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The paper presents the results of the study of feasibility of obtaining high-quality foamed thermal insulation materials based on a silicate matrix with addition of dolomite. It has been found out that the preliminary activation of a suspension based on a silica-containing component at a temperature of 90°C for 5-7 minutes allows accelerating the coagulation of silica fume and the synthesis of sodium silicates. Optimal foaming conditions for the charge frothing are 650-700°C for 25 minutes. There have been obtained foam silicates with a relatively uniform finely porous structure and stable physical and technical properties with density 0.38-0.48 g/cm³, strength up to 3 MPa, thermal conductivity 0.048-0.054 W/(m·K).

Substantial volumes of tailings and waste rocks placed in dumps create serious environmental and economic damage in mining areas and adjacent territories. The development of technologies for processing waste into heat-insulating building materials (foam glass) will make it possible to reduce the burden on the environment, as well as reduce the cost of finished building products. The article substantiates the possibility of obtaining block foamed materials for the production of heat-insulating materials based on man-made waste using low-temperature technology. The author investigated the ways of improving the operational properties of foam silicates by introducing modifying additives (apatite-nepheline waste, fly ash). To obtain foam silicates based on silica-containing waste, a liquid glass composition was prepared, into which additives were introduced. After molding and drying, the samples were swollen. Physical, chemical and thermal properties of foamed silicate materials made of silica-containing raw materials were determined taking into account the requirements of GOST for thermal insulation construction materials. To determine the thermal conductivity coefficient, an ITP-MG 4 electronic thermal conductivity meter was used. Microscopic studies were carried out using a SEM LEO 420 scanning microscope. The author of the article proposes the optimal compositions and conditions for obtaining foam materials that meet the regulatory requirements for materials and products for building insulation. Foamed materials with density up to 0.55 g/cm3, strength 5.5 MPa, water absorption 15–22 %, thermal conductivity 0.09–0.104 W•m/K were obtained. Foam glass materials have a wide range of properties: non-flammable, environmentally friendly, have a long service life, and are not subject to mold deterioration. The obtained materials can be recommended for use as thermal insulation in the construction and reconstruction of industrial and civil buildings and structures.

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