Airlift aeration tank suitable for batch activated sludge process

摘要

PPROBLEM TO BE SOLVED: To provide an air lift aeration tank suitable for a batch activated sludge process which can sufficiently cope with wastewater having a high nitrogen load, namely high nitrogen content wastewater, for example, wastewater of a food plant, by enabling the control of a liquid circulation quantity in an aeration tank without being influenced by the water level of treated liquid in the aeration tank even if the water level fluctuates. PSOLUTION: This air lift aeration tank comprises (1) two partition plates for partitioning the inside of the aeration tank, consisting of (i) a first partition plate for vertically partitioning the tank up to a fixed height so as to leave a fixed space between it and the bottom of the aeration tank, and (ii) a second partition plate for vertically partitioning the tank up to a fixed height so as to leave a fixed space above the first partition plate, (2) an air blowing means installed on the bottom or in the vicinity of the bottom of one side of the aeration tank partitioned by the partition plates, (3) a wastewater introduction means installed in the other side of the aeration tank partitioned by the partition plates, and (4) an aeration tank having an inclined plane, preventing sludge in the tank from depositing, in the vicinity of the bottom of the aeration tank to which the wastewater introduction means is attached. PCOPYRIGHT: (C)2005,JPO&NCIPI