Prediction of complex sulfide flotation performances by a combined 3D fractal and colour analysis of the froths

It has long been accepted that both appearance is a good qualitative indica tor of the performance of the flotation process. This paper investigates th e possibility of a froth surface 3D reconstruction that can provide signifi cant information about the process efficiency. The froth 3D model was reali sed performing a preliminary watershed segmentation of the image, a further morphological and morphometrical analysis and finally building a series of "domes" founded on the equivalent ellipses of the identified bubbles. Heig ht and curvature of the resulting ellipsoids were defined analysing light i ntensity distribution inside each identified domain (bubble). The technique developed generates an elevation model of the surface that is then analyse d by a fractal method. The froth surface showed two fractal dimensions that can be used, along with froth colour parameters, to forecast mineral grade s of the froths. (C) 2000 Published by Elsevier Science Ltd. All rights res erved.