Comparison of the Flotation Performance between Wide and Narrow Particle Size Ranges of Coal

Abstract

The flotation completion degree τ and an energy parameter E were proposed to compare the flotation effect for wide and narrow particle size ranges. Flotation rate tests were conducted at different agitation speeds in a laboratory flotation cell on different particle-sized coal. The results showed that the particle constitution of the sample was unimodal and that the yields of the middle particle size (−250 µm to +75 µm) and middle density (1.40 g/cm³ to 1.60 g/cm³) were high. Optimal flotation recovery for the various sizes occurred at the lower speeds (1500 rpm or 1800 rpm). During flotation, the τ value initially increased and then decreased. Compared with the narrow particle size, the wide particle size exhibited a better flotation effect, less ash in clean coal, and higher recovery.

Keywords:

• Agitation speed
• Comparison
• Flotation
• Particle size
• Power

Acknowledgments

The authors would like to thank the “National Key Basic Research Program of China” (Grant No. 2012CB214905) and the Innovation Foundation of CUMTB for PhD Graduates (Grant No. 800015Z633) for their support.