Application of method of temporal moments to the contaminant exit breakthrough curves from rockfill media

In this research tried to examine the transport and dispersion characteristics of rockfill media with application of the two completely flowthrough discharges, two media diameters and five injection masses. Firstly by means of a digital EC sensors and related data logger system and software, the experimental BC curves have been extracted and then by application of method of temporal moments, the longitudinal dispersion coefficient and other parameters like mean residence time, variance and coefficient of skewness have been computed. Afterwards, by using analytical solution of classical advection dispersion equation and extracted coefficients from method of moments, the theoretical BC curves have been calculated and were compared with experimental ones. The applicability of method of moments have been approved by the results and also concluded that (except the climax point, in some cases) the theoretical solution can cover all regions of experimental BC curve.