Jump to content



Featured Articles

Check out the latest featured articles.

File Library

Check out the latest downloads available in the File Library.

New Article

Product Viscosity vs. Shear

Featured File

Vertical Tank Selection

New Blog Entry

Low Flow in Pipes- posted in Ankur's blog

0

Cpa Cubic Plus Association Packages

cpa cubic plus association prode

3 replies to this topic
Share this topic:
| More

#1 neriet

neriet

    Junior Member

  • Members
  • 16 posts

Posted 16 January 2018 - 08:28 AM

I have been suggested to select CPA Cubic Plus Association for a water-methanol and water-ethanol separations (water, alcohols plus several other components),
my copy of Prode Properties software (Base version) includes three CPA packages, PRXCPA(VDW) , PRXCPA-NRTL(P-HV) and PRXCPA-NRTL(P-LVM),
are these CPA equivalent ?
Also, my version of Prode doesn't include the CPA package for enthalpy, which package do you recommend (for water-alcohols) ?
Thanks for help.



#2 PaoloPemi

PaoloPemi

    Gold Member

  • Members
  • 463 posts

Posted 16 January 2018 - 09:27 AM

see also this thread,

https://www.cheresou...ation-in-prode/

 

Prode Properties Base has 4 packages based on CPA (one derived from Soave-RK and three from Peng Robinson),

two with VdW mixing rules and two with complex (modified Huron Vidal and modified LCVM) mixing rules,

the models with complex mixing rules are more flexible (i.e. NRTL with temperature dependent parameters) but a bit slower,

I would prefer PRXCPA-NRTL because of additional flexibility ,  P-HV means modified Huron Vidal while P-LCVM the Linear Combination of Vidal and Michelsen rules,

for enthalpy you can select the base model with complex mixing rules (i.e. PRX-NRTL (P-HV) or (P-LCVM)

another possibility would the MBWR or similar models which however are available in extended versions, only.



#3 neriet

neriet

    Junior Member

  • Members
  • 16 posts

Posted 16 January 2018 - 11:18 AM

thanks,

in your opinion, do the existing BIPs provide good accuracy or should I run the VLE/LLE data-regression utility ?



#4 PaoloPemi

PaoloPemi

    Gold Member

  • Members
  • 463 posts

Posted 16 January 2018 - 12:03 PM

that depends from operating conditions (in your case),

you can inspect the range of values in data regression, these values are stored (with average error) in Prode Properties, BIPs database

xuSFXJ.jpg

in this case (water-methanol) error is low even if NRTL doesn't include temperature dependences (U12-T and U21-T are 0),

the association terms in CPA provide the required interaction parameters,

 

anyway, if you have access to VLE data points you can calculate the BIPs (with the included VLE/LLE/SLE data regression utility)


Edited by PaoloPemi, 16 January 2018 - 12:04 PM.





Similar Topics