Abstract
Microwave heating through materials' dielectric loss endows energy saving and consumption reduction and production clean characteristics. Pilot-scale study was initiated to evaluate the enhanced effect of microwave heating on carbothermal reduction process of pyrolusite. Results indicated that carbothermal reduction process for low-grade pyrolusite was divided into three stages identified by temperatures: <145 °C, 145 °C–400 °C, >400 °C. Meanwhile, ƞMn value of 95.38% can achieve at 650 °C for 60 min with 15% coal addition, with low Fe2+ content, indicating efficient pyrolusite reduction by microwave heating. Moreover, MnO2 peaks disappeared and MnO peaks were detected and product surface became loose and porous with numerous cracks and holes, meanwhile grain shape became more regular with a smaller particle size after further microwave treatment. The study highlights that the non-conventional technology by microwave heating to reduce low-grade pyrolusite is very promising and could be considered for full scale applications.
Original language | English (US) |
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Pages (from-to) | 846-854 |
Number of pages | 9 |
Journal | Powder Technology |
Volume | 360 |
DOIs | |
State | Published - Jan 15 2020 |
Bibliographical note
Funding Information:Financial supports from the National Natural Science Foundation of China (No: U1802255), the Key Projects in the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (No. 2015BAB17B00), the Hunan Provincial Science and Technology Plan Project, China (No. 2016TP1007), and Innovative Research Team (in Science and Technology) in University of Yunnan Province were sincerely acknowledged.
Funding Information:
Financial supports from the National Natural Science Foundation of China (No: U1802255 ), the Key Projects in the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period (No. 2015BAB17B00 ), the Hunan Provincial Science and Technology Plan Project , China (No. 2016TP1007 ), and Innovative Research Team (in Science and Technology) in University of Yunnan Province were sincerely acknowledged. Appendix A
Publisher Copyright:
© 2019 Elsevier B.V.
Keywords
- Enhanced carbothermal reduction
- Low-grade pyrolusite
- Microwave heating
- Pilot-scale