Batch Distillation - Liquid Holdup
The condenser and tray liquid holdups are entered in this window. The holdup must be defined for every stage in the batch still.
Usage
Select the appropriate specification button to activate the desired mode of entry. The default choice is "Overall" with constant tray liquid holdup.
Overall Specification
The condenser and tray holdup are required. The tray holdup value is used for every tray in the column. Condenser holdup may be specified as "Bulk phase" holdup or "phase specific" quantities. Phase specific holdups are enabled only if "Calculated Condenser Phase" is set to the "Vapor-Liquid-Liquid" option. When the VLLE option is active for the condenser, both "Bulk phase" and "phase specific" options can be chosen. The condenser holdup value must be supplied; even when Individual Stage Specification for liquid holdups is provided.
Individual Stage Specification
Individual stage liquid holdups are supplied in tabular form. The stage value starts at 2, since the condenser is considered to be stage 1. The minimum data that must be provided are the holdups for the tray below the condenser and for the tray above the stillpot. Missing intermediate tray holdups are determined by linear interpolation. See Editing Tabular Data for more information about entering and editing tabular data.
The default basis for the holdup is "molar". The dimensional units for liquid holdup entries may be changed from the units shown on the screen by using the Unit of Measure Selection Window, which is displayed when the UOM button is pushed.
How to get to this window
The Batch Distillation - Liquid Holdup window is accessed by pressing the Liquid Holdup button on the Batch Distillation Main Window.
Related Topics