title: Long-term environmental impacts of building composites containing waste materials: Evaluation of the leaching protocols.
abstract: The NEN 7375 test has been proposed for evaluating the long-term environmental impacts caused by the release of contaminants from monolithic building and waste materials. Over a period of 64days, at specific points in time, the leaching solution (demineralised water) is replenished. By applying the NEN 7375 test, leaching of contaminants that is based mainly on diffusion is followed. In the present work, the results from modified leaching protocols were evaluated against those obtained by NEN 7375 test. In modified protocols, synthetic sea, surface and MilliQ water were used for the leaching of selected elements and chromate, molybdate and vanadate from compact and ground building composites (98% mixture of fly ash (80%) and cement (20%), and 2% of electric arc furnace (EAF) dust) over 6months. The leaching solutions were not replenished, imitating both the diffusion and the dissolution of contaminants. The data revealed larger extent of leaching when the leaching solution was not replenished. More extensive was also leaching from ground composites, which simulated the disintegration of the material over time. The composition of the leaching solution influenced the release of the matrix constituents from the composites and, consequently, the amount of elements and their chemical species. Synthetic sea and surface water used as leaching solutions, without replenishing, were found to be suitable to simulate the conditions when the building material is immersed in stagnant environmental waters.
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia.
authors.forename: Ana
authors.initials: A
authors.lastname: Drinčić
authors.affiliation: University of Montenegro, Faculty of Metallurgy and Technology, Džordža Vašingtona bb, 81000 Podgorica, Montenegro.
authors.forename: Irena
authors.initials: I
authors.lastname: Nikolić
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
authors.forename: Tea
authors.initials: T
authors.lastname: Zuliani
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia.
authors.forename: Radmila
authors.initials: R
authors.lastname: Milačič
authors.affiliation: Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia; Jožef Stefan International Postgraduate School, Jamova 39, 1000 Ljubljana, Slovenia. Electronic address: janez.scancar@ijs.si.
authors.forename: Janez
authors.initials: J
authors.lastname: Ščančar
mesh_terms: D060729:Coal Ash / Q000032:analysis; D003252:Construction Materials; D004058:Diffusion; D004391:Dust / Q000032:analysis; D004553:Electric Conductivity; D004777:Environment; D004785:Environmental Pollutants / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis*; D008982:Molybdenum / Q000032:analysis; D012037:Refuse Disposal / Q000379:methods*; D012623:Seawater / Q000737:chemistry; D014866:Waste Products; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D060729:Coal Ash; D004391:Dust; D004785:Environmental Pollutants; D007220:Industrial Waste; D014866:Waste Products; D014874:Water Pollutants, Chemical; D014867:Water; D008982:Molybdenum
keywords: Building composites; Diffusion and dissolution; Leaching protocols; Long-term environmental impacts; Speciation of elements