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

Related Mcqs:

1. 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.

2. 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.

3. 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

4. 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

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. Bubble cap diameter used for the distillation column having diameter ranging from 1.5 to 4.5 metres is about ______________ mm?

   A. 10
   B. 50
   C. 100
   D. 200

7. In a shell and tube heat exchanger having square pitch, the shell side equivalent diameter is given by (where, P = pitch, d = outside diameter of the tube) ?

   A. 4(P2 – πd2/4)/πd
   B. (P2 – rd2/4)/rd
   C. 4P2/πd
   D. πd/4P2

8. Hole diameter of the sieve trays in the distillation column ranges from ______________ mm?

   A. 1 to3
   B. 4 to 8
   C. 3 to 12.5
   D. 12.5 to 18.5

9. 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

10. In case of bubble cap distillation column of diameter greater than 1.2 metres, the cap diameter is roughly about _______________ cms?

    A. 10
    B. 20
    C. 30
    D. 35