Development of a CFD model for the simulation of a novel multiphase counter-current loop reactor

Abstract

Many bio-based processes exhibit low yields resulting from inhibitions. This innovative concept for a multiphase-loop reactor can overcome these limitations with a simultaneous aeration and extraction of valuable compounds in one unit operation.One dispersed phase is used to initiate a loop flow in the reactor while the other phase is dispersed in the downcomer. Therefore, the second dispersed phase rises in the counter-current.The multiphase flow was simulated using a 2D axis-symmetric Euler-Euler approach in CFD. Besides friction force and gravitation the turbulent dispersion force was considered applying the standard k-ε turbulence model. The simulation of the reactor was validated in pilot-plant experiments. A comparison of the holdup of the dispersed phases and a visual evaluation of the flow field presented very good agreements between the experiments and simulations. Water, Shellsol T and synthetic air were used in the experiments. An improvement of the reactor design was possible based on additional simulation studies.