High-rate biological waste water treatment process using activated sludge recycle
US4867883A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 1988 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Jun 13, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/906
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A high-rate biological waste water treatment process for removing organic tter, phosphorus and nitrogen nutrients from municipal waste water comprising the steps of mixing the influent waste water in an initial anaerobic reactor zone to maintain the biological solvents in suspension with a denitrified mixed liquor from a downstream anoxic reactor zone, typically at a flow rate of 0.5 to two times the waste water flow rate. The reactor zone serves to select microorganisms capable of accumulating quantities of phosphorus in excess of that required for simple cell growth and reproduction. The phosphorus removal occurs due to the removal of excess sludge (waste activated sludge) produced in the process wherein such sludge can be removed from the clarifier underflow or as a mixed liquor directly from the biological reactor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.