| 摘要 |
<p>In the process, water containing organic carbon, ammonium and nitrate is biologically purified. In a first reaction vessel (10), forming a denitrifying biofilm reactor, the majority of the carbon is eliminated under partly anoxic, partly aerobic conditions with utilisation of nitrate oxygen or molecular oxygen. In a second, aerated reaction vessel (20), the ammonium is at least partly converted into nitrates by nitrifying organisms. Nitrate-containing water is returned from the second reaction vessel to the first. The water to be treated is conducted in the first reaction vessel from top to bottom over a flooded fixed bed. To supplement a deficiency of nitrate oxygen in the carbon elimination, the solid bed is aerated in the bottom region with a gas which contains a metered portion of molecular oxygen. The process according to the invention is particularly suitable for the purification of waste water (effluent) which has a variable ammonium concentration. <IMAGE></p> |
