The expanded bed adsorption (EBA) process naturally assumes a mixed bed (MB) in terms of particle size and displays particle dispersion. To date models have not accounted for this simultaneously and accurately. Moreover, there has not been any work to predict an adsorption response when the bed is in a hydrodynamic-transient state which occurs for example while changing feedstock. A series of MB steady state hydrodynamic EBA models were developed which are increasingly close mimics of reality. This was achieved by progressively considering: a single representative equivalent particle size per axial position (MBEQD), separate particle size categories by using size-partition (MBSP) approach and inclusion of an additional component flux due to particle dispersion. Breakthrough predictions using the MB approach were more accurate compared to both that of a mono-sized bed and perfectly classified bed approaches clearly demonstrating its importance. The results of both MBEQD and MBSP were in close agreement with 40 cm bed height breakthrough experimental data. An important weakness in an existing method of including the particle dispersion was identified and a model for its more accurate representation developed. A transient hydrodynamic EBA model was developed by integrating the mono-sized transient hydrodynamic model and adsorption model. A simulation study using this demonstrated the possibility of loading while a bed is still expanding which may afford an increase in an operational throughput. The effects of various physical parameters on the performance of EBA were investigated using simulation. Windows of operation in relation to fluid velocity and load volume were determined which would satisfy minimum yield and throughput criteria. The model was also used to determine optimal loading time strategies in order to maximise yield and throughput. Finally a preliminary work explaining future potential developments in EBA modelling was performed.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:498695 |
Date | January 2007 |
Creators | Maskey, Sabin Raj |
Publisher | University College London (University of London) |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://discovery.ucl.ac.uk/1446024/ |
Page generated in 0.0109 seconds