2 replies to this topic

[polipo]

Dear guys,

Frankly, I don't know how to correctly do the recycle in ASPEN PLUS.
Attached is my simulation in which the recycle can't be solved. I have no idea whether I do it right or wrong.
Can anyone guide me because the process isn't converged?
Which one should I adjust?

Thank you.

[che_bud]

Good Day Polipo,
Did you attach the file?

Based on my experience with recycles, you need to make the inlet and oulet conditions as close as possible for it to work. You would have to tweak the simulation to get this. You can add pumps/compressors and heat exchangers to get the required pressure and temperatures but I only do this to get the simulation to converge and then try to tweak it to remove these extra equipment. I am not sure how other people do it.

I hope this helps.

che_bud

[leon_aurel]

When we have a recycle stream in our simulation, aspen will do the simulation to converge a stream.So, first you should make an estimation of this stream (T, P, flow). Then try to run your simulation.
If everything go well, you just need to reestimate your estimation until converge.

Maybe while the simulation is running there is some problems occured. You can reinitialize your simulation and running it again step by step using "step" button, this way you can know in which part of your simulation
the problem is occured and do some correction to your setting.