Patent · US Expired

Method for purifying process water or wastewater containing wood resin

US5354479A · kind A · utility

2Cited by

5References

9Claims

0Family size

Assignee

Eka Nobel AB · SE

Inventors

Magnus Wretborn · Stenungsund, SE
Arne Andersson · Mölnlycke, SE
Gunnar Goransson · Göteborg, SE

Key dates

Filing date	Apr 30, 1993
Grant date	Oct 11, 1994
Priority date	—
Expiry date	Apr 30, 2013

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S210/928
WIPO fieldEnvironmental technology
WIPO sectorChemistry

Abstract

Wood-resin-containing process water or wastewater from the pulp industry is purified by adding, as flocculants, a high-molecular-weight polyethylene oxide and a water-soluble, non-ionic cellulose ether, suitably having a flocculation temperature of 35.degree.-80.degree. C. The added amount per liter of water is preferably 2-20 mg of the high-molecular-weight polyethylene oxide and preferably 5-30 mg of the non-ionic cellulose ether.

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