| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a wastewater treatment apparatus which can reduce the volume of a biological reaction tank by aerobically digesting activated sludge to be returned to the biological reaction tank without addition of carriers, enabling a size reduction of the whole apparatus and reduction of construction costs. <P>SOLUTION: The wastewater treatment apparatus comprises the biological reaction tank 12 which mixes raw water with the activated sludge to perform purification treatment, a solid-liquid separation means (a final settling basin 13) which performs the solid-liquid separation of the activated sludge-containing liquid treated in the biological reaction tank to discharge the separated water, an aerobic digestion means (an aeration tank 14) which digests a part of the activated sludge separated by the solid-liquid separation means, and digested sludge return passage 24 which returns the digested sludge digestion-treated in the aerobic digestion means to the biological reaction tank. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
