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 steel board for polar marine engineering and a preparation method therefor. According to weight percentage, the components of the steel board are: C: 0.06-0.09%, Si: 0.20-0.35%, Mn: 1.48-1.63%, Nb: 0.020%-0.035%, Ti: 0.010%-0.020%, V: 0.020%-0.035%, Ni: 0.08%-0.17%, Als: 0.015%-0.040%, P: ≤0.013% and S: ≤0.005%. The preparation method for the steel board comprises: pre-refining, refining and casting to obtain a cast billet, and the slowly cooling down same. The slowly cooled billet is heated and then rolled out to obtain the steel board; and the steel board is cooled down and ready. The steel has an excellent comprehensive performance in terms of having high strength and low temperature resistance, being easy to weld and corrosion proof, and the steel has good low-temperature aging impact toughness.

The present disclosure provides a method of making low carbon steel. The method includes tapping the liquid steel out of a primary steelmaking furnace. Deoxidizing the liquid steel. Transferring the deoxidized liquid steel to a ladle metallurgy furnace. Removing sulfur at the ladle metallurgy furnace. Adding fluxes and arcing the liquid steel to prevent sulfur reversion. Transferring the liquid steel from the ladle metallurgy furnace to an RH degasser for carbon removal. The removal of oxygen and sulfur prior to transferring the liquid steel to the RH degasser facilitates nitrogen removal and prevents carbon pick up during the step sulfur removal.

An inoculant for the manufacture of cast iron with spheroidal graphite is disclosed, the inoculant has a particulate ferrosilicon alloy having between 40 and 80% by weight of Si; 0.02-8% by weight of Ca; 0-5% by weight of Sr; 0-12% by weight of Ba; 0-15% by weight of rare earth metal; 0-5% by weight of Mg; 0.05-5% by weight of Al; 0-10% by weight of Mn; 0-10% by weight of Ti; 0-10 by weight of Zr; the balance being Fe and incidental impurities in the ordinary amount, wherein the inoculant additionally contains, by weight, based on the total weight of inoculant: 0.1 to 15% of particulate Sb.sub.2S.sub.3, and optionally between 0.1 and 15% of particulate Bi.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Sb.sub.2O.sub.3, and/or between 0.1 and 15% of particulate Bi.sub.2S.sub.3, and/or between 0.1 and 5% of one or more of particulate Fe.sub.3O.sub.4, Fe.sub.2O.sub.3, FeO, or a mixture thereof, and/or between 0.1 and 5% of one or more of particulate FeS, FeS.sub.2, Fe.sub.3S.sub.4, or a mixture thereof, a method for producing such inoculant and use of such inoculant.

There is provided a method of dynamic control for a bottom blowing O.sub.2—CO.sub.2—CaO converter steelmaking process. In the process, O.sub.2 is adopted as a top blowing gas, a mixed gas O.sub.2+CO.sub.2 is adopted as a bottom blowing carrier gas to inject lime powders into the converter from a bottom blowing tuyere. The ingredients of the molten steel in the converter steelmaking process are predicted based on the conservation of matter, in combination with the ingredient data of charged molten iron, the ingredient data of the converter gas in the converter blowing process, and working conditions of the bottom blowing device. The top blowing oxygen amount, the bottom blowing gas ratio and the flow rate of lime powder are dynamically adjusted stage by stage according to requirements for target ingredients at the end point of blowing.

The invention relates to a process for injecting particulate material into a liquid metal bath wherein the liquid metal bath contains species to be oxidized, wherein the particulate material is carried to the liquid bath by means of a first gas stream. The solids injection rate is controlled such that the liquid bath temperature and/or the evolution of the liquid bath temperature is maintained within a pre-defined temperature range and the penetration depth of the first gas stream into the liquid bath is controlled by adjusting the flow of the first gas stream. At least one second gas stream is injected into the liquid, wherein the first and the second gas streams are an oxidizing gas, in particular oxygen, and the sum of the gas flows of the first and the second gas streams is determined based on the mass of the species to be oxidized and on the desired time for oxidizing the mass of the species.

A decarburization refining method for molten steel under reduced pressure. The method includes an oxygen-blowing decarburization and a rimmed decarburization. Using operation data taken at a time when oxygen-blowing decarburization is started and a time when oxygen-blowing decarburization is ended, an amount of carbon removed while the oxygen-blowing decarburization is performed is estimated. Based on the estimated amount of carbon removed, a carbon concentration in molten steel at a time when the rimmed decarburization is started is estimated. Using the estimated value as the carbon concentration in molten steel at the time when the rimmed decarburization is started, a change over time in the carbon concentration in molten steel while the rimmed decarburization is performed is calculated. Based on the calculated change over time in the carbon concentration in molten steel while the rimmed decarburization is performed, a determination is made about a time when the rimmed decarburization is ended.

An oxygen blowing lance comprising: a lance body including an oxygen conduit and cooling water inlet and outlet conduits surrounding said oxygen conduit; a lance head connected to said lance body and comprising a nozzle body, said nozzle body including a central strut having bore hole, a plurality of nozzles arranged about said central strut, and a plurality of cooling chambers arranged about said central strut, wherein said plurality of nozzles are in fluid communication with said oxygen conduit for discharging oxygen from said oxygen conduit onto a metal bath in a converter vessel, and wherein said plurality of cooling chambers are in fluid communication with said cooling water inlet and outlet conduits; a temperature probe or camera assembly received in said bore hole for monitoring the temperature of said lance head or molten heat in which the lance is inserted; signal lines connected to said temperature probe for conveying signals from said temperature probe whereby operation of said blowing lance is regulated in response to said signals; and a protective pipe pressurized with a gas disposed in the bore and surrounding said temperature probe assembly and the signal lines.

An oxygen blowing lance comprising: a lance body including an oxygen conduit and cooling water inlet and outlet conduits surrounding said oxygen conduit; a lance head connected to said lance body and comprising a nozzle body, said nozzle body including a central strut having bore hole, a plurality of nozzles arranged about said central strut, and a plurality of cooling chambers arranged about said central strut, wherein said plurality of nozzles are in fluid communication with said oxygen conduit for discharging oxygen from said oxygen conduit onto a metal bath in a converter vessel, and wherein said plurality of cooling chambers are in fluid communication with said cooling water inlet and outlet conduits; a temperature probe or camera assembly received in said bore hole for monitoring the temperature of said lance head or molten heat in which the lance is inserted; signal lines connected to said temperature probe for conveying signals from said temperature probe whereby operation of said blowing lance is regulated in response to said signals; and a protective pipe pressurized with a gas disposed in the bore and surrounding said temperature probe assembly and the signal lines.

A method for mitigating the buildup of direct reduced iron (DRI) clusters on the walls of a direct reduction (DR) furnace, comprising: injecting one or more of lime, dolomite, and another anti-sticking agent into a charge disposed within a reduction zone of the DR furnace, wherein the one or more of lime, dolomite, and another anti-sticking agent is injected into the charge by one or more of: (1) injecting the one or more of lime, dolomite, and another anti-sticking agent into a bustle gas stream upstream of a bustle of the DR furnace; (2) injecting the one or more of lime, dolomite, and another anti-sticking agent into the bustle gas stream in the bustle of the DR furnace; (3) injecting the one or more of lime, dolomite, and another anti-sticking agent into the bustle gas stream through a pipe collocated with a bustle gas port through which the bustle gas stream is introduced into the DR furnace; and (4) injecting the one or more of lime, dolomite, and another anti-sticking agent directly into the reduction zone of the DR furnace separate from the bustle gas stream.