THE ESSENTIAL DIFFERENCE BETWEEN THE TWO OPTIMUM PROPORTIONS FLOCCULATION RATIOS.

The fact that the optimum proportion flocculation ratio is different when determined by the alpha (Dean and Webb) and beta (Ramon) procedures is pointed out. It is demonstrated that this difference is a consequence of the difference in the two methods, and that the two optima, though they may in certain cases lie near together, can never coincide. A new ratio (the epsilon ratio), intermediate between the alpha and beta ratios, and having theoretical advantages over both of them, is defined.