摘要 |
The device of the present invention comprises a rotary shaft to be disposed in a liquid approximately vertically and rotatable about its axis, the rotary shaft having a gas channel axially extending therethrough, and a bubble releasing-diffusing rotor fixedly attached to the lower end of the rotary shaft and having a plurality of liquid agitating projections formed along its periphery at a specified spacing circumferentially thereof, the rotor being formed in its bottom face with a plurality of grooves extending radially from the central portion of the bottom face to the outer end of the respective liquid agitating projections for centrifugally guiding the liquid when the rotary shaft is in rotation. The rotor has gas discharge ports communicating with the gas channel of the rotary shaft via a communication passage and equal in number to the number of the grooves for discharging the gas therefrom so that bubbles are entrained in the liquid centrifugally flowing out from the outer ends of the grooves in the peripheral surface of the rotor. |