Graphically Determined Column Péclet Number

In column testing of reactive solute transport, the retardation factor and column Péclet number can be simultaneously calculated by the nonlinear regression of the observed breakthrough curve. Several alternative methods exist to determine the retardation factor, but alternate techniques for determining the Péclet number have not been proposed. This paper presents a graphical method to obtain the Péclet number with examples of the proposed method. The graphical method provides results that are quite consistent with the nonlinear regression technique; and is a reasonable alternative, depending on the scatter in the effluent data.