We are separating ethanol and water. All percentages are mol\%. Column pressure is at \(1.0 \mathrm{~atm}\). VLE data are in Table 2-1. Find the q values and plot the feed lines for the following situations:

a. Feed is \(60 \%\) ethanol and flashes in the column with \(\mathrm{V} / \mathrm{F}=0.37\).

b. Feed is \(40 \%\) ethanol and is a two-phase mixture with liquid and vapor in equilibrium at a temperature of \(84.1{ }^{\circ} \mathrm{C}\).

c. Feed is \(40 \%\) ethanol and is a liquid at \(20^{\circ} \mathrm{C}\).

d. Feed is \(40 \%\) ethanol and is a vapor at \(120^{\circ} \mathrm{C}\).

e. Feed is \(50 \%\) ethanol and is a subcooled liquid. One mole of vapor must be condensed to heat 12 moles of feed to their boiling point.

f. Feed is \(20 \%\) ethanol, and \(70 \%\) is vaporized in a flash distillation system. The products of the flash system are fed separately to different feed stages. Calculate the two \(\mathrm{q}\) values, and plot the two feed lines.

Transcribed Image Text:

TABLE 2-1. Vapor-liquid equilibrium data for ethanol and water at 1 atm y and x in mole fractions XEtoh Xw YEtoh Yw T, C 0 1.0 0 1.0 100 0.019 0.981 0.170 0.830 95.5 0.0721 0.9279 0.3891 0.6109 89.0 0.0966 0.9034 0.4375 0.5625 86.7 0.1238 0.8762 0.4704 0.5296 85.3 0.1661 0.8339 0.5089 0.4911 84.1 0.2337 0.7663 0.5445 0.4555 82.7 0.2608 0.7392 0.5580 0.4420 82.3 0.3273 0.6727 0.5826 0.4174 81.5 0.3965 0.6035 0.6122 0.3878 80.7 0.5079 0.4921 0.6564 0.3436 79.8 0.5198 0.4802 0.6599 0.3401 79.7 0.5732 0.4268 0.6841 0.3159 79.3 0.6763 0.3237 0.7385 0.2615 78.74 0.5732 0.4268 0.6841 0.3159 79.3 0.6763 0.3237 0.7385 0.2615 78.74 0.7472 0.2528 0.7815 0.2185 78.41 0.8943 0.1057 0.8943 0.1057 78.15 1.00 0 1.00 0 78.30