| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a biological treatment method of wastewater which can efficiently reduce and remove nitrogen and selenium in wastewater by improving the selenium reducing capacity of activated sludge. <P>SOLUTION: The biological treatment method comprises a first anaerobic treatment process (6) for bringing the wastewater (1) into contact with activated sludge adhering to a carrier in presence of first organic matter (5) under an anaerobic condition, and a second anaerobic treatment process (8) for bringing the treated water of the first anaerobic treatment process (6) into contact with activated sludge adhering to a carrier in presence of second organic matter (7) under an anaerobic condition. This method may additionally contain a solid-liquid separation process (10) for performing the solid-liquid separation of the treated water of the second anaerobic treatment process (8), a first aerobic treatment process (2) for bringing the wastewater into contact with activated sludge adhering to a carrier under an aerobic condition before introducing the wastewater to the first anaerobic treatment process (6), and a second aerobic treatment process (13) for bringing the treated water (14a) of the second anaerobic treatment process or the separated water (11) of the solid-liquid separation process into contact with activated sludge adhering to a carrier under an aerobic condition. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
