2058 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
same time, the ash content of the material after rod milling
decreases with the decrease of particle size, and the ash con-
tent of –0.045 mm particle size decreases the most, from
14.81 to 8.62%.
With the increase of rod milling time, the intermediate
density material was dissociated from vitrinite and miner-
als, and were allocated to the products of low density and
high density level respectively. When the grinding time is
10 min, the difference of yield and ash of the two density
levels of –1.35 and +1.40g/cm3are larger, which is con-
ducive to the enrichment of macerals. Thevitrinite is eas-
ily enriched in the low density level, and the content of
–1.35g/cm3vitrinite is the highest when the milling time
is 10 min.
The results of Box-behnken orthogonal test show that
the rotational frequency has more significant effect on RV
and EV. The mean value of RV and EV obtained from the
optimal test conditions are 71.61% and 1.15, which can
well realize the low-cost, low-pollution and high-efficiency
enrichment of low-rank bituminous coal macerals.
DISCLOSURE STATEMENT
No potential conflict of interest was reported by the
author(s).
FUNDING
This work was supported by the National Natural Science
Foundation of China under Grant No. 51874303.
REFERENCES
Chang, J., Z. Li, Y. Fu, C. Yang, W. Song, and Z. Zhu.
2021. Upgrading and quality-classification of iner-
tinite-rich coal from Western China based on mac-
eral separation. Powder Technology 382:48–59. doi:
10.1016/j.powtec.2020.12.047.
Das, A., and B. Sarkar. 2018. Advanced Gravity
Concentration of Fine Particles: A Review. Mineral
Processing and Extractive Metallurgy Review 39(6):
359–394. doi: 10.1080/08827508.2018.1433176.
Duan, C., X. Wen, C. Shi, Y. Zhao, B. Wen, and Y. He.
2009. Recovery of metals from waste printed circuit
boards by a mechanical method using a water medium.
Journal of Hazardous Materials 166 (1): 478–82. doi:
10.1016/j.jhazmat.2008.11.060.
Ge, L., H. Feng, C. Xu, Y. Zhang, and Z. Wang. 2018.
Effect of hydrothermal dewatering on the pyroly-
sis characteristics of Chinese low-rank coals. Applied
Thermal Engineering 141:70–78. doi: 10.1016
/j.applthermaleng.2018.05.098.
Figure 12. Response surfaces of RV and EV under different combinations of two parameters
Table 8. Results of confirmatory test
No. F(Hz) P(MPa) V(ml/s) RV(%) EV
1 30.00 0.03 15.00 71.59 1.14
2 30.00 0.03 15.00 72.03 1.12
3 30.00 0.03 15.00 71.22 1.18
Mean value 71.61 1.15
Projected value 71.30 1.17
same time, the ash content of the material after rod milling
decreases with the decrease of particle size, and the ash con-
tent of –0.045 mm particle size decreases the most, from
14.81 to 8.62%.
With the increase of rod milling time, the intermediate
density material was dissociated from vitrinite and miner-
als, and were allocated to the products of low density and
high density level respectively. When the grinding time is
10 min, the difference of yield and ash of the two density
levels of –1.35 and +1.40g/cm3are larger, which is con-
ducive to the enrichment of macerals. Thevitrinite is eas-
ily enriched in the low density level, and the content of
–1.35g/cm3vitrinite is the highest when the milling time
is 10 min.
The results of Box-behnken orthogonal test show that
the rotational frequency has more significant effect on RV
and EV. The mean value of RV and EV obtained from the
optimal test conditions are 71.61% and 1.15, which can
well realize the low-cost, low-pollution and high-efficiency
enrichment of low-rank bituminous coal macerals.
DISCLOSURE STATEMENT
No potential conflict of interest was reported by the
author(s).
FUNDING
This work was supported by the National Natural Science
Foundation of China under Grant No. 51874303.
REFERENCES
Chang, J., Z. Li, Y. Fu, C. Yang, W. Song, and Z. Zhu.
2021. Upgrading and quality-classification of iner-
tinite-rich coal from Western China based on mac-
eral separation. Powder Technology 382:48–59. doi:
10.1016/j.powtec.2020.12.047.
Das, A., and B. Sarkar. 2018. Advanced Gravity
Concentration of Fine Particles: A Review. Mineral
Processing and Extractive Metallurgy Review 39(6):
359–394. doi: 10.1080/08827508.2018.1433176.
Duan, C., X. Wen, C. Shi, Y. Zhao, B. Wen, and Y. He.
2009. Recovery of metals from waste printed circuit
boards by a mechanical method using a water medium.
Journal of Hazardous Materials 166 (1): 478–82. doi:
10.1016/j.jhazmat.2008.11.060.
Ge, L., H. Feng, C. Xu, Y. Zhang, and Z. Wang. 2018.
Effect of hydrothermal dewatering on the pyroly-
sis characteristics of Chinese low-rank coals. Applied
Thermal Engineering 141:70–78. doi: 10.1016
/j.applthermaleng.2018.05.098.
Figure 12. Response surfaces of RV and EV under different combinations of two parameters
Table 8. Results of confirmatory test
No. F(Hz) P(MPa) V(ml/s) RV(%) EV
1 30.00 0.03 15.00 71.59 1.14
2 30.00 0.03 15.00 72.03 1.12
3 30.00 0.03 15.00 71.22 1.18
Mean value 71.61 1.15
Projected value 71.30 1.17