Full characterization of granite waste sludge (GWS) was accomplished by X-ray diffraction (XRD) and Xray fluorescence (XRF) for identification of its phase and chemical composition. Different leaching tests were conducted to determine the efficiency of the GWS for metal stabilization in hazardous sludge. The leaching of the metals from stabilized contaminated sludge was decreased as the GWS amount increased. Only 15% of GWS was sufficient for stabilization of all metal ions under investigation. The main reason for metal immobilization was attributed to the aluminosilicates or silicates matrix within the GWS, which can transform the metals in the form of their insoluble hydroxides or absorbed in the stabilized matrix. Also, solidification/stabilization technique was used for remediation of contaminated sludge. Compressive strength test after curing for 28 days was used for measuring the effectiveness of remediation technique; it was found to be 1.88MPa. This indicated that the remediated sludge was well solidified and safe to be used as a raw substance for roadway blocks. Therefore, this huge amount of by-product sludge derived from the granite cutting industry, which has a negative environmental impact due to its disposal, can be utilized as a binder material for solidification/stabilization of hazardous sludge.
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