title: Accelerated ageing of an EAF black slag by carbonation and percolation for long-term behaviour assessment.
abstract: The efficient reuse of industrial by-products, such as the electric arc furnace (EAF) black slag, is still hindered by concern over their long-term behaviour in outdoor environments. The aim of this study was to develop an accelerated ageing method to simulate the long-term natural carbonation of EAF slag exposed to the elements. The degree of carbonation achieved in a freshly produced slag after accelerated ageing and in a slag used on a fifteen-year-old unpaved road was very similar. The influence of particle size on accelerated carbonation was assessed, with it being concluded that the slag sample with a particle size bigger than 5-6 mm underwent slight carbonation over time when it was exposed to CO2. The accelerated ageing procedure based on percolating a previously carbonated water solution through the slag column allowed gradual leaching with simulated acid rain, as well as providing information about the gradual and total chemical release from the slag. Three classification groups were established according to the release rate of the determined elements. The joint use of the accelerated carbonation method and the percolation test is proposed as a useful tool for environmental risk assessment concerning the long-term air exposure of EAF black slag.
authors.affiliation: University of the Basque Country (UPV/EHU), Department of Chemical and Environmental Engineering, Faculty of Engineering, Alameda Urkijo s/n, 48013 Bilbao, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Gurtubay
authors.affiliation: University of the Basque Country (UPV/EHU), Department of Chemical and Environmental Engineering, Faculty of Engineering, Alameda Urkijo s/n, 48013 Bilbao, Spain. Electronic address: gorkajavier.gallastegui@ehu.es.
authors.forename: G
authors.initials: G
authors.lastname: Gallastegui
authors.affiliation: University of the Basque Country (UPV/EHU), Department of Chemical and Environmental Engineering, Faculty of Engineering, Alameda Urkijo s/n, 48013 Bilbao, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Elias
authors.affiliation: University of the Basque Country (UPV/EHU), Department of Chemical and Environmental Engineering, Faculty of Engineering, Alameda Urkijo s/n, 48013 Bilbao, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Rojo
authors.affiliation: University of the Basque Country (UPV/EHU), Department of Chemical and Environmental Engineering, Faculty of Engineering, Alameda Urkijo s/n, 48013 Bilbao, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Barona
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry; D002254:Carbonates / Q000737:chemistry*; D007220:Industrial Waste; D010316:Particle Size; D018570:Risk Assessment; D013232:Steel
chemical_list: D002254:Carbonates; D007220:Industrial Waste; D013232:Steel; D002245:Carbon Dioxide
keywords: Accelerated ageing; Carbonation; EAF black slag; Leaching; Percolation; Road building