Print Email Facebook Twitter On the hydrodynamics of membrane assisted fluidized bed reactors using X-ray analysis Title On the hydrodynamics of membrane assisted fluidized bed reactors using X-ray analysis Author Helmi, A. (Eindhoven University of Technology) Wagner, E.C. (TU Delft ChemE/Afdelingsbureau) Gallucci, F. (Eindhoven University of Technology) Van Sint Annaland, Martin (Eindhoven University of Technology) van Ommen, J.R. (TU Delft ChemE/Product and Process Engineering) Mudde, R.F. (TU Delft ChemE/Transport Phenomena) Date 2017-12-01 Abstract The application of membrane assisted fluidized bed reactors for distributed energy production has generated considerable research interest during the past few years. It is widely accepted that, due to better heat and mass transfer characteristics inside fluidized bed reactors, the reactor efficiency can outperform other reactor configurations such as packed bed units. Although many experimental studies have been performed to demonstrate and monitor the long term performance of membrane assisted fluidized bed reactors, the hydrodynamics of membrane-assisted fluidized bed reactors has thus far only been studied in pseudo-2D geometries. In this work the solids concentration inside a real 3D fluidized bed reactor geometry was measured using a fast X-ray analysis technique. Experiments were conducted in absence and presence of two different membrane modules with different configurations and number of membranes (porous Al2O3 tubes) for two types of particles, viz. 400–600 μm polystyrene (Geldart B type) and 80–200 μm Al2O3 (Geldart A/B type). Results from the experiments with Geldart B type particles revealed that the membrane modules (both the membranes and the spacers) can significantly reduce bubble growth along the fluidized bed resulting in a smaller average bubble diameter, expected to improve the bubble-to-emulsion mass transfer, whereas for the experiments with fine Geldart A/B particles, and at a very high extraction values (40% of the inlet flow), a densified layer with high solids concentration was formed near the membrane, which may impose an additional mass transfer resistance for gas components to reach the surface of the membranes (concentration polarization). The results from this study help designing and optimizing the positioning of the membranes and membrane spacers for optimal performance of fluidized bed membrane reactors. Subject Fluidized bedSolids concentrationVertical membranesX-ray To reference this document use: http://resolver.tudelft.nl/uuid:0c6f8771-0bf8-4ac5-bef8-103544bc5d17 DOI https://doi.org/10.1016/j.cep.2017.05.006 ISSN 0255-2701 Source Chemical Engineering and Processing: process intensification, 122, 508-522 Part of collection Institutional Repository Document type journal article Rights © 2017 A. Helmi, E.C. Wagner, F. Gallucci, Martin Van Sint Annaland, J.R. van Ommen, R.F. Mudde Files PDF 1_s2.0_S0255270116307280_main.pdf 2.31 MB Close viewer /islandora/object/uuid:0c6f8771-0bf8-4ac5-bef8-103544bc5d17/datastream/OBJ/view