A method for manufacturing molten iron by melting a cold iron source in an electric arc furnace having a carbonaceous material-injecting device. The method includes, in the carbonaceous material-injecting device, while a carbonaceous material is injected with a carrier gas through a central portion of the carbonaceous material-injecting device, injecting a fuel and a combustion-supporting gas through respective outer peripheral portions of the carbonaceous material-injecting device. The carbonaceous material injected through the central portion passes through a cylindrical combustion flame generated by a combustion reaction between the fuel and the combustion-supporting gas and is injected into molten slag and molten iron.

A method for producing a molten steel may provide: solid-state direct reduced iron containing 3.0% by mass or more of SiO.sub.2 and Al.sub.2O.sub.3 in total and 1.0% by mass or more of carbon, a ratio of a metallic iron to a total iron content contained in the solid-state direct reduced iron being 90% by mass or more, and an excess carbon content Cx to the carbon contained in the solid-state direct reduced iron being 0.2% by mass or more. Such methods may include: a slag separation including heating the solid-state direct reduced iron and melting it in an electric furnace without introducing oxygen to separate into a molten steel and a slag, and continuously discharging the slag, and a decarburization including blowing, in the electric furnace, a total amount of oxygen introduced into the electric furnace to the molten steel to decarburize the molten steel after the slag separation.

The invention relates to a method for extracting metal from metal-containing raw material in a batch process by using a direct current electric arc furnace (100) having one or more than one top electrode (125) and at least one bottom electrode (115), wherein the method comprises the following steps: adding the metal-containing raw material to the furnace (100), thereby obtaining a loaded bath, moving the top electrode(s) (125) onto the raw material, heating the loaded bath in a heating step by applying direct current through the top electrode(s) to provide an arc to melt the raw material, thereby obtaining molten metal (202), wherein an average voltage during the heating step is from 20 V to 110 V, and forming solid metal from the molten metal (202). The invention further relates to a direct current electric arc furnace, a system comprising a direct current electric arc furnace, and a solid metal obtainable by the method.

The present invention provides an electric furnace including: a cylindrical furnace wall; a furnace cover that is provided at an upper end of the furnace wall; and a furnace bottom that is provided at a lower end of the furnace wall and includes a deep bottom portion and a shallow bottom portion as a region having a height of 150 mm to 500 mm from a deepest point of the deep bottom portion, in which a slag pouring port into which molten slag or a solidified slag lump is capable of being poured from a slag transport container directly or through a tilting trough is provided, the slag pouring port overlaps the shallow bottom portion in a plan view, and the area ratio of the shallow bottom portion to the furnace bottom in a plan view is 5% to 40%.

A sealed feeder device utilized in an electric arc furnace (1), and a flue gas and temperature control method. The sealed feeder device comprises a sealed feeding chute (5) having an outlet sealedly communicating with a side wall of the electric arc furnace (1), and a material blocking sealed arc-shaped door (3) disposed in the sealed feeding chute (5). The material blocking sealed arc-shaped door (3) separates the sealed feeding chute (5) into a cold steel scrap storage chamber (18) and a material feeding and dedusting chamber (2), and is operated by a driving mechanism (34) to separate or connect the cold steel scrap storage chamber (18) and the material feeding and dedusting chamber (2). The method comprises: adopting the feeder device to divide the flue gas of the electric arc furnace (1) into two paths, and controlling, by a flue gas adjustment device (16), a ratio of a flue gas flow from a flow-splitting dust removal pipe (11) to that from a dust removal pipe (4) to obtain a required flue gas mixture temperature.

The present invention relates to a process and to a system for eliminating the expandability of steel-plant slag, which comprises a primary crusher (3) to reduce the fragments according to their granulometry; a magnetic separator (4) to remove metallic fragments bigger than a determined granulometry (5); a rotary dryer (6) to dry slag free from bigger metallic fragments; an impact mill (11) to disaggregate and fragment slag particles that are bigger than a predetermined granulometry; a classifier (12) for aero-classification and drag of fine and superfine particles; a cooler (17) for cooling slag particles bigger than a predetermined granulometry by means of heat exchange and removal of the fine and superfine particles that were not collected by the impact mill (11); a vibrating sieve (21) provided with two or more decks (23, 24, and 25) with screens of predetermined sizes; low-intensity magnetic separators (26, 27 and 28), with generation of non-magnetic slag fractions free from metallic iron and from iron monoxide, and of magnetic fractions composed by metallic iron and iron monoxide; and low-intensity magnetic separators (35, 36 and 37) to reprocess the magnetic fractions with generation of concentrate with high metallic iron contents and a product with high concentration of iron monoxide.

A method of charging a pre-packaged charge in a metallurgical or refining furnace includes providing a disposable metal container having at least one attachment member and forming a pre-packaged charge by loading scrap material into the metal container. The method also includes releasably coupling the at least one attachment member of the container to a lifting device, and then de-coupling the pre-packaged charge from the lifting device so that the combination of the scrap material and the disposable metal container are charged in the furnace.

The present invention belongs to the technical field of metallurgy, and discloses a horizontal continuous feeding preheating device and an enhanced preheating method therefor. The scheme comprises that two dust removal ports are arranged at the front and rear parts of a horizontal continuous feeding preheating duct, and the horizontal continuous feeding preheating duct is divided into an enhanced preheating area and a flue gas preheating area by the two dust removal ports arranged at the front and rear parts of the horizontal continuous feeding preheating duct; burners are installed in the enhanced preheating area, and the two dust removal ports are connected with a flue gas adjusting distributor respectively by a flue gas pipeline the steel scrap preheating efficiency of the burners and electric arc furnace flue gas is increased by controlling the flow rate and temperature of mixed flue gas.

A method for operating an electric arc furnace having at least one electrode, the method including the following steps: introducing material that is to be melted in the form of an actual mass flow into the electric arc furnace and feeding electrical energy via at least one electrode into the electric arc furnace in order to melt the introduced material depending on a previously determined, necessary electrical energy input. The necessary electrical energy input into the arc furnace is determined depending on the mass flow input into the furnace.

Methods and systems for managing a heating process are disclosed. An example method can comprise removing a first portion of a material from a vessel and measuring a first parameter of a second portion of the material in the vessel. The second portion of the material can remain in the vessel after the removal of the first portion. The method can comprise, determining a volume of the second portion of the material based on the first parameter, updating a second parameter based on the volume, and performing a process based on the updated second parameter.