A new small-scale test to determine flotation performance – Part 1: Overall performance

• We present a new small-scale test for evaluating flotation separability.
• The test is sensitive to key particle attributes known to influence separation.
• The results are comparable to batch and plant data.
• The test has potential to complement the floatability component approach.

The majority of flotation models incorporate a parameter that describes the propensity of particles or classes of particles to be recovered through true flotation. This is typically captured in the flotation rate constant or “floatability”, and results from complex interactions between particles, solid/liquid/air interfaces and operational variables.Historically, there have been two distinct approaches in determining flotation rate parameters for industrial circuits. Fundamental approaches have focused on mechanisms for quantifying particle–bubble interactions and how these relate to kinetics. The more applied approach, which uses floatability components (grouping of particles that have the same flotation behaviour in terms of rate of recovery), relies on the availability of plant and batch test data, as well as specialised equipment measurements, to back-calculate floatability components or rate parameters, and their distribution in the feed. Since the parameters are derived from experimental data they are only applicable under the specific operating and feed conditions from which they are derived.A third method is emerging which applies mineralogical data to determine the flotation response of individual particles. This is done typically through a Cassie-type approach if the rates of the liberated components are known, or by developing a database of information which relates the flotation response of classes of particles to key mineralogical features.In this paper, a new small-scale test is presented, to compliment current laboratory batch test methods for separability characterisation. Data are presented to demonstrate the comparability of the overall separation achieved in the small-scale test to batch flotation and full scale plant measurements. The small-scale test is shown to be sufficiently sensitive to particle surface attributes, and based on the results presented in this paper, is a good candidate for further development to potentially determining flotation rate parameters. Work in this area is ongoing and will be reported in a subsequent article.