| 摘要 |
<p>PURPOSE:To provide a method for treating sewage which yields stable dephosphorization and denitrification efficiency in a short hydraulic retention time. CONSTITUTION:In a sewage treatment method with an active sludge, sludge separated from liquid in the final sedimentation vessel 2 is treated anaerobically in an anaerobic vessel 3 and, after being treated aerobically in an aerobic vessel 4, is returned to an aeration vessel 1 as return sludge. Since the separated sludge is alone subjected to dephosphorization etc., its hydraulic retention time can be shortened, stabilizing the dephosphorization efficiency.</p> |
