Thickeners versus centrifuges – a coal tailings technical comparison

Abstract

Both high-rate thickeners and dewatering centrifuges are used in the application of dewatering coal tailings. Both applications are well advanced and accepted as means to dewater coal. This paper compares a high-rate thickener to a solid bowl centrifuge with respect to numerous process, mechanical, electrical, control, layout and operator variables. Process variables include feed, effluent water discharge, retention time, and centrifuge cake moisture/thickener underflow percent solids. A comparison of a 33 m diameter thickener and a 1.117 m diameter solid bowl centrifuge with respect to g square meters is shared. The suitability of the dewatering application is governed by the properties of the resultant solids mixture. Different ash tailings, particularly those containing clay, presented a challenge to both the operations of the thickener and the centrifuge. A holistic view to the entire process is required.