Stabilisation and solidification of steel industry sludge

摘要

This report presents the research done on the treatment of steel industry sludge by the solidification /stabilisation (S/S) process using desilicated fly ash (DFA) and lime as the binding agents. The sludge was characterized using X-ray fluorescence, X-ray diffraction, and geotechnical techniques. The main oxides in the sludge were iron oxide and zinc oxide. Unconfined compressed strength of 0.49 MPa was achieved with 40% DFA: lime (70:30) addition, at pH of 12.88. The leachability of Fe was reduced by 94% and Zn by 98.6%. The rate of lime consumption during stabilisation was best described with 2^nd order kinetics plot.