The ratio of Murphree plate efficiency to point efficiency is 1 in a __________ flow model.
A. Plug
B. Perfectly mixed
C. Both A & B
D. Neither A nor B
Answer: Option B
This Question Belongs to Chemical Engineering >> Mass Transfer
Join The Discussion
Comments (1)
Related Questions on Mass Transfer
A. Chemical properties
B. Physical properties
C. Degree of turbulence
D. Interfacial area
A. No change in theoretical
B. Marginal decrease in the number of
C. Major decrease in the number of
D. None of these
The correct answer is: A. Plug
Explanation:
Murphree Plate Efficiency accounts for the efficiency of a tray considering the overall composition change of the vapor across the tray.
Point Efficiency considers the local mass transfer efficiency at a specific point on the tray.
Flow Models:
Plug Flow Model (ideal flow without mixing across the tray):
The composition is uniform in the direction of flow.
In this case, Murphree plate efficiency = Point efficiency, so the ratio is 1.
Perfectly Mixed Model:
Vapor is assumed to be completely mixed across the tray.
Murphree plate efficiency is less than point efficiency due to back-mixing effects.
Therefore, the correct choice is:
A. Plug