POROUS REFRACTORY MULLITE MATERIAL AND METHOD OF ITS MANUFACTURE Russian patent published in 2002 - IPC

FIELD: manufacture of porous highly refractory mullite materials and articles made from such materials; manufacture of building materials for ferrous and non-ferrous metallurgy; thermal power complexes; chemical and oil-refining industries and other industries. SUBSTANCE: porous refractory mullite material contains 50-78 mas.% of mullite of composition xAl₂O₃ and ySiO₂ at content of x 66-72 mas.% and y 28-34 mas.% of materials synthesized by exothermic reaction proceeding in hardened porous material produced by mixing ground mineral charge including silicon and aluminum dioxide with gas-forming agent - crystal silicon preliminarily activated through fine grinding to size of particles of <100 mcm and mixed with water glass at pH>8 at the following ratio of components, mas.%: silicon dioxide: aluminum, (1.5-9.0) : 1; water glass : silicon, (2-6) : 1; and charge water glass, (1.0 to 1.5) : 1. Proposed method uses minerals charge which includes ferrum, chromium, aluminum, magnesium oxides or their mixtures. Porous refractory materials with mullite structure obtained according to proposed method have density of 55-65%, heat conductivity at 20 C of 0.06-0.10 W/mK and may be used for lining, brickwork and repair jobs on thermal units of any type. EFFECT: enhanced efficiency. 4 cl, 2 tbl