Abstract: A converter bottom blowing system comprises a first gas source connected in parallel with a lime powder silo, a lime powder blowing tank and a first injector, where a first cut-off valve is arranged between the lime powder blowing tank and the first injector; a second gas source connected in parallel with the biochar powder silo, the biochar powder blowing tank and the second injector, where a second cut-off valve is arranged between the biochar powder blowing tank and the second injector; a converter, where a plurality of bottom blowing lances are arrayed at a bottom of a converter, the bottom blowing lances are connected with the first injector and the second injector through a three-way valve, a third cut-off valve is arranged between the first injector and the three-way valve, and a fourth cut-off valve is arranged between the second injector and the three-way valve.

Abstract: In a method for oxygen-blowing refining of molten iron, an oxygen-containing gas as a main supply gas is supplied from an inlet side of a blowing nozzle for the oxygen-containing gas passing through an outer shell of the top-blowing lance and blown from the blowing nozzle while a control gas is jetted toward inside of the blowing nozzle for at least part of a period of the oxygen-blowing refining from a spout arranged in a side face of the nozzle at a site where the cross-sectional area of the nozzle minimum takes the minimum in the axial direction of the nozzle or a neighborhood thereof so that at least part of the spout exists in each space formed by dividing into two portions by an arbitrary plane passing through a central axis of the nozzle.

Abstract: A method of producing molten steel supplies gaseous oxygen from a top blowing lance into a converter to perform decarburization refining of molten iron while adding a CaO-containing powdery dephosphorizing agent to simultaneously decarburize and dephosphorize the molten iron and includes supplying the dephosphorizing agent to a bath surface of the molten iron together with at least one gas jet from the top blowing lance and a dynamic pressure determined when a gas jet blown from respective lance nozzles of the top blowing lance impinges onto the bath surface of the molten iron is controlled to not more than 0.50 kgf/cm2.

Abstract: The invention relates to an injector apparatus (1) for the pyrometallurgical treatment of metals, molten metals and/or slags in a metallurgical unit or melting vessel, said apparatus comprising an injector device (2, 3) for producing a high-velocity gas jet (5) from an oxygen gas jet (6) and an ignited combustible gas/air mixture jet (7), in which the injector device (2, 3) comprises a de Laval nozzle element (8) for producing the oxygen gas jet (6), said de Laval nozzle element being arranged in a nozzle head part (41), and in which the combustible gas/air mixture (7) can be mixed by means of a mixing element (9) for mixing combustible gas (32) and air (36), wherein the de Laval nozzle element (8) and the mixing element (9) are arranged jointly along the center longitudinal axis (13) of the injector device (2, 3), one behind the other, such that they can be detached from one another.

Abstract: A method of making steel in a vessel comprising providing a lance for blowing oxygen on the surface of the steel in the vessel, the lance joined to a lance carriage and in communication with an accelerometer, the accelerometer in signal communication with a data acquisition module and a computer; charging the vessel with materials for steel making; lowering the lance into the vessel and injecting oxygen into the materials; acquiring a signal from the accelerometer indicative of lance vibration; processing the vibration signal to determine component frequencies of lance vibration; comparing the levels of the component frequencies to desired operating values; and adjusting at least one steel making process parameter based on the level of at least one of the component frequencies. The steel making process parameter to be adjusted may be oxygen flow rate through the lance.

Abstract: A method of making steel in a vessel comprising providing a lance for blowing oxygen on the surface of the steel in the vessel, the lance joined to a lance carriage and in communication with an accelerometer, the accelerometer in signal communication with a data acquisition module and a computer; charging the vessel with materials for steel making; lowering the lance into the vessel and injecting oxygen into the materials; acquiring a signal from the accelerometer indicative of lance vibration; processing the vibration signal to determine component frequencies of lance vibration; comparing the levels of the component frequencies to desired operating values; and adjusting at least one steel making process parameter based on the level of at least one of the component frequencies. The steel making process parameter to be adjusted may be oxygen flow rate through the lance.

Abstract: A multifunction injector (10, 11, 12) comprising a De Laval nozzle (20) adapted to act as a burner at subsonic or supersonic speed, combined with a plurality of nozzles (31, 32) for fuel and comburant respectively, arranged in two rings, concentric and co-axial to said De Laval nozzle (20) and externally protected by a specifically shaped protection cavity (40).

Abstract: Apparatus and process for producing metal products, in which a metal-containing charge material is melted in a melting unit, and a working gas, in particular an at least partially reducing working gas, is additionally produced in the melting unit. The working gas produced is extracted and if appropriate after cleaning, is used as a carrier gas, at least in part for—preferably pneumatic—transport of an at least partially reduced metal-containing material in the form of fine particles.

Abstract: A multifunction injector (10, 11, 12) comprising a De Laval nozzle (20) adapted to act as a burner at subsonic or supersonic speed, combined with a plurality of nozzles (31, 32) for fuel and comburant respectively, arranged in two rings, concentric and co-axial to said De Laval nozzle (20) and externally protected by a specifically shaped protection cavity (40).

Abstract: A method for blowing oxygen in a converter uses a top-blown lance having a Laval nozzle installed on its tip. The Laval nozzle has a back pressure of the nozzle Po(kPa) satisfying a formula, Po=FhS/(0.00465·Dt2), with respect to a oxygen-flow-rate FhS(Nm3/hr) per hole of the Laval nozzle determined from the oxygen-flow-rate FS(Nm3/hr) in a high carbon region in a peak of decarburization and a throat diameter Dt(mm). An exit diameter De of the Laval nozzle satisfies the following formula with respect to the back pressure of the nozzle Po(kPa), an ambient pressure Pe(kPa), and the throat diameter Dt(mm): De2≦0.23×Dt2/{(Pe/Po)5/7×[1−(Pe/Po)2/7]1/2}.

Abstract: The electric arc furnace is equipped with a supersonic injector comprising a so-called Laval nozzle arranged at a certain distance above the bath. The dimensions of the nozzle are calculated as a function of the desired flow rate of oxygen and the desired velocity of the jet, and the pressure of the oxygen at the intake of the nozzle is such that the static pressure of the jet at the exit of the injector is substantially equal to the pressure of the surrounding atmosphere. Preferably, the injector comprises an annular channel for injection of natural gas, and can be used in burner mode at the start of the melting of scrap iron. The velocity of the oxygen is then subsonic.

Abstract: A method for blowing oxygen in a converter uses a top-blown lance having a Laval nozzle installed on its tip. The Laval nozzle has a back pressure of the nozzle Po(kPa) satisfying a formula, Po=FhS/(0.00465·Dt2), with respect to a oxygen-flow-rate FhS(Nm3/hr) per hole of the Laval nozzle determined from the oxygen-flow-rate FS(Nm3/hr) in a high carbon region in a peak of decarburization and a throat diameter Dt(mm). An exit diameter De of the Laval nozzle satisfies the following formula with respect to the back pressure of the nozzle Po(kPa), an ambient pressure Pe(kPa), and the throat diameter Dt(mm).

Abstract: A metal refining method particularly useful with a basic oxygen steelmaking process, wherein during an initial period, refining oxygen is provided into the furnace headspace surrounded by a shroud comprising oxygen and inert gas, and during a subsequent period refining oxygen is provided into the furnace headspace surrounded by a flame shroud.

Abstract: An energy efficient, coal-based method and apparatus that are environmentally friendly which produce under pressure metallized/carbon product and molten metal directly from abundant coal or other carbonaceous material, and low cost fines (or ore concentrate) wherein the metal is devoid of gangue material and possesses the inherent advantage of retaining the heat for subsequent processing. This method and apparatus which are modular and highly integrated significantly reduce capital and operating costs; they also provide the capability selective placement of the reductant for the delivery of high levels of thermal energy input which leads to ease of desulflurization and high productivity. The technology herein disclosed is entirely closed and is applicable to various ores including ferrous and non-ferrous.

Abstract: This invention relates to making steel directly from ore concentrate and non-coking coal to which flux material is added. The method eliminates numerous steps by reducing the ore with the coal in a sealed chamber and under pressure termed “carbotreating” to make a fluxed iron/carbon product which after crushing, is injected while hot into a melting furnace. The hot product is melted with oxygen under reducing conditions using excess carbon from the coal to make a carburized molten iron and a slag low in FeO termed “oxymelting”. After the tapping of the slag, the carburized molten iron to which flux material is added, is blown with oxygen to make steel, CO, and a slag high in FeO termed “decarburizing”. The steel is tapped while the slag is retained in the furnace. All of the above steps are carried out in an efficient and environmentally sound manner which render the art of steelmaking significantly more economical than conventionally practiced.

Abstract: A refining method for decarburization by blowing by using a top-blown lance having a gas-supplying pipe of at least one independent line, wherein the absolute secondary pressure P.sub.0 of nozzle of the lance of at least one line is maintained to be not smaller than 0.7 times but not larger than 2.5 times of the properly expanding absolute secondary pressure P.sub.0p of nozzle of the lance, and the oxygen supplying rate is so changed that a maximum value of the absolute secondary pressure of the nozzle is not smaller than 1.1 times of a minimum value thereof. The top-blown lance used here has not less than 2 but not more than 10 shielding portions arranged in the openings at the end of the lance in a concentric polygonal shape or a concentric circular shape in cross section, has a ratio B/h of the length h (mm) of the short side to the length B (mm) of the long side of the openings separated by the shielding portions of from 10 to 225, has slit-like nozzles of which the ratio (B.multidot.h)/R is from 0.

Abstract: A method of improving post-combustion heat recovery in a vessel containing a charge of molten ferrous metal and slag includes the use of a lance for the introduction of oxygen gas into the charge. The method includes blowing oxygen into the charge through at least one first nozzle of the lance for refining the molten metal into steel. Oxygen is blown through at least one second nozzle of the lance from at least one location spaced above the first nozzle at an oxygen flow rate effective to produce foamy slag in an amount for obtaining a post-combustion heat transfer efficiency of at least about 40% without appreciable overflow of the slag from the vessel. The oxygen flow rate from the second nozzle is at a minimum at about a starting point of a peak decarburization period of the charge. Iron oxide containing pellets may also be added to the charge.

Abstract: Method and top blowing lance for decarburization refining chromium molten ferrous metal in which dust formation and chromium loss due to oxidation are suppressed and high productivity is achieved. Decarburization of molten ferrous metal is achieved by blowing gaseous oxygen into the molten metal in a refining furnace provided with a top blowing lance having a plurality of gas blowing nozzles at the tip of the lance. The gas blowing nozzles include at least one sub-nozzle provided at or near the lance axis and a plurality of main nozzles at an outer section of the lance. Blowing refining is carried out with oxygen flow from a plurality of the main nozzles at a flow rate higher than that from the sub-nozzle(s), when the carbon content in the molten metal is about 1 wt % or more.

Abstract: A method of improving the post-combustion heat recovery in a basic oxygen furnace by controllably forming a foamy slag. The foamy slag is generated by increasing the lance height and reducing the rate of lance height reduction during the oxygen blowing cycle. The foamy slag is controlled to prevent slopping by calculating the approximate starting point of the peak decarburization period for the charge and then adjusting the oxygen flow rate to be at a minimum at the commencement of the peak decarburization period.

Abstract: A lance intended for injecting oxygen and/or an inert gas into liquid steel comprises a metal supply tube which opens into a distributor from which issue a plurality of injection tubes arranged parallel and concentrically with respect to the longitudinal axis of the lance, these injection tubes being embedded in a sheath of refractory material. Preferably, the distributor comprises two chambers which are separate from each other, the first chamber communicating with the supply tube for a first gas and with a plurality of first injection tubes, and the second chamber communicating with a second supply pipe for another gas and with a plurality of second injection tubes.

Abstract: Process and apparatus for post combustion of reaction gases generated in a molten iron bath above the bath by means of at least one jet of oxidizing gases, whereby energy thereby produced is transferred to the bath and whereby the or each jet of oxidizing gases is injected with a swirl through one or more tuyeres towards the surface of the bath or the or each jet of oxidizing gases is injected in the form of a hollow jet through one or more tuyeres towards the surface of the bath.