2018 Fiscal Year Final Research Report
Development of nitrogen and phosohorus removal technique applying the hypolimnetic oxygenator in a reservoir
Project/Area Number |
17H06874
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Research Category |
Grant-in-Aid for Research Activity Start-up
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Allocation Type | Single-year Grants |
Research Field |
Environmental engineering and reduction of environmental burden
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Research Institution | Shimane University |
Principal Investigator |
Masuki Shingo 島根大学, 学術研究院環境システム科学系, 特任助教 (80806894)
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Research Collaborator |
SEIKE Yasushi
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Project Period (FY) |
2017-08-25 – 2019-03-31
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Keywords | 富栄養化 / 深層曝気 / 硝化 / 脱窒 / ダム |
Outline of Final Research Achievements |
In this research, development of a new technique to reduce water quality problems (like as eutrophication) in the dam lake was attempted.As a result, new techniques for improving eutrophication were developed, and drastic solution methods for various problems (blue algae, mold odor, etc.) caused by eutrophication were shown. The dissolved oxygen concentration(DO) was adjusted to a target concentration in the deep part of the dam lake from 2018 to 2019, and the nitrification (under aerobic condition) and the denitrification (under anaerobic condition) appeared repeatedly.As a result, dissolved inorganic nitrogen(DIN) was reduced (a decrease rate of 100 μg / L / y in 2018-2019). At this time, phosphate(PO4) did not re-elute from the bottom sediment.It is expected that this technique will be widely disseminated to the world as a new eutrophication countermeasure technology.
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Free Research Field |
生態環境工学
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Academic Significance and Societal Importance of the Research Achievements |
本研究では,ダム湖の富栄養化やそれに起因する諸問題を解決するため,水中の栄養塩低減技術の開発を行った。実在のダムに既設された深層曝気装置を使用し,深層水の溶存酸素濃度を任意の値(溶存酸素が高い状態と低い状態)に調整した。溶存酸素濃度を任意の値に調整することで水中の有用微生物(硝化細菌や脱窒細菌)を交互に活性化させ,明確な栄養塩の低減を効果を得た。本原理は下水処理場において用いられる嫌気・硝化内生脱窒法(AOAO法)であり,本研究ではこの原理を実用レベルでダム湖の貯留段階に適用した世界初の試みである。得られた知見は,水資源の有効活用にも大きく貢献できるものと考える。
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