7 replies to this topic

Dear All

My name is Muhammad Hamidihizami Bin Junis@Mohd Juraidi and I'm from Malaysia. I'm a final year chemical engineering's student in Institute of Technology PETRONAS. I'm a newbie in this forum.

Regarding using twister in Aspen HYSYS 2006, how to insert new unit operation twister in HYSYS 2006? I have a simulation project using HYSYS 2006 for my final year project which is study on NGL recovery using twister/swirl valve but have a problem to develop twister to the simulation. I know the philosophy of twister but don't know how to construct it using HYSYS 2006. I hope you can help me to solve this problem. All your kindness is much appreciated. Thank you

Regards

[Art Montemayor]

Muhammad:

Please do not make multiple postings of the same topic on our various forums. This goes against Forum policy. I deleted your other, identical posting on the student Forum.

Thank you.

Can anyone help me?

[Zauberberg]

According to the vendor, Twister performs somewhere in between the J-T valve (isenthalpic expansion) and Turboexpander (close to isentropic expansion). If you know what are the inlet and outlet parameters from the Twister unit, you can use a trick and split the feed stream in two parallel streams: one feeding the turboexpander, and the other one passing through a J-T valve, and then mixed/recombined afterwards.

[joerd]

If I remember right, you can model the Twister as an expander, with low efficiency (i.e. like Zauberberg said, between expander and JT valve), then a separator (probably with carryover) then a recompressor driven by the expander output. You can adjust performance of the Twister unit by playing with efficiency and carryover parameters.

[Zauberberg]

I can't remember as well what is the pressure recovery level in Twister tubes (if any). We had received a commercial offer for gas dew-pointing from Twister BV but that was almost 3 years ago and I can't remember the figures.

Attached Files

•  Twister.JPG   175.67KB   86 downloads

Thanks for the information. It really helpful. By the way, how we want to know that using combination of turbo-expander and jt valve will give almost the same result with twister itself?

For your information, I just get this pfd (see attachment) from internet. This pfd is made by genesis oil and gas consultant. From that simulation, twister and LTX are developed as one of unit operation in HYSYS. Just curious how they can made it? Any clue?

Attached Files

•  PFD Twister.doc   533KB   98 downloads

[joerd]

They programmed their own extension unit operation in Hysys. You can do that, but that's a whole other game, which requires in-depth knowledge of Hysys and programming skills. For your purpose, the method I described above should suffice, and once it comes to the design phase, Twister co. will happily work with you, I'm sure.
The LTX is like a cyclone separator, and again, someone went through the trouble of programming the unit operation as an extension to Hysys.

As far as modeling on your own, you should obtain information from Twister or elsewhere, to tune your efficiency and carryover to match their results. Then, you can extrapolate, to some extent.