Comparison of the Common Tray Types

Rgure 6.2 Flow through tray vapor passes, (a) Bubble-cap tray, (6) sieve tray c) valve tray, tM. Van WinkU, Distillation, Copyright 1967 by McGraw-Hill Inc., reprinted by permission.) 

The turndown of v ve trays is much better than sieve trays, but not as good as bubble-cap trays. Bubble-cap trays are the most suitable to handle extremely low liquid rate applications [less than 2 gpm per foot of average flow width (10)]. 

The cost of bubble-cap trays is by far the highest. Sieve trays are the least expensive, but valve trays are only slightly more expensive. 

Type Sieve tray Valve tray Bubble-cap tray Dual-flow tray 

Capacity High High to veiy high Moderately high Very high 

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TABLE 6.1 Comparison of the Common Tray Types (Conr/mNKQ... 

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