LEACHING TEST OF VITRIFIED FLY ASH AND CERAMIC SLAG FROM AN INCINERATOR OF MUNICIPAL SOLID WASTE (MSW) TREATED WITH Ca(OH)2 AT DIFFERENT CONCENTRATIONS AND MARLSTONE

Abstract

A public property site, situated over an alluvial terrace of the Idice Stream (Emilia Romagna Region-Italy) has been contaminated by a layer of waste, constituted by vitrified fly ashes and ceramic materials produced by an incinerator of municipal solid waste. The waste have high contents of heavy metals and exceed the Italian Law Limits of concentration for Cd, Cu, Pb and Zn (D. Lgs. 152/06, all. 5, tab.1). The in-situ remediation of the area was possible. In this study, alternative materials than the Portland cement has been tested for the environmental restoration and the further naturalization of the area. Leaching tests has been carried out treating the ashes with different concentrations of hydrated lime (CaOH2) and also with lime at 20% concentration and smectitic marlstone. At the end of the leaching test, most of the heavy metals in the waste has been immobilized by the lime/marlstone treatment