Patent · US Expired

Method and apparatus for desulphurizing iron with minimal slag formation

US5466275A · kind A · utility

3Cited by
2References
12Claims
0Family size

Inventor

Key dates

Filing dateAug 29, 1994
Grant dateNov 14, 1995
Priority date
Expiry dateAug 29, 2014

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21C7/064
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

The invention relates to a method and apparatus for desulphurizing iron with minimal slag formation, comprising the steps of melting and heating, to a temperature of about 1400.degree. to 1800.degree. C., a slag having the following chemical composition: PA1 20% max SIO.sub.2 ; PA1 30% max/Al.sub.2 O.sub.3 ; PA1 about 5-40% SiO.sub.2 +Al.sub.2 O.sub.3 +TiO.sub.2 combined; PA1 2% max FeO; PA1 1.5% max MnO; PA1 about 25-65% CaO+MgO+BaO+Na.sub.2 O+K.sub.2 O; PA1 20% max MgO; PA1 10% max Na.sub.2 O+K.sub.2 O; PA1 60% max CaF.sub.2 ; PA1 about 50-85% CaO+MgO+BaO+Na.sub.2 O+K.sub.2 O+CaF.sub.2 ; percentages by weight; where the ratio of the percentage by weight of CaO plus MgO divided by the percentage by weight of SiO.sub.2 plus one-half Al.sub.2 O.sub.3 is at least two and where the ratio of the percentage by weight of Na.sub.2 O plus K.sub.2 O to SiO.sub.2 is no more than one; then mixing the sulphur-containing hot metal with this bath of molten slag so as not to exceed 10 parts molten iron per part slag by weight. The desulphurized molten iron is then drawn from beneath the slag bath. The process may be accomplished using a low shaft furnace according to the present invention compris…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.