| 摘要 |
<p>PURPOSE:To remove an org. substance and phosphorus with high efficiency, by packing an iron filter material as a contact filter material alone or as a main material and performing recirculation aeration treatment so that the load of phosphorus to the surface area of the iron filter material is made at 1g/m<2>.day or less. CONSTITUTION:Sewage enters the aeration chamber 4 partitioned by the partition wall 3 of a contact filter material tank 2 from an inlet pipe 1 and enters the contact filter material tank 2 along with recirculated sewage by the air lift effect of air bubbles blown off from an air diffusion pipe 5. The sewage is passed through a contact filter material 6 to be recirculated and aerated to treat the org. substance in the sewage while bacteria are deposited and grown on the surface of the contact filter material. The treated water subjected to recirculation contact aeration is discharged from a treated water discharge port 7 or introduced into a sedimentation tank before being discharged. An iron filter material is mainly used as said contact filter material 6 and sewage is recirculated and aerated so that the load of phosphorus to the surface area of the iron filter material is set to 1.0g/m<2>.day or less.</p> |
