Learning Based Problem

You are undergraduate student, your colleague and you have went to a nearby chemical plant as a scientific visit with your instructor. The chemical plant has a distillation process. The operating Engineer there described the process to you in details as follow: The distillation process separates phenol from ortho$-$cresol.

Two feed streams, each with a flow rate of $100mo\frac{l}{h}r$

$F_1,$ is a saturated liquid feod stream containing $60$ mole percent phenol

$F_2,$ is a saturated liquid feed stream containing $40$ mole percent phenol

Distillate should contain $99$ mole percent of phenol $)$

Bottom product should contain $1$ mole percent phenol $)=(0\mathrm{.}01$

The two streams, $F_1$ and $F_2,$ are mixed together and introduced to the column at the optimal location. Assume that after mixing, the feed to the column is a saturated liquid. The column has a partial reboiler and a total condenser.

a$.$ Why do they choose distillation process to separate phenol from ortho$-$cresol.

b$.$ Find the vapor$-$liquid equilibrium data for this process.

c$.$ We now want to run the column at a reflux ratio $1\mathrm{.}2$ times the minimum reflux ratio, determine the number of plates required for the separation.

d$.$ Determine the minimum number of stages for this process.

After that, your instructor ask you a question: If the two feed streams are entered to the column directly each at its optimal location, how many number of plates you need for the given separation and at which plate should you added each feed streams? How do you compare the obtained results?

The following vapor pressure was obtained for phenol and ortho$-$cresol:

$\backslash$table$[[\backslash$table$[[$Temp$.],[($K$)]],\backslash$table$[[$Vapor pressure of ontho$-$cresol$],[($kPa$)]],\backslash$table$[[$Vapor pressure of phenol$],[($kPa$)]]],[387,7\mathrm{.}7,20\mathrm{.}35],[387\mathrm{.}9,7\mathrm{.}94,20\mathrm{.}75],[388\mathrm{.}7,8\mathrm{.}21,21\mathrm{.}15],[389\mathrm{.}6,8\mathrm{.}5,21\mathrm{.}55],[390,8\mathrm{.}76,21\mathrm{.}95],[391\mathrm{.}1,9\mathrm{.}06,22\mathrm{.}35],[391,9\mathrm{.}4,22\mathrm{.}75],[392\mathrm{.}7,9\mathrm{.}73,23\mathrm{.}25],[393\mathrm{.}3,10\mathrm{.}0,23\mathrm{.}65]]$