| 摘要 |
A refractory insulating material which is tough and excellent in heat-insulating and fire-resisting properties is produced by mixing a first material containing silicon dioxide, calcium sulfate, aluminum oxide, etc., with a second material containing vegetable fibers, such as cellulose fiber, or chemical fibers, such as polyacrylonitrile fiber, and further with water glass and drying the mixture to solidify the same without the necessity for melting at high temperature. It is preferable that the first material contains silicon dioxide, calcium sulfate and aluminum oxide in a total of at least 40 % by weight. Also it is preferable that the refractory insulating material be composed of, before drying and solidification, 60.0-88.5 wt.% of the first material, 1.5-20.0 wt.% ofthe second material and 10.0-20.0 wt.% of the water glass. The water glass is either an aqueous solution of sodium silicate with a density of 1,255-1,710 kg/m<3> at 25 DEG C or an aqueous solution of potassium silicate with a density of 1,250-1,420 kg/m<3> at 25 DEG C. The reuse of waste material containing a large amount of silicon dioxide, gypsum and the like, such as powdery slag discharged from ironworks, powdery stone from stoneworks, or gypsum-containing waste from phosphatic fertilizer plants, as the first material will serve as a means for treating waste material. |
