Dewatering of sewage sludges on chamber filter presses

US4411797A · kind A · utility

Assignee

• BASF SE

Inventors

• Bruno Sander · Ludwigshafen, DE
• Klaus Hess
• Peter Lintz · Heidelberg, DE
• Walter Goesele · Bischofswerda, DE

Key dates

• Filing date: Oct 2, 1981
• Grant date: Oct 25, 1983
• Expiry date: Oct 2, 2001

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01D37/04
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A process for dewatering sewage sludges, the dewatering characteristics of which have been improved by adding an organic flocculant, on a chamber filter press, wherein the greater part of the water in the flocculated sludges is removed by gravity filtration in a process step upstream of the chamber filter press, without application of a pressure difference, and the actual pressure filtration, on the chamber filter press, is only then carried out. In principle, commercial products can be used as the organic flocculant. These are water-soluble, macromolecular compounds which have been obtained by polymerization or copolymerization of acrylamide, acrylic cid and/or their salts, or of esters of acrylic acid or methacrylic acid with specifically modified alcohol components.