Laleh Rezaeian - Chemical Engineering Department, Faculty of Engineering, Ferdowsi University ofMashhad,Mashhad, Iran
Nasser Seghatoleslami - Petroleum Department, Faculty of Engineering, Iqbal Lahori University, Mashhad, Iran

Gas-solid fluidized beds have been considered by many researchers due to their high importance in the industry. Many efforts, both experimentally and theoretically, have been made to predict their behavior. Particle Segregation due to differences in particle size is a common phenomenon in gas-solid fluidized beds. Particle segregation affects efficiency of heat transfer and mass transfer in the fluidized bed. When there are both small and large sized particles with the same density in a fluidized bed, larger particles aggregate at the bottom and smaller particles at the top of the bed. In fluidized bed reactors in which exothermic reaction occurs, to eliminate hot-spots and prevent degradation of products, creating proper mixing in the bed is required. On the other hand, the segregation phenomenon is required for processes involving particle segregation.To improve the efficiency of these processes, it is necessary to understand specifications of segregation and mixing in these systems with further details. On the other hand, most gas-solid fluidized beds work at high pressure. It is therefore imperative that mixing and segregation phenomena at high pressures be predicted for these beds. To this end, MFIX software is used to measure pressure effect, particle size and gas inlet velocity on mixing and segregation parameters in these beds. Paraview is also used to analyze data from MFIX. The results show that computational fluid dynamics can be used as a research tool to estimate the parameters affecting performance of fluidized beds

Gas-solid fluidized beds, particle segregation, CFD, MFIX, Paraview