Equations Describing Simultaneous Reaction and Transport Processes

Equations Describing Simultaneous Reaction and Transport Processes 

Since it is obvious that the smooth variation of these quantities does not extend to the surface of catalyst pellets, much less through them, it must be explained that the smoothness has significance only for a succession of points that are in some sense in equivalent positions relative to the particles of packing. We might, for example, think of a network of points that are roughly in the centers of the holes among the pellets taking account only of these points, the temperature can be described as a fairly smooth function of position. An alternative network would be the points at the centers of catalyst pellets. 

As the statistical description of the packed bed must depend on some kind of averaging to represent the properties of the bed as functions of position, the property is averaged over a representative region having the 

There are two reasons for adopting a different attitude toward the apparent diffusion parallel to the flow. One is that in the reactors that 

From the point of view of practical computation, the equations without axial diffusion are solved by starting at the inlet to the reactor and computing the conditions stepwise downstream, making no adjustment for what happens further downstream. When there is axial diffusion, the conditions at all points in the reactor have to be adjusted to meet boundary conditions at both ends, and the difficulty of the computation is multiplied by a large factor. 

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III. Equations Describing Simultaneous Reaction and Transport Processes. . 211... 

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