Method for treating wastewater in a membrane bioreactor to produce a low phosphorus effluent
US6946073B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 2, 2003 |
| Grant date | Sep 20, 2005 |
| Priority date | — |
| Expiry date | Sep 2, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/906
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
Removal of biological nutrients from a wastewater yielding a low phosphorous (e.g., less than 0.25 mg/L) output includes providing a serial multistage bioreactor containing activated sludge having in hydraulic series an anaerobic zone and a downstream aerobic zone, with each zone having an upstream inlet and a downstream outlet. The wastewater is provided to the anaerobic zone inlet. A quantity of chemical sufficient to precipitate soluble and particulate phosphorous is added to the downstream aerobic zone in an amount sufficient to yield a low phosphorous output. Treated water is separated from the activated sludge and precipitated phosphorous and a return activated sludge separated from the treated water is recycled to the anaerobic zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.