NITRIFICATION CARRIER CIRCULATION METHOD OF DEEP AERATION TANK

PROBLEM TO BE SOLVED: To provide a nitrification carrier circulation method allowing the nitrification carrier added to a deep aeration tank treating organic wastewater like sewage containing nitrogen compounds to circulate through the whole tank without accumulating at tank corners. SOLUTION: Air diffusers 3 are disposed near an intermediate stage of one side of a baffle plate 2 vertically set at a center of the tank, along the flow down direction of treating water. A vertical partition plate 4 with an upper end set from 0.5m above the air diffusers to an upper end of the baffle plate, and a lower end set 0.5-2m above a tank bottom, is provided parallel to the tank wall at a position 0.2-2m from the tank wall parallel to the baffle plate and including a part of the air diffusers 3. This configuration causes a straightened upflow between the partition plate 4 and tank wall, and circulation of the nitrification carrier added to the tank on the upflow. COPYRIGHT: (C)2009,JPO&INPIT