TREATMENT METHOD FOR ANAEROBIC/AEROBIC ACTIVATED SLUDGE AND APPARATUS THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide an anaerobic/aerobic activated sludge treatment method capable of removing nitrogen and phosphorus in water to be treated stably.;SOLUTION: In the anaerobic/aerobic activated sludge treatment method for performing the treatment of organic wastewater in an intermittent aeration tank 4 by biological treatment repeating a cycle comprising an aeration process and a non-aeration process, a predetermined ratio of an aerobic time and an oxygen-free time in the intermittent aeration tank 4 is set to a target ratio α₀ and the time Kx required until the concentration of dissolved oxygen DO becomes a predetermined value or less after the completion of the aeration process is calculated by measuring the DO in the intermittent aeration tank 4 before the front cycle. On the basis of this time Kx, the time of the aeration process and the time of the non-aeration process are controlled so that the ratio of the aerobic time and the oxygen-free time of the cycle of this time becomes the target ratio α₀.;COPYRIGHT: (C)2004,JPO