Single tray columns can only be created when they are first placed on the PFD. If you wish to change an existing column to a single tray column, you will need to delete the existing column and add a new single tray column.PRO/II allows the creation of Single Tray Columns, with or without a Reboiler. All of the distillation Column Algorithms support this type of column.
The special limitations that apply to Single Tray Columns are as follows:
Single tray columns can only be created when they are first placed on the PFD. If you wish to change an existing column to a single tray column, you will need to delete the existing column and add a new single tray column.
Once created, single tray columns cannot be resized. To change the number of trays, you will have to delete the existing single tray column and add a new column with the desired number of trays.
The single tray column does not support the use of a condenser and one will not be shown on the PFD.
Specifying the pressure drop for the column on an overall or per tray basis is not allowed. Instead, you specify the top tray (i.e. single tray) pressure.
Tray efficiencies are not allowed.
Thermosiphon reboilers and pumparounds are not allowed.
A controller is not allowed to perform feed-tray optimization for a single-tray column.