A. Split
B. Cross
C. Cascade
D. Reverse
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 - 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. - 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 - A perforated plate has holes of diameter dn arranged in a pitch ph. Each hole has a tube of I.D. dt passing through it. The ligament efficiency is given by_______________?
A. (ph – dh)/ph
B. (ph – dh . dt/2)/ph
C. (ph – dt)/ph
D. (ph – dh)/dh - An increase in the liquid resistance to interphase mass transfer and a resultant reduction in plate efficiency is caused by______________?
A. An increase in liquid viscosity
B. An increase in relative volatility for rectification columns
C. Decrease in gas solubility for absorbers
D. All A., B. and C. - Heat transfer co-efficient, hG(Kcal/hr.m2 .°C) and mass velocity of air, G (kg/hr.m2 ) for air flow parallel to the surface in case of constant drying rate in batch drying is related as hG = 0.0176G0.8. But when the flow of air perpendicular to the surface is encountered, this equation changes to ____________________?
A. hG = 1.004G0.37
B. 1.004G0.8
C. hG = 0.0176G0.37
D. 0.0176G1.37 - In case of plain carbon steel, butt welded joints are used for shell plate thickness ≤ _____________ cms?
A. 1.2
B. 0.5
C. 3.8
D. 6.8 - Tubes are fixed to the tube sheet (a thick circular metallic plate) by the method of tube rolling and brazing (non-removable) or ferrule connection (removable). Thickness of the tube, sheet is normally ____________ the outside diameter of the tube but in no case it should be less than 22 mm (7/8″)?
A. Half
B. Three fourth
C. Equal to
D. 1.5 times - For a cylindrical vessel of moderate height, the weld joint efficiency for joints parallel to the cylindrical axis is given as 1.0; while for joints along the girth (circumference) it is given as 0.8. In calculating the shell wall thickness using code formula for an internally pressurised cylindrical vessel, what value of weld joint efficiency should be used ?
A. 0.8
B. 0.9
C. 1.0
D. (0.8)0.5 - 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
