OPERATION CONTROLLING METHOD OF WATER TREATING DEVICE BY INTERMITTENT AERATION TYPE ACTIVATED SLUDGE METHOD AND DEVICE THEREFOR

摘要

PURPOSE:To improve the removal of an sludge component in sewage by sequencing previously plural aeration operation patterns in decreasing order of an aeration effect and changing the pattern based on the order of the aeration effect corresponding to a variation in the quality of water to be treated. CONSTITUTION:The pattern in which an aeration treating time and an aeration stopping time per one time is made constant during an intermittent aeration treating stage is sequenced in large order of repeating times of the aeration and the aeration stopping. Then, the difference between a nitrate nitrogen concn. and an ammoniacal nitrogen concn. in the water to be treated is calculated by an arithmetic processor 9, and, this difference and a previously set target value are compared by a comparison arithmetic processor 10. By the comparison arithmetic processor 10, when the difference between the nitrate nitrogen concn. and the ammoniacal nitrogen concn. in the water to be treated is smaller than the target value, it is judged that the presently operating pattern must be transferred to a pattern higher in the aeration effect. On the other hand, when the calculated value is larger than the target value, it is judged that the presently operating pattern must be transferred to a pattern lower in the aeration effect.