Process for the biological purification of water
US5520812A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 1993 |
| Grant date | May 28, 1996 |
| Priority date | — |
| Expiry date | Sep 17, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/903
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
In the process, water, in which organic carbon, ammonium and nitrate are contained, is biologically purified. In a first reaction vessel (10) forming a denitrifying biofilm reactor the carbon is to a large extent eliminated under partly anoxic, partly aerobic conditions by the use of nitrate-containing oxygen, and molecular oxygen respectively. In a second, ventilated reaction vessel (20) the ammonium is converted at least partially by nitric bacteria into nitrates. Water containing nitrates is recirculated from the second into the first reaction vessel. In the first reaction vessel the water to be treated is conveyed from the top to the bottom via a flooded fixed bed. To supplement a deficiency in nitrate-containing oxygen in the elimination of carbon the fixed bed is ventilated in the base region with a gas which contains a metered amount of molecular oxygen. The process according to the invention is particularly suitable for the purification of waste water having a variable ammonium concentration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.