Abstract: A direct reduction method and system including an electric heater system adapted to heat a reduction gas and a shaft furnace adapted to receive and utilize the heated reduction gas and one or more of a carbonaceous gas and/or material to produce the direct reduced iron containing carbon, including: providing the reduction gas to an electric heating elements of the electric heater system to heat the reduction gas; stopping the providing the reduction gas; and providing a hydrogen gas or a hydrogen gas with added steam to remove carbon deposition from the electric heating elements of the electric heater system while continuing to heat the reduction gas such that the direct reduced iron production including carbon is not interrupted.

Abstract: A method and system for producing a direct reduced iron product, including: generating hot direct reduced iron in a shaft furnace; receiving the hot direct reduced iron in a feed-leg downstream of the shaft furnace; and adding carbon to the hot direct reduced iron in the feed-leg downstream of the shaft furnace to form the direct reduced iron product. The process may further include receiving and briquetting the hot direct reduced iron with the carbon added to form the direct reduced iron product. The process may further include receiving the hot direct reduced iron in an additional (optionally parallel) feed-leg downstream of the shaft furnace and adding other carbon (in a different amount) to the hot direct reduced iron in the additional feed-leg downstream of the shaft furnace to form an additional direct reduced iron product having a different carbon content, using the same stream of hot direct reduced iron.

Abstract: Direct reduction systems and methods utilize a direct reduction shaft furnace to reduce the iron oxide with a reduction gas received from a reduction/recycle gas loop. An electric gas heating system disposed in the reduction/recycle gas loop heats up the reduction gas with make-up hydrogen and/or natural gas before introducing to the shaft furnace. The gas heating system includes, in sequence, a primary gas heating unit utilizing a direct or indirect heating mechanism to first heat the reduction gas to a temperature below 600° C. or above 700° C. to avoid carbon deposition in the gas heating system and a secondary gas heating unit utilizing a direct heating mechanism to second heat the reduction gas to the temperature between 900° C. and 1100° C.

Abstract: A process for producing hot briquetted iron with increased solid carbonaceous material and/or flux includes: providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a hot briquette machine to produce hot briquetted iron; coupling a chute between a) a discharge exit of the shaft furnace for discharge of hot direct reduced iron and b) an entrance of the hot briquette machine; adding solid carbonaceous material and/or flux to the discharged hot direct reduced iron from the shaft furnace to produce a mixture of the discharged hot direct reduced iron and the solid carbonaceous material and/or flux before feeding to the hot briquette machine; and processing in the hot briquette machine to produce a product of hot briquetted iron with increased solid carbonaceous material content greater than about 3 weight percent and/or an increased flux content.

Abstract: A process for producing hot briquetted iron with increased solid carbonaceous material and/or flux includes: providing a shaft furnace of a direct reduction plant to reduce iron oxide with reducing gas; providing a hot briquette machine to produce hot briquetted iron; coupling a chute between a) a discharge exit of the shaft furnace for discharge of hot direct reduced iron and b) an entrance of the hot briquette machine; adding solid carbonaceous material and/or flux to the discharged hot direct reduced iron from the shaft furnace to produce a mixture of the discharged hot direct reduced iron and the solid carbonaceous material and/or flux before feeding to the hot briquette machine; and processing in the hot briquette machine to produce a product of hot briquetted iron with increased solid carbonaceous material content greater than about 3 weight percent and/or an increased flux content.

Abstract: Disclosed herein is a reduced iron production method enabling heat to be input well into reduced-iron raw materials on a hearth covering material in a reduction-melting furnace to improve the efficiency of treatment thereof. The reduced-iron raw materials are set on the hearth covering material through their falls and reduced on the hearth covering material. The hearth covering material is constituted by carbon materials each having a particle diameter of 5 mm or less. At least 7 mass % of the carbon materials have respective particle diameters each being 0.1 mm or less. This restrains the reduced-iron raw materials from embedment into the hearth covering material.

Abstract: Disclosed herein is a reduced iron production method enabling heat to be input well into reduced-iron raw materials on a hearth covering material in a reduction-melting furnace to improve the efficiency of treatment thereof. The reduced-iron raw materials are set on the hearth covering material through their falls and reduced on the hearth covering material. The hearth covering material is constituted by carbon materials each having a particle diameter of 5 mm or less. At least 7 mass % of the carbon materials have respective particle diameters each being 0.1 mm or less. This restrains the reduced-iron raw materials from embedment into the hearth covering material.

Abstract: The reduced iron manufacturing method of the present invention includes preparing an agglomerate by agglomerating a mixture containing an iron oxide-containing substance and a carbonaceous reducing agent, and preparing reduced iron by heating the agglomerate to reduce iron oxide in the agglomerate, characterized in that Expression (I) as follows is satisfied: Cfix×Xunder105/OFeO?51??(I) where OFeO is the mass percentage of oxygen contained in the iron oxide in the agglomerate, Cfix is the mass percentage of total fixed carbon contained in the agglomerate, and Xunder105 is the mass percentage of particles having a particle diameter of 105 ?m or less with respect to the total mass of particles configuring the carbonaceous reducing agent.

Abstract: A method and a device for charging a plurality of reduced iron raw materials into a traveling hearth reduction-melting furnace and treating the raw materials, allowing sufficient input of heat to the reduced iron raw materials on a hearth covering material to improve treatment efficiency are provided. The reduced iron raw materials are released downward from the lower surface of a ceiling of the reduction-melting furnace to be set on a hearth covering material on a hearth and reduced on the hearth covering material. The falling reduced iron raw materials are given a horizontal velocity having a direction equal to the travel direction of the hearth and being greater than the travel speed of the hearth to enable the reduced iron raw materials to roll in the same direction as the travel direction of the hearth after landing on the hearth covering material.

Abstract: The reduced iron manufacturing method of the present invention includes preparing an agglomerate by agglomerating a mixture containing an iron oxide-containing substance and a carbonaceous reducing agent, and preparing reduced iron by heating the agglomerate to reduce iron oxide in the agglomerate, characterized in that Expression (I) as follows is satisfied: Cfix×Xunder105/OFeO?51??(I) where OFeO is the mass percentage of oxygen contained in the iron oxide in the agglomerate, Cfix is the mass percentage of total fixed carbon contained in the agglomerate, and Xunder105 is the mass percentage of particles having a particle diameter of 105 ?m or less with respect to the total mass of particles configuring the carbonaceous reducing agent.

Abstract: A method and a device for charging a plurality of reduced iron raw materials into a traveling hearth reduction-melting furnace and treating the raw materials, allowing sufficient input of heat to the reduced iron raw materials on a hearth covering material to improve treatment efficiency are provided. The reduced iron raw materials are released downward from the lower surface of a ceiling of the reduction-melting furnace to be set on a hearth covering material on a hearth and reduced on the hearth covering material. The falling reduced iron raw materials are given a horizontal velocity having a direction equal to the travel direction of the hearth and being greater than the travel speed of the hearth to enable the reduced iron raw materials to roll in the same direction as the travel direction of the hearth after landing on the hearth covering material.

Abstract: Provided is a method for manufacturing iron nuggets by which reduced iron obtained by heating and reducing agglomerates, or iron nuggets obtained by melting and aggregating the reduced iron can be prevented from reoxidation inside a movable hearth heating furnace and quality of the reduced iron can be improved. The method involves charging and heating agglomerates including iron oxide and a carbonaceous reducing agent on a hearth of a movable hearth heating furnace, reducing and melting the iron oxide in the agglomerates, and then discharging obtained iron nuggets to the outside of the furnace and recovering the iron nuggets. The agglomerates have a coating layer, including a fluid carbonaceous material, on the surface.