Coal combustion wastes are often used as sources of raw materials, but their utilization degree is still relatively low. Therefore, a greater exploitation in the consolidated fields of use must be pursued and new applications have to be searched for. In view of the manufacture of preformed building elements based on ettringite (a calcium trisulphoaluminate hydrate characterized by good mechanical strength and low density), it has been investigated the hydration behaviour of a sulpho-calcic fly ash generated in an industrial coal combustor. Curing was performed at 70°C up to 4 aging days. X-ray diffraction and thermogravimetric analyses have assessed the fly ash ability to give ettringite as main reaction product within the hydrated system. Calcium hydroxide in the concentration range of about 15-18% was detected. The ettringite amount was comprised between about 43% (1d-curing) and 58% (4d-curing).
Hydration of coal combustion wastes aimed at obtaining ettringite-based materials / G., Bernardo; M., Marroccoli; Montagnaro, Fabio; G. L., Valenti. - STAMPA. - (2001), pp. 498-502. (Intervento presentato al convegno 3rd Congress on Added Value and Recycling of Industrial Waste tenutosi a L'Aquila, Italy nel 25-29 Giugno).
Hydration of coal combustion wastes aimed at obtaining ettringite-based materials
MONTAGNARO, FABIO;
2001
Abstract
Coal combustion wastes are often used as sources of raw materials, but their utilization degree is still relatively low. Therefore, a greater exploitation in the consolidated fields of use must be pursued and new applications have to be searched for. In view of the manufacture of preformed building elements based on ettringite (a calcium trisulphoaluminate hydrate characterized by good mechanical strength and low density), it has been investigated the hydration behaviour of a sulpho-calcic fly ash generated in an industrial coal combustor. Curing was performed at 70°C up to 4 aging days. X-ray diffraction and thermogravimetric analyses have assessed the fly ash ability to give ettringite as main reaction product within the hydrated system. Calcium hydroxide in the concentration range of about 15-18% was detected. The ettringite amount was comprised between about 43% (1d-curing) and 58% (4d-curing).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
