CALLIBRATION DATA :

ml of water(VB)	ml of methanol (VA)	Mole fraction of methanol (X)	RI
100	0	0	1.33
90	10	0.059	1.3315
80	20	0.1233	1 .3325
70	30	0.194	1.3345
60	40	0.273	1.3336
50	50	0.36	1.337
40	60	0.458	1.3345
30	70	0.568	1.337
20	80	0.69	1.3345
10	90	0.837	1.3305
0	100	1	1.3235

 

Fit RI vs mole fraction curve and find out to ploynomials ,one for the water rich section(bottom composition) and the other for the methanol rich section(distillate composition).

Formulae :

 

Intercept =

Overall effeciency of the packed distillation column =    

Observation and calculations :

RI of feed =1.337

RI of distillate =1.3345

From the calibration curve corresponding mole fraction of methanol are :

Xf =0.5

XD =0.8

L/D =1(say)

Intercept =0.4

Average value of realtive volatilty for methanol - water system is 3.32

Using the x-y data for methanol - water system available in perry we construct the McCabe- thiele diagram with the above given data and strike of the number of equilibrium stages

Total no. of ideal stages(including reboiler)=7

No. of ideal stages reqd. NT-1 = 6

No. of actual stages = 7

Therafore Overall effeciency of the packed distillation column = 85.7%