As a novel multiphase contactor, Rotating Packed Bed (RPB) can greatly intensify the processes of micromixing and mass transfer. Recently, RPB has been successfully applied to manufacturing nanomaterials by reactive precipitation and for separation in process industry. There have been a number of experimental studies concerning the phenomena of fluid flow and mass transfer within RPB, most of which ended up in obtaining empirical correlations. In this paper, the gas flow and the dispersed liquid flow in RPB are simulated using a Eulerian-Lagrangian approach. Based on the appropriate simplifications on the dispersed liquid flow and the construction of the net packing, the gas flow and the trajectory of the liquid droplets in RPB are obtained by SIMPLE algorithm and particle trajectory model respectively with coalescence and breakage of the liquid droplets being considered. Upon the numerical results of the gas phase and the dispersed liquid flow, the mass transfer coefficient of the liquid phase is calculated. The model results are in fair agreement with the experimental data of desorption of O_2 dissolved in water by N_2 giving an averaged relative error of 7.6%, which verifies the methodology and the applicability of present model in predicting the fluid flow and the mass transfer in RPB. Present numerical simulation illustrates the development of gas velocity mainly depends on geometric structure of RPB and rotating speed of packing, which is especially different from the conventional packed beds. It is depicted that the droplets in the voids of the rotating packing flow outward in different directions, which deviate from the incident direction. Further, the influences of some operation parameters such as the rotating speed, the flow rates of the liquid phase and the gas phase as well as the inner diameter of the packing on the mass transfer coefficient are also discussed. It is found that the coefficient of mass transfer increases greatly as the flow rate of liquid and the inner diameter of packing rises. According to the model, the intensification on the mass transfer is primarily contributed to the liquid atomization by the rotating packing.
展开▼
