Excel library for process calc's including distillation

[abdullah7877]

thanks

[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 ?