Simultaneous determination of collection zone rate constant and froth zone recovery in a mechanical flotation environment

This paper presents the results of an investigation in which the new JKMRC Flotation Cell was used to determine the collection zone rate constant and froth zone recovery of a copper rougher ore simultaneously.The determination of these two parameters has been based on the straight line relationship that exists between the overall flotation rate constant and the froth depth 1].Experimental work was conducted using a copper rougher ore with a P₈₀ of 200 μm. Operating variables such as air flow rate, impeller speed, feed percent solids, collector and frother dose, and wash water flow rate were investigated. Analysis for copper and iron minerals (chalcopyrite and pyrite, respectively) was carried out.The results indicate that the collection zone rate constant of both copper and iron minerals increased with increasing air flow. Froth zone recovery, on the other hand, decreased as air flow was increased, possibly as a result of increased detachment of particles from bubbles in the froth. Increasing the impeller speed also increased collection zone rate constant and decreased the froth zone recovery of both minerals.Experiments at different wash water flow rates have showed that events occurring in the froth zone do not affect the kinetics of the pulp zone. Moreover, and interestingly, the froth recovery of attached particles (wash water reduced entrainment to a minimum) was non-selective. The froth recovery curves for chalcopyrite and pyrite followed each other very closely in every instance studied.The work has proved that it is possible to measure both the collection zone rate constant and froth zone recovery simultaneously and continuously in a mechanical flotation environment. The results obtained to date are interesting and the work is continuing.