| 摘要 |
<p>PURPOSE:To efficiently remove nitrogen, by sending waste water containing org. nitrogen to a first reaction tank without diluting the same and not only holding liquid temp. to 40-50 deg.C but also adjusting the concn. of dissolved oxygen to perform aeration treatment. CONSTITUTION:Waste water is sent into a first reaction tank 5 from a line 4 in an undiluted state and the decompositional removal of org. nitrogen by bacteria is performed in the presence of air blown in from a blower 6. Subsequently, this treated liquid is sent to a second reaction tank 7 to promote the propagation of a protozoan in the presence of air blown in from the blower 8 to allow the protozoan to efficiently prey up bacteria and fragments of activated sludge flocs. This treated liquid is successively sent to a sedimentation tank 10 where separated into supernatant water and sedimented sludge and supernatant water is discharged as treated water while sedimented sludge is successively withdrawn from the bottom part and a part thereof is returned to the second reaction tank 7 as return sludge.</p> |
