Dynamic and Geometrical Models to Estimate the Density of Fully-Loaded Bubbles in the Column Flotation of Silica Sand

ABSTRACT

This paper presents a comparison between the density of the bubble-particle aggregate pertinent to column flotation of mineral particles estimated with two models: one resulting from a balance of the forces acting on the aggregate that rises in a quiescent aqueous solution (termed dynamic or hydrodynamic model), and the other, of geometrical nature, which consists in accommodating the particles of known density, morphology and size distribution on the surface of an spherical bubble of known diameter. To compare the performance of the models, knowledge of terminal velocity (Vt), diameter (dbp) and friction coefficient (Cd) of the aggregate is required, as well as the size distribution of particles adhered to the bubbles, in order to determine the density of the aggregate (ρbp). It is concluded that the geometrical model is able of approximating the estimations of the dynamic model, and may be therefore used to preliminary estimate the maximum density that a bubble-particle aggregate may reach.