New development of nanofiber air filter beyond single fiber theory

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K18846
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 27:Chemical engineering and related fields
• Research Institution: Kanazawa University
• Principal Investigator: Seto Takafumi 金沢大学, フロンティア工学系, 教授 (40344155)
• Project Period (FY): 2021-07-09 – 2023-03-31
• Keywords: エアフィルタ / エアロゾル / ナノファイバ / 集塵

Outline of Final Research Achievements

In air filters using nanofibers, a comparison of the experimentally measured filtration efficiencies for different particle types and the estimated values based on the single fiber collection theory showed that the collection efficiency was reduced for coarse particles due to a decrease in adhesion force. By observing the collection state with a scanning electron microscope, it was confirmed that collection by multiple fibers is predominant for fibers with a fiber diameter relatively smaller than the particle diameter. It was also found that particles form aggregates on the fiber surface at the position of stable collection. These results clarify the particle collection mechanism on the surface of nanofibers beyond the limits of conventional theory, and are significant because they provide design guidelines for air filters used in industrial applications.

Free Research Field

化学工学

Academic Significance and Societal Importance of the Research Achievements

新型コロナウイルス感染症の出現により、その感染予防手段としてマスクや空気浄化装置等に使用されるエアフィルタへの需要が世界的に急増し、その性能向上が急務となっている。単一繊維捕集（SFC）理論によれば、繊維が微細化すると、さえぎりによる捕集効率が向上するとともに、流体の滑り効果による圧力損失の低減により、フィルタ性能の大幅な向上が予測される。本研究で得られた成果は、「SFC理論の限界」を明らかにして、新たなエアフィルタ理論を構築するものであり、ナノ領域における新たなエアフィルタの設計指針を与えるものである。