Hole Diameters on Sieve Trays

Hole diameters on industrial trays range from Vie to 1 in. In selecting 

Mass transfer In froth regime operation, small holes provide better vapor-liquid contact, and hence higher efficiency (119,172,184, 247, 252, 273, 317, 326, 347, 438, 439). The effect is small, and often negligible (119, 184, 218, 273, 326, 409). In the spray regime there is some indication that large holes enhance efficiency (273, 347), although this may not always apply (326). 

Frothing In clean vacuum services operating in the froth regime, small holes (Vs in diameter) have been specifically recommended for both entrainment and efficiency reasons (175, 257, 317). 

Turndown Small holes have a better turndown characteristic because they reduce tray weeping and increase tray capacity. 

Costs Trays punched with l2U ger holes are cheaper because fewer 

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