Abstract: The present disclosure provides a facility to produce direct reduced iron, which makes it possible to perform reforming and reduction and adjust the carbon amount in a product within a wide range without requiring an externally heating reformer and without causing the metal dusting problem in a circulating gas preheater and the problem of sintering each other or fusion between reduced iron, in a furnace. The facility to produce the direct reduced iron according to the present invention is equipped with a water content control device for controlling the water content in a gas discharged from a shaft-type reduction furnace, a first gas mixing device for mixing the gas from which a portion of water has been removed with an oxygen-containing gas and a hydrocarbon-containing gas to produce a mixed gas, and an auto-thermal reformer for reforming the mixed gas with its energy.

Abstract: An apparatus for manufacturing molten metal has a stationary electric furnace, a raw material charging chute, and exhaust duct and a secondary combustion burner in the furnace top, and a shock generator. The raw material charging chute is in one end of the furnace in a width direction and an electric heating region is spaced from the raw material charging chute in the width direction. A raw material layer having a sloping surface extends downward from the one end of the furnace having the raw material charging chute toward the electric heating region, the sloping surface supporting a metal agglomerate raw material layer. The shock generator is provided at least partially within the raw material and extends to the sloping surface, to be in contact with the metal agglomerate raw material layer, and to mechanically overcome hanging of the metal agglomerate raw material layer on the sloping surface.

Abstract: Disclosed is a production device of which secondary combustion efficiency can be further improved when a molten metal is produced by directly reducing and melting a metal agglomerate raw material layer in an electric heating furnace. Specifically, material charging chutes (4, 4) are disposed at either end portion (2, 2) of a furnace in the width direction of the furnace. Electrodes (5) are disposed in a central region in the furnace width direction. Secondary combustion burners (6) are disposed in an upper portion (1) of the furnace having stepped portions descending from both end portions (2, 2) in the furnace width direction to the electrodes (5). Raw material layers (12) each having a downslope inclined to lower portions of the electrodes (5) are formed in advance by charging a carbonaceous material (A) from the chutes (4, 4), and metal agglomerate raw material layers (13) are formed on the slopes of the raw material layers (12) by charging metal agglomerate raw material (B).

Abstract: The present invention provides a method for producing direct reduced iron and/or hot metal using high-moisture content carbonaceous material, including: agglomerating carbonaceous material from the high-moisture content carbonaceous material with a metal oxide-bearing material to form an agglomerate suitable for use in a direct reduction and/or hot metal producing process. The method also includes distilling the high-moisture content carbonaceous material. The method further includes dry quenching the carbonaceous material obtained from the distilling step. The method still further includes drying the high-moisture content carbonaceous material with energy from a hot off gas from a furnace for producing direct reduced iron and/or hot metal prior to the distilling step.

Abstract: The present invention relates generally to a smelting operation or the like, by which molten metal is produced from a metal oxide after metal oxide agglomerates are directly reduced and melted with a carbonaceous material in an electric heating and melting furnace. More specifically, the present invention relates to an electric furnace for producing molten metal that has material recycling capability, especially in-process material recycling capability.

Abstract: A method for manufacturing molten metal by using a stationary non-tilting electric furnace comprising: forming a raw material layer by charging a particular amount of a carbonaceous material and/or metal oxide agglomerates with carbonaceous material containing a nonvolatile metal element that forms molten metal into the furnace from the raw material charging chute, and having a sloping surface extending downward from the one end of the furnace toward the other end of the; subsequently forming an agglomerate layer on the sloping surface of the raw material layer by charging a particular amount of the metal oxide agglomerates with carbonaceous material into the furnace from the raw material charging chute; and subsequently forming a molten metal layer and a molten slag layer in the furnace by heating the lower end of the agglomerate layer with the heater.

Abstract: An object of the present invention is to produce briquettes that have high strength even when the amounts of binder and water used are decreased as much as possible. A method for producing briquettes that achieve this object includes a step of forming primary granules by using a powder containing a metal oxide and at least one of zinc oxide, lead oxide, and titanium oxide and a step of compressing the primary granules still containing the at least one of zinc oxide, lead oxide, and titanium oxide so as to mold the primary granules into secondary granules.

Abstract: The present invention relates generally to a smelting operation or the like, by which molten metal is produced from a metal oxide after metal oxide agglomerates are directly reduced and melted with a carbonaceous material in an electric heating and melting furnace. More specifically, the present invention relates to an electric furnace for producing molten metal that has material recycling capability, especially in-process material recycling capability.

Abstract: Disclosed is a molten metal producing device capable of effectively preventing a hanging of a metal agglomerate raw material layer and capable of reliably removing hanging even if the hanging occurs. Raw material for forming the raw material layer (A) and metal agglomerate raw material (B) are charged in this order from raw material charging chutes (4,4) at either end portion (2,2) of a stationary non-tilting arc furnace in the width direction of the furnace so as to form raw material layers (12) each having a sloping surface extending downward to the portions of electrodes (5) disposed in a central region in the furnace width direction and metal agglomerate raw material layers (13) on the slopes, respectively. Molten iron is produced by sequentially melting lower end portions of the metal agglomerate raw material layers (13) by arc heating at the electrodes (5).

Abstract: Disclosed is a production device of which secondary combustion efficiency can be further improved when a molten metal is produced by directly reducing and melting a metal agglomerate raw material layer in an electric heating furnace. Specifically, material charging chutes (4, 4) are disposed at either end portion (2, 2) of a furnace in the width direction of the furnace. Electrodes (5) are disposed in a central region in the furnace width direction. Secondary combustion burners (6) are disposed in an upper portion (1) of the furnace having stepped portions descending from both end portions (2, 2) in the furnace width direction to the electrodes (5). Raw material layers (12) each having a downslope inclined to lower portions of the electrodes (5) are formed in advance by charging a carbonaceous material (A) from the chutes (4, 4), and metal agglomerate raw material layers (13) are formed on the slopes of the raw material layers (12) by charging metal agglomerate raw material (B).

Abstract: The present invention provides a method for producing direct reduced iron and/or hot metal using high-moisture content carbonaceous material, including: agglomerating carbonaceous material from the high-moisture content carbonaceous material with a metal oxide-bearing material to form an agglomerate suitable for use in a direct reduction and/or hot metal producing process. The method also includes distilling the high-moisture content carbonaceous material. The method further includes dry quenching the carbonaceous material obtained from the distilling step. The method still further includes drying the high-moisture content carbonaceous material with energy from a hot off gas from a furnace for producing direct reduced iron and/or hot metal prior to the distilling step.

Abstract: A rotary hearth furnace includes an exhaust gas eductor. The exhaust gas eductor includes a compartment-defining portion and an exhaust duct. The compartment-defining portion is provided on part of a ceiling of the rotary hearth furnace in an exhaust gas discharge region, and an exhaust duct is connected to the compartment-defining portion. The lower surface of the compartment-defining portion lies higher than the lower surface of the other portion of the ceiling. The compartment-defining portion defines a compartment where the exhaust gas stays. The exhaust duct can include a cooling medium injection nozzle. The furnace increases fuel efficiency by completely burning combustible components remaining in exhaust gas generated in the rotary hearth furnace so as to use the combustible components efficiently for the heating and reduction reaction in the rotary hearth furnace, without problems in producing reduced iron.

Abstract: A screw conveyor for conveying an object to be conveyed, supported by a casing 1 by rotation of a screw 2, in which wear of a screw blade and decrease in conveyance efficiency are prevented without the need for extra power. Load on an electric motor 3 or the like for rotating the screw 2 or a value corresponding to the load is measured, and if the value is equal to or larger than a preset upper limit value, a screw shaft 2a is lifted up to increase a gap between an edge of the screw blade 2b and a bottom portion of the casing 1.

Abstract: An object of the present invention is to produce briquettes that have high strength even when the amounts of binder and water used are decreased as much as possible. A method for producing briquettes that achieve this object includes a step of forming primary granules by using a powder containing a metal oxide and at least one of zinc oxide, lead oxide, and titanium oxide and a step of compressing the primary granules still containing the at least one of zinc oxide, lead oxide, and titanium oxide so as to mold the primary granules into secondary granules.

Abstract: To provide a rotary hearth furnace which has a simple furnace structure in which the furnace is not damaged even if the furnace is operated for a long term while presenting general equations capable of adequately determining a thermal expansion margin in the rotary hearth furnace.

Abstract: A method for manufacturing molten metal by using a stationary non-tilting electric furnace including: a raw material charging chute that is provided in one end of the furnace in the width direction, and is connected to the interior of the furnace from the upper part of the furnace, an electrical heater that heats a lower position of the furnace in the height direction is located in the other end of the furnace in the width direction, and a secondary combustion burner that is provided at the furnace top and between the two ends of the furnace.

Abstract: A rotary hearth furnace includes an exhaust gas eductor. The exhaust gas eductor includes a compartment-defining portion and an exhaust duct. The compartment-defining portion is provided on part of a ceiling of the rotary hearth furnace in an exhaust gas discharge region, and an exhaust duct is connected to the compartment-defining portion. The lower surface of the compartment-defining portion lies higher than the lower surface of the other portion of the ceiling. The compartment-defining portion defines a compartment where the exhaust gas stays. The exhaust duct can include a cooling medium injection nozzle. The furnace increases fuel efficiency by completely burning combustible components remaining in exhaust gas generated in the rotary hearth furnace so as to use the combustible components efficiently for the heating and reduction reaction in the rotary hearth furnace, without problems in producing reduced iron.

Abstract: A screw conveyor for conveying an object to be conveyed, supported by a casing 1 by rotation of a screw 2, in which wear of a screw blade and decrease in conveyance efficiency are prevented without the need for extra power. Load on an electric motor 3 or the like for rotating the screw 2 or a value corresponding to the load is measured, and if the value is equal to or larger than a preset upper limit value, a screw shaft 2a is lifted up to increase a gap between an edge of the screw blade 2b and a bottom portion of the casing 1.

Abstract: PROBLEM TO BE SOLVED: To provide a rotary hearth furnace which has a simple furnace structure in which the furnace is not damaged even if the furnace is operated for a long term while presenting general equations capable of adequately determining a thermal expansion margin in the rotary hearth furnace.

Abstract: A sealing structure for a solid-transferring screw installed inside a heating furnace such as a material-leveling screw and a product-discharging screw, the sealing structure enabling the solid-transferring screw to be lifted during operation while airtightness of the heating furnace is retained. A driving shaft of the solid-transferring screw passes through through-holes formed in side walls of the heating furnace and is supported by liftable supporting devices disposed outside the furnace. Sealing blocks are attached on outer edges of the through-holes to surround the periphery of the through-holes at the outside of the furnace. Sliding panels are disposed at outer sides of the sealing blocks and have sliding holes for sliding the screw-driving shaft so that the driving shaft extends through the sliding holes. The sliding panels are brought into contact with the sealing blocks via the sealing members therebetween so that the sliding panels are slidable in the vertical direction.