3-phase separator

Hi there. I am trying to simulate a 3-phase separator using the separator unit to separate an oil stream into gas, hydrocarbons and water. When I put the data operations (using T-P flash for feed stream) the separator only separates it into two streams instead of three. I have simulated this case in HYSYS where it works fine to separate the three phases Any help on this?


Feed= 20 °C / 200 kPa / 100 kgmol/h. components in molar fraction:

Methane: 0,10 / Ethane: 0,03 / Propane: 0,04 / i-Butane: 0,08 / n-Butane: 0,10 / i-Pentane: 0,12 / n-Pentane: 0,13 / Water:0,40

I tried even putting a valve with a pressure drop of 10 psi to altered the vapor fraction.

DWSIM 14-05-20, 3:09 a.m. Danita

Please change the flash algorithm of the feed stream to Nested Loops (VLLE).

To do this, go to Settings. Under the Thermodynamics tab, double click on Nested Loops (VLLE) under Available Flash Algorithms to add it to Added Flash Algorithms.

Once added, go back to the Flowsheet. Click on the Feed Stream. In the Property Editor Window, click on the drop-down against Flash Algorithm and select Nested Loops (VLLE). Once done, click on Simulate. You will see the feed stream getting separated into three streams. You need not use any additional valve for the separation.

14-05-20, 12:23 p.m. Priyam_Nayak


Many thanks for the guidance, I also review the User Guide to understand better the options of the Flash Algorithms and actually the one that worked is the Inside-Out VLLE since it this is the one recommended for petroleum systems. Cheers!

14-05-20, 4:51 p.m. Danita

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