Development of cyanobacteria control device that applies low-frequency vibration of underwater speaker

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K12292
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 64020:Environmental load reduction and remediation-related
• Research Institution: Shinshu University
• Principal Investigator: Park Hodong 信州大学, 学術研究院理学系, 教授 (20262686)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: アオコ制御装置 / アオコ発生の抑制技術

Outline of Final Research Achievements

We developed a device that generates low-frequency vibrations by applying an underwater speaker. A prototype low-frequency oscillator was connected to the underwater speaker to complete the cyanobacteria bloom control device. We then used the completed device to conduct multiple cyanobacteria bloom control experiments to confirm the performance of the low-frequency oscillator and determine the optimal control frequency. The results of this year's experiments confirmed that a better control effect could be obtained than in previous cyanobacteria bloom control experiments with an underwater speaker and low-frequency oscillator at 20 Hz or less frequencies. We conducted a scaled-up vibration wave generation experiment using a newly purchased large speaker and power amplifier. We completed a prototype cyanobacteria bloom control device that uses cyanobacteria bloom. We plan to use this device in outdoor demonstration experiments in the future.

Free Research Field

環境毒性学

Academic Significance and Societal Importance of the Research Achievements

本研究で開発されたアオコ制御装置は、アオコの細胞膜を破壊せずにガス胞のみを壊すことで、アオコの浮上能力を抑制することが本装置の特徴的な強みである。アオコの毒素は細胞内に存在しており、アオコ制御剤やアオコの細胞を破壊するような装置の場合はアオコの制御の際に毒素が流出し他の生物に影響を与えることや浄水過程で飲料水を汚染することが報告されている。しかし、本研究で開発された水中スピーカーを応用した低周波振動装置は、アオコの細胞を破壊せずにガス胞のみを破裂させてアオコが集積している湖沼の表層から深層に沈殿させることでアオコの発生を事前に抑えることができる優れたアオコ発生防止装置として活用できる。