A. 0.1 to 0.3
B. 0.6 to 0.7
C. 0.85 to 0.95
D. 1.5 to 2
Related Mcqs:
- 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 - The operating velocity in the absorption tower is usually 40-50% of the flooding velocity. Packed absorption towers are normally designed for a pressure drop of about _________________ mm of water column per metre height of packing?
A. 1-5
B. 20-40
C. 100-150
D. 1000-1500 - 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 - In packed absorption tower, onset of flooding usually occurs at a pressure drop of about ______________ mm of water column per metre height of packing?
A. 25-50
B. 50-75
C. 200-250
D. 750-1000 - What is the value of ‘q’ for saturated vapor feed to a distillation column? (where q = fraction of the feed stream that is liquid ?
A. 0
B. 1
C. 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 - In a continuous distillation column, the optimum reflux ratio ranges from _______________ times the minimum reflux ratio?
A. 1.1 to 1.5
B. 1.6 to 2
C. 2.2 to 2.6
D. 2.7 to 3 - Multiple blade paddle agitator is used for mixing high viscosity liquids/paste in which the paddle diameter is commonly 0.8 times the tank diameter. However, the width of the blade is in the range of ______________ times the paddle diameter?
A. 0.1 to 0.25
B. 0.3 to 0.5
C. 0.5 to 0.6
D. 0.65 to 0.80 - In packed towers provided with pall rings liquid redistributors are positioned at heights of every 6 metres or 5-10 times the column diameter, whichever is less. Maximum size of the pall rings should not exceed _______________________ of the column diameter?
A. 1/10-1/15th
B. 1/5-1/10th
C. 1/20-1/30th
D. 1/2 to 1/4th - 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
