Rotating packed beds (RPBs) aim to intensify mass transfer processes by exploiting centrifugal forces. The limited use of RPBs in the chemical industry can be explained among others by missing comparative studies between state of the art equipment (e.g., packed columns) and RPBs to quantify the benefits that come along by the use of RPBs. The effective interfacial area, mainly dependent on the rotational speed, was found to be equal for both rotors (outer packing radii of 0.18 and 0.28 m, respectively) for rotational speeds larger than 20 s–1. The specific energy dissipation per provided interfacial area is newly introduced in order to link the pressure drop with the mass transfer. Compared to packed columns, the moles of CO2 absorbed per packing volume were found to increase by a factor of up to 3 in RPBs.

Rotating packed beds (RPBs) overcome gravitational limitations by the utilization of centrifugal fields. The cocurrent deaeration of water with nitrogen is studied for centrifugal accelerations of up to 224-times gravitational acceleration. The performance increase of packed rotors with different packing materials (knitted mesh, metal foam) compared to an empty rotor is evaluated. The comparison of mass transfer experiments conducted in a lab-scale and a pilot-scale RPB enables the derivation of scale-up guidelines. For an increased radial packing length of 0.152 m, the industrially relevant oxygen outlet concentration of less than 50 ppb is reached at a 50% lower rotational speed. Furthermore, the results indicate the importance of nonconstant k L a values for scale-up computations.

Cryogenic liquid propellants are used in liquid rocket engines to obtain high specific impulse. The flow rates are controlled by turbopumps that deliver liquid propellant to the engine at high pressure levels. Due to the very low saturation temperature of the cryogenic propellant, in the first phases of the transient operation, in which the engine is at ambient temperature, its surfaces are subject to boiling conditions. The effect of boiling on the heat transfer between the solid and the fluid needs to be well characterized in order to correctly predict the cryopump metal temperature temporal evolution and the necessary amount of propellant. With the aim of benchmarking numerical tools against experimental data, a representative test case was chosen. This consists of a stator-rotor-stator spinning disc reactor studied under single-phase and two-phase heat transfer conditions. The numerical approaches used are represented by a 1D network solver, where the pressure drop and heat transfer are calculated by correlations, and Computational Fluid Dynamics (CFD) simulations, carried out with ANSYS Fluent. Both the numerical tools returned a reasonable agreement in single-phase conditions, also thanks to the use of adequate correlations in the flow network solver and typical conditions for the CFD simulations. Two-phase conditions on the contrary are more challenging, with underpredictions up to 20 % and 80 %, respectively. The issues are ascribable to the use of correlations that are inadequate to capture the two-phase phenomena occurring in the srs reactor and numerical limitations in the actual implementation of the boiling model in the CFD solver.