How to use Recycle in Hysys or Unisim
Thread Content
How is Recycle used in Hysys or Unisim? The reflux coming from the side line of the tower returns to the tower after heat exchange; a Recycle stream is required for this process. Please advise experts
For Recycle, there is one input and one output; the output value must first be assigned a initial value to control the convergence accuracy. The reflux coming from the side line of the tower can be returned to the tower via heat exchange and processed as a pump-driven circulation, which makes convergence easier and eliminates the need for recycling; if a side line extraction is required, another side line extraction can be arranged on the same tray.
Okay, thanks to the person above; I’ll give it a try
Okay, thanks to the person above; I’ll give it a try
Reply to 2# *ayh126: If only the pump is used, to make the column converge, information on the feed is required; that is, information on the reflux is needed in order to carry out the calculations. Without Recycle, can we assume the feedback information and proceed with the calculations directly?
For pump circulation, only 2 out of flow rate, temperature, and heat need to be specified； Without recycling, the reflux is equivalent to a feed stream; it can be calculated, but it does not correspond to the actual column operation.
Reply to 6# *ayh126: I see. It seems that Recycle is indeed the more accurate option