Technology of the porous granular material out of thermal power engineering waste

Abstract

The article presents the results of resource-saving technology development of porous granular material. Research is devoted to the development of scientific ideas about highly porous structures formation. The research objective is to develop a low-energy technology for producing porous granules based on the multiple use of thermal power engineering waste. Research novelty lies in conformity with a principle of combined porous structure’s formation of granules during thermal swelling of molding sand based on technogenic materials. Mixture of liquid sodium glass, fly ash and ash aluminosilicate microsphere has been developed to obtain the granules. Techniques for granulating liquid glass mixture have been developed. The parameters for thermal treatment of granules have been established to ensure formation of a strong, porous, and water-resistant structure. Physicomechanical and thermal properties of porous granules fired at a temperature of 350°С were studied. Microstructure of the fired granules was studied; their porosity is of 78 – 80%, bulk density is 210 – 230 kg/m3, and the thermal conductivity coefficient is 0.084 – 0.085 W/(m·°С). There has been developed a technological scheme for production of a granular material based on finely dispersed thermal power engineering waste. Comparative analysis of characteristics of the developed material and expanded clay was carried out.