Application and elucidation of mechanisms of ozone ultra-fine bubbles for waste sludge reduction

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K04748
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22060:Environmental systems for civil engineering-related
• Research Institution: Fukuoka University (2022-2023); Hiroshima University (2020-2021)
• Principal Investigator: Hashimoto Kurumi 福岡大学, 工学部, 助教 (40821012)
• Co-Investigator(Kenkyū-buntansha): 西嶋 渉 広島大学, 環境安全センター, 教授 (20243602)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: ウルトラファインバブル / 微細気泡 / 余剰汚泥 / 減容化 / オゾン

Outline of Final Research Achievements

The effect of bubble sizes on the penetration of UFBs into sludge was examined, and it was found that UFBs of 10-20 nm in diameter can penetrate into the sludge. In contrast, microbubbles cannot penetrate into the sludge. It was also found that agitation by the UFB generator disintegrates the sludge surface and increases its reactivity with ozone UFBs. However, that agitation does not cause penetration of ozone UFBs into the hard and compacted central part of the floc. The effect of the surface charge of the sludge and UFB was not observed.

Free Research Field

環境工学

Academic Significance and Societal Importance of the Research Achievements

UFBの応用を発展させていくためには、基礎的なオゾンUFBの作用機序の解明が非常に重要である。UFBは洗浄や生理活性効果などが多数報告されているが、目に見えないため、作用機構の詳細は不明確である。オゾンUFBの汚泥への作用機構を明らかにすることは、余剰汚泥の処理だけではなく、UFBを利用する他分野にも大きな影響を与えると考えられる。