Process for the thermal decomposition of metal sulphates

US5271919A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gunter Lailach · Krefeld, DE
• Rudolf Gerken · Krefeld, DE

Key dates

• Filing date: Jul 12, 1991
• Grant date: Dec 21, 1993
• Expiry date: Jul 12, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/129
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process for the thermal decomposition of metal sulphate mixtures at temperatures from 800.degree. to 1100.degree. C. under oxidizing conditions, in which the metal sulphate mixtures are mixed with roasting residue and reacted together with fuels in the decomposition reactor to form roasting residue and SO.sub.2 -containing gases from roasting wherein the roasting residue admixed with the sulphate mixture is the finely divided fraction of the resulting roasting residue which is separated from the stream of gas in an electrostatic gas purification apparatus and returned to the decomposition reactor. This procedure has an advantageous influence on the formation of coarse roasting residue and also significantly reduces the proportion of undecomposed, water soluble sulphates in the roasting residue.