CFD modeling of gas–liquid mass transfer process in a rotating packed bed

Abstract

Process intensification by rotating packed bed (RPB) has attracted wide attention in the recent years. In particular, its high gas–liquid mass transfer efficiency is proved by plentiful experimental data. However, due to the complex structure of packing in the RPB, it is extremely difficult to acquire detailed information about mass transfer process inside the reactor by experiments. Therefore, this study firstly employed computational fluid dynamics (CFD) modeling technique to analyze mass transfer process in a rotating packed bed (RPB) by adding user defined function (UDF) programming to Fluent solver in order to expand its abilities to RPB. The simulation results were compared with previous correlation data on liquid holdup and the calculated values of mass transfer process were matched with experimental values of vacuum deaeration process in RPB. The results revealed liquid flow and mass transfer process inside the reactor and were also in agreement with the experimental data. Additionally, three optimum designs of RPB (kinds of packing, size of rotors and blades added in packing) were developed to improve the mass transfer efficiency. The results show high removal efficiency in the small Δd packing and the rotor with larger inner and outer diameter, and the packing with blades can improve mass transfer efficiency compared to the conventional one. The CFD technique was generally found to be an important and effective tool for analyzing and optimizing RPBs.