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.

A device and a method for continuous desulphurisation of liquid iron provided by a blast furnace process or a direct reduction process.

The invention relates to granules composed of agglomerated reactive bulk material and a binder matrix, the binder matrix comprising as binder an organic or inorganic salt.

The invention relates to granules composed of agglomerated reactive bulk material and a binder matrix, the binder matrix comprising as binder an organic or inorganic salt.

A method for preparing low-cost clean steel includes steps of: preliminarily desulfurizing iron melt: preliminarily desulfurizing in an iron melt channel during blast furnace tapping and during iron folding in an iron folding room, adding a desulfurizing ball into the iron melt during the blast furnace tapping or the iron folding; dephosphorizing and controlling sulfur: dephosphorizing and controlling sulfur during converter steelmaking, in such a manner that P0.014% and S0.004% during tapping; rapidly dephosphorizing by slag-forming: rapidly dephosphorizing by slag-forming during converter tapping, at a converter end point, controlling a C content at 0.020.10%, adding a dephosphorizing ball through an alloy chute during the converter tapping, blowing argon and stirring at the same time; purifying steel melt during RH refining: adding a purifying ball at a late stage of the RH refining when a vacuum degree is at 66.7500 Pa; and continuously casting with whole-process protection.

A process and a device are provided that avoid the problems expressed earlier in order to produce a current of alloy particles at temperatures above 400 C. that will ultimately be used to alloy or chemically treat liquid metal streams. The invention that is presented is composed of a chamber heated by one or more gas burners, where a current of alloy particles with the pre-established massic or volumetric flow is input either manually or via the use of a gravimetric or volumetric dosing device that operates at room temperature located in an area above the chamber. These particles are heated by radiation from the walls of the chamber and by the radiation and convection of the flames of the burners that sweep them along during their flight inside the device for the time that they remain inside the chamber. As result of the use of the proposed device and the process, during which a great amount of energy is received during their passage through the device, the alloy particles reach the required temperature prior to their incorporation into a metallic current.

A method for manufacturing pig iron in an electrical smelting furnace including a vessel, the method including the following successive steps: loading DRI product in the vessel, melting the DRI product to form a pig iron layer topped by a slag layer and, tapping the pig iron into a ladle, and adding a carbon containing material directly in the pig iron in the runner of at least one of the smelting furnace tap holes. It also deals with the manufacturing of steel from the pig iron and the associated electrical smelting furnace.