| Abstract: | Biological denitrification of nitrate-containing waste water and ground water. The differing objectives serve to distinguish processes for the treatment of waste water and those for the production of drinking water. In waste water purification, frequent use is made of submerged reactors with deposition and recycling of bacteria. The carbon compounds required by the bacteria are either present in the water or have to be added. If the nitrogen is present as ammonium in the waste water, then there are several different ways of combining nitrification and denitrification reactors. In production of drinking water, both heterotrophic and autotrophic bacteria are used. Since the bacteria are not allowed to enter the supply network, fixed reactors or other reactors with immobilised biomass are used. Sand bed filters are still necessary to retain compounds from the water after denitrification. |
