title: Experimental study of the mechanical stabilization of electric arc furnace dust using fluid cement mortars.
abstract: This article shows the results of an experimental study carried out in order to determine the maximum amount of electric arc furnace dust (EAFD) that can be incorporated into fluid cement-based mortars to produce mechanically stable monolithic blocks. The leaching performance of all mixes was studied in order to classify them according to the EU Council Decision 2003/33/EC. Two mortars were used as reference and three levels of EAFD incorporation were tested in each of the reference mortars. As the incorporation ratio of EAFD/cement increases, the mechanical strength decreases. This is due to the greater EAFD/cement and water/cement ratios, besides the presence of a double-hydrated hydroxide of Ca and Zn (CaZn2(OH)6·2H2O) instead of the portlandite phase (Ca(OH)2) in the mixes made with EAFD, as well as non-hydrated tricalcium silicate. A mass ratio of 2:1 (EAFD: cement-based mortar) can be added maintaining a stable mechanical strength. The mechanical stabilization process also reduced the leaching of metals, although it was not able to reduce the Pb concentration below the limit for hazardous waste. The high amount of EAFD mechanically stabilized in this experimental study can be useful to reduce the storage volume required in hazardous waste landfills.
authors.affiliation: Área de Mecánica de los Medios Continuos y Teoría de Estructuras, Universidad de Córdoba, España.
authors.forename: E F
authors.initials: EF
authors.lastname: Ledesma
authors.affiliation: Área de Ingeniería de la Construcción, Universidad de Córdoba, España. Electronic address: jrjimenez@uco.es.
authors.forename: J R
authors.initials: JR
authors.lastname: Jiménez
authors.affiliation: Área de Ingeniería de la Construcción, Universidad de Córdoba, España.
authors.forename: J
authors.initials: J
authors.lastname: Ayuso
authors.affiliation: Área de Química Inorgánica, Universidad de Córdoba España.
authors.forename: J M
authors.initials: JM
authors.lastname: Fernández
authors.affiliation: CERIS-ICIST, DECivil, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
authors.forename: J de
authors.initials: J
authors.lastname: Brito
keywords: Electric arc furnace dust; Hazardous waste; Leaching behaviour; Mechanical stabilization