A Study of Thermophysical Properties of a Glass-Ceramic Material Modified with Low-Melting and Organic Additives for Thermal Insulation of Pipelines

A granular insulating crystalline glass material based on broken glass, clay and organic additives and a technology for its manufacturing are proposed. The regularities of the effect of the composition and firing temperature on the properties of the granules are specified. The granular heat-insulating material is produced following characteristics: its bulk density is 260-280 kg/m(3), pellet strength - 1.74 MPa, thermal conductivity - 0.075 W/(m degrees C), and water absorption - 2.6 wt.%. The effect of the basic physical characteristics of the charge components on the pore formation process is studied. Using the research results, the basic parameters affecting the sustainability of the swelling glass are specified. A reasonable charge composition and a thermal and gas synthesis mode are chosen for the partial gas pressure to be lower than the surface tension of the melt. This enables the formation of granules with small closed pores and vitrified surfaces. The data obtained could be applied in heat insulation of the main pipelines with foamed glass ceramics.