US3486882A - Continuous steel making process - Google Patents
Continuous steel making process Download PDFInfo
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- US3486882A US3486882A US753336*A US3486882DA US3486882A US 3486882 A US3486882 A US 3486882A US 3486882D A US3486882D A US 3486882DA US 3486882 A US3486882 A US 3486882A
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- steel
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- refining vessel
- refining
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- 238000009628 steelmaking Methods 0.000 title description 3
- 239000000463 material Substances 0.000 description 73
- 238000007670 refining Methods 0.000 description 58
- 229910000831 Steel Inorganic materials 0.000 description 32
- 239000010959 steel Substances 0.000 description 32
- 238000000034 method Methods 0.000 description 31
- 230000000476 thermogenic effect Effects 0.000 description 28
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 26
- 229910052760 oxygen Inorganic materials 0.000 description 26
- 239000001301 oxygen Substances 0.000 description 26
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 23
- 239000007787 solid Substances 0.000 description 22
- 239000002893 slag Substances 0.000 description 19
- 239000007789 gas Substances 0.000 description 16
- 239000000203 mixture Substances 0.000 description 16
- 229910052751 metal Inorganic materials 0.000 description 15
- 239000002184 metal Substances 0.000 description 15
- 239000008188 pellet Substances 0.000 description 13
- 229910052742 iron Inorganic materials 0.000 description 11
- 238000002844 melting Methods 0.000 description 10
- 230000008018 melting Effects 0.000 description 10
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 8
- 239000006260 foam Substances 0.000 description 8
- 239000011343 solid material Substances 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 6
- 239000000571 coke Substances 0.000 description 5
- 229910000519 Ferrosilicon Inorganic materials 0.000 description 4
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- 230000009466 transformation Effects 0.000 description 4
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 239000012159 carrier gas Substances 0.000 description 3
- 238000002485 combustion reaction Methods 0.000 description 3
- -1 for instance Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 229910052698 phosphorus Inorganic materials 0.000 description 3
- 239000011574 phosphorus Substances 0.000 description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 2
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 235000011941 Tilia x europaea Nutrition 0.000 description 2
- 229910001882 dioxygen Inorganic materials 0.000 description 2
- 239000004571 lime Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000011449 brick Substances 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000012768 molten material Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000005453 pelletization Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 235000012239 silicon dioxide Nutrition 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
- 239000002912 waste gas Substances 0.000 description 1
Images
Classifications
-
- 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
- C21C5/56—Manufacture of steel by other methods
- C21C5/567—Manufacture of steel by other methods operating in a continuous way
-
- 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
-
- 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
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S75/00—Specialized metallurgical processes, compositions for use therein, consolidated metal powder compositions, and loose metal particulate mixtures
- Y10S75/957—Continuous refining of molten iron
Definitions
- the gaseous oxygen is introduced into the vessel from above in form of a jet so as to transform part of the mixture into a metal-slag foam which is continuously withdrawn by overow from the reuing vessel at such a rate that the amount of molten mass therein remains substantially constant.
- the present invention relates to a process of making steel and, more particularly, the present invention is concerned with a process of making steel which requires only one melting of the steel-forming raw material.
- the present invention is specifically concerned with making steel from prereduced, solid, steel-forming ⁇ material.
- the present invention relates to a method yof continuously producing steel comprising the steps of continuously introducing into a refining vessel, containing a mixture of molten steel-forming materials, a solid prereduced steel-forming ice material at an elevated temperature below the melting point of the prereduced material, simultaneously and continuously introducing thermogenic material and gaseous oxygen respectively in such amounts into the refining vessel and the molten ⁇ mass therein so that the amount of thermogenic material by exothermic reaction with the oxygen will insure melting of the simultaneously and continuously introduced steel forming material and that the amount of the simultaneously introduced oxygen is sufficient to convert the continuously introduced prereduced steel-forming material into steel to thus obtain in the vessel a mixture of molten steel and slag.
- the gaseous oxygen is introduced in a jet from above into the mixture in the refining vessel to transform at least part of the mixture in the refining vessel into a metal-slag foam, and continuously withdrawing by overflow the metalslag foam from the refining vessel at such a rate that the amount of molten mass in the refining vessel remains substantially constant.
- prereduced solid material is intended to denote iron ores which have been submitted to a reducing treatment such that between about 40 and 100% of the bound oxygen of the iron ore will have been removed by means of reducing agents such as, for instance, carbon. If for the purpose of producing the prereduced solid material an excess amount of carbon or the like is applied, such excess amount may be retained in the prereduced solid material which is introduced into the refining vessel.
- reducing agents such as, for instance, carbon.
- thermogenic materials is to be understood, in the context of the present specification and claims, as denoting materials which react in an exothermic manner with oxygen or oxidizing substances.
- the amount of thermogenic material which is to be simultaneously introduced with the prereduced solid material, in accordance with the present invention, must be such that the heat requirements of the process are supplied by the heat ⁇ provided by the enthalpy of the prereduced material, which depends on the temperature at which the prereduced material is introduced into the refining vessel (which temperature preferably will be an elevated temperature below the melting point of the prereduced material), the enthalpy of the thermogenic material and the heat formed by oxidation of the same, and the combustion heat of gases which are oxidized during the refining process, primarily the combustion of CO into CO2.
- thermogenic material Elements which form part of the thermogenic material and which may be oxidized in an exothermic reaction include, for instance, carbon, silicon and phosphorus.
- the heat which is thus made available must be sufiicient to balance the thermic losses which correspond to the enthalpy of the slag, the enthalpy of the Withdrawn molten steel, the enthalpy of the gases, and other thermic losses due to radiation, etc.
- the above described process may comprise one or more of the following features:
- Prereduced steel-forming material may be introduced in the form of pellets, generally having a size of between 2 and 40 mm. and preferably between l0 and 20 mm.
- the solid prereduced steel-forming material may be introduced in pulverulent form, for instance having a particle size of between microns and 2 mm. and preferably having a particle size between 100 microns and l
- the prereduced solid steel-forming material may be sponge iron and, preferably, the particle size of the sponge iron may be greatly reduced and a pulverulent mass of sponge iron introduced into the refining vessel.
- a strongly thermogenic material such as, for instance, coke may be additionally, simultaneously with the prereduced material, and continuously introduced into the refining vessel.
- the solid prereduced steel-forming material and the thermogenic material may be jointly introduced into the refining vessel in the form of a mixture of these two types of materials.
- thermogenic material may be introduced pneumatically in pulverulent form, for instance in the form of a pulverulent suspension of thermogenic material in a suitable carrier gas.
- At least ⁇ a portion of the gas produced during the refining process within the molten metal mass in the relining vessel may be oxidized and burned by reaction with a portion of the oxygen introduced into the molten metal, before the gas reaches the upper level of the mass of molten metal in the refining vessel.
- thermogenic materials are additionally introduced into the refining vessel.
- predeuced, solid steel-forming material into the refining vessel, and into the molten steel bath contained therein, in the form of pellets which, due to their geometrical shape, are particularly suitable for being introduced in a regular and controllable fiow so that within given time periods the same amounts of prereduced, solid steel HY forming material are introduced into the refining vessel.
- the prereduced, solid, steel-forming material is introduced in pulverulent form, by being blown into the refining vessel suspended in a hot reducing gas.
- a hot reducing gas serving as carrier for the pulverulent, prereduced, steel-forming material may also be derived from the waste gas leaving the refining vessel.
- the present invention also contemplates, as discussed further above, the simultaneous introduction of solid, strongly thermogenic materials, which, for instance may be carbon in the form of coke or graphite, phosphorus in the form of ferrophosphorus, silicon in the form of ferrosilicon and aluminum in the form of ferroaluminum.
- solid, strongly thermogenic materials which, for instance may be carbon in the form of coke or graphite, phosphorus in the form of ferrophosphorus, silicon in the form of ferrosilicon and aluminum in the form of ferroaluminum.
- FIG. l is a schematic view showing an 'arrangement for carrying out the method of the present invention.
- FIG. 2 is a view of an embodiment thereof.
- reference numeral 1 indicates a heat insulated hopper made of refractory bricks and containing a relatively small amount of prereduced, hot, solid, steel-forming pellets which are introduced into hopper 1 in a continuous manner from a conventional pelletizing device (not shown).
- the pellets may be produced in any conventional manner and producing of the pellets does not form part of the present invention.
- the mass of pellets is then continuously and evenly introduced through a refractory conduit 3 into a continuous refining vessel 2 containing molten steel in its lower portion.
- the rate of introduction of pellets into a refining vessel 2 is controlled by means of a conventional, revolving distributor wheel 4.
- a stream of oxygen under pressure having pulverulent lime suspended therein is introduced into refining vessel 2 from above in form of a jet through lance 5 projecting into the reforming vessel and being adjustable in vertical direction. It will be seen that although the nozzle of downwardly directed lance 5 is located above the upper level of the molten metal, nevertheless, oxygen gas will be blown into the interior of the molten metal mass- The thus introduced oxygen gas will assure the refining of the prereduced material and the excess heat of the refining reaction will bring about the melting of the pellets to thus form a mixture of refined metal and at least part of which is transformed by the oxygen jet into a slagmetal foam which passes by overfiowing into portion 6 of the refining vessel in which the two phases, namely the slag and the molten steel, are allowed to separate into a continuous metal phase and a slag phase fioating thereon.
- the molten steel is then removed through an opening 7 located in the bottom of vessel portion 6, while the supernatant slag flows
- pellets of pulverulent prereduced products which are introduced into the left hand or refining portion of refining vessel 2 are preheated, prior to introduction into the vessel 2, preferably to a temperature of about 700 C.
- raw steel having a temperature of 1600 C. and the following composition:
- a lance 11 is provided in the vicinity of lance 5 for the purpose of introducing into refining vessel 2 a suspesnion of a mixture of prereduced steel-forming material in form of pulverulent sponge iron and of thermogenic material the latter consisting, for instance, of a mixture of pulverulent coke and pulverulent ferrosilicon containing 90% silicon.
- lance 11 could be used in the arrangement of FIG. 1 to introduce separately the thermogenic material in pulverulent form, and that any combination of introducing means of the prereduced material and thermogenic material is possible.
- pulverulent coke could be introduced through lance 11 and ferrosilicon in grains and prereduced ore through hopper 1.
- An additional lance serves for introducing oxygen into the interior of vessel 2, again above the reacting mass of prereduced material, for the purpose of causing at least partial co1nbustion of combustible refining gases emanating from the molten turbulent metal mass in the left hand portion of the refining vessel.
- Pulverulent sponge iron which is introduced into the left hand of refining vessel 2. is preheated, prior to the introduction in the vessel, preferably to a temperature of about 750 C. and has the following composition.
- the gases which escape from the refining vessel and which are subjected to partial combustion by means of the oxygen from lance 10 have a temperature of 1600 C. and consist of 21.9% CO2 and 78.1% CO.
- a method of continuously producing steel comprising the steps of continuously introducing into a refining vessel containing a mass of molten steel and slag a solid prereduced steel-forming material at an elevated temperature below the melting point of said material; simultaneously and continuously introducing thermogenic material and gaseous oxygen respectively in such amounts into the refining vessel and the molten mass therein so that the amount of thermogenic material by exothermic reaction with the oxygen will insure melting of the simultaneously and continuously introduced steel-forming material and that the amount of the simultaneously introduced oxygen is sutlicient to convert the continuously introduced prereduced steel-forming material into steel to thus obtain in the vessel a mixture of molten steel and slag, said gaseous oxygen being introduced in a jet from above into the material in the refining vessel to transform at least part of the mixture in said refining vessel into a metal-slag foam; and continuously withdrawing by overfiow said metal-slag foam from said metal refining vessel at such a rate that the amount of molten mass in said refining vessel remains
- thermogenic material is selected from the group consisting of carbon, ferrophosphorus, ferrosilicon and ferroaluminum.
- thermogenic material is coke
- thermogenic material is continuously introduced into the refining vessel admixed to said prereduced material.
- thermogenic material is continuously introduced into said refining vessel in the form of a pulverulent suspension thereof in a carrier gas.
- thermogenic material in pulverulent form suspended therein is blown in a jet from above into said mass of molten material in said refining vessel.
- thermogenic material insufficient amount to provide the heat necessary for the melting of said pellets and for their transformation into steel.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Powder Metallurgy (AREA)
Description
, B88881969 J. RAGUIN mL 3,486,882
CONTINUOUS STEEL MAKING PROCESS Dec. 30,"- 1969 v J, RAGUiN ET Af.' 3,-4865882 CONTINUOUS STEEL MAKING PROCSS Filed July 23, 1968 2 Sheets-Sheet 2 f ll United States Patent O Inf. C1. czlc /00, 7/00 U.S. Cl. 75-51 15 Claims ABSTRACT OF THE DISCLOSURE A method for continuously producing steel in which a solid prereduced steel-forming material is continuously introduced into a refining vessel containing molten steel and slag while simultaneously and continuously introducing thermogenic material and gaseous oxygen in such amounts into the refining vessel and the molten mass therein that the amount of thermogenic material by exothermic reaction with the oxygen will insure melting of the introduced prereduced solid steel-forming material and the amount of gaseous oxygen is sufficient to convert said prereduced steel-forming material into steel to thus obtain in the vessel a mixture of molten steel and slag. The gaseous oxygen is introduced into the vessel from above in form of a jet so as to transform part of the mixture into a metal-slag foam which is continuously withdrawn by overow from the reuing vessel at such a rate that the amount of molten mass therein remains substantially constant.
CROSS-REFERENCES TO RELATED APPLICATIONS The present application is a continuation-in-part application of the application Ser. No. 515,807, filed Dec. 12, 1965 and now abandoned.
BACKGROUND OF THE INVENTION The present invention relates to a process of making steel and, more particularly, the present invention is concerned with a process of making steel which requires only one melting of the steel-forming raw material.
The present invention is specifically concerned with making steel from prereduced, solid, steel-forming `material.
It is an object of the present invention to produce liquid steel in a continuous manner from prereduced solid, steel-forming material.
It is a further object of the present invention to produce steel from such prereduced, solid, steel-forming rnaterials in a simple economical manner.
Other objects and advantages of the present invention will become apparent from a further reading of the description and of the appended claims, and it will be noted that according to the present invention iron ore may be converted into steel without requiring the intermediate production of pig iron.
SUMMARY OF THE INVENTION With the above and other objects in view, the present invention relates to a method yof continuously producing steel comprising the steps of continuously introducing into a refining vessel, containing a mixture of molten steel-forming materials, a solid prereduced steel-forming ice material at an elevated temperature below the melting point of the prereduced material, simultaneously and continuously introducing thermogenic material and gaseous oxygen respectively in such amounts into the refining vessel and the molten `mass therein so that the amount of thermogenic material by exothermic reaction with the oxygen will insure melting of the simultaneously and continuously introduced steel forming material and that the amount of the simultaneously introduced oxygen is sufficient to convert the continuously introduced prereduced steel-forming material into steel to thus obtain in the vessel a mixture of molten steel and slag. The gaseous oxygen is introduced in a jet from above into the mixture in the refining vessel to transform at least part of the mixture in the refining vessel into a metal-slag foam, and continuously withdrawing by overflow the metalslag foam from the refining vessel at such a rate that the amount of molten mass in the refining vessel remains substantially constant.
Within the context of the present specification and claims, the term prereduced solid material is intended to denote iron ores which have been submitted to a reducing treatment such that between about 40 and 100% of the bound oxygen of the iron ore will have been removed by means of reducing agents such as, for instance, carbon. If for the purpose of producing the prereduced solid material an excess amount of carbon or the like is applied, such excess amount may be retained in the prereduced solid material which is introduced into the refining vessel. The other components of the iron ore and such also of the prereduced solid material may vary greatly.
Process of manufacturing such prereduced solid materials are yvell known in the art and are described for instance in a publication of CECA (Communaute Europeenne Charbon Acier), entitled Etude bibliographique des Procedes de reduction directe des minerais de fer, dated December 1960. Therein, the DLM, Freeman, Wiberg and Finsider processes are described.
The term thermogenic materials is to be understood, in the context of the present specification and claims, as denoting materials which react in an exothermic manner with oxygen or oxidizing substances. The amount of thermogenic material which is to be simultaneously introduced with the prereduced solid material, in accordance with the present invention, must be such that the heat requirements of the process are supplied by the heat `provided by the enthalpy of the prereduced material, which depends on the temperature at which the prereduced material is introduced into the refining vessel (which temperature preferably will be an elevated temperature below the melting point of the prereduced material), the enthalpy of the thermogenic material and the heat formed by oxidation of the same, and the combustion heat of gases which are oxidized during the refining process, primarily the combustion of CO into CO2.
Elements which form part of the thermogenic material and which may be oxidized in an exothermic reaction include, for instance, carbon, silicon and phosphorus.
The heat which is thus made available must be sufiicient to balance the thermic losses which correspond to the enthalpy of the slag, the enthalpy of the Withdrawn molten steel, the enthalpy of the gases, and other thermic losses due to radiation, etc.
According to various preferred embodiments of the present invention, the above described process may comprise one or more of the following features:
(a) Prereduced steel-forming material may be introduced in the form of pellets, generally having a size of between 2 and 40 mm. and preferably between l0 and 20 mm.
(b) The solid prereduced steel-forming material may be introduced in pulverulent form, for instance having a particle size of between microns and 2 mm. and preferably having a particle size between 100 microns and l (c) The prereduced solid steel-forming material may be sponge iron and, preferably, the particle size of the sponge iron may be greatly reduced and a pulverulent mass of sponge iron introduced into the refining vessel.
(d) A strongly thermogenic material such as, for instance, coke may be additionally, simultaneously with the prereduced material, and continuously introduced into the refining vessel.
(e) The solid prereduced steel-forming material and the thermogenic material may be jointly introduced into the refining vessel in the form of a mixture of these two types of materials.
(f) The thermogenic material may be introduced pneumatically in pulverulent form, for instance in the form of a pulverulent suspension of thermogenic material in a suitable carrier gas.
(g) At least `a portion of the gas produced during the refining process within the molten metal mass in the relining vessel may be oxidized and burned by reaction with a portion of the oxygen introduced into the molten metal, before the gas reaches the upper level of the mass of molten metal in the refining vessel.
It will be understood, that the process of the present invention is primarily concerned with a method of directly refining prereduced solid steel-forming materials which are introduced in hot condition into a refining vessel wherein the prereduced solid materials are changed into a liquid melt. These prereduced steel-forming materials may contain, in addition to iron, tbermogenic elements such as carbon, phosphorus or silicon in amounts sufficient to provide, upon reaction of these thermogenic materials with oxygen, in part or fully the heat necessary for the melting of the material and for transformation of the same into steel. If the amount of thermogenic materials contained in the prereduced solid material does not suffice for creating the amount of heat required for the process then, as described further above, thermogenic materials are additionally introduced into the refining vessel.
It is preferred according to the present invention to introduce the predeuced, solid steel-forming material into the refining vessel, and into the molten steel bath contained therein, in the form of pellets which, due to their geometrical shape, are particularly suitable for being introduced in a regular and controllable fiow so that within given time periods the same amounts of prereduced, solid steel HY forming material are introduced into the refining vessel.
According to another preferred embodiment, the prereduced, solid, steel-forming material is introduced in pulverulent form, by being blown into the refining vessel suspended in a hot reducing gas. This is particularly advantageous if the prereduced material is obtained in pulverulent form, for instance by iluidization processes known, per se, to those skilled in the art. The hot reducing gas serving as carrier for the pulverulent, prereduced, steel-forming material may also be derived from the waste gas leaving the refining vessel.
The present invention also contemplates, as discussed further above, the simultaneous introduction of solid, strongly thermogenic materials, which, for instance may be carbon in the form of coke or graphite, phosphorus in the form of ferrophosphorus, silicon in the form of ferrosilicon and aluminum in the form of ferroaluminum.
It is also within the scope of the present invention to reach a portion of the refining gas which develops in the metal bath immediately, and prior to escape of such refining gas from the metal bath, with oxygen so as to convert the refining gas to carbon dioxide, since thereby the heat content of the molten metal bath may be significantly increased.
The novel features which are considered as characteristic for the inventionl are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings in which the drawing is a schematic elevational view of an apparatus for carrying out the present invention.
The invention will now be described by way of the following example with reference to the drawing without, however, limiting the invention to the specific details of the example.
BRIEF DESCRIPTION OF THE DRAWING FIG. l is a schematic view showing an 'arrangement for carrying out the method of the present invention; and
FIG. 2 is a view of an embodiment thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing, reference numeral 1 indicates a heat insulated hopper made of refractory bricks and containing a relatively small amount of prereduced, hot, solid, steel-forming pellets which are introduced into hopper 1 in a continuous manner from a conventional pelletizing device (not shown). The pellets may be produced in any conventional manner and producing of the pellets does not form part of the present invention.
From hopper 1, the mass of pellets is then continuously and evenly introduced through a refractory conduit 3 into a continuous refining vessel 2 containing molten steel in its lower portion. The rate of introduction of pellets into a refining vessel 2 is controlled by means of a conventional, revolving distributor wheel 4.
A stream of oxygen under pressure having pulverulent lime suspended therein is introduced into refining vessel 2 from above in form of a jet through lance 5 projecting into the reforming vessel and being adjustable in vertical direction. It will be seen that although the nozzle of downwardly directed lance 5 is located above the upper level of the molten metal, nevertheless, oxygen gas will be blown into the interior of the molten metal mass- The thus introduced oxygen gas will assure the refining of the prereduced material and the excess heat of the refining reaction will bring about the melting of the pellets to thus form a mixture of refined metal and at least part of which is transformed by the oxygen jet into a slagmetal foam which passes by overfiowing into portion 6 of the refining vessel in which the two phases, namely the slag and the molten steel, are allowed to separate into a continuous metal phase and a slag phase fioating thereon. The molten steel is then removed through an opening 7 located in the bottom of vessel portion 6, while the supernatant slag flows through an opening 8 in the side Wall of vessel portion 6.
The pellets of pulverulent prereduced products which are introduced into the left hand or refining portion of refining vessel 2 are preheated, prior to introduction into the vessel 2, preferably to a temperature of about 700 C.
and have the following composition:
Percent Fe, metallic 73.8 Fe, total 80.8 CaO 0.45 SiO2 3.6 MgO 1.8 A1203 0.9
10.0 Miscel. (P205, MnO) 0.35
118 standard cubic meters of oxygen carrying suspended therein 117 kg. of pulverulent lime, are blown into the refining portion of refining vessel 2 through lance 5 per 1000 kg. of prereduced, solid steel-forming material.
In this manner, raw steel is obtained having a temperature of 1600 C. and the following composition:
Percent 0.040 0.005
Thereby, an amount of 270 kg. of slag is formed per 1000 kg. of prereduced steel-forming pellets, which slag has the following composition:
C P S M According to FIG. 2 a lance 11 is provided in the vicinity of lance 5 for the purpose of introducing into refining vessel 2 a suspesnion of a mixture of prereduced steel-forming material in form of pulverulent sponge iron and of thermogenic material the latter consisting, for instance, of a mixture of pulverulent coke and pulverulent ferrosilicon containing 90% silicon.
It is obvious that the lance 11 could be used in the arrangement of FIG. 1 to introduce separately the thermogenic material in pulverulent form, and that any combination of introducing means of the prereduced material and thermogenic material is possible. For instance pulverulent coke could be introduced through lance 11 and ferrosilicon in grains and prereduced ore through hopper 1.
The gases which are formed in refining vessel 2, and particularly in the portion thereof into which lances 5 and 11 extend, are withdrawn through ue 9. An additional lance serves for introducing oxygen into the interior of vessel 2, again above the reacting mass of prereduced material, for the purpose of causing at least partial co1nbustion of combustible refining gases emanating from the molten turbulent metal mass in the left hand portion of the refining vessel.
Pulverulent sponge iron which is introduced into the left hand of refining vessel 2. is preheated, prior to the introduction in the vessel, preferably to a temperature of about 750 C. and has the following composition.
The gases which escape from the refining vessel and which are subjected to partial combustion by means of the oxygen from lance 10 have a temperature of 1600 C. and consist of 21.9% CO2 and 78.1% CO.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can 'by applying current knowkledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential-characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to lbe comprehended within the meaning and range of equivalence of the following claims. Y
What is claimed as new and desired to be secured hy Letters Patent is set forth in the appended claims:
1. A method of continuously producing steel comprising the steps of continuously introducing into a refining vessel containing a mass of molten steel and slag a solid prereduced steel-forming material at an elevated temperature below the melting point of said material; simultaneously and continuously introducing thermogenic material and gaseous oxygen respectively in such amounts into the refining vessel and the molten mass therein so that the amount of thermogenic material by exothermic reaction with the oxygen will insure melting of the simultaneously and continuously introduced steel-forming material and that the amount of the simultaneously introduced oxygen is sutlicient to convert the continuously introduced prereduced steel-forming material into steel to thus obtain in the vessel a mixture of molten steel and slag, said gaseous oxygen being introduced in a jet from above into the material in the refining vessel to transform at least part of the mixture in said refining vessel into a metal-slag foam; and continuously withdrawing by overfiow said metal-slag foam from said metal refining vessel at such a rate that the amount of molten mass in said refining vessel remains substantially constant.
2. A method as defined in claim 1, wherein said metal slag foam is withdrawn into a decanting vessel and including the steps of causing in said decanting vessel separation of said metal-slag foam into a continuous metal phase and a slag phase fioating thereon, and separately discharging in the slag phase and the continuous metal phase from said decanting vessel.
3. A method as defined in claim 2, wherein said thermogenic material is selected from the group consisting of carbon, ferrophosphorus, ferrosilicon and ferroaluminum.
4. A method as defined in claim 3, wherein said thermogenic material is coke.
5. A method as defined in claim 3, wherein said thermogenic material is continuously introduced into the refining vessel admixed to said prereduced material.
6. A method as defined in claim 3, wherein said thermogenic material is continuously introduced into said refining vessel in the form of a pulverulent suspension thereof in a carrier gas.
7. A method as defined in claim 6, wherein said carrier gas with said thermogenic material in pulverulent form suspended therein is blown in a jet from above into said mass of molten material in said refining vessel.
8. A method as defined in claim 2, wherein said solid prereduced material is continuously introduced into said refining vessel in the form of pellets.
9. A method as defined in claim 8 wherein said pellets contain thermogenic material insufficient amount to provide the heat necessary for the melting of said pellets and for their transformation into steel.
10. A method as defined in claim 2, wherein said solid prereduced material is in pulverulent form.
11. A method as defined in claim 2, wherein said solid prereduced material is sponge iron.
12. A method as defined in-fclaim 2, wherein oxidiza- Ible gas is formed during transformation of said solid prereduced material into steel, andfwherein at least a portion of said oxidizable gas is reacted with oxygen while still below the upper level of said mass of molten steel in said refining vessel.
A method as defined in claim 2, whffrpin combustible gas is formed during transformation of said solid prereduced material into steel, and wherein at least part of said combustible material is reacted with oxygen while still'below the upper level of said mass of molten steel in said refining vessel, Iand wherein the amount of oxygen introduced into said refining vessel is sufiicient to oxidize said thermogenic material and said portion of said cornbustible gas.
14. A method as defined in claim 2, wherein said jet of gaseous oxygen is introduced into said refining vessel through a lance orifice located in said refining vessel directed towards and upwardly spaced from said mass of molten steel.
15. A method as defined in claim 14, wherein said distance of said lance orifice from said molten lmass of material in said refining vessel is adjustable.
(References on following page) References Cited UNITED STATES PATENTS Halley 75-52 Morrill 75-*60 X Kalling et al. 75-51 X Madaras 75-43 X Muller et a1 75-60 8 L. DEWAYNE RUTLEDGE, Primary Examiner G. K. WHITE, Assistant Examiner U.S. Cl. X.R.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR999972A FR1427201A (en) | 1964-12-24 | 1964-12-24 | Manufacture of steel from pre-reduced products |
Publications (1)
Publication Number | Publication Date |
---|---|
US3486882A true US3486882A (en) | 1969-12-30 |
Family
ID=8845551
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US753336*A Expired - Lifetime US3486882A (en) | 1964-12-24 | 1968-07-23 | Continuous steel making process |
Country Status (6)
Country | Link |
---|---|
US (1) | US3486882A (en) |
BE (1) | BE674132A (en) |
DE (1) | DE1458879A1 (en) |
ES (1) | ES321105A1 (en) |
FR (1) | FR1427201A (en) |
GB (1) | GB1095880A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3617257A (en) * | 1967-03-13 | 1971-11-02 | Inst Derecherches De Lasiderur | Process for continuously refining metal |
US3725044A (en) * | 1968-12-07 | 1973-04-03 | Mitsubishi Metal Corp | Method of continuous processing of sulfide ores |
EP0074270A1 (en) * | 1981-09-07 | 1983-03-16 | British Steel Corporation | Process and apparatus for continuous steel-making |
US5301620A (en) * | 1993-04-01 | 1994-04-12 | Molten Metal Technology, Inc. | Reactor and method for disassociating waste |
US5555822A (en) * | 1994-09-06 | 1996-09-17 | Molten Metal Technology, Inc. | Apparatus for dissociating bulk waste in a molten metal bath |
US5733358A (en) * | 1994-12-20 | 1998-03-31 | Usx Corporation And Praxair Technology, Inc. | Process and apparatus for the manufacture of steel from iron carbide |
US11912608B2 (en) | 2019-10-01 | 2024-02-27 | Owens-Brockway Glass Container Inc. | Glass manufacturing |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1514381A (en) * | 1967-01-13 | 1968-02-23 | Soc Metallurgique Imphy | Process and installation for the reductive melting of scrap iron, powders, or iron sponge |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2889219A (en) * | 1956-12-28 | 1959-06-02 | Inland Steel Co | Control method and apparatus for iron ore reduction process |
US2962277A (en) * | 1958-05-15 | 1960-11-29 | Gen Electric | Apparatus for continuous process of steel making |
US2978318A (en) * | 1957-07-15 | 1961-04-04 | Stora Kopparbergs Bergslags Ab | Method of producing steel from pulverulent iron products rich in carbon |
US3153588A (en) * | 1960-07-21 | 1964-10-20 | Julius D Madaras | Method of melting sponge iron |
US3356490A (en) * | 1964-05-04 | 1967-12-05 | Centre Nat Rech Metall | Refining pig iron |
-
1964
- 1964-12-24 FR FR999972A patent/FR1427201A/en not_active Expired
-
1965
- 1965-12-21 BE BE674132D patent/BE674132A/xx unknown
- 1965-12-22 DE DE19651458879 patent/DE1458879A1/de not_active Withdrawn
- 1965-12-23 GB GB54734/65A patent/GB1095880A/en not_active Expired
- 1965-12-23 ES ES0321105A patent/ES321105A1/en not_active Expired
-
1968
- 1968-07-23 US US753336*A patent/US3486882A/en not_active Expired - Lifetime
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2889219A (en) * | 1956-12-28 | 1959-06-02 | Inland Steel Co | Control method and apparatus for iron ore reduction process |
US2978318A (en) * | 1957-07-15 | 1961-04-04 | Stora Kopparbergs Bergslags Ab | Method of producing steel from pulverulent iron products rich in carbon |
US2962277A (en) * | 1958-05-15 | 1960-11-29 | Gen Electric | Apparatus for continuous process of steel making |
US3153588A (en) * | 1960-07-21 | 1964-10-20 | Julius D Madaras | Method of melting sponge iron |
US3356490A (en) * | 1964-05-04 | 1967-12-05 | Centre Nat Rech Metall | Refining pig iron |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3617257A (en) * | 1967-03-13 | 1971-11-02 | Inst Derecherches De Lasiderur | Process for continuously refining metal |
US3725044A (en) * | 1968-12-07 | 1973-04-03 | Mitsubishi Metal Corp | Method of continuous processing of sulfide ores |
EP0074270A1 (en) * | 1981-09-07 | 1983-03-16 | British Steel Corporation | Process and apparatus for continuous steel-making |
US5301620A (en) * | 1993-04-01 | 1994-04-12 | Molten Metal Technology, Inc. | Reactor and method for disassociating waste |
US5555822A (en) * | 1994-09-06 | 1996-09-17 | Molten Metal Technology, Inc. | Apparatus for dissociating bulk waste in a molten metal bath |
US5733358A (en) * | 1994-12-20 | 1998-03-31 | Usx Corporation And Praxair Technology, Inc. | Process and apparatus for the manufacture of steel from iron carbide |
US11912608B2 (en) | 2019-10-01 | 2024-02-27 | Owens-Brockway Glass Container Inc. | Glass manufacturing |
Also Published As
Publication number | Publication date |
---|---|
BE674132A (en) | 1966-04-15 |
ES321105A1 (en) | 1966-07-16 |
FR1427201A (en) | 1966-02-04 |
DE1458879A1 (en) | 1971-03-18 |
GB1095880A (en) | 1967-12-20 |
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