rei corrosion monitoring
TRANSCRIPT
Real-time Corrosion Monitoring in Fossil-fuel-fired Boilers
For more information contact Kevin Davis at [email protected] or 801-364-6925 x23
Benefits of Corrosion Management
Reduction in unscheduled outages
Reduction in maintenance costs Tube life extension Reduction in weld
overlay coverage Improved operational
optimization – emissions vs. waterwall wastage
Quantitative assistance in fuel selection/blending decisions
Quantitative assistance in materials selection and life cycle certainty
Waterwall Corrosion
Superheater/Reheater Corrosion
Low Temperature Corrosion
Solution Approach
Evaluation of potential boiler corrosion mechanisms gas-phase sulfur species gas-phase chlorine species deposition of unreacted material
Identification of high risk locations application of CFD modeling with
integrated empirical correlations wastage measurements and/or
observations of tube failures Installation of real-time monitoring
system Data reduction including
comparisons with concurrent historical plant data
identification and validation of corrosion management strategies
“Power Plant Diagnostics Go On-Line” Mechanical Engineering, Dec 1989
Ultrasonic tube thickness
measurements
CFD-based corrosion predictions
REI Coal-Fired Boiler Corrosion Experience
Focus on impacts of firing system modifications, fuel changes, additive utilization, and operational optimization
CFD-based modeling Correlation-based approach resulting
from collaborations with EPRI and KEPRI Integrated with REI’s CFD software
(GLACIER) Real-time monitoring
Initially motivated by desire to validate modeling tools
Adaptation of an electrochemical approach in a collaborative effort with Corrosion Management (UK)
Corrosion Modeling
Prediction of fire-side corrosion through the detailed 3D modeling and advanced corrosion correlations
Waterwall and superheater corrosion mechanisms
Validated CFD Tools with Integrated Corrosion Correlations
Front Wall Rear Wall
(max = 26 mil/yr) (max = 94 mil/yr)
Side Wall Center Wall
(max = 29 mil/yr) (max = 81 mil/yr)
> 70
0
mils/yr (scale for simulations)
Real-time Corrosion Monitoring Experience
Lab-, pilot- & full-scale applications
Full-scale: Wall-fired Tangentially fired Cyclone-fired CFB
Mechanisms involving sulfur, chlorine, and bromine
Waterwall, superheater, economizer, air heater
Tube materials from inexpensive carbon steels to expensive alloys
Up to six simultaneous probes
Electrochemical Noise (EN) Corrosion Monitoring
Advantages Sensitivity Instantaneous response
allowing real-time measurement
Direct indication of corrosion
Quantitative measurement Nature of response can
indicate specific corrosion mechanism
Control and Signal Processing
Probe Hardware
Data Acquisition
Electronics
Primarily off-the-shelf components
Unique proprietary module for processing ZRA and voltage signals
Small cooling air requirements
Software
Convenient GUI-based control, monitoring, signal processing and data logging
Complete local and remote accessibility
Data Acquisition and Control
Corrosion Resistant Borders
Corroded Carbon Steel Sensor Element
Rapid Turnaround Precision Metrology
Requires late model profilometer
Modified sensor elements to provide a corrosion resistant surface for comparison
In-house software for border recognition and subtraction
Effective resolution on average corrosion depth < 0.1 micron
Quantitative Comparisons
0
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16
18
0 1 2 3 4 5 6 7 8 9 10
Profilometry Corrosion Depth (micron)
ENC
R C
orro
sion
Dep
th (m
icro
n)
F5
F7
LLL
L
L- Laboratory test in 100 MBtu/hr furnaceF5- Field test in 680 MW Coal-fired Boiler (5th floor)F7 - Field test in 680 MW Coal-fired Boiler (7th floor)
Profilometry
CFD Modeling
Lab-scale Testing
0
1
2
3
4
5
6
7
8
9
10
1/26 13:40 1/26 20:20 1/27 3:00 1/27 9:40 1/27 16:20 1/27 23:00
Date/Time
S.R. = 0.90 S.R. = 0.85S.R. = 0.90S.R. = 0.95
0
100
200
300
400
500
600
3/23/2001 4:48 3/23/2001 16:48 3/24/2001 4:48 3/24/2001 16:48 3/25/2001 4:48 3/25/2001 16:48 3/26/2001 4:48
Date & Time
Tem
pera
ture
(C)
0
0.01
0.02
0.03
0.04
0.05
0.06
Cor
rosi
on R
ate
(mm
/yr)
Metal Temperature
Corrosion Rate Temperature response
Stoichiometry response
Pilot-scale Testing
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Test 1 (0 ppm) Test 2 (~25 ppm) Test 3 (~90 ppm) Test 4 (0 ppm)
Test and H2S Level
CR
/CR
max
CorrProbeKungCorr
1.5 MW Pilot-scale Coal-fired Furnace 1.6 MW Pilot-scale Coal-fired Furnace
Probe Designs
Design approaches are tailored to simulate relevant conditions
Flush Face Water-wall crowns Duct wall surfaces Stack liner surfaces
Cylindrical Superheater/Re-heater banks Economizers Air heaters
High Temperature Boiler Applications
Waterwall
Superheater
Cyclone Boiler Waterwall Start-up Response
0
2
4
6
8
10
12
14
16
18
20
10/8/00 15:00 10/8/00 19:00 10/8/00 23:00 10/9/00 3:00 10/9/00 7:00
Cor
rosi
on R
ate
(mils
/yr)
250
300
350
400
450
500
550
Met
al te
mpe
ratu
re (d
egC
)
1 hr moving average
0
20
40
60
80
100
120
140
160
180
200
9/30/00 18:00 10/1/00 6:00 10/1/00 18:00 10/2/00 6:00 10/2/00 18:00
Cor
rosi
on R
ate
(mils
/yr
0
100
200
300
400
500
600
Met
al T
empe
ratu
re (d
egC
Steady Boiler Operation
Startup/Outage/Restart
PC Boiler Waterwall Load Response
USC Superheater Material Evaluation
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
640 660 680 700 720
Tube Metal Temperature, ºC
Cor
rosi
on R
ate,
mm
/yr
T92T91TP347HFGT122S304HHR3C
347H Metallographic Results
0
2
4
6
8
10
12
14
16
18
20
Na Mg Al Si Mn S Ca Cr Fe Zr Ni Nb Mo O
Mas
s %
Pre-Test Scale AveragePre-Test Steel AveragePost-Test Scale AveragePost-Test Steel Average
69.7 70.8 56 66.6Backscattered Electron Images of the 347H
Corrosion Element
Pre-Combustion Testing
Post-Combustion Testing
Sulfur is present in the post-test scale and steel
Nickel has been removed in the post-test scale
0
100
200
300
400
500
600
700
8/21/01 8/23/01 8/25/01 8/27/01 8/29/01 8/31/01 9/2/01 9/4/01 9/6/010
0.5
1
1.5
2
2.5
3
3.5
Corrosion Rate
Boiler Load
0
100
200
300
400
500
600
700
9/10/01 9/12/01 9/14/01 9/16/01 9/18/01 9/20/01 9/22/01 9/24/01 9/26/01 9/28/01
Date
0
10
20
30
40
50
60
70
Load
Corrosion Rate
Upper Furnace
Mid- furnace
Impact of Unreacted Fuel Deposition
Low Temperature Boiler Applications
FGD
Stack
Air Heater Exit Duct
0
50
100
150
200
250
0
0.12
0.24
0.36
0.48
0.6
16:30:00 16:45:00 17:00:00 17:15:00 17:30:00 17:45:00 18:00:00 18:15:00
Prob
e te
mp
(°F)
Cor
rosi
on ra
te, m
m/y
r
Probe A Corrosion
Probe A Temperature
0
50
100
150
200
250
0
0.12
0.24
0.36
0.48
0.6
14:20:00 14:35:00 14:50:00 15:05:00 15:20:00 15:35:00 15:50:00 16:05:00
Prob
e te
mp
(°F)
Corr
osio
n ra
te, m
m/y
r
Probe A Corrosion
Probe A Temperature
With Bromine
Without Bromine
Dewpoint Corrosion Under Oxy-firing
Dewpoint Corrosion: Impact of Bromine Additive
Oxy-firing Bituminous Coal
Dewpoint Corrosion with PRB
REI has extensive experience in the development, validation, and application of EN-based real-time corrosion monitoring including: Probe designs for waterwall, superheater, economizer, air heater
applications Environments resulting in corrosion from gas-phase and deposited sulfur,
molten sulfates, high temperature gas-phase chlorine, low temperature acid condensation
Simultaneous evaluation of multiple tube materials This experience is complemented by unique capabilities/tools
including: Advanced CFD models with integrated mechanism-specific correlations A rapid turnaround precision metrology technique Access to and experience with lab- and pilot-scale test facilities Deposit/tube characterization
Summary
Publications and Presentations
J. Beutler, K. Davis, T. Shurtz, D. Bai, R. Jafari, W. Cox “Successful Real-time Corrosion Monitoring during Co-firing of MPH Energy’s Reengineered Feedstock,” Impacts of Fuel Quality on Power Production, Snowbird, UT, October, 2014.
K. Davis, B. Adams, J. Beutler, T. Shurtz “ImpactofBromineAdditiononLowTemperatureCorrosioninAirand OxyfiredCoal Combustion,” The 39th International Technical Conference on Clean Coal & Fuel Systems, Clearwater, FL, June 2014.
K. Davis “Low and High Temperature Corrosion Associated with Pollutant Control Technologies,” Training Class for the NOx-Combustion Roundtable, Reinhold Environmental, Charlotte, NC, February 2014.
W. Cox, K. Davis, A. Fry, M. de Jong, D. Swensen “Successful real time on-line monitoring of high temperature corrosion in oxyfuel and other combustion systems,” 3rd International Oxy-Fuel Combustion Conference, Ponferrada, Spain, September 2013
A. Fry, B. Adams, T. Shurtz, K. Davis, W. Cox “Behaviour Related to Halogens for Oxycoal Retrofit of Utility Boilers,” 3rd International Oxy-Fuel Combustion Conference, Ponferrada, Spain, September 2013.
A. Fry, B. Adams, K. Davis, D. Swensen, S. Munson, W. Cox “Fire-side corrosion of heat transfer surfaces for air- and oxy-coal combustion,” 2nd Oxyfuel Combustion Conference, Yeppoon, Australia, September, 2011.
A. Fry, B. Adams, K. Davis, D. Swensen, S. Munson, W. Cox “An investigation into the likely impact of oxy-coal retrofit on fire-side corrosion behavior in utility boilers,” International Journal of Greenhouse Gas Control, 5S (2011) S179–S185.
A. Fry, B. Adams, K. Davis, D. Swensen, S. Munson, W. Cox “Fire-side corrosion of heat transfer surface materials for air- and oxy-coal combustion,” 36th International Technical Conference on Coal Utilization & Fuel Systems, Clearwater, FL, June 2011.
A. Fry, Adams, B., Davis, K., Cremer, M., Swensen, D., Munson, S., Kazalski, P., Cox, W., Oryshchyn, D., Gerdemann, S. “Topics in Oxy-Coal Retrofit of Utility Boilers Burner Principles and Fire-Side Corrosion,” The MEGA Symposium, Baltimore, MD, August 30–September 2, 2010.
K. Davis “A Real-Time Monitoring Technique for Fire-side Corrosion Characterization in Boilers” 23rd Annual ACERC Technical Conference, Provo, UT, February 2009
H. Shim, J. Valentine, K. Davis, S. Seo, T. Kim “Development of Fire-side Waterwall Corrosion Correlations using Pilot-scale Test Furnace” Fuel, 2008, 15-16, 3353-61.
H. Shim, J. Valentine, and K. Davis, S. Seo, E. Kim and T. Kim “Investigation of fire-side corrosion in a pilot-scale test furnace,” 32nd International Technical Conference on Coal Utilization & Fuel Systems, Clearwater, FL, June 2007.
Publications and Presentations (cont.)
H. Shim, J. Valentine, and K. Davis, S. Seo, E. Kim and T. Kim “Fire-side corrosion study in a coal-fired pilot-scale test furnace,” Impacts of Fuel Quality on Power Production, Snowbird, UT, October/November 2006.
K.A. Davis, T. Linjewile, J. R. Valentine, et al. “A multi-point corrosion monitoring system applied in a 1,300 MW coal-fired boiler, Anti-corrosion Methods and Materials 51 (5), 2004
K. Davis, T. Linjewile, J. Valentine, D. Swensen, D. Shino, J. Letcavits R. Sheidler, W. Cox, R. Carr and S. Harding "On-line monitoring of waterwall corrosion in a 100MW boiler with low NOx burners," The Mega Symposium: EPRI-DOE-EPA Combined Utility Air Pollutant Control Symposium, Washington, DC, August/September 2004.
K. Davis, T. Linjewile, D. Swensen, D. Shino, J. Letcavits, W. Cox, R. Carr, "A multi-point corrosion monitoring system applied in a 1300 MW coal-fired boiler." 29th International Technical Conference on Coal Utilization & Fuel Systems, Clearwater, FL, April 2004.
T. Linjewile, J. R. Valentine, K.A. Davis, N.S. Harding, W. Cox (2003) “Prediction and real-time monitoring techniques for corrosion characterization in furnaces,” Materials at High Temperature 20, 175.
K. Davis "Corrosion in solid fuel fired boilers: insight and solutions using computational fluid dynamics and electrochemical monitoring," 17th Annual ACERC Technical Conference, Salt Lake City, UT, February 2003.
K. Davis, T. Linjewile, J. Valentine and W. Cox "Prediction and real-time monitoring techniques for corrosion characterization in furnaces," 19th International Pittsburgh Coal Conference, September 2002.
K. Davis, T. Linjewile, G. Green, W. Cox R. Carr, N. Harding "Evaluation of an on-line technique for corrosion characterization in boilers," 3rd International Workshop on Life Cycle Issues in Advanced Energy Systems, Woburn, UK, June 2002.
T. Linjewile, K. Davis, G. Green, W. Cox, R. Carr, N. Harding, D. Overacker "On-line technique for corrosion characterization in utility boilers," United Engineering Foundation Conference on Power Production in the 21st Century: Impacts of Fuel Quality and Operations, Snowbird, UT, October 2001.
K. Davis, G. Green, T. Linjewile, S. Harding "Evaluation of an on-line technique for corrosion characterization in furnaces," 2001 Joint International Combustion Symposium, AFRC/JFRC/IEA, Kauai, HI, September 2001.
K. Davis, C. Lee, R. Seeley, S. Harding, M. Heap, and W. Cox "Waterwall corrosion evaluation in coal-fired boilers using electrochemical measurements," 25th International Technical Conference on Coal Utilization & Fuel Systems, Clearwater, FL, March 2000.