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Unformatted text preview: from Eq. (79), of R/(R + 1) = 0.5/1.5 = 0.333. This operating line passes through the point, y = 0.8, x = 0.8. From Eq. 79), the equation for the rectifying section operating line is,
y= R 1 x+ x D = 0.333x + 0.667(0.8) = 0.333x + 0.533 R +1 R +1 From this equation, the intersection of the rectifying section operating line and the vertical qline is at y = 0.333(0.5) + 0.533 = 0.70. The stripping section operating line passes through the {y, x} points {0.70, 0.50} and {0.25, 0.25}, giving it the equation, y = 1.80x0.20. Except for the reboiler stage, the stages are stepped off from an efficiency line, which for a Murphree vapor efficiency of 0.5 is positioned vertically half way between the equilibrium curve and the operating line, as governed by Eq. (741), EMV = 0.5 = (yn  yn+1)/(yn*  yn+1), where yn+1 is the location on the operating line, yn is the location on the efficiency line, and yn* is the location on the equilibrium line. However, the reboiler is assumed to have a 100% efficiency. As seen in the plot, just over 8 trays a...
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This note was uploaded on 09/08/2008 for the course CHE 244 taught by Professor Selebi during the Spring '06 term at Lehigh University .
 Spring '06
 selebi
 Distillation, pH, Mass Transfer

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