Random dumped packings

Once packing heights are determined in other sections from HETP (distillation) or Koa (absorption), the height allowances for the internals (from Figure 1) can be added to determine the overall column height. Column diameter is determined in sections on capacity and pressure drop for the selected packing (random dumped or structured). 

Tlie flood pressure drop for structured packing, already shown in the subsection on random dumped packings, is repeated here ... 

Figure 9-24B. Packing factors (screen packing and random dumped packing). Used by permission of U.S. Stoneware Co. (now, Norton Chemical Process Products Corp.).

A Norton [139] correlation for modern, random dumped packings used for distillation up to 200 psia is (use high performance internal distributors and supports) from surface tension of 4 dynes/cm but less than 33, and liquid viscosity of at least 0.83 to 0.08 cps but not greater ... 

HETP values for random dumped packing have been found to be 25% greater at a greater ascosity than a lower viscosity, i.e., viscosity change from 0.15 cps to 0.44 cps. 

A useful graphical correlation for flooding rates was first presented by Sherwood et a/.(60) and later developed by Lobo el al.(6l> for random-dumped packings, as shown in Figure 4.17 in which ... 

Random or dumped packings (Figs. 14-48 and 14-49) are discrete pieces of packing, of a specific geometric shape, that are dumped or randomly packed into the column shell. 

As an alternative to trays, especially at low volumetric liquid-to-vapor ratios, packing can be used to promote vapor-liquid contact. One approach is to dump specially shaped pieces of metal, glass, or ceramic material into the column, wherein they are supported on a grid. An example of dumped or random packing is shown in Fig. 7. 

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