Global Characterization of Froth Speed Behavior in a Rougher Flotation Line

Flotation is one of the most complex processes in mining industry. In fact, non linear characteristics, large delays, significant disturbances and important unmeasurable variables make the process very difficult for automatic control. However, experimented operators are able to take adequate control actions based on superficial froth appearance. To ensure the obtaining of technical and economical benefits, it is necessary to identify different operational scenarios using quantitative information. In this work first we demonstrate, using step response analysis, that froth speed is closely related to pulp level. To model this relationship we propose a piecewise affine structure for froth speed-pulp level relation, yielding a hybrid model obtained applying hybrid identification techniques to real industrial data from a three bank rougher line. Results show that a non-linear relation exist between froth speed and pulp level, and the models obtained are able to describe flotation process dynamic.