CHE 408 Recitation 08 Problem 1 A distillation column separating ethanol from water is shown. Pressure is 1 kg/cm. Instead of having a reboiler, steam (pure water vapor) is injected directly into the bottom of the column to provide heat. The injected steam is a saturated vapor, which upon condensation mixes into the liquid in the column. The feed is 30 wt% ethanol and is at 20C. Feed flow rate is 100 kg/min. Reflux is a saturated liquid. We desire a distillate concentration of 60 wt% ethanol and a bottoms product that is 5 wt% ethanol. The steam is input at 100 kg/min. What is the reflux ratio, L/D? D.Xo S 8.48 Saturated steam specific enthalpy is its = 638 kcal/kg. The specific enthalpy data for various ethanol- water streams in the column are marked on the H-T-x-y chart in units of kcal/kg. Ax=408 $$studio A=92 A=65 A-8