below 0.5 mm.The yield of the three particle sizes of
0.125–0.074, 0.074–0.045, and –0.045 mm increase with
the increase of grinding time, while the yield of the particle
Figure 2. The infrared spectra of low-rank coal macerals
Figure 3. KJXMB-3 three-roller four-cylinder rod mill