THE INFLUENCE OF BUBBLE-SIZE ON SCALE-UP OF COLUMN FLOTATION CELLS

Classical reactor design theory, incorporating the use of the axial di spersion model and assuming flotation to be a first order process, is shown to be adequate in predicting the performance of a large column u sing a rate constant determined in a small column as long as due consi deration is given to any difference in bubble sizes in the two cells. If the bubble sizes in the two columns are not the same it is proposed that the proper value of the rate constant to be used for the large c olumn is found by using the relationship k infinity d(b)(-1.5). The ve ssel dispersion number, D/uL, is accurately predicted using published relationships. The small column rate constant should preferably be det ermined under conditions in which the froth zone recovery is 100%; A f roth zone recovery in the large column of25% was found to be applicabl e for the present scale-up calculation procedure.