×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Cubic Plus Association

Cubic Plus Association

Cubic Plus Association

(OP)
I have been investigating applications of the Cubic Plus Association model
specifically the two variants available in Prode Properties,
one based on Soave Redlich Kwong and another on Peng Robinson.
As far as I can see these return similar results in VLE tests (mixtures of hydrocarbons+water), but I have a limited number of interaction coefficients for water-hydrocarbons and that could be a limit for my tests.
Prode includes a data regression procedure able to regress VLE/LLE/SLE data points but I have not the required experimental VLE data for hydrocarbons/water (of course I do not wish to estimate VLE with the UNIFAC option available in Properties),
my question is, does anyone know of free resources for experimental VLE data for water/hydrocarbons?
That would be very useful for all us working in natural gas industry.

RE: Cubic Plus Association

I am not aware of free resources including water-hydrocarbons VLE data, Dechema has a book (in Chemistry Data Series) but it's not free, perhaps a member can help...

However for CPA there are correlations to estimate kij values of water-hydrocarbons, one is
kij = -0.026 * C + 0.1915
where C is the carbon number
 

RE: Cubic Plus Association

I have collected some good data from GPA, you may consider that source.
I agree that Cubic Plus Association is very good for natural gas applications, it gives accurate results for hydrocarbons, water, glycols, alcohols, amines etc.
I think Prode does a good job including this model in the free version available in the web.

RE: Cubic Plus Association

I know only a few sources of reliable VLE data,
DECHEMA, DDB, (GPA)
unfortunately these are not free.
  

RE: Cubic Plus Association

There is also the Korea Thermophysical Properties Databank at http://www.cheric.org/kdb/

It seems that they do not generate VLE experimental data themselves the way DDB does, but they collect published data into a well indexed data base.  The menu does not work in Firefox (v12) on my computer but it is probably something that I have done wrone in the settings.  It works well in IE (v8).

Katmar Software - Engineering & Risk Analysis Software
http://katmarsoftware.com

"An undefined problem has an infinite number of solutions"

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources