The status of polyethylene (PE) particle size and distribution

bubble generation and movement

and polymerization reaction in gas phase ethylene polymerization fluidized-bed reactor (FBR) is significant for PE production process

reactor design

optimization and control. Based on 3 dimensional (3D) Eulerian-Eulerian two-fluid model combined with a population balance model (PBM)

this work aims to explore the two-phase flow characteristics and the effects of traditional PE production process (Geldart B particles) and non-pelletizing PE production process (Geldart D particles) on the operating behaviors in a pilot-plant FBR. The simulation results match well with the industrial measured pressure drop and temperature data. It is also found that the polymer particles observably concentrated on the bed inlet region for the effects of Geldart D particles and superfical gas velocity. In addition

the obvious vortexes and large bubbles can be clearly observed in the bed height direction. The results could provide foundation for the extension and application of the non-pelletizing PE production process.