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Question 11.3: For the problem specified in Example 11.2, estimate the numb...

For the problem specified in Example 11.2, estimate the number of ideal stages required below an acetone concentration of 0.04 (more volatile component), using the Robinson- Gilliland equation.

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From the McCabe-Thiele diagram in Example 11.2:

slope of bottom operating line, s^{\prime} = 5.0

slope of equilibrium line, K^{\prime} = 12.8

 

x_{b}=15.5 \times 10^{-6}

 

N_{s}^{*}=\frac{\log \left[\frac{\left(\frac{12.8}{5.0}-1\right)\left(\frac{0.04}{15.5 \times 10^{-6}}-1\right)}{\left(\frac{1}{5.0}\right)(12.8-1)}+1\right]}{\log \left(\frac{12.8}{5.0}\right)}+1=8.9, \text { say } 9 (11.25)

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