# 4 04 the rectifying section operating line intersects

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Unformatted text preview: equilibrium curve and the q-line intersect. The slope of that line is measured to be L/V = 0.642. From Eq. (7-9), L/V = R/(R + 1). Rearranging, Rmin = (L/V)/[1 - (L/V)] = 0.642/(1 - 0.642) = 1.79 The stripping section operating line intersects the point {0.05, 0.05} and the point where the equilibrium curve and the q-line intersect. The slope of that line is measured to be L / V = 2.043. From Eq. (7-14), L / V = (VB + 1)/VB. Rearranging, V 1 1 = = = 0.959 (VB )min = B min ( L / V ) - 1 2.043 - 1 The McCabe-Thiele plot for minimum stages at total reflux is also shown on the next page. The operating lines are coincident with the 45o line. It is seen that 6 equilibrium stages are needed. (b) For a reflux ratio, R = L/D, of 4, the slope of the rectifying section operating line from Eq. (7-9) is L/V = R/(R + 1) = 4/5 = 0.8. This line and the stripping section operating line are shown on the third McCabe-Thiele diagram below. Except for the reboiler stage, the stages are stepped off from an efficiency line, which for a Murphre...
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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 .

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