Assessing the Effect of Cone Ration, Feed Solids Concentration and Viscosity on Hydrocyclone Performance

In the mineral processing industry, comminution circuits contain slurries composed of a mixture of particles of varying degrees of liberation and size. Hydrocyclones are commonly used to classify these particles. If the classification stage is not efficient, both grinding and flotation cannot be optimised or operated efficiently. Ores that are mined in industry contain metals of varying specific gravity, which makes recovery of the desired metal challenging. This study focussed on the effect of the hydrocyclone spigot to vortex finder diameter ratio, termed as the cone ratio, solids concentration and viscosity on the classification of two dual density ores. The rheological characteristic of the overflow was also evaluated. A UG2 ore (Upper Group), which consists mainly of silicates, and chromite, and an iron ore, containing mainly iron and silicates, were used as feed material. The UG2 test work was carried out on a University of Cape Town (UCT) 4 inch Multotec cyclone, while the iron ore test work was carried out on an Anglo-American 4 inch Krebs cyclone. The cyclone performance was assessed using the corrected cut size, water recovery to the underflow, sharpness of separation and feed throughput. The results indicate the significant impact of the cone ratio, feed solids concentration, and viscosity on hydrocyclone performance.