Abstract: A process of producing iron from fine-grained iron ore by direct reduction, which includes adding oxygen, sponge iron and at least one of coal fines and low-temperature carbonized coal to an iron bath in a melt gasifier to produce a reducing gas, regulating the temperature of the reducing gas by blowing coal fines into it to produce a cooled reducing gas and a low-temperature carbonized coal, separating the low-temperature carbonized coal from the cooled reducing gas in order to use the separated low-temperature carbonized coal in the melt gasifier, preheating a fine-grained iron ore with a used reducing gas containing carbon monoxide to a temperature from 450.degree. to 700.degree. C., and reducing the preheated fine-grained iron ore with the cooled reducing gas at a temperature from 700.degree. to 1100.degree. C.

Abstract: Process for the reduction of iron containing chrome ores in which a mixture of chrome ore, coal and slag producers with an ore-coal ratio of 1:0.4 to 1:2 is heated in a rotating furnace in a CO containing atmosphere to temperatures of between 1100.degree. and 1580.degree. C. and in which the rotating furnace is heated in counter flow by a burner through the central nozzle of which oxygen and/or air is supplied. The burner is located at the reaction product discharge end of the furnace and 10 to 90% of the coal for the raw material mixture is introduced into the rotating furnace through the reaction product discharge end, with at least part of this coal being introduced through an outer nozzle of the burner.

Abstract: An electrically heated melting furnace, preferably a direct current electric arc furnace, having a floor provided with a lining of refractory material and with an electrode comprised of a plurality of electrically conductive paths formed of an electrically conductive material which extends through the lining of refractory material from the inner floor surface toward the exterior, wherein the service life of the lining is improved in that the electrically conductive paths are composed of layers of at least one high melting point nonmetallic material which are connected with the refractory material, and which have a thickness of at most 5 mm.

Abstract: A process for the production of ferrochromium from iron-containing chromium ores, in which the reduction of the ore, which is mixed with coal and slag-forming constituents, is conducted in a rotary kiln at 1480.degree. to 1580.degree. C. in the presence of a CO-containing atmosphere from 20 to 240 minutes, and in which melting follows in a melting furnace at 1600.degree. to 1700.degree. C. By this process, the greatest part of the gangue of the ore can be separated off before melting the reduced ore.

Abstract: A process for the production of ferromanganese from iron-containing manganese ores, in which the reduction of the ore, which is mixed with coal and slag-forming constituents, is conducted in a rotary kiln at 1200.degree. to 1350.degree. C. in the presence of a CO-containing atmosphere for 20 to 240 minutes, and in which melting follows in a melting furnace at 1400.degree. to 1600.degree. C. By this process, the greatest part of the gangue of manganese ore can be separated off before melting the reduced ore.

Abstract: The present invention provides a process for preventing foaming over in the case of converting pig iron into steel, as well as for lowering the phosphorus content, by blowing in oxygen in the presence of basic, slag-foaming materials, with the simultaneous blowing of finely particulate calcium carbide into and/or on to the melt, wherein finely particulate calcium carbide is introduced in an amount corresponding to the oxygen excess of the slag at the point of time at which the rate of decarbonizing increases, the slag foams up and/or the slag indicates an increased oxygen potential.The present invention also provides a composition and apparatus for carrying out this process.

Abstract: A method of performing a treatment of a dust cloud includes the successive steps of generating the dust cloud from a gas and from solid particles, passing the dust cloud through a reaction zone, separating the dust cloud into its components in a separator, and reintroducing at least one part of at least one component into the dust cloud. There is further formed a solids column into which fresh or recirculated solid particles are introduced. The solids column which seals the gas used for generating the dust cloud from the separator, is height-adjustable for controlling the concentration of solids in the dust cloud formed from the solid particles constituting the solids column.

Abstract: In order to melt iron-containing material, particularly sponge iron, in an electric furnace containing a molten metal mass underlying a molten slag mass, electrodes are immersed in the molten slag mass, a current is caused to flow between the electrodes and is converted into melting heat by the electrical resistance of the slag, and the number of charge carriers in the slag is adjusted to control the conductivity of the slag and thus the ratio of the current flowing through the slag to the current flowing through the molten metal.

Abstract: A method for producing steel from fine-grained iron ores includes the step of preheating and partially reducing the fine-grained iron ores in a countercurrent heat exchanger. The preheated and partially reduced fine-grained iron ores are then reduced in a fluidized bed reactor to form sponge iron. The reduction in the fluidized bed reactor is effected with exhaust gases which consist substantially of carbon monoxide and which emanate from a melting vessel in which sponge iron is melted. The fine-grained sponge iron produced in the fluidized bed reactor is separated from the reduction gases which form during the reduction in the fluidized bed reactor. The separated fine-grained sponge iron is pneumatically transported into a carbon containing melt in the melting vessel. The transported sponge iron is melted and subjected to a final reduction in the metal melt with the carbon in the metal melt and with further carbonaceous material which is pneumatically introduced into the metal melt.

Abstract: A method for melting sponge iron is provided in which pieces or pellets of sponge iron, which may be partly replaced by scrap, are placed on the surface of a molten metal bath. Oxygen is added to the metal bath at a position below the surface of the bath. Further substances required for the melting process are added to the metal bath under pressure at a position below the surface of the bath. The further substances that are added include solid carbonaceous dust and fine-grained sponge iron.

Abstract: A method is provided for producing steel from iron oxide-containing raw materials. The raw materials are initially converted, in a reduction furnace by direct reduction with a reducing gas, to a substantially metallized sponge iron. The metallized sponge iron is then melted with the addition of additives and possibly fine scrap in a melting vessel filled with a metal melt. Heat and carbon monoxide-containing exhaust gases are formed in the melting vessel due to the reaction of oxygen-containing gases with carbonaceous material. The heat is utilized in part to melt the sponge iron and the exhaust gases are utilized for the direct reduction. The melt is then transferred to a further vessel where it is further processed into steel by means of suitable metallurgical measures. In the process, the entire, strongly-heated exhaust gas from the melting vessel is caused to react in a reactor with (1) carbonaceous material, and with (2) water vapor and/or carbon dioxide.

Abstract: The present invention relates to a) a method for refining metal in which, e.g., oxygen and fine lime are introduced through at least one nozzle disposed below a molten bath surface in the refining vessel and a gas is fed in through one or a plurality of further nozzles associated with each first nozzle and to b) an apparatus for practicing the method.