Abstract
Froth flotation is now the most commonly used method for cleaning fine-coal fractions in coal-preparation plants. Past research and industrial practice have demonstrated that froth flotation achieves excellent separation efficiencies for fine coals having only a small fraction of middling particles. However, the efficiency of froth flotation decreases sharply as the concentration of middling particles increases. This is due to the flotation of high-ash particles that have a small amount of hydrophobic coal present at the surface. Because gravity-based processes are much more efficient for the treatment of middlings, the application of centrifugal washing for fine-coal cleaning was studied with an emphasis on the primary cleaning of fine-circuit feed. Results are shown of a parametric study that used a semibatch Falcon centrifugal concentrator. The results of the study revealed that separation performance is a function of particle size, bowl geometry, feed solids content and feed rate.
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SME Preprint 94–259, SME Annual Meeting, Feb. 14–17, 1994, Albuquerque, NM.
M&MP Paper 94–611. Discussion of this peer-reviewed and approved paper is invited and must be submitted, in duplicate, prior to Aug. 31, 1995.
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Honaker, R.Q., Paul, B.C., Wang, D. et al. Application of centrifugal washing for fine-coal cleaning. Mining, Metallurgy & Exploration 12, 80–84 (1995). https://doi.org/10.1007/BF03403082
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DOI: https://doi.org/10.1007/BF03403082