The performance of an inclined rotating fixed-bed reactor with concentric inner tube is analyzed for the hydrogenation of alpha-methylstyrene. In particular, the influences of low to intermediate rotational velocities (0.6-10 rpm), inclination angle (45 degrees -75 degrees) and superficial gas velocity (0.05-0.15 m s-1) on the space-time yield at stratified flow conditions are investigated, which is the most beneficial operation mode. A performance enhancement of up to 20% compared to the upright stationary trickle-bed reactor is obtained for the operating conditions studied experimentally. Here, operating conditions show highest performance at low inclination angles due to the most favourable mass transfer conditions. Additionally, a hybrid model approach comprising a 3D Eulerian-Eulerian model and a 1D heterogeneous continuum model is proposed to predict the space-time yield of the rotating reactor. Simulations show the capability of the model to properly predict the effect of operating conditions and reactor dimensions.

The inclined rotating fixed-bed reactor with inner tube is a promising process intensification concept for gas-limited reactions. In order to take full advantage of the reactor concept the installation of an inner concentric displacement tube is proposed to support the wetting intermittency of the whole fixed-bed at stratified flow with different liquid filling levels. The liquid phase distribution is characterized with a capacitance-based wire-mesh sensor, which is designed to cope with organic liquid, porous catalyst packings and reactor rotation. The effects of operating conditions and design parameters on flow stratification, liquid filling level and specific pressure drop are analysed to identify the process windows. Superficial liquid velocity and inclination angle were found to significantly influence the liquid filling level, while rotational velocity and superficial gas velocity have minor effects. Besides, reducing the particle diameter is an effective measure to manipulate the stratification patterns and the associated pressure drop.

Wire-mesh sensors are increasingly used for flow imaging in packed beds. In this study, a capacitance wire-mesh sensor is applied to measure the cross-sectional liquid phase distribution in a rotating fixed-bed reactor. The liquid filling level is derived as a crucial parameter defining the operational window of the reactor concept. Contrary to the standard sensor configuration, wireless data transfer and autonomous power supply is integrated. Furthermore, appropriate data processing is required to visualize the liquid flow of the three-phase system (nitrogen, cumene and gamma-Al2O3 particles).

Essay: One of the most relevant performance parameters is the volumetric mass transfer coefficient (k L a).This paper is revealing new insights achieved for large-scale bioreactor characterization on the basis of a new methodology for measuring the k L a coefficient.Furthermore, examples are included, outlining the benefits in practical applications...........

A heterogeneous modeling approach for an inclined rotating fixed bed reactor with concentric internal tube is introduced. The novel reactor is designed to intensify the mass transfer of gas-limited heterogeneous catalyzed reactions by intermittent catalyst wetting, which is enabled exposing the packed bed to rotation and inclination. A simulation study for the hydrogenation of alpha-methylstyrene is presented. In particular, the influence of period length and different wetting-draining cycles on the space-time yield of the reactor is analyzed.