To provide an air lift pump device capable of reducing power required to transfer water to be treated from one of treatment tanks connected across a partition wall to the other treatment tank and efficiently supplying the water.
An air lift pump device 40 comprises: a lifting pipe 41 arranged in a second area; a diffuser device 42 including a diffuser part 42a arranged under a bottom opening 41a of the lifting pipe 41, for discharging bubbles to the bottom opening from the diffuser part; and a water pipe 43 arranged in a substantially horizontal posture for transferring water to be treated, which is lifted by the bubbles, from an upper portion of the lifting pipe 41 to an oxygen-free tank adjacent to the second area across a partition wall. The water pipe 43 includes an enlarged part 43a in which cross-sectional area becomes larger toward a downstream side. In the enlarged part 43a, an inside upper face of the water pipe is formed so as to incline upward toward the downstream side.
AKIYOSHI HIDEKI
YATSUGI SOICHIRO
| JPH0957262A | 1997-03-04 | |||
| JPH03262600A | 1991-11-22 | |||
| JPS61218800A | 1986-09-29 |