| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve the water quality of a river with small energy consumption. <P>SOLUTION: A plurality of oxygen supply devices 5 are arranged at intervals from an upstream side to a downstream side of a tidal river. A duct 10 of each oxygen supply device 5 is laid on a river bed 1 to extend in a river width direction, and while an air introduction end 10a of the duct 10 is arranged on the side of one bank 2 of the river, an air discharge end 10b is arranged on the side of the other bank. The space in the duct 10 serves as a blast path, a blast fan 25 (gas transfer means) is connected to the air introduction end 10a or air discharge end 10b of the duct 10, and the air is introduced from the air introduction end 10a, made to pass through the blast path, and discharged from the air discharge end 10b. The duct 10 is provided as a gas permeation part which has enough rigidity to maintain circulation cross sectional area of the blast path, and at least has an upper part that water does not permeate and gas permeate. <P>COPYRIGHT: (C)2013,JPO&INPIT |
