Method for the continuous or discontinuous extraction of a metal or several metals from a slag that contains the metal or a compound of the metal

US8157884B2 · kind B2 · utility

Assignee

• SMS SIEMAG AG · DE

Inventors

• Rolf Degel · Ratingen, DE
• Jürgen Kunze · Rutesheim, DE

Key dates

• Filing date: Oct 25, 2007
• Grant date: Apr 17, 2012
• Expiry date: Mar 14, 2028

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P10/25
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

The invention concerns a method for the continuous or discontinuous extraction of a metal or several metals from a slag that contains the metal or a compound of the metal, in which the liquefied metal-containing slag is heated in a primary or secondary smelting unit (1). To provide an improved method for extracting metals, especially copper, from slags, the invention provides that the metal-containing slag is heated in a primary or secondary smelting unit (1) designed as an alternating-current electric furnace, and the molten material is then fed from the primary or secondary smelting unit (1) into a furnace (2) designed as a direct-current electric furnace, in which the metal to be extracted is subjected to an electrolytic separation, where a reducing agent in the form of calcium silicide (CaSi), calcium carbide (CaC2), ferrosilicon (FeO), aluminum (Al), and/or reducing gases is added and/or injected into the primary or secondary smelting unit (1).