A comprehensive review of dense medium cyclone technology for coal preparation

Dense medium cyclone (DMC) is the most efficient, mature and universally accepted coal preparation technology known at present. Since its invention, extensive efforts have been made to understand its working mechanism and to study the effects of various parameters on its performance. The emergence of recent knowledge through experimental and simulation work has improved the understanding of the influence of feed characteristics, design and operating variables and medium characteristics upon dense medium cyclone performance. Trend toward larger diameter cyclones has enhanced its application to a wider size range and greater tonnages. The development of the three product cyclone also caused an uplift to its acceptance to the processing of coal of varying quality. Moreover, efforts have been made to commercially utilize dense medium cyclone technology for fine coal separation. This paper summarizes the developments and knowledge about dense medium cyclone technology for its application in coal preparation. Aspects reviewed include the process mechanism, design variations, influence of process variables on performance, and application to fine coal separation.