Process Equipment and Plant Design
A cylinderical pressure vessel of volume 6 πm³ has to be designed to withstand a maximum internal pressure of 10 atm. The allowable design stress of the material is 125N/mm² and corrosion allowance is 2 mm. The thickness of the vessel for a length/diameter ratio of 3 will be close to
Maintenance cost for valve and seive trays are comparatively more than bubble cap tray due to their relatively complicated construction features
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
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
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