Optimization of the heat-treatment regime of a sintered glass-ceramic from mswi bottom ash

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 1400°C, 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 40°C/min) and 1 h step at 950°C 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 40°C/min. This gives a possibility to apply short and cost-effective heat-treatment regimes. © SGEM2010 All Rights Reserved by the International Multidisciplinary Scientific GeoConference SGEM Published by STEF92 Technology Ltd