Evaluation of usefulness of hydrated lime in process of stabilization of sludges from electrocoating

The effect of hydrated lime on the course of neutralization of sludges from electrocoating (GS) is determined. For our experiment two solidifying-binding mixtures (13) were prepared: B1 and B2. The mixture B1 was the combination of Portland cement, hydrated lime, mortar sand and fly ashes from hard coal burning used in various proportions. From the matrix of the second mixture, 132, hydrated lime was removed; instead a double dose of mortar sand was applied. In both mixtures, the content of Portland cement CEM I 32.5R did not exceed 40% of their entire mass. In the stabilizers obtained, galvanic sludges constituted 75 to 87.5% of their mass. The efficiency of the process of toxic pollutants immobilization was assessed after 28 days of sludge maturation. Monolithic structures of stabilized sludge were subjected to the tests of mechanical axial compression strength and to the tests of heavy metals leaching, according to the standard PN-EN 12457-4: 2006 [1].