US3212880A - Method of carrying out metallurgical processes - Google Patents

Method of carrying out metallurgical processes Download PDF

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Publication number
US3212880A
US3212880A US7733660A US3212880A US 3212880 A US3212880 A US 3212880A US 7733660 A US7733660 A US 7733660A US 3212880 A US3212880 A US 3212880A
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Prior art keywords
blowing
charge
downcomer
steel
oxygen
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English (en)
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Rinesch Rudolf
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Bot Brassert Oxygen Techik A G
BOT BRASSERT OXYGEN TECHIK AG
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Bot Brassert Oxygen Techik A G
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing
    • C21C5/32—Blowing from above
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/04—Manufacture of hearth-furnace steel, e.g. Siemens-Martin steel
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/4606—Lances or injectors
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/42—Constructional features of converters
    • C21C5/46—Details or accessories
    • C21C5/4606—Lances or injectors
    • C21C5/462—Means for handling, e.g. adjusting, changing, coupling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/87917—Flow path with serial valves and/or closures

Definitions

  • the materials contain combustible impurities, such as coal or iron particles, these impurities are ignited in contact with the oxygen and often cause a destruction of the hose lines.
  • nickelchronium steels have been used for the supply conduits.
  • the equipment becomes complicated and expensive; it is no longer possible to move the blowing tube or lance into and out of the reaction vessel with the ease required for the performance or refining processes.
  • the equipment is subjected to considerable mechanical wear. Aggregates having a particularly uniform structure must be used to reduce this wear. Virtually only those substances which have a uniform spherical particle structure are suitable. These substances must be prepared in a special preliminary process or particularly finely divided admixtures must be used. Lime in this form, however, has the disadvantage of a great hydration.
  • the field of application of processes and equipment using an oxygen-containing blast e.g. oxygen or oxygen enriched gas
  • the invention has as its object to provide a greater latitude in the use of the starting materials to be processed, particularly regarding the chemical heat content of the crude iron.
  • the method resides in that, at least during part of the blowing period, particulate solid, liquid and/ or gaseous material which is to be added to the charge or bath, is added to, and passes downwardly through, the interior of the blowing gas flowing through the tube or lance and the interior of the gas jet discharging from the tube or lance. It is believed that such ma- Another object of the invention is to expand "ice terials impinge on the surface of the charge or bath inside of the boundary of the reaction zone created by blowing of the gas jet on the surface of the charge or bath.
  • the material is introduced through use of a tube or downcomer extending centrally downwardly of the lance within the conduit or passage provided for flow of the blowing gas.
  • passage through the downcomer is effected under no pressure, i.e. gravity flow.
  • liquid or gaseous material is to be added it is effected under pressure.
  • the method according to the invention avoids the disadvantages of the known equipment, in which finely divided material is introduced into the reaction vessel in suspension in the carrier gas. According to the invention there is no danger of combustion of inflammable mate rials and there is no mechanical wear from abrasion or other effects.
  • inflammable or combustible materials such as coal, coke, oil, high calorific value gases, iron, silicon, maganese, aluminium or alloys of these substances can be introduced singly, in combination or in a mixture with slag-forming materials into the interior of the reaction zone if the chemical heat content of the charge to be blown is not sufficient for attaining or maintaining the desired reaction temperature.
  • inflammable or combustible materials such as coal, coke, oil, high calorific value gases, iron, silicon, maganese, aluminium or alloys of these substances can be introduced singly, in combination or in a mixture with slag-forming materials into the interior of the reaction zone if the chemical heat content of the charge to be blown is not sufficient for attaining or maintaining the desired reaction temperature.
  • crude iron having a low carbon content is to be converted into steel and scrap is to be melted at the same time
  • the heat of combustion of the impurities contained in the crude iron is not suflicient for attaining the refining temperature necessary for the
  • the problem may also reside in melting a solid charge consisting of crude iron and scrap and in subsequently converting it into steel.
  • the necessary heat may also be supplied by an addition of coal and other combustible materials.
  • coal, iron ore and slag-forming substances are simultaneously introduced into the reaction vessel by means of a downcomer or the like into the interior of the reaction zone to form under a reducing atmosphere a liquid charge similar in composition to crude iron, and this charge is then converted into steel under an oxidizing atmosphere.
  • the formation of a liquid charge may be begun when the vessel is empty. It is also possible to charge a portion of liquid crude iron at the beginning, and to increase this charge by the addition of coal and ore.
  • the supply rate should be so controlled that a liquid molten bath having the necessary temperature is obtained.
  • the conversion into steel is then carried out in the same vessel.
  • slag-forming substances such as CaO
  • the method according to the invention enables the very early formation of a reactive slag.
  • the finely divided slag-forming substances supplied in the interior of the jet are melted and react quickly with the impurities in the iron.
  • the method may be controlled in such a manner that the phosphorus content is reduced from 2.0% to 0.3-0.4% within a few minutes whereas the carbon content is still 2.0 to 2.5%. This has not been possible with any other process.
  • a person skilled in the art will understand that the latitude thus achieved in such a wide range enables a universal application of the method. Crude irons of any desired composition, solid crude iron and even ores and scrap may be processed with or without an addition of liquid charging materials.
  • the liquid charge may be composed of a part of the finished steel and of the final slag of a preceding charge and may be increased by an addition of ore and coal with simultaneous blowing.
  • a refining phase e.g., when the carbon content is 2.5 to 2.0% and a high phosphorus content is still present, a sudden oversupply of iron oxide, e.g., in the form of scarfing scale, may be added, followed by deslagging. This measure has the result of a very rapid removal of phosphorus.
  • the method according to the invention may also be used for refining and after-treating steel.
  • the possibility of a mutual regulation of the kind and amount of the added materials relative to the blowing agent, particularly a suitable adjustment of the oxygen supplied in dependence on the amount of coal or other carbonaceous material supplied enables the selective adjustment of an oxidizing, neutral or reducing atmosphere in the reaction vessel. For this reason it is possible, if desired, to provide for a reducing after-treating phase after the production of steel, and alloying elements, such as Mn, Cr, Ni may be added to the finished steel. In some cases it is necessary to heat the charge before adding alloying elements. This problem can also be easily solved with the aid of the method according to the invention.
  • a particularly advantageous and economical method of alloying is enabled by the method according to the invention in that the alloying substances are added in the form of oxides, such as chromium oxide, molybdenum oxide, manganese oxide and the like or in the form of ores containing such oxides, which ores are supplied in a mixture with reducing substances. Powdered coal or powdered aluminium are used as reducing substances and a reducing atmosphere is adjusted. Owing to the high temperature in the reduction zone it is possible in this way to reduce the oxides and to alloy the iron. This has not been possible before with any other blowing process and it was necessary to use the much more expensive pure metals or master alloys With iron as alloying admixtures.
  • oxides such as chromium oxide, molybdenum oxide, manganese oxide and the like
  • ores containing such oxides which ores are supplied in a mixture with reducing substances.
  • Powdered coal or powdered aluminium are used as reducing substances and a reducing atmosphere is adjusted. Owing to the high
  • a particularly advantageous application of the invention involves the simultaneous and continuous supply of oxygen and ores in hearth furnaces in the production of steel, using powdered or granular ores and, in addition, slag-forming substances, such as lime, if desired, as solid materials.
  • the ores may consist of powdered or granular iron ore or of other ores.
  • the ores used may preferably consist of ores or ore concentrates of metals which are to remain as alloying elements in the steel. Suitable ores of this kind include particularly chromium ores, molybdenum ores and manganese ores.
  • the open-hearth furnaces can be loaded to their full heat capacity.
  • the yield is increased and the output of existing plants is increased.
  • the most important advantage resides in that the refining process is greatly accelerated without disturbing secondary effects.
  • FIG. 1 is a diagrammatic representation of a plant
  • FIG. 2 an enlarged vertical sectional view of the mouth portion of the lance or blowing tube
  • FIG. 3 a vertical sectional view of the upper part of the blowing device.
  • FIG. 4 is a perspective view showing in section the jet produced with the device.
  • FIG. 5 is a diagrammatical longitudinal sectional view of a plant.
  • FIG. 1 shows a blowing tube 2 arranged to be lifted out of and lowered into a reaction vessel 1, which in this case is a converter having a refractory lining.
  • a support 3 having a rack 4 or another guide element is provided to provide for a vertical guidance of the blowing tube.
  • the blowing tube (FIG. 2) consists of an inner tube 5, in which the blowing fluid, such as oxygen, is supplied under pressure, and an external cooling shell 6.
  • a guide tube 7 is arranged in the space between the inner tube 5 and the shell 6 to provide for a circulation of the cooling agent.
  • the inner and outer tubes are integrally connected and form the nozzle 9, which in the illustrative embodiment has the form of a Laval nozzle g iying rise to an expansion zone.
  • the inner tube 5 is constricted to form a throttle 10.
  • a downcomer 11 is centrally disposed in the blowing tube. The lower end of the downcomer is adjacent to the throttle. The upper portion of the downcomer extends through the wall 13 of the oxygen supply conduit 5, which is curved at the top.
  • a stuffing box 14 and a gasket 16 which can be tightened by screws 15 the upper part 12 of the downcomer is sealed against the insertion opening 17, which carries a flange 18 (FIG. 3).
  • a flange 19 is welded to the downcomer and is connected to the flange 18 by screws 20. By an adjustment of the screws 20 the downcomer can be axially displaced relative to the blowing tube in the direction thereof.
  • the downcomer At the upper end the downcomer is connected to a hopper 21, which, in this case, widens like a funnel and serves for charging solid materials.
  • the hopper 21 communicates with the outer atmosphere.
  • 22 is a valve consisting, e.g., of a slide valve. As has been mentioned above and indicated with dash lines in FIGURES 1 and 2, the downcomer with the hopper 21 is axially displaceable relative to the inner tube 5.
  • FIG. 4 shows what is believed to be the lower part of hollow-conical jets thus produced.
  • 23 is a jet of relatively small diameter, which results in the formation of the reaction ring 24.
  • 25 is a jet larger in diameter to form the reaction ring 26 correspondingly larger in diameter.
  • the materials are introduced into the interior 27 of the reaction ring.
  • the funnel-shaped hopper 21 at the upper end of the downcomer is disposed adjacent to a charging device which consists of a supply vessel 28 and a belt conveyor 29.
  • the belt conveyor may be provided with a weighing device and may be pivotally mounted to enable the feeding operation to follow the vertical lifting and lowering movement of the downcomer and blowing tube.
  • a feed tube with conveyor screw may be used; this feed tube is preferably filled with inert gas.
  • the dimensions of the blowing device and, in accord ance therewith, the size of the reaction zone may be adjusted to the size of the charge to be blown.
  • a blowing tube having an inner tube 30 mm. in diameter at the throttle 10.
  • the axially inserted downcomer has in this case an outside diameter of about 25 mm. and an inside diameter of about 20 mm.
  • FIG. 5 shows an open hearth furnace wherein 30 is the roof, 31 the bath and 32 are the doghouses of the furnaces.
  • the blowing device 33 consists of a blowing tube 34 surrounded by a cooling shell and a downcomer 35 centrally disposed in the blowing tube extends vertically through the roof 30.
  • the central downcomer serves for feeding solid materials and, as has been described more in detail hereinbefore, can be lifted and lowered relative to the blowing tube.
  • the upper end 36 of the downcomer where the latter communicates with the outside atmosphere, is suitably flared like a funnel.
  • 37, 33 and 39 respectively, designate the oxygen supply conduit and the conduits for the supply and discharge of the coolant.
  • blowing device 33 passes through the furnace roof 30 it is surrounded by a cooling cylinder 40 having a water inlet and outlet 41 and 42, respectively, and is guided in this cooling cylinder so that the device can be vertically lifted and lowered.
  • Conveyor belts 43 and 44 are disposed above the blowing device and are fed with ore and slag-forming materials from supply containers 45 and 46.
  • a reaction field 47 is believed produced on the bath surface; the ore and, if desired, other materials are introduced under no pressure into the interior of this field.
  • the process can be controlled as desired without overheating and other disturbing secondary elfects.
  • Example 1 Conversion of steel-making crude iron into steel 50 kg. of scarfing scale and 30 kg. bauxite were added to a crucible charge of 400 kg. scrap and 6,540 kg. liquid crude iron having a composition of 4.12% C, 0.85% Si, 1.65% Mn, 0.196% P, 0.060% S. Then a blowing device as explained more fully in FIGS. 1 to 3 of the drawings was moved into the crucible.
  • the inner tube had a diameter of 30 mm. at the throttle and the downcomer had an inside diameter of 20mm. and extended about 15 mm. below the throttle into the conically widening mouth portion of the nozzle.
  • the nozzle orifice was adjusted to a distance of 400 mm.
  • the bath was deslagged. The temperature was 1605 C. The steel was tapped. The recovery was 89%.
  • a blowing device as has been described in detail in the drawings and in the foregoing example was moved into the crucible. The distance of the nozzle orifice from the bath surface was 600 mm. Oxygen blowing began at a pressure of 10 kg./sq. cm. superatmospheric pressure. A reaction zone was formed. During a blowing period of 13 minutes, 450 kg.
  • the steel had the following composition: 1.14% C, 0.02% Si, 0.07% Mn, 0.187% P, 0.043% S.
  • the slag had the following composition: 15.23% FeO, 0.74% MnO, 9.84% SiO 39.40% 0.210, 4.46% MgO, 18.21% P 0 8.25% A1 0
  • the temperature was 1520 C.
  • the bath was deslagged, the crucible brought into blowing position and additional slag-forming substances, consisting of kg. scarfing scale, 50 kg. bauxite and 400 kg. lime in lumps added through a chute. Then the blowing tube was inserted into the crucible and the blowing continued for 6.5 minutes under an oxygen pressure of 14 kg./ sq. cm. and with nozzle orifice at a distance of 400 mm. from the bath. During this last blowing period the downcomer was maintained closed by a valve. After the blowing was terminated a steel sample was taken and had the following values: 0.02% C, 0% Si, 0.03% Mn, 0.015% P, 0.021% S. The temperature was 1610 C.
  • a charge of 4,910 kg. crude iron having a composition of 4.10% C, 0.75% Si, 1.60%.Mn, 0.170% P and 0.050% S was blown and converted into steel.
  • the tapping temperature was to be 1640 to 1650 C.
  • 12% scrap equal to 590 kg. scrap, could be melted together with the crude iron. It was desired, however, to process 1700 kg. scrap, which is 25.7%.
  • the problem to be solved resided in the additional melting of 1110 kg. scrap.
  • the charge was to be heated by an addition of coke breeze.
  • the coke breeze available had the following analysis: 17.10% H O, 10.99% ash, 0.91% S (dry), 72.12% C (dry) and 1.76% volatile constituents.
  • Its gross calorific value was 5868 kg.-cal., the net calorific value was 5754 kg.-cal.
  • Its grain size was to 3 mm.
  • a charge consisting of 4,910 kg. crude iron and 1,700 kg. scrap was introduced into the crucible provided with a refractory lining. 500 kg. lump lime, 50 kg. scarfing scale, 30 kg. bauxite and 20 kg. fluorspar were added as slag-forming admixtures.
  • a blowing device of the type described herein was set to a distance of 600 mm. from the bath surface; oxygen was supplied under a pressure of to 11 kg./sq. cm. superatmospheric pressure. From the 3rd to the 12th blow minute, 212 kg. coke breeze of the composition described hereinbefore were introduced under no pressure into the interior of the jet by means of the downcomer. Deslagging was eifected after a total blow time of 21 minutes. The final analysis of the resulting steel was: 0.05% C, 0.18% Mn, 0.011% P. The temperature was 1650 C.
  • the efiiciency of the fuel added according to the invention is calculated as follows: In view of the values.
  • C steel 0.15 kg.-cal./kg.
  • the method of working was the same as in Examp1e 3.
  • the blowing began after the charge had been introduced and 500 kg. lump lime, 50 kg. scarfing scale and 30 kg. fluorspar added.
  • the distance of the blowing tube from the bath surface was 700 mm.
  • 240 kg. powdered coal were added from the 3rd to the 13th blow minutes. Deslagging was effected at the end of the refining process.
  • the steel had a composition of 0.06% C, 0.38% Mn, 0.010% P.
  • the temperature was 1705 C.
  • the degree of utilization of the powdered coal' was 72%.
  • Example 5 Heating of a charge during the main boiling period by means of lignite breeze Using a charge of 5320 kg. crude iron having a similar composition as in Example 3, 1400 kg. scrap (20.2%) were melted. To heat the charge, lignite breeze having the following composition: 17.41% water, 22.72% ash, 1.63% S (dry), 56.86% C (dry) and 8.33% volatiles was used. The gross calorific value was 5048 kg.-cal., the net calorific value was 4863 kg.-cal.
  • the method of working was the same as in Examples 3 and 4.
  • the blowing began after the charge had been introduced and 550 kg. lump lime, 50 kg. scarfing scale, 30 kg. bauxite and 30 kg. fluorspar added.
  • the distance of the blowing tube from the bath surface was 700 mm.
  • 350 kg. lignite breeze were added from the 3rd to the 14th minute of the blow.
  • Deslagging was effected at the end of the refining process.
  • the steel had a composition of 0.07% C, 0.37% Mn, 0.009% P.
  • the temperature was 1645 C.
  • the degree of utilization of the lignite breeze was 60% Example 6.Heating of a melt under reducing conditions A charge was formed from 300 kg. scrap and 6400 kg.
  • liquid crude iron having a composition of 4.08% C, 0.89% Si, 1.47% Mn, 0.142% P, 0.057% S.
  • a blowing device of the type disclosed herein but with a closed downcomer (pressure 14 kg./sq. cm. superatmospheric pressure, nozzle distance 400 mm)
  • a blowing period of 16.5 minutes, during which kg. broken limestone were added in portions through a chute, the supply of oxygen was interrupted, the blowing tube withdrawn and samples taken.
  • the composition of the steel was: 0.03% C, 0% Si, 0.27% Mn, 0.022% P, 0.030% S.
  • the temperature was 1610 C.
  • the temperature was increased. After the bath had been completely deslagged the crucible was again moved to its blowing position and the blowing device inserted into the crucible. The distance from the bath of the blow ing device was adjusted to 400 mm., the oxygen pressure was adjusted to 6 kg./sq. cm. superatmospheric pressure and the blowing of the bath continued for 5 minutes. At the same time, 80 kg. powdered coke and 12 kg. lime dust were introduced through the downcomer under no pressure into the interior of the reaction zone. After this heating period the oxygen supply was interrupted and another sample was taken. The composition of the steel was as follows: 0.09% C, 0% Si, 0.27% Mn, 0.025% P, 0.025% S. The temperature was 1640 C. The steel was tapped and teemed. The recovery was 88.5%.
  • Example 7 Heating of a melt under neutral conditions A charge was formed from 350 kg. scrap and 6330 kg. liquid crude iron, having a composition of 4.01% C, 0.90% Si, 1.40% Mn, 0.17% P, 0.050% S and 50 kg. scale, 30 kg. bauxite and 450 kg. lime in lumps were added. Then the charge was blown with oxygen using a blowing device of the kind disclosed herein but with the downcomer closed (pressure 14 kg./sq. cm., nozzle distance 400 mm.). After a blowing period of 16 minutes, during which kg. broken limestone were supplied in portions through a chute, the oxygen supply was interrupted, the blowing tube removed and samples taken. The composition of the steel was: 0.05% C, 0% Si, 0.27% Mn, 0.018% P, 0.025% S. The temperature was 1580 C.
  • Example 8 Heating of a melt under oxidizing conditions A charge was formed from 400 kg. scrap and 6450 kg. liquid crude iron having a composition of 4.10% C, 0.95% Si, 1.50% Mn, 0.164% P, 0.055% S and 50kg. scale, 30 kg. bauxite and 450 kg. lime in lumps were added. Then the charge was blown with a blowing device as in the previous examples but with downcomer closed (pressure 14 kg./ sq. cm. superatmospheric pressure, nozzle distance 400 mrn.). After a blowing period of 16 minutes, in which 90 kg. broken limestone were added in portions through a chute, the oxygen supply was interrupted, the blowing tube removed and samples taken. The composition of the steel was: 0.04% C, 0% Si, 0.30% Mn, 0.027% P, 0.023% S. The temperature was 1590 C.
  • Example 9 Alloying a melt with simultaneous neutral heating A charge was formed from 300 kg. scrap and 6230 kg. liquid crude iron having a composition of 4.12% C, 0.97% Si, 1.42% Mn, 0.170% P and 0.044% S. After an addition of 50 kg. scale, 30 kg. bauxite and 450 kg. lime in lumps the charge was blown with the blowing device as in the previous examples but with the downcomer closed (pressure 14 kg./sq. cm. superatmospheric pressure, nozble distance 400 mrn.). After a blowing period of 15.5 minutes, between the sixth and twelfth minutes of which 80 kg. broken limestone were added in portions, the oxygen supply was interrupted, the blowing tube withdrawn and a sample taken. The composition of the steel was as follows: 0.03% C, 0% Si, 0.30% Mn, 0.018% P, 0.027% S. The temperature was 1605 C.
  • ferro-chromium having a composition of 1.39% C, 0.80% Si, 0.040% P, 0.076% S, 66.10% Cr were added through a chute. Then the oxygen supply was interrupted, the blowing device moved out of the crucible and samples taken.
  • the composition of the steel was: 0.05% C, 0% Si, 0.28% Mn, 0.018% P, 0.027% S, 0.97% Cr.
  • the temperature was 1640 C. After tapping the recovery was 86.2%.
  • Example 10 Increase of a charge by reduction of are A charge was formed from 4800 kg. liquid crude iron having a composition of 4.05% C, 0.97% Si, 1.53% Mn, 1.68% P and 0.030% S. After 50 kg. scale, 30 kg. bauxite and 150 kg. lime in lumps had been added the charge was blown with the blowing device as in the previous examples but with the downcomer closed (pressure 14 kg./sq. cm., nozzle distance 400 mrn.). After a blowing period of 6.5 minutes the oxygen supply was interrupted, the blowing tube removed and a sample taken. The composition of the steel was as follows: 2.10%. C, 0% Si, 0.58% Mn, 0.104% P, 0.028% S. The temperature was 1560 C.
  • the crucible was moved back into blowing position and the blowing device moved into the crucible.
  • the nozzle orifice was adjusted to a distance of 600 mm. from the bath, the oxygen pressure adjusted to 14 kg./ sq. cm. superatmospheric pressure and the blowing of the bath continued for 28.5 minutes.
  • 1,500 kg. fine ore, 1,000 kg. powdered coke and 210 kg. lime dust were simultaneously added under no pressure through the downcomer into the interior of the jet and thereby into the interior of the reaction zone.
  • the ore had the following composition: 71% Fe, 0.1% Mn, 1.7% 306 0.05% CaO, 0.01% S, 0.08% P, 4.5% A1 0 0.1%
  • the composition of the steel was as follows: 2.27% C, 0% Si, 0.25% Mn, 0.078% P, 0.035% S. The temperature was 1280 C.
  • Example ]1 Conversion of high-phosphorus crude iron into steel A charge was formed from 6450 kg. liquid crude iron having a composition of 3.80% C, 0.83% Si, 0.45% Mn, 0.950% P, 0.040% S. After an addition of 150 kg. scarfing scale and 50 kg. bauxite the charge was blown by a blowing device as in the previous examples so that a reaction zone was formed. The distance of the blowing device from the bath was 400 mm., the oxygen pressure was 10 kg./sq. cm. superatmospheric pressure. During the first blowing period of 9 minutes, 400 kg. lime dust were added under no pressure through the downcomer and sucked from the mouth of the downcomer into the interior of the jet and moved into the interior of the reaction zone.
  • the composition of the steel in this stage was: 2.10% C, 0.06% Si, 0.18% Mn, 0.092% P, 0.037% S.
  • the composition of the slag was: 18.00% FeO, 2.30% MnO, 10.75% SiO ,40.88% CaO, 4.43% MgO 12.78% P 0 7.31% A1 0
  • the temperature was 1520" C.
  • the distance of the blowing device from the bath was 400 mm. and the oxygen pressure was 10 kg../sq. cm. superatmospheric pressure.
  • the oxygen pressure was 10 kg../sq. cm. superatmospheric pressure.
  • 450 kg. lime dust were supplied under no pressure through the downcomer and sucked up from the mouth of the downcomer into the interior of the jet and brought into the interior of the reaction zone.
  • the oxygen supply was interrupted, the blowing device removed and 50 kg. ore in lumps added to the bath in one batch through a chute. A violent reaction ensued for 2 to 2.5 minutes.
  • the crucible was tilted and samples taken.
  • the compoSitiOn of the steel at this stage was: 1.98% C, 0% Si, 0.25% Mn, 0.225% P, 0.046% S.
  • the composition of the slag was: 16.30% FeO, 6.28% MnO, 3.64% SiO 42.30% CaO, 1.64% MgO, 21.90% P 0 5.23% A1 0
  • the temperature was 1540 C.
  • the crucible After deslagging, the crucible was moved back to its blowing position. 100 kg. scale, 50 kg. bauxite and 400 kg. lime in lumps were introduced by means of a chute and the blowing continued under a pressure of 14 kg./ sq. cm. superatmospheric pressure and with .a nozzle distance of 400 mm. while the downcomer was closed. The duration of this second blowing period was 6.5 minutes.
  • the blowing device was moved out of the crucible, the crucible tilted and a steel sample taken.
  • the composition was: 0.03% C, 0% Si, 0.10% Mn, 0.014% P, 0.020% S.
  • the temperature is 1655 C. After deslagging, the steel was tapped and teemed. The recovery was 85.7%.
  • a method of carrying out metallurgical processes comprising blowing an oxygen-containing gas against the surface of a charge comprising molten crude iron in a vessel having a refractory lining, said gas being blown through an annular orifice to form an annular jet impinging on said surface in an annular zone, said jet bounding and defining a passage within said jet, and discharging solid particles by gravity through said passage against the surface of said charge inwardly of said annular zone during at least part of the time said gas is being blown against said surface of said charge.
  • said gas is selected from the group consisting of oxygen and oxygenenriched gases.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Carbon Steel Or Casting Steel Manufacturing (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Vertical, Hearth, Or Arc Furnaces (AREA)
US7733660 1959-12-24 1960-12-21 Method of carrying out metallurgical processes Expired - Lifetime US3212880A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AT939359A AT218554B (de) 1959-12-24 1959-12-24 Verfahren und Vorrichtung zur Durchführung metallurgischer Prozesse, insbesondere zum Frischen oder Vorfrischen von Roheisen, zum Feinen und Legieren von Stahl
AT217160A AT226753B (de) 1959-12-24 1960-03-21 Verfahren zum Frischen von Roheisen

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AT (1) AT226753B (en(2012))
BE (1) BE598355A (en(2012))
DD (1) DD52149A (en(2012))
ES (2) ES263212A1 (en(2012))
GB (2) GB970858A (en(2012))
LU (1) LU39479A1 (en(2012))
OA (1) OA01858A (en(2012))

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3304173A (en) * 1961-07-27 1967-02-14 United States Steel Corp Method of adding solids and oxygen to an open hearth furnace
US3317309A (en) * 1962-11-30 1967-05-02 Voest Ag Method for melting artificial scrap
US3323905A (en) * 1963-09-23 1967-06-06 Oesterr Alpine Montan Method and apparatus for adding agents for forming and/or treating the slag in iron baths
US3502313A (en) * 1966-05-03 1970-03-24 Richard L Pastorius Steel producing plant with umbilically operative furnace top means
US5377960A (en) * 1993-03-01 1995-01-03 Berry Metal Company Oxygen/carbon blowing lance assembly
EP1431402A1 (en) * 2001-12-11 2004-06-23 CENTRO SVILUPPO MATERIALI S.p.A. Device apt to feed powdered substances onto a metal-slag bath surface and use thereof

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2446511A (en) * 1946-08-21 1948-08-03 Air Liquide Open-hearth steelmaking
US2515670A (en) * 1946-10-22 1950-07-18 Air Reduction Manufacture of open-hearth steel
US2593505A (en) * 1948-04-10 1952-04-22 Hydrocarbon Research Inc Metal refining process
US2598393A (en) * 1948-10-25 1952-05-27 Kalling Bo Michael Sture Method in carrying out treatment of melted pig iron or other alloyed iron
DE845643C (de) * 1949-09-21 1952-08-04 Oesterr Alpine Montan Vorrichtung und Verfahren zum Blasen von Gasen gegen die Oberflaeche von Metallschmelzen
DE898309C (de) * 1951-12-28 1953-11-30 Stahl Und Roehrenuntersuchunge Vorrichtung zum Behandeln von fluessigem Roheisen
US2817584A (en) * 1954-05-25 1957-12-24 August Thyssen Hutte Ag And Do Method for refining pig iron
US2836411A (en) * 1954-05-28 1958-05-27 Huettenwerk Oberhausen Ag Blowing nozzle for the refining of metals
US2862811A (en) * 1954-09-14 1958-12-02 Stora Kopparbergs Bergslags Ab Continuous iron and steel making in a rotary vessel
US2937864A (en) * 1957-09-13 1960-05-24 Steel Co Of Wales Ltd Gun assembly used in an open hearth furnace
FR1226680A (fr) * 1959-02-27 1960-07-15 Siderurgie Fse Inst Rech Procédé et dispositif pour améliorer le rendement thermique de l'affinage de la fonte par jet d'oxygène pur
US2950186A (en) * 1957-03-02 1960-08-23 Siderurgie Fse Inst Rech Method for top blowing pulverulent burnt lime and oxygen into cast iron for refining same
US2988443A (en) * 1958-04-30 1961-06-13 A R B E D Acieries Reunies De Method for producing steel
US2990271A (en) * 1960-04-08 1961-06-27 Arthur H Dierker Method of producing silvery pig iron
US3001864A (en) * 1952-12-09 1961-09-26 Air Reduction Method for introducing solid materials into molten metal

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2446511A (en) * 1946-08-21 1948-08-03 Air Liquide Open-hearth steelmaking
US2515670A (en) * 1946-10-22 1950-07-18 Air Reduction Manufacture of open-hearth steel
US2593505A (en) * 1948-04-10 1952-04-22 Hydrocarbon Research Inc Metal refining process
US2598393A (en) * 1948-10-25 1952-05-27 Kalling Bo Michael Sture Method in carrying out treatment of melted pig iron or other alloyed iron
DE845643C (de) * 1949-09-21 1952-08-04 Oesterr Alpine Montan Vorrichtung und Verfahren zum Blasen von Gasen gegen die Oberflaeche von Metallschmelzen
DE898309C (de) * 1951-12-28 1953-11-30 Stahl Und Roehrenuntersuchunge Vorrichtung zum Behandeln von fluessigem Roheisen
US3001864A (en) * 1952-12-09 1961-09-26 Air Reduction Method for introducing solid materials into molten metal
US2817584A (en) * 1954-05-25 1957-12-24 August Thyssen Hutte Ag And Do Method for refining pig iron
US2836411A (en) * 1954-05-28 1958-05-27 Huettenwerk Oberhausen Ag Blowing nozzle for the refining of metals
US2862811A (en) * 1954-09-14 1958-12-02 Stora Kopparbergs Bergslags Ab Continuous iron and steel making in a rotary vessel
US2950186A (en) * 1957-03-02 1960-08-23 Siderurgie Fse Inst Rech Method for top blowing pulverulent burnt lime and oxygen into cast iron for refining same
US2937864A (en) * 1957-09-13 1960-05-24 Steel Co Of Wales Ltd Gun assembly used in an open hearth furnace
US2988443A (en) * 1958-04-30 1961-06-13 A R B E D Acieries Reunies De Method for producing steel
FR1226680A (fr) * 1959-02-27 1960-07-15 Siderurgie Fse Inst Rech Procédé et dispositif pour améliorer le rendement thermique de l'affinage de la fonte par jet d'oxygène pur
US2990271A (en) * 1960-04-08 1961-06-27 Arthur H Dierker Method of producing silvery pig iron

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3304173A (en) * 1961-07-27 1967-02-14 United States Steel Corp Method of adding solids and oxygen to an open hearth furnace
US3317309A (en) * 1962-11-30 1967-05-02 Voest Ag Method for melting artificial scrap
US3323905A (en) * 1963-09-23 1967-06-06 Oesterr Alpine Montan Method and apparatus for adding agents for forming and/or treating the slag in iron baths
US3502313A (en) * 1966-05-03 1970-03-24 Richard L Pastorius Steel producing plant with umbilically operative furnace top means
US5377960A (en) * 1993-03-01 1995-01-03 Berry Metal Company Oxygen/carbon blowing lance assembly
EP1431402A1 (en) * 2001-12-11 2004-06-23 CENTRO SVILUPPO MATERIALI S.p.A. Device apt to feed powdered substances onto a metal-slag bath surface and use thereof

Also Published As

Publication number Publication date
ES263212A1 (es) 1961-06-16
DD52149A (en(2012)) 1900-01-01
AT226753B (de) 1963-04-10
GB970858A (en) 1964-09-23
LU39479A1 (en(2012)) 1961-01-30
BE598355A (fr) 1961-04-14
ES266188A1 (es) 1961-06-16
GB970859A (en) 1964-09-23
OA01858A (fr) 1970-01-14

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