Rigorous Heat Exchanger - Column Attachment
Use this window to select an internal stream of a column as a feed to one side of the rigorous heat exchanger.
An internal stream of a distillation column can be heated or cooled by exchanging heat with a process stream using an attached heat exchanger. The internal stream can be linked with either side of the exchanger. The side of the exchanger depends on which Attach... button you pushed on the Feeds and Products Window to access this window.
If you chose Rating as the Calculation Type on the Rigorous Heat Exchanger Window, the duty of the heater-cooler will be determined by the column.
If you chose Fixed Duty or Tube Outlet Temperature or Shell Outlet Temperature as the Calculation Type on the Rigorous Heat Exchanger Window, the duty of the heater-cooler will be determined by the exchanger and cannot be varied in the column to meet a column specification.
Suggestion: Column convergence calculations are considerably enhanced when the column is allowed to calculate the exchanger duty.
Usage
Attach ... Side to Column
Check this option to confirm that a column internal stream is to be a feed to this side of the Rigorous Heat Exchanger.
Column
Select the column unit to which the heat exchanger is to be attached.
Attachment Type
Select the column attachment type. The choices available will depend on the existing attachments in the selected column. You cannot enter this data until the "Attach ... Side to Column" box is checked.
Condenser Select this to specify that this side of the exchanger is connected to the column condenser internal streams. If the condenser is modeled as a pumparound you should select the Pumparound attachment type instead.
Thermosiphon Reboiler or Reboiler Select either Thermosiphon Reboiler or Reboiler to specify that this side of the exchanger is connected to the column reboiler internal streams. Either Thermosiphon or Reboiler is displayed as the Attachment type based on the selected Reboiler type. For the Kettle reboiler, Reboiler is displayed as the attachment type and for the thermosiphon reboiler, Thermosiphon Reboiler is displayed as the attachment type. If the reboiler is modeled as a pumparound, select the Pumparound attachment type instead of Thermosiphon Reboiler or Reboiler.
If you have selected Thermosiphon Reboiler as the attachment type, you need to select one of the following 2 options to decide how iterative calculations have to be performed.
Iterative calculations with HTRI ON: Select this to update the circulation rate and duty specification with HTRI results. This is applicable when the HTRI runs in simulation mode.
Iterative calculation with HTRI OFF: Select this to update the column duty and circulation rate to HTRI in design and rating modes. This is applicable when the HTRI runs in design or rating mode.
Pumparound Select this to specify that this side of the exchanger is connected to a column pumparound. You must now identify which pumparound by selecting from the Heater/Cooler list for the chosen column.
Side Heater/Cooler Select this to specify that this side of the exchanger is connected to side heater or cooler streams. You must identify the Heater/Cooler and the source of the Heater/Cooler feed.
Phase and Rate of Side Heater/Cooler Feed
If a side heater or cooler has been selected, you must specify the following:
Side Heater/Cooler Feed is: the source of the feed stream.
Rate: the flowrate of the feed stream.
Set up Thermosiphon Reboiler piping
Click this button to specify the reboiler piping information.
Initialize HTRI Thermosiphon Reboiler piping
Select this to transfer the inlet and outlet piping data to HTRI.
The default length of the inlet and outlet pipe is 10 ft. Select either Diameter or Diameter Calculated by ρv2 to calculate the diameter of the inlet and outlet piping. ρ is the bulk stream density. For ρv2 known scenario, select Diameter Calculated by ρv2 to calculate the diameter. The default ρv2 value for inlet and outlet spec is 1000 lb-ft/sec2.
Simulation Mode Static Head
This allows you to specify the target static head in the HXRIG so that the HTRI heat exchanger can execute without the static head specified.
How to get to this window
The Column Attachment window is accessed by pushing the Attach... button on the Feeds and Products Window.
Rigorous Heat Exchanger - Technical Information