METHOD OF HOLLOW FILLING AGENT PRODUCING Russian patent published in 2002 - IPC

FIELD: industry of building materials. SUBSTANCE: invention relates to production of hollow filling agent for concrete obtained by means of the burning out core. Method of producing the hollow filling agent involves forming the burning out core, application of mineral envelope on it followed by roasting granules prepared. Before forming the burning out core the thickened excessive silt from biological sewage constructions with moisture 97-98% is mixed with brick clay with moisture 20-25% and sand trap deposits with moisture 93-95%. The ground quartz sand with specific surface 700-800 cm²/g is used as a mineral envelope followed by drying the formed granules at heating to 150-200 C and their following heating to 700-1000 C. Roasting is carried out at 1100-1500 C with the further heating to 1500 C and keeping at this temperature for 7-8 min. The ratio of components in mixture for the burning out core forming, wt.-%: indicated silt, 25-30; brick clay, 50-60; deposit from sand traps, 0.5-1.0; crude deposit from settling tanks, 14-19.5. Invention provides decrease of core density and filling density of hollow filling agent, enhanced porosity and strength, increased heat- and sound insulation, utilization of sediments. EFFECT: improved method of production. 1 tbl