Patent · US Expired

Method and device for purifying wastewaters

US7175764B2 · kind B2 · utility

2Cited by

4References

20Claims

0Family size

Assignee

Papierfabrik August Koehler SE · DE

Inventors

Harald Kraft · Uhingen, DE
Hans-Thomas Armbruster · Altdorf bei Nürnberg, DE
Wendelin Benz · Renchen, DE

Key dates

Filing date	Oct 1, 2002
Grant date	Feb 13, 2007
Priority date	—
Expiry date	Oct 1, 2022

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY02W10/10
WIPO fieldEnvironmental technology
WIPO sectorChemistry

Abstract

The invention relates to a method for purifying wastewaters, particularly wastewaters produced in the paper industry, involving the following steps: a) aerobic clarification of the wastewater using activated sludge in an activation stage; b) carrying out, in a secondary settling tank, a subsequent clarification of a portion of the wastewater/activated sludge mixture leaving the activation stage; c) desiccating, in a desiccation unit, another portion of the wastewater/activated sludge mixture leaving the activation stage; d) returning at least a portion of the activated sludge removed in steps b) and c) into the activated sludge tank.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.