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" Modeling of multicomponent gas-solid reactions "
A. I. Abba
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Latin Dissertation
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English
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| Record Number
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1112815
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TLpq231508730
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| Main Entry
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A. I. Abba
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| Title & Author
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Modeling of multicomponent gas-solid reactions\ A. I. Abba
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| College
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King Fahd University of Petroleum and Minerals (Saudi Arabia)
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| Date
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1995
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| student score
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1995
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| Degree
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M.S.
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| Page No
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170
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| Abstract
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A generalized multicomponent gas-solid reaction model is developed based on the particle-pellet model that considers the transient nature of the system, inter and intra particle heat and mass transfer and the variation of structural parameters with reaction. The principal significance of such model is in its integration in the design and simulation of a number of commercially important operations. This model can be used in the modeling of both catalytic and non catalytic gas-solid reactions. The computer coding developed is implemented following Newton's method. The Gauss-Jordan complete elimination method with maximum pivot strategy is employed in solving the set of linearized equations that resulted from the principal model equations. The model is validated by comparing simulation results with experimental data for carbon gasification reaction over the temperature range of 900C-1100C and reduction of NiO/Fe2O3 mixture at 581 K and 608 K respectively. The match between model and experiment was found to be satisfactory in general. Multicomponent simulation results are also presented herein, that resulted from a scenario in which four sequential reactions (carbon gasification, reduction of nickel oxide/hematite mixture and water gas shift reaction) are considered to be taking place simultaneously. From the analysis of the effects of external and internal mass and heat transfer, it was found that, the reactions studied are both diffusion and kinetic controlled, i.e., intermediate regime, in which the magnitude of each varies with the individual reactions. It is established that, the external mass and heat transfer effects are negligible for the pellet size studied. A detailed parametric study is carried out, in which the effects of bulk temperature, bulk pressure, inert gas in the bulk stream, pellet porosity and inert solid inside pellet matrix are clearly demonstrated. The established effects are found to be consistent with theoretical observations. The model developed can, therefore, be integrated in the design and simulation of Fluidized Bed Reactors, Packed Towers and for control purposes among others.
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Applied sciences
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Chemical engineering
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Chemical engineering
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Mechanical engineering
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