We wish to flash distill a feed that is \(55.0 \mathrm{~mol} \%\) ethane and \(45.0 \mathrm{~mol} \% \mathrm{n}-\) pentane. \(\mathrm{p}_{\text {drum }}=700 \mathrm{kPa}\) and \(\mathrm{T}_{\text {drum }}=30.0^{\circ} \mathrm{C}\). Feed flow rate is \(100,000 \mathrm{~kg} / \mathrm{h}\).

a. Find \(\mathrm{V} / \mathrm{F}, \mathrm{V}\), L, liquid mole fraction, and vapor mole fraction.

b. Find the dimensions in feet required for a vertical flash drum. Assume the vapor is an ideal gas to calculate vapor densities. Use DePriester charts or Eq. (2-28) for VLE. Be careful with units. Arbitrarily pick \(\mathrm{h}_{\text {total }} / \mathrm{D}=4\), \(\mathrm{MW}_{\text {ethane }}=30.07, \mathrm{MW}_{\text {pentane }}=72.15\). Liquid densities: \(ho_{\mathrm{E}}=0.54 \mathrm{~g} / \mathrm{ml}\) (estimated), \(ho_{\mathrm{P}}=0.63 \mathrm{~g} / \mathrm{ml}\).

Equations (2-28)

Transcribed Image Text:

In K = a/T2+ a2 T + + pl In p + ap2/p + ap3/p