Leachability of Cr(VI) and other metals from asphalt composites with addition of filter dust.
The potential use of filter dust in asphalt composites for road construction was investigated. Filter dust contains high concentrations of metals, of which Cr(VI) and Pb are leached with water. Compact and ground asphalt composites with addition of 2% of filter dust by mass were studied. In order to evaluate their environmental impact, leachability tests were performed using water and salt water as leaching agents. The concentrations of Cr(VI) and Pb were determined in leachates over a time period of 182 days. The results indicated that Pb was not leached with leaching agents from asphalt composites. Cr(VI) was also not leached with leaching agents from compact asphalt composites. However, in ground asphalt composites, Cr(VI) was leached with water in concentrations up to 220 microg L(-1) and in salt water up to 150 microg L(-1). From the physico-mechanical and environmental aspects, filter dust can be used as a component in asphalt mixtures.
Vahcic
Mitja
M
Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
Milacic
Radmila
R
Mladenovic
Ana
A
Murko
Simona
S
Zuliani
Tea
T
Zupancic
Marija
M
Scancar
Janez
J
D002857:Chromium / Q000737:chemistry*; D003252:Construction Materials / Q000032:analysis*; D004391:Dust / Q000032:analysis*; D005374:Filtration; D006838:Hydrocarbons / Q000737:chemistry*; D012995:Solubility; D013997:Time Factors; D014874:Water Pollutants, Chemical
D004391:Dust; D006838:Hydrocarbons; D014874:Water Pollutants, Chemical; D002857:Chromium; C006647:asphalt