MODELING OF SINGLE FLOTATION COLUMN STAGES AND COLUMN CIRCUITS

A procedure for modelling single flotation columns and column circuits is described. In general terms, column models comprise three key components or expressions, to describe particle/bubble attachment, axial dispersion in the pulp zone, and net detachment in the froth zone. Previous models of these components are reviewed. In the current study, each column unit or stage is represented by a single zone model. Mineral recovery from each stage is related to a first order rate parameter and a residence time distribution. Based on experimental evidence and theory, an improved expression for the rate parameter is proposed. The model parameters are back-calculated from or fitted to experimental data. In this paper a number of model fitting examples are presented, these include single columns and column circuits. In the circuit examples, the mineral specific parameters are related to the properties of the feed, rather than to the operation of individual column stages. Consequently mineral behaviour is separated from column operation and circuit configuration. Mineral behaviour is related to particle size and an arbitrary floatability distribution. The relative merits of a number of floatability distributions are examined.