Page 232 - Air Pollution Control Engineering

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Wet and Dry Scrubbing 211

Table 2
Constants for Use in Determining Height of a Liquid Film Transfer Unit
2
Packing Y S Range of L'' (lb/h-ft )
Raschig rings
0.375 in. 0.00182 0.46 400–15,000
0.5 in. 0.00357 0.35 400–15,000
1 in. 0.0100 0.22 400–15,000
1.5 in. 0.0111 0.22 400–15,000
2 in. 0.0125 0.22 400–15,000
Berl saddles
0.5 in. 0.00666 0.28 400–15,000
1 in. 0.00588 0.28 4OO-15,000
1.5 in. 0.00625 0.28 400–15,000
3-in. Partition 0.0625 0.09 3,000–14,000
rings (stacked,
staggered)
Spiral rings (stacked, staggered)
3-in. Single spiral 0.00909 0.28 400–15,000
3-in. Triple spiral 0.0116 0.28 3,000–14,000
Drip-point grids (continuous flue)
Style 6146 0.0154 0.23 3,500–30,000
Style 6295 0.00725 0.31 2,500–22,000
Source: ref. 11.

Table 3
Schmidt Numbers for Gases and Vapors in Air at 77°F and 1 atm
Substance Sc a Substance Sc a
G G
Ammonia 0.66 Valeric acid 2.31
Carbon dioxide 0.94 i-Caproic acid 2.58
Hydrogen 0.22 Diethyl amine 1.47
Oxygen 0.75 Butyl amine 1.53
Water 0.60 Aniline 2.14
Carbon disulfide 1.45 Chloro benzene 2.12
Ethyl ether 1.66 Chloro toluene 2.38
Methanol 0.97 Propyl bromide 1.47
Ethyl alcohol 1.30 Propyl iodide 1.61
Propyl alcohol 1.55 Benzene 1.76
Butyl alcohol 1.72 Toluene 1.84
Amyl alcohol 2.21 Xylene 2.18
Hexyl alcohol 2.60 Ethyl benzene 2.01
Formic acid 0.97 Propyl benzene 2.62
Acetic acid 1.16 Diphenyl 2.28
Propionic acid 1.56 n-Octane 2.58
i-Butyric acid 1.91 Mesitylene 2.31
a Sc =µ / P D , where D and µ are the density and viscosity of the gas stream, respectively, and
G G G G G G
P is the diffusivity of the vapor in the gas stream.
G
Source: ref. 13.