Method for transforming slag derived from non-iron metallurgy
US6261340A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 15, 2000 |
| Grant date | Jul 17, 2001 |
| Priority date | — |
| Expiry date | Sep 15, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
In a method of converting slags derived from nonferrous metallurgy, in particular primary and secondary Ni and Cu metallurgical slags, while recovering and/or enriching the nonferrous metals and forming synthetic puzzolans, the molten oxidic slags are reduced with gases containing H.sub.2 and CO such as, e.g., cracked gas in a first reduction stage above a metal bath containing Cu and/or Ni and optionally Co. The redox potential of the CO/H.sub.2 mixture is reduced by adding 10 to 40% by volume H.sub.2 O vapor and/or CO.sub.2 in order to hold off the reduction of Fe oxides. Subsequently, the remaining slag free of Cu and Ni is further reduced above an iron bath while using carbon in order to reduce the portion of Fe oxides so as to produce a slag free of Fe and nonferrous heavy metals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.