Computational Fluid Dynamics Modeling of Temperature Distribution in Fluidized Bed Polymerization Reactor for Polypropylene Production

Abstract

Propylene polymerization process is one of the chemical processes that take place in the fluidized bed reactor. The gas monomer is fed through the distributor to react with the solid catalyst particles inside the reactor. The polymer particles are produced from the heterogeneous exothermic polymerization reaction. Although the fluidized bed polymerization reactor has high heat and mass transfer rate, the thermal efficiency is usually limited due to the formation of hot spots and improper mixing. In this research, a computational fluid dynamics (CFD) model of the fluidized bed polymerization reactor for polypropylene production is developed in order to study the temperature distribution within the reactor. The polymer growth rate and particle size distribution are included in the CFD model development. The heat is generated from highly exothermic polymerization reaction and removed in the heat exchanger. By proper adjusting the monomer feed velocity, the uniform temperature distribution inside the reactor is obtained in axial and radial directions. Additionally, the temperature of the outlet gas stream can be reduced, thus reducing the external cooling duty.