A three-compartment model was used to study turbulent flow field in a baffled stirred tank. Three different zones of the vessel, that were impeller zone, baffle zone and circulation zone were investigated. Boundaries of these zones were determined using a new method, namely gradient method and a traditional cumulative energy dissipation method. Zone boundaries determined by both methods were comparable. Effect of some parameters on turbulent flow field was also studied. Both turbulent kinetic energy (TKE) and TKE dissipation rate showed a considerable variation with agitation rate in all three zones and with impeller diameter only in impeller zone. Three-compartment model was also used to predict Particle size distribution (PSD) of poly (vinyl chloride) in an industrial suspension polymerization reactor using Population balance model. CFD simulations were performed to obtain turbulence parameters for solving population balance model. Adjustable parameters of population balance model were calculated using experimental PSD data for grade65. The population balance was also used to predict PSD of grade70 that was in good agreement with experimental data. Sauter mean diameter of the produced PVC powder increased with dispersed phase volume fraction and decreased with suspending agent concentration. It was also found that sauter mean diameter variation with agitation rate passed a minimum.
