METHOD FOR CONTROLLING TREATMENT OF SEWAGE BY OXIDATION DITCH PROCESS

摘要

PURPOSE:To carry out aeration fit for low load of pollution and to prevent the sedimentation and deposition of sludge by rotating an aerating rotor at a low speed and moving a movable weir upward so that the depth of the rotor immersed in sewage is increased only in a time zone with low load of pollution. CONSTITUTION:A movable weir 7 for allowing treated water to overflow is set in the circulating path 2 of a ditch tank 1 in which sewage is aerated and fluidized with an aerating rotor 3. Only in a time zone (e.g. the night) with low load of pollution, the rotor 3 is rotated at a lower speed than a rated speed and the weir 7 is moved upward so that the depth of sewage in the tank 1 is increased. After the lapse of the specified time zone, the rotor 3 is rotated at the rated speed and the weir 7 is returned to the original position.