Nature and Effects of Maldistribution

A detailed discussion of packed-tower maldistribution is far too bulky for inclusion here and is available elsewhere (e.g., 160, 183, 221, 222, 442, 443). Conclusions which specifically pertain to distribution equipment practices are highlighted below  

A packed column has reasonable tolerance for a uniform or smooth variation in liquid distribution and for a variation that is totally random ( small-scale maldistribution ). However, the impact of discontinuities or zonal flow ( large-scale maldistribution ) is much more severe (219, 221, 222, 442, 443). 

A packed bed appears to have a natural distribution, which is an inherent and stable property of the packings (1, 160, 221, 386, 442). An initial distribution which is better than natural will rapidly degrade to it, and one that is worse will finally achieve it, but sometimes at a very slow rate. If the rate is extremely slow, recovery from a maldistributed pattern may not be observed in practice (221, 222). 

Three factors appear to set the effect of maldistribution on efficiency (160, 193, 284, 443)  

At small tower to packing diameter ratios ( 10), the effect of lat- 

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