HYSYS Operations Guide

2-184 Column-Specific Operations
Efficiencies Page
As with steady state, you can specify tray efficiencies for
columns in dynamics. However, you can only specify the overall
tray efficiency; component tray efficiencies are only available in
steady state.
Figure 2.140
Pressure Drop Page
The Pressure Drop page displays the information associated with
the pressure drops (or pressures) across the tray section.
The Pressure Drop page uses the same calculation in the
Tray Sizing utility to calculate the pressure drop for the tray
sections when the column is running. In other words, using
the traffics and geometries to determine what the pressure
drop is.
Selecting the Rating Enabled checkbox turns on the pressure
drop calculations as part of the column solution.
The tray sizing utility calculates a pressure drop across each
tray, you need to fix one end of the column (top or bottom),
allowing the other trays to float with the calculations. You can
select which end of the column to be fixed by selecting the
appropriate radio button in the Fix Tray group.
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