Batch Distillation - Initial Pressure Profile
The initial batch distillation pressure profile is provided using this window. It is used in all policy segments that do not define their own pressure profiles. The pressure must be defined for every stage in the unit.
Usage
Select the appropriate Pressure Specification Mode button to activate the desired mode of pressure entry. The default choice is "Overall" with the column at constant pressure.
Overall Specification
The condenser pressure and one pressure drop entry are required. The top tray pressure is optional. The pressure drop is designated by selecting the appropriate Pressure Drop button to indicate the pressure difference per stage or over the whole column or the stillpot pressure. The default pressure drop is zero per stage.
When the pressure drop is given for the column, or the stillpot pressure is specified, the pressures for intermediate stages are determined using linear interpolation.
Individual Stage Specification
Individual stage pressures are supplied in tabular form. The minimum data that may be provided are the pressures for the condenser and stillpot. Missing stage pressures are determined by linear interpolation. See Editing Tabular Data for more information on the entry and editing of tabular data.
The dimensional units for pressure 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 - Pressure Profile window is accessed by pressing the Pressure Profile button on the Batch Distillation Main Window.
Tray pressures can be supplied via radio buttons in this dialog box on an overall or tray-by-tray basis. For the overall mode, supply the
condenser pressure as well as one of the following:
Pressure drop per tray (defaults to 0.0 psi).
Column pressure drop (defaults to 0.0 psi).
Stillpot pressure.
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