Repeat Example 2-4, but with \(\mathrm{F}=3000 \mathrm{lbmol} / \mathrm{h}\), and use a horizontal flash drum with holding time \(=55 \mathrm{~min}\) and surge time \(=85 \mathrm{~min}\). Calculate \(\mathrm{D}, \mathrm{h}\), and \(\mathrm{h} / \mathrm{D}\).

Example 2-4

A vertical flash drum is to flash a liquid feed of 1500 lbmol/h that is 40 mol% n-hexane and 60 mol% n-octane at 101.3 kPa (1 atm). We wish to produce a vapor that is 60 mol% n-hexane. Solution of the flash equations with equilibrium data for y_H = 0.60 gives x_H = 0.19, T_drum = 378K, and V/F = 0.51. What size flash drum is required?