Submerged membrane bioreactor for treatment of nitrogen containing water
US6616843B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 30, 2001 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Aug 30, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W10/10
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A single tank submerged membrane bioreactor for treating feed water having unacceptable levels of ammonia or total nitrogen has both a membrane scouring bubble supply and an oxygenating bubble supply. The membrane scouring bubble supply continuously provides large scouring bubbles to clean the membranes. Permeate is continuously withdrawn from the membranes at a high rate but the large scouring bubbles do not transfer sufficient oxygen to the mixed liquor to create aerobic conditions in the reactor. The oxygenating bubble supply is operated to provide small bubbles of air or oxygen that intermittently produce aerobic conditions in a significant part of the mixed liquor. Alternating aerobic and anoxic conditions occur in a significant portion of the tank suitable for nitrification and denitrification. The level of dissolved oxygen (DO) or oxygen reduction potential (ORP) in the tank is measured by sensors and determines when the oxygenating bubble supply will be turned on or off between set minimum and maximum time limits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.