Configuration Design of Multi-Zone Circulating Reactors Used in Polyolefin Production

A 3-D model based on computational fluid dynamics (CFD) was developed for comparing the hydrodynamics of four different multi-zone circulating reactor (MZCR) designs to determine the importance of effect of geometry on the reactor performance. The system was modeled by the two fluid model (TFM) based on the kinetic theory of granular flow (KTGF). The re-normalization group (RNG) k-ε model was applied for implementing the turbulency. After qualitative evaluating the hydrodynamic behavior, the best design was found to be a return leg with a side flow which results in a good solid circulation and proper solid distribution. This design ensures fast fluidization and pseudo packed bed regimes in riser and downer, respectively.