Ash-and-Slag-Waste-based Porous Glass: Synthesis and Properties

Abstract

In recent years, porous glass (sponge-glass) is becoming increasingly popular as an environmentally and hygienically safe non-flammable insulating material in the construction of civil and industrial buildings and structures. Composite materials with sponge-glass can be used for exterior insulation and facade finish. These materials are characterized by sufficiently high insulating effect, mechanical strength and chemical durability in combination with low cost of their production. Ash and slag waste from thermal power plants can be used as one of the main raw materials for the production of sponge-glass for construction purposes. The paper presents the results of research on the development and study of the properties of porous glass on the basis of ash and slag wastes of the Novotcherkasskaya GRES and bottled glass scrap: various compositions of the furnace charge have been synthesized, the influence of the fluxing agent and blowing agent on the functional properties of porous glass (density, porosity, strength and heat conduction) has been studied. Crystalline borax was used as the fluxing agent, and anthracite as the foaming agent. Standard methods were used for the study: electron microscopy methods, measurements of heat fluxes (tests were carried out in two modes: cooling and heating), determination of apparent density, etc., qualified equipment. The following was established in the course of study: the porosity of porous glass samples increases by more than two times with an increase in the anthracite additive; with an increase in the anthracite additive the strength of the porous glass decreases by more than 1.5 times; the optimal composition of the furnace charge, taking into account the effect of anthracite on the most important properties of the synthesized porous glass, is SHPS-B5 composition, which provides a sufficiently high porosity of 37.7% and a density of 466.8 kg/m3.