METHOD OF PREPARING LIGHT FILLER FOR CONCRETE Russian patent published in 1997 - IPC

FIELD: manufacture of building materials. SUBSTANCE: method includes preparation of blend by mixing (in wt %): 50-85 of sludge produced from wet gas-cleaning of furnaces smelting silicon-containing alloys; 3-8 iron-containing component; 1-8 lime-containing component; 5-30 clay component; and water to balance. Blend is then granulated. Granules are dried, preliminarily treated in oxidative medium: first at 450-660 C for 5- 15 min and then at 800-1000 C for 2-4 min with subsequent baking and simultaneous dusting with disperse refractory material. Method is distinguished with supplementing the blend with 1.5 wt % of lignosulfonate, whereas the blend and granules, upon dusting, may also be supplemented with product from dry gas-cleaning of lime- baking furnaces, and, as iron-containing component, blast furnace dust from oxygen-converter process may be utilized. EFFECT: reduced time of thermal treatment of granules and overhaul process time. 4 cl, 3 tbl