Solidification and stabilization of Pb, Zn, Cd and Cu in tailing wastes using cement and fly ash

Three types of acidic solution (0.1 N HCl, HNO3HClO4 and HNO3HCl) were applied to determine the elemental compositions for tailing wastes and fly ash. In addition, a sequential extraction was carried out to determine the chemical partitioning. The curing period of the solidified/stabilized (S/S) materials was estimated for its unconfined compressive strength (UCS) at three, seven and 28 days in order to learn the mixing ratio of cement, tailing wastes and fly ash, respectively. To obtain the highest strength, the optimum mixing ratio was considered to be 85% tailing wastes and 10% fly ash (TW5FA10).