| 摘要 |
<p>After water to be treated is biologically treated, when flocculation treatment is performed by adding a flocculant for removing a dissolved material or a suspended material such as a fungus body or a biological metabolite in the thus-biologically treated water, the treated water having a good quality is obtained with a reduced amount of the flocculant being used. There is provided a wastewater treatment apparatus having a biological reaction tank 1 for biologically treating water to be treated, a flocculation reaction tanks 2A, 2B for conducting a flocculation reaction by adding a flocculant to the thus-biologically treated water flowing from the biological reaction tank 1, and a dissolved air flotation separation tank 3 for performing solid-liquid separation on the water subjected to a flocculation treatment flowing from the flocculation reaction tank 2B. An aeration unit is provided in the flocculation reaction tank 2A and, then, by performing aeration stirring, not only a flocculation ability is enhanced, but also a dissolved air flotation separation ability in the latter step is improved.</p> |
