Wastewater biological phosphorus removal process
US5480548A · kind A · utility
45Cited by
5References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1993 |
| Grant date | Jan 2, 1996 |
| Priority date | — |
| Expiry date | Dec 28, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/906
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The present invention relates to a process for treating wastewater utilizing a step feed return activated sludge process. The wastewater is directed via one or more step feed points through a mainstream process. The step feed point includes at least one aerobic zone and at least one anoxic zone, in repeating or alternating sequence. A portion of effluent from the one or more anoxic zones are fed through at least one anaerobic zone to which raw or pretreated wastewater is fed and returned to the upstream portion of the anoxic zone. Additionally, return activated sludge may be recycled to one or more of the anoxic zones.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.