Hollow finite cylindrical catalysts are becoming of more interest as catalyst support not only because they produce lower pressure drops than with conventional solid pellets but also because they provide the associated extra external surface area which enhances diffusion-limited reactions. Dynamic simulation of diffusion, conduction and reactions in this type of catalyst has been studied. The numerical method, Alternating Direction Implicit Method (ADIM), has been used for solving the coupled elliptic governing equations. The simulation applied to methane-steam reforming involves multiple (parallel) reactions and multicomponent mixtures of products and reactants within the catalyst. The numerical method proposed is expected to be capable of following steep gradient of methane concentration across the cylindrical catalyst during methane-steam reforming. From a critical literature evaluation of kinetics of methane-steam reforming, it was found that the data of Bodrov et al. (1967a) and that of Kopsel and Meyer (1980) were obtained from experiments in the temperature range of industrial application. The ADIM was able to follow, successfully, the steep gradient of methane concentration during methane-steam reforming by employing kinetic expressions derived by Kopsel and Meyer (1980) within hollow, finite cylindrical catalyst. The numerical method has been used for comparative study of temperature and concentration profile across the catalyst by employing several kinetic expressions for methane-steam reforming. The kinetic expressions of Bodrov et al (1967a), modified by comprehensively reinterpreting their data, also produce diffusion-controlled profiles across the hollow finite cylindrical catalyst. The comparative study found that the kinetic expressions of De Deken et al (1982) and the more elaborate kinetics of Xu and Froment (1989) do not produce diffusion-controlled profile across the catalyst at high temperature.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:639049 |
| Date | January 1994 |
| Creators | Sitompul, J. P. |
| Publisher | Swansea University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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