METHOD FOR PREVENTING ACCUMULATION OF POLLUTED SAND IN OXIDATION DITCH

摘要

PURPOSE:To provide a method for preventing polluted sand from being accumulated in the aeration tank of an oxidation ditch method and from being anaerobically putrefied. CONSTITUTION:A piece of a mechanical type aerating machine 3 or a plurality of sets thereof are provided in the position of water surface of the aeration tank 1 of an oxidation ditch method by which organic drainage is biologically treated by activated sludge. Furthermore an underwater type agitator 4 is provided in the bottom of a water tank at the upstream side of these aerating machines 3. A time zone for operating the mechanical type aerating machine 3 at maximum speed or for operating the whole set thereof at least once daily is set up. The agitator 4 is operated while being set by the time zone. Thereby polluted sand is prevented from being accumulated.