Pilot scale filter testwork on various concentrate and cobalt plant streams was conducted in the mid 1990s. Ceramic filters were selected for use on copper concentrates at Nkana and Mufulira Concentrators. This was based on the assumption that thermal dryers would be eliminated from the dewatering circuits thus lowering operating costs significantly. A review of their performance and future plans is considered in the context of expanding production requirements. (c) 2005 Elsevier Ltd. All rights reserved.