PROCESS EQUIPMENT AND PLANT DESIGN QUIZ

The design stress, which is more than the damaging stress, is the least unit stress that will render a member unfit for service before the end of its normal life. The design stress factor or factor of safety indicates the margin between design stress and the __________ stress.

None of these

Allowable

Working

Damaging

TRUE ANSWER : ?
YOUR ANSWER : ?

The force due to wind load acting on a tall vessel depends upon its

Outside diameter

All of these

Height

Shape

TRUE ANSWER : ?
YOUR ANSWER : ?

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 η = overall column efficiency, % μ = molal average viscosity of feed at average column temperature and pressure, cp Δp = pressure drop per tray, psi)

Η = 1.66 - 0.25 log μ

Η = 0.25 log μ - 1.67

Η = 17 - 61.1 log μ

Η = 24.6 (Δp/μ)

TRUE ANSWER : ?
YOUR ANSWER : ?

Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column.

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

Murphree efficiency of all the three trays are nearly equal, however the peak efficiency is generally higher for seive and valve trays than the bubble cap

Maintenance cost for valve and seive trays are comparatively more than bubble cap tray due to their relatively complicated construction features

Valve trays have the highest turn down ratio (i.e. the ratio of the highest to the lowest vapour flow rates) and thus provides the maximum flexible operating range

TRUE ANSWER : ?
YOUR ANSWER : ?