Distillation Design Questions and Answers Part-16

1. For a partial Condenser, the terms for middle diagonals are?
a) KIf and LiF
b) -(1+L1/KI1D)
c) -(Aij)
d) Aij

Answer: b
Explanation: For a partial Condenser the terms for middle diagonals -(1+L1/KI1D)=mi1 and Aij represents the factor of equilibrium.

2. For a partial Condenser, the terms for lower diagonals are?
a) -(1+L1/KI1D)
b) -(Aij)
c) L1/KI1D
d) Aij

Answer: c
Explanation: For a partial Condenser the terms for lower diagonals are L1/KI1D=Ai1 and L1/KI1D represents the equivalent to absorption factor.

3. For a reboiler stage N, the middle diagonal is
a) -(1+L1/KI1D)
b) KIf and LiF
c) L1/KI1D
d) -(1+B1/KI1VN)

Answer: d
Explanation: For a reboiler stage N the middle diagonal is-(1+B1/KI1VN), -(1+L1/KI1D) represents the next set of absorption factor of next + 1 stages.

4. For a total condenser, the reflux ratio just include
a) L1/KI1D
b) – (1+L1/D)
c) – (1+L1/KI1D)
d) – (Aij)

Answer: b
Explanation: For a total condenser the reflux ratio just include mij= – (1+L1/D), Where D is the distillate of the column and L is the liquid flow rate of column.

5. In matrix form, the total material balance equations are expressed as
a) F V=-R
b) RV=-F
c) L/V=F
d) V/R = F

Answer: b
Explanation: In matrix form the total material balance equations are expressed as RV= -F, this matrix can be solved either by determinant method or L U method.

6. In Thomas algorithm
a) Stage factor is calculated
b) Reflux factor is calculated
c) Feed factor is calculated
d) Boil up factor is calculated

Answer: a
Explanation: In Thomas algorithm Stage factor is calculated, in various other such as matrix method the reflux and the feed factor are to be calculated.

7. Forward elimination always starts from the
a) Right of corner
b) Middle of corner
c) Upper left corner
d) Last row

Answer: c
Explanation: Forward elimination always starts from the upper left corner, all elements are covered as the approach is from top to bottom.

8. Back substitution always starts from the
a) Lower right corner
b) Middle of corner
c) Upper right corner
d) Last row

Answer: a
Explanation: Back substitution always starts from the lower right corner and all elements are considered as the bottom to top approach method.

9. For Wide boiling mixtures, K value is
a) Different at different places
b) Same at different places
c) Specific at any time
d) Final Temperature based

Answer: a
Explanation: Wide boiling mixtures have K value is Different at different places, K value is independent of temperature, pressure and other affecting phenomena.

10. Each row acts as a
a) Different factor
b) Same factor
c) Coinciding factors
d) Elliptical Factor

Answer: a
Explanation: Each row acts as a Different factor, the pressure, temperature, volume all other factors are arranged in a separate column to differentiate between them.