Process Equipment and Plant Design
An increase in the liquid resistance to interphase mass transfer and a resultant reduction in plate efficiency is caused by
All of these
An increase in liquid viscosity
An increase in relatived volatility for rectification columns
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
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