マイクロバブルによる富栄養貯水池の深層水の水質改善に関する現地試験

Field experiment on hypolimnic aeration using micro oxygen bubbles in a eutrophic reservoir

Kawahara Yoshihisa

Takeuchi Yutaka

Nonomura Atsuko

Matsuo Katsumi

水工学論文集

An in-situ experiment on hypolimnic aeration was carried out in Fuchu reservoir, which has been suffering from severe eutrophication, from mid-August to early December in 2004. Micro oxygen bubbles were injected into the anaerobic hypolimnion to improve water quality without disturbing the thermal stratification. Before the destratification due to big typhoons in the late September, some fundamental information was obtained which is useful in designing and maintaining an aeration system applied to eutrophic reservoirs. The operation of the micro-bubble aeration system increased the dissolved oxygen concentration to 1～3mg/L together with the decrease in electric conductivity, but within a limited area. This was explained by the very high consumption rate of dissolved oxygen in hypolimnic water and by bed materials. And the necessity was recognized to prevent the aerator nozzles from clogging accompanied by the oxidation of dissolved iron.

micro-bubble aeration

eutrophication

hypolimnion

dissolved oxygen

thermal stratification

field experiment

Construction. Civil engineering [ 510 ]

jpn

土木学会

[ISSN] 0916-7374

[NCID] AN10426673