Abstract: A method of decarburizing a molten alloy may generally comprise injecting a first gas comprising at least one of argon, carbon dioxide, and oxygen through a first fluid-conducting portion of a tuyere into the molten alloy below the surface of the molten alloy, and injecting a second gas comprising at least one of argon and carbon dioxide through a second fluid-conducting portion of the tuyere into the molten alloy below the surface of the molten alloy. The tuyere may comprise an inner portion concentrically aligned within an outer portion to define an annulus therebetween. The first gas may be injected through the inner portion, and the second gas may be injected through the annulus.

Abstract: A direct smelting process for producing molten metal from a metalliferous feed material in a direct smelting vessel is disclosed. The process includes using a stream of off-gas from the vessel as a fuel gas in (i) stoves for generating a hot blast of air or oxygen-enriched air for the process and (ii) a waste heat recovery apparatus for generating steam for the process. The process also includes controlling pressure in the vessel by controlling pressure in the off-gas stream while the process is producing molten metal.

Abstract: A method of cold starting a molten bath-based direct smelting process for producing molten iron in a vessel (3) is disclosed. The method includes a step of preheating the vessel before supplying solid feed materials into the vessel. The method also includes a subsequent step of supplying an oxygen-containing gas and solid feed materials including material for forming slag, iron-containing feed material, and carbonaceous material into the vessel and generating heat and forming a bath of molten material that includes molten iron and molten slag in the vessel. This step includes supplying feed materials to promote formation of molten slag over molten iron in an early stage of developing the molten bath.

Abstract: A process for producing iron metal and slag by smelting iron-containing source material, having iron present as oxide and/or a partially metalized state, in a reactor containing a molten bath comprising or having a slag phase, utilises injection of fuel/reductant and oxygen-containing gas into the slag, by at least one top-submerged lance, to generate heating and reducing conditions in at least one reducing region in the bath. The source material is fed to the reactor, together with additional reductant and with flux, at or adjacent to the at least one reducing region, to subject the source material to smelting reduction which generates combustion gases comprising CO and H2. The rates of injection of the oxygen-containing gas and fuel/reductant by said at least one lance are controlled to achieve required, sufficient reducing conditions; and, in the reactor above the bath, the combustion gases generated by the smelting are post-combusted.

Abstract: A method for reducing the chromium content from a metallurgical slag, in which the slag is charged onto an iron bath in the liquid state and the reduction of Cr is effected by the iron bath having a C content of 2 to 4% by weight, wherein a) the Cr-containing slag having a Cr content of 2 to 20% by weight is charged onto an iron bath having a C content of below 1% by weight, whereupon b) the carbon content of the iron bath is raised to about 2 to 4% by weight by the addition of carbon carriers at the simultaneous supply of energy, c) the liquid slag having a Cr content of about 0.1% by weight is tapped after the reduction of Cr, d) a cooling agent, preferably scrap, is added to the iron melt and the C content of the melt is lowered to below 1% by weight, and e) a portion of the Cr-containing melt is tapped in the liquid state, while the remaining portion is left in the converter in the liquid state for the treatment of the subsequent melt.

Abstract: A molten bath-based direct smelting process for producing ferrous metal from a ferrous feed material is disclosed. The process is characterised by injecting pro-heated air downwardly into metallurgical vessel at an angle of 20 to 90° C. relative to a horizontal axis and at a temperature of 800-1400 ° C. and at a velocity of 200-600 m/s via at least one lance (27) . This step forces molten material in the region of a lower end of the lance away from the lance and forming a “free”space around the lower end of the lance that has a concentration of molten material that is lower than the molten material concentration in the raised bath. The process is further characterised in that the lance is located so that: (i) the lance extends into the vessel a distance that is at least the outer diameter of he lover end of the lance; and (ii) the lower end of the lance is at least 3 times the outer diameter of the lower end of the lance above a quiescent surface of the molt bath.

Abstract: A molten bath-based direct smelting process for producing ferrous metal from a ferrous feed material is disclosed. The process is characterised by injecting pre-heated air downwardly into metallurgical vessel at an angle of 20 to 90° C. relative to a horizontal axis and at a temperature of 800-1400° C. and at a velocity of 200-600 m/s via at least one lance (27). This step forces molten material in the region of a lower end of the lance away from the lance and forming a “free” space around the lower end of the lance that has a concentration of molten material that is lower than the molten material concentration in the raised bath. The process is further characterised in that the lance is located so that: (i) the lance extends into the vessel a distance that is at least the outer diameter of the lower end of the lance; and (ii) the lower end of the lance is at least 3 times the outer diameter of the lower end of the lance above a quiescent surface of the molten bath.

Abstract: A process for desulfurizing a molten iron alloy in which a desulfurizing agent is applied to the molten iron alloy under agitation. Concurrently, a gas containing a hydrocarbon gas is blown onto the bath surface of the molten iron alloy, or a substance generating a hydrocarbon gas is added to the bath surface.

Abstract: A continuous process for recovering vanadium values from petroleum coke is disclosed. A vanadium containing coke is charged to a molten metal bath to which oxygen containing gas is added in an amount sufficient to heat balance the process and produce off gas. The carbon in the coke dissolves in the molten metal bath as does the vanadium content of the coke. A majority, and preferably all, of the net addition of vanadium to the process is removed in the form of “dust” from the molten metal bath.

Abstract: A process for the recovery of vanadium from a petroleum coke or heavy hydrocarbon feed comprising dissolving the feed in a molten metal bath to which oxygen containing gas is added to maintain heat balance and bum off carbon. Preferably the feed is added via a high pressure nozzle as a coke/steam mixture discharged down into a molten metal bath. Preferably the net gas make from the molten metal reactor is quenched and/or cooled to permit dust recovery, with recycle of dust to the molten metal reactor. An iron/vanadium product is withdrawn from the molten metal reactor as a product.

Abstract: In a process for separating tin as well as, if required, copper from scrap melts, in particular, tinplate melts or metallic melts as formed in the working up of waste or metal-oxide-containing combustion residues, the carbon content of the melt is adjusted to 3 to 4.2% by weight and hot wind, oxygen or air enriched with oxygen is locally blown on partial regions of the surface of the melt bath, whereby SnO is discharged, via the gaseous phase, from the redox-gradient-exhibiting zone formed between the carbon-rich bath and the iron oxides produced by top-blowing.

Abstract: A process for blowing oxygen-containing gas, with and without solid material, on a metal melt in a metallurgical vessel, a process for generating a burner flame and corresponding devices. The inventive process and lance suitable for such process provides, without structural conversion and by a simple design, various different process steps in the treatment of metal melts in a metallurgical vessel while increasing the insertion rates of the individual media. This is accomplished using a multifunctional lance in which the process of blowing oxygen with and without solids, and the generation of a burner flame may be performed independently from one another. The individual supply lines are connected in a corresponding manner depending on the respective process step. In the process for blowing oxygen-containing gas, vibrations are excited in the gas flow in a relatively simple manner.

Abstract: A method of decarburizing refining molten steel containing Cr in such a manner that oxygen gas, inert gas or a mixture of inert gas and oxygen gas is blown to the surface of bath of molten steel containing Cr in a refining chamber and to a position below the surface of the steel bath. Inert gas is blown to the surface of the steel bath, and oxygen gas, the inert gas or a mixture of oxygen gas and inert gas is blown below the surface of the steel bath in a portion of or all of an overall period in which the concentration of C in the molten steel is in a range of 1 wt % and 0.05 wt %. Slag and molten steel are stirred so as to cause Cr.sub.2 O.sub.3 in the slag and C in the molten steel to positively take part in a reaction represented by expression (1) below:Cr.sub.2 O.sub.3 +3C.fwdarw.

Abstract: The invention relates to a process for the desulphurization treatment of a pig iron melt in a container. The characterizing feature of the invention is that the treatment is performed in three phases:In the initial phase such solids are injected that deoxidize the initial slag and increase its basicity and also produce a circulatory movement of the melt and form a basic deoxidized cover slag. In the middle phase the desulphurizing agent is injected for the main desulphurization and in the final phase such solids are injected that purify the melt and produce a final desulphurization and also so influence the desulphurization slag formed that its content of iron granules is low.

Abstract: A method of in-bath smelting reduction comprises the step of selectively supplying powder materials into a gas upflow region or a gas downflow region within a furnace during the time that oxygen-containing gas is concurrently being blown into the furnace from a top lance. Also disclosed is an in-bath smelting reduction furnace for carrying out the method.

Abstract: A method for manufacturing molten pig iron is disclosed which comprises:forming a packed bed of coke in a vertical furnace having a charging port in an upper portion thereof for charging raw materials and discharging gases, one or more primary tuyeres in its lower portion, and one or more secondary tuyeres in a wall of the furnace at a level above the primary tuyere, the packed bed of coke extending higher than the level of the primary tuyere;forming a packed bed of scrap and iron ore atop the packed bed of coke to a level which extends above the secondary tuyere; andblowing an oxidizing gas through the primary tuyere and the secondary tuyere to melt and reduce the scrap iron and iron ore.

Abstract: A method of operating an in-bath smelting reduction furnace comprises the step of forming a slag zone in an in-bath smelting reduction furnace supplied with oxygen through a top lance and with agitation gas by bottom bubbling through tuyeres below the metal bath surface, and the step of controlling the carbon material supply rate, the oxygen supply rate and the ore supply rate so as to maintain the apparent density of the slag within a prescribed range.

Abstract: A method for economically manufacturing an iron-boron-silicon alloy through simple steps, which comprises the steps of: adding a boron raw material and a carbonaceous reducing agent to a molten iron received in a vessel; blowing oxygen gas into the molten iron to reduce the boron raw material in the molten iron by means of the carbonaceous reducing agent to prepare a boron-containing molten iron; continuing the blowing of oxygen gas to decarburize the boron-containing molten iron until the carbon content in the boron-containing molten iron decreases to up to 0.2 wt. %; and adding at least one of silicon and ferrosilicon to the boron-containing molten iron while stirring the boron-containing molten iron, thereby manufacturing an iron-boron-silicon alloy.

Abstract: Described herein is a smelting reduction process for smelting and reducing an iron oxide material by introducing same into a smelting reduction furnace together with a solid carbonaceous material, a fluxing agent and an oxygen-containing gas, process comprising: subjecting part or all of the solid carbonaceous material to primary combustion using an oxygen-containing gas with an oxygen content corresponding to a theoretical air ratio of 0.4 to 0.9: separating the resulting reducing gas from combustion residue of the solid carbonaceous material; and introducing the reducing gas into a smelting reduction furnace to effect secondary combustion with supply of a separately introduced oxygen-containing gas for smelting and reducing said iron material.

Abstract: The present invention relates to a new steelmaking process and apparatus which operates on an intermittent basis where several cycles composed of reducing and oxidizing periods are performed to create sufficient energy for melting of solid metallic charge, i.e., sponge iron, scrap, iron ore. During the reducing period, oxygen and carbonaceous material are injected through the vessel bottom thus attaining both carburization of a steam of the melt and generation of CO+H.sub.2 rich gas, and when the dissolved carbon of the melt is in the range of 3%-4%, conditions are then changed to the oxidizing period where solid metallic charge is added initially while oxygen injection is maintained, and until the solid charge has been melted, thus generating a stream of CO+CO.sub.2 gas rich in CO. In addition, other fluids and solids participate in the process, i.e., nitrogen, hydrocarbons, fluxes, and are used according to the appropriate period of the process.

Abstract: In a batch production of steel, a charge including solid scrap is loaded into an oxygen steel converter, the scrap is melted and the charge is refined in the converter by means of an oxygen blowing lance inserted into the converter through the converter mouth. To enable larger quantities, i.e. over 30% of scrap to be used, the solid scrap is heated by combustion of fuel in the converter using the oxygen blowing lance whose outlet is, at least initially, below the top level of the scrap in the converter, so that the combustion gases formed by the combustion of the fuel pass upwardly through the scrap.

Abstract: Disclosed are an improved method of refining steel and an apparatus for practicing the method.The refining method comprises, basically, carrying out the refining, particularly, decarburization, while stirring molten steel in the refining furnace by injecting gas thereinto, while supplying heat with a burner installed at the top of the furnace to the molten steel. According to this method, it is possible to start at an initial carbon content of the moltend steel lower than that of known AOD process, and complete the refining in a curtailed period of time and with a decreased oxidation loss of Cr. Thus, damage of refractory materials of the furnace is reduced, and the amount of Si necessary for reducing Cr-oxides in the latter stage of the refining is also reduced.Oxygen for the decarburization is supplied usually in the form of gas, but can be supplied from a solid oxygen source.

Abstract: A process of production of chromium containing molten iron generally comprises two steps. In a first step, top and bottom-blown reduction for reducing chromium is performed with charging carbon containing material and slag forming agent from the top of a converter for melting stainless scrap and for rising temperature of molten iron bath. In a second step which is performed subsequently to the first step, top and bottom-blown injection with charging chromium oxide and carbon from the top of the converter for reduction of chromium.