Abstract: A method for decontamination of steel components contaminated with radioactive material comprises the steps:(a) providing a mass of material including:(i) a proportion of steel carrying radioactive material; and(ii) a mass of slag forming material;(b) melting the mass of material, to provide a volume of molten steel and a volume of slag, the radioactive material originally present on the steel migrating to the slag; and(c) separating the slag from the molten steel. The mass of slag forming material is selected to provide a predetermined concentration of radioactive material in the slag. The concentration may be selected to be sufficiently dilute to allow disposal of the slag without restriction.

Abstract: Dealuminizing cast iron by contacting it with free-flowing flux particles having a solid silica core and a molten silica shell wherein said flux comprises silica and about 1% to about 5% calcium fluoride.

Abstract: A plant for the production of molten metals, includes a melting vessel and a metallurgical vessel receiving the melt from the melting vessel for aftertreating the melt and closed by a lid. The melting vessel has a tap opening for the melt provided on the bottom level of the melting vessel and located on the periphery of the melting vessel. The tap opening is positioned above a pour-in opening of the metallurgical vessel. In order to ensure a continuous melting procedure, the pour-in opening of the metallurgical vessel following the melting vessel is provided above a melt guiding chute arranged within the metallurgical vessel.

Abstract: For the metallurgical treatment of a molten metal bath (1) in a metallurgical smelting and refining vessel (3), additive substances (43) which are capable of flow, in particular lime, are supplied in a granular to dust state, at least during a part of the refining phase, to the upper region of the inward side (15') of the vessel wall (11), distributed around the periphery thereof. At the vessel wall (11) the additive substances (43) form a barrier or protective layer which reduces the energy losses and increases the service life of the vessel (3).

Abstract: A method for the preliminary treatment of molten hot metal for steel making comprising passing molten hot metal towards the downstream side in a horizontally disposed trough-like vessel and injecting obliquely downwards a powdered refining agent into the molten hot metal by use of an oxygen-containing gas as a carrier through one or more single-pipe nozzles installed on the side wall of the vessel with the nozzle port being positioned below the surface of the hot metal in the vessel.

Abstract: The invention contemplates smelting in a steelmaking unit a carbon-containing semiproduct, tapping it into a ladle, supplying to the ladle slag-forming materials, a reducer and thermally pretreated oxide materials containing alloying elements. The supply of said oxide materials is started after the tapping of the carbon-containing semiproduct in an amount of minimum 0.25 and maximum 0.5 by mass thereof, is carried out during the tapping of this semiproduct and completed before completing the tapping of the carbon-containing semiproduct. The supply of a reducer is carried out after the supply of said oxide materials and is completed before the end of the tapping of the carbon-containing semiproduct.

Abstract: A known "spark cup process" may be operated without the spark cup if the violent fluctuations in the melt surface with which the electric arc is struck are accommodated so as to allow the electric arc to be maintained substantially continuously. Controlling the dynamic profile of the melt surface without a spark cup allows continuous operation of the electric arc which generates enough plasma to permit addition of as much as 1000 lb/hr of a spray of superheated feed material to a flowing stream of melt which assimilates the feed material.

Abstract: A lime-based injection powder for use in steel-refining, having excellent waterproofing and desulphurization effects, consists of (a) more than 65% by weight of calcium oxide, (b) less than 30% by weight of fluorite, and 5-10% by weight of Al powder, 5%-7% by weight of the calcium oxide being converted into CaCO3 by reacting the calcium oxide with carbon dioxide in a multi-stage fluidized bed reactor.

Abstract: To produce deoxidized steel by the addition of deoxidizing agents to molten crude steel having an oxygen content of at least 200 ppm and the subsequent addition of alloying agents, the deoxidation is realized at least partially under the formation of liquid deoxidation products by the simultaneous addition of the two deoxidizing agents FeSi and FeMn. The method according to the invention ensures a great analytical precision of the steel and is not limited to the production of certain steels.