Simulations of Liquid Spreading and Particle Aggregation in Gas-Fluidized Beds

• Author / Creator

  Wasylkiewicz, Monika J

• Introduction of a binding or reacting liquid into a gas-solid fluidized bed is
  common in industrial processes (e.g. fluid coking, catalytic cracking, granulation).
  Ability of the liquid to spread and the attractive effect on particles due to liquid
  bridge formation alter the fluidization behavior and process efficiency.
  Direct numerical simulations are performed using the lattice-Boltzmann method, with liquid modeled as a scalar transferred during particle collisions. A liquid spreading model is introduced based on a liquid bridge growth rate, and liquid
  spreading is studied and analyzed in terms of diffusion coefficients. Then, a system
  of homogeneously wetted particles is simulated, with an attractive force applied between adjacent particles. Aggregate sizes and fluidization behavior are examined. Liquid diffusion is slower horizontally than vertically. The relation between liquid spreading and solids volume fraction depends on liquid viscosity and surface tension. Systems simulated generally completely aggregate, with aggregation resulting in slip velocity increases.

• Subjects / Keywords

  • Lattice-Boltzmann method
  • Gas fluidization
  • Aggregation
  • Wet particles
  • Liquid spreading

• Graduation date

  Spring 2014

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R38911X86

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.