For column scale-up, two parameters must be known: mineral rate constant and solids vessel dispersion number. Rate constants for all minerals can be measured from two modes of column operation, i.e., batch and continuous. Vessel dispersion number of solids particles can be readily predicted using available correlations and is related to column size, particle size and operating conditions. Rate constants measured from the two modes of column operation are described and compared. It was found that the rate constant obtained from batch column was less than that obtained from continuous operation. The impact of this difference upon column scaleup is investigated.