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US20030164062A1 - Method relating to manufacturing of steel - Google Patents

Method relating to manufacturing of steel Download PDF

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Publication number
US20030164062A1
US20030164062A1 US10/204,215 US20421503A US2003164062A1 US 20030164062 A1 US20030164062 A1 US 20030164062A1 US 20421503 A US20421503 A US 20421503A US 2003164062 A1 US2003164062 A1 US 2003164062A1
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US
United States
Prior art keywords
gpi
furnace
added
iron
slag
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/204,215
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English (en)
Inventor
Per-Ake Lundstrom
Ake West
Marten Gornerup
Gunnar Andersson
Carl-Johan Rick
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Uvan Hagfors Teknologi AB
Original Assignee
Uvan Hagfors Teknologi AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
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Application filed by Uvan Hagfors Teknologi AB filed Critical Uvan Hagfors Teknologi AB
Assigned to UDDEHOLM TECHNOLOGY AKTIEBOLAG reassignment UDDEHOLM TECHNOLOGY AKTIEBOLAG ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ANDERSSON, GUNNAR, GORNERUP, MARTEN, LUNDSTROM, PER-AKE, RICK, CARL-JOHAN, WEST, AKE
Publication of US20030164062A1 publication Critical patent/US20030164062A1/en
Abandoned legal-status Critical Current

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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
    • C21C5/52—Manufacture of steel in electric furnaces
    • C21C5/527—Charging of the electric furnace
    • 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
    • C21C5/52—Manufacture of steel in electric furnaces
    • 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling

Definitions

  • the invention concerns a method relating to manufacturing of steel in an electric arc furnace, comprising melting charged steel raw materials for steel manufacturing.
  • DRI is manufactured through a number of different processes, among which Midrex-process is the dominating technique.
  • Midrex-process is the dominating technique.
  • Iron carbide Fe 3 C is another product, which to a limited degree is available as a substitute to scrap.
  • Table 1 shows the typical range of composition of DRI along with the data of Fe 3 C.
  • DRI/Fe 3 C materials are relatively high in carbon that results in CO (g) formation when oxygen is injected into the steel.
  • the CO (g) will reduce the steel nitrogen content and enhance slag foaming.
  • the consistence of the DRI/Fe 3 C composition with time enables the EAF operator to have a smooth process with small alterations between different heats. TABLE 1 Typical chemical composition of DRI and iron carbide.
  • pig iron A more readily available scrap substitute than DRI/Fe 3 C is pig iron.
  • pig iron is already today charged in many EAF:s, wherein the pig iron consists of conventional shapes produced in pig iron casting machine, sand lined pit casing or the like. These pig iron shapes, however, are not designed to fit the requirements of an EAF steel raw material very well, and particularly it does not promote the control of the melting and decarburisation and reduction processes which are carried out in the EAF.
  • FIG. 1 in the form of a diagram illustrates how the content of residual metals emanating from scrap can be reduced at the manufacturing of steel according to the invention
  • FIG. 2 and FIG. 3 in the form of diagrams illustrate the effects of pre-heating and post-combustion, respectively.
  • EAF Electro Arc Furnace
  • x-100 weight-% of charged steel raw materials for steel manufacturing consists of granulated pig iron, herein denominated GPI.
  • GPI satisfies the following requirements, namely:
  • raw iron granulate can be produced, in which at least 90 weight-% of the granulates consist of particles with shapes varying from substantially round or oval disks to drops and spheres with sizes varying from 1 mm up to 25 mm measured in the largest dimension of the granules.
  • the GPI can be used in this form, but preferably the fine fraction is removed by screening (this finer fraction can be used as a doping agent in a foaming slag in the EAF, as will be explained more in detail in the following), so that the GPI which in accordance with what is mentioned above is charged to form a melt an/or which is added to a form or remaining melt consists of a granulate which to at least 80 weight-% consists of particles having a particle size between 2 mm and 25 mm, measured in the largest dimension of the granules.
  • the low area/volume ratio of the round or oval particles of the GPI reduces oxidation during storage and handling, something which has turned out to be a problem with DRI with its porous structure.
  • the area/volume ratio of GPI is higher than of normal pig iron and large sized scrap material, and considerably more well defined, which provides a better and more reproducible heating and melting features.
  • the round or oval shape of the GPI also results in a relatively high bulk density, approximately 4.5 kg/l, with excellent free-flow characteristics. Most commercial scrap grades such as bundles, shred metal and turnings, have a bulk density of 0.7-1.2 kg/l, table 1.
  • the GPI's shape also enables easy penetration through the slag layer when the iron is injected into the EAF.
  • the EAF as a steel raw material for making steel
  • GPI also scrap containing impurities in the form of one or more of the metals which belong to the group of residual metals which consist of e.g. copper, nickel, molybdenum, and tin.
  • the GPI contains significant lower levels of residuals (Cu, Sn, Ni, etc.) than scrap, table 1.
  • the dilution effect of GPI addition to the EAF on the residual content is illustrated in FIG. 1.
  • the low residual levels of GPI opens for the possibility of the EAF operator to use poorer scrap quality, FIG. 1.
  • the addition of GPI amounts to at least 10%, preferably more than 25%, or even more than 40% of the added steel raw materials, the remaining steel raw material being substantially scrap.
  • GPI as the sole, 100% steel raw material can be contemplated, particularly when producing steel intended for flat products for which virgin steel raw material is particularly advantageous.
  • GPI has a higher content of carbon compared to scrap and DRI.
  • the CO (g) purging reduces the nitrogen level of the steel and chemical heat is generated.
  • the CO formation during oxygen injection may be used in order to form a foamy slag. If a carbon injection of 12 kg/ton steel is used during normal operation for this matter, approximately 30-40% of the charged material can be substituted by GPI only in order to balance the carbon injection.
  • An additional benefit of adding the carbon as GPI instead of injected carbon is the possibility of achieving an early boil, i.e. GPI opens for an early slag foaming, which increases the heat efficiency and eliminates any power reduction due to thermal overload.
  • the GPI chemical composition also differs with respect to some additional properties compared to scrap, DRI and Fe 3 C.
  • GPI has a very low oxide content.
  • DRI/Fe 3 C contains a rather large amount of gangue and unreduced iron oxides, which require additional energy to be added.
  • GPI is relatively high in silicon. This silicon is oxidised during melting and oxygen injection and requires an extra lime addition in order to control the slag composition. This lime requires extra energy input in order to heat and melt the slag former.
  • DRI directly reduced iron
  • DRI which contains in weight-% 75-90% metallic iron, 0.2-3% C, 2-7% gangue material, mainly SiO 2 +Al 2 O 3 , the balance being substantially iron oxide, FeO
  • GPI is added at least in an amount such that its content of silicon and carbon in combination with the carbon in added DRI will reduce the iron oxide in said DRI to form elementary iron, at the same time as the oxidation of silicon and carbon in said GPI and DRI generates heat to a sufficient degree for compensating the cooling effect that is caused by the gangue material and the iron oxide in added DRI and preferably also compensates for the cooling effect because of added lime or other basic slag former (Mg-
  • the GPI can be added through basket charging as well as by continuous feeding, e.g. via a vertical scrap chute or by injection.
  • the GPI should be added in the first basket that is charged in the EAF, wherein a melt is quickly formed because of the low melting temperature of the GPI.
  • the GPI addition may eliminate at least one basket of scrap. This will decrease the furnace idle time as well as heat losses.
  • continuous feeding of material into the EAF results in a much smoother operation of the furnace, compared to batch-wise addition of scrap.
  • foaming slag practice in combination with maximum power input can be applied.
  • the high bulk density of GPI also is an advantage when basket charging is used only.
  • Temperature control of the steel during melting also increases the possibilities of performing refining operations at an early stage in the furnace and it opens for the possibility of running the EAF semi-continuously, that is with a rather large hot heel, continuous feeding of steel raw material and batch-wise bottom tapping.
  • the CO (g) formed during slag foaming can be subject to post-combustion above the steel bath.
  • the GPI can be preheated by the furnace exhausts to high temperatures without any risk of environmentally hazardous emissions, which even more increases the heat efficiency of the furnace.
  • the energy needed for melting and heating is calculated on the material types shown in table 3. The calculations are based on the assumption that all C and Si are subject to oxidation, the CO formed is not post-combusted and all formation of SiO 2 during melting is assumed to be neutralised by the addition of CaO or other neutralizing agent. The energy required for melting of CaO or corresponding and the energy evolved when CaO, SiO 2 and other oxides are mixing, is assumed to be equal.
  • Table 3 also gives the theoretical energy requirement in order to melt and superheat the materials to a temperature of 1600° C. Given figures are per ton produced pure Fe. As can be seen from the table, GPI requires the lowest amount of electrical energy due to the latent chemical heat available in the material. It can also be understood from table 3 that the rather large difference between GPI # 1 and #2 is due to the difference in % Si; 0.5 and 1.2 respectively. TABLE 3 Material compositions and energy requirements for various materials when aiming at different slag basicities.
  • FIG. 2 presents a calculation of the energy need at different degrees of preheating for the table 3 materials. It should be noticed that the preheating of scrap is limited to 300° C. due to environmentally reasons. Preheating of DRI might also be restricted due to the pyrophoric behavior.
  • FIG. 3 shows the theoretical energy requirements versus the amount of post combusted CO (g) that forms CO 2 (g) (100% yield of produced heat). Added material is preheated to 200° C.
  • the invention is particularly suited to be employed for the manufacturing of steel in an EAF (Electric Arc Furnace) comprising the formation of a foaming top slag with a temperature of 1400-1800° C. in the furnace on top of the surface of the molten metal and supply of oxygen gas to the molten metal in order to oxidise at least part of the existing silicon in the melt for heat generation and to oxidise at least part of the carbon in the melt for heat generation and to generate gas in the form of CO and/or CO 2 which contributes to the slag foaming, by which the supply of oxygen to the melt also brings about oxidation of metal elements other than silicon in the melt, in this text generally referred to as valuable metal elements, which go into the slag and are reduced there by the addition of reduction agents to the top slag so that these elements to a considerable degree are recovered to the melt.
  • EAF Electro Arc Furnace
  • a doping agent in the form of a particle-formed, granulated product is added to the top slag with the aim of creating improved conditions for the reduction of the oxidised, valuable metal elements in the top slag, participating in the reduction process itself, contributing to and/or maintaining the slag foaming as well as adding metal to the melt, said doping agents fulfilling the following requirements, namely:
  • the said doping agent is of the same general type that is used as a steel raw material and which is melted to form a bath of molten metal as has been described in the foregoing.
  • the GPI which is added as a doping agent to the slag, has a smaller particle size than the GPI that is added as a steel raw material to the furnace according to the foregoing. More particularly, it is advantageous to use, as doping agent, GPI which to at least 80 weight-% consists of particles having a particle size varying between 0.5 mm and 5.5 mm measured in the largest dimension of the particles.
  • the doping agent thus may consist of a fine fraction of granulated pig iron, the main part of the granulate having a considerably larger particle size, 2-25 mm, being basket charged to the furnace or injected into the melt that is successively formed.
  • a granulate having said smaller particle sizes has a capacity to penetrate the slag to a desired degree and to keep themselves suspended in the slag for sufficiently long not only to melt, which the particles do quite quickly, but also in order that the content of carbon and silicon of the granulate shall get sufficient time to react with the oxides of the valuable metal elements in the slag, and successively agglomerate to form larger agglomerate of molten metal, which sink down through the slag to combine with the melt.
  • the addition of doping agent can be made through a lance with a gas carrier, where the lance can be placed through the slag door, furnace wall or furnace roof, or by mechanical feeding from a position above the slag, in the furnace wall or furnace roof.
  • the added doping particles melt quickly in the hot slag and form small drops with large boundary layer area between liquid metal phase and slag, which kinetically favours reduction of metallic oxides.
  • the doping agent contains active contents of dissolved carbon and silicon, which participate as melted drops in the reduction reactions. Dissolved carbon forms CO/CO 2 -gas, which in turn generates and/or maintains the foaming slag and helps to keep the small metal drops suspended in the slag.
  • the carbon dissolved in the doping agent has several functions: it contributes to and/or maintains formation of the foaming slag, it contributes to keeping the small molten metal drops suspended in the slag, which maintains the foaming, and it participates in the reduction processes.
  • the silicon which is dissolved in the doping agent, has several functions. Silicon contributes to the reduction of oxidized valuable metal elements, which most probably decreases the boundary layer tension between slag and doping agent, which further accelerates the reduction reaction. Furthermore, heat is formed through the oxidation of dissolved carbon and silicon. Oxidation of dissolved silicon contributes as well to the formation of slag in the furnace. Finally, the doping agent contributes to a significant addition of iron to the melt when most of the reduction agents—C and Si—in the doping agent have reacted with the slag and a number of smaller drops have agglomerated to larger drops which then sink down through the slag layer into the metal bath.
  • the contents of carbon and silicon in the doping agent be kept within relatively narrow limits within the stated outer limits.
  • the contents of carbon and silicon should not vary more than +/ ⁇ 0.5%, preferably not more than +/ ⁇ 0.3% from the assigned target value within said outer limits.
  • the carbon content in the doping agent should go up to (C x +/ ⁇ 0.5)%, where C x is a number between 3 and 4.5.
  • the carbon content should be (C x +/ ⁇ 0.3)%.
  • the silicon content should be (Si x +/ ⁇ 0.5)%, preferably (Si x +/ ⁇ 0.3)%, where Si x is a number between 1 and 2.5.
  • the desired contents of carbon and silicon can be obtained through alloying the raw iron with carbon and silicon after possible desulphurisation or other treatment of the raw iron.
  • the amount of added doping agent can be varied within wide limits depending on the composition of the melt, the composition of the doping agent and other factors. Normally the amount of doping agent added to the slag according to the invention can go up to between 5 and 60 kg of doping agent per ton produced steel, which is added to the slag by injection into the slag or in another manner to maintain slag foaming and reduction. Simultaneously, oxygen is added in a balanced amount to the steel to oxidize mainly Si and C in the steel to obtain heat and gas for the slag foaming. Also other metal elements in the steel, e.g. Fe and Cr, are oxidized to a certain degree and then reduced again when they reach the slag.
  • reduction agents may also be added, besides the doping agent according to the invention, e.g. C or Si, to the slag in order to ensure the reduction together with the doping agent according to the invention.
  • the reduction agent e.g. C or Si
  • the reduction agent completely consists of the doping agent of the invention, which is advantageous from several reasons.
  • the doping agent of the invention has evident economical merits; on the other hand the process is easier to control if the number of different additions is restricted.
  • the GPI which is employed according to the invention, in the first place for forming a bath of molten metal, which GPI is basket charged or is injected in the melt, as well as the GPI which possibly is injected as a doping agent in connection with foamed slag practice, can be manufactured according to a number of different methods, comprising granulation of a pig iron melt having the above mentioned composition, comprising disintegration of a stream of molten metal to drops, which are cooled in a water bath to form a granulate.
  • a useful technique, which is known under the trade name GRANSHOT is as mentioned described in the U.S. Pat. No.
  • 3,888,956 which also describes how the size and shape of the granulate that is being manufactured can be controlled through variation of the height of fall of the stream of molten metal before the stream is disintegrated to drops and/or of the height of fall of the drops before they hit the water surface in the cooling bath.
  • the achieved granulate may be a sieved for the provision of the desired size fraction or desired size fractions, respectively, according to above.
  • GPI as a charging material, i.e. as a steel raw material—in which above mentioned doping agent is not included—in EAFs, the following applies, which can be utilised according to different aspects of the invention:
  • GPI replaces completely or partly other steel raw materials, such as for example scrap, conventional pig iron, DRI and/or Fe 3 C, and can according to an aspect of the invention be charged through the use of scrap baskets and/or equipment for continuous charging.
  • GPI has very good preheating features, especially for preheating by the flues from the furnace because of the shape and chemical stability of the GPI, which is taken advantage of according to another aspect of the invention, which characterised in that the GPI that is charged in the furnace is preheated by the flue (exhaust) gases of the furnace before charging.
  • This possibility does not exist with scrap, at least not to the same degree, because of the shape of scrap and also because of the risk of formation of dioxine, or with DRI because of the pyrophorous character of that material
  • GPI has good “free flow” features, which facilitates continuous charging, which can be employed according to an other aspect of the invention.
  • a plurality of essential advantages can be gained, such as
  • GPI has a high bulk density, which is an advantage during all phases of the handling of the material, from transportation to charging.
  • GPI has low melting point ( ⁇ 1350° C.) which gives an early metal melt in the furnace, a possibility which is also utilised according to a number of further aspects of the invention, which are described in the foregoing, in the appending patent claims and/or below.
  • the oxidation of C and Si in GPI means a very low consumption of energy for melting GPI, wherein the heat which is generated through the oxidation of C and Si also can be used as a contribution to melting any possibly added scrap, and/or DRI and/or for compensating for heat losses because of reduction of iron oxide in any possibly added DRI, addition of lime or other basic slag former for controlling the basicity of the slag, etc.
  • Law contents of residuals (Cu, Sn, Zn, Ni, etc.) which according to an aspect of the invention can be utilised e.g. for diluting the content of such residual elements in the molten metal, when also scrap is used as a steel raw material in the charge.
  • GPI is used as a charging material, preferably in the form of a coarse fraction of a pig iron granulate according to above (80 weight-% of the GPI having particle sizes between 2 and 25 mm), as well as a doping agent in foaming slag, preferably in the form of a fine fraction of pig iron granulate (80 weight-% having sized between 0.5 and 5.5 mm).
  • a C-and Si-buffer is ensured in the melt. If the charging of GPI to the melt further is performed continuously, the oxidation of alloying elements is further diminished. This creates conditions for valuable metals, in the first place iron and possibly other existing, oxidised metals to be recovered by reduction through addition of only GPI in its function as a doping agent to the slag for securing a complete slag reduction.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Manufacture And Refinement Of Metals (AREA)
US10/204,215 2000-02-17 2001-02-13 Method relating to manufacturing of steel Abandoned US20030164062A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE0000510-8 2000-02-17
SE0000510A SE517296C2 (sv) 2000-02-17 2000-02-17 Sätt vid tillverkning av stål i ljusbågsugn under användande av granulerat tackjärn

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US20030164062A1 true US20030164062A1 (en) 2003-09-04

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US (1) US20030164062A1 (fr)
EP (1) EP1261747A1 (fr)
AU (1) AU2001232571A1 (fr)
SE (1) SE517296C2 (fr)
WO (1) WO2001061056A1 (fr)
ZA (1) ZA200206543B (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025059230A1 (fr) * 2023-09-11 2025-03-20 Suncoke Technology And Development Llc Unités métalliques granulées à faible teneur en soufre, et systèmes, dispositifs et procédés associés

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ITUA20163986A1 (it) * 2016-05-31 2017-12-01 Tenova Spa Metodo ed apparato per la produzione di ghisa, ghisa prodotta secondo detto metodo
CN111893239B (zh) * 2020-09-02 2021-10-19 北京科技大学 利用直接还原法结合电炉双渣法冶炼高磷铁精矿的工艺
WO2025037617A1 (fr) * 2023-08-16 2025-02-20 日本製鉄株式会社 Procédé de fusion de sources de fer

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US4101313A (en) * 1975-10-14 1978-07-18 Institut De Recherches De La Siderurgie Francaise (Irsid) Process and apparatus for the production of steel
US5471495A (en) * 1991-11-18 1995-11-28 Voest-Alpine Industrieanlagenbeau Gmbh Electric arc furnace arrangement for producing steel
US5611838A (en) * 1993-12-10 1997-03-18 Voest-Alpine Industrieanlagenbau Gmbh Process for producing an iron melt
US6689189B1 (en) * 1998-09-03 2004-02-10 Uddeholm Technology Aktiebolag Metallurgical product

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FR2753205B1 (fr) * 1996-09-12 1998-12-04 Usinor Sacilor Procede pour realiser un laitier moussant au-dessus d'un acier inoxydable en fusion dans un four electrique
AT405054B (de) * 1997-06-18 1999-05-25 Voest Alpine Ind Anlagen Verfahren und anlage zum herstellen einer eisenschmelze unter einsatz von eisenhältigen hüttenwerksreststoffen
JPH11344287A (ja) * 1998-04-01 1999-12-14 Nkk Corp アーク炉操業方法

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US4101313A (en) * 1975-10-14 1978-07-18 Institut De Recherches De La Siderurgie Francaise (Irsid) Process and apparatus for the production of steel
US5471495A (en) * 1991-11-18 1995-11-28 Voest-Alpine Industrieanlagenbeau Gmbh Electric arc furnace arrangement for producing steel
US5611838A (en) * 1993-12-10 1997-03-18 Voest-Alpine Industrieanlagenbau Gmbh Process for producing an iron melt
US6689189B1 (en) * 1998-09-03 2004-02-10 Uddeholm Technology Aktiebolag Metallurgical product

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2025059230A1 (fr) * 2023-09-11 2025-03-20 Suncoke Technology And Development Llc Unités métalliques granulées à faible teneur en soufre, et systèmes, dispositifs et procédés associés
WO2025059233A1 (fr) * 2023-09-11 2025-03-20 Suncoke Technology And Development Llc Unités métalliques granulées à faible teneur en carbone, systèmes, dispositifs et procédés associés
WO2025059239A1 (fr) * 2023-09-11 2025-03-20 Suncoke Technology And Development Llc Traitement d'unités métalliques granulées dans des fours à arc électrique, systèmes et procédés associés
US12370599B2 (en) 2023-09-11 2025-07-29 Suncoke Technology And Development Llc Treating cooling water in iron production facilities, and associated systems, devices, and methods
US12397346B2 (en) 2023-09-11 2025-08-26 Suncoke Technology And Development Llc Low-sulfur granulated metallic units
US12403529B2 (en) 2023-09-11 2025-09-02 Suncoke Technology And Development Llc Use of a basic oxygen furnace to produce granulated metallic units, and associated systems, devices, and methods
US12420335B2 (en) 2023-09-11 2025-09-23 Suncoke Technology And Development Llc Low-carbon granulated metallic units
US12427569B2 (en) 2023-09-11 2025-09-30 Suncoke Technology And Development Llc Continuous granulated metallic units production, and associated systems, devices, and methods
US12465973B2 (en) 2023-09-11 2025-11-11 Suncoke Technology And Development Llc Use of residual iron within granulated metallic unit production facilities, and associated systems, devices, and methods

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Publication number Publication date
WO2001061056A1 (fr) 2001-08-23
SE0000510L (sv) 2001-08-18
AU2001232571A1 (en) 2001-08-27
SE0000510D0 (sv) 2000-02-17
SE517296C2 (sv) 2002-05-21
EP1261747A1 (fr) 2002-12-04
ZA200206543B (en) 2003-04-10

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