Stabilization assessment of phenolic compounds from foundry sludge using additives

This work has been based on an industrial waste originated in an iron found ry activity. Because of its origin from the wet cleaning system of the gase s coming from the furnace, the waste contents in large amounts of water (60 %) makes its handling difficult. in a previous characterization of this was te a high ecotoxicity was experimentally obtained, taking the Spanish regul ation as reference. This toxicity was associated with a high leaching of he avy metals, basically zinc, and also with an organic contamination of the a queous Fraction, identified as phenolic compounds. In these cases, the use of specific additives for the phenolic compounds is strongly recommended. F ly ash, modified bentonite and lime were examined as additives in the stabi lization process. The use of lime produces the best benefits not only in th e ecotoxicity reduction but also in phenolic compounds retention in the sta bilized waste forms.