Basf Aktiengesellschaft

Walter Goesele

Bruno Sander

Wolfgang Habermann

Klaus Hess

Guenther Huber

Rolf Klassen

Peter Lintz

Metal ions are removed from process wastewaters by using an electrically conducting, cathodically polarized filter-aid layer whose potential is at least 50 mV more negative than the redox potential of the metal ions to be removed, by passing the metal ion-containing water through the filter-aid layer and periodically renewing the filter-aid layer at intervals of from 2 to 180 minutes by backwashing, classifying and precoating processes.

Removal of metal ions from process wastewaters

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.

Dewatering of sewage sludges on chamber filter presses

Growing community of inventors

Heidelberg, Germany

Walter Goesele