title: Pilot-scale road subbase made with granular material formulated with MSWI bottom ash and stabilized APC fly ash: environmental impact assessment.
abstract: A granular material (GM) to be used as road sub-base was formulated using 80% of weathered bottom ash (WBA) and 20% of mortar. The mortar was prepared separately and consisted in 50% APC and 50% of Portland cement. A pilot-scale study was carried on by constructing three roads in order to environmentally evaluate the performance of GM in a real scenario. By comparing the field results with those of the column experiments, the overestimations observed at laboratory scale can be explained by the potential mechanisms in which water enters into the road body and the pH of the media. An exception was observed in the case of Cu, whose concentration release at the test road was higher. The long-time of exposure at atmospheric conditions might have favoured oxidation of organic matter and therefore the leaching of this element. The results obtained showed that immobilization of all heavy metals and metalloids from APC is achieved by the pozzolanic effect of the cement mortar. This is, to the knowledge of the authors, the only pilot scale study that is considering reutilization of APC as a safe way to disposal.
authors.affiliation: Department of Materials Science and Metallurgical Engineering, University of Barcelona (UB), Martí i Franquès, 1, E-08028 Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: del Valle-Zermeño
authors.affiliation: Department of Architectural Technology II, Polytechnic University of Catalonia (UPC), Ave. Dr. Marañón 44, E-08028 Barcelona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Formosa
authors.affiliation: Valorización de Escorias para la Construcción S.A. (VECSA), Tarragona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Prieto
authors.affiliation: Servei d'Incineració de Residus Urbans S.A. (SIRUSA), Tarragona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Nadal
authors.affiliation: Department of Materials Science and Metallurgical Engineering, University of Barcelona (UB), Martí i Franquès, 1, E-08028 Barcelona, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Niubó
authors.affiliation: Department of Materials Science and Metallurgical Engineering, University of Barcelona (UB), Martí i Franquès, 1, E-08028 Barcelona, Spain. Electronic address: chimenos@ub.edu.
authors.forename: J M
authors.initials: JM
authors.lastname: Chimenos
mesh_terms: D001151:Arsenic / Q000032:analysis; D060729:Coal Ash; D019245:Compressive Strength; D003252:Construction Materials; D004777:Environment; D017745:Incineration; D007220:Industrial Waste; D008670:Metals / Q000032:analysis; D010316:Particle Size; D010865:Pilot Projects
chemical_list: D060729:Coal Ash; D007220:Industrial Waste; D008670:Metals; D001151:Arsenic
keywords: APC residues; Field scale road; Granular material; Leaching study; MSWI bottom ash