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.

A method determines the consumption of electrode material during the operation of an electric furnace, particularly an arc furnace for producing steel. The method determines a weight of an electrode column, which is arranged in the electric furnace or is to be introduced into the electric furnace, using a weighing device. A device for determining the consumption of electrode material of an electric furnace, particularly an arc furnace for producing steel, is provided for performing the method. The device contains a weighing device for determining the weight of at least one electrode column which is arranged in the electric furnace or is to be introduced into the electric furnace, wherein the weighing device is integrated in an operating device of a system containing the electric furnace. Vibration conditions of the electrode column during operation of the electric furnace can also be determined with the method and with the device.

A direct current plasma arc furnace includes a tank having a crucible delimiting a chamber to receive material to be melted and/or treated; refractory walls surrounding the crucible outer surface; a metallic frame covering the refractory walls; and a heating system for heating the received material. The heating system includes two electrodes acting as cathode and anode, respectively, wherein the first electrode is a movable electrode to project vertically into the chamber. The crucible is part of an anode system also having the second electrode and at least one part connecting the crucible and second electrode. The crucible receives and holds material to be melted and/or treated and provides electric conduction for the flow of current to heat the material, such that the voltage potential difference between the cathode and any point of the crucible surface defined to be in contact with the material is the same.

Disclosed is a method for smelting low nitrogen steel by using an electric furnace. The smelting is performed using a dual-shell electric furnace, The dual-shell electric furnace has two furnace shells. An arc power system of the dual-shell electric furnace is used for alternatively electric heating on the two furnace shells, wherein when one of the two furnace shells is subjected to electric heating, feeding, sealing of a molten pool and blowing of a combustion medium and oxygen are sequentially carried out in the other furnace shell to start smelting. When the temperature of molten steel in the furnace shell subjected to electric heating reaches a target temperature, electric heating starts to be carried out on the other furnace shell. The method for efficiently smelting the low nitrogen steel by using the electric furnace of the disclosure, not only can shorten the smelting period and improve the throughput of a production line of an electric furnace, but also smelt low nitrogen steel to satisfy the requirements of the market on high-end steel. in addition, the method for efficiently smelting the low nitrogen steel by using the electric furnace of the disclosure can reduce the discharge of dust and smoke, thereby protecting the environment.

The invention relates to a process for producing low-nitrogen crude steel. This process includes melting directly reduced iron and/or scrap in a melting furnace with arc resistance heating to give a metallic melt and a slag. The metallic melt is removed from the melting furnace and used to charge a converter. The metallic melt is refined in the converter to give liquid crude steel. The liquid crude steel is tapped having a nitrogen content [N] of not more than 50 ppm, especially of not more than 30 ppm.

A metal product manufacturing device is provided to remove, with higher accuracy, impurities from a molten metal of a non-ferrous metal or another metal containing the impurities, obtain the molten metal having higher purity, and obtain a high-purity non-metal product or another metal product from the high-purity molten metal.

Proposed is a method for efficiently desulfurizing molten metal in a short time without passing an excessive current when applying a potential difference between slag and metal. Using a direct-current power source, this method for desulfurizing molten metal applies a potential difference between molten slag and molten metal through electrodes, of which one electrode contacting the molten metal serves as a negative electrode and the other electrode contacting only the molten slag serves as a positive electrode. An applied current density J.sub.a is determined according to an equilibrated S concentration [S].sub.e0 before application of a potential difference such that an equilibrated S concentration [S].sub.ea when a potential difference is applied becomes equal to or lower than a target S concentration [S].sub.ft.

An electrode includes a network of compressed interconnected nanostructured carbon particles such as carbon nanotubes. Some nanostructured carbon particles of the network are in electrical contact with adjacent nanostructured carbon particles. Electrodes may be used in various devices, such as capacitors, electric arc furnaces, batteries, etc. A method of producing an electrode includes confining a mass of nanostructured carbon particles and densifying the confined mass of nanostructured carbon particles to form a cohesive body with sufficient contacts between adjacent nanostructured carbon particles to provide an electrical path between at least two remote points of the cohesive body. The electrodes may be sintered to induce covalent bonding between the nanostructured carbon particles at contact points to further enhance the mechanical and electrical properties of the electrodes.

A method of producing steel by charging a furnace with scrap metal and agglomerated oxy-carbon material into a workspace of a furnace, to reduce specific electricity consumption when melting. Increasing the iron output quantity by inputting electric energy, fuel, a carburizer, a flux and gaseous oxygen, using electric arc melting with decarburization of a metal bath, and releasing metal and slag from the furnace. Prior to melting, a portion of the material is loaded with a first portion of the metal charge into the central zone of the furnace, and the remaining material into the melted charge during melting 0.5-10 kg/min per 1 megavolt-ampere of electric arc transformer power. The oxy-carbon material size is between 5 and 80 millimeters.

The invention provides a maraging steel production method in which an oxide is added during an Mg oxide formation step, the production method including: the Mg oxide formation step in which Mg is added to molten steel and MgO is formed in the molten steel, during primary melting; a consumable electrode production step in which, after the Mg oxide formation step, the molten steel is solidified and a consumable electrode having residual MgO is obtained; and a vacuum arc re-melting step in which the consumable electrode is used and vacuum arc re-melting is performed.