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 and an industrial plant for separating a waste material comprises at least one metal and at least one organic material. A separated fraction of the waste material is provisioned which is isolated from the waste material in the course of a mechanical preparation operation. The separated fraction comprises briquettes produced from the waste material, and optionally a coarse fraction of the waste material or of another waste material. A reactor is charged with the separated fraction and gas containing oxygen is introduced into the reactor and the separated fraction is combusted in an incomplete combustion process. The separated fraction is melted into a liquid slag phase and into a liquid metal-containing phase. The slag phase and/or the metal-containing phase are poured off from the reactor.

The invention relates to a mixture to be introduced into the slag located on a metal melt in iron and steel metallurgy, the use of such a mixture, and a method for conditioning a slag located on a metal melt in a metallurgical vessel, for example in a converter, in an electric arc furnace or in a ladle, in iron and steel metallurgy.

Composite particles are used in combination with ore particles in an ore-refining or purification process, such as in a steel- or iron-making process. The composite particles comprise a core, which may be an aggregate of limestone, dolomite, or another ore particle. The core is surrounded by a coating layer of a metal dust and a binder. The metal dust may be iron oxide dust, which, along with limestone, is prevalent in the iron smelting process anyway. In this way, the composite particles help to recycle otherwise wasted and hazardous iron dust. The binder may be mineral clay such as bentonite, montmorillonite or kaolinite, and may comprise about 2-10% by weight of the particle.

A charged material containing alloy iron of at least one of ferrochrome containing metallic Si or ferrosilicon, and unreduced slag containing Cr oxide generated by oxidative refining, is charged into an electric furnace as a mixture in which a mass ratio of a metallic Si amount to a Cr oxide amount is from 0.30 to 0.40, and a C concentration is in a range of from 2.0% by mass to a saturation concentration, and molten iron containing Cr obtained due to the Cr oxide undergoing reduction processing is produced, such that, when the charged material is heated and melted in the electric furnace, an attainment temperature is set to from 1400° C. to 1700° C., a maximum average heating rate in any 80° C. interval from 1300° C. to the attainment temperature is set to 15.0° C./min or less, and a minimum average heating rate in any 80° C. interval from 1300° C. to the attainment temperature is set to 3.0° C./min or greater.

A charged material containing a metal raw material of at least one of ferrochromium containing metal Si or ferrosilicon and unreduced slag containing Cr oxide generated by oxidation refining is charged into an AC electric furnace including three electrodes, a mass ratio of a metal Si amount to a Cr oxide amount being from 0.30 to 0.40, and a C concentration being from 2.0% by mass to a saturation concentration, and operation is performed under a condition where a diameter PCD (m) of a circle passing through the centers of the three electrodes viewed in a plan view from a central axis direction of the electric furnace, an average electrode height H.sub.e (m) that is a vertical distance from a tip of each electrode to a molten metal surface, a furnace inner diameter D.sub.f (m), a molten slag thickness H.sub.s (m), a spreading diameter D.sub.arc (m) of an arc on the molten metal surface, and a deflection angle θ (deg) of the arc satisfy the following relationships to produce molten iron containing Cr.

D.sub.arc=PCD+2H.sub.e.Math.tan θ

θ=52.5−75.Math.(PCD/D.sub.f)

0.22≤D.sub.arc/D.sub.f≤0.30

0.35≤H.sub.e/H.sub.s≤1.50

A method for manufacturing a steel ingot in a casting arrangement (100) comprising a vacuum vessel (110); an ingot mold (120) arranged within the vacuum vessel and a stirrer (130) arranged to stir liquid steel in the ingot mold, comprising: -providing (1000) a liquid steel melt; filling (2000) the ingot mold (100) with the liquid steel melt; applying (3000) a reduced pressure within the vacuum vessel (110); allowing the liquid steel melt to solidify into an ingot; allowing the liquid steel melt to solidify under stirring within the ingot mold at a reduced pressure during solidification of the steel melt; wherein, the liquid steel melt comprises a predetermined amount of carbon and; incidental impurity elements in the form of oxides, wherein during stirring the oxides are reduced by carbothermic reaction in which oxygen in the oxides and carbon in the steel melt form carbon-monoxide.

Disclosed is a slag discharging method in a process of producing ultra-low phosphorus steel, which relates to the technical field of iron and steel smelting, and in which molten steel is mixed with lime first to produce basic slag; then converting is performed with oxygen to increase the oxidizability of the basic slag; and a carbon-containing reducing agent is finally added, so that in the process that the carbon is oxidized to release a large amount of carbon monoxide gas, phosphates are captured, and the basic slag is rapidly foamed and overflows from the opening of the steel ladle, so that conditions are no longer available for rephosphorization. Also disclosed is a method for producing ultra-low phosphorus steel, which includes the above-described slag discharging method in a process of producing ultra-low phosphorus steel, and refining and ingotting after slag discharge.

A method for producing chromium-containing molten steel from a raw material including a chromium-containing raw material includes a first step in which a slag basicity before rough decarburization by oxygen blowing is adjusted to be not less than 1.5 and not more than 3.0, a slag basicity after rough decarburization by oxygen blowing is adjusted to be not less than 2.0 and not more than 3.5, and then tapping is performed while slag containing a chromium oxide generated by the oxygen blowing is made to remain in the furnace, and a second step in which the slag containing a chromium oxide made to remain is reduced by using a carbon source or a metal source newly added into the same furnace so that chromium is recovered into molten steel. The slag basicity is determined by dividing a CaO concentration by an SiO.sub.2 concentration on a mass basis in the slag.

A production apparatus and method for electric arc furnace steelmaking with a fully continuous ultra-short process are provided. A continuous adding, melting, smelting and continuous casting of a metal material are integrated, and a metallurgy process is completed in a flowing of a molten steel, to realize a continuous production of ingot blanks. The production apparatus includes four operation sites of an electric arc furnace for melting and primary refining, a sealed tapping chute for molten steel flowing, a refinement storage bed for molten-steel desulfurization and alloying and a conticaster for continuous casting A material flow, an energy flow and a time stream in the four operation sites are in a dynamic equilibrium. The production apparatus and method realize a molten-steel casting is started within 120 minutes after the metal material is started to be continuously added, and an uninterrupted continuous production is maintained for above 80 hours.