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

Related Mcqs:

1. 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

2. 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

3. 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

4. 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.

5. 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.

6. 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.

7. The most common standard size of bubble caps used in industrial operation is___________________?

   A. 1″ dia cap with 0.5″ dia riser
   B. 6″ dia cap with 4″ dia riser
   C. 8″ dia cap with 1″ dia riser
   D. 4″ dia cap with 8″ dia riser

8. In actual operation of a bubble cap distillation tower, the ______________ at the bottom of the tower is more than that at the top of the tower?

   A. Molal flow rate of vapour
   B. Vapour molecular weight
   C. Pressure and temperature
   D. All A., B. and C.

9. Overall distillation column efficiency for most of the refinery columns can be given by (for μ = 0.07 – 1.4 cp and relative volatility < 4) (where ε = overall column efficiency, % μ = molal average viscosity of feed at average column temperature and pressure, cp Δp = pressure drop per tray, psi) ?

   A. η = 17 – 61.1 log μ
   B. η = 24.6 (Δp/μ)
   C. η = 1.66 – 0.25 log μ
   D. η = 0.25 log μ – 1.67

10. 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