International R&D of innovative measurement and purification technology that accelerate the development of fine bubble science

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H02508
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 27010:Transport phenomena and unit operations-related
• Research Institution: Keio University
• Principal Investigator: Terasaka Koichi 慶應義塾大学, 理工学部(矢上), 教授 (00245606)
• Co-Investigator(Kenkyū-buntansha): 藤岡 沙都子 慶應義塾大学, 理工学部(矢上), 准教授 (50571361)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ファインバブル / ウルトラファインバブル / 気泡 / 気液分離

Outline of Final Research Achievements

It is extremely difficult to separate ultrafine bubbles (UFB) from the wataer coexisting UFBs and solid nanoparticles, making it difficult to accurately evaluate the unique properties of UFB. Therefore, in this study, we developed a new technology that can distinguish between bubbles and solid particles in water, derived from the laser scattering nanoparticle analysis method, and developed and evaluated a super clean UFB water generation method. We also invented an advanced separation method for UFBs in water by slow forward freezing. Furthermore, we succeeded in concentration method of UFB by low-pressure aqueous phase evaporation. Next, we realized the UFB generation technology from the water phase bulk using poor solvent bubble generation.

Free Research Field

化学工学、ファインバブルサイエンス

Academic Significance and Societal Importance of the Research Achievements

現在非常に注目され普及が進んでいるUFBは、水中でキャビテーション、圧壊、ラジカル発生など特異的な機能を持っている。しかしながらUFBの生成メカニズムと安定メカニズムは未だ不明である。本研究では外界と完全に隔離した系で生成した超純水中のUFBを分析し、UFBの発生および安定化メカニズムの仮説を提案した。この成果は今後ますます社会的普及と新規開発が行われるUFB技術の発展に大きく寄与すると予想される。