Conceptual Design of Microplastic Collection Device from Seawater with Magneto-Archimedes Effect

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K20989
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 21:Electrical and electronic engineering and related fields
• Research Institution: Hokkaido University
• Principal Investigator: Noguchi So 北海道大学, 情報科学研究院, 准教授 (30314735)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: Ultrahigh magnetic field / Superconducting magnet / Microplastic collection

Outline of Final Research Achievements

Based on the magneto-Archimedes theory, a new microplastic collector which utilizes a strong magnetic force by a high magnetic field gradient was conceptually designed. Therefore, a simulation tool has been developed to obtain the phenomenon of microplastics in seawater. As a result, it was clarified to need a high magnetic field gradient (12.5 T/m) and a strong magnetic field beyond 10 T over 1.5-m length. Next, a high field magnet was designed satisfying such field conditions. The present magnet-manufacturing technique is inadequate to withstand a high magnetic stress working to the designed magnet. In the future, a new magnet technology to overcome a high stress must be developed.

Free Research Field

High magnetic field application

Academic Significance and Societal Importance of the Research Achievements

海中のマイクロプラスチックの個数は年々増加しており、生態系への影響が懸念されている。東アジア海域のマイクロプラスチック個数は、他の海域に比べて特に多く、マイクロプラスチックの回収装置の開発が強く望まれている。近年、２０テスラを超えるマグネットが開発されてきており、同技術を用いて、マイクロプラスチックを回収する装置の実現可能性について検討した。その結果、電磁応力に耐えうるマグネットを開発できれば、９０％近いマイクロプラスチックが回収可能であることが示された。