| Summary: | Steam reforming of methane is a highly endothermic, reversible and fast reaction. It is industrially performed in fixed bed configuration with relatively large catalyst pellets to avoid excessive pressure drop. The diffusional limitations in the catalyst pellets are quite severe, giving rise to effectiveness factors, η, in the range 10−2 – 10−3.Elnashaie and Adris suggested the use of a fluidized bed configuration for this reaction. The fluidjized bed configuration offers obvious advantages for this reaction, since the powder catalyst used in the bed gives rise to η = 1. Therefore, increasing the actual rate of reaction two to three folds. In this paper a modified model is developed for this fluidized bed where the material balance equations are formulated to calculate molar flow rates of reactants and products in the bubble and dense phases, instead of concentrations. The model therefore, treats the change in number of moles in a more rigorous basis than the model of Elnashaie and Adris.The predictions of the present more rigorous model confirms the results and conclusions of the earlier study using the simpler model. It also shows that the predicted improvement of fluidized bed over fixed bed is higher using this more rigorous model. The role of the bubbles in removing the reaction products from the active dense phase is also emphasized.
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