| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a sewage treatment method and a treatment apparatus therefor which remarkably reduce the amount of generated surplus sludge, and have no influence on the quality of treated water. <P>SOLUTION: The sewage treatment apparatus comprises an aeration tank 2 for biologically treating sewage, a sedimentation tank 3 for performing the solid-liquid separation of the biologically treated sewage to obtain treated water and return sludge, a means for pulling out a part of the return sludge to obtain sludge, an alkali treatment tank 8 for treating the pulled-out sludge with alkali, a solubilization tank 9 for solubilizing the alkali-treated sludge in a second solubilization process, a biological solubilization tank 10 for biologically solubilizing the solubilized sludge under an anaerobic, anoxic or microaerophilic condition in a third solubilization process, and sludge return piping 12 for returning the solubilized sludge to the biological treatment system. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
