Distillation Design Questions and Answers Part-13

1. Jafarey, Dougles and Mcavoy Equation is capable of predicting
a) Column performance
b) Column feed rate
c) Column design
d) Column diameter

Answer: a
Explanation: Jafarey, Dougles and Mcavoy Equation is capable of predicting Column performance and control of disturbances.

2. The term PLK stands for
a) Primary left key
b) Pseudo Left key
c) Pseudo light key
d) Pressure light key

Answer: b
Explanation: The term PLK stands for Pseudo Left key, which indicated the components which are heavy key and are separated at left side.

3. PHK and PLK are also applied in
a) Hengstebeck’s equation
b) Fenske’s equation
c) Gilliland equation
d) Homotomy equation

Answer: a
Explanation: PHK and PLK are also applied in Hengstebeck’s method, while Fenske’s equation uses the relative volatility.

4. Jafarey Equation is an analytical closed form formula, to calculate
a) Reflux ratio
b) Number of trays
c) Number of stages
d) Number of feeds

Answer: b
Explanation: Jaffrey Equation is an analytical closed form formula to calculate Number of trays simplifying smoker’s equation.

5. In Jafarey Equation, N is predicted with an error of
a) ± 2 to 3
b) ± 1 to 2
c) ± 6 to 7
d) Can’t be specified

Answer: a
Explanation: In Jafarey Equation N is predicted with an error of ± 2 to 3 stages, this is an ideal error with respect to human and conservative errors that occur.

6. PHK stands for
a) Pre Heavy key
b) Pseudo Heavy key
c) Primary Heavy key
d) Pressure Heavy key

Answer: b
Explanation: PHK stands for Pseudo Heavy key representing the bottom end products which are removed at the bottom of column.

7. Dougles equation is useful for
a) Binary separations
b) Multicomponent separations
c) Tertiary Separations
d) Cant’ be specified

Answer: b
Explanation: Dougles equation is useful for multicomponent separations extended form of smoker’s equation.

8. Calculate ln S? If XLK=0.95 and XHK = 0.05 and XL= 0.90 and XH= 0.10, then
a) 6.77
b) 5.142
c) 7.898
d) Can’t be calculated

Answer: b
Explanation: as ln (0.95/0.05) (0.90/0.10) = 5.142.

9. Solve the following equation 0.3089R2 – 0.4033R – 0.1242=0?
a) 2.45
b) 1.31
c) 8.9
d) 7.8

Answer: b
Explanation: Using quadratic formula f(x) =0.3089R2 – 0.4033R – 0.1242, and at f (1.31) = 0 we can conclude and thus R=1.31.

10. The overall column efficiency is defined as
a) Nthoretical/Nactual
b) Nthoretical*Nactual
c) Nthoretical=Nactual
d) Nactual + 1

Answer: a
Explanation: The overall column efficiency is defined as Eoverall = Nthoretical/Nactual, whereas Nactual + 1 gives the real number of trays in a column.