2 replies to this topic

[Ingridekle]

Hi,

 

I have some problems regarding my simulation in HYSYS, which maybe somebody can help me with.

 

I am designing a Scrub Column in HYSYS which separates C1/C2 (to become LNG) and C3+. The column is designed as a reboiled absorber without reflux. (use of non reflux column is done Intenionally)  Furthermore, I have several cases, with various feed gas compositions. This is to assess the feed flow flexibility in the column.

 

I want to compare results based on liquid and gas flows in the column. As I understand it, a to high vapour flow can create flooding and a to low vapour flow can create weeping/dumping.

 

For all my cases, the column converges. But can flooding or weeping still occur? I have tried do find data on this in HYSYS, but there seem to be no utilities available to register this. There are such a thing as FRI Tray Rating Utilities, but I can not access this. 

 

Is there another way to find out wether my vapour flows/ liquid flows are outside operating area?

 

I appreciate all response, and if there are some confusion in my question I will gladly try to describe better:)

 

[PingPong]

While you are simulating a new column you need not worry about entrainment or weeping, as that is only to obtain the heat and material balance(s).

 

Later, when you actually size the column/trays/packing using dedicated (vendor) software for column design (not some simulator), based on the simulated vapor and liquid loadings from the final simulation(s), then entrainment and weeping are determining factors. But the software will warn you for that, if it could occur.

[curious_cat]

As @Pingpong says, when you get to the column hydraulics stage try the KGTower software by Koch Glitsch or Sulcol by Sulzer. Both allow you to determine your weep / flood limits etc.