A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Stabilization of automotive shredder residue by calcium sulfoaluminate cement
Every year in EU nations, it is estimated that three million tonnes of automotive shredder residue (ASR) are generated. Half part of ASR is composed of rubber, textiles and plastics, which can be either transformed into alternative fuel or recycled. The second half, which is landfilled, is incombustible and has not yet been valorized. This waste still being thrown away contains 30 % organic matter, as well as inorganic compounds as quartz, calcite, magnetite, hematite, and anhydrite. It is also very rich in zinc (1 to 3.5 %) and lead (0.7 to 3.3 %). These elements are powerful retarders of ordinary Portland cement. For this reason, one new way of processing has been investigated: introduction of ASR directly into concrete with the use of calcium sulfoaluminate cement. This is especially interesting for engineers and scientists. As established by leaching tests, zinc and lead are integrated and fixed in the structure of ettringite, the main hydration product of calcium sulfoaluminate cement. Therefore, it is possible to produce concrete for some applications including road construction from this currently landfilled 'waste' (i.e., the ASR is shown to be useful recyclable material into an environmentally friendly 'green' concrete). The quantity of ISR is important in concrete (ISR/CSA=3.78) and heavy metals (zinc and lead) are efficiently and effectively immobilized, as proved by leaching test. The use of CSA aline is not sufficient to immobilize residual organics contained in ISR.
Stabilization of automotive shredder residue by calcium sulfoaluminate cement
Every year in EU nations, it is estimated that three million tonnes of automotive shredder residue (ASR) are generated. Half part of ASR is composed of rubber, textiles and plastics, which can be either transformed into alternative fuel or recycled. The second half, which is landfilled, is incombustible and has not yet been valorized. This waste still being thrown away contains 30 % organic matter, as well as inorganic compounds as quartz, calcite, magnetite, hematite, and anhydrite. It is also very rich in zinc (1 to 3.5 %) and lead (0.7 to 3.3 %). These elements are powerful retarders of ordinary Portland cement. For this reason, one new way of processing has been investigated: introduction of ASR directly into concrete with the use of calcium sulfoaluminate cement. This is especially interesting for engineers and scientists. As established by leaching tests, zinc and lead are integrated and fixed in the structure of ettringite, the main hydration product of calcium sulfoaluminate cement. Therefore, it is possible to produce concrete for some applications including road construction from this currently landfilled 'waste' (i.e., the ASR is shown to be useful recyclable material into an environmentally friendly 'green' concrete). The quantity of ISR is important in concrete (ISR/CSA=3.78) and heavy metals (zinc and lead) are efficiently and effectively immobilized, as proved by leaching test. The use of CSA aline is not sufficient to immobilize residual organics contained in ISR.
Stabilization of automotive shredder residue by calcium sulfoaluminate cement
Stabilisierung von Fahrzeug-Schredderrückständen durch Calciumsulfoaluminat-Zement
Pera, Jean (author) / Ambroise, Jean (author)
2004
6 Seiten, 2 Bilder, 3 Tabellen, 11 Quellen
Conference paper
English
Auslaugen (Verfahrenstechnik) , Beton , Blei , Brennstoff , Deponie , Ettringit , Fahrzeug , Recycling , Schredderschrott (Metall) , Straßenbau , Sulfoaluminat , Zement , Zink