#  > Petroleum Industry Zone >  > Engineering Spreadsheets & Presentations >  >  >  Excel library for process calc's including distillation

## carlo.stenali

Prode "www.prode.com" has a thermodynamic library which works with Excel and does a lot of things, there is a free version, some Excel examples are provided as :
Properties of pure fluids and mixtures
Multiphase equilibria
Phase envelope
Dew, bubble point, critical points, cricondentherm, cricondenbar
Distillation column


and more...
hoping this helpsSee More: Excel library for process calc's including distillation

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## crcr

very useful

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## lviv

It's great!thanks very much!

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## hans23

REALLY GREAT EXCEL TOOL FOR PROCESS CALC'S !!!
Thank you,
Hans

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## rense

propiedades de los gases, liquidos y solidos, equilibrio liquido-vapor, vapor-liquido-liquido, destilacion ...

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## torek

fantastic process library !!
Thank you

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## mabuk

very nice!!!

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## chem4253

fantastic software !!!
Thank you

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## chemnguyents

good materials

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## Almart

Great software
thank you

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## crat

really great library !!!
Thank you !!!

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## tmander

very useful,
thank you !

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## tinom

great software !
Has anyone compared the phase envelope in Excel with other simulators ?


Looks very good to me !See More: Excel library for process calc's including distillation

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## masarett

seems very interesting software !
Thank you

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## asanter

I do my calc's in Excel, this is good software

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## carlo.stenali

>Has anyone compared the phase envelope in Excel with other simulators ?
>Looks very good to me ! 

yes, I did and found a good agreement, it's good software

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## abarre

very interesting software for Excel's users !

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## mpat

the free version has a limited number of chemicals but there are the most common hydrocarbons C1-C13 plus water, ammonia, toluene etc.
Very good software.

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## cmarc

thank you, nice sofftware

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## dbert

has anyone experience with the column model in this library?
I need to solve distillation columns (hydrocarbons)  with two (or more) feeds.
Comments appreciated.

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## mpat

"has anyone experience with the column model in this library? I need to solve distillation columns (hydrocarbons) with two (or more) feeds.Comments appreciated."

dbert,
I have not a large experience but I have spent several hours with free version, the distillation column works well (I have a couple of examples with two feeds) and convergence is reliable even with difficult spec's. 
In my opinion the biggest limit in free version is that you can't define pump arounds, they are supported only in commercial versions, by the way chemsep lite (another free software) does support pump arounds but convergence could be a little problematic.
Apart from this they are both very good software.

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## dbert

thanks for the comments,
I have no pump arounds but multiple feeds and one side drawn, and Peng Robinson should work well in my case.

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## abarre

I have a couple of comments, too.
The Excel page included in distribution files doesn't "show" all the features, the method DCOL in library does allow additional specififications as dH on each stage, according the documentation it solves also VLLE and LLE.
I don't know which are the limits, as max number of stages etc. however according my tests it can solve a 100 stages column without much troubles.
I have been in contact with Prode to get some assistance and I got answers even I was not interested to purchase the licence.

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## cbadia

gracias !!

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## mderra

nice software !

See More: Excel library for process calc's including distillation

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## dserra

thank you,
does this software calculate liquid-liquid equilibria ?

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## carlo.stenali

yes, liquid liquid as well as vapor liquid liquid and true multiphase are supported, 
see for example
"http://www.prode.com/en/multiphase.htm"
vapor-liquid-solid is a bit limited in free version but you can contact the author to get a more featured version.

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## mderra

thank you,
I did a try to liquid liquid equilibria regression tool and it seems to work fine,
nice tool.

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## abarre

thank you !!

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## cmarc

thank you for the comments concerning use and features !

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## rense

thanks!

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## mpat

thnx for the comments

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## tinom

thank you !!!!!

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## mkhurram79

thank u very much for this nice post

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## tmander

I did several tests comparing against our $$$ simulator and getting equivalent results,
it's amazing to see how Excel can be useful !

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## aperra

Es un muy buen library para Excel,
gracias !!!

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## rense

hola Alfonso,


VBA puede ser utilizado para programar pequenas aplicaciones dentro de un documento Excel, el sistema con columna de destilacion continua tiene una serie de macros.See More: Excel library for process calc's including distillation

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## Almart

does anyone have experience with pipeline module in Prode Properties ? 
According the operating manual it should include Beggs & Brill multiphase model,
I am interested for simulating a short (100 mt) line,
thanks.

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## mpat

(AFAIK) pipeline it's not included in (free) base version,
however I was able to compare results (you may contact prode to get a free calc) against those of our reference software and the agreement is good, we are considering to purchase a licence (base version), I will say more once I get the complete version.

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## Almart

thank you,
I'll contact Prode as suggested

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## torek

good comments,
thanks to all contributors !

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## pdas

very nice sofware for phase envelope and distillation , works better than our process simulator !
Free version has a limited database so I would recommend mainly to students.

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## mderra

have you tested Properties with Excel 2010 ?
I plan to update my Excel but not sure how many applications will work with the 2010 version (I read several caution advices about updating from 2007 to 2010),
thank you.

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## carlo.stenali

mderra,
it should work in Excel 2010, 
I have tested with Excel 2003 and Excel 2007, I have Excel 2010 in my portable but still running previous versions as I have not had time for moving all my Excel applications.
Yes, I have read of some issues when running Excel 2003 works in 2010 but it should concern mainly the different protection system in 2010.

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## mderra

thank you Carlo,
possibly I am in the same position as you, 
still not moving to Excel 2010 as I do not like problems :-)

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## pdas

'm now running Prode Properties in Excel 2010, 
as fas as I have seen it works as in 2007

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## mderra

thank's pdas, 
a useful information

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## matrenel

does this Excel application calculate critical points of natural gas ?

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## pdas

Properties is able to calculate the true critical points of multicomponent mixtures, I do that from the Excel application page distributed with the software, it plots the phase envelope with critical points,  cricondenbar and cricondentherm.

See More: Excel library for process calc's including distillation

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## matrenel

I have a C1-C9 + N2, CO2  mixture and I wish to calculate phase envelope with critical point, 
how reliable is this sofware ?
have you compared resuls against oter simulators ?

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## carlo.stenali

I would suggest that you read this page
"http://www.prode.com/en/phaseenvelope.htm"
then if you have specific questions post here,
Carlo

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## matrenel

thanks

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## rbru

very, very nice,
thank you !

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## cmarc

May I ask for a little help with multiphase vapor-liquid-liquid ?
I get vapor +  two liquid phases where another software says there is a vapor and one liquid phase, I would be interested in a procedure for testing the stability of the mixture.

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## carlo.stenali

cmarc,
Properties does have methods for calculating fugacites and derivatives vs. composition, pressure, temperature, see the manual , page 60

"http://www.prode.com/docs/pppman.pdf"

here there is a copy and paste

integer res = StrFv(integer stream,integer state,double t ,double p, double *w,double *fg)
Given a predefined stream the required state (vapor, liquid, solid) ) and operating conditions returns the vector of fugacities (Pa)
integer res = StrFvd(integer stream,integer state,double t ,double p, double *w,double *fg, double *dfgt,
double *dfgp, double **dfgw)
Given a predefined stream the required state (vapor, liquid, solid) ) and operating conditions returns the vector of fugacities (Pa)
and related derivatives vs. temperature (K), pressure (Pa), composition (note : derivatives vs. composition as matrix [n][m])
integer res = StrFvdv(integer stream,integer state,double t ,double p, double *w,double *fg, double *dfgt,
double *dfgp, double *dfgw)
Given a predefined stream the required state (vapor, liquid, solid) ) and operating conditions returns the vector of fugacities (Pa)
and related derivatives vs. temperature (K), pressure (Pa), composition (note : derivatives vs. composition as vector [n*m])
integer res = StrlnFv(integer stream,integer state,double t ,double p, double *w,double *lnfg)
Given a predefined stream the required state (vapor, liquid, solid) ) and operating conditions returns the vector of ln fugacities
integer res = StrlnFvd(integer stream,integer state,double t ,double p, double *w,double *lnfg, double
*dlnfgt, double *dlnfgp, double **dlnfgw)
Given a predefined stream the required state (vapor, liquid, solid) ) and operating conditions returns the vector of ln fugacities
and related derivatives vs. temperature (K), pressure (Pa), composition (note : derivatives vs. composition as matrix [n][m])
integer res = StrlnFvdv(integer stream,integer state,double t ,double p, double *w,double *lnfg, double
*dlnfgt, double *dlnfgp, double **dlnfgw)
Given a predefined stream the required state (vapor, liquid, solid) ) and operating conditions returns the vector of ln fugacities
and related derivatives vs. temperature (K), pressure (Pa), composition (note : derivatives vs. composition as vector [n*m])

with these methods you can use the tngent plane analysis to validate the stability of a system,
do you know this procedure  ? If not I can suggest some good textbooks.

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## cmarc

I remember Baker's work, do you suggest to calculate the tangent plane distance from compositions & fugacities ? 
That could be done in Properties, unfortunately I can't with a different software.

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## tinom

to validate a condition you must find a way to calculate Gibbs energy (and compare with a different state)

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## cmarc

thanks carlo.stenali & Tinom,
another question, 
how can I set BIPs for UNIQUAC, NRTL etc. ?

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## carlo.stenali

in Properties you can set BIPs via Stream Editor or programmatically (there are more than 300 methods/macros exported which you can use) 
Properties has a database for Kij, Aij, Gij etc. and procedures to regress VLE/LLE data.

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## cmarc

carlo.stenali,
I wish to define compositions and BIPs from Excel VBA, which is the correct way ?
Thank you.

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## carlo.stenali

Properties is very flexible and there are different ways to define by code compositions, BIPs etc.


Here there is the code from "Prode.com" site :

; define a stream
Stream = 1

; Initialize the stream
initS(Stream)
; define the model for gas phase fugacity
setMFg(Stream,SRK_MODEL,GAS_PHASE)
; and liquid phase
setMFg(Stream,,SRK_MODEL,LIQ_PHASE)
; set the list of components
putCC(Stream,1,H2S)
putCC(Stream,2,METHANE)
putCC(Stream,3,CO2)
; set molar compositions
putZ(Stream,1,0.15)
putZ(Stream,2,0.7)
putZ(Stream,3,0.15)
; row 1, Kij components 3-2
putCi(Stream,1,3)
putCj(Stream,1,2)
putMod(Stream,1,SRK_MODEL)
putKji(Stream,1,0.097)
; row 2, Kij components 3-1
putCi(Stream,2,3)
putCj(Stream,2,1)
putMod(Stream,2,SRK_MODEL)
putKji(Stream,2,0.102)
; row 3, Kij components 1-2
putCi(Stream,3,1)
putCj(Stream,3,2)
putMod(Stream,3,SRK_MODEL)
putKji(Stream,3,0.085)
; finally save data
setS(Stream)

; as alternative you can utilize the method loadSB to looad binery intercation parameters from database

loadSB(Stream)


if you wish to change a composition just use this code

; set new molar compositions
putZ(Stream,1,0.3)
putZ(Stream,2,0.3)
putZ(Stream,3,0.4)
; save data
setS(Stream)

and so on...See More: Excel library for process calc's including distillation

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## cmarc

thanks

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## tinom

cmarc, you may contact Prode, in my case the author has been very helpful.

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## cmarc

thanks tinom,
actually I am not a registered user, just evaluating the software.

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## tmander

I see an active thread on the subject,
has someone verified the different operating between minimum Gibbs energy and isothermal compressibility criteria in determining the state of a mixture ?

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## carlo.stenali

in dense phase region (near critical point) with a EOS as Soave Redlich Kwong or Peng-Robinson you can obtain only one root, that corresponding to gas or liquid state, with one solution you can't apply Gibbs Minimum Energy criteria, since isothermal compressibility has different values in gas and liquid state you can use that property to define the state.
As far as I can test Properties is quite reliable in selecting the proper solution even near a critical point.

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## tadole20

F-Secure  found   "Gen:Malware.Heur.Jq0@bCdrXlhi"

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## carlo.stenali

tadole20, 
as far as I know there are several hundred users of this software... 
if you have specific technical questions I would suggest to contact the author and get assistance, differently your comment here would appear quite strange...
Once I reported a problem to Aspen, just to find that it was my computer...

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## tmander

Carlo.Stenali, I am interesetd to know the criteria used by Properties for selecting the phase in single phase regions, convergence issues are common problems with these tools, for example our simulator in critical region can report two phases in equilibria even outside the phase envelope, there is a note in the operating manual concerning thi s issue.

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## carlo.stenali

if you are interested in details, my suggestion is to contact the author.
However having spent some time with Properties I can say that isothermal flash converges quite reliably in critical region (this as result of some tests against well now simulators), there are different versions of the software and i was informed that all do use local Newton + global solver.
I can add that in my tests I haven't found problems with Gibbs Minimum Energy criteria (the default).

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## mderra

I can confirm that Properties works very well with hydrocarbons, I have not tested with other mixtures.
I have a question, which is the maximum number of streams ? My copy accepts only up to 50 streams.

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## aragorn

Thanks

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## carlo.stenali

Mderra,
Properties base release 1.18 can manage up to 500 streams, 


you can redefine the maximum number of streams from Prode Properties Editor, go in Config and then Settings, the first row is the "Max number of streams", this field accepts values up to 500 streams, if you wish to set this value as default save into the archive with the name def.ppp, note that you must exit and restart the software to load the new configuration.See More: Excel library for process calc's including distillation

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## mderra

thanks,
I need to define about 100 streams for a simulation of a gas plant which I hope to solve from Excel, an interesting exercise anyway.

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## cmarc

mderra,
according my experience the main problem when simulating a plant in in Excel is the solution of recycles, Properties can solve single equipements as distillation columns, separators, pipelines etc. but with recycles you must find a way to iterate toward the desired solution, Excel has a general purpose minimizer but unfortunately it is quite limited.

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## mderra

thanks cmarc,
that could be difficult to solve, fortunately I have only two parameters to adjust and and I do that with VBA code, very slow but working.

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## dbert

is anyone running Properties from Matlab ? 
According Matlab site (see MATLAB Interface to Shared Libraries) it should be able to call external Dlls as Properties.
Help will be appreciated.

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## hans23

dbert,
my copy of Matlab is old but I was able to access methods in Properties, the library adopts the C calling convenction required by Matlab, you need to define in Matlab the passing parameters for each method, not difficult as these are those in ppp.h header, don't know if Prode provides Matlab examples.

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## dbert

thanks, I am not a programmer so it was not easy, however now I can call several methods in Properties from Matlab. 
For my work I need to calculate some alcohol and water equilibria, Prode Properties has a VLE/LLE data regression procedure but I have not access to experimental data ,can someone help with VLE data for water-ethanol, water-metrhanol etc. ?

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## carlo.stenali

dbert, in my library (from Dechema) I found this :

VLE methanol-water 760 mmHg, third column temperature in degrees Celsius
  0.000000  0.000000   100.000
  0.050000  0.278000    92.400
  0.100000  0.425000    87.700
  0.200000  0.602000    81.700
  0.300000  0.692000    78.000
  0.400000  0.752000    75.400
  0.500000  0.798000    73.200
  0.600000  0.838000    71.200
  0.700000  0.878000    69.400
  0.800000  0.915000    67.700
  0.900000  0.960000    66.000
  1.000000  1.000000    64.600

VLE ethanol-water 760 mmHg, third column temperature in degrees Celsius
  0.000000  0.000000   100.000
  0.050000  0.278000    92.400
  0.100000  0.425000    87.700
  0.200000  0.602000    81.700
  0.300000  0.692000    78.000
  0.400000  0.752000    75.400
  0.500000  0.798000    73.200
  0.600000  0.838000    71.200
  0.700000  0.878000    69.400
  0.800000  0.915000    67.700

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## carlo.stenali

it seems there was an error with copy and paste...
VLE methanol-water 760 mmHg, third column temperature in degrees Celsius
  0.000000  0.000000   100.000
  0.050000  0.278000    92.400
  0.100000  0.425000    87.700
  0.200000  0.602000    81.700
  0.300000  0.692000    78.000
  0.400000  0.752000    75.400
  0.500000  0.798000    73.200
  0.600000  0.838000    71.200
  0.700000  0.878000    69.400
  0.800000  0.915000    67.700
  0.900000  0.960000    66.000
  1.000000  1.000000    64.600

VLE ethanol-water 760 mmHg, third column temperature in degrees Celsius
  0.018000  0.179000    95.500
  0.054000  0.337500    90.600
  0.124000  0.470000    85.400
  0.176000  0.514000    83.700
  0.230000  0.542000    82.750
  0.288000  0.570000    82.000
  0.385000  0.612000    81.000
  0.440000  0.633000    80.500
  0.514000  0.657000    79.800
  0.673000  0.735000    78.900
  0.840000  0.850000    78.260

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## dbert

thanks,
by chance do you have access to water-2 propanol VLE data ?

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## carlo.stenali

I have several data sets for 2-propanol water equilibria,

see "http://www.prode.com/docs/pppman.pdf" for the data regression procedure in Properties,

VLE 2-propanol-water 760 mmHg, third column temperature in degrees Celsius
  0.013000  0.231000    92.200
  0.018000  0.245000    91.000
  0.033000  0.339000    87.800
  0.045000  0.399000    86.200
  0.044000  0.409000    86.000
  0.046000  0.389000    85.800
  0.053000  0.415000    85.500
  0.126000  0.505000    82.800
  0.241000  0.545000    81.600
  0.321000  0.547000    81.000
  0.523000  0.596000    80.500
  0.581000  0.629000    80.300
  0.844000  0.810000    80.500
  0.860000  0.810000    80.600
  0.926000  0.873000    81.200

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## dbert

thanks Carlo,
may I ask for1-Hexanol-water ?
:-)

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## carlo.stenali

dbert, I am travelling and without library access,  however as a rough estimate you may consider a solubility 1-Hexanol in water of about  5-6 g/L at 25 C ...

See More: Excel library for process calc's including distillation

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## superandy

Attached a file txt containing equilibrium data for the system 1-hexanol/water from hysys.

Regards
Superandy

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## dbert

thanks Superandy,
do you know if that comes from regressing Wilson parameters to experimental data or to estimated values (i.e. VLE by UNIFAC etc.) ?
I say this as I calculated Wilson parameters for 1-Hexanol/Water with UNIFAC VLE and  I got parameters which seem to fit your data, but that could be a coincidence.

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## superandy

They are estimated data using UNIFAC!

To find experimental data you must try Dechema databank and you must pay for them.

Regards
Superandy

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## dbert

thanks superandy, I appreciate your help,
UNIFAC is my standard when experimental data are not available, however in this specific case I have some doubts about predicted TPXY

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## cmarc

Properties has a decent procedure for VLE/LLE data regression, it does offer the possibility to regress from UNIFAC as suggested by superandy but UNIFAC predictions can be unreliable, actually I am calculating VLE for 2-butanol water, can someone give experimantal data to compare ?

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## carlo.stenali

dbert,
1-Hexanol in water has limited miscibility, you should look for LLE instead.

cmarc, I have several data points,

VLE 2-Butanol Water 760 mmHg, third column temperature in degrees Celsius
0.009500  0.116000    92.700
0.016600  0.214000    91.000
0.021000  0.303000    89.700
0.025700  0.343000    89.500
0.034500  0.387000    88.200
0.043000  0.385000    88.000
0.046800  0.386000    87.900
0.501000  0.452000    88.700
0.519000  0.463000    88.700
0.563000  0.470000    89.000
0.607000  0.493000    89.700
0.711000  0.520000    89.800
0.816000  0.624000    92.100
0.901000  0.731000    94.200
0.960000  0.801000    95.800
0.984000  0.898000    97.700
0.996000  0.952000    98.400

see "http://www.prode.com/docs/pppman.pdf" for the data regression procedure in Properties,

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## dbert

thanks carlo.stenali,
really I need to calculate VLE but I do not know if UNIFAC works reliably in this case.

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## cmarc

thanks Carlo. I am doing some VLe calc which (perhaps) would require complex mixing rules,  which options do you recommend to set in Properties ?

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## carlo.stenali

at low pressures NRTL should be Ok, my version adds Huron-Vidal & Wong-Sandler , these should be a bit better for a range of pressures

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## cmarc

thanks, by chance can you help with  Benzyl Alcohol-Water VLE data ?

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## carlo.stenali

hi cmarc, 
I have some water-benzyl alcohol VLE points at 760 mmHg,

first column X(1)
second column Y(1)
third column temperature in degrees Celsius
0.050000  0.840000   148.200
0.100000  0.929000   129.600
0.150000  0.956000   120.900
0.200000  0.968000   115.000
0.250000  0.976000   110.600
0.300000  0.981000   107.100
0.400000  0.986000   102.800
0.500000  0.989000    99.000

if you need frequently VLE data perhaps you may consider dechema which provides also data regression parametrs, however these parameters were limited (I don't know last versions) to some standard activity models,  I have found Properties useful for VLE/LLE data regression with nonstandard models, see "http://www.prode.com" for information.

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## cmarc

thanks Carlo,


they are really good for my actual projectSee More: Excel library for process calc's including distillation

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## tmander

can someone explain the different options for phase envelope calc's in Properties ? I am familiar with the minimum Gibbs Energy criteria which is the standard for process simulators but I do not understand validate EOS roots according state.

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## carlo.stenali

tmander, my copy has three different options 

1) standard
2) select EOS root for minimum Gibbs Energy
3) Validate EOS root according state

the usual way is to select the EOS root for minimum Gibbs energy, validating EOS root introduces an additional test which can result useful in some cases, see for example the mixture CH4 0.85 H2S 0.15 (SRK-API) , there are more complex examples with Wong Sandler or Huron Vidal mixing rules.

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## tmander

thanks Carlo,
a interesting example, if I understand the point with that option the procedure attempts to validate roots dicharging the points with abnormal density.

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## carlo.stenali

yes, that is the way.
Consider the common test case mixture, 
CH4 0.7 H2S 0.15 CO2 0.15 
at 200 K and 2000 Bar
SRK gives only one root Z = 4.194
is that the value of a liquid or a gas root ? Really a unusual value.
If in Properties you set on Models dialog the Detect Single Phase State to "From Gibbs Energy"
it returns (correctly) a liquid state
the same at 220 K and 2000 Bar
however if you do a calc at 240 K and 2000 Bar with "Gibbs Energy" option the procedure returns vapor state.
Now if you set on Models dialog the Detect Single Phase State to "From Isothermal Compressibilty" the procedure returns liquid state at 240 K and 2000 Bar
What I would say is that there are many options and you should spend some time to understand how they work.

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## tmander

thanks Carlo,
that (detecting the correct single phase) is a quite common problem for all simulators, with EOS I think the selection criteria based on isothermal compressibility is the best in therms of efficincy, some software do calculate a bubble (or dew) line but it is a slow procedure (when doing a lot of t,p flash operations)

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## cmarc

I am calculating 2-Butanol Water VLE at 10 atm in Properties, I suspect regular (for gas fugacity) is not good at that pressure, if I wish to test Peng Robinson (with Wong Sandler mixing rules) should I use the BIPs utility to regress the VLE data (see the previous post by Carlo Stenali) for the specific model adopted ?

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## carlo.stenali

cmarc,
yes, with Wong Sandler you should regress BIPs (you may use the data regression utility in Properties, see "http://www.prode.com/docs/pppman.pdf" for information), there are three (Wilson / UNIQUAC) or four (NRTL) parameters to calculate, the additional parameter being kij , note that the data regression utility can be very slow in some cases, with NRTL (four parmeters to calculate), it takes about 10 seconds in my computer, with complex mixing rules I prefer to set the extended Alpha function (which is the default) as this should reduce errors in vapor pressure correlation (which is important in VLE)

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## cmarc

Carlo,
does Properties use as default for Soave Redlich Kwong and Peng Robinson the TWU Alpha function ? I see in databank the constants A,B,C but these are quite diferent from the values which I got from a different simulator, if I wish to compare VLE results should  I set the SRK, PR Alpha functions ?

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## carlo.stenali

with natural gas mixtures I prefer base alpha function, phase envelopes seem more "realistic" and I am not sure if extended Alpha function does produce reliable results above critical points, see for example a simple methane-n-butane phase diagram calculated with PR and base Alpha function or extended (TWU) Alpha function, I get quite different values
with base 
PC 130 Bar TC 326K CricoT 356K CricoP 133 Bar
with extended 
PC 138 Bar TC 323K CricoT 355K CricoP 140 Bar

said this I must add that with glycole, water, methanol etc. the extended Alpha function works better so it depends from your application.

----------


## cmarc

thanks,
which thermodynamics should I define for a glycol dehydration absorber ?
GPSA chapter 20 has VLE data for TEG and others, what about PR with Wong Sandler mixing rules ?

----------


## carlo.stenali

for TEG (triethylene glycol) and water VLE the PR-WS works well, for enthalpy PR do a decent result, you should set the extended Alpha function as base alpha doesn't fit well these components (other components, usually hydrocarbons, work well).
In the past I did use  PR with specific BIPs getting quite good results (at least at low pressures), however WS or HV mixing rules should do a much better work, you must spend some time for tuning parameters as these mixing rules require at least the Kij

----------


## cmarc

thanks,


if I enter GPSA VLE data in data regression procedure I get a quite good agreement with calculated PR-Wilson parameters, I was not able to find a good agreement (large errors) with PR alone, I set the extended Alpha function as you suggested.See More: Excel library for process calc's including distillation

----------


## rense

can you share an example to plot a tpxy diagram ?

----------


## carlo.stenali

Rense,
there is a Excel page distributed with Properties which calculates TXY and PXY diagrams, look in the Excel directory, you should find a page named tpxy.xls.
I attach the images txy.jpg and pxy.jpg which show the diagrams for pentane-ethanol at 25 Bar and 440 K , the model is Peng Robinson-UNIQUAC with Wong Sandler mixing rules, it is one of the examples includes with Properties, see "www.prode.com" for additional information and examples.

----------


## rense

thanks Carlo,
the capability to print PXY , TXY diagrams from Excel is exactly what I need.
Nice.

----------


## dbert

someone has methyl acetate cyclohexane vle data ? I need to model a system at about 5 Bar

----------


## carlo.stenali

hi dbert,
I have some methyl acetate cyclohexane VLE points at 760 mmHg,

first column X(1)
second column Y(1)
third column temperature in degrees Celsius

0.033000  0.182000    74.300
0.085000  0.350000    68.400
0.142000  0.443000    64.900
0.283000  0.575000    59.700
0.313000  0.594000    59.000
0.373000  0.625000    57.900
0.478000  0.664000    56.800
0.507000  0.673000    56.700
0.616000  0.714000    56.000
0.688000  0.744000    55.800
0.722000  0.759000    55.700
0.781000  0.789000    55.500
0.835000  0.820000    55.550
0.940000  0.914000    55.800

Prode Properties is very useful for VLE/LLE data regression with nonstandard models as for example PR-WILSON or PR- NRTL (Wong-Sandler) which I suggest for this binary, see "http://www.prode.com" for additional information.

----------


## dbert

thank you very much Carlo,
I need also to model cyclohexane-toluene, actually I calculated the PR-Wilson parameters with the UNIFAC option included in the data regression procedure in Properties, do you think UNIFAC is reliable for this binary ?

----------


## ariek

such a great sharing! thank a lot

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## carlo.stenali

for cyclohexane - toluene I have (X1, Y1, T -C-)

0.000000  0.000000   110.560
0.063000  0.156000   107.040
0.142000  0.310000   102.780
0.178000  0.362000   101.250
0.290000  0.509000    96.620
0.313000  0.536000    96.000
0.393000  0.615000    93.390
0.444000  0.663000    91.810
0.534000  0.727000    89.610
0.597000  0.774000    88.050
0.754000  0.865000    85.000
0.890000  0.941000    82.470
0.938000  0.968000    81.730
1.000000  1.000000    80.750

with Properties I calculated the BIPs for PR-Wilson (Wong Sandler mixing rules) with both UNIFAC predictions and measured data then in Excel I generated the two TXY diagrams at 5 Bar,  as you see in this (fortunate) case results are very similar (errors about 1-2 K)

----------


## dbert

thanks Carlo,
very useful data, btw I noticed that for this binary the Peng Robinson standard does a decent job and the selection of extended Alpha function can improve accuracy. I am curious if someone has compared the three parameters TWU formulation with PRSV which uses one empirical factor, Kappa, for fitting pure component vapour pressures.

----------


## mouradbz

Thank you

----------


## carlo.stenali

dbert,
I presume you refer to Stryjek and Vera correlation
alpha = ka + kb*(1-Tr^0.5)*(0.7-Tr)
ka = 0.378893 + 1.4897153*W -0.171318*W^2 + 0.0196554*W^3

generally referred as  PRSV this correlation has been included in Hyprotech simulators, there is a parameter kb which is specific to the fluid of interest.
PRSV works well fro hydrocarbons and other fluids at low temperatures however , it doesn't extrapolate well at high temperatures and you should use another correlation for these cases.
Twu  correlation produces equivalent (or better) results at low temperatures but works well even at high temperatures, so it should be preferred for all applications but specifically to mixtures with fluids in supercritical state.

----------


## dbert

yes, with PRSV I mean the Stryjek and Vera  extension of Peng Robinson, I would be interested in comparing results agaisnt the three parameters TWU included in Properties ans simulators as PRO II, Orbey and Sandler in their book modeling vapor liquid equilibria chapt. 3.1 suggest TWU for mixtures that contain fluids in supercritical state, this is common with natural gas, however I presume that three parameters could provide a better fitting of vapor pressure and density.

See More: Excel library for process calc's including distillation

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## mderra

dbert,
I did some tests for natural gas mixtures, when calculating phase envelopes for streams containing C1, C3... and heavy components (C10 and higher) with Twu (Properties) and PRSV (Aspen) TWU shows better results, email me a message for additional information

----------


## mpat

mderra,
working mainly with natural gas I use the base SRK API  exstension (Graboski & Daubert ) which works well but I am curious to evaluate the features of extended correlation, could you email to maurice.patton@gmail.com ? 
Thank you.

----------


## rense

I wish to evaluate ethanol n-heptane equilibria at 15 BAR, can you share some VLE data points ?

----------


## carlo.stenali

Rense, I have BIPs for  PR-NRTL Wong Sandler Mixing rules, extended alpha function , BIPs are from Properties database

K12 0.134808
A12 1528.91
A21 2047.97
G12 0.336973

I attach 
TXY diagrams at 2 Bar and 15 Bar
PXY diagram at 333 K
you can compare PXY at 333 K with that included in Modeling Vapor Liquid Equilibria (Orbey and Sandler)

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## carlo.stenali

I attach PXY for ethanol n-heptane at 333 K , you may compare with that included in Modeling Vapor Liquid Equilibria by Orbey and Sandler

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## rense

thanks Carlo,
the PXY diagram shows well the phase equilibria behavior of ethanol heptane at low pressures, however the predicted phase equilibria @ 15 Bar (the condition which interest me) seems more regular.

----------


## mderra

I am modeling water-ammonia system, do you have suggestions for fugacity and enthalpy models ?
Operating conditions 18 Bar

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## carlo.stenali

mderra,
my copy of Prode Properties does include several BIPs for water ammonia (see image), I attach a few values

WILSON 158.447 -1227.49
NRTL -2191.2 1305.86 0.105957
UNIQUAC -1009.48 -291.765
SRK -0.283201
PR -0.268977
PR-NTRL-WS -0.10489 -6801.87 6754.34 0.0258625
PR-WILSON-WS -0.873655 1580.5 -1484.45
PR-UNIQUAC-WS 0.0700976 -1363.7 -513.344

perhaps accepting some errors you can adopt PR, SRK with standard mixing rules for enthalpy, fugacity at 18 Bar (however complex mixing rules are available)

----------


## mderra

thanks, 
I have found PR (with extended alpha and kij -0.268977) reasonably good for this binary.

----------


## Almart

I am simulating a distillation column (30 trays, feed at tray 14, reboiler, total condenser) with Prode, 
can I specify a flow rate for a component at bottom ?

----------


## dbert

Almart,
I have utilized the application example column.xls distributed with Prode Properties, it allows to specify component's flow rates and fractions at top and bottom of the column.
There are cells where you define the specification's type (reflux ratio, ratio top to (total) feed, bottom to (total) feed, component's fraction in product and  component's fraction at bottom).
Perhaps you can provide some additional details on the specific problem.

----------


## Almart

thanks dbert,
it's the classical azeotropic distillation for separating ethanol from water with the help of benzene, feed is 95% weight alcohol.
Prode works well at low pressure (2 Bar) and at that pressure I can use a model based on activity (NRTL), however I wish to simulate the column at higher pressure and set a purity.
I think to use a complex mixing rule for VLE (Peng Robinson + NRTL , Wong Sandler mixing rule) and LKP for enthalpy.


I am quite interested to evaluate the results.See More: Excel library for process calc's including distillation

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## dbert

azeotropic distillation interest mee, too.
I have not simulated ethanol water separation, however I suspect VLE with EOS and complex mixing rules will be more difficult to converge than ideal + NRTL model.

----------


## Almart

yes, with complex mixing rules solving a distillation column is a very slow process, 
in some cases it doesn't converge and one must be careful,
I wish to compare different methods, 
as far I have found little differences at low pressures, at high pressures things are much more complex, as said.

----------


## carlo.stenali

I have been informed that there is a maintenance version of Prode Properties available for download from "http://www.prode.com"
Among other things as a large BIPs data bank there are some new models as ISO 18453 (GERG 2004) the ISO standard for calculating VLE of water in natural gas mixtures...

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## rense

thanks,
I work in natural gas industry and these models are useful.

----------


## rense

I did a little testing and I would say that there are several interesting features, GERG support is good as that is becoming the standard for natural gas properties but I see also a large databank for BIPs (which covers all standard models) and several other interesting things.

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## carlo.stenali

Prode Properties version 1.18 did support ISO 18453 and GERG 2008 however these models were available only in extended versions, now base version does include ISO 18453  and a large collection of BIPs (more than 22000 data sets)

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## mderra

thanks Carlo,
it seems that Prode has a leading product for natural gas applications, Properties includes the most used models, SRK,  PR, AGA and GERG plus all the models for chemical's applications and a large number of BIPs.
Nice software.

----------


## ruudoleo

If i wan't to download one of those files i get a avast warning  (win32:malware-gen high risk).
Don't know what it does but be carefull certainly from a company internet connection.
warning comes at the code download?aspxfname=ppp.exe|>{app}\proindex.exe

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## carlo.stenali

ruudoleo,
have you got the software from "www.prode.com" site ?
You can do as I did :
1) download the software from prode and install on computer, 
2) then do a online scan in different sites for the file proind.exe which you mentioned,
I have tested the file in three different sites and I attach one result (from "http://virusscan.jotti.org/") no problems at all for 20 different antivirus,
perhaps there is something wrong in your system 
(I do not know Avast but when more than 50 well know tools say there are no problems I would suspect the problem is in the tool which says different...)  
Carlo

----------


## mrbabu

dear sir,
are  bipolar interaction parameters calculated from experimental data or with predictive methods ?
Thank you,
MrBabu

----------


## carlo.stenali

MrBabu,
BIPs in Prode Properties have been calculated from the experimental data available in DECHEMA and DDB, Base version of Prode Propertie includes (according the developer) more than 23000 BIPs which is a number larger than much more expensive process simulators.
You may read this page (or twitter post) for additional information
"http://www.facebook.com/pages/Prode/174678329259944"

----------


## carlo.stenali

MrBabu,
BIPs in Prode Properties have been calculated from the experimental data available in DECHEMA and DDB, Base version of Prode Propertie includes (according the developer) more than 23000 BIPs which is a number larger than much more expensive process simulators.
You may read this page (or twitter post) for additional information


"http://www.facebook.com/pages/Prode/174678329259944"See More: Excel library for process calc's including distillation

----------


## cmarc

thanks Carlo,
a large collection of BIPs is a very useful feature (especially for recent models as EOS with complex mixing rules).

----------


## mrbabu

thanks, 
I have two questions about Prode Properties for the expert guys in this thread:
a) I wish to calculate VLE with EOS based models and BIPs from Prode databank, for the best accuracy should I set Base or Extended Alpha correlation ? 
b) I understand Joule Thomson coefficent has value dT/dP, 
actually I get very small values, the macro
=StrGJT(1)
in a Excel cell returns the value 6.75E-6 for a natural gas mixture, which Units does the program use ? Can I change the units for Joule Thomson ?

----------


## carlo.stenali

mrbabu wrote:
>a) I wish to calculate VLE with EOS based models and BIPs from Prode databank, for the best accuracy should I set Base or Extended Alpha correlation ?
>b) I understand Joule Thomson coefficent has value dT/dP,
>actually I get very small values, the macro
>=StrGJT(1)
>in a Excel cell returns the value 6.75E-6 for a natural gas mixture, which Units does the program use ? Can I change the units for Joule Thomson ?

a) my rule of thumb : I select Base Alpha Correlation when working with hydrocarbons as that permits to replicate the results from different software as process simulators etc. while I select  Extended Alpha Correlation when working with polar or equivalent fluids.
You may contact Prode for additional information.

b) the default units for Joule Thomson (gas and liquid phase) are Kelvin/Pascal which explains the value you have calculated, you can multiply by 1.0E5 to convert to Kelvin/Bar or you can change the units , to change the units access the Prode Editor and select Config and Units, then in the units dialog (see the attached image) select the correct unit for Joule Thomson, you can select K/Pa, K/Bar, R/Psi

----------


## mrbabu

thanks Carlo,
problem solved, now Joule Thomson values for natural gas mixtures agree well with the documentation

----------


## Crob

can you suggest a detailed reference (with correlations) for the methods (viscosity, thermal conductivity) included in Prode Properties ?
Thank you.

----------


## dbert

I would recommend to read 
"The Properties of Gases and Liquids" by Prausnitz, Poling, Connel

my copy has chapter 9 devoted to viscosity, for the case of gases there are two steps, Prode Properties has low pressure gas viscosities (temperature dependent correlation)  for 1500 pure fluids, as first step you estimate the low pressure gas viscosity for the mixture then you can calculate the viscosity at operating pressure by calculating the correction for the operating pressure.
A similar approach for thermal conductivity.
For liquids there are different procedures but you can find a general description in the book.

----------


## Crob

thanks dbert,
The Properties of Gases and Liquids  is indeed very good and I would definitively recommend the book to everyone working in process engineering.
On the specific I calculated with Prode Properties some test cases given in the book for viscosities of gases at low and high pressures,

example 9.10 Ammonia

420K 1Bar value given in book 146 microP, calculated value (Properties) 146

420K 300Bar value given in book 571 microP, calculated value (Properties) 435

example 9.11 Isobutane

500K 1Bar value given in book 120 microP, calculated value (Properties) 131

500K 100Bar value given in book 261 microP, calculated value (Properties) 243

example 9-14 Use the TRAPP method to estimate the viscosity of a mixture of
80 mol % methane (1) and 20 mol % n-decane at 377.6 K and 413.7 bar

at these conditions Properties (with Soave Redlick Kwong model) calculates a liquid molar fraction of 0.781 and gas composition is different from that provided in example so I have tested only low pressure data with good agreement.

Similar results for thermal conductivities.

On the average I found errors of about 10% which are acceptable for my purposes.

----------


## dbert

interesting evaluation, 
if I may add a note I think there is an error in mixture with  80% CH4 and 20% C10H22, for this mixture Prode Properties calculates the attached phase envelope,

Pc 240 Bar
Tc 497K
Cricondenbar 320 Bar
Cricondentherm 545 K

your test conditions are outside the VLE area (above cricondenbar) so I expect all liquid or all gas (you may add the test for isothermal compressibility),
kindly advise if I am wrong.

----------


## Crob

dbert,
you are correct, Prode Properties calculate a single phase at those conditions,
most probably I did wrong cause I just did the same mistake again (setting wrong operating conditions on the Properties Editor),
the program itself is very powerful but easy to use so one may forget how complex these calc's are...

----------


## adarshsv

thanks

----------


## rense

I need the limits and field of application of the ISO 18453 model included in Prode Properties.
I have not the paper, I see that Prode Properties calculates values (for isothermal flash, dew and bubble points) in the temperature range 230-320 K and above but I would need to know the estimated errors also considering the component's mole fractions.

----------


## carlo.stenali

the standard ISO 18453 has these limits

Base
Pressure 0.5MPa..10Mpa
Temperature -15C..+5C

Extended
Pressure 0.1MPa..30Mpa
Temperature -50C..+40C

Composition
CH4 >40%
N2 <55%
CO2 <30%
C2 < 20%
C3 < 4.5%


iC4 < 1.5%
nC4 < 1.5%
iC5 < 1.5%
nC5 < 1.5%
C6+ < 1.5%

do you need also the expected errors ?See More: Excel library for process calc's including distillation

----------


## rense

thanks Carlo,
I expect errors for water dew point within 2 K for that range, is this presunction (based on your recent post) correct ?
As alternative do you suggest SRK or PR with complex mixing rules ? 
The problem there would be the avilability of BIPs for hydrocarbons-water binaries

----------


## stawad

I have installed the software, I wish to calculate in Excel a separation column with two feeds, reboiler and total condenser.
My specification is on distillate purity, where should I define the specification ?
Thank you,
Stawad

----------


## carlo.stenali

Prode Properties does permit to specify the desired component fraction of a component in distillate (top) or bottom,
and you can solve the column and get the results directly in Excel, 
in my opinion it's very easy and useful if you need to do some additional processing.
I'll show you how to proceed, 
load the predefined Excel pace column.xls (distributed with Prode Properties) 
on row 23 change the specification type to 5 to specify a component fraction in bottom
on row 24 change the value to 0.001 to define the desired molar fraction
on row 25 change the value to 3 to define the component in the list

see the attached columnspec.jpg for additional information

then click on Solve Column to get the solution, 
for the feed with composition C2 0.0812325 C3 0.30251 iC4 0.0840336 nC4 0.214753 nC6 0.31746 (click on Feed1 to edit the composition, see columnfeed.jpg) 
the procedure calculates the reflux required as 2.685 , 
the molar flow of iC4 at bottom is 8.26E-6 = 0.008263 * 0.001 
where 0.008263 is the flow (liquid) at bottom
you can change the required molar fraction (row 24) to 0.0001 and the procedure will calculate a reflux of 7.4 and so on...
To specify a component fraction (purity) in distillate , change the value on row 23 to 4 which means a specification for a component fraction on top, then in rows 24 and 25 enter the desired fraction and the component

Take care to enter specifications which you expect possible for that column, that is not easy to figure, I would suggest before to enter specifications on component's fractions to solve the column with different reflux and see how compositions change at top and bottom

----------


## psensel

what a find !
I found "www.prode.com" with google and it's really good,
according my experience solving with Prode a distillation column in Excel is very easy,
thank you.

----------


## stawad

thanks carlo.stenali,
I see now where the problem was,
when solving a column in Prode Properties the specifications 4 and 5 require the molar fraction in top or bottom streams, not the component's fractions...
That's ok , it may require some additional work (converting from component fractions to stream's fractions in case one wish to specify the total recovery of a component) but it gives the required flexibility.
I see that column in  Prode Properties doesn't require initialization which is good, how much reliable is the convergence ?

----------


## mderra

Hello Stawad,
I solved several separations with Prode Properties (std. columns with one or two feeds + reboiler and condenser bot partial and total) with the same results as in client's process simulator,
which kind of column do you wish to simulate ?

----------


## carlo.stenali

Stawad,
that's a limit in student's version, 
normal version supports both specified fraction of a component in top or bottom streams and recovery fraction of a component in top or bottom streams, the difference being that with recovery the fraction is calculated relative to (total) feed.
Specify a Recovery fraction is useful however in most separation processes you can easily define a priori the required (specified) fraction in distillate or bottom so in my opinion one can live without that additional specification...

----------


## tinom

you can specify stream fractions or components fraction recovery,
however I recommend to begin solving easy to converge specifications as recycle or distillate flow, 
that will permit a sensitivity analysis (vs. nr. of stages, recycle flow etc.)  to identify the most interesting column's operations

----------


## ibrahimsakr

how can i download files from these site ? .

----------


## carlo.stenali

ibrahimsakr,
actually for downloading Prode Properties you can follow this link

**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]

once completed the form, click on "submit"" button to start download,
note that depending from your connection speed it may take several seconds before to start,
hoping this helps.

----------


## carlo.stenali

ibrahimsakr,
actually for downloading Prode Properties you can follow this link

"http://www.prode.com/en/download.aspx?fname=ppp.exe"

once completed the form, click on "submit"" button to start download,
note that depending from your connection speed it may take several seconds before to start,
hoping this helps.

----------


## stawad

thanks all, now I am able to solve separations.
I have a different question, which are the main differences between multiphase gas+condensate+water available in Prode Properties and water decant option available in many simulators ?


Do the resulting liquid and gas fractions be different ?See More: Excel library for process calc's including distillation

----------


## carlo.stenali

typically with water decant option water is considered a separate phase and modeled with his vapor pressure as calculated by specific correlation, there is no inclusion of cross compositional interactions between water and other components.
In Prode Properties with multiphase option (gas-liquid or gas-liquid-solid) fugacities are calculaled with selected models and cross compositional interactions considered, this can produce different results in most cases and specifically with complex mixing rules as Wong Sandler or Huron Vidal which are very sensible to compositional interactions...

----------


## stawad

I am calculating mustiphase equilibria at different conditions for a mixture of 15 components (C1-C13 + water , CO2, N2...) , typically when liquid and water contents are not negligible I get water as separate phase which is ok according my experience, however there are cases where I get vapor + two condensate phases (with different compositions) + water (a total of 4 phases) , which is the meaning of this result from a practical point of view ? 
In separation train we have three phase separators (gas, condensate, water), do the two liquid (condensate) phases generate a unique phase ?
That should be, according my experience.

----------


## carlo.stenali

three phase (and two phases) separators work on the basis of different densities of vapor, hydrocarbon's condensate and water.
In many cases hydrocarbon's condensates have densities of about 600/700 Kg/m3 while water around 1000 Kg/m3 so the separator can work fine.
However there are cases where three liquid phases may form (for example a liquid phase with relatively heavy hydrocarbons, a liquid phase with remaining liquid condensate  + water) in these cases the separator may not separate well condensate from water if the densities of liquid condensate phases are very different.

----------


## stawad

I see the point,
in most cases with hydrocarbons + water Prode Properties predicts three phases (gas + hydrocarbon's condensate + water)  however in some cases Prode Properties did predict four phases (gas + three liquid phases) which makes me thinking about, I would guess (as you suggested) that the presence of two "potential" phases of liquid hydrocarbons should not modify the operating of our separation train as these phases to separate may require conditions different  (i.e.longer retention times) that those in our plant...
Is this correct ?

----------


## carlo.stenali

Normally retention time in 3 phase separators is about 3 minutes.
Water/oil separation is based on density difference and settling time can be determined by Stokes law and the distance the particle travels, the vertical velocity component can be estimated as

vv = 1.7886E-6 * (SGo-SGW)dm^2 / Vw

where SGo, SGW specific gravities of Oil and Water
dm droplet diameter microns
Vw water viscosity cp

the horizontal velocity component is estimated as vh = L/T , where L is the length of the separator and T the retention time
Settling velocity and total volumes are then used to determine vessel dimensions, for horizontal separators length to diameter ratio should not be less than 4 to 1 in order to minimize turbulence.
This is the usual design for the three phases gas-oil-water separators, as said this design doesn't allow to reparate two liquid phases with specific gravities very close each other, you should increase retention time or some other parameter.

----------


## tinom

thanks Carlo, nice information,
I would add that I have a good Excel application example for three phase separators design, despite the simplicity of formulation based on Stokes law with two adjustable parameters it works fine fitting well the design provided by our specialized sub contractor.

----------


## mderra

"when solving a column in Prode Properties the specifications 4 and 5 require the molar fraction in top or bottom streams, not the component's fractions..."

when modeling a column you should be able to specify also recovery fraction, specification's codes are
6 component recovery in top product
7 component recovery in bottom product
hoping this helps.

----------


## Crob

thank you for the update.
My question, for natural gas properties (density, dew points etc.) some vendors (Aspen etc.) recommend Peng Robinson, others (Calsep etc.) SRK, which are the suggested areas of application for the different EOS models in Prode Properties ?

----------


## carlo.stenali

my experience:

VAPOR LIQUID EQUILIBRIA
with base alpha correlation for SRK does fit better vapor pressures of components with low values of acentric factor, PR is better for components with acentric gactor of 0.3 or more
with extended (the three parameters Twu utilizes in Prode Properties, Mathias etc.) PR or SRK fo provide eqyuvalnt fitting

ENTHALPY, ENTROPY
there are small differences calculating liquid and gas departures, you must verify for each component or mixture, there is not a better model

LIQUID VOLUMES
there are large errors with both PR or SRK, Peneloux (or equivalent) correction must be applied 


for Vapor liquid equilibria there is not difference between extended PR or extended SR

hoping this helps.

----------


## Crob

thanks carlo.stenali,
I am aware of limited accuracy of PR and SRK when calculating volume of liquid phases, does Prode Properties include the option to correct liquid root with Peneloux (as in Calsep ?)

----------


## mpshah298

thank you
Mihir Shah

----------


## carlo.stenali

Prode Properties does include the Peneloux correction (on liquid volumes and all derivatives) for both Soave Redlich Kwong and Peng Robinson equations of state,
you can set Peneloux correction from Editor (see the attached file) or by code (see the operating manual for additional informartion).


Hoping this helps.See More: Excel library for process calc's including distillation

----------


## cstaff

thank you,
nice software with many features to model petrochemical plants.

----------


## mrbabu

When simulating the gas plant our client adds  a so called "gas saturation unit"  which is available as extension in HYSYS, as far as I understand it gives the possibility to saturate the gas with water, our practice with Prode Properties is to add  water, do a isothermal flash and then get the vapor phase as saturated, results are very close to those calculated with the "gas saturation unit".
I would appreciate comments about this practice.

----------


## dbert

the procedure is correct if you manage to keep the amount of condensate very low (by reducing the amount of water injected), with usual EOS condesnate will not be pure water but it will contain a certain amount of dissolved gas and that will modify the final composition in gas phase.
Altough it is a common practice to include a gas saturation unit you should investigate the validity of the selected EOS with water...
In Prode Properties depending from composition and operating conditions you can select ISO 18453 (Gerg 2004), GERG 2008 or a std. EOS with complex mixing rules.

----------


## imranmlis

Good Source

----------


## carlo.stenali

mrbabu, 
as you correctly noticed the "gas saturation unit" in HYSYS finds the maximum amount of water in vapor phase at specified conditions, you can easily solve that with a isothermal flash.
I do not know why they don't suggest this solution, I can only suppose that users prefer to have a specific icon for that operation.

----------


## Himanshu Parikh

Dear Sir,

can anybody help me how to download excel library for process calculations. my email id is himanshu_parikh@yahoo.com

----------


## carlo.stenali

>Dear Sir,
>can anybody help me how to download excel library for process calculations. my email id is himanshu_parikh@yahoo.com

hello himanshu,
I have verified and the download seems to work fine (at least in my case),
in case of problems you can contact by email the developer, email address is available at

**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]

and ask to receive a copy of the software by email,
size of ppp..exe installation file is about 7 Mb  
Hoping this helps.

----------


## bmat

I am evaluating the solid solution model available in multiphase flash operation of Prode Properties, 
I wish to investigate possible applications for wax precipitation.
I have a few questions,
specifically how the software estimates heat of fusion and liquid and solid heat capacities,
could you help ?

----------


## carlo.stenali

bmat,
the simplified solid solution model in Prode Properties does calculate solid fugacity in multiphase equilibria starting from liquid fugacity and correcting with heat of fusion, liquid and solid heat capacities.
These values are available in Prode Properties databank which includes data for about 1500 chemicals.
Some authors as Firoozabadi, Pedersen and others have tested the ability of the model to predict solid solutions in petroleum fractions / hydrocarbons etc. as for example wax precipitation , in those cases simplified correlations for dHf,cpl,cps can be applied.
I have not direct experience in this area but you can obtain tecnical support from developer.

----------


## carlo.stenali

I have some additional information about the solid solution model in Prode Properties,
since the solid fugacity is calculated from (subcooled) liquid fugacity results depend from selected model for liquid fugacity and BIPs (Kij) , the user can select different models and tune experikental SLE data.
Prode Properties includes a data regeression procedure able to fit

vapor-liquid equilibrium points
liquid-liquid equilibrium points
solid-liquid equilibrium points

the proper tuning of the model is important (as in VLE and LLE) to obtain reliable results.
From a short review of literature it appears that solid solution models similar to that included in Prode Properties have been applied in many different SLE with EOS as SRK, PR, PC-SAFT etc.

----------


## bmat

carlo.stenali,
your information about solid solution model in Prode Properties have been useful to me,
I use SRK for liquid fugacity and the model woks well with hydrocarbons, tuning is required in most cases (where experimenal data points are available) but that is a standard for SLE/SVE,
on the plus side, convergence is very reliable.

----------


## cbadia

I am calculating a separation column for a mixture of benzene, toluene, xylene in Prode Properties,
I see that different specifications are available as component fraction (at top or bottom) and component recovery (at top or bottom) in addition to reflux, ratio of flows, side drawns etc.


My question is, how does Prode Properties manage component fraction and component recovery when I specify a side drawn ?See More: Excel library for process calc's including distillation

----------


## carlo.stenali

> I am calculating a separation column for a mixture of benzene, toluene, xylene in Prode Properties,
> I see that different specifications are available as component fraction (at top or bottom) and component recovery (at top or bottom) in addition to reflux, ratio of flows, side drawns etc.
>My question is, how does Prode Properties manage component fraction and component recovery when I specify a side drawn ? 

in Prode Properties specifications are quite simple to define
-if you specify a component fraction at top (or bottom) the solver attempts to find a solution where the specified component is present with the desired molar fraction in top or bottom stream, for example if you specify water at 0.999 the solver finds a solution where water is present with a molar fraction 0.999 in top (or bottom) stream, this specification could be impossible to solve if you specify in addition flow rates etc., a common case is when you have a feed with a certain flow of component n, if you specify for that component a molar fraction at top = 0.9999 the solver will be unable to solve any specification with distillate flow rate  >  flow of that component at inlet, the same for side drawns
-in general I prefer to specify a component fraction recovery (at top or bottom), this is much more flexible since it is independent from top, bottom and side drawn flows, the solver attempts to find a solution where the flow of the specified component equals feed flow * recovery fraction
Hoping this helps.

----------


## cbadia

thanks Carlo,
I understand that it is better to specify a fraction recovery where possible.
That should solve also the convergence problems found with side drawns...

----------


## acar

thank you very much,
I have found Prode Properties very good and I recommend it !!

----------


## mdep

has anyone attempted to model solid precipitation (liquid-solid SLE equilibria) in Prode Properties with Peng Robinson or Soave-Redlich-Kwong models?
I have base version (no CPA or SAFT included) , I am not sure if a standard EOS can do the work,
thank you for assistance in this matter !

----------


## carlo.stenali

you may obtain reasonably good results for hydrocarbon's liquid-solid equilibria in Prode Properties utilizing Soave Redlich Kwong or Pend Robinson models but that depends from composition, with very heavy components a statistical approach (SAFT) can offere several advantages, in most cases CPA is a good alternative.

----------


## sayedfarhanali

Thanks for Sharing Nice source for Calculations

----------


## mdep

thanks carlo.stenali,
I wish to evaluate the fraction of heavy component's  (C10+) which will precipitate when temperature goes below -10C
Prode Properties is able to calculate the solid fraction but I have not tuned the model and kijs for heavy components are set to 0.0
I have not idea how the accurate are the results.

----------


## carlo.stenali

if mixture doesn't include water and similar components (only hydrocarbons and inerts) then Peng Robinson or Soave Redlich Kwong may be able to do the work,  
differently I would suggest a model as SAFT or CPA (Cubic Plus Association) with inclusion of association contribute.
Prode Properties (extended version) includes SAFT and CPA, you may contact the developer for additional information
"http://www.prode.com"

----------


## acar

Carlo, does the CPA and SAFT models in Prode Properties include the association contribute ?

----------


## carlo.stenali

in my version (extended) of Prode Properties, CPA (Cubic Plus Association) and SAFT (Statistical Associating Fluid ...) do include these assciation schemes

1a,
2a
2b
3a
3b
4a
4b
4c

as far as I know 1a is for organic acids, 2b and 3b for alcohols and so on...
I have little experience with SAFt as I utilize mainly CPA for mixtures of hydrocarbons with water.

----------


## acar

thanks Carlo,
the reported association schemes should permit to model glycols, water and alcohols which are the chemicals which interest me.

----------


## fmat

Cette software est tres bon et efficate et bien intgr avec Excel !

See More: Excel library for process calc's including distillation

----------


## matrenel

carlo.stenali,
thanks for keeping us updated about this very good product,
I have a question, does CPA model work for VLE only or all phase equilibria etc. calc's ?

----------


## carlo.stenali

hello matrenel,
my (extended) version has both CPA and SAFT, 
I have little experience with SAFT but I utilize quite frequently the Cubic Plus Association model for phase equilibria of water with hydrocarbons,
CPA is available for fugacity (all phases) and volume (density), I believe that also other properties may be available but you should contact the developer for additional information (and cost).

----------


## matrenel

carlo.stenali,
thanks for the answer, I have been in contact with the developer, 
we are more interested in SAFT model (with association), 
for SAFT Prode says that different properties as enthalpy and entropy (and derived properties as cp, cv etc.) are available as extended version of the library, which makes Prode Properties very interesting for our company.

----------


## mrbabu

does anyone have access to Dechema / GPSA experimental VLE data for water/hydrocarbons?
I have been investigating applications of the Cubic Plus Association model in Prode Properties but I have a limited number of interaction coefficients for water-hydrocarbons and no experimental data required by data regression utility available in Prode for estimating interaction coefficients...
Help will be appreciated.

----------


## carlo.stenali

you can find interaction coefficients for CPA ( Cubic Plus Association ), SAFT etc. in several textbooks as Thermodynamic models for industrial applications.
The availability of reliable vle data for water/light hydrocarbons being not easy, there is a Dechema collection but I do not know where you may find a free copy 
Carlo

----------


## hans23

association models as Cubic Plus Association (CPA) and SAFT are very good for modeling mixtures including components capable of hydrogen bonding, these are a large part of fluids in industrial plants, I mention water, acids, amines, glycols etc.
These models offer many advantages in terms of accuracy, I have compared water-hydrocarbons VLE calculated with CPA and Peng-Robinson Huron-Vidal (and Wong Sandler) and results from CPA are equivalent or better.
Also Prode Properties includes the data regression utility for calculating VLE/LLE/SLE Kij, Lij (both pairs) interaction coefficients.
This is a really good software and I hope that many engineers will consider with interest this alternative...

----------


## mrbabu

thanks carlo.stenali and hans23,
I have several natural gas streams with mainly methane but with H2S, water and CO2 too,
I have read that CPA (Cubic Plus Association) is better than Peng Robinson and Soave Redlich Kwong,
I wish to compare the two variants (CPA Peng Robinson and CPA-Soave Redlich Kwong) available in Prode Properties,
before to compare results I wish to tune the interaction parameters (there are two intercation parameters Kij and Lij for each binary),
I understand that the best way to calculate these parameters is to utilize the data regression procedure available in Prode Properties but this procedure requires experimental VLE data points which I do not have...
I could use some interaction parameters which I have found but I am not sure about final accuracy.

----------


## carlo.stenali

I think you are correct about tuning the CPA models with the same experimental data before to compare the results, the data regression procedure available in Prode Properties is good for that,
as said I do know only a few sources (Dechema, DDB, GPA) for VLE data,
there could be some data available from the Korean Thermophysical Properties Databank (see the reply to your post in eng-tips) but I am unable to access that site and I can't confirm.

----------


## hans23

Hydrate formation curve in Excel

Prode Properties 1.19 includes a utility which allows to calculate the hydrate formation curve directly in Microsoft Excel,
the distribution files include a Excel page hydrate.xls , from this page one can define composition including all common hydrate formers
C1 Methane,
C2 Ethane,
C3 Propane,
C4 n Butane
C4 i Butane
N2 Nitrogen
CO2 Carbon Dioxide
H2S Hydrogen Sulfide

plus inhibitors as Methanol, Ethanol, Glycol and salts (salts require the electrolyte package)

Hydrates modeled according van der Waals and Plateeuw (rigorous, statistical approach) and Cubic Plus Association (CPA) for vapor, liquid phases
A free students version is available from Prode WEB Site

----------


## mpat

I am calculating with Prode Properties the hydrate formation curve for a natural gas mixture,
components C1...C10 plus N2, CO2, H2S , no inhibitors
I see that resulting values change when
a) I enter only the hydrate formers or all components
b) I specify an amount of water
I would presume that introducing heavy hydrocarbons and water change the fugacity of both gas and liquid phases then affecting the hydrate formation curve.
Is that correct ?
Thank you for help

----------


## carlo.stenali

with Hydrates model in Prode Properties, you should enter the full composition as the procedure calculates fugacities of different components in gas and liquid (with condensate) phases.
The amount of water has importance for phase equilibria and when inhibitors are present.
Frequently the amount of inhibitors is specified as mass fraction, Prode Properties allows to enter molar or mass fractions so you can convert weight fraction to molar and molar fractions to weight.
Also you can enter fractions in range 0-1 or 0-100.

----------


## asanter

There is a method in Prode Properties for pipelines simulation, 

Simulation of single phase, two-phases, multiphase flow on circular pipes (* available in extended versions)
int res = PIPE(int stream, int model, double diam, double rough, double length, double dHeight,
double dHeat)
models
Beggs & Brill / Hazen-Williams / AGA



I wish to simulate a transport pipeline (multiphase, hydrocarbons + water) , model Beggs and Brill, 
does Prode Properties calculate heat balance if I specify the a dh (air/soil heat exchange) ?See More: Excel library for process calc's including distillation

----------


## carlo.stenali

asanter,
method PIPE in Prode Properties allows to specify the heat exchanged with soil / air / water ,
Prode Properties then calculates final temperature, pressure and phase equilibria,
you can specify the heat exchanged on each segment of the pipeline,
for long pipelines you may have different external conditions ( soil / water / air ) in different segments,
before to simulate a pipeline you need to evaluate the influence of surronding materials say dry earth, sand and/or gravel etc. this 
may require some time but it's important for the accuracy of results.
In some cases (change of phase, high viscosity liquids) the influence is greater than in standard gas pipeline.

----------


## asanter

Carlo,
thank you for the answer,
I am simulating a 10 kilometers pipeline (natural gas + condensate),
we expect a different amount of condensation depending from external conditions,
which is the unit in the method PIPE for the heat exchanged with soil ?

----------


## carlo.stenali

with Prode Properties, method PIPE, when simulating a segment of a pipeline you can specify the amount of heat exchanged with surrounding environment using the same units of flash operations (H-P)
As you know in Prode Properties all the units of measurement are easily customizable so you can define standard US, SI or different units.

----------


## mpat

Hydrate software
I calculated hydrate formation curve in Excel with the rigorous model included in Prode Properties, 
comparing hydrate formation conditions in presence of different amounts of methanol as inhibitor with experimental data from Sloan's 
book I observe low errors for methanol weigh fractions below 20-30%,
Hammerschmidt's equation (utilized to predict influence of inhibitor) gives equivalent or higher errors, 
my question : which is considered (engineer's best practice) the maximum amount of methanol to add into a natural gas stream ?
My client says they utilize up to 30% (weigh fraction) , is that figure generally accepted?

----------


## asanter

there are economical reasons which may put a limit,
we have evaluated Methanol, MEG, and NaCl ,
to get a depression of about 10 C in hydrate formation temperature about 32% (weight) of MEG is required, 
with 30% (weight) of methanol loss in gas phase is about 500 kg / MSm3 , much lower with MEG

----------


## abarre

I use Prode Properties for calculating the phase envelope
of natural gas mixtures including some water, CO2 and H2S,
I would appreciate comments from experts about the package to utilize,
Prode Properties includes many variants of SRK, PR plus CPA, ISO 18453 etc.
the resulting phase envelope could differ sensibly depending on the model and the options.

----------


## carlo.stenali

for phase equilibria in mixtures of hydrocarbons+water+carbon dioxide+hydrogen sulphide
I would select a EOS with complex mixing rules (Wong Sandler or Huron Vidal in Prode Properties)
you may try CPA too.

----------


## abarre

thanks Carlo,
at last I decided to select  Peng Robinson with Wong-Sandler mixing rules for phase equilibria,
depending from model selected for activity coefficient model (there are three variants in Prode Properties, PR-Wilson, PR-NRTL, PR-UNIQUAC) there are three or four parameters which may require some work when not available.
However it seems to fit well some experimental data which I have.

----------


## carlo.stenali

abarre,
according several papers Peng Robinson with Wong Sandler mixing rules can give good results for hydrocarbons + water,
possibly you need to tune parameters,
Prode Properties includes the data regression utility for that.

mpat,
I think asanter has just replied to your question,
different companies can adopt different practices but at last you have to calculate and compare the costs and benefits of different solutions

----------


## stawad

Co2 freezing point with Prode Properties
I am calculating Co2 (in natural gas) freezing point with Prode Properties,
according your experience which is the correct option as thermo package ?
Peng Robinson and Soave Redlich Kwong packages give quite equivalent results.
Thank you.

----------


## carlo.stenali

with multiphase vapor-solid equilibria in Prode Properties I have tested methane-Co2 and some other mixtures with Soave Redlich Kwong and Simplified Solid Model available in Prode Properties,
errors for freezing point temperatures are in a range from 1 to 5 C compared with experimental data,
I have not verified Peng Robinson but I presume it gives equivalent accuracy (I may be wrong)

----------


## abdullah7877

thanks

See More: Excel library for process calc's including distillation

----------


## cbadia

to simulate a pipeline startup (dynamic simulation with method of characteristics) I need to calculate the Isothermal compressibility of hydrocarbon's condensate,
Prode Properties gives several options based on EOS (Peng-Robinson, Soave Redlich Kwong, CPA) and other methods as BWRS etc. 
I have to solve the system for different pressures (from 0 to 120 Bar) and the values of isothermal compressibility are not constant, which is the best option: keep the value of isothermal compressibility fixed or input a table of values ? 
The composition doesn't change when operating at pressures above 10 Bar while a little amount evaporates at low pressure, however the value of isothermal compressibility shows only a limited variation at low pressure.

----------


## carlo.stenali

Hans23 has given this answer
"possibly (for transient analysis) you need the bulk modulus,
isothermal bulk modulus is the inverse of isothermal compressibility,
with many hydrocarbons the value of isothermail compressibility and bulk modulus have limited dependence from pressure,
for example for CH4 at 100K

p 1 Bar ->0.000198 1/Bar
p 10 Bar ->0.000194 1/Bar
p 50 Bar ->0.000175 1/Bar
p 100 Bar ->0.000157 1/Bar

values calculated with Prode Properties Soave Redlick Kwong Extended
as you see from 1 to 100 bar the difference is about 20% , I think you can assume the value as constant"

I agree with Hans23, when doing transient analysis my software requires one value for the bulk modulus, 
generally I enter one (averaged) value.

----------


## salah_calimero

Salam alaykom,

How can i download this application please

Thnaks

----------


## carlo.stenali

wa alaikum assalam

you may download the free student's versions from this page
'http://www.prode.com/en/download.htm'
'http://www.prode.com/en/properties.htm'

----------


## cmarc

how to model a blow down scenario with Prode Properties

I am modeling a blow down with Prode Properties,
my usual option to simulate the orifice plate (adianbatic, irreversible expansion) is the HPF() flash,
however I was informed that Prode Properties has a constant energy flash able to solve the specified enthalpy plus kinetic energy, 
which are the advantages of this option ?

----------


## carlo.stenali

cmarc,
Prode Properties (extended version) solves different types of flash operations, 
in addition to isothermal multiphase (specified t and p) and phase fraction (specified phase fraction and state) operations there are

double t = HPF(integer stream, double p, double dh)
Given a stream, final pressure and heat added (or subtracted if negative value) method solves the flash operation (enthalpy
basis) and returns final temperature

double p = HTF(integer stream, double t, double dh)
Given a stream, final temperature and heat added (or subtracted if negative value) method solves the flash operation (enthalpy
basis) and returns final pressure

double t = SPF(integer stream, double p, double ds)
Given a stream, final pressure and heat added (or subtracted if negative value) method solves the flash operation (entropy
basis) and returns final temperature.

double t = STF(integer stream, double t, double ds)
Given a stream, final temperature and heat added (or subtracted if negative value) method solves the flash operation (entropy
basis) and returns final pressure.

double t = EPF(integer stream, double p, double ain, double aout, double dh)
Given a stream, final pressure, inlet and outlet areas and heat added (or subtracted if negative value) method solves the
constant energy flash (energy calculated as sum of enthalpy and kinetic energy) and returns final temperature.
this method permits to model adaiabatic, irreversible expansions when the contribute of kinetic energy cannot be neglected.

the last **EPF** solves the constant energy flash, 
**this method permits to model adiabatic, irreversible expansions when the contribute of kinetic energy cannot be neglected**
it may offer many advantages (over HPF and SPF) when modeling orifice plates.

----------


## cmarc

thanks carlo.stenali,
I understand that EPF() method in Prode Properties solves the constant energy flash (where the energy is calculated as sum of enthalpy and kinetic energy), 
as said I am modeling a blow down with Prode Properties, I am comparing results of EPF() against HPF() flash operations where the first is for constant energy the second for adiabatic flash,
I have read (DNV literature) that the constant energy flash should provide better results in these cases,
have you experience with this operation ?

----------


## carlo.stenali

I have used EPF() for a limited number of cases as
to model the expansion from vessel (stagnation point) to the nozzle
to model the expansion from the nozzle to the atmosphere
generally I model valves with the adiabatic flash (method HPF in Prode Properties)

----------


## cmarc

thanks Carlo,
I agree that HPF() or SPF() flash operations are a natural choice with valves but the constant energy flash is a useful alternatiive...
Prode Properties has a really powerful set of flash operations including adiabatic and isentropic multiphase which are not available (as far as I know) in other software...
really impressed with the features of this software :-))

----------


## carlo.stenali

cmarc,
actually Prode includes a complete set of flash operations supporing true multiphase and reactions (in extended version)
as far as I know these features are not available in other commercial products (may be some university tool).
From my point of view the most interesting feature is the flexibility given by Prode + Excel or Matlab,
I can solve most engineering problems easily and quickly and I have complete access to the code to change, update or modify something.

----------


## fval

thank you very much for this software !!!
I have installed Prode Properties on my computer and I was able to simulate a centrifugal compressor process given the adiabatic efficiency, how can I calculate the same compressor if I know the polytropic efficiency ?

----------


## carlo.stenali

you can easily solve the polytropic compressor with Prode Properties,
there is a specific unit in extended version (please contact Prode at 'www.prode.com'), 
that unit solves the model with the desired level of accuracy (it's a iterative procedure), 
however you can obtain equivalent (or very close) results by modeling the polytropic compressor as a series of isentropic units with predetermined polytropic efficiency, 
this is very simple with Prode Properties, for additional information see

'http://www.prode.com/docs/pppman.pdf' 

-decide the number of steps (I suggest 5 steps) and calculate the dp as (Pout-Pin) / nr. of steps
-start from compressor inlet temperature and pressure
-at these conditions calculate cp with the method =StrGCp and cv with the method =StrGCv , calculate k = cp/cv
-calculate n (polytropic exponent) as n = polytropic efficiency * (k-1)/k   


-calculate P1=Pin+dp and T1 = Tin*(P1/pin)^(n-1)/n  
-at these conditions (P1,t1) calculate cp with the method =StrGCp and cv with the method =StrGCv , calculate k = cp/cv
-proceed until to complete the steps
-....
-once you have calculated the final (outlet) temperature you can calculate the enthalpy at inlet conditions (with Prode Properties) as H1 = StrH()  and outlet conditions H2 = StrH() the difference being the enthalpy rise in the gas, you can then calculate the polytropic head from polytropic efficiencySee More: Excel library for process calc's including distillation

----------


## asanter

does the vessel depressurization / blowdown utility in Prode Properties allows to modify the parameters of vessel's volume and wetted area ?
I am able to simulate the depressurization / blowdown but I need to customize the different parameters cause our vessel's typology is not standard. 
(by the way I have the same problem with simulators, I hope that Prode can solve the problem)

----------


## carlo.stenali

you may contact Prode and ask for the depressuring utility in Excel,
it's a page with VBA code which you can easily customize.
The procedure is based on a paper presented by Prode at 1994 simulation conference.

----------


## cbadia

for a two phase discharge I am sizing a relief valve with the isentropic Nozzle unit available in Prode Properties,
the procedure allows to specificy the HEM (Homogeneous Equilibrium Model) and NHNE (Non-Homogeneous Non-Equilibrium Model) for isentropic flow.
While the HEM model gives results consistent with those calculated by Excel page nozzle.xls distributed with the program the NHNE model requires specific settings and may give results quite different.
Which is the best option (HEM or NHNE) for modeling a PSV discahrge ?

----------


## carlo.stenali

I think it depends from several factors as for example the size of the valve and the physical properties of the fluid,
my version of Prode Properties has three models
HEM (Homogeneous Equilibrium Model)
HNE-DS (Homogeneous Non Equilibrium, simplified model)
NHNE Non Homogeneous Non Equilibrium)
the last two require a specific parameter which for HNE-DS is available in several papers while for NHNE you have to estimate the value, generally I select HEM and I do a test with HNE-DS

----------


## cbadia

thanks Carlo,
I have found several papers discussing this topic, one is "Improved control valve sizing for multiphase flow" from Hydrocarbon Processing March 200, the authors say "HNE-DS method basically assumes that the flow pattern in the control valve is homogeneous but gas and liquid are not in equilibrium  a non-equilibrium factor N represents the boiling delay"
your comment agrees with this statement.
By the way I found also an interesting thread comparing API PSV formulation for gas flow here

'http://www.cheresources.com/invision/topic/16104-psv-discharging-temperature'

the author has provided a Excel page to compare different procedures

Discharging temperature (PSV outlet)
1) calculated with isentropic + adiabatic flash (the default in nozzle.xls)
2) calculated with adiabatic flash
3) calculated with isentropic flash

Calculated Area
1) rigorous numerical solution of isentropic nozzle
2) API formulation for gas and vapors, ideal cp/cv
3) API formulation for gas and vapors, real cp/cv
4) API formulation for gas and vapors, real cp/cv, Zv = 1

all the required properties are calculated by Prode library , for personal/academic use you can download a  free -with limited number of components- copy from 'www.prode.com'

I recommend to read this thread to everyone interested in PSV sizing.
**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]

----------


## dchernandezs

Thanks a lot for the information

----------


## cmarc

I have found a interesting tread at Cheresources discussing the polytropic model with phase equilibria in Prode Properties, I include the parts which show the numerical examples as they could be of interest for the readers

consider the case of methane compressed from 300K 10Bar.a to 40Bar.a

with efficiency = 1 (isentropic compression) the ideal gas model gives

cp/cv (tin,pin) = 1.3327 (Soave Redlich Kwong)
(k-1)/(k*eff) = 0.249
tout = tin*(pout/pin)^(k-1)/(k*eff) = 424K

with the rigorous model (Prode Properties) we get as tout = 409K

relative error (424-409)/(409-300) = 13%

now if we set a efficiency = 0.5 we get

(k-1)/(k*eff) = 0.499
tout = tin*(pout/pin)^(k-1)/(k*eff) = 599K

with the rigorous model (Prode Properties) we get as tout = 525.7K

relative error (599-525.7)/(525.7-300) = 33%

now if we add the contribute of phase equilibria (polytropic solution with phase equilibria model) we can observe large differences in tout-tin mainly due to the contribute of enthalpy of vaporization,

consider the case of the mixture methane 0.8 n-Butane 0.2 (molar fractions) compressed from 10Bar.a to 40Bar.a
with a polytropic efficiency = 0.75 , model Peng-Robinson

this mixture has a dew point of 287.9 at 10Bar.a then at 288K is in vapor phase
with the polytropic solution with phase equilibria starting from 288K @ 10 Bar.a we get as tout = 393K

at 272.47K 10Bar.a the mixture shows a liquid fraction = 0.1
with the polytropic solution with phase equilibria starting from 272.46K @ 10 Bar.a we get as tout = 337.5K

if we compare the values of tout-tin we get 105K in the first case (all gas) and 65.04K in the second case (with 10% liquid molar fraction at inlet condition)
a quite large difference.

----------


## pbel

thank you for the update cmarc,
very useful information !

----------


## bmat

I noticed that version 1.19b of Prode Properties does include a Excel page nozzle.xls which allows to compare HEM (Homogeneous Equilibrium) with different HNE (Homogeneous Non Equilibrium) models,
in short, the differences are mainly in the range 0-0.15 of vapor mass quality
where HNE can predict values for critical flow in excess of 200-300% over HEM

----------


## carlo.stenali

Some interesting points of discussion in this thread

'http://eng-tips.com/viewthread.cfm?qid=332483'

in my opinion it is not easy to decide whether to select accuracy (HNE) or conservative and safe design (HEM)
some european manufacturers are proposing HNE-DS  and that could give (as said)  different (reduced) sizes
Prode Properties manual gives the procedure to compare the two methods
'http://www.prode.com/doc/pppman.pdf'

----------


## dbert

I am calculating the speed of sound with Prode Properties for different fractions of water and steam at 10 Bar.a

with IAPWS 1995 model which is supposed to be very accurate,
the calc's are done in Excel, 
in a cell I put the macro 

=StrMSS(1)

which returns the speed of sound for vapor, liquid and vapor + liquid mixtures

for water at 453 K 10 Bar.a Prode Properties calculates 1392 m/s

for water (0.999 fraction) + steam (0.001 fraction) at 453.028 K 10 Bar.a Prode Properties calculates 9.73 m/s

for water (0.001 fraction) + steam (0.999 fraction) at 453.028 K 10 Bar.a Prode Properties calculates 470.55 m/s

for steam at 453.5 K 10 Bar.a Prode Properties calculates 501.58 m/s

I am surprised to see those very low values (9.73 m/s) for low values of vapor mass fraction,
I have some tabulated data which confirm the trend but still I am unable to understand the origin of phenomena, could you give some explanations?

----------


## carlo.stenali

dbert,
I am not sure that a theory explaining the phenomena has been universally accepted,
I have read that for small void fractions there is bubbly flow, 
in that regime (with a uniform distribution of spherical bubbles) acoustic and kinematic perturbations are absorbed by bubbles,


may be there are other theories to explain the reduced speed of sound under these conditions.See More: Excel library for process calc's including distillation

----------


## dbert

thanks Carlo,
indeed I have read several papers discussing this phenomena and any author seems to support a different theory :-))
also I have found only a few  experimantal measurements for the speed of sound in two phase flow

----------


## carlo.stenali

I would suggest the paper "Sound Speed in Liquid-Gas Mixtures : Water-Air and Water-Steam" author Susan Werner Kieffer, 
among the different mixtures considered there is water-air, where the addition of small volume fractions of air causes a dramatic lowering of the speed of sound by nearly three orders of magnitude...

----------


## asanter

I wish to calculate a vapor-liquid-liquid phase envelope,
there is a mixture originating two liquid phases in certain conditions which I wish to investigate,
can I calculate a three phase envelope with Prode Properties?
I see in the operating manual that both three phase and multi phase envelope are included (in extended versions)

----------


## matrenel

asanter,
with Prode Properties you can calculate 
-Vapor-Liquid phase envelope
-Vapor-Liquid-Liquid phase envelope
-Vapor-Liquid-Solid phase envelope
these are not available in base versions, you should contact Prode to obtain the extension.
I utilize the Vapor-Liquid-Liquid phase envelope for Hydrocarbons+Water, in this case water forms a separate phase and we get three different lines, a dew point line (water) and vapor-liquid-liquid
Hoping this helps.

----------


## carlo.stenali

asanter,
as matrenel said with Prode Properties you can draw
vapor-liquid; vapor-liquid-liquid, and vapor-liquid-solid T-P phase diagrams (phase envelope),
by the way if you work with Excel you can easily include additional properties as enthalpy , entropy etc. with some VBA code,
Prode Properties allows direct access to a large number of properties which you can include in graph

----------


## asanter

thanks matrenel and carlo.stenali,
I have been in contact with Prode to get the extension and I can now draw a vapor-liquid-liquid phase envelope in Excel,
as commented by matrenel I need this feature for mixtures with Hydrocarbons+Water,
the standard vapor-liquid phase envelope doesn't work well with high amounts of water (not a frequent condition but...)

----------


## rense

I am calculating vapor-solid equilibria with Prode Properties, 
we have a hydrocarbon's mixture with about 6.4% CO2,
which is in your opinion the best model to select for gas (and solid) fugacity,
Soave Redlich Kwong, Peng Robinson or...

----------


## rense

I am calculating vapor-solid equilibria with Prode Properties, 
we have a hydrocarbon's mixture with about 6.4% CO2,
which is in your opinion the best model to select for gas (and solid) fugacity,
Soave Redlich Kwong, Peng Robinson or...

----------


## carlo.stenali

you should get quite equivalent results with both Soave-Redlich-Kwong and Peng-Robinson equations of state.
There have been many discussions about which is the best model, 
I think it depends from the field of application,
some authors give criteria for selection, 
for example for hydrocarbons with acentric factors < 0.3 Soave Redlich Kwong is suggested,
however this is true for standard alpha correlation,
with the extended version available in Prode Properties (with parameters regressed to fit vapor pressure, enthalpy and liquid density of pure components) you should get quite equivalent results.

----------


## rense

carlo.stenali,
is the criteria based on acentric factor (when < 0.3 Soave Redlich Kwong is suggested)  related to the average value of acentric factor of the mixture ?

----------


## carlo.stenali

rense,
this criteria allows  to decide which model to apply for (gas or liquid) fugacity,
it is based on comparative analysis of original alpha correlations which are

0.48+1.574*w-0.176*w*w (Soave)
0.37464+1.54226*w-0.26992*w*w (Peng Robinson)

these values have been regressed from different data sets

----------


## rense

thank you Carlo,


which is the formulation used for extended correlations in Prode Properties?See More: Excel library for process calc's including distillation

----------


## carlo.stenali

rense,
the general form of a equation of state (Soave-Redlich-Kwong or Peng-Robinson) is

P = RT/(V-b) - a/(V^2+ubV+wb^2)

(see The Properties of Gases and Liquids by Reid, Prausnitz, Poling)

in Prode Properties the parameters a and b have been calculated to fit experimental data of each pure component,
data includes vapor pressure, enthalpy and volume,
as result you obtain a much better fitting than using the original  expressions for alpha correlation,
and with non ideal fluids as water you get much lower errors,
this is a very important factor in phase equilibria and other unit operations.

----------


## mpat

I think it is of general interest  a thread from cheresources about the vapor-liquid-liquid phase envelope in Excel with Prode Properties

Question:
I wish to calculate the phase envelope for different mixtures of  hydrocarbons  + water including different line fractions,
Prode Properties has a Excel page to calculate vapor-liquid-liquid diagrams,
the page allows to print the bubble line, dew line plus a line with specified phase fraction,
with water the procedure correctly shows as bubble line a vapor-liquid-liquid equilibrium line,
plus the line with specified phase fraction and the water dew line (see attached image)
For my application I need to calculate at least three lines with specified phase fractions,
say 0.25 , 0.5, 0.75
how should I proceed ? 
**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]
Answer by Marchem :
differently from other simulators Prode integrates directly with Excel or Matlab,
you have access to all the methods in the library and can modify almost everything by program,
this gives great flexibility and I really appreciate this feature,

in the specific if you look inside the Excel page, VBA code you'll find
this little piece of code

' Original VBA code (prints one line with specified phase fraction)
nrpt = PFLine(stream, 1, pf, pt(0), pp(0), 51)
' nrpt is the effective number of calculated points
ri = 15
For i = 0 To nrpt - 1
      Cells(ri + i, ci) = pt(i)
      Cells(ri + i, ci + 1) = pp(i)
Next i

here the code calls the method PFLine in the library for calculating the line with specified state and phase fraction
the remaining stuff is the code to write on Excel Cells

you can easily modify this code for including more than one line with specified state and phase fraction

' Modified VBA code (prints three lines with 0.25,0.5,0.75 liq. molar fractions)
pf = 0
For ii = 0 To 2
  pf = pf + 0.25
  nrpt = PFLine(stream, 1, pf, pt(0), pp(0), 51)
  ' nrpt is the effective number of calculated points
  ri = 15
  For i = 0 To nrpt - 1
      Cells(ri + i, ci + 2 * ii) = pt(i)
      Cells(ri + i, ci + 2 * ii + 1) = pp(i)
  Next i
Next ii

I have added the first For (For ii = 0 To 2) to calculate three lines as you wish,
very simple.

Remember to define properly the settings (see the operating manual) ,
these are available under the Tab Models in Properties Editor,
for example you may decide to
-print vapor-liquid; vapor-liquid-liquid; vapor-liquid-solid diagrams
-print all calculated points or stop when crossing dew or bubble lines (default)
-validate points (default) or not etc.

remember that a phase diagram is complex  to calculate and may take a lot of time to complete if you add many lines,
you may test different possibilities as for example print all calculated points to see how the phase diagram appears before to  customize on your needs. 

Prode exposes several methods which you can access from Excel or Matlab,
these are discussed in paragraph  "Methods for calculating equilibrium lines in phase diagrams" in Operating Manual,

herebelow the description of PFLine
integer nrpt = PFLine(integer stream,double pf, double *P, double *T, int maxpt)
Given a stream, a state, a specified phase fraction and two arrays (0-maxpt elements) the procedure returns nrpt < maxpt
equilibrium points in specified phase fraction line

the above is C/C++ syntax but you can use different languages as VBA, C#, VB-Net, FORTRAN etc.

----------


## carlo.stenali

mpat,
thanks for the information,
the utility to calculate vapor-liquid-liquid phase envelope / phase diagram has been included in Prode since the origin,
a interesting point is that you can calculate vapor-liquid-liquid equilibria for many mixtures,
it's not limited to hydrocarbons plus water...

----------


## tinom

thanks,
with Prode Properties can I print a phase envelope with hydrocarbon's bubble point, hydrocarbon's dew point, water dew point and hydrate formation line ?
This could be useful for us, our simulator doesn't do that.

----------


## carlo.stenali

yes, 
you can include gas hydrate formation conditions in phase diagram,

see the paragraph Methods for Hydrate Phase Equilibria in Prode Properties Operating Manual,

there is a method HPFORM() which allows to calculate a series of equilibrium points,

the method HPFORM() gives three options for hydrate equilibria

1) assume free water present
2) calculate the amount of water present
3) solve as multiphase equilibria including solids as ice

the last gives the most accurate analysis

----------


## STD manager

Hi
if you want to buy any standard document and do not pay much money
please contact to:
i n t e r n a t i o n a l s t a n d a r d 2 0 1  2 @ g m a i l . c o m
h  t   t   p  :  /  /       internationalstandard.blog.     com

----------


## cstaff

I am doing LLE data regression with Prode Properties,
for a specific binary the procedure calculates very different values for  NRTL depending from the data set which I enter,
how could I select the best values ?

----------


## dbert

>I am doing LLE data regression with Prode Properties,
>for a specific binary the procedure calculates very different values for NRTL depending from the data set which I enter,
>how could I select the best values ? 

with Prode Properties you can do multiple vapor-liquid, liquid-liquid and solid-liquid data regression and select the best parameters based on calculated errors,
-go on BIPs dialog (see attached image) and select the binary (in the example Water-Ammonia)
go on Regress dialog (see attached image) select model (in the example Peng-Robinson NRTL with Wong-Sandler mi&#236;xing rules) , enter the VLE/LLE/SLE data (or ask the procedure to estimate VLE with UNIFAC) and calculate parameters
-in the output grid notice the data fitting errors, you can easily calculate different datat sets and select that with best match

does this answers your question ?

----------


## cstaff

thanks dbert,
I have several data sets from DECHEMA,
Prode Properties Data Regression Procedure calculates the parameters for the NRTL model in all cases, 
however the calculate values are different for the different data sets,
the reported errors (for X and Y compositions) also are different,
should I select the data set which gives the lowest errors ?

----------


## dbert

that's a quite common problem in VLE/LLE data regression,
generally I create a data set with different data sets to cover a suitable range of pressures (or temperatures),
the main problem when regressing parameters for a model is to have something which extrapolates nicely when required,
you can verify the results (at different conditions) with a TPXY diagram (there is an Excel page distributed with Prode Properties which does that) .

----------


## cstaff

thanks dbert,
yes , my problem is to evaluate how NRTL works outside the area where the parameters have been regressed,
I think the TPXY diagram is the tool that I need.

----------


## stawad

thank you all for the contributes !
I have a  question concerning water dew point in hydrocarbons as calculated with Prode Properties,
Prode shows a water dew point line (when there is free water) or a three phase curve (when condensate includes water + hydrocarbons), 


can I presume that in other cases water is contained in vapor phase (i.e. no free water) ?See More: Excel library for process calc's including distillation

----------


## carlo.stenali

yes,
Prode Properties calculates the three phase lines which are the equilibrium lines where water (or hydrocarbons) begin to condense or vaporize,
see the attached image for a typical Water + Hydrocarbons phase diagram,
there are two three phase lines, the first (on the left) is the bubble line where hydrocarbons + water are all liquid, the second line is where the water begins to vaporize.

----------


## stawad

thanks Carlo,
I have several natural gas streams with different amounts of water,
I need to identify where water begins to condensate,
the vapor-liquid-solid phase envelope utility available in Prode Properties is really useful for that,
I understand that at dew point line all water is in vapor phase,
and at buuble line water, hydrocarbons and inhibitors are all in liquid phase,
with a isothermal flash at a three phase line condition I get different compostions of water and inhibitors,
which  should indicate a incipient composition, is this correct  ?

----------


## carlo.stenali

for water-hydrocarbons equilibria (Vapor-liquid-liquid phase envelope or phase diagram) you may observe several cases:

a) values for water dew point temperature above the values of hydrocarbons dew point,
there is a separate water dew point line, below water dew point line there is liquid water (free water)

b) values for water dew point temperature below the values of hydrocarbons dew point, 
there is a three phase line indicating the point where water begin to condense

c) values for water dew point temperature below and above the values of hydrocarbons dew point, 
there is a three phase line where water (or hydrocarbons) begin to condensate

you can easily create the different cases with Prode Properties utility for generating the vapor-liquid-liquid phase envelope, 
just define a mixture of hydrocarbons, then add different amounts of water

----------


## psensel

Carlo,
can I utilize the vapor-liquid-liquid and vapor-liquid-solid phase envelope utility available in Prode Properties
to generate diagrams for non-hydrocarbons as methanol, ammonia et c.
That would be very useful for me.

for water-hydrocarbons equilibria (Vapor-liquid-liquid phase envelope or phase diagram) you may observe several cases:

a) values for water dew point temperature above the values of hydrocarbons dew point,
there is a separate water dew point line, below water dew point line there is liquid water (free water)

b) values for water dew point temperature below the values of hydrocarbons dew point,
there is a three phase line indicating the point where water begin to condense

c) values for water dew point temperature below and above the values of hydrocarbons dew point,
there is a three phase line where water (or hydrocarbons) begin to condensate

you can easily create the different cases with Prode Properties utility for generating the vapor-liquid-liquid phase envelope,
just define a mixture of hydrocarbons, then add different amounts of water

----------


## carlo.stenali

yes, you can utilize the vapor-liquid-liquid and vapor-liquid-solid phase envelope utility available in Prode Properties to generate phase diagrams of any mixture,
please note that results will depend from the thermodynamic model which you will select,
for non-hydrocarbons you may consider models as
NRTL with Wong-Sandler mixing rules
UNIQUAC with Wong-Sandler mixing rules
Wilson with Wong-Sandler mixing rules
NRTL with Huron Vidal mixing rules
UNIQUAC with  Huron Vidal  mixing rules
Wilson with  Huron Vidal  mixing rules
I have not tested the phase envelope utility with models for electrolytes and I cannot give a comment,
for all other models which I have tested it works fine in Excel 2003, Excel 2007 and Excel 2010 (my version),
also it works in matlab,
you can easily expand the feature (if requested) information is provided in this thread

Carlo,
can I utilize the vapor-liquid-liquid and vapor-liquid-solid phase envelope utility available in Prode Properties
to generate diagrams for non-hydrocarbons as methanol, ammonia et c.
That would be very useful for me.

for water-hydrocarbons equilibria (Vapor-liquid-liquid phase envelope or phase diagram) you may observe several cases:

a) values for water dew point temperature above the values of hydrocarbons dew point,
there is a separate water dew point line, below water dew point line there is liquid water (free water)

b) values for water dew point temperature below the values of hydrocarbons dew point,
there is a three phase line indicating the point where water begin to condense

c) values for water dew point temperature below and above the values of hydrocarbons dew point,
there is a three phase line where water (or hydrocarbons) begin to condensate

you can easily create the different cases with Prode Properties utility for generating the vapor-liquid-liquid phase envelope,
just define a mixture of hydrocarbons, then add different amounts of water

----------


## psensel

thanks Carlo,
Patrick

yes, you can utilize the vapor-liquid-liquid and vapor-liquid-solid phase envelope utility available in Prode Properties to generate phase diagrams of any mixture,
please note that results will depend from the thermodynamic model which you will select,
for non-hydrocarbons you may consider models as
NRTL with Wong-Sandler mixing rules
UNIQUAC with Wong-Sandler mixing rules
Wilson with Wong-Sandler mixing rules
NRTL with Huron Vidal mixing rules
UNIQUAC with Huron Vidal mixing rules
Wilson with Huron Vidal mixing rules
I have not tested the phase envelope utility with models for electrolytes and I cannot give a comment,
for all other models which I have tested it works fine in Excel 2003, Excel 2007 and Excel 2010 (my version),
also it works in matlab,
you can easily expand the feature (if requested) information is provided in this thread

Carlo,
can I utilize the vapor-liquid-liquid and vapor-liquid-solid phase envelope utility available in Prode Properties
to generate diagrams for non-hydrocarbons as methanol, ammonia et c.
That would be very useful for me.

for water-hydrocarbons equilibria (Vapor-liquid-liquid phase envelope or phase diagram) you may observe several cases:

a) values for water dew point temperature above the values of hydrocarbons dew point,
there is a separate water dew point line, below water dew point line there is liquid water (free water)

b) values for water dew point temperature below the values of hydrocarbons dew point,
there is a three phase line indicating the point where water begin to condense

c) values for water dew point temperature below and above the values of hydrocarbons dew point,
there is a three phase line where water (or hydrocarbons) begin to condensate

you can easily create the different cases with Prode Properties utility for generating the vapor-liquid-liquid phase envelope,
just define a mixture of hydrocarbons, then add different amounts of water

----------


## matrenel

thanks all for the news !
I read regularly this thread,
very interesting

----------


## carlo.stenali

for vapor-liquid-liquid phase envelope the selection of a suitable model for gas and liquid fugacities is the most important factor,
you may get very different results selecting different models.

----------


## Crob

I need to characterize petroleum components,
the manual says that Prode Properties includes a module for characterization of petrleum fractions,
can I enter a ASTM curve ?

----------


## hans23

Hi Crob,
make sure to have the module for characterizing petroleum fractions activated in your Prode Properties license,
with this module you can enter distillation curves (ASTM, TBP etc.) as well as densities, viscosities etc.

----------


## hans23

Hi Crob,
make sure to have the module for characterizing petroleum fractions activated in your Prode Properties license,
with this module you can enter distillation curves (ASTM, TBP etc.) as well as densities, viscosities etc.

----------


## dbert

Crob,


in Prode Properties the module for characterizing petroleum fractions allows to enter data from

- ASTM, TBP curves

-liquid density

-liquid viscosity

there are several procedures which you can select for best fittingSee More: Excel library for process calc's including distillation

----------


## Crob

>in Prode Properties the module for characterizing petroleum fractions allows to enter data from
>- ASTM, TBP curves
>-liquid density
>-liquid viscosity
>there are several procedures which you can select for best fitting 

thanks dbert,
I have some light components (from laboratory analysis) +  TBP curve + liquid densities, 
I see that Prode has different options, 
do these options modify the procedure  to enter the light components (C1-C4) ?

----------


## psensel

thanks dbert,
here there are some comments concerning the characterization of petroleum fractions,
-light components can be defined and the procedure automatically includes them in the list
-you can enter TBP or ASTM curves (TBP may require some pre-processing but usually gives better values)
-liquid densities should be defined, differently minimizer may fail to find a complete list of real or pseudo components

----------


## abarre

thanks all for helping us !!!

I have some questions about vapor-liquid-liquid phase envelope,
specifically,

P-H (pressure enthalpy diagrams)

P-S (pressure entropy diagrams)

P-V (pressure volume diagrams)

my question is : how can I obtain the equivalent

T-H (temperature enthalpy diagrams)

T-S (temperature entropy diagrams)

T-V (temperature volume diagrams)

thanks

----------


## carlo.stenali

you can easily convert the PH graph to a TH graph (or add a new graph if you prefer)
follow these steps :

1) in Microsoft Excel edit the data series (input data for each line)
2) modify the series y values from P values to t values

in that way you can create 
T-H
T-S
T-V
H-S (enthalpy-entropy)
H-V (enthalpy-volume)
etc...

----------


## tinom

thanks Carlo,
does Properties allow to graph multiphase (liquid-liquid) fractions ?


>you can easily convert the PH graph to a TH graph (or add a new graph if you prefer)
f>ollow these steps :

>1) in Microsoft Excel edit the data series (input data for each line)
>2) modify the series y values from P values to t values
>
>in that way you can create
>T-H
>T-S
>T-V
>H-S (enthalpy-entropy)
>H-V (enthalpy-volume)
>etc...

----------


## carlo.stenali

>does Properties allow to graph multiphase (liquid-liquid) fractions ?

yes,
you can graph 
vapor-liquid equilibria lines
vapor-liquid-liquid equilibria lines
liquid-vapor-lqiuid equilibria lines
vapor-solid equilibria lines
liquid-solid equilibria lines

----------


## tinom

thanks Carlo,
what model do you suggest to calculate the speed of sound in gas+liquid phases for a mixture of hydrocarbons (C1 = 0.7, C2 = 0.12 ...) plus CO2 and H2S ?

----------


## carlo.stenali

>what model do you suggest to calculate the speed of sound in gas+liquid phases for a mixture of hydrocarbons >(C1 = 0.7, C2 = 0.12 ...) plus CO2 and H2S ?

there are several models as EOS (SRK, PR etc.) which are good for mixtures of hydrocarbons + CO2 and H2S

with Prode Properties the methods which calculates the speed of sound for gas, liquid and gas+liquid are

ss = StrMSS(stream)
given a stream returns the speed of sound for gas, liquid and gas + liquid (for gas + liquid with HEM model)

ss = EStrMSS(stream,t,p)
given the stream pressure and temperature solves a isothermal flash at p,t and returns the speed of sound for gas, liquid and gas + liquid (for gas + liquid with HEM model)

these methods are available in Microsoft Excel as Macros,
for calculating the speed of sound for a gas + liquid mixture follow these steps

1) define the stream composition, models and BIPs (see attached images StreamComp.jpg StreamModel.jpg StreamBIPS.jpg)

2) in a cell put the macro =EStrMSS(1,$B1,$B2) which instructs Excel to calculate the speed of sound at specified temperature and pressure (see attached image SpeedofSoundinExcel.jpg)

3) modify the temperature and pressure and Excel will recalculate automatically the speed of sound for gas, liquid or gas + liquid phases

----------


## tinom

thanks Carlo,
indeed I have used Soave Redlich Kwong and Peng Robinson with good results,

could you give some information about HEM model ?
How does it work ?

>there are several models as EOS (SRK, PR etc.) which are good for mixtures of hydrocarbons + CO2 and H2S
>
>with Prode Properties the methods which calculates the speed of sound for gas, liquid and gas+liquid are
>
>ss = StrMSS(stream)
>given a stream returns the speed of sound for gas, liquid and gas + liquid (for gas + liquid with HEM model)
>
>ss = EStrMSS(stream,t,p)
>given the stream pressure and temperature solves a isothermal flash at p,t and returns the speed of sound for gas, liquid and gas + liquid (for gas + liquid >with HEM model)
>
>these methods are available in Microsoft Excel as Macros,
>for calculating the speed of sound for a gas + liquid mixture follow these steps
>
>1) define the stream composition, models and BIPs (see attached images StreamComp.jpg StreamModel.jpg StreamBIPS.jpg)
>
>2) in a cell put the macro =EStrMSS(1,$B1,$B2) which instructs Excel to calculate the speed of sound at specified temperature and pressure (see attached >image SpeedofSoundinExcel.jpg)
>
>3) modify the temperature and pressure and Excel will recalculate automatically the speed of sound for gas, liquid or gas + liquid phases

----------


## carlo.stenali

You may find some information about HEM and HNE models in this blog entry

'http://www.egpet.net/vb/entries/82302-Comparison-of-Homogeneous-equilibrium-%28HEM%29-VS-NON-equilibrium-%28HNE%29-models'

for the results of HEM vs. HNE see the attached image

----------


## cstaff

thanks for keeping us informed about the features of this product !!!

I have a question about HEM and HNE models for PSV sizing/rating,
do these models work for non-critical flows ? 
(I mean a flow where the maximum speed is below critical flow)
It may seem a stupid question but I have to size some PSV with Pset = 5 Bar.a and Pdischarge (flare network, dynamic) = 2 Bar.a

----------


## carlo.stenali

>I have a question about HEM and HNE models for PSV sizing/rating,
>do these models work for non-critical flows ?
>(I mean a flow where the maximum speed is below critical flow)
>It may seem a stupid question but I have to size some PSV with 
>Pset = 5 Bar.a and Pdischarge (flare network, dynamic) = 2 Bar.a 

when PSV outlet pressure > Pin / 2 
flow can become subcritical, the method ISPF() in Prode Properties gives reasonable results also in this are within certain limits,


you may find a discussion in this blog entry

'http://www.egpet.net/vb/entries/82303-PSV-sizing-with-HEM-%28Homogeneous-Equilibrium-Model%29-limits-of-application'See More: Excel library for process calc's including distillation

----------


## cstaff

thanks Carlo,
very useful comment !
I have found a note about using the Constant Volume Flash operation of Prode Properties for estimating the initial condition in the vessel when PSV opens,
could you provide some details?

>when PSV outlet pressure > Pin / 2
>flow can become subcritical, the method ISPF() in Prode Properties gives reasonable results also in this are within certain limits,
>you may find a discussion in this blog entry
>
>'http://www.egpet.net/vb/entries/82303-PSV-sizing-with-HEM-%28Homogeneous-Equilibrium-Model%29-limits-of-application'

----------


## cstaff

thanks Carlo,
very useful comment !
I have found a note about using the Constant Volume Flash operation for estimating the initial condition in the vessel when PSV opens,
could you provide some details?

>when PSV outlet pressure > Pin / 2
>flow can become subcritical, the method ISPF() in Prode Properties gives reasonable results also in this are within certain limits,
>you may find a discussion in this blog entry
.....

----------


## davidbottassi

Thank you very much!
Very useful!!!!

----------


## carlo.stenali

>I have found a note about using the Constant Volume Flash operation for estimating the initial >condition in the vessel when PSV opens,
>could you provide some details?

you can calculate the fluid temperature and phase equilibria with a flash operation where you specify the volume and pressure,
see this blog entry

'http://www.egpet.net/vb/entries/82307-Calculate-fluid-temperature-and-phase-equilibria-when-a-PSV-opens'

----------


## cstaff

thanks Carlo,
the procedure for calculating the conditions when the pressure safety valve (PSV) begins to discharge is useful to decide whether a specific depressurization system is required,
that is a important point as per API requirements,
does the procedure for simulating the depressurization system in Pro de Properties allow to specify the heat absorbed / exchanged by vessel ?

----------


## carlo.stenali

cstaff, 
yes, the procedure to simulate the vessel depressurization in Prode Properties allows to specify the heat exchanged as well other details as mass etc.
I will provide a short description in a new post.

----------


## tmander

the procedure for vessel depressurization in Pr ode Properties calculates both fire case and blow down with specified amount of heat exchanged (i.e. with air)

----------


## matrenel

I have a old version,
however, as said by others,  the procedure appears to be capable to simulate both PSV and BDV operations.

----------


## cstaff

thanks all,
I wish to simulate a fire case (Blowdown) with Prode Properties,
actually we do this with a different software which is *very* expensive,
hence our interest for this specific application.

----------


## tmander

I see the point :-))
actually we use Prode Properties in both small and large projects, 
Prode resides in our company server so that data is available to everyone working on a project,
we have developed std. forms and procedures (in Excel) and Office.

----------


## Rzlisk

It's useful one. Thank you

----------


## cstaff

thanks tmander,


is that a cloud or local network ?See More: Excel library for process calc's including distillation

----------


## tmander

actually we have Prode Properties installed on a local server,
we have developed std. input forms for solving a range of problems as
-vapor-liquid or liquid-liquid separator sizing/rating
-PSV sizing/rating
-blowdown simulation
-pipeline sizing / rating
-compressor simulation
-other procedures are under development

I think it should be possible to install the Prode Properties library on a web server,
however that is not (at present) our case.

----------


## cstaff

thanks,
it seems a interesting application,
are you storing in a database (SQL) or Prode Properties files ?

----------


## asanter

this thread interests me, too.
Actually we have PRODE PROPERTIES on (3) stand alone computers but we plan to move to a network application.

----------


## hans23

I have PRODE PROPERTIES 64 bits working with EXCEL 2010 and Windows 7,
also I have MATLAB (working with PRODE PROPERTIES),
when moving from 32 to 64 bit Windows 7 I decided to update all the software so I have not many problems to report,
I would suggest the same to avoid conflicts (32 vs. 64 bit versions of the library)

----------


## dbert

"when moving from 32 to 64 bit Windows 7 I decided to update all the software so I have not many problems to report"

indeed, when possible, that is a good practice,
unfortunately working with 32 and 64 bit applications I have to manage both 32 and 64 bits versions of Prode Properties :-(

----------


## carlo.stenali

we have PRODE PROPERTIES 64 bits,
according my tests the speed is about twice the 32 bits version.

----------


## mpor

I have to size several PSV for two phase flow case,
procedure is based on HEM (the isentropic nozzle model included in PRODE PROPERTIES),
my question is about discharging piping,
I have calculated (with PRODE PROPERTIES) the critical speed for gas+liquid in discharging line,
my problem is that in discharging line I have values about 50% of calculated speed of sound, could that be a problem ?
Should that mean that we have to redesign the piping ? 
Could you advise ?

----------


## carlo.stenali

with those speeds and densities you may go into troubles,
have you verified energy values in critical sections as elbows etc.?
Std. practice is to keep match number in main header below 0.5
but this is a general indication (must be verified for specific cases as said)

----------


## mpor

thanks,
could you suggest a criteria to calculate maximum stress in lines when a PSV discharges ?
Is the criteria to limit match number in main header below 0.5 based on maximum allowable stress  on piping ?

----------


## rense

mpor,
perhaps you have noticed the answer by Carlo on another group, I paste here for interested readers

while a value of 0.5 may be acceptable (that depends from several factors as density etc.)
you may evaluate F on a determined section of piping as

F = p*area + dens*area*v*v/g

as you see there is a static component (p*area)
and a dynamic component (dens*area*v*v/g)

from this you can calculate the stress. 

To what said by Carlo I would add that API std. is a good source of information about this topic.

----------


## mpor

thanks rense

"perhaps you have noticed the answer by Carlo on another group, I paste here for interested readers

while a value of 0.5 may be acceptable (that depends from several factors as density etc.)
 you may evaluate F on a determined section of piping as

F = p*area + dens*area*v*v/g

as you see there is a static component (p*area)
 and a dynamic component (dens*area*v*v/g)

from this you can calculate the stress. 

To what said by Carlo I would add that API std. is a good source of information about this topic."

----------


## carlo.stenali

for those working with Mathcad I am pleased to inform that a free software is available from PTC

'http://communities.ptc.com/community/mathcad/chemical_engineering/blog/2013/06/01/the-prode-properties-dll-is-here'

which allows to link Mathcad with Prode Properties,


my first impression is that it's a complete and well documented addition,
comments appreciated !See More: Excel library for process calc's including distillation

----------


## abarre

thanks Carlo,
I have a old version of Mathcad,
does PRODE PROPERTIES work with Mathcad 12 ?

----------


## carlo.stenali

hi abarre,
I have Mathcad 15,
however according the link

'http://communities.ptc.com/community/mathcad/chemical_engineering/blog/2013/06/01/the-prode-properties-dll-is-here'

you should be able to link your version of Mathcad with PRODE PROPERTIES,
keep us informed !

----------


## abarre

thanks Carlo,
I have downloaded the free PTC software to link Mathcad with Prode Properties,
actually at office I have Windows 8 64 bits with Prode Properties 64 bits and Excel 64 bits,
I run Mathcad at home with a different computer based on Windows 32 bits,
I'll install tomorrow and report in case of problems.

----------


## dbert

thanks Carlo,
I have a old copy of Mathcad which I wish to test with Prode Properties :-)

----------


## mrbabu

thanks for the information,
actually I have not Mathcad but Prime,
does the software work with Prime ?

----------


## carlo.stenali

mrbabu,
you may contact developers in this forum
'http://communities.ptc.com/community/mathcad/chemical_engineering/blog/2013/06/01/the-prode-properties-dll-is-here'
hoping this helps,
Carlo

----------


## cmarc

I am utilizing the PIPE macro in Excel 64 to simulate a segment of pipeline,
I see that for two-phase flow the default model is Beggs & Brill,
does this model work well  when pipeline is not horizontal ?
(I know it works but I wish to get opinions about the range of application of Beggs & Brill)

----------


## hswang2

nice, but I didn't see any tool to downolad

----------


## carlo.stenali

Hi hswang2,
there are several versions of PRODE PROPERTIES,
a FREE VERSION (for personal, non commercial use) 
is available here

'http://www.prode.com/en/download.aspx?fname=ppp.exe'

hoping this helps.

----------


## tinom

thanks Carlo,
I would add that free version has several limits (number of chemicals in database etc.)
but does allow to solve in Excel / Matlab / Mathcad 
complex units as columns, compressors, flash operations etc.

----------


## carlo.stenali

cmarc,
you may try to find a copy of "Multiphase Flow in Wells" by Brill & Muckherjee (it's a SPE monography available in many libraries)
according my experience with hydrocarbons Beggs & Brill model is reasonably accurate in a range of operating conditions 
(i.e. something like a Peng Robinson or Soave EOS : you can use it in most cases).

----------


## cmarc

Carlo,
thanks for the information, 


I have not access to that book, could you share some information about ranges of application for Beggs & Brill model as available in PIPE object of PRODE PROPERTIES?See More: Excel library for process calc's including distillation

----------


## carlo.stenali

for pipelines Beggs & Brill is my default method for multiphase,
for wells, Beggs & Brill is accurate for inclined wells , for vertical wells you may select Orkiszewski method

----------


## cbadia

cmarc,
there is a large number of documents available showing the performances of Beggs & Brill vs. alternative methods for two phase flow,
you can safely use this model for multiphase flow on horizontal or inclined segments with water content not too high.

----------


## carlo.stenali

>cmarc wrote
>I have not access to that book, could you share some information about ranges of application for Beggs & Brill model as available in PIPE object of PRODE PROPERTIES? 

could you post some details about your application of Beggs & Brill multiphase model ?
Carlo

----------


## mrbabu

I agree with carlo.stenali,
for multiphase (HC + water)
Beggs & Brill is accurate for inclined segments , for vertical segments you may select Orkiszewski method

----------


## cmarc

thanks all for the information,
I am modeling a 5 km pipeline (multiphase HC + water 3% vol) near horizontal,
based on your comments I think Beggs & Brill is suitable for this application.

----------


## cstaff

I am modeling a wet gas compression stage with PRODE PROPERTIES,
which is the correct value for efficiency to enter ?
is that provided by manufacturer for dry gas or should I correct in some way ?
Thanks for help.

----------


## carlo.stenali

cstaff,
the point to consider here is that efficiency depends from the kind of process application, 
if there is little liquid amount perhaps you may use the same value of dry gas for those conditions 
(i.e. the value given by manufacturer or estimated for that kind of compression stage)
when the amount of liquid is high (compared top vapor phase) then in most cases you need to enter
a different value (of that for dry gas) for efficiency,
if you are simulating some specific operations as screw compressors then you may ask the manufacturer for suitable value.

----------


## Almart

thanks Carlo,
I am facing a similar problem (estimate of discharge temperature with wet gas compression satge)

----------


## cmarc

Carlo has given a good advise,
as first step you can simulate a compression stage with some predefined value for efficiency 
this allows to estimate the HP conditions, power etc.
then it's better to ask the manufacturers which (usually) include in simulation specific parameters which allow more accurate results.

----------


## tmander

PRODE extended five parameters EOS (Peng Robinson, Soave Redlich Kwong, Cubic Plus Association variants)

with release 1.2 of Base version the extended versions of Peng Robinson and Soave Redlich Kwong include five parameters for each compound (previously the five parameters were not available in base version)

have you compared the three parameters version vs. five parameters version ?
Does the five parameters version allow more accuracy on VLE / enthalpy / density values ?

----------


## hcostello

tmander, 
there is a thread at cheresources about this topic,
I have not compared the results but I think the five parameters formulation is more accurate.

----------


## carlo.stenali

yes, 
the comments are interesting and I fully agree,
specifically for that mentioning some "unusual" phase diagram generated by extended EOS versions,


I have had a similar experience but the reason was some strange values for BIPs (I presume extended EOS should use a specific set of BIPs)See More: Excel library for process calc's including distillation

----------


## mderra

I have compared gas and liquid densities calculated by PRODE extended EOS with some values from NIST, 
for several fluids as C3, C5, ammonia etc.  
differences are usually within 2-4%

----------


## carlo.stenali

mderra,
my results confirm your observations,
the differences in liquid densities are (usually) lower than 3-5% outside critical area,
in critical area differences  may be larger for mixtures,
take care to define correct BIPs (kij for EOS) 
or set BIPs to 0 for mixtures such as hydrocarbons.

----------


## cmarc

may I add custom units in PRODE PROPERTIES ?
There is the description of the methods available in documentation but I would need an example.

----------


## rense

cmarc,
you can add custom units after std. units,
to add a custom unit use the method
UMAU(k1,k2,"unit",code)
where  k1, k2 are the conversion constants (see the manual)
"unit" is the string to identify the unit as "M3/Kg" etc
code is the code for that unit

----------


## carlo.stenali

cmarc,
as suggested by rense you can add custom units in PRODE PROPERTIES,
for example to add Nm3/h (which is not included in gas flow units)
I do

k= mw * 0.00001239;
UMAU(k,0.0,"NM3/h",CONV_UM_WG)

where k is the conversion factor calculated from density at normal conditions

in the same way you can add units for SM3/h , SCF/h etc.

the main advantage with this method is that you can easily customize the interface with your own (standard and normal) units which may be different in different countries (in Europe normal and standard temperatures can change)

----------


## Danny_Harris

That's great software.......

----------


## Almart

mderra & carlo.stenali,
for liquid densities of polar fluids as water, ammonia etc.
the values predicted by Extended EOS are more accurate than Peneloux method,
however on derivatives of compressibilities (i.e. isothermal compressibility)
errors are quite large,
just to mention this.

----------


## cmarc

yes,
on derivatives of volume vs. pressure the errors are high for polar fluids,
however we do need usually absolute values (i.e. volumes, densities etc.)
not the derivatives,
for those a better model should be BWR or some related.

----------


## abarre

could you please explain how to add custom unit SM3/DAY unit for a gas flow?

----------


## carlo.stenali

abarre,
it's very easy to add new units to PRODE PROPERTIES,
you would utilize the method UMAU() to add new units,
see the description in the operating manual,

'http://www.prode.com/docs/pppman.pdf'

you need the define conversion factor, the name of the unit "SM3/Day" and the property (gas flow)

since you need a value at standard condition you can calculate the conversion factor from molar weight

UMAU(mw*1.175E-7,0,"SM3/Day",UM_WG)

where the first parameter mw*1.175E-7 defines the conversion factor
the second value is 0 as values start from 0
the third is the name for the unit
and the last is the property (gas flow), 
see the operating manual for the numeric code of each property

----------


## abarre

thanks Carlo,
nice information,
for hours instead of days should I only change the constant?

----------


## carlo.stenali

yes,


you have to change only the constant of conversion.See More: Excel library for process calc's including distillation

----------


## stawad

I wish to calculate the speed of sound for a vapor + liquid mixture,
the application would be the Mach number in a flare network,
I know that Prode Properties has a specific method for calculating the speed of sound in mixed phases,
which are the basis of that method ?

----------


## carlo.stenali

PRODE PROPERTIES calculates the speed of sound in mixed (vapor + liquid) phase
with HEM (Homogeneous Equilibrium Model)

HEM method is reliable for a large range of applications including flare networks,

note that PRODE PROPERTIES has methods to design/rate pipes / pipelines which can be utilized to simulate a flare network.

----------


## stawad

thanks Carlo,
does HEM method (as coded in PRODE PROPERTIES) assume the same or different velocities for vapor and liquid phases ?

----------


## carlo.stenali

yes,
in HEM (Homogeneous Equilibrium Model) vapor and liquid phases form a homogeneous mixture traveling at same speed,

if you wish to model a fluid forming a non-homogeneous mixture use HNE (Homogeneous Non-equilibrium Model) instead,

Carlo

----------


## acar

Carlo,
I have to calculate the speed of sound for a vapor + liquid mixture and I think to use Extended Peng Robinson Model available in PRODE PROPERTIES,
does that model give consistent results for a natural gas mixture (C1-C9 + CO2..) ?

----------


## carlo.stenali

yes,
for natural gas mixtures I would select the Extended Peng Robinson or the Extended Soave Redlich Kwong versions available in PRODE PROPERTIES,
you may also consider BWR or (when water-alcohools as methanol etc.) present the different variants of CPA.

For calculating the speed of sound the procedure needs to evaluate density, enthalpy and entropy
so when selecting the model you should consider the accuracy
given by the different models for these properties.

----------


## cbadia

Carlo,
I see that predicted speed of sound is (very) sensible to selected models for enthalpy and entropy,
what happens if I mix different models as, say,
Peng Robinson for fugacity and Lee Kesler for enthalpy ?

----------


## cbadia

Carlo,
I see that predicted speed of sound is (very) sensible to selected models for enthalpy and entropy,
what happens if I mix different models as, say,
Peng Robinson for fugacity and Lee Kesler for enthalpy ?

----------


## carlo.stenali

you can mix models if you think that a model gives better accuracy on some property,
in PRODE PROPERTIES you can define packages to include
different models for Fg,H,S,V,Visc, etc.this allows a great flexibility 
to manage mixtures with non-standard behaviour,
for hydrocarbons I usually select the extended versions (5 parameters) of 
Peng Robinson and Soave Redlich Kwong but other EOS
can be defined as well.

----------


## carlo.stenali

you can mix models if you think that a model gives better accuracy on some property,
in PRODE PROPERTIES you can define packages to include
different models for Fg,H,S,V,Visc, etc.this allows a great flexibility 
to manage mixtures with non-standard behaviour,
for hydrocarbons I usually select the extended versions (5 parameters) of 
Peng Robinson and Soave Redlich Kwong but other EOS
can be defined as well.

----------


## cbadia

thanks Carlo,
some papers suggest Lee Kesler for enthalpies of natural gas mixtures,
so I wish to compare and see the results

----------


## mderra

in my experience Lee Kesler gives indeed accurate results for HC mixtures, 


not to use for other chemicals, though.See More: Excel library for process calc's including distillation

----------


## carlo.stenali

in some cases you can select the Lee Kesler Plocker model
which has been designed to handle  very asymmetric mixtures

----------


## asanter

does someone know where to find good VLE data sets for C2-H2O, C3-H2O, H2S-H2O etc.

I wish to use PRODE PROPERTIES to regress temeperature dependent BIPs for these pairs...

----------


## dchernandezs

thanks a lot

----------


## mohammed_eldieb

where is the link??

----------


## carlo.stenali

mohammed,
look for PRODE PROPERTIES with Google
or go directly to
'http://www.prode.com/en/properties.htm'

----------


## carlo.stenali

mohammed,
look for PRODE PROPERTIES with Google
or go directly to
'http://www.prode.com/en/properties.htm'

----------


## mohammed_eldieb

thank you Carlo, got it.

----------


## matrenel

Does the distillation column in PRODE PROPERTIES allow to solve VLL (vapor-liquid-liquid) ?
I have a three phase distillation to simulate.

----------


## carlo.stenali

matrenel,
yes, the column model in PRODE PROPERTIES can solve

vapor-liquid
vapor-liquid-liquid
liquid-liquid

separations, you can specify reflux,
heat, purity, recovery etc.

----------


## cbadia

Matrenel,
yes, I have solved both VL and VLL columns with PRODE PROPERTIES,
(no direct experience with LL but that depends from my field of application)

----------


## matrenel

thanks Carlo and cbadia,
I was in contact with PRODE, a commercial licence is required for the vapor-liquid-liquid column,
actually the free version 1.2b does include only the vapor-liquid column,
I decided to upgrade and I have tested the VLL column, 
no problems to solve my specific application.

----------


## SLB

Hi friends
Hope everything goes well with you
I have provided a huge collection of newest petroleum software like: Petrel 2013.3, Eclipse 2013.1, Geoframe 2012, Paradigm 2011.3, Olga 7.2, OSP4.0.3, Mepo 4.2, Techlog 2013.2, RoXar RMS 2013.1, Ecrin 4.2.07, CMG 2013.1, S/M/T K/ingdom 8.8, Rokdoc 6.0.0.107, Desicion Space Desktop r5000.8.1.1, Drillworks 5000.8.1.1, Openworks r5000.8.1, VIP-Nexus 5000.4.4.0, Skua Gocad 2011.3, IPM 8.0, PetroMod 2013.1, Interactive Petrophysics 4.1, Openflow 2012.2, Pipesim 2013.1, Que$tor 3013Q1, FractPro 2013, Vista 13, Jason 8.4, GeoGraphix Discovery 2013, and so many other things ...
if anybody need Please contact me I will share with you. Also I need some applications hope you can kindly help me.

My E-mail is: slbsoft33@gmail.com



Cheers.See More: Excel library for process calc's including distillation

----------


## carlo.stenali

matrenel wrote
"I was in contact with PRODE, a commercial licence is required for the vapor-liquid-liquid column,
actually the free version 1.2b does include only the vapor-liquid column,
I decided to upgrade and I have tested the VLL column, no problems to solve my specific application."

thank you for your contribute,
Carlo

----------


## tinom

Carlo,
have you utilized the depressuring module for a fire case ?
Actually my licence doesn't activate the module, 
I would be interested to include it providing it calculates the fire case with vaporizing liquid in the vessel

----------


## carlo.stenali

yes, it does both fire case and the so called cold depressuring,
what do you wish to know ?,

----------


## tinom

I have to evaluate a fire case for a three phase separator (gas+liquid)
do you think I can go with depressuring module in PRODE ?

----------


## carlo.stenali

yes,
I select API formulation to estimate heat exchanged (fire case, wetted surface area).
and BDV + RO to control fluid flow,
do you have some specific request or codes to apply ?

----------


## mpat

tinom,
as said by Carlo for fire case you can estimate the heat absorbed with different methods including API (you need to define vessel's geometry)

----------


## carlo.stenali

by the way to activate the module you need to contact Prode and obtain a new lic file which includes the activation key,
as far as I know the last release of depressuring utility is may 2013

----------


## stawad

I have several control valves in two-phase service (flashing liquid)
can I use HEM model available in PRODE PROPERTIES to verify sizing ?

----------


## carlo.stenali

with PRODE PROPERTIES you have different options,
you can model a valve with a flash operation or a  predefined model as HEM or HNE,
the selection depending from the specific application,
Carlo

----------


## B.M.KANG

very helpful, thanks

----------


## pbel

for those interested to Mathcad Thermodynamic applications
including distillation this blog may be interesting,

'http://www.harveyhensley.com/blog-che-old-school-and-new-school'

Pat

----------


## pbel

for those interested to Mathcad Thermodynamic applications
including distillation this blog may be interesting,

'http://www.harveyhensley.com/blog-che-old-school-and-new-school'



PatSee More: Excel library for process calc's including distillation

----------


## bmat

thanks pbel,
I have not Mathcad but the page discussing how to optimize column operating is very interesting and I recommend reading,
by the way I was not aware of applications of contour plot method for those analysis,

----------


## carlo.stenali

I read regularly that blog,
the posts about proper design of reactors and distillation columns 
are in my opinion very interesting,
Carlo

----------


## carlo.stenali

I read regularly that blog,
the posts about proper design of reactors and distillation columns 
are in my opinion very interesting,
Carlo

----------


## ivan

Thank you

----------


## murali52

Thank you.

----------


## acar

the last posts explains how to solve different reactors with Prode Properties + Mathcad,
also it introduces a different method capable to mix many streams (base method is limited to two streams only),
interesting stuff...

----------


## carlo.stenali

I agree,
that can be useful as reactions are not supported in base version of Prode Properties,
(well, of course you can solve based on energy of formation but Mathcad simplifies the work)
Carlo

----------


## Crob

Prode Properties includes Gibbs and heat of formation in database for all components,
it's easy to solve simple reactions

----------


## cbadia

by the way you can use equivalent procedures in Excel or Matlab,
libraries in Matlab and Mathcad have probably much more numerical methods than Excel
but for simple optimization Excel has a good solver.

----------


## anakins

Thank you very much

----------


## cstaff

the release 1.2b , available for download from prode.com, includes the multiphase flash for hydrates

----------


## abarre

the hydrate model in version 1.2c is really very accurate

See More: Excel library for process calc's including distillation

----------


## mrbabu

can you give an estimate of possible errors when calculating hydrate formation conditions with Prode Properties including 20/30 % methanol ?
Thanks

----------


## carlo.stenali

there are a few values published by developer,

**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]

I have verified some of these points (ask Prode for the list), 
with simplified model for hydrate formation pressure you may expect an error in the range 3-15% (depending from structure and temperature),
errors in hydrate formation temperature are in the range 1-2 K

the complex model is more accurate,

when adding methanol as inhibitor erros are about the same (with the specific parameters provided for CPA PR Cubic Plus Association or other models, 
however I suggest to contact Prode for more accurate figures...

----------


## carlo.stenali

there are a few values published by developer,

**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]

I have verified some of these points (ask Prode for the list), 
with simplified model for hydrate formation pressure you may expect an error in the range 3-15% (depending from structure and temperature),
errors in hydrate formation temperature are in the range 1-2 K

the complex model is more accurate,

when adding methanol as inhibitor erros are about the same (with the specific parameters provided for CPA PR Cubic Plus Association or other models, 
however I suggest to contact Prode for more accurate figures...

----------


## pmdeshpande4

Dear All,
Can anybody send download link????

----------


## carlo.stenali

sure, 
go to this page for description of features and download

**[link Point to another website Only the registered members can access]
*link*




<![CDATA[[Only Registered And Activated Users Can See Links]

----------


## AHMED4002

can someone provide me a link for the download of those awesome shared files?
its keep redirecting me....
newbie in the forum although

----------


## carlo.stenali

this is the page to download Prode Properties
'http://www.prode.com/en/download.htm'
select ppp.exe and take note of password (read the page for the password)
to install follow the instructions in that page,
remember to log in as admin

----------


## Almart

can you share comments about the dynamic column model available in Prode Properties Extended ?
I understand that it allows to simulate transients keeping in account liquid and vapor hold-ups in all plates (rigorous model).

----------


## hans23

correct* 
the main difference (against steady-state model) is that it keeps in account vapor & liquid holdups*
you can solve many different problems* 
I can add that solver is robust (compared to different software) and reasonably fast*
do you have specific questions ?

----------


## mderra

Almart*
with dynamic column in Prode* it is possible to model rigorously even **BATCH COLUMNS** 

the solver is very good as reported by Hans23

----------


## asanter

have you tested Prode Properties hydrate models with salts ?
I am considering to install the electrolyte model and wish to receive comments.

----------


## cstaff

yes* tested the Pitzer model* accurate * 


consider some technical support (there are many different parameters to tune for the different cations and anions)See More: Excel library for process calc's including distillation

----------


## mrbabu

cstaff,
have you tested the batch column module in PRODE with GERG 2008 model ?
I have a previous version (not including GERG 2008 which is now available in all versions) and I am considering to update...
Thanks.

----------


## carlo.stenali

in Prode Properties you can select GERG 2008 model for the different properties (fugacity, enthalpy, entropy, volume), 
this is true for all units (compressors, pipelines, columns, including batch columns etc.)

----------


## dbert

Carlo, can you share an example of reactive flash solution with Prode Properties ? I understand there are two steps, chemical equations balance and then solving the reactive flash (as for other operations) but there is little information in operating manual,  Daniel

----------


## mabhatti

Great things are here

----------

