Nonconventional Technologies Review (Sep 2020)
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.