Title: Potential of Blast Furnace Slags to Immobilize Toxic Wastes

Author(s): A. Macias, S. Goiii, J. Madrid, J.M. Diez and E. del Castillo

Publication: Symposium Paper

Volume: 178

Issue:

Appears on pages(s): 893-910

Keywords: blast furnace slag; cement; stabilization; wastes.

DOI: 10.14359/6014

Date: 6/1/1998

Abstract:
Waste disposal has become a major concern in most industrial countries because of limited sites and strict environmental standards for landfilling. The common cementing material, widely available and used, are normal portland cement, lime and high-calcium fly ashes from coal combustion. Ground granulated blast-furnace slag is also a component in binder formulation of general interest because of its potential for metal immobilization, based on its physical and chemical properties. The present work analyses the immobilization of toxic wastes containing Cd, Pb and Cr in portland cement matrices with 80 % of blast-finnace slag in comparison with plain portland cement matrices. The results show that lower levels of toxic ions in pore solution are obtained for blast-&mace blended cements due to differences in phases formed and the reduction of species to less toxic ones that occurs at the redox potential of slags. Differences in porosity also cause a reduction in metal leaching from slag-blended cements.