A process for the production of silica brick material which contains finely divided SiO2

摘要

1378452 Refractory brick ELKEM AS 17 April 1972 [26 April 1971] 17623/72 Heading C1J A silica brick is made by kneading a mixture of finely divided SiO 2 containing material (e.gthe SiO 2 dust from metallic silicon smelting processes), and lime in the presence of water, adding to this mixture during the kneading an ammonium salt of an acid which can form an essentially water-insoluble Ca salt, shaping the kneaded mixture and firing. Preferably firing takes place by slow heating through 800-900‹C. to produce tridymite before raising the temperature to 1400‹C. A pre forming agent. e.g. sawdust may be included in the mixture, The preferred ammonium salts are the carbonate, hydrogen carbonate or onalate.