| 摘要 |
The objective of the present invention is to provide a waste water treatment device that does not generate excess sludge. The present invention is a biological waste water treatment device characterized in having a pretreatment tank (X) and at least one biodegradation and digestion tank (A) provided with an air diffuser (da), a fixed filter bed for aerobic microorganisms (ae), and a fixed filter bed for anaerobic microorganisms (an), and having the fixed filter bed for anaerobic microorganisms (an) arranged below the fixed filter bed for aerobic microorganisms (ae). It is preferred that this device have a plurality of biodegradation and digestion tanks (A) disposed in series and that the disposed number thereof be 2 to 10. This device preferably has an inflow port provided to an upper part of the biodegradation and digestion tank (A) in order to allow treatment water to flow from the prior-stage pretreatment tank (X) or biodegradation and digestion tank (A) into the biodegradation and digestion tank (A), and an outflow port provided to the deepest part of the biodegradation and digestion tank (A) in order to allow treatment water to flow out to a later-stage post treatment tank (Y) or biodegradation and digestion tank (A). |
