7 carry out the calculations at the bottom tray based

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: rate, kmol/h Molecular weight Density, kg/m3 Gas 630 18.5 0.657 Liquid 1,192 18.0 940 Estimate liquid diffusivity of methanol in water at 212oF = 373 K. From Perry's Handbook, DL = 1.6 x 10-5 cm2/s at 25oC. The viscosity of water at 212oF = 0.25 cP. Using Eq. (3-39) to correct for temperature and viscosity, DL = 1.6 x 10-5 (373/298)(1/0.25) = 8 x 10-5 cm2/s Estimate gas diffusivity of methanol in water vapor from Eq. (3-36). T = 373 K MAB = 2/[(1/32) + (1/18)] = 23. Using Table 3.1, = 15.9 + 2.31(4) + 611 = 31.3, . = 131 . V V methanol water 0.00143(373)1.75 DV = = 0.30 cm2/s 1/ 2 1/ 3 1/ 3 2 (151 / 14.7)23 [31.3 + 131 ] . . Required tray dimensions: DT = 6 ft, A = 3.14(6)2/4 = 28.3 ft2 = 2.63 m2 Aa = 0.91 A = 0.91(2.63) = 2.39 m2 = 23,900 cm2, Lw = 42.5 in. = 1.08 m Tray conditions: = 1 - 0.617 = 0.383, qL = 47,300/(60)(8.33) = 94.6 gpm = 5,970 cm3/s From Eq. (6-54), Cl = 0.362 + 0.317 exp[-3.5(2)] = 0.362 From Eq. (6-51), f = 0.40, 94.6 hl = 0.383 2.0 + 0.362 (42.5)(0.383) 2/3 = 1.21 in. =...
View Full Document

This note was uploaded on 09/08/2008 for the course CHE 244 taught by Professor Selebi during the Spring '06 term at Lehigh University .

Ask a homework question - tutors are online