| 摘要 |
PROBLEM TO BE SOLVED: To provide an organic waste water treatment plant that comprises a centrifugal concentrator or centrifugal dewaterer, and that can reduce immixing of a sludge into return water and suppress phosphorus concentration increase in the effluent water, and to provide a method for operating the same.SOLUTION: A method for operating an organic waste water treatment plant, includes: during start-up of a centrifugal concentrator, start-up discharge water is returned to an excess sludge tank; when comprising also a centrifugal dewaterer, during the start-up of the centrifugal dewaterer, the start-up discharge water is returned to a mixed sludge tank; and after the centrifugal concentrator or centrifugal dewaterer has reached a steady state, the separated water from the centrifugal concentrator or centrifugal separator is returned to the upstream side of a biological treatment tank. By returning the start-up discharge water from the centrifugal concentrator or centrifugal dewaterer at the start-up to the excess sludge tank or mixed sludge tank, said excess sludge having immixed the start-up discharge water can efficiently be immobilized as a dewatered cake during a steady state operation and increase of phosphorus concentration in the effluent water can be prevented. |
