| 摘要 |
<p>PURPOSE: To carry out the aeration efficiently in a deep aeration tank by creating a circulating stream of water entirely in a tank by synergistic effects of an air lift action of bubbles due to aeration and an agitating downward stream caused by a screw of an aeration machine. CONSTITUTION: There are provided a draft tube 3 which is provided below a screw type aeration machine 2 provided in an aeration tank 1 so as to be opposed to the machine 2 to lead a stream caused by the thrust of a screw 22 and bubbles for aeration to the bottom of the tank, a bubble recovery buffer 5 which is disposed around the outer periphery of an opening of the lower end of the tube 3 to recover large bubbles, and bubble guiding pipes 6 which are radially arranged on the buffer 5 to lead the recovered bubbles from the buffer 5 toward the inner circumferential wall surface in the tank 1 thereby discharge the bubbles into the tank.</p> |
