Heat Capacity and Viscosity of Ethane/Propane Mix
Heat Capacity and Viscosity of Ethane/Propane Mix
(OP)
I am modeling a pipeline, which carries an Ethane/Propane Mix. I cannot seem to find any heat capacities or viscosities for a standar mix (80/20).
Can anyone help?
Can anyone help?





RE: Heat Capacity and Viscosity of Ethane/Propane Mix
Alternatively, you could look at 'Properties of Gases and Liquids' Reid, Prausnitz and Poling. They have methods on estimating those properties. Viscosities of mixtures though can be highly non-ideal.
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
How are you modeling the pipeline? What is your expected range of operating pressures and temperatures?
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
mixture viscosity = 0.8(C2 viscosity) + 0.2(C3 viscosity),
since your composition is 0.8 [C2] and 0.2 [C3]. The pure component viscosities can be gotten from Fig. 23-30 from the GPSA Handbook, 10th ed.
The easiest way is to use a process simulator like HYSYS, PIPEPHASE, PRO-II, Aspen, ChemCAD, etc. as TD2K said. Maybe if you have a buddy that works for an engineering contractor, you can call him up and get him to do this for free since it takes about 30 seconds to do this in PIPEPHASE...
Hope this helps!
Thanks!
Pete
P. J. (Pete) Chandler, PE
Principal Engineer
Mechanical, Piping, Thermal, Hydraulics
Processes Unlimited International, Inc.
Bakersfield, California USA
pjchandl@prou.com
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
So, Pete, how do I go about using Pipephase for this problem?
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
Check under your output options, there should be something that allows you to print out the physical properties. I haven't used Pipephase for a few years and I suspect it's changed significantly but this information will be there.
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
It's easy-greasy:
Just build a model with one source, one sink, one junction, and one foot of 24" pipe from the source to the junction and from the junction to the sink. Set the heat transfer to isothermal. All you are interested in is fluid properties so who cares about hydraulics or heat transfer.
Set the simulation type to Network and the fluid type to Compositional.
Pick your components from the tables.
Click on the source and type in your composition, P, T, and a flowrate of 1 lb/hr. Set your actual process conditions at the sink: fixed P, e.g. 120 psig, estimate the rate of 1 lb/hr, and at the source, fix the rate at 1 lb/hr and estimate the pressure at something a little higher than your fixed sink pressure, e.g. 121 psig.
Run the model and look at the flash report at the junction. The physical, thermo, and transport properties are printed therein. You're done! E.T. about 2 minutes for you, about 30 seconds for me since I do this all the time...
Thanks!
Pete
P. J. (Pete) Chandler, PE
Principal Engineer
Mechanical, Piping, Thermal, Hydraulics
Processes Unlimited International, Inc.
Bakersfield, California USA
pjchandl@prou.com
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
You also know that PipePhase can do your pipeline hydraulics for you...right? And sensitivity/case studies for different line sizes, wall thicknesses, ambient temperatures, etc. I should be a SimSci salesman... Wonder if I get a commission?
The method I outlined above is useful only for generating physical/thermo/transport properties. Pipephase is obviously MUCH more capable than just that little task. It better be, considering how much it costs! It's sort of like swatting a fly with a shotgun.
Thanks!
Pete
P. J. (Pete) Chandler, PE
Principal Engineer
Mechanical, Piping, Thermal, Hydraulics
Processes Unlimited International, Inc.
Bakersfield, California USA
pjchandl@prou.com
RE: Heat Capacity and Viscosity of Ethane/Propane Mix
Check in Perry - Handbook of chemcial Engineers. PREDICTION OF CORRELATION OF PHYSICAL PROPERTIES. From there you can calculate the viscosity.
regards,
chem55