EXPERIMENTAL MANUFACTURE OF CELLULAR GLASS FROM GLASS WASTE IN THE MICROWAVE REACTOR

Abstract

Experimental results of the process of manufacturing cellular glass from glass waste and calcium carbonate (between 1.1-1.4 wt.%) in a microwave reactor are presented in the paper. Compared to all previous experiments, a significantly larger amount of raw material powder mixture was heated to 817-828 ºC in a 3 kW-microwave reactor. The physical characteristics of the cellular glass samples were excellent: apparent density between 0.13-0.16 g/cm³, porosity between 92.7-94.1% and thermal conductivity in the range 0.041-0.046 W/m·K. The compressive strength had low values (1.09-1.18MPa), but in acceptable limits for using the cellular glass as an insulating material in construction. The specific energy consumption was higher (1.59-1.84 kWh/kg) due to the 15 mm-thickness of the wall of the silicon carbide crucible that fully absorbs the microwave radiation, the heating of the glass being indirect.