6 replies to this topic

[engeng]

Hello for ALL

When i do a simulation of a distillation column, how can I use the cold feed stream as a coolant to OVHD condenser within the same file in Aspen Hysys or I can not ?

Thank you in progress..

 

[Bobby Strain]

Use your imagination. But keep it simple. Don't use a heat exchanger. Use a heater and separate cooler. And duplicate streams.

 

Bobby

[engeng]

Thank you very much, I did a copy of streams and do it separatly. My question : is there a procedure to do it within the distillation column, in another word to make it like the actual  process flow diagram?

[Technical Bard]

You can use a heat exchanger to do this, but the solver may struggle with the solution.  You need to open the column subflowsheet and replace the condenser with a heat exchanger.  Then, you connect the feed stream and feed return stream to the column, and in the column subflowsheet connect those to the overhead condenser exchanger.

[engeng]

Thank you very much I will do this try and tell you.

[abhi_agrawa]

Engeng,

 

As mentioned by Bobby, if you model the tower and the condenser as separate blocks, then you create an unnecessary recycle loop. This can lead to convergence issues. I would suggest the following:

 

- Model the column including the condenser

- Create a pseudo-stream of vapor from Stage 2

- Use this pseudo-stream to model the exchanger

 

Hope this help,

Abhishek

[engeng]

Thank you very much for all