____________ is the determining factor for the number of bubble caps to be used per tray?

Related Mcqs:

1. For a given design of bubble cap, the number of bubble caps to be used per tray is set by the _________________?

   A. Allowable gas velocity through the slots
   B. Plate spacing
   C. Diameter of the column
   D. All A., B. and C.

2. In a distillation column, bubble caps are located on trays with a pitch of ______________ times the outside diameter of the caps?

   A. 1.3 to 2
   B. 1.6 to 2
   C. 2.5
   D. 1.5 to 3

3. In the allocated cap area, bubble caps are generally arranged on equilateral triangular pitch. Number of caps fixed on a plate is with a __________________?

   A. Clearance of 25-75 mm
   B. Cap pitch of 1.3-2 times the cap diameter
   C. Either A. or B.
   D. Neither A. nor B.

4. Bubble cap tray is the most commonly used tray in large distillation column, because______________?

   A. Of its flexibility and nearly constant efficiency under varying conditions of operation
   B. It incurs less pressure drop as compared to any other try designed for the same duty
   C. It eliminates the foaming and entrainment tendency during operation
   D. None of these

5. Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column ?

   A. Bubble cap trays though most expensive are the best in situations, where low vapour rates is to be handled and a positive liquid seal is essential at all flow rates
   B. Murphree efficiency of all the three trays are nearly equal, however the peak efficiency is generally higher for sieve and valve trays than the bubble cap
   C. Maintenance cost for valve and sieve trays are comparatively more than bubble cap tray due to their relatively complicated construction features
   D. Valve trays have the highest turn down ratio (i.e. the ratio of the highest to the lowest vapour flow rates) and thus provide the maximum flexible operating range

6. In actual operation of distillation column, the vapour is not distributed uniformly among the bubble caps, primarily because of the_______________?

   A. Liquid gradient on the tray
   B. Lower skirt clearance
   C. Lower static submergence
   D. Small downcomer liquid seal

7. In distillation columns, bubble caps are held in place over trays by ________________?

   A. Rivets
   B. A hold down bar
   C. Bolts
   D. Both B. and C.

8. The ideal size of round bubble caps to be used in industrial distillation column having a diameter of 3-6 metres is ________________ cms?

   A. 5
   B. 15
   C. 7.5
   D. 50

9. In a distillation column, minimum clearance to be maintained between the overflow weir and the last row of the bubble caps is ______________ cms?

   A. 2.5
   B. 7.5
   C. 15
   D. 20

10. Diameter of bubble caps used in high pressure columns is ______________ as compared to that used in identical vacuum columns?

    A. Less
    B. More
    C. Same
    D. Either A. or B.; no generalisation can be made