OPTIMIZATION OF THE HEAT-TREATMENT REGIME OF A SINTERED GLASS-CERAMIC FROM MSWI BOTTOM ASH

10th International Multidisciplinary Scientific GeoConference - SGEM2010, www.sgem.org, SGEM2010 Conference Proceedings/ ISBN 10: 954-91818-1-2, June 20-26, 2010, Vol. 2, 893-900 pp

ABSTRACT

The aim of this work is the optimization of sinter-crystallization regime of a glassceramic
from a municipal solid waste incineratior (MSWI) bottom ash. The parent
waste was melted at 1400oC, milled below 75 μm and the obtained glass powders were
pressed at 100 MPa. The optimal temperature for sinter-crystallization was estimated by
DTA, dilatometry and XRD. Subsequently, the degrees of sintering, obtained at
different heating rates (between 2 and 40oC/min) and 1 h step at 950oC were estimated
by the linear shrinkage and water absorption. Using precise density measurements with
gas pycnometer, the open and closed porosities in samples were also evaluated. The
structure of glass-ceramics, obtained at low and high heating rates, were observed by
SEM and compared. It was demonstrated that samples with no deformation, zero water
soaking and good crystallinity can be obtained at high heating rate of 40oC/min. This
gives a possibility to apply short and cost-effective heat-treatment regimes.

Keywords: industrial wastes, sintering, glass-ceramics