Distillation Design Questions and Answers – Constant Molar Overflow and Other Assumptions

This set of Distillation Design Question Bank focuses on “Constant Molar Overflow and Other Assumptions”.

1. The method of construction of an x-y diagram was explained by
a) Richardson and Coulson
b) Robinson and Gilliland
c) Murphree and Fenske
d) Cremer and Pullong
View Answer

Answer: b
Explanation: Pseudo properties were given by Robinson and Gilliland, while Murphree and Fenske gave equations to calculate trays and efficiency respectively.

2. Consider the following data, L’ = 363 and slope of section is 1.55. Estimate Vapor flow rate on either side
a) 234
b) 284
c) 303
d) 456
View Answer

Answer: a
Explanation: The slope is given by L’/V’=1.55, V’ = 363/1.55 = 234.

3. The point where equilibrium curve and component balance meets is called as
a) Murphree point.
b) Intersection point
c) Junction point
d) Pinch point
View Answer

Answer: d
Explanation: At infinite stages the where equilibrium curve and component balance meets is called as pinch point.

4. HETP is defined?
a) Height equivalent to theoretical plate
b) High efficiency tower plate
c) High energy temperature point
d) Homotomy Engineer Temperature Point
View Answer

Answer: a
Explanation: HETP is Height equivalent to theoretical plate, also defined as ratio of HTU (height of transfer units) and NTU.

5. The condition where reflux and stripping ratio approaches to infinity is called as
a) Minimum reflux
b) Total reflux
c) Optimum ratio
d) Feed ratio
View Answer

Answer: b
Explanation: Both balance lines approaches to coincide such a condition is called Total reflux, the slope of rectifying and stripping line matches each other.
Sanfoundry Certification Contest of the Month is Live. 100+ Subjects. Participate Now!

6. Which of following is an important assumption of McCabe Thiele method?
a) Heat loss is maximum
b) Heat loss is negligible
c) Heat loss is infinite
d) Can’t be specified
View Answer

Answer: b
Explanation: The major assumption of McCabe Thiele method is Heat loss is negligible and also an overhead reboiler and condenser are used to recover heat loss.

7. In which case Constant Molar overflow is true?
a) Equimolar counter diffusion
b) Equimolar co-current diffusion
c) Distinct overflow
d) Not Sure of Diffusion
View Answer

Answer: a
Explanation: CMO is totally based on the assumption of equal-molar counter diffusion, mainly used in the calculation of trays in the McCabe Thiele method.

8. In McCabe Thiele method, equilibrium line is drawn between
a) x-y
b) y-x
c) x*- y
d) y*-x
View Answer

Answer: a
Explanation: The equilibrium is always drawn between x-y mole ratios, where x is mole of liquid feed and y is the mole of gas at equilibrium conditions.

9. The equilibrium line is plotted on the graph at
a) Middle of both sections
b) 900 from stripping section
c) 450 from axis meet up
d) At meetup of axis
View Answer

Answer: c
Explanation: Equilibrium line is always plotted between axes at 450, while the 90 0 perpendicular is used to find the feed point on x-y graph.

10. The tray by tray approach method was given by
a) Sorel
b) McCabe
c) Fenske
d) Murphree
View Answer

Answer: a
Explanation: The oldest method of calculation was given by Sorel in 1893, Murphree gave equations for efficiency, Fenske for the minimum trays.

Sanfoundry Global Education & Learning Series – Distillation Design.
To practice Distillation Design Question Bank, here is complete set of 1000+ Multiple Choice Questions and Answers.

Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & discussions at Telegram SanfoundryClasses.