الفهرس 
Pertinent backgroung and Literature SurveyOnly 14 pages are availabe for public view
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Abstract
Modeling of fixed-bed catalytic reactors is of great importance. Three industrial high¬temperature shift (HTS) reactors operated at 32-35 bar at temperatures above 330 DC were considered as a case study. Copper-promoted catalyst of pellet size 6 x 6 mm was used.
A detailed assessment of heat and mass transfer effects is given. The one-dimensional pseudohomogeneous model has been implemented in MA ’fLAB to solve the governing equations and compare the solution with measured conversion and temperature profiles.
Catalyst sintering was considered while developing the reactor model. The corrected frequency factor as a function of time and temperature was best described by the
hyperbolic equation k: =4A.[1+a •. exp(-Ew/RT)JlQ, whereA. =8xl06s-l, E”=169 kJ mor1, q = Y3, and a.is a variable in the range (e27.S to e29.5) h-1• It was found that catalyst sintering is rapid during the first five months of operation and is slow during the next three years then becomes more or less constant for extended life time.
The software was used to understand some factors that are related to the process. The effect of catalyst type, inlet temperature, pellet size and pressure drop was studied.
In a reactor using a classic catalyst (6 x 6 mm), copper-promoted type can be charged instead to lower the HTS inlet temperature and so obtain a higher CO conversion. The plant energy consumption will be reduced. The client has the opportunity to choose between 20 % catalyst volume reduction and larger pellets, 9 x 6 mm, (with the same bulk volume) to obtain a lower pressure drop and maintain the required exit CO conversion.