A kinetic model for the prediction of the performance of a froth flotation cell is proposed. The model is based on the assumption of a free-flowing concentrate froth. The flux of bubble surface is estimated from the cell aeration rate and the specific surface of the bubbles in the froth. The specific surface in the froth is based on the mean bubble size which is estimated by off-line image processing of photographs taken of the froth during laboratory scale batch tests. A sequence of batch flotation tests in which a low-rank UK coal was demineralized, by varying the initial addition of Sodium Dodecyl Sulphate (SDS), was used to test the consistency of the model predictions with experimental data. Although all the model parameters have a physical reality, not all were able to be measured at this stage. Nevertheless, the consistency of the predictions with the experimental data was encouraging, and the potential value of extended on-line image processing as a tool for improved experimentation was apparent.