Patent · US Expired

Method for removing chrome and/or nickel from liquid slags

US6855189B2 · kind B2 · utility

4Cited by
4References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 18, 2001
Grant dateFeb 15, 2005
Priority date
Expiry dateMar 27, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02W30/50
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

In a method for removing chromium oxide and nickel oxide, and combinations thereof, from liquid slags or slag mixtures, in which the liquid slag is A charged onto a metal bath, in particular an iron bath, and reduced by feeding carbon or carbon carriers, the carbon feed into the metal bath is effected until a decrease of the Cr and/or Ni oxide contents of the slag to a value of between 0.8 wt.-% and 0.2 wt.-%. As the pregiven Cr and/or Ni oxide content range of the slag is reached, reductants having higher reduction potentials such as, e.g., Al, Ca, Si, Fe—Si or Ca—Si are added in order to lower the Cr and/or Ni oxide contents to below 0.15 wt.-%, preferably below 0.08 wt.-%.

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