Patent · US Expired

Method of removing macromolecular organic dissolved and colloidal material from wood processing industry effluents

US4842688A · kind A · utility

3Cited by
4References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 18, 1987
Grant dateJun 27, 1989
Priority date
Expiry dateNov 18, 2007

Classification

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

Abstract

A method of removing macromolecular organic dissolved and colloidal compounds from the effluents of a paper and cellulose mill by using waste sludge containing fibers and chemicals. The sludge is acidified to a pH of approx. 2 by a mineral acid prior to adding into the effluent. Organic material is precipitated with fibers in a sedimentation vessel at a pH of 4.5-6.

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