Flotation tests were performed on a sample of -30micron quartz in a batch flotation cell agitated by two differentimpellers and aerated with bubbles of various initial sizesgenerated by sintered glass discs. Prior to the flotationexperiments the system was carefully characterized in terms ofbubble size, power input and turbulence parameters includingturbulent energy spectra, turbulent fluctuating velocities andlocal rates of energy dissipation. Flotation rate constants weredetermined as a function of particle size for each of 32 differentexperimental conditions. The results confirmed the strongdependence of the flotation rate constant on particle size andbubble size. The results also indicated an optimum in theflotation rate constant as a function of particle size, bubble sizeand level of agitation. It is proposed that this optimum occurswhen the increased rate of collision/attachment due toturbulence in the cell space is matched by the increase in the rateof detachment due to turbulence in the impeller zone.
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