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Gewählte Master / Diploma Thesis:

Paul Julius Wilhelm Beer (2019): Einfluss von Rohrbündelwärmetauschern auf die Partikelverweilzeit und das Mischungsverhalten in blasenbildenden Wirbelschichten.
Master / Diploma Thesis - Institut für Verfahrens- und Energietechnik (IVET), BOKU-Universität für Bodenkultur, pp 74. UB BOKU obvsg FullText

Data Source: ZID Abstracts
Abstract:
Bubbling fluidized beds are known for their favorable heat transfer and mixing habits and can thus be used as a method to capture carbon from flue gases. An existing cold flow model at the Institute for Chemical and Energy Engineering at the University of Natural Resources Vienna was used to perform experiments regarding the influence of heat pipes, which were placed into the fluidized bed, on the mixing habits inside the reactor. The bed was filled with glass particles and tracers in the form of ferromagnetic steel particles,both with similar fluid dynamic characteristics and part of Geldart Group B. The tube bundles were placed into the bed in three different formations. Initial measurements were completed with the empty bed and afterwards with the tube bundles and a void ratio of ψ=0,71. Finally, measurements were carried out with a void ratio of ψ=0,53. Within the measurements, the particle circulation rate and the fluidization rate were varied. The system that was used was an inductive one. Resulting data was then edited via MATLAB under the assumption that the cold flow model was reacting according to a ideal plug flow reactor with axial dispersion connected in series with an ideally stirred tank reactor. The resulting Efit-curve was then created by mathematical convolution and used to get all the characteristic values, which describe the mixing phenomena inside the bubbling fluidized bed. The results show that, due to the modification the separation of tracer and gals particles could be improved. Furthermore, it's shown that the particle circulation rate as well as the fluidization rate of the bed have an impact on the mixing behavior of the reactor. Therefore, dead zones were found when the fluidization was low, but could be reduced by increasing the fluidization. According to the tube bundles, it can be said that they reduce the mixing process within the bed by decreasing void ratio. However, this can be counteracted with higher fluidization gas flow rates.

Beurteilende(r): Pröll Tobias
1.Mitwirkender: Hofer Gerhard

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