METHOD OF PREPARING GRANULAR HEAT-INSULATING MATERIAL Russian patent published in 2002 - IPC

FIELD: building materials industry, more particularly manufacture of granular heat-insulating material. SUBSTANCE: high-module liquid glass having silicate module of 4-7 is prepared, raw granules are granulated and heat treated. High-module glass is prepared by hydrothermal treatment at 68-73 C and atmospheric pressure for 5-10 min of suspension from silica-containing crystalline micosilica waste resulting from crystalline silicon waste which comprises 83-93 wt % of SiO₂ and 6-16 wt parts of carbon impurities such as graphite (C) and carborundum (SiC) in alkaline solution of sodium hydroxide at L/S phase ratio of 0.94-1.008, and raw granules are heat treated at 350-400 C for 20-30 min. EFFECT: more efficient preparation method. 2 tbl _