Separation of KCl values from Canadian sylvinite and carnallite potash ores by selective flocculation

CIM Bulletin, Vol. 93, No. 1040, 2000

C. Poole and S.A. Beeson, Department of Mining and Mineral Engineering, University of Leeds, Leeds, United Kingdom

This paper reports on the development of selective flocculation processes for the direct recovery of KCl values from low-grade Canadian sylvinite and carnallite potash ores. Two reagent suites, consisting of either a non-selective cationic or selective non-ionic flocculant, together with the same selective anionic dispersant, were evaluated. Initial data from component mineral behaviour investigations, reagent adsorption studies and selective flocculation tests on a synthetic potash ore were used in the successful development of processes capable of recovering KCl values without the necessity for desliming to remove water-insolubles. Enhanced multi-stage treatment (involving redispersion and reflocculation) and subsequent floc recovery techniques (including sedimentation, hydrocyclones and froth flotation) were examined, and in all cases the influence of process parameters such as reagent dosages, conditioning times, solids concentration, particle size and other physical design criteria were investigated. The data reported clearly demonstrate the scale-up potential of these processes and possible
Keywords: Mineral processing, Flocculation processes, Selective flocculation processes, Sylvinite, Carnallite potash, Potash.