Numerical simulation of liquid–solid two-phase flow in a tubular loop polymerization reactor

Understanding hydrodynamics of tubular loop reactors is crucial in proper scale-up and design of these reactors. Computational fluid dynamics (CFD) models have shown promise in gaining this understanding. In this paper, a three-dimensional (3D) CFD model, using a Eulerian–Eulerian two-fluid model incorporating the kinetic theory of granular flow, was developed to describe the steady-state liquid–solid two-phase flow in a tubular loop propylene polymerization reactor composing of loop and axial flow pump. Corresponding simulations were carried out in the commercial CFD code Fluent. The entire flow field in the loop reactor was calculated by the model. The predicted pressure gradient data were found to agree well with the classical calculated data. Furthermore, the model was used to investigate the influences of the circulation flow velocity and the sold particle size on the solid hold-up. The simulation results showed that the solid hold-up has a relatively uniform distribution in the loop reactor at small particles in volume and high-circulation flow velocities.