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McCabe-Thiele Diagrams: Example Problem

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Example Problem 1

Acetone and ethanol are separated using a distillation column with a partial condenser and partial reboiler. An equimolar, sub-cooled liquid feed enters at 100 kmol/hr and condenses 1 mol of vapor for every 6 mol of feed. The separation requires a distillate vapor that is 95 mol% acetone and bottoms liquid that is 5 mol% acetone. The reflux is returned from the condenser to the column as a saturated liquid and the operation is run at (L/V) =1/4*(L/V)min. Assume constant molar overflow conditions. Perform the following:

  1. Plot the operating lines for the rectifying and stripping sections and the feed line.
  2. Determine the number of equilibrium stages required and number of trays if each tray has an efficiency of 1.
  3. Determine the optimal feed location.
  4. Determine the molar flow rates in and out of the condenser (V and D) and boiler (L and B).