Chemical Engineering February 2014 - 41

condition is equal to the square
root of γ.
4. Under adiabatic flow, specific
heat ratio has significant effect on
pressure drop, but the effect of molecular
weight is negligible.
With these conclusions in mind
and the equations derived in this
article, engineers can begin to make
educated assumptions when they
are asked to size and determine pressure
drop for pipes with compressible
fluid flow.
References
1. American Petroleum Institute, Standard
521, Pressure-relieving and Depressuring
Systems, 5th Ed., Washington D.C., 2007.
2. Yu, F.C., Compressible Fluid Pressure Drop
Calculation-Isothermal Versus Adiabatic, Hydrocarbon
Processing, pp. 89-95, May 1999.
3. Darby, Ron, " Chemical Engineering Fluid
Mechanics " , 2nd Ed., CRC, 2001.
4. Flow of Fluids Through Valves, Fittings, and
Pipe, Technical Paper No.410, Crane Co., Joliet,
Ill., 1988.
5. Saad, M.A., " Compressible Fluid Flow " , 2nd
Ed., Prentice-Hall, Englewood Cliffs, NJ, 1998.
6. Mak, H.Y., New Method Speeds PressureRelief
Manifold Design, Oil and Gas Journal,
Nov. 1978.
7. Branan, Carl R., " Rules of Thumb for Chemical
Engineers " , 4th Ed., Gulf Professional
Publishing, Burlington, Mass., 2005.
8. Lapple, C.F., " Fluid and Particle Mechanics " ,
University of Delaware, Newark, Del., 1951.
9. Walters, T., Gas-Flow Calculations: Don't
Choke, Chem. Eng., Jan. 2000.
Authors
Fucheng Teng is a process
technologist/specialist
at Jacobs Canada Inc. (205
Quarry Park Blvd. S.E.,
Calgary, Alberta, Canada
T2C3E7; Phone: +1 403-6408149,
Email: fucheng.teng@
jacobs.com). He holds a B.S.
degree in polymer material
and engineering from Dalian
University of Technology and
an M.S.Ch.E. from the Uni■
Edited by Mary Page Bailey
versity of Alberta. He has accumulated seven
years of engineering experience, including commissioning
and startup, wastewater treatment,
mineral processing and SAGD (steam-assisted
gravity drainage) facility design. Teng is a Certified
Six Sigma Green Belt (CSSGB) from the
American Society of Quality.
Pedro Medina (Phone: +1
403-692-2302; Fax: +1-403
255-1421; Email: pedro.medina@jacobs.com)
has over
seventeen years of experience
as a process engineer with
expertise in process design of
both new and retrofit projects
in the petrochemicals and oiland-gas
industries. For the
last seven years, he has been
with Jacobs Canada Inc. as a
principal process engineer. For the last five years,
he has been assigned to SAGD projects for major
bitumen production companies in Northern Alberta.
He is a professional engineer accredited
by the Association of Professional Engineers and
Geoscientists of Alberta. Medina graduated from
Simón Bolívar University in Caracas, Venezuela
where he received an M.S.Ch.E.
Mark Heigold (Phone: +1
403-258-6440, Email: mark.
heigold@jacobs.com) is a technical
design supervisor at
Jacobs Canada Inc. He holds
a B.S.Ch.E. from the University
of Calgary. He has more
than 19 years experience in
process design in the fields
of power generation, SAGD,
heavy oil, upstream gas
processing and water treatment.
Heigold is a member of the Association
of Professional Engineers and Geoscientists
of Alberta.
Flow Measurement
What is the outcome?
The End Result is Often Uncertain.
An example is when manufacturing polyurethane products.
The reaction of polyurethane components does not stop
after coming off the production line. The fi nal products are
stored and observed for several weeks. By the time faults in
the process are detected, it is too late.
KRAL fl owmeters can control the mixtures
with highest precision. Problems can be
exposed earlier in the manufacturing
process thus preventing
defective fi nished products.
KRAL AG, 6890 Lustenau, Austria, Tel.: +43 / 55 77 / 8 66 44 - 0, e-mail: kral@kral.at
KRAL - USA, Inc., Tel.: +1 / 704 / 814 - 6164, Fax: +1 / 704 / 814 - 6165, e-mail: sales@kral-usa.com
Circle 17 on p. 60 or go to adlinks.che.com/50973-17
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Chemical Engineering February 2014

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