4 replies to this topic

[hysyshunter]

Hi, 

 

Currently i am designing a vacuum distillation column to separate glycerol from propylene glycol, however i need to be able to simulate and design how the vacuum is actually created in the column, through research and advice ive been informed that the vacuum is created through vacuum pumps and stem ejectors, and when i looked online i saw the primary use of oils and a fired heater to before the column. So im asking whether i need to incorporate oil and steam into my design or just vacuum pumps, because i am not cracking oil. 

 

Thanks  

[hysyshunter]

Sorry 've realised all i need to do is have a vacuum pump to create the vacuum, does anyone know if this is possible in HYSYS? i cant find any videos online

[Pilesar]

Typically, the model maker will set the column pressure to a value that is reasonably achievable. The vacuum system itself will be designed separately. To achieve the vacuum, you will condense the overhead vapor as much as possible with a heat exchanger and pull away any remaining uncondensed vapor with steam jets or vacuum pump. The condensing step is important because it reduces the amount of vapor sent to vacuum and also recovers valuable product.

[Eduard Osipov]

You can see some articles about vaccum systems modelling in HYSYS, Unisim and ChemCad.

 

https://www.mdpi.com/2305-7084/8/2/31

https://www.mdpi.com...-9717/9/11/1865

https://www.mdpi.com...-9717/8/11/1333

https://iopscience.i...3/6/062006/meta

https://link.springe...891-019-02020-7

[breizh]

Hi,

You have two separate problems:

  one is the simulation of your column operating under vacuum, just set the pressure which is one parameter of the simulation.

  For the vacuum different technologies are available, let say vacuum pump and ejectors.

  Vacuum pump could be dry vacuum pump or liquid ring vacuum pump. 

  For ejector, I believe we are talking steam ejector, it depends very much on how deep you need it. It will be single or multiple stages with         intermediate condensers.

Good luck

Breizh 

Attached Files

•  SIHI dry vacuum pump.pdf   591.57KB   18 downloads
•  liquid ring pump.pdf   1.77MB   10 downloads
•  Ejectors.pdf   196.07KB   11 downloads