Foam separation method for reducing AOX, COD, and color bodies of kraft pulp bleach plant effluents
US5670020A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1995 |
| Grant date | Sep 23, 1997 |
| Priority date | — |
| Expiry date | Jun 1, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/928
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The invention described in the specification relates to a process and apparatus for reducing AOX, COD and color bodies from the filtrate streams generated by a kraft pulp bleaching sequence. The method involves vigorously mixing an F.sub.D filtrate with an F.sub.E filtrate to form a filtrate mixture and treating the filtrate mixture with a coagulating compound, a flocculating compound and recycled foam concentrate. After chemically treating the filtrate mixture, the mixture is foamed with air in order to capture floc which formed in the mixture. Concentration of the foam and recycle of the foam to the filtrate mixture has been found to significantly increase the concentration of and reduce the amount of solids generated in the treatment system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.