| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a sewage and sludge treatment method capable of reducing the vol. of sludge in a biological denitrifying and dephosphorizing sewage treatment flow and capable of performing the removal of org. matter and high-degree denitrifying and dephosphorizing treatment only by withdrawing the min. amt. of sludge as excessive sludge. SOLUTION: In a sewage and sludge treatment method for biologically denitrifying and dephosphorizing sewage A introduced into a batchwise reaction tank 2 by batchwise operation, a part of sludge sedimented in the batchwise reaction tank 2 is introduced into a sludge treatment tank 4 to perform the concn. of sludge and the discharge of phosphorus from sludge and this treated sludge is guided to a flocculation and sedimentation tank 5 while a flocculant D is added to the supernatant thereof to be sedimented and separated as flocculated sludge C and the cone. sludge is guided to a sludge solubilizing tank 6 to be subjected to solubilizing treatment before returned to the batchwise reaction tank 2.</p> |
