A sieve-tray tower is to be designed for distillation of a mixture of toluene and methylcyclohexane. The circumstances which are to be used to establish the design are

The equilibrium data at this concentration indicate that $m=1.152$.

(a) Design a suitable cross-flow sieve tray for such a tower. Take $d_{0}=4.8 \mathrm{~mm}$ on an equilateral-triangular pitch $12.7 \mathrm{~mm}$ between hole centers, punched in stainless-steel sheet metal $2 \mathrm{~mm}$ thick. Use a weir height of $50 \mathrm{~mm}$. Design for a $60 \%$ approach to the flood velocity. Report details respecting tower diameter, tray spacing, weir length, gas-pressure drop, and entrainment in the gas. Check for excessive weeping.

(b) Estimate the tray efficiency corrected for entrainment for the design reported in part (a).

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Temperature = 380 K Pressure 98.8 kPa Liquid: Rate = 4.8 mol/s Composition = 48.0 mol% toluene Density 726 kg/m Surface tension = 16.9 dyn/cm Diffusivity = 7.08 10-5 cm/s (est.) Vapor: Rate 4.54 mol/s = Density = 2.986 kg/m Diffusivity 0.0386 cm/s (est.) Viscosity = 0.22 cP Foaming factor = 0.80 Composition =44.6 mol% toluene = Viscosity 337 P (est.)