lista completa de exercícios (1)

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Lista de exercícios Destilação 
1-Exercise 
Cooling of a reactor effluent with recycled liquid. Figure 1 shows a system to cool 
reactor effluent and separate light gases from hydrocarbons. K-values at 500 psia and 
100ºF are: 
 
 
Figure 1. Conditions for Exercise 1. 
(a) Calculate composition and flow rate of vapor leaving the flash drum. (b) Does the 
liquid-quench flow rate influence the result? Prove your answer analytically. 
 
2-Exercise 
A column at 101 kPa is to separate 30 kg/h of a bubble-point solution of benzene and 
toluene containing 0.6 mass-fraction toluene into an overhead product of 0.97 mass-
fraction benzene and a bottoms product of 0.98 mass-fraction toluene at a reflux ratio of 
3.5. The feed is sent to the optimal tray, and the reflux is at saturation temperature. 
Determine the: (a) top and bottom products and (b) number of stages using the following 
vapor–liquid equilibrium data. 
 
Ans: a) D = 12.1 kg/h B = 17.9 kg/h 
b) 10 stages + a partial reboiler acting as an equilibrium stage are required. 
 
3-Exercise 
 A mixture of 54.5 mol% benzene in chlorobenzene at its bubble point is fed continuously 
to the bottom plate of a column containing two equilibrium plates, with a partial reboiler 
and a total condenser. Sufficient heat is supplied to the reboiler to give Vm+1/LM = 0.855, 
and the reflux ratio LN/VN+1 in the top of the column is constant at 0.50. Under these 
conditions using the equilibrium data below, what are the compositions of the expected 
products? 
 
Ans: benzene, xD = 0.90 and xB = 0.28. 
 
4-Exercise 
 
 
5-Exercise 
 
6-Exercise 
 
4,7 theoretical plates 
 
 
 
Lista de Ponchon Savarit 
1-Exercise 
 
2-Exercise 
 
 
 
3-Exercise 
 
 
 
 
 
 
4-Exercise 
 
 
 
5-Exercise 
One hundre pound-moles per hour of a mixture of 60 mole% metanol in water at 30ºC and 
1 atm is to be separated by distillation at the same pressure into a distillate containing 98 
mole% methanol and a bottoms product containing 96 mole% methanol and a bottoms 
product containing 96 mole% water. The overhead condenser will produce a subcooled at 
40ºC determine by the Ponchon method: 
a) the minimum cold external reflux in moles per mole distillate. 
b) The number of theoretical stages required for total reflux. 
c) The mumber of theoretical stages required for a cold external reflux of 1.3 times the 
minimum. 
d) the internal reflux ratio leaving the top stage, the stage above the feed stage, the stage 
below the feed stage, and the bottom stage leading to reboiler. 
e) The duties in BTU/hr of the reboiler and condenser. 
f) The temperature of the top stage and the feed stage. 
g) All the items in part (c) to (f) if a boilup ratio of 1.3 times the minimum value is used. 
 
 
 
 
 
 
 
6-Exercise