[go: up one dir, main page]

EP0019087B1 - Matières de désulfuration pour bains de fonte et d'acier ainsi que procédé pour leur fabrication - Google Patents

Matières de désulfuration pour bains de fonte et d'acier ainsi que procédé pour leur fabrication Download PDF

Info

Publication number
EP0019087B1
EP0019087B1 EP80101985A EP80101985A EP0019087B1 EP 0019087 B1 EP0019087 B1 EP 0019087B1 EP 80101985 A EP80101985 A EP 80101985A EP 80101985 A EP80101985 A EP 80101985A EP 0019087 B1 EP0019087 B1 EP 0019087B1
Authority
EP
European Patent Office
Prior art keywords
weight
calcium oxide
less
size
temperatures
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.)
Expired
Application number
EP80101985A
Other languages
German (de)
English (en)
Other versions
EP0019087A1 (fr
Inventor
Albert Braun
Willi Dr. Portz
Georg Dr. Strauss
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.)
Hoechst AG
Original Assignee
Hoechst AG
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
Publication date
Application filed by Hoechst AG filed Critical Hoechst AG
Priority to AT80101985T priority Critical patent/ATE4227T1/de
Publication of EP0019087A1 publication Critical patent/EP0019087A1/fr
Application granted granted Critical
Publication of EP0019087B1 publication Critical patent/EP0019087B1/fr
Expired legal-status Critical Current

Links

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
    • C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
    • C21C7/04—Removing impurities by adding a treating agent
    • C21C7/064—Dephosphorising; Desulfurising
    • C21C7/0645—Agents used for dephosphorising or desulfurising
    • 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
    • C21C1/00—Refining of pig-iron; Cast iron
    • C21C1/02—Dephosphorising or desulfurising
    • C21C1/025—Agents used for dephosphorising or desulfurising

Definitions

  • the present invention relates to desulfurizing agents for pig iron and steel melts based on a calcium carbide containing calcium oxide and to processes for their production.
  • carbide calcium carbide
  • lime calcium oxide
  • additives in the form of a mixture consisting of lime and fluorspar are added to the melt of a relatively high-percentage carbide, the grain size of the additives being less than 20 mm, preferably 0.5 to 10 mm, and their adhesive and crystal water content less than 5 % By weight, preferably less than 0.5% by weight.
  • carbide which has 20 to 55% by weight CaC 2 and a high CaO content of more than 45 to 80% by weight, is more suitable for desulfurizing hot metal and steel melts, especially then , if it was manufactured in a certain way, and that the relatively expensive fluorspar as an additive can also be dispensed with.
  • the desulfurizing agent according to the invention is obtained by heating calcium carbide melt in an existing and customarily produced manner, which already has a calcium oxide content of up to 45% by weight, at temperatures up to 2000.degree. preferably pre-heated to 1100 ° C, finely divided calcium oxide, in an excess of 3 to 15 wt .-%, based on the amount desired in the end product.
  • the temperature of the preheating is chosen to be higher, the higher the proportion of additionally dissolved calcium oxide between 45 and 80% by weight in the end product.
  • the mixture obtained is then solidified to temperatures of 350 to 450 ° C. and pre-broken at these temperatures to grain sizes smaller than 150 mm.
  • the inevitably occurring grain fraction smaller than 4 mm is then separated from the remaining product and the latter is crushed to exclude moisture by breaking and grinding to grain sizes smaller than 10 mm.
  • the product according to the invention is an excellent desulfurization agent for low-carbon pig iron and steel melts and is characterized by an increased desulfurization yield based on calcium carbide.
  • a calcium carbide melt is preferably used, which contains between 20 and 45% by weight of CaO.
  • the portions smaller than 4 mm which have been screened off after the preliminary crushing essentially consist of CaO and can be returned to the process as finely divided calcium oxide, where, together with fresh CaO, they serve as the starting product.
  • Calcium carbide e.g. produced electrothermally, the lime-coke mixture in the Möller being adjusted to a weight ratio of 100:40, which corresponds to a carbide with a CaO content of approx. 40% by weight.
  • CaO with a grain size of 3 to 8 mm and a Ca (OH) 2 and CaCO 3 content of less than 1 each is preheated to a temperature of about 1100 ° C. in the jet of the molten carbide, which has been tapped from the furnace into a crucible %
  • a total CaO content of 62.5% by weight results in the crucible, which corresponds to an excess of 4% by weight, based on that in the finished end product desired content of 60 wt .-% CaO.
  • the fractions of less than 4 mm obtained during preliminary crushing essentially contain the CaO used in excess, while the product with grain sizes larger than 4 mm remains an intensive mixture of 40% by weight CaC 2 and 60% by weight CaO, which then in the usual way smaller on grain sizes is ground as 10 mm.
  • the screened grain fraction smaller than 4 mm is used together with fresh lime as a starting product.
  • 1800 kg of the product worked up and ground according to the invention are used for the desulfurization of 300,000 kg of a steel melt with a sulfur content of 0.02% by weight at 1650 ° C.
  • the sulfur content of the melt is reduced to less than 0.005% by weight.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (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)
  • Treatment Of Steel In Its Molten State (AREA)
  • Heat Treatment Of Steel (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)

Claims (5)

1. Agent de désulfuration pour bains de fonte brute et d'acier à base d'un carbure de calcium contenant de l'oxyde de calcium, préparé par introduction dans un bain de carbure de calcium existant présentant une teneur en oxyde de calcium allant jusqu'à 45% en poids, d'oxyde de calcium en fines particules et préchauffé à des températures allant jusqu'à 2000 °C, en excès de 3 à 15% en poids, par rapport à la quantité de CaO recherchée dans le produit fini, la température de préchauffage étant choisie d'autant plus élevée que la proportion d'oxyde de calcium supplémentaire dissous dans le produit fini doit être plus élevée entre 45 et 80% en poids, puis refroidissement du mélange obtenu avec solidification à des températures de 350 à 450 °C, concassage grossier à ces températures en morceaux de granulométrie inférieure à 150 mm, séparation de la fraction granulométrique de moins de 4 mm obligatoirement formée du produit restant et fractionnement de ce dernier à l'abri de l'humidité par concassage et broyage en particules d'une granulométrie inférieure à 10 mm.
2. Procédé de préparation d'un agent de désulfuration pour bains de fonte brute et d'acier à base d'un carbure de calcium contenant de l'oxyde de calcium, caractérisé en ce que, pour l'obtention d'un produit fini contenant 20 à 55% en poids de carbure de calcium et plus de 45 à 80% en poids d'oxyde de calcium, on introduit, dans un bain de carbure de calcium existant présentant déjà une teneur en oxyde de calcium allant jusqu'à 45% en poids, de l'oxyde de calcium en fines particules et préchauffé à des températures allant jusqu'à 2000 °C en excès de 3 à 15% en poids, par rapport à la quantité recherchée dans le produit fini, la température de préchauffage étant choisie d'autant plus élevée que la proportion d'oxyde de calcium supplémentaire dissous dans le produit fini doit être plus élevée entre 45 et 80% en poids, on refroidit ensuite le mélange obtenu avec solidification à des températures de 350 à 450 °C, on le concasse grossièrement à ces températures en morceaux de dimensions inférieures à 150 mm, on sépare la fraction granulométrique de moins de 4 mm obligatoirement formée du produit restant et on fractionne ce dernier à l'abri de l'humidité par concassage et broyage en particules d'une granulométrie inférieure à 10 mm.
3. Procédé selon la revendication 2, caractérisé en ce que l'on effectue l'addition de l'oxyde de calcium dans un creuset.
4. Procédé selon la revendication 2 ou 3, caractérisé en ce que l'on part d'un bain de carbure de calcium contenant de l'oxyde de calcium en proportion comprise entre 20 et 45% en poids.
5. Procédé selon l'une des revendications 2 à 4, caractérisé en ce que l'on recycle dans le procédé les fractions de granulométrie inférieure à 4 mm séparées par tamisage après le concassage grossier.
EP80101985A 1979-05-14 1980-04-14 Matières de désulfuration pour bains de fonte et d'acier ainsi que procédé pour leur fabrication Expired EP0019087B1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT80101985T ATE4227T1 (de) 1979-05-14 1980-04-14 Entschweflungsmittel fuer roheisen- und stahlschmelzen sowie ein verfahren zu ihrer herstellung.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19792919324 DE2919324A1 (de) 1979-05-14 1979-05-14 Entschweflungsmittel fuer roheisen- und stahlschmelzen sowie ein verfahren zu ihrer herstellung
DE2919324 1979-05-14

Publications (2)

Publication Number Publication Date
EP0019087A1 EP0019087A1 (fr) 1980-11-26
EP0019087B1 true EP0019087B1 (fr) 1983-07-20

Family

ID=6070655

Family Applications (1)

Application Number Title Priority Date Filing Date
EP80101985A Expired EP0019087B1 (fr) 1979-05-14 1980-04-14 Matières de désulfuration pour bains de fonte et d'acier ainsi que procédé pour leur fabrication

Country Status (9)

Country Link
US (1) US4323392A (fr)
EP (1) EP0019087B1 (fr)
JP (1) JPS55158212A (fr)
AT (1) ATE4227T1 (fr)
CA (1) CA1141964A (fr)
DE (2) DE2919324A1 (fr)
ES (1) ES491528A0 (fr)
NO (1) NO153108C (fr)
ZA (1) ZA802836B (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0061011A1 (fr) * 1981-03-24 1982-09-29 Hoechst Aktiengesellschaft Procédé pour la fabrication d'agents de désulfuration de fonte ou d'acier fondus
EP0061012A1 (fr) * 1981-03-24 1982-09-29 Hoechst Aktiengesellschaft Procédé pour la fabrication d'agents de désulfuration de fonte et d'acier fondus
EP0387580A1 (fr) * 1989-03-13 1990-09-19 Hoechst Aktiengesellschaft Agent et procédé de désulfuration de métaux en fusion

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2920353A1 (de) * 1979-05-19 1980-11-27 Hoechst Ag Verfahren zur herstellung von entschweflungsmitteln fuer roheisen- oder stahlschmelzen
ES497686A0 (es) * 1979-12-29 1981-11-01 Hoechst Ag Procedimiento para la preparacion de un agente para la de- sulfuracion de masas fundidas metalicas
DE2952686A1 (de) * 1979-12-29 1981-07-02 Hoechst Ag, 6230 Frankfurt Verfahren zur herstellung von entschwefelungsmitteln fuer roheisen- oder stahlschmelzen

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1935567B2 (de) * 1969-07-12 1971-05-13 Knapsack AG, 5033 Hurth Knapsack Verfahren zur herstellung von calciumkarbid bestimmter qualitaet
DE1919414B2 (de) * 1969-04-17 1977-07-14 Hoechst Ag, 6000 Frankfurt Verfahren und vorrichtung zum abkuehlen von in gefaesse abgestochenem calciumcarbid

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3666445A (en) * 1967-12-26 1972-05-30 Kaiser Ind Corp Auxiliary composition for steel-making furnaces
DE1758250B1 (de) * 1968-04-29 1971-10-28 Sueddeutsche Kalkstickstoff Mittel zum Entschwefeln von Eisenschmelzen
DE2037758C3 (de) * 1970-07-30 1979-08-02 Hoechst Ag, 6000 Frankfurt Verfahren zur Herstellung von CaIciumkarbid zur Entschwefelung von Metallschmelzen
JPS554811B2 (fr) * 1973-06-13 1980-02-01
DE2741588C2 (de) * 1977-09-15 1985-02-07 Skw Trostberg Ag, 8223 Trostberg Mittel zum Entschwefeln von Eisenschmelzen

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1919414B2 (de) * 1969-04-17 1977-07-14 Hoechst Ag, 6000 Frankfurt Verfahren und vorrichtung zum abkuehlen von in gefaesse abgestochenem calciumcarbid
DE1935567B2 (de) * 1969-07-12 1971-05-13 Knapsack AG, 5033 Hurth Knapsack Verfahren zur herstellung von calciumkarbid bestimmter qualitaet

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0061011A1 (fr) * 1981-03-24 1982-09-29 Hoechst Aktiengesellschaft Procédé pour la fabrication d'agents de désulfuration de fonte ou d'acier fondus
EP0061012A1 (fr) * 1981-03-24 1982-09-29 Hoechst Aktiengesellschaft Procédé pour la fabrication d'agents de désulfuration de fonte et d'acier fondus
EP0387580A1 (fr) * 1989-03-13 1990-09-19 Hoechst Aktiengesellschaft Agent et procédé de désulfuration de métaux en fusion

Also Published As

Publication number Publication date
ZA802836B (en) 1981-06-24
NO153108C (no) 1986-01-15
JPS6353244B2 (fr) 1988-10-21
ATE4227T1 (de) 1983-08-15
ES8101121A1 (es) 1980-12-16
US4323392A (en) 1982-04-06
NO153108B (no) 1985-10-07
NO801420L (no) 1980-11-17
ES491528A0 (es) 1980-12-16
DE2919324A1 (de) 1980-12-04
DE3064206D1 (en) 1983-08-25
JPS55158212A (en) 1980-12-09
EP0019087A1 (fr) 1980-11-26
CA1141964A (fr) 1983-03-01

Similar Documents

Publication Publication Date Title
CH619679A5 (en) Process for producing abrasive materials
EP0061012B1 (fr) Procédé pour la fabrication d'agents de désulfuration de fonte et d'acier fondus
EP0019087B1 (fr) Matières de désulfuration pour bains de fonte et d'acier ainsi que procédé pour leur fabrication
DE2731521A1 (de) Verfahren zur herstellung von ferromolybdaenlegierungen
DE1963128A1 (de) Verfahren zum Reinigen und Agglomerieren von Pyritabbraenden
EP0019086B1 (fr) Procédé pour la fabrication d'agents de désulfurisation de fonte ou d'acier fondus
DE1667734B2 (de) Verfahren zur herstellung von getrennten, nicht-staubenden, fliessfaehigen schwefelteilchen
EP0031552B1 (fr) Agent de désulfuration et procédé pour sa fabrication
DE2913207C2 (de) Kalkhaltiges Mittel zum Behandeln von Eisenschmelzen
EP0031534B1 (fr) Procédé pour la fabrication d'agents de désulfuration de fonte ou d'acier fondus
DE2037758A1 (en) Calcium carbide for desulphurisation - of molten metals improved by treatment with quick lime and fluorspar
DE2952761A1 (de) Entschwefelungsmittel fuer roheisen- und stahlschmelzen sowie ein verfahren zu ihrer herstellung
EP0012832B1 (fr) Procédé d'hydrofugeage de scories de haut-fourneau
EP0438838A2 (fr) Procédé de fabrication d'un ciment et d'un granulat à base de laitier d'acier de convertissseur, et dispositif de granulation
EP0061011B1 (fr) Procédé pour la fabrication d'agents de désulfuration de fonte ou d'acier fondus
DE2048203C3 (de) Gießhilfsmittel zur Verwendung beim Gießen von Metall
DE2344324A1 (de) Verfahren zur behandlung schwefelhaltiger schlacke und nach diesem verfahren hergestelltes erzeugnis
DE69005178T2 (de) Verfahren zur Herstellung einer hydraulisch abbindenden Substanz und die mittels diesem Verfahren erhaltene Substanz.
DE1813220A1 (de) Verfahren zur Granulierung von pulverartigen Materialien
DE896561C (de) Verfahren zur Behandlung von Schlacken
DE2139575A1 (de) Formsand
DE2705543A1 (de) Verfahren zur erzeugung von schlacken mit gesteigert loeslichem phosphatanteil
DE2050511B2 (de) Verfahren zur herstellung von schweisshilfsstoffen
DE1085804B (de) Verfahren zur Herstellung von Silikatformkoerpern fuer Bauzwecke
DE2327719A1 (de) Verfahren zur herstellung von tabletten, briketts oder pellets aus metallischem eisen

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): AT BE DE FR GB IT LU NL SE

17P Request for examination filed

Effective date: 19810401

ITF It: translation for a ep patent filed
GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): AT BE DE FR GB IT LU NL SE

REF Corresponds to:

Ref document number: 4227

Country of ref document: AT

Date of ref document: 19830815

Kind code of ref document: T

REF Corresponds to:

Ref document number: 3064206

Country of ref document: DE

Date of ref document: 19830825

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
ITTA It: last paid annual fee
EPTA Lu: last paid annual fee
EAL Se: european patent in force in sweden

Ref document number: 80101985.2

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19990223

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19990226

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19990311

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: LU

Payment date: 19990406

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: BE

Payment date: 19990408

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19990415

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19990419

Year of fee payment: 20

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: NL

Payment date: 19990429

Year of fee payment: 20

BE20 Be: patent expired

Free format text: 20000414 *HOECHST A.G.

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20000413

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: NL

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20000414

Ref country code: LU

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20000414

Ref country code: AT

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20000414

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY

Effective date: 20000429

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

Effective date: 20000413

NLV7 Nl: ceased due to reaching the maximum lifetime of a patent

Effective date: 20000414

EUG Se: european patent has lapsed

Ref document number: 80101985.2