| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a wastewater treatment apparatus and a wastewater treatment method that can obtain a high nitrogen elimination rate while facilitating maintenance and causing no increase in manufacturing cost. <P>SOLUTION: The wastewater treatment apparatus C includes a primary treatment tank S1 introducing wastewater W0 and separating it into sludge H and raw water W1, and a secondary treatment tank S2 for the secondary treatment of the raw water W1, and is configured to eliminate nitrogen G1 in treated water W2 by returning a part of the treated water W2 after secondary treatment into the primary treatment tank S1 and bringing the returned treated water W2 into contact with the sludge H in the primary tank S1. A return pipe 30 allowing the treated water W2 after secondary treatment to flow through inside and to be returned into the primary treatment tank S1 is disposed in the primary treatment tank S1. The return pipe 30 is configured to arrange its tip near a bottom wall 9a in the primary treatment tank S1 and to allow the treated water W2 to flow out into the sludge H accumulated in the primary tank S1 from an outflow hole formed on the tip side. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
