Sludge disposal in coastal waters - desorption of heavy metals from sewage sludge in seawater

A basic prerequisite for the mathematical simulation of the physical dispersal of sewage sludge in coastal waters is the knowledge of the rate of desorption of heavy metals from the sludge, and the partition between the dissolved and adsorbed states in equilibrium conditions. Results of experiments, carried out by Rohatgi and Chen (1975) on the desorption of heavy metals from digested sewage sludge particles after dilution by seawater over a period of 36 days, were analysed to determine the equilibrium partition coefficients and desorption rate constants for cadmium, zinc, copper, nickel, manganese and lead. The conditions in the early stages if the experiments are considered to approximate to conditions at sludge disposal sites in UK waters