Page 120 - Separation process engineering

Since eq0 ~ 0, the answer to this flash problem is x = 0.1555 and y = 0.5167.

2.B.3 Multicomponent Flash Distillation with Excel

If VLE data are available in equation form, spreadsheet calculations can also be used for multicomponent
flash distillation. These calculations are illustrated for a chemical mixture that follows Eq. (2-16) for
Problem 2.D16. First, the spreadsheet is shown in Figure 2-B3 with the equations in each cell. Cells B3
to B6, C3 to C6, D3 to D6, E3 to E6, F3 to F6, and G3 to G6 are the constants for Eq. (2-16) from Table

2-3. Conditions for the operation are input in cells B7, D7, and F7, and the feed mole fractions are in
cells B8, C8, F8, and G9. Eq. (2-16) is programmed for each component in cells B10, B11, B12, and
B13. Then the liquid mole fractions are determined from Eq. (2-38) in cells B15 to B18. These four
numbers are summed in cell B19. The Rachford-Rice terms from Eq. (2-42) for each component are
calculated in cells B20 to B23, and the sum is in B24.
Figure 2.B-3. Spreadsheet for Multicomponent Flash for Problem 2.D16 with Equations in Each
Cell.