Effects of liquid and particle conditions on a slurry viscosity reduction in a smaller particle admixing system

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K05131
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 27010:Transport phenomena and unit operations-related
• Research Institution: Doshisha University
• Principal Investigator: Yoshida Mikio 同志社大学, 理工学部, 教授 (60444650)
• Project Period (FY): 2021-01-01 – 2023-03-31
• Keywords: スラリー粘度 / 粘度低減効果 / 微小粒子添加条件 / スラリー液体条件 / 粒子構造

Outline of Final Research Achievements

We investigated effects of liquid and particle conditions on a slurry viscosity reduction in a smaller particle admixing system. We used particles with spherical and almost uniform diameter as main and admixed smaller particles for slurries to investigate easily the reduction mechanism in this system. We prepared various slurries by changing the type of liquid, main and admixed particle volume concentration, admixed particle diameter, and measured viscosity of the slurries. As a result, the viscosity reduction was largely obtained at the main particle volume concentration of more than 50%. This result suggested that the viscosity reduction mechanism can be explained by decreasing a frictional force between the main particles because the main particles sandwiched the admixed particles. Furthermore, the reduction increased when the admixed particle diameter was 0.25 times as large as the main particle one, and when a part of the admixed particle formed relatively small agglomerations.

Free Research Field

粉体工学，化学工学

Academic Significance and Societal Importance of the Research Achievements

ほとんどの工業プロセスには「粒子プロセス」が存在するため，「粒子を高度にハンドリングする技術」は極めて重要である。しかし，スラリー(液体の中に固体粒子が全面的に浮遊している固液混合物)を高濃度で扱う場合は一般に粘度が高く，ハンドリングでトラブルが生じる。したがって，高濃度スラリーの粘度を低減する方法の確立が重要となる。スラリーの粘度低減方法の1つに本微小粒子添加方法があり，本研究によりその粘度低下メカニズム解明に繋がる重要な知見が得られたと考えられる。