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Journal of Central South University

, Volume 18, Issue 5, pp 1383–1388 | Cite as

Characteristics of non-magnetic nanoparticles in magnetically fluidized bed by adding coarse magnets

  • Li Zhou (周立)
  • Run-li Diao (刁润丽)
  • Tao Zhou (周涛)Email author
  • Hiroyuki Kage
  • Yoshihide Mawatari
Article

Abstract

The fluidization behavior of SiO2, ZnO and TiO2 non-magnetic nanoparticles was investigated in a magnetically fluidized bed (MFB) by adding coarse magnets. The effects of both the amount of coarse magnets and the magnetic field intensity on the fluidization quality of these nanoparticles were investigated. The results show that the coarse magnets added to the bed lead to a reduction in the size of the aggregates formed naturally by the primary nanoparticles. As the macroscopic performances of improved fluidization quality, the bed expansion ratio increases whilst the minimum fluidization velocity decreases with increasing the magnetic field intensity, but for TiO2 nanoparticles there exists a suitable magnetic field intensity of 0.059 6 T. The optimal amounts of coarse magnets for SiO2, ZnO and TiO2 non-magnetic nanoparticles are 40%, 50% and 60% (mass fraction), respectively. The bed expansion results analyzed by the Richardson-Zaki scaling law show that the exponents depend on both the amount of coarse magnets and the magnetic field intensity.

Key words

non-magnetic nanoparticles magnetic fluidization agglomerate coarse magnet 

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Copyright information

© Central South University Press and Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Li Zhou (周立)
    • 1
    • 2
  • Run-li Diao (刁润丽)
    • 1
  • Tao Zhou (周涛)
    • 1
    Email author
  • Hiroyuki Kage
    • 3
  • Yoshihide Mawatari
    • 3
  1. 1.School of Chemistry and Chemical EngineeringCentral South UniversityChangshaChina
  2. 2.Department of Mechanical EngineeringHunan Institute of TechnologyHengyangChina
  3. 3.Department of Applied ChemistryKyushu Institute of TechnologyTobata, KitakyushuJapan

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