METAL SEDIMENT INTERACTION DURING RESUSPENSION

A calibrated shaker was used to resuspend sediments from Hamilton Harbour, Ontario at different shear stresses. The flocs formed by resuspension were irreversible and increased in size and number with increasing shear. Individual particle size was constant at about 0.1 mum for the different flocs and independent of shear, but agglomeration size increased with shear. H-ion exchange as a function of sediment concentration fits a Langmuir type function well. Exchange of total Ba, Ca, Cd, Cr, Cu, Mg, Ni, Pb and Zn with H+ were determined for the different shear regimes which covered quiescence to gale conditions. A simple lumped one intrinsic constant and fixed capacitance electrostatic model is used to fit the exchange data for each divalent metal.