Carbonation of MSWI-bottom ash to decrease heavy metal leaching, in view of recycling
The 0.1-2 mm fraction of a MSWI-bottom ash cannot be used as granular construction material because leaching of Cu exceeds Flemish limit values. In addition, leaching of Ba, Mo and Sb exceeds informal limit values. Leaching characteristics thus need to be improved. Carbonation was the chosen treatme...
Veröffentlicht in: | Waste management (New York, N.Y.). - 1999. - 25(2005), 3 vom: 20., Seite 291-300 |
---|---|
1. Verfasser: | |
Weitere Verfasser: | , , , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2005
|
Zugriff auf das übergeordnete Werk: | Waste management (New York, N.Y.) |
Schlagworte: | Journal Article Metals, Heavy Soil Pollutants Carbon 7440-44-0 |
Zusammenfassung: | The 0.1-2 mm fraction of a MSWI-bottom ash cannot be used as granular construction material because leaching of Cu exceeds Flemish limit values. In addition, leaching of Ba, Mo and Sb exceeds informal limit values. Leaching characteristics thus need to be improved. Carbonation was the chosen treatment method and this was performed by placing samples in a CO2 chamber. The CO2 percentage and the temperature of the chamber atmosphere, as well as the initial humidity of the samples, were varied to optimize carbonation parameters. Metal leaching was tested with the EN 12457 extraction test. Carbonation decreased Cu leaching from 3.3 to 1.0 mg/kg, but not yet to below the official limit value of 0.5 mg/kg. Leaching of Mo and Sb remained fairly constant or even increased after carbonation, but their limit values are only informal. Ba leaching decreased to below the informal limit value. Carbonation also caused Cr leaching to increase, in some cases to above the official limit value. Of the tested parameters, a CO2 percentage of 10% and a carbonation temperature of 50 degrees C in the atmosphere, together with ash humidity between 13% and 25% appeared to give the best leaching results. The main carbonation reactions took place within the first 24 h |
---|---|
Beschreibung: | Date Completed 02.08.2005 Date Revised 12.04.2005 published: Print Citation Status MEDLINE |
ISSN: | 1879-2456 |