The minimum plate spacing in most of the petroleum refinery distillation columns (of dia > 3 ft) is normally _____________ inches?

Related Mcqs:

1. The minimum tray spacing in distillation column of diameter less than 3 ft is normally _____________ inches?

   A. 6
   B. 18
   C. 24
   D. 34

2. In the design of a paddle agitator, the ratio (paddle dia/tank dia) is normally taken as___________________?

   A. 0.1
   B. 0.8
   C. 0.25
   D. 0.5

3. The ratio, (propeller agitator dia/tank dia) is normally taken as____________________?

   A. 0.15-030
   B. 0.5-0.65
   C. 0.75-0.85
   D. 0.60-0.90

4. 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

5. Frame thickness in the plate and frame filter press is normally in the range of ______________ inches?

   A. 0.25 to 4
   B. 0.25 to 8
   C. 1 to 5
   D. 1 to 12

6. A high vapour velocity is required for high plate efficiency in a sieve plate column. The satisfactory value of operating vapor velocity for design purpose in sieve plate column is about _______________ percent of the flooding velocity?

   A. 45
   B. 60
   C. 80
   D. 95

7. Height equivalent to a theoretical plate (HETP) is the height of packing that will give the same separation as one theoretical plate in gas-liquid mass transfer operations like distillation, absorption/stripping and humidification/dehumidification. HETP which is experimentally determined, depends upon the_______________?

   A. Flow rates of each fluid
   B. Type and size of packing
   C. Concentration of each fluid
   D. All A, B. & C.

8. To avoid the tearing off the plate of an edge, the margin (i.e., the minimum distance from the centre of the rivet hole to the nearest edge of the plate) should be equal to ____________________?

   A. 0.5 d
   B. d
   C. 1.5 d
   D. 2.5 d

9. 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

10. For a cylindrical shell, (subject to the thickness of uppermost course being more than the minimum for dia of the tank in question), the thickness of the courses of shell_________________?

    A. Decreases upwards
    B. Increases upwards
    C. Remains same throughout
    D. May decrease or increase upwards depending upon whether vacuum or positive pressure
    would be maintained inside the shell