Abstract: A method of producing a graphite-containing refractory within which carbon fiber bundles are placed, the graphite constituting 1% to 80% by mass, the method including a bundling step of bundling carbon fibers to form the carbon fiber bundles; a mixing step of mixing a refractory raw material with graphite to prepare a graphite-containing refractory raw material; a pressing step of pressing the graphite-containing refractory raw material in which the carbon fiber bundles are placed to prepare a formed product; and a drying step of drying the pressed product, wherein the bundling step includes bundling 1000 to 300000 of the carbon fibers with a fiber diameter of 1 to 45 ?m/fiber to form carbon fiber bundles 100 mm or more in length.

Abstract: A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 ?m/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

Abstract: A method of producing a graphite-containing refractory within which carbon fiber bundles are placed, the graphite constituting 1% to 80% by mass, the method including a bundling step of bundling carbon fibers to form the carbon fiber bundles; a mixing step of mixing a refractory raw material with graphite to prepare a graphite-containing refractory raw material; a pressing step of pressing the graphite-containing refractory raw material in which the carbon fiber bundles are placed to prepare a formed product; and a drying step of drying the pressed product, wherein the bundling step includes bundling 1000 to 300000 of the carbon fibers with a fiber diameter of 1 to 45 ?m/fiber to form carbon fiber bundles 100 mm or more in length.

Abstract: A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 ?m/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

Abstract: The slag in a molten state formed at a step of refining stainless steel is adjusted such that the slag has a basicity in the range of 1.3-4.0, and the slag is mixed with a sulfur-containing material wherein the sulfur is zero or minus in valence, thereby setting the concentration of sulfur in the slag to be not less than 0.2% by weight. The slag is so modified that Cr6+ is substantially completely prevented from being eluted and can be effectively utilized as a roadbed material and a reclamation material for civil works. The slag is quenched at such a speed of cooling that the temperature of the slag is decreased from 1200° C. to 400° C. within 48 hours so that noticeable effects are attained.

Abstract: A method of rapidly reducing chromium oxide-containing slag and the like in large quantities, in a simplified manner and without requiring high temperatures. Chromium oxides are reduced with at least one of elementary sulfur and compounds of sulfur having a valence less than 6. For an aqueous solution of the sulfur component, desirably, its sulfur content is more than 0.03% by weight. As the sulfur source, preferred is blast furnace slag (e.g., non-aged, gradually-cooled blast furnace slag) that is discharged in large quantities in the iron industry. Cr6+ in chromium oxides is reduced in one of the following ways: (a) Chromium oxide-containing substances are sprayed with or immersed in blast furnace slag-released water that has been used in cooling blast furnace slag. (b) Chromium oxide-containing substances are mixed with blast furnace slag, and then kept in an air atmosphere. Optionally, the mixture is sprayed with blast furnace slag-released water.

Abstract: A method of rapidly reducing chromium oxide-containing slag and the like in large quantities, in a simplified manner and without requiring high temperatures. Chromium oxides are reduced with at least one of elementary sulfur and compounds of sulfur having a valence less than 6. For an aqueous solution of the sulfur component, desirably, its sulfur content is more than 0.03% by weight. As the sulfur source, preferred is blast furnace slag (e.g., non-aged, gradually-cooled blast furnace slag) that is discharged in large quantities in the iron industry. Cr6+ in chromium oxides is reduced in one of the following ways: (a) Chromium oxide-containing substances are sprayed with or immersed in blast furnace slag-released water that has been used in cooling blast furnace slag. (b) Chromium oxide-containing substances are mixed with blast furnace slag, and then kept in an air atmosphere. Optionally, the mixture is sprayed with blast furnace slag-released water.

Abstract: A method of rapidly reducing chromium oxide-containing slag and the like in large quantities, in a simplified manner and without requiring high temperatures. Chromium oxides are reduced with at least one of elementary sulfur and compounds of sulfur having a valence less than 6. For an aqueous solution of the sulfur component, desirably, its sulfur content is more than 0.03% by weight. As the sulfur source, preferred is blast furnace slag (e.g., non-aged, gradually-cooled blast furnace slag) that is discharged in large quantities in the iron industry. Cr6+ in chromium oxides is reduced in one of the following ways: (a) Chromium oxide-containing substances are sprayed with or immersed in blast furnace slag-released water that has been used in cooling blast furnace slag. (b) Chromium oxide-containing substances are mixed with blast furnace slag, and then kept in an air atmosphere. Optionally, the mixture is sprayed with blast furnace slag-released water.

Abstract: A method of solidifying a steel-making slag is performed by subjecting a mixture of a steel-making slag containing at least about 50% by weight of a powdery steel-making slag having a particle size not greater than about 5 mm and a substance containing at least about 30% by weight of SiO2 (e.g., a fly ash and/or the fine powder of a granulated blast furnace slag) to a hydration reaction. The resulting solidified material contains at least about 20% of a tobermorite phase, has high strength and is suitable as an inorganic material useful as a roadbed material, building and civil engineering materials, etc.

Abstract: A flame spray mending material effective for applying a dense thermal spray mending layer to a silica brick wall of an industrial furnace, having a high crystallization ratio immediately after thermal spraying in a broad thermal spray condition, having an oxide concentration of 89% by weight or more of SiO2, more than 2.0 to 4.0% by weight of Na2O and/or more than 0.2 to 4.0% by weight of Li2O, having a 80% or more crystallization ratio after thermal spraying and 200 kgf/cm2 or more compression strength. A slight amount of CaO may be present to make a flame spray mending material with an oxide concentration of 89% by weight or more of SiO2, more than 2.0 to 5.0% by weight of CaO, 0.5 to 4.0% by weight of Na2O and/or more than 0.2 to 4.0% by weight of Li2O, and 1.0% by weight of less of Al2O3.