Transcript Why n-propanol? - Department of Chemical Engineering

SPME Coupled with GCFID for the Detection of
n-Propyl Alcohol and Its
Use as a Geothermal
Tracer
Michael Mella1,2
Energy and Geoscience Institute - University of Utah,
2 Chemical Engineering Department – University of Utah
Senior Projects Lab I - 2006
1
Why n-propanol?
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Liquid phase only tracers and vapor
phase only tracers are in common use
Two-phase tracers are needed to
better trace water
n-Propanol has a similar partition
coefficient to water, similar two-phase
characteristics to water
Objectives
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Lab work - Develop an analytical
method to reduce the limit of
detection of n-propanol
Field work - Validate method with a
field test
Lab Development
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Solid Phase MicroExtraction (SPME)
was used to help lower the limit of
detection over previous methods by 30
fold
Gas Chromatography with a Flame
Ionization Detector used to analyze npropanol solutions
SPME basics
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A flexible fiber coated with 85µm thick
Carboxen/PDMS layer
A needle that houses the fiber and an
injection assembly
GC analysis
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Needle injected into 300°C GC inlet
Separation by HP-5 capillary column
Detection by FID
Analysis of signal using HP-CHEM
software
Analytical method results
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Limit of detection at 1 ppb
Reduction by a factor of 30 from
previous methods
Lower limit of detection means less npropanol needed for test
Method can be extended to other
alcohols and aldehydes
Objectives

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Lab work - Develop an analytical
method to reduce the limit of
detection of n-propanol
Field work - Validate method with
a field test
Field test
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Injector 34-9RD2 of Coso East Flank
tagged with 165 gallons n-propanol
Samples taken from surrounding East
Flank producers
Field Work
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Alcohol returns
Comparison with a liquid tracer test
Alcohol returns
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Raw results
E(t) scaled results and recovery
Liquid phase tracer results
34-9RD2 Propanol
100
90
38C-9 propanol in steam
80
38C-9 propanol in brine
70
38D-9 propanol in steam
ppb
60
38D-9 propanol in steam
50
40
30
20
10
0
0
10
20
days
30
40
50
60
70
Alcohol returns
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Raw results
E(t) scaled results and recovery
Liquid phase tracer results
E(t)
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E(t) residence-time distribution function
E(t) is a way to normalize for mass of tracer
injected and flow rates
E(t) required for future assessment of
return data, an example is the convolution
integral and tracer recovery
E (t ) 
C (t )

 C (t ) dt
0
Tracer Recovery
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Use E(t) to calculate the amount of tracer
recovered in both the liquid phase and the
vapor phase.
t
%returned   E (t )dt
0
Normalized n-propanol return
0.003
38C-9 propanol in steam
38C-9 propanol in brine
38D-9 propanol in steam
38D-9 propanol in brine
0.0025
E(1/day)
0.002
0.0015
0.001
0.0005
0
0
10
20
30
days
40
50
Alcohol returns
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Raw results
E(t) scaled results and recovery
Liquid phase tracer return
Liquid phase tracer return
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2 months prior 100 kg 1,3,5-NTS
injected into 34-9RD2
Samples from the same area were
taken and analyzed by HPLC with a
fluorescence detector
1,3,5-NTS Return
50
45
40
38A-9
38B-9
38C-9
38D-9
35
ppb
30
25
20
15
10
5
0
0.00
50.00
100.00
days
150.00
Return comparisons
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Normalized n-propanol and 1,3,5-NTS
return curves were plotted together
with a common x-axis of days after
their respective injection date.
Normalized tracer returns
0.01
0.009
38C-9 propanol in
38C-9 propanol in
38D-9 propanol in
38D-9 propanol in
38C-9 1,3,5-NTS
38D-9 1,3,5-NTS
0.008
0.007
E(1/day)
0.006
steam
brine
steam
brine
0.005
0.004
0.003
0.002
0.001
0
0
50
100
days
150
Return comparisons
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Tracer recovery of n-propanol = 3.5%
Tracer recover of 1,3,5-NTS = 74.8%
Conclusions
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Similar arrival times for 1,3,5-NTS
and n-propanol in well 38C-9
Appearance of n-propanol in 38D-9
but not 1,3,5-NTS
38B-9 seems to have been “skipped”
by both tracers
Less return of n-propanol than of
1,3,5-NTS
Normalized tracer returns
0.003
38C-9 propanol in
38C-9 propanol in
38D-9 propanol in
38D-9 propanol in
38C-9 1,3,5-NTS
38D-9 1,3,5-NTS
0.0025
E(1/day)
0.002
steam
brine
steam
brine
0.0015
0.001
0.0005
0
0
2
4
6
8
days
10
12
14
Conclusions
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Similar arrival times for 1,3,5-NTS and
n-propanol in well 38C-9
Appearance of n-propanol in 38D9 but not 1,3,5-NTS
38B-9 seems to have been “skipped”
by both tracers
Less return of n-propanol than of
1,3,5-NTS
Normalized tracer returns
0.01
0.009
38C-9 propanol in
38C-9 propanol in
38D-9 propanol in
38D-9 propanol in
38C-9 1,3,5-NTS
38D-9 1,3,5-NTS
0.008
0.007
E(1/day)
0.006
steam
brine
steam
brine
0.005
0.004
0.003
0.002
0.001
0
0
50
100
days
150
Conclusions
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Similar arrival times for 1,3,5-NTS and
n-propanol in well 38C-9
Appearance of n-propanol in 38D-9
but not 1,3,5-NTS
38B-9 seems to have been
“skipped” by both tracers
Less return of n-propanol than of
1,3,5-NTS
Conclusions
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Similar arrival times for 1,3,5-NTS and
n-propanol in well 38C-9
Appearance of n-propanol in 38D-9
but not 1,3,5-NTS
38B-9 seems to have been “skipped”
by both tracers
Less return of n-propanol than of
1,3,5-NTS
Normalized tracer returns
0.01
0.009
38C-9 propanol in
38C-9 propanol in
38D-9 propanol in
38D-9 propanol in
38C-9 1,3,5-NTS
38D-9 1,3,5-NTS
0.008
0.007
E(1/day)
0.006
steam
brine
steam
brine
0.005
0.004
0.003
0.002
0.001
0
0
50
100
days
150
Conclusion
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Lab work - n-propanol is appropriate
as a geothermal tracer in smaller
volume by using SPME-GC-FID
Lab work - Alcohols can be a powerful
tool in determining two-phase
pathways in reservoirs
Acknowledgements
This work was supported by grants from
the Department of Energy. Done with
the support of Coso Operating
Company, LLC; and the Geothermal
Program Office of the Naval Air
Weapons Station.
Acknowledgements
Peter Rose1, Nick Dahdah1, Michael
Adams1, Jess McCulloch2, Cliff Buck2,
and G. Michael Shook3
1 Energy and Geoscience Institute – University of Utah
2 Coso Operating Company – Catihness Energy LLC
3 Idaho National Laboratory
References
Adams, M.C., Yamada, Y., Yagi, M., Kondo, T., and Wada, T. (2000),
“Stability of Methanol, Propanol, and SF6 as High-Temperature
Tracers,” World Geothermal Congress p. 3015-3019
Adams, M.C., Yamada, Y., Yagi, M., Kasteler, C., Kilbourn, P., and
Dahdah, N. (2004), “Alcohols as Two-Phase Tracers,” Proceedings,
Twenty-Ninth Workshop on Geothermal Reservoir Engineering
Fogler, H.S. Elements of Chemical Reaction Engineering. 3rd Edition,
New Jersey: Prentice Hall, 1999, chapter 13.
Fukuda, D., Asanuma, M., Hishi, Y., Kotanaka, K. (2005), “Alcohol
Tracer Testing at the Matsukawa Vapor-Dominated Geothermal
Field, Northeast Japan,” Proceedings, Thirtieth Workshop on
Geothermal Reservoir Engineering
References
Mella, M.J., Rose, P.E., McCulloch, J., Buck, C., Adams, M.C.,
Dahdah, N.F. (2006), “The Use of n-Propanol as a Tracer at the site
of the Coso Engineered Geothermal System,” PROCEEDINGS,
Thirty-First Workshop on Geothermal Reservoir Engineering
Stanford University,SGP-TR-179
Rose, P.E., Mella, M.J., Kasteler, C. (2003), “A New Tracer For Use in
Liquid-Dominated, High-Temperature Geothermal Reservoirs,”
GRC Transactions, 27, pp. 403-406
Supelco (2003), Chromatography Products for analysis and
Purification. Supelco p. 348-358
Questions?