Shape of packing units

Although bodies of various shapes have been proposed as packing, cylinders are by far the most usual form. Of the non-cylindrical types, balls and saddles are those most often encountered in the laboratory. Some of the other shapes that have been suggested are single-turn glass spirals, glass wool, chain links, tacks, nails, metal bellows. Data for packings are listed in Table 70. 

A double logarithmic plot of 0 vs. load (ml X h ) gives rectilinear dependences according to which the most efficient packing units may be chosen. Fig. 346 exhibits the data for new packing units developed by Keren [1 to 4) as compared to those for helices with close and wide spacing (-5 and 6). 

Comparison of the separating efficiency of various packing units (Ker6nyi [121]) 

Column 24 mm diameter, effective separating length 50 cm Pressure atmospheric Reflux ratio oo 

Cylindrical packing units (based on the Kaschig ring) 

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