ABMA
American
Boiler Manufacturers
Association
1500 Wilson Boulevard
Arlington VA 22209
DoE
United States
Department
of Energy
Division of Power Systems
Energy Technology Branch
Washington DC 20545
EPA
U S Environmental Protection Agency
Office of Research and Development
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
EPA 600 7 79 041a
February 1979
Field Tests of Industrial
Stoker Coal-fired Boilers
for Emissions Control
and Efficiency
Improvement-Site B
Interagency
Energy/Environment
R&D Program Report
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development. U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of. and development of, control technologies for energy
systems; and integrated assessments of a wide range of energy-related environ-
mental issues.
EPA REVIEW NOTICE
This report has been reviewed by the participating Federal Agencies, and approved
for publication. Approval does not signify that the contents necessarily reflect
the views and policies of the Government, nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service. Springfield, Virginia 22161.
-------
EPA-600/7-79-041a
February 1979
Field Tests of industrial Stoker
Coal-fired Boilers for Emissions
Control and Efficiency Improvement
Site B
by
J.E. Gabrielson, P.L. Langsjoen, and T.C. Kosvic
KVB, Inc.
6176 Olson Memorial Highway
Minneapolis, Minnesota 55422
lAG/Contract Nos. IAG-D7-E681 (EPA), EF-77-C-01-2609 (DoE)
Program Element No. EHE624
Project Officers: Robert E. Hall (EPA) and William T. Harvey. Jr. (DoE)
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
U.S. DEPARTMENT OF ENERGY
Division of Power Systems/Energy Technology Branch
Washington, DC 20545
and
AMERICAN BOILER MANUFACTURERS ASSOCIATION
1500 Wilson Boulevard
Arlington, VA 22209
-------
ACKNOWLEDGMENTS
The authors wish to express their appreciation for the assistance
and direction given the program by project monitors W. T. (Bill) Harvey of
the United States Department of Energy (DOE) and R. E. (Bob) Hall of the
United states Environmental Protection Agency (EPA). Thanks are due to
their agencies, DOE and EPA, for co-funding the program.
He would also like to thank the American Boiler Manufacturers
Association (ABMA) staff members W. B. (Bill) Marx, Executive Director,
W. H. (Bill) Axtman, Assistant Executive Director, and B. C. (Ben) Severs,
Project Manager, and the members of their Stoker Technical Committee chaired
by W. B. (Willard) McBurney of the McBurney Corporation for providing support
through their *-im«» and travel to manage and review the program. The partici-
pating committee members listed alphabetically are as follows:
F. C. Belsak Island Creek Coal
R. D. Bessette island Creek Coal
T. Davis Combustion Engineering
J. Dragos Consolidation Coal
T. G. Healey Peabody Coal
W. B. Hoffmann Hoffmann Combustion Engineering
N. H, Johnson Detroit Stoker
K, Luuri Riley Stoker
J. Mullan National Coal Association
E. A. Nelson Zurn Industries
E. Poitrass the McBurney Corporation
P. E. Ralston Babcock and Wilcox
D. C. Reschley Detroit Stoker
R. A. Santos Zurn Industries
W. Sisken U.S. Department of Energy
We would also like to recognize the KVB engineers and technicians
who spend most of their time in the field, often under adverse conditions,
testing the boilers and gathering data for this program. Those involved to
date are George Moilanen, Jim Burlingame, Russ Parker, Jon Cook, John Rech,
and Jim Demont.
Finally, our gratitude goes to the host boiler facilities who
invited us to test their boilers. At their request, these facilities will
remain anonymous to protect their own interests. Without their cooperation
and assistance this program would not have been possible.
KVB 15900-524
ii
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TABLE OF CONTENTS
Section Page
ACKNOWLEDGMENTS 11
LIST OP FIGURES V
1.0
2.0
3.0
4.0
5.0
LIST OF TABLES
INTRODUCTION
EXECUTIVE SUMMARY
DESCRIPTION OF FACILITY TESTED AND COALS FIRED
3.1 Boiler B Description
3.2 Overfire Air System
3,3 Flyash Reinjection System
3.4 Predicted Performance Data
3.5 Test Port Locations
3.6 Coals Utilized
TEST EQUIPMENT AND PROCEDURES
4.1 Gaseous Emissions Measurements
4.1.1 Analytical Instruments and Related Equipment
4.1.2 Recording Instruments
4.1.3 Gas Sampling and Conditioning System
4,2 Gaseous Emission Sampling Techniques
4.3 Sulfur Oxides (SOx) Measurement and Procedure
4.4 Particulates Measurement and Procedure
4.5 Particle Size Distribution Measurement and Procedure
4,6 Coal Sampling and Analysis Procedure
4.7 Ash Collection and Analysis for combustibles
_4.8 . Boiler Efficiency Evaluation
4.9 Modified Smoke Spot Number
4.10 Trace Species Measurement
4. 11 Flyash Resistivity Measurement
TEST RESULTS AND OBSERVATIONS
5.1 Overfire Air
5.2 Flyash Reinjection
5.2.1 Test 7, Reinjection Rate Measurement
5.2.2 Test 23, Reduced Reinjection
5,3 Excess Oxygen and Grate Heat Release
5.3.1 Excess Oxygen Operating Levels
5.3.2 Particulate Loading vs Excess Oxygen and
Boiler Load
5.3.3 Carbon Monoxide vs Excess Oxygen and
Boiler Load
Vll
1
3
9
9
11
12
13
14
14
19
19
19
24
24
24
26
28
30
34
35
36
36
37
39
41
41
48
48
49
53
53
53
57
KvB 15900-524
iii
-------
Section
Page
5.4
5.5
5.6
5.7
5.8
5.3.4 Combustibles vs Excess Oxygen and
Boiler Load
5.3.5 Nitric Oxide vs Excess Oxygen and
Boiler Load
5.3.6 Boiler Efficiency vs Excess Oxygen and
Boiler Load
Coal Properties
Particle Size Distribution
Efficiency of Pollution Control Equipment
Modified Smoke Spot Number
Source Assessment Sampling System
APPENDIX A - Overfire Air Flow Traverse Data
APPENDIX B - Overfire Air Flow Calculation
APPENDIX C - Sulfur Balance Summary
APPENDIX D - English and Metric Units to SI Units
APPENDIX E - SI Units to English and Metric Units
APPENDIX F - SI Prefixes
APPENDIX G - Emission Units Conversion Factors for
Typical Coal Fuel
57
62
62
68
73
79
81
87
99
100
101
102
103
104
105
A Data Supplement Containing all the Data Obtained at Site B is
available under the same title (followed by "Data Supplement")
and having the same EPA number followed by the letter b rather
than a.
KVB 15900-524
iv
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LISTOF FIGURES
Figure Page
3-1. Boiler B sectional side elevation 10
3-2. Boiler B schematic 15
3-3. Boiler B sample plane geometry 16
4-1. Flow schematic of mobile flue gas monitoring laboratory 25
4-2. SOx sample probe construction 27
4-3. Sulfur oxides sampling train 27
4-4. Particulate sampling train 29
4-5. Brink cascade impactor sampling train schematic 31
4-6. Field service type smoke tester 37
4-7. Source Assessment Sampling System (SASS) flow diagram 38
5-1. Overfire air flow vs. OFA draft reading 43
5-2. Particulate loading broken down into combustible and
inorganic fractions for three overfire air test sets 45
5-3. Nitric oxide emissions vs. excess oxygen at 500 to
600 x 1Q3 BTO/ft2-hr grate heat release showing the
reduction in nitric oxide concentration with reduced
rear overfire air 46
5-4. Nitric oxide emissions vs. excess oxygen at 300 to
400 x 10-* BTU/ft2-hr grate heat release showing no
significant reduction in nitric oxide concentration
when the rear overfire air flow is reduced 47
5-5. Fly ash flow rates for different reinjection configurations 50
5-6. Particle size concentrations for boiler outlet particulates
under normal and reduced fly ash reinjection conditions 52
5-7. Excess oxygen operating levels vs. grate heat release
for all tests run at Test Site B 54
5-8. Relationship between grate air velocity and particulate
loading 55
5-9. Particulate loading at the boiler outlet vs. grate heat
release and coal type 58
5-10. Carbon monoxide emissions vs. excess oxygen and grate
heat release 59
5-11. Combustible content of the boiler outlet fly ash vs.
grate heat release 60
KVB 15900-524
-------
Figure Page
5-12. Combustible content of the bottom ash vs. grate heat
release 61
5-13. Nitric oxide concentration vs. excess oxygen and grate &3
heat release
5-14. Nitric oxide trend lines as a function of excess oxygen
and boiler load 64
5-15. Nitric oxide emissions vs. grate heat release for all
test conditions 65
5-16. Boiler efficiency vs. grate heat release for all tests 66
5-17. Dry gas heat loss vs. excess oxygen for all test conditions 67
5-18. Size consistency of "as-fired" Kentucky Cumberland coal
vs. ABMA recommended limits of coal sizing for spreader
stokers 69
5-19. Size consistency of "as-fired" Hatfield coal vs. ABMA
recommended limits of coal sizing for spreader stokers 70
5-20. Size consistency of "as-fired" Southeast coal vs. ABMA
recommended limits of coal sizing for spreader stokers 71
5-21. Size consistency of "as-fired" coal from dead storage
vs. ABMA recommended limits of coal sizing for spreader
stokers 72
5-22. Banco classifier and sieve analysis particle size
distribution 75
5-23. Brink cascade impactor particle size distribution 76
5-24. SASS gravimetric particle size distribution 77
5-25. Multiclone dust collector efficiency vs. grate heat
release and coal selection 82
5-26. Multiclone outlet particulate loading vs. grate heat
release and coal selection 83
5-27. Modified smoke spot number vs. particulate loading at
the boiler outlet 85
5-28. Modified smoke spot number vs. combustible loading at
the boiler outlet 86
KVB 15900-524
-------
LIST OF TABLES
Table Page
2-1 Emission Data Summary 7
3-1 Boiler B Predicted Performance Data 13
3-2 As-Fired Proximate Analysis of Coals Tested in Boiler B 17
5-1 Effect of Overfire Air on Emissions and Efficiency 42
5-2 Effect of Flyash Reinjection on Emissions and Efficiency 51
5-3 Effect of Excess Oxygen on Emissions and Efficiency 56
5-4 Particle Size Distribution Tests and Methodology Used 74
5-5 Particle Size Distribution Test Results 78
5-6 Efficiency of Pollution Control Equipment 80
5-7 Modified Smoke Spot Data 84
5-8 SASS Tests Run at Site B 87
5-9 Polynuclear Aromatic Hydrocarbons Analyzed in Site B
SASS Samples 88
5-10 Particulate Emissions Summary 89
5-11 Summary of Heat Losses and Efficiencies 90
5-12 summary of Percent Combustibles in Refuse 91
5-13 Coal Sizing Summary 92
5-14 Fuel Analysis Summary, Kentucky Cumberland Coal 93
5-15 Fuel Analysis Summary, Hatfield Coal 94
5-16 Fuel Analysis Summary, Southeast Coal 95
5-17 Fuel Analysis Summary, Coal from Dead Storage 96
5-18 Summary of Mineral Analysis of Coal Ash 97
5-19 Summary of Steam Flows and Heat Release Rates 98
KVB 15900-524
vii
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SECTION 1.0
INTRODUCTION
In recent years the vast majority of industrial boiler instal-
lations have been packaged or shop assembled gas and oil fired boiler units
which could be purchased and installed at substantially lower costs than
conventional coal burning boiler-stoker equipment. Because of the decline
in this market area, little or no work has been done in recent years to
improve specification data and information made available to Consulting
Engineers and Purchasers of coal burning boiler-stoker equipment. The
current implementation of more rigid air pollution regulations has made it
difficult for many coal burning installations to comply with required stack
emission limits, and this has become a further negative influence on coal
burning installations.
A field test program to address this problem has been awarded to the
American Boiler Manufacturers Association (ABMA) . The program is sponsored
by the Department of Energy (DOE) under contract number EF-77-C-01-2609, and
co-sponsored by the United States Environmental Protection Agency (EPA),
under inter-agency agreement number IAG-D7-E681. The program is directed by
an ABMA Stoker Technical Committee which, in turn, has subcontracted the field
test portion to KVB, Inc., of Minneapolis, Minnesota.
The objective of the test program is to produce information which
will increase manufacturers* ability to design and fabricate stoker boilers
which are an economical and environmentally satisfactory alternative to impor-
tation and combustion of expensive oil. In order to do this, it is necessary
to define stoker boiler designs which will provide efficient operation with
minimum gaseous and particulate emissions, and define what those emissions are
in order to facilitate preparation of attainable national emission standards
for industrial size, coal-fired units.
Further objectives are to: provide assistance to stoker boiler
operators in planning for coal supply contracts; refine application of
existing pollution control equipment with special emphasis on performance; and
contribute to the design of new pollution control equipment.
1 KVB 15900-524
-------
In order to meet these objectives, it is necessary to determine
emissions and efficiency as functions of changes in coal analysis and sizing,
degree of flyash reinjection, overfire air admission, ash handling, grate
size, etc., for various boiler, furnace and stoker designs.
This report is the Final Technical report for the second of eleven
boilers to be tested under the program described above. It contains a
description of the facility tested, the coals fired, the test equipment and
procedures, and the results and observations of testing. A data supplement
to this report contains the "raw" data sheets from the 33 tests conducted.
The data supplement has the same EPA report number as this report except that
it is followed by "b" rather than "a." As a compilation of all data obtained
at this test site, it acts as a research tool for further data reduction
and analysis as new areas of interest are uncovered in subsequent testing.
At the completion of this program, a Final Technical Report will
combine and correlate the test results from all sites tested. This final
report will provide the technical basis for the ABMA publication on "Design
and Operating Guidelines for Industrial Stoker Firing," and will be avail-
able to interested parties through the ABMA, EPA, or DOE. A separate report
covering trace species data will also be written at the completion of this
program. It, too, will be available to interested parties through the ABMA,
EPA or DOE.
Data in this report is presented in English units. It is EPA
policy to use S.I. units in all reports. However, it was determined that
English units were necessary in this case. Conversion tables are provided
in the appendix for those who prefer S.I. units.
To protect the interests of the host boiler facilities, each test
site in this program has been given a letter designation. As the second
site tested, this is the Final Technical Report for Test Site B under the
program entitled, "A Testing Program to Update Equipment Specifications and
Design Criteria for Stoker Fired Boilers."
KVB 15900-524
-------
SECTION 2.0
EXECUTIVE SUMMARY
This section outlines the major relationships and conclusions drawn
from the test program at Site B. Comments are organized into groups accord-
ing to the parameter studied. The test data is summarized in Table 2-1 at the
end of this section, and in Tables 5-10 through 5-19 at the end of Chapter 5,
Test Results and Observations.
Overfire Air. Increasing the rear overfire air resulted in reduced
particulate emissions and increased boiler efficiency. Three overfire air
test sets were run with the following results:
• Particulate emissions were reduced 25% at the boiler
outlet when the rear overfire air flow was increased
by 28%.
• Combustible and inorganic fractions of the particulate
emissions were equally reduced by the overfire air in
these tests.
• Nitric oxide emissions were not significantly affected
by the change in overfire air flow.
* Carbon monoxide emissions were negligible under all
conditions tested and, therefore, showed no change.
• Boiler efficiency increased 0.38% in one test set and
2.93% in another test set when overfire air flow at the
back of the furnace was increased. The increase in
efficiency was attributable for the most part to a
reduction in carbon carryover.
• The overfire air system accounts for 20% to 30% of the
total air introduced to the furnace at intermediate and
high loads.
Flyash Reinjection from the multiclone dust collector was reduced
30% for one high load test. The results were as follows:
• Particulate emissions at the boiler outlet were reduced
39%.
KVB 15900-524
-------
• Particle size distribution data indicate that the largest
changes in mass concentration occurred above ten micrometers
in size.
• Boiler efficiency was reduced 2.2% by the reduction in re-
injection rate. One and one- third percent of this efficiency
loss represents the heating value of the 30% flyash not
reinjected.
Excess Oxygen and Grate Heat Release. The boiler at Test Site B was
tested under a full range of loads and excess air conditions. Some of the
relationships observed were as follows :
• Particulate loading was observed to increase with grate
air velocity.
• Excess oxygen had only a minor effect on particulate load-
ing and was not an effective control technique for parti-
culate reduction on this boiler.
• Particulate loading at the boiler outlet increased with
increasing grate heat release at a rate of about 1.6
lb/106BTU for each 1 x 10$ BTU/ft2-hr. This translates
to an 8% increase in particulate loading for each 10%
increase in boiler load.
• Nitric oxide concentration increased an average of 30 ppm
for each one percent increase in 02 at constant boiler
load.
• Nitric oxide concentration increased an average of 20 ppm
for each 10% increase in boiler load at constant excess
Average nitric oxide concentration at the boiler outlet
was 270 ppm t 45 ppm and remained constant at all loads
because of the countering effects on NO formation of
excess air and boiler load.
Carbon monoxide emissions were negligible under all con-
ditions tested and, therefore, showed no change.
Combustible content of the flyash was found to be inde-
pendent of excess oxygen and only slightly dependent on
boiler load. Combustibles were highest in the 70% to 80%
load range and dropped off slightly at both ends.
Boiler efficiency was independent of load, but increased
with decreasing excess air at a rate of about 0.6% for
each 1% ©2 reduction.
KVB 15900-524
-------
Coal Properties. The four test coals fired in Boiler B were nearly
identical in chemical analysis and size consistency. The size consistency
of all coals was within the ABMA recommended limits for spreader stokers.
The impact of coal selection on emissions and efficiency was as follows:
* Particulate emissions - no relationship observed.
• Nitric oxide emissions - no relationship observed.
• Carbon monoxide emissions - no relationship observed.
• Boiler efficiency - no relationship observed.
Particle Size Distribution of the flyash was measured at the boiler
outlet, multiclone outlet, and after the electrostatic precipitator. Bahco
classifier, Brink cascade impactor, SASS gravimetric, and sieve methodology
were used to measure this parameter. The results are as follows:
• Boiler outlet particulates were measured at 6% below 10
micrometers using the Bahco classifier, and 12% to 39% below
10 micrometers using SASS gravimetrics. The Bahco results
were expected to be low because of the method used to
obtain the sample. Sieve analysis showed the largest
particulate size to be above 1650 micrometers.
• Multiclone outlet particulates were measured at 78% below
10 micrometers using SASS gravimetrics. Extrapolation of the
Brink cascade impactor data yielded similar results.
f
• ESP outlet particulates were measured at 89% and 94%
below 10 micrometers using SASS gravimetrics.
• Coal selection, boiler load, and excess oxygen did not
show any consistent relationship to particle size distri-
bution of the flyash.
Efficiency of Pollution Control Equipment. Twenty simultaneous par-
ticulate loading tests were run across the multiclone dust collector. Two
simultaneous particulate tests were run across the multiclone and the elec-
trostatic precipitator combined. The results were as follows:
• Multiclone dust collection efficiency ranged from 92.7%
to 96.6% and averaged 94.6%.
• Combined multiclone and ESP efficiency was measured at
99.82% and 99.88%. Thus, ESP efficiency was about 96%
KVB 15900-524
-------
• Combustion variables such as excess air, overfire air,
boiler load, and coal selection did not have a discernable
effect on collection efficiency.
Modified Smoke Spot Number. Smoke spot readings were taken with a
Bacharach smoke spot tester at the boiler outlet using modified procedures.
No relationship was found between smoke spot number and either particulate
loading or combustible loading.
Source Assessment Sampling System (SASS). Seven SASS tests were
run at Test Site B. Five were run at the boiler outlet and two at the ESP
outlet. The sample catches are being analyzed for total polynuclear content
and seven specific polynuclear aromatic hydrocarbons. Test results will be
reported on under separate cover at the conclusion of this test program.
Boiler Emission Profile. Each of the boiler's measured emissions
are plotted against grate heat release in this report. In addition. Table
5-19 presents the computed front foot heat release rates and the furnace
heat release rates for each test. All of this information will be valuable
when comparing the emission profiles of various boiler/stoker combinations
and designs. It will also provide accurate data on which to base reasonable
emission standards in the future.
The following data table summarizes the reduced data from the
tests performed at Test Site B.
KVB 15900-524
-------
TABLE 2-1.
EMISSION DATA SUMMARY, TEST SITE B
TMt
No.
1
2
3
4
5
6
7
8
9
10A
10B
IOC
10D
11
12
13ft
13B
13C
14A
14B
14C
14D
15
16
17
18
19
20
21
22
23
24
25
26
26C
27
28"
29
30
31
32
33
Date
12/21/77
12/21/77
1/05/78
1/06/78
1/08/78
1/11/78
1/12/78
1/26/78
1/26/78
1/27/78
1/28/78
1/28/78
2/03/78
2/04/78
2/06/78
2/07/78
2/09/78
2/17/78
2/18/78
2/18/78
2/20/78
2/20/78
2/22/78
3/02/78
3/03/78
3/05/78
3/09/78
3/09/78
3/16/78
3/17/78
3/18/78
3/20/78
3/21/78
NOTES!
Oj CO2 CO NO Part. Part. Excess
Load % % ppm pptn Blr Out Mech DC Out Air
% Coal Type of Test Conditions dry dry dry dry Ib/lO^BTD Ib/lO^TD %
41 X SOx as found 9.9 9.4 OOS 301
28 K Part blr out - low load 11.3 8.0 OOS 333 6.6,
27 B Part blr £ nech out - low load 10.9 8.2 245 292 8.9
47 X Part blr s mech out - as found 8.0 11.4 56 243 9.7
47 B Brink blr out - as found 6.6 12.1 45 203
75 S Part blr £ mech out - norm OFA 5.2 13.7 32 214 11.7
76 S Part blr £ mech out - reduced OFA 4.4 14.3 139 197 10.3
75 K Part blr £ mech out - high 02 10.2 8.9 25 306 15.5
73 X Part blr fi nech out - norm O2 6.9 12.1 120 237 8.2
31 S Vary excess air as found 11.3 8.4 295 351
- reduce 10.0 9.0 229 311
- reduce 8.8 10.1 148 273
- increase 14.0 5.8 601 437
48 R Part blr £ mech out - norm OFA 8.8 10.8 96 339 7.2
49 R Part blr S nech out reduced OFA 8.0 11.8 36 280 9.6
72 R Vary excess air - as found 7.5 11.6 53 267
- reduce 5.9 13.0 36 226
reduce 4.7 13.9 28 194
96 R Vary excess air - as found 5.8 13.3 24 261
- reduce 4.6 14.5 22 258
- reduce 3.4 15.4 125 225
- increase 6.4 12.8 34 296
87 R Sass, Part, SOx blr £ ESP out - low O2 4.3 14.7 27 215 12.5
89 R Sasa Part. SOx blr S ESP out - norm Oj 7.0 12.1 48 294 14.6
88 R Part blr £ nech out - norm O2 6.6 12.4 47 320 10.7
74 S Part blr fi mech out - palling bottom ash 6.5 12.9 163 287 12.8
75 X Part blr £ mech out - low O2 4.7 14.4 35 239 10.5
73 X Part blr £ mech out - norm O2 6.8 12.4 35 332 10.6
73 H Part blr fi mech out - norm OFA 6.8 12.4 34 310 9.2
72 H Part blr fi mech out - reduced OFA 6.3 12.9 103 219 12.3
99 K Part blr S. mech out reduced reinj S.S 13.6 41 254 9.6
99 S Part & sizing blr S mech out - max load S.I 13.9 72 256 13.9
100 K Part s sizing blr fi mech out - max load 5.3 13.7 60 317 15.8
99 H Part blr £ mech out - max load 5.3 13.7 83 287 12.7
Sizing blr £ mech out - max load 4.4 14.7 62 252
79 K Part blr s mech out - reduced OFA 6.4 12.6 44 311 11.7
81 K Part blr £ mech out - norm OFA 6.5 12.7 47 305 10.0
79 K Gaseous only - as found 6.6 12.5 40 259
78 H SASS blr out, SOx blr £ ESP out - as found 6.0 13.0 46 232
77 K SASS blr out, SOx blr £ ESP out - as found 6.0 13.0 27 259
78 H SOx blr out - as found 5.9 13.1 31 235
79 S SASS blr out, SOx blr out - as found 6.1 12.9 47 241
Gaseous data (Oj, C02, CO, NO) obtained at boiler outlet
Particulate and SOx data obtained at location specified under "Type of Test"
0.54
0.45
0.47
0.76
0.83
0.52
0.48
0.50
0.023*
0.018*
0.47
0.81
0.56
0.56
0.62
0.82
0.49
3.53
0.60
0.64
0.59
0.34
84
109
100
59
43
31
25
89
46
110
85
68
182
69
59
53
37
27
36 '
27
18
42
25
47
44
43
28
46
46
41
34
31
32
32
25
42
43
44
38
38
37
39
Coal Supplier: K-Kentucky Cumberland, H-Hat field, S- Southeast, R-Reload from long term storage
•
Tests 15 and 16 Participates measured at the boiler outlet and the ESP outlet
N02 data was not acquired due to inserviceability of NOx converter portion of HO-NO2
Conversion tables are given in the appendix for converting from English units to SI
analyzer
units
KVB 15900-524
-------
SECTION 3.0
DESCRIPTION OF FACILITY TESTED AND COALS FIRED
This Section discusses the general physical layout and operational
characteristics of Boiler B. The coals utilized in this test series are
also discussed.
3.1 BOILER B DESCRIPTION
Boiler B is a single pass Riley boiler with Riley spreader stoker.
It has a continuous rating of 200,000 Ib/hr steam. Current operation of
the boiler is at 185 psi and 500°F steam with 225°F feedwater. However, the
boiler was designed for 750 psi to allow for future upgrading to 650 psi at
750°F steam with 350°F feedwater. A sectional side elevation of the unit is
shown in Figure 3-1. An abbreviated list of boiler design data follows:
Riley Boiler (VOSP) built 1974
Rated Steaming Capacity (continuous) 200,000 Ib/hr
Peak Steaming Capacity (2 hrs in 24) 220,000 Ib/hr
Economizer Heating Surface 4,110 ft2
Superheater Heating Surface 1,900 ft2
Water Wall Heating Surface 2,820 ft2
Boiler Heating Surface 15,038 ft2
Furnace Width (centerline to centerline water-
wall tubes) 20'7-3/4"
Furnace Depth (front to back) 17'4-11/16"
Furnace Height (mean) 36'0"
Furnace Volume 12,910 ft3
Design Pressure 750 psig
Operating Pressure 185 psig
Feedwater Temperature 255°F
Final Steam Temperature (superheater) 500°F
Furnace Heat Release 2. OxlO^TD/ft3/hr
Furnace Residence Time 2.7 sec
Velocity Flue Gas in Furnace 11.6 ft/sec
Velocity Flue Gas Entering Boiler 51 ft/sec
Velocity Flue Gas Entering Economizer 52 ft/sec
Controls Foxboro
KVB 15900-524
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<»
®
©
•• -'! r-^ s— . ,
j^iw^-i^ ^7 -^-
9flfi-nr: VH
-•—teu
> r J
Figure 3-1. Boiler B sectional side elevation
KVB 15900-524
10
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Riley Stoker
Feeders 5 - Riley model F
Grate Type Split traveling grate with front discharge
Grate Width 20*0-3/8*
Grate Length (between shaft centers) 20'0"
Effective Grate Area 370 ft2
Grate Heat Release 7.4xl05BTU/ft2/hr
3.2 OVERFIRE AIR SYSTEM
The overfire air system on Boiler B consists of two rows of
17 jets each on the back wall and one row of 17 jets on the front wall
above the feeders. In addition, the OFA fan supplies air to the air swept
cut-off plate and deflector tuyeres for cooling, and to two 3/4 inch
underfeeder air jets under each of the five Riley feeders.
The overfire air fan extracts air from the undergrate air duct
downstream of the forced draft fan. It was set up by a Riley service man
so that most of the air enters the rear of the furnace and very little
enters through the front wall. This was intended to create a circulation in
the furnace which would sweep up the front wall and down the rear wall.
Dampers on the two rear overfire air headers are ganged together and can be
operated remotely from the panel board.
The overfire air design data is as followsi
Front Row: 17-1-1/4" nozzles
spaced @ 13-1/4" (8-9/32" adjacent to center nozzle)
7«8-5/8" above grate
18° 30' below horizontal
Rear Rows (2)s 17-1-1/4" nozzles each row
spaced @ 13-1/4"
2-1/2° below horizontal
Upper row 5*9" above grate
Lower row 2"0" above grate
As Found Operating Pressures Front 7"
Rear Upper 22"
Rear Lower 25" H2O
KVB 15900-524
11
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3.3 FLY ASH REINJECTION SYSTEM
Boiler B reinjects flyash continuously from the boiler hopper and
from a portion of the centrifugal dust collector. The dust collector is a
VOP Design 104 Dynamic Centrifugal Collector having 140 ten-inch collection
tubes. It is equipped with front storage hoppers and rear reinjection
trough hoppers. According to the proposal specifications, 60 to 80% of the
collected flyash is reinjacted. Internal dampers are designed to direct the
larger particles to the reinjection trough. In theory this is a good idea
because the larger particles contain a larger carbon component and are less
likely to be re-entrained in the flue gas. The collector has a guaranteed
efficiency of 90% based on an inlet dust analyzing ten percent less than
ten micrometers.
No provisions were made for diverting the ash from the reinjection
system to a storage hopper or alternate disposal system. Thus, in order to
stop the reinjection for test purposes, it was necessary to remove the
venturi section at the bottom of the hopper spouts and add a section of
pipe to extend the downspouts into sealed, air tight, 55 gallon drums.
There were no rotary dust valves on the downspouts to compensate for the
negative pressure in the hoppers.
Design data on the flyash reinjection system is as follows:
Boiler Hopper: 6 - 2-1/2" discharge nozzles
spaced @ 2*9-1/8" (center two @ 3'3-3/4")
18" above grate
7° below horizontal
Dust Collector Hopper: 7 - 2-1/2" discharge nozzles
spaced @ 6'10-13/16"
18" above grate
7° below horizontal
As Found Operating Pressures: Boiler hopper reinjection hdr - 5" H2O
Mechanical hopper reinjection hdr - 5" H2O
KVB 15900-524
12
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3.4
PREDICTED PERFORMANCE DATA
Boiler B predicted performance data is given in Table 3-1
below. The performance predictions are based on a coal which is not less
favorable than 1-1/4" nut to slack for friable coal, 3/4" nut to slack
for non-friable coal, and with not more than 50% passing through a 1/4-inch
round mesh screen. The coal shall be delivered across the feeder hopper
without segregation.
TABLE 3-1. BOILER B PREDICTED PERFORMANCE DATA
Steam Flow - PPH
Slowdown - PPH
Boiler Exit Gas - °F
Economizer Outlet Gas - °F
Coal - PPH
Air - PPH
Gas - PPH
Heat Release - BTU/sq.ft.
Grate Heat Release - BTU/sq.ft.
Heat Release - BTU/cu.ft.
* Dust Loading - #/MKB
* Dust Loading - Grains/ACFM
Efficiency
Excess Air in Flue Gas (%)
Ambient Air Temperature - °F
Steam Quality - PPM
Steam Temperature Leaving Boiler - °F
Superheater Outlet Pressure - PSIG
Draft Loss - FD Duct - "W.C.
Draft Loss - Stoker Grate - "W.C.
Draft Loss - Boiler - "W.C.
Draft Loss - Dust Collector - "W.C.
Draft Loss - Economizer - "W.C.
Draft Loss - Electrostatic Precipitator
ID Duct Work
Total FD Draft Loss
Total ID Draft Loss - "W.C.
Without Reinjection
from D.C.
200,000
10,000
584
350
20,731
270,353
289,011
82,682
695,000
19,912
1.86
.59
81.88
31
80
1
500
185
0.87
2.18
1.33
3.15
2.72
and
'1.75
3.06
8.94
* Based on 20% Ash Fuel; Coal - C - 72.3% N2
H2 T- 4.9% 02
S - 0.6% H2O
Ash - 10.0% HHV
Reinjection
from D.C.
200,000
10,000
578
350
20,170
263,037
281,190
80,444
676,000
19,373
5.57
1.77
84.16
- 1.2%
- 5.0%
- 6.0%
as fired 12,400 BTO/lb
KVB 15900-524
13
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3.5 TEST PORT LOCATIONS
Sample ports were installed at the locations shown on the boiler
schematic, Figure 3-2. Whenever participate loading was measured it was
measured simultaneously at the boiler outlet and at the mechanical collector
outlet using a 24-point traverse. The geometry of these two sample locations
is shown in Figure 3-3. On two occasions particulate loading was measured at
the electrostatic precipitator outlet. This duct, not illustrated here, had
a cross-sectional area of 28.53 ft2. It led directly to the stack, and the
dust loadings measured at the precipitator outlet should be very close to
what would be measured at the stack in a compliance test.
A gaseous probe was placed in the center of the duct through each
of the six test ports at the boiler outlet. Gaseous measurements of 02,
C02' co and NO were obtained by pulling both individual and composite
samples through these probes. When particulates were being sampled, gaseous
samples were pulled simultaneously from all ports except the one containing
the particulate probe at the boiler outlet. The gaseous concentrations
reported are the average of many readings taken over the course of testing.
A heated sample line was attached to one of the middle gaseous
probes at the boiler outlet. Its purpose was to eliminate losses due to
condensation when measuring NO2 and unburned hydrocarbons. However, problems
due to hydrocarbon contamination of the sample line and electro mechanical
problems with both the hydrocarbon analyzer and the NOx converter prevented
these measurements from being made.
3.6 COALS UTILIZED
Four coals were test fired on Boiler B during the test program.
The chemical properties of these coals are summarized in Table 3-2. All four
coals were Eastern bituminous low-sulfur coals. They differed very little
from one another. A complete fuel analysis summary for each cdal is presented
in Tables 5-14 through 5-18 in Section 5.0, Test Results and Observations.
14 KVB 15900-524
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Boiler Outlet
Sampling
Plane
Mechanical
Collu-ctor Outlet
Sampling Plane
Economizer
Split Mechanical
Collector
Mechanical Hopper
fieinjaction
Boiler Hopper
Reinjection
Figure 3-2. Boiler B schematic
KVB 15900-524
15
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BOILER OUTLET SAMPLING PLANE
| V
0 0
+ *•
+ + +
o " o o
+ + 4-
I
4'cr
I
4-
o
+
MECHANICAL COLLECTOR OUTLET SAMPLING PLANE
J + + + 4 +
3
* - + + -». +
D
"~i
^ ii 19«8"
i I—
^ + T 4
1 C
h + 3'0" +
I C
h * * + 1-
r i >
KEY: + Particulate szunple point
o Gaseous simple point
Boiler outlet cross sectional area = 76.0 ft2
Mechanical collector outlet cross sectional area = 59.0 ft2
Figure 3-3. Boiler B sample plane geometry
KVB 15900-524
16
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TABLE 3-2. AS-FIRED PROXIMATE ANALYSIS
OF COALS TESTED IN BOILER B
Coal Supplier
% Moisture
% Ash
% Volatile
% Fixed Carbon
BTD/lb
% Sulfur
Initial Deformation
of Ash (Reducing) ,°F
Kentucky
Cumberland
4.27
7.72
34.24
53.77
13220
0.90
2490
Hatfield
3.93
8.79
33.65
53.63
13137
0.93
2550
Southeast
2.90
9.02
34.19
53.89
13201
0.78
2607
Reload
4.38
6.40
34.71
54.51
13432
0.77
2700+
Coal selection at Test Site B was affected by a coal strike.
During tests 1 through 10 and 18 through 33, railway car loads of coal
arrived almost daily from three suppliers. This coal was loaded directly
into live storage. For this reason, the coal fired changed almost daily and
test plans could be made no more than two or three days in advance. During
tests 11 through 17 the facility was forced to burn coal from its dead storage
some distance from the power plant. This coal, comprised of an unknown blend
of many coals, was transported to the site in trucks and unloaded into live
storage. It will often be referred to as "Reload" coal in this report.
KVB 15900-524
17
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SECTION 4.0
TEST EQUIPMENT AND PROCEDURES
This section details how specific emissions were measured and the
sampling procedures followed to assure that accurate, reliable data were
collected.
4.1 GASEOUS EMISSIONS MEASUREMENTS
(NO, NO , CO, CO , 0-, HC)
* 4* *L
A description is given below of the analytical instrumentation
and related equipment, and the gas sampling and conditioning system, all of
which are located in a mobile testing van owned and operated by KVB. The
systems have been developed as a result of testing since 1970, and are
operational and fully checked out.
4.1.1 Analytical Instruments and Related Equipment
The analytical system consists of five instruments and associated
equipment for simultaneously measuring the composition of the flue gas. The
analyzers, recorders, valves, controls, and manifolds are mounted on a panel
in the vehicle. The analyzers are shock mounted to prevent vibration damage.
The flue gas constituents which are measured are oxides of nitrogen (NO, NOx),
carbon monoxide (CO), carbon dioxide (O>2) , oxygen (&£ . and gaseous hydro-
carbons (HC).
Listed below are the measurement parameters, the analyzer model
furnished,and the range and accuracy of each parameter for the system. A
detailed discussion of each analyzer follows:
• Nitric Oxide/total oxides of nitrogen (NO/NOx)
Thermo Electron Model 10 Chemiluminescent Analyzer
Range: 0-2.5, 10, 25, 100, 250, 1000, 2500, 10,000 ppm NO
Accuracy: il% of full scale
KVB 15900-524
19
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• Carbon Monoxide
Beckman Model 315B NDIR Analyzer
Range: 0-500 and 0-2000 ppm CO
Accuracy: il% of full scale
• Carbon Dioxide
Beckman Model 864 NDIR Analyzer
Range: 0-5% and 0-20% CO2
Accuracy: ±1% of full scale
• Oxygen
Teledyne Model 326A Fuel Cell Analyzer
Range: 0-5, 10 and 25% O2 full scale
Accuracy: *1% of full scale
• Hydrocarbons
Beckman Model 402 Flame lonization Analyzer
Range: 5 ppm full scale to 10% full scale
Accuracy: ±1% of full scale
the oxides of nitrogen monitoring instrument used is a Thermo
Electron chemiluminescent nitric oxide analyzer. The operational basis of
the instrument is the chemiluminescent reaction of NO and 03 to form NO2.
Light emission results when electronically excited NO2 molecules revert to
their ground state. This resulting chemiluninescence is monitored through
an optical filter by a high sensitivity photomultiplier, the output of which
is linearly proportional to the NO concentration.
Air for the ozonator is drawn from ambient through an air dryer
and a ten micrometer filter element. Flow control for the instrument is
accomplished by means of a small bellows pump mounted on the vent of the
instrument downstream of a separator which insures that no water collects in
the pump.
KVB 15900-524
20
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The basic analyzer is sensitive only to NO molecules. To measure
NOx (i.e., NCHN02) • ***e N°2 is first converted to NO. This is accomplished
by a converter which is included with the analyzer. The conversion occurs
as the gas passes through a thermally insulated, resistance heated, stainless
steel coil. With the application of heat, N02 molecules in the sample gas are
reduced to NO molecules, and the analyzer now reads NOx. NO2 is obtained by
the difference in readings obtained with and without the converter in operation.
Specifications: Accuracy 1% of full scale
Span Stability ±1% of full scale in 24 hours
Zero Stability ±1 ppm in 24 hours
Power Requirements 115±10V, 60 Hz, 1000 watts
Response 90% of full scale in 1 sec. (NOx mode) ,
0.7 sec NO mode
Output 4-20 ma
*
Sensitivity 0.5 ppm
Linearity il% of full scale
Vacuum detector operation
Range: 2.5, 10, 25, 100, 250, 1000, 2500, 10,000
ppm full scale
Carbon Monoxide concentration is measured by a Beckman 315B non-
dispersive infrared analyzer. This instrument measures the differential
in infrared energy absorbed from energy beams passed through a reference
cell (containing a gas selected to have minimal absorption of infrared energy
in the wavelength absorbed by the gas component of interest) and a sample cell
through which the sample gas flows continuously. The differential absorption
appears as a reading on a scale from 0 to 100 and is then related to the
concentration of the specie of interest by calibration curves supplied with
the instrument. The operating ranges for the CO analyzer are 0-500 and
0-2000 ppm.
KVB 15900-524
21
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Specifications: Span Stability ±1% of full scale in 24 hours
Zero Stability ±1% of full scale in 24 hours
Ambient Temperature Range 32°F to 120°F
Line Voltage 115 ± 15 V rms
Response: 90% of full scale in 0.5 or 2.5 sec.
Precision: ±1% of full scale
Output: 4-20 ma
Carbon Dioxide concentration is measured by a Beckman Model 864
short path-length, non-dispersive infrared analyzer. This instrument measures
the differential in infrared energy absorbed from energy beams passed through
a reference cell (containing a gas selected to have minimal absorption of
infrared energy in the wavelength absorbed by the gas component of interest)
and a sample cell through which the sample gas flows continuously. The
differential absorption appears as"a reading on a scale from 0 to 100 and
is then related to the concentration of the specie of interest by calibration
curves supplied with the instrument. The operating ranges for the CX>2
analyzer are 0-5% and 0-20%.
Specifications: Span Stability ±1% of full scale in 24 hours
Zero Stability ±1% of full scale in 24 hours
Ambient Temperature Range 32 °F to 120°P
Line Voltage 115 t 15 V rms
Response; 90% of full scale in 0.5 or 2.5 sec.
Precision; ±1% of full scale
Output: 4-20 ma
The Oxygen content of the flue gas sample is automatically and
continuously determined with a Teledyne Model 326A Oxygen analyzer. Oxygen
in the flue gas diffuses through a Teflon membrane and is reduced on the
surface of the cathode. A corresponding oxidation occurs at the anode
internally and an electric current is produced that is proportional to the
concentration of oxygen. This current is measured and conditioned by the
instrument's electronic circuitry to give a final output in percent O2 by
volume for operating ranges of 0% to 5%, 0% to 10%, or 0% to 25%.
KVB 15900-524
22
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Specifications: Precision; ±1% of full scale
Response: 90% in less than 40 sec.
Sensitivity: 1% of low range
Linearity: tl% of full scale
Ambient Temperature Range: 32-125°F
Fuel cell life expectancy: 40,000%-hrs.
Power Requirement: 115 VAC, 50-60 Hz, 100 watts
Output: 4-20 ma
Hydrocarbons are measured using a Beckman Model 402 hydrocarbon
analyzer which utilizes the flame ionization method of detection. The sample
is drawn through a heated line to prevent the loss of higher molecular weight
hydrocarbons to the analyzer. It is then filtered and supplied to the
burner by means of a pump and flow control system. The sensor, which is
the burner, has its flame sustained by regulated flows of fuel (40% hydrogen
+ 60% helium) and air. In the flame, the hydrocarbon components of the sample
undergo a complete ionization that produces electrons and positive ions.
Polarized electrodes collect these ions, causing a small current to flow
through an electronic measuring circuit. This ionization current is pro-
port ion al to the concentration of hydrocarbon atoms which enter the burner.
The instrument is available with range selection from 5 ppm to 10% full
scale as
Specifications: Full scale sensitivity, adjustable from 5 ppm
to 10% CH4
• • Ranges: Range multiplier switch has 8 positions:
XI, X5, X10, X50, X100, X500, XlOOO, and X5000.
In addition, span control provides continuously
variable adjustment within a dynamic range of 10:1
Response Time: 90% full scale in 0.5 sec.
\
Precision: ±1% of full scale
Electronic Stability: ±1% of full scale for
successive identical samples
Reproducibility: ±1% of full scale for successive
identical samples
KVB 15900-524
23
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Analysis Temperature: Ambient
Ambient Temperature: 32°F to 110°F
Output: 4-20 ma
Air Requirements: 350 to 400 cc/min of clean,
hydrocarbon-free air, supplied at 30 to 200 psig
Fuel Gas Requirements: 75 to 80 cc/min of pre-mixed
fuel consisting of 40% hydrogen and 60% nitrogen
or helium, supplied at 30 to 200 psig
Electrical Power Requirements: 120v, 60 Hz
Automatic Flame-out indication and fuel shut-off valve
4.1.2 Recording Instruments
The output of the four analyzers are presented on front panel
meters and are simultaneously recorded on a Texas Instrument Model FLO4W6D
four-pen strip chart recorder. The recorder specifications are as follows:
Chart Size: 9-3/4 inch
Accuracy: io.25%
Linearity: <0.1%
Line Voltage: 120V 1 10% at 60 Hz
Span Step Response: 1 second
4.1.3 Gas Sampling and Conditioning System
The gas sampling and conditioning system consists of probes,
sample line, valves, pumps, filters and other components necessary to deliver
a representative, conditioned sample gas to the analytical instrumentation.
The following sections describe the system and its components. The entire
gas sampling and conditioning system shown schematically in Figure 4-1 is
contained in the emission test vehicle.
4.2 GASEOUS EMISSION SAMPLING TECHNIQUES
(NOx, CO, CO2, O2, HC)
Boiler access points for gaseous sampling are selected in the same
sample plant as are particulate sample points. Each probe consists of one-half
inch 316 stainless steel heavy wall tubing. A 100 micrometer Mott Metallurgical
Corp. sintered stainless steel filter is attached to each probe for removal of
particulate material.
24 KVB 15900-524
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10
ui
Figure 4-1. Flow schematic of mobile flue gas monitoring laboratory.
KVB 15900-524
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Gas samples to be analyzed for O2, CO2, CO and NO are conveyed
to the KVB mobile laboratory through 3/8 inch nylon sample lines. After
passing through bubblers for flow control, the samples pass through a dia-
phragm pump and a refrigerated dryer to reduce the sample dew point temperature
to 35°F. After the dryer, the sample gas is split between the various
continuous gas monitors for analysis. Flow through each continuous monitor
is accurately controlled with rotometers. Excess flow is vented to the
outside. Gas samples are drawn sequentially from all probes for each test.
The average emission values are reported in this report.
4.3 SULFUR OXIDES (SOx) MEASUREMENT AND PROCEDURE
Measurement of SO2 and 803 concentrations are made by wet chemical
analysis using the "Shell-Emeryville" method. In this technique the
gas sample is drawn from the stack through a glass probe (Figure 4-2),
containing a quartz wool filter to remove particulate matter, into a system
of three sintered glass plate absorbers (Figure 4-3). The first two absorbers
contain aqueous isopropyl alcohol and remove the sulfur trioxide| the third
contains aqueous hydrogen peroxide solution which absorbs the sulfur dioxide.
Some of the sulfur trioxide is removed by the first absorber, while the re-
mainder, which passes through as a sulfuric acid mist, is completely removed
by the secondary absorber mounted above the first. After the gas sample has
passed through the .absorbers, the gas train is purged with nitrogen to trans-
fer sulfur dioxide, which has dissolved in the first two absorbers, to the
third absorber to complete the separation of the two components. The isopropyl
alcohol is used to inhibit the oxidation of sulfur dioxide to sulfur tri-
oxide before it gets to the third absorber.
The isopropyl alcohol absorber solutions are combined and the
sulfate resulting from the sulfur trioxide absorption is titrated with
standard lead perchlorate solution using Sulfonazo III indicator. In a
similar manner, the hydrogen peroxide solution is titrated for the sulfate
resulting from the sulfur dioxide absorption.
KVB 15900-524
26
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Flue Wall
Asbestos Plug
Ball Joint
Vycor
Sample Probe
Pryoraeter
and
Thermocouple
Figure 4-2. SQx Sample Probe Construction
Spray Trap
Dial Thermometer
Pressure Gaugev \'
Volume Indies
tor
Vapor Trap
Diaphragm
Pump
Dry Test Meter
Figure 4-3. Sulfur Oxides Sampling Train
27
KVB 15900-524
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The gas sample is drawn from the flue by a single probe made of
quartz glass inserted into the duct approximately one-third to one-half way.
The inlet end of the probe holds a quartz wool filter to remove particulate
matter. It is important that the entire probe temperature be kept above
the dew point of sulfuric acid during sampling (minimum temperature of
260°C). This is accomplished by wrapping the probe with a heating tape.
Three repetitions of SOx sampling are made at each test point.
4.4 PARTICULATES MEASUREMENT AND PROCEDURES
Particulate samples are taken at the same sample ports as the
gaseous emission samples using a Joy Manufacturing Company portable effluent
sampler (Figure 4-4). This system, which meets the EPA design specifications
for Test Method 5, Determination of Particulate Emissions from Stationary
Sources (Federal Register, Volume 36, No. 27, page 24688, December 23, 1971),
is used to perform both the initial velocity traverse and the particulate
sample collection. Dry particulates are collected in a heated case using
first a cyclone to separate particles larger than 5 micrometers and a 100 mm
glass fiber filter for retention of particles down to 0.3 micrometers. Con-
densible particulates are collected in a train of four Greenburg-Smith
impingers in an ice water bath. The control unit includes a total gas meter
and thermocouple indicator. A pitot tube system is provided for setting
sample flows to obtain isokinetic sampling conditions.
All peripheral equipment is carried in the instrument van. This
includes a scale (accurate to ±0.1 mg), hot plate, drying oven (212°F), high
temperature oven, desiccator, and related glassware. A particulate analysis
laboratory is set up in the vicinity of the boiler in a vibration-free area.
Here filters are prepared, tare weighed and weighed again after particulate
collection. Also, probe washes are evaporated and weighed in the lab.
28
15900-524
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Heated Probe*
Sampling Nozzle
Reverse Type
Pitot Tube and
Gas Temp T/C
Control
Unit
Heated
Filter
Oven '
Filter Holder
T/C (Impinger
Out Temp)
T/C (Impinger
in Temp)
Check Valve
Velocity
Pressure
Gage (&P)
Impingers ^Ice Bath
Fine' Control Valve
Sample
Vacuum
Gage
Orifice
Gage (Ap)
Dry Test Meter '
Coarse
Control
Valve
Air-Tight
Pump
Umbilical
Cord
Figure 4-4. Particulate sampling train.
KVB 15900-524
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4.5 PARTICLE SIZE DISTRIBUTION MEASUREMENT AND PROCEDURE
The measurement of particle size distribution of the flyash is
performed using a Brink Model "B" Cascade impactor. The Brink impactor is
a five stage, low sample rate, cascade impactor suitable for measurements in
high mass loading situations. A schematic of the Brink sampling train is
shown in Figure 4-5,
Samples are pulled isokinetically from a single sample point. The
flow rate through the impactor is held constant during sampling to preserve
the impaction cut points.
Gelraan type A-E binderless glass fiber filter paper is used as
the collection substrate. The main purpose of the glass mats is to reduce
re-entrainment due to particle bounce. The 5/8 inch diameter mats are cut
from larger stock with a cork bore and inserted in the collection plates.
The collection plates with mats installed are desiccated 24 hours before
tare weighing. After sampling, all particles adhering to the impactor walls
are brushed down onto the collection plate immediately below. The plates
are again desiccated 24 hours before weighing.
The cyclone catch is brushed onto a tare weighed paper, desiccated
and weighed. The final filter, cut from the same fiber glass stock as the
collection plate substrates, is treated the same as the collection plates.
The sampling procedure is straight forward. First, the gas
velocity at the sample point is determined using a calibrated S-type pitot
tube. For this purpose a hand held particulate probe, inclined mano-
meter, thermocouple and 'indicator are used.
Second, a nozzle size is selected which will maintain isokinetic
flow rates within the recommended .02-.07 ft3/n>in rate at stack conditions.
Having selected a nozzle and determined the required flow rate for isokinetics,
the operating pressure drop across the impactor is determined from a cali-
bration curve. This pressure drop is corrected for temperature, pressure
and molecular weight of the gas to be sampled.
KVB 15900-524
30
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PRESSURE TAP
FOR 0-20" ^=^
KAGNAHELIX
CYCLONE
STAGE 1
STAGE 2
STAGE 3
STAGE 4
STAGE S
FINAL FILTER
EXHAUST
I
DRY GAS
METER
/ VACUUM \
I PUMP I
\^^S\
F1OW CONTROL
VALVE
DRYING
COLUMN
£;>.C:RICALLY HEATED PROBE
Figure 4-5. Brink cascade impactor sampling
train schematic.
KVB 15900-524
31
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The impactor is placed in the duct for 20-30 minutes prior to
sampling to allow it to be heated to stack temperature. During this warmup
period, the sample nozzle is turned away from the direction of gas flow so
that no particulates will be collected. Once hot, the stages are re-tightened
with pipe wrenches to prevent leakage. The impactor's nozzle is then turned
into the gas stream for collecting the particulate sample.
A sample is drawn at the predetermined AP for a time period which
is dictated by mass loading and size distribution. To minimize weighing
errors, it is desirable to collect several milligrams on each stage. However,
to minimize re-entrainment, a rule of thumb is that no stage should be loaded
above 10 mg.
The volume of dry gas sampled is measured with a dry gas meter.
This allows calculation of actual isokinetics. The dry gas volume is also
used to convert te'st results to concentration units. Stack moisture used
for calculating isokinetics is measured with the EPA Method 5 sample train
during concurrent particulate sampling.
Data reduction involves a time-consuming iterative process and
is best accomplished with the aid of a computer. For this purpose KVB
developed a 223 step program for the Texas Instruments SR-52 card program-
mable calculator. With this program, Brink data reduction can be easily
done in the field.
In addition to the Brink Cascade Impactor, particle sizing is
accomplished by several other methods. The SASS train utilizes three sized
cyclones and a final filter under controlled temperature and flow rates to
achieve gravimetric separation at ten, three and one micrometers.
Selected flyash samples are sent to an independent laboratory for
sizing using the BAHCO centrifugal classifier (PTC 28).
Each of the three particle sizing methods described above has its
advantages and disadvantages. None is ideal for the intended application.
32 KVB 15900-524
-------
Bahco - The Bahco classifier is described in Power Test Code 28.
It is an acceptable particle sizing method in the power industry and is often
used in specifying mechanical dust collector guarantees. Its main disad-
vantage is that it is a laboratory technique and is thus only as accurate
as the sample collected. Most Bahco samples are collected by cyclone separ-
ation; thus, particles below the cut point of the cyclone are lost. The
Bahco samples collected at Test Site B came from the cyclone in the EPA
Method 5 particulate train. These samples are spatially representative
because they were taken from a 24-point sample matrix. However, much of the
sample below about seven micrometers was lost to the filter. The Bahco
test data are presented in combination with sieve analysis of the same sample.
No attempt was made to correct for the lost portion of the sample.
Brink - The Brink cascade impactor is an in-situ particle sizing
device which separates the particles into six size classifications. It
has the advantage of collecting the entire sample. That is, everything down
to the collection efficiency of the final filter is included in the analysis.
Its disadvantages for this application are great. Because it is a single
point sampler, spatial stratification of particulate matter within the duct
will yield erroneous results. Unfortunately, the particles at the
outlets of stoker boilers may be considerably stratified. Another
disadvantage is its small classification range (0.3 to 3.0 micrometers) and
its small sample nozzle (1.5 to 2.0 mm maximum diameter). Both are inadequate
for the job at hand. The particles being collected at the boiler outlet are
often as large as the sample nozzle.
SASS - The Source Assessment Sampling System (SASS) was not designed
principally as a particle sizer but it includes three calibrated cyclones
which are used as such. The SASS train is a single point in-situ sampler.
Thus, it is on a par with cascade impactors. Because it is a high volume
sampler and samples are drawn through large nozzles (0.25 to 1.0 in.), it
has an advantage over the Brink cascade impactor where large particles are
involved. The cut points of the three cyclones are 10, 3 and one micrometers.
33 KVB 15900-524
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4.6 COAL SAMPLING AND ANALYSIS PROCEDURE
Coal samples are taken during each test from the units two
coal scales. The samples are processed and analyzed for both size consistency
and chemical composition. The use of the coal scale as a sampling station
has two advantages. It is close enough to the furnace that the coal sampled
simultaneously with testing is representative of the coal fired during the
testing. Also, because of the construction of the coal scale, it is possible
to collect a complete cut of coal off the scales apron feeder thus insuring
a representative size consist.
In order to collect representative coal samples, a sampling tray
having a twenty pound capacity was custom built. The tray has the same
width as the apron feeder belt and can be moved directly under the belts
discharge end to catch all of the coal over a short increment of time
(approximately five seconds).
Sampling procedure is as follows. At the start of testing one
increment of sample is collected from each feeder. This is repeated twice
more during the test (three to five hours duration) so that a six increment
sample is obtained. The sample is then riffled using a Gilson Model SP-2
Porta Splitter until two representative twenty pound samples are obtained.
The sample to be used for sieve analysis is weighed, dried in an
oven at 220°F for about four hours, and re-weighed. Drying of the coal is
necessary for good separation. If the coal is wet, fines cling to the
larger pieces of coal and to each other. Coal moisture removed by drying
represented 4-8 percent of the "as-fired" weight. Once dry, the coal is
sized using a six tray Gilson Model PS-3 Porta Screen. Screen sizes used are
1", 1/2", 1/4", #8 and #16 mesh. Screen area per tray is 14"xl4". The coal
in each tray is weighed on a triple beam balance to the nearest 0.1 gram.
The coal sample for chemical analysis is reduced to 2-3 pounds
by further riffling and sealed in a plastic bag. All coal samples are sent
to Commercial Testing and Engineering Company, South Holland, Illinois. Each
sample associated with a particulate loading or particle sizing test is given
a proximate analysis. In addition, selected samples receive ultimate analysis,
ash fusion temperature and mineral analysis of the ash.
KVB 15900-524
34
-------
During selected tests, coal samples composed of thirty-six
increments of six pounds each were collected along with the normal six
increment samples. These tests, reported in the appendix, demonstrated that
six increment samples were adequate for our purposes.
4.7 ASH COLLECTION AND ANALYSIS FOR COMBUSTIBLES
Combustible content of flyash is determined in the field by KVB
in accordance with ASTM D3173, "Moisture in the Analysis Sample of Coal and
Coke" and ASTM D3174, "Ash in the Analysis Sample of Coal and Coke."
The flyash sample is collected by the EPA Method 5 particulate
sample train while sampling for particulates. The cyclone catch is placed
in a desiccated and tare weighed ceramic crucible. The crucible with sample
is heated in an oven at 230°F to remove its moisture. It is then desiccated
to room temperature and weighed. The crucible with sample is then placed in
an electric muffle furnace maintained at a temperature of 1400°F until ignition
is complete and the sample has reached a constant weight. It is cooled in a
desiccator over desiccant and weighed. Combustible content is calculated
as the percent weight loss of the sample based on its post 230°F weight.
Bottom ash samples are collected from the bottom ash hopper within
two hours after completion of each test. The ash hopper is cleared just
prior to the test to insure that the hopper contains only ash generated during
the test. Four five-pound samples are collected representing a cross-section
of the ash hopper. These samples are mixed, quartered, and sent to Commercial
Testing and Engineering Company for combustible determination.
Multiclone ash samples are taken from four ports near the bottom
of the hopper into which the multiclone ash is dumped prior to being discarded.
This sample, approximately two quarts in size, is sent to Commercial Testing
and Engineering Company for combustible determination.
KVB 15900-524
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4.8 BOILER EFFICIENCY EVALUATION
Boiler efficiency is calculated using the ASME Test Form for Abbre-
viated Efficiency Test, Revised, September, 1965. The general approach to
efficiency evaluation is based on the assessment of combustion losses. These
losses can be grouped into three major categories: stack gas losses, combustible
losses, and radiation losses. The first two groups of losses are measured
directly. The third is estimated from the ABMA Standard Radiation Loss Chart.
Unlike the ASME test form where combustible losses are lumped into
one category, combustible losses are calculated and reported separately for
combustibles in the bottom ash, combustibles in the mechanically collected ash
which is not reinjected, and combustibles in the flyash leaving the mechanical
collector.
KVB has developed a program for the Texas Instrument's SR-52 card
programmable calculator to compute the above heat losses. Use of this program
helps minimize human error in the calculations.
4.9 MODIFIED SMOKE SPOT NUMBER
Modified Bacharach smoke spot numbers are determined using a
Bacharach field service type smoke tester. ASTM procedures for this measure-
ment apply only to oil fired units. Therefore, KVB has defined its own set
of procedures which differ from ASTM D2156-65 procedure in the number of
strokes taken with the hand pump. At this test site, one and two strokes
were taken at the boiler outlet.
Smoke spot measurements are obtained by pulling a fixed volume
of flue gas through a standard filter paper. The color (or shade) of the
spot that is produced is matched visually with a standard smoke spot
scale. The result is a "Smoke Number" which is used to characterize the
density of smoke in the flue gas.
The sampling device is a hand pump similar to the one shown in
Figure 4-6. It is a commercially available item that with ten strokes can
pass 2,250 ±100 cubic inches of gas at 60°F and 1 atmosphere pressure
through an enclosed filter paper for each 1.0 square inch effective surface
area of the filter paper.
36 KVB 15900-524
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Sampling Tabs
Filter Paper
Plunger
Handle
Figure 4-6. Field Service Type Smoke Tester
The standard smoke scale consists of a series of ten spots numbered
consecutively from 0 to 9, and ranging in equal photometric steps from white
through neutral shades of gray to black. The standard spots are imprinted
on white paper having an absolute surface reflectance of between 82.5 and
87.5%, determined photometrically. The smoke scale spot number is defined
as the reduction (due to smoke) in the amount of light reflected by a spot
divided by 10.
The smoke density is reported as the Smoke Spot Number of the spot
on the standard smoke scale that most closely corresponds to the color of
the soiled spot on the sample filter paper. Differences between two standard
Smoke Spot Numbers are interpolated to the nearest half number.
4.10
TRACE SPECIES MEASUREMENT
The EPA (IERL-RTP) has developed the Source Assessment Sampling
System (SASS) train for the collection of particulate and volatile matter
in addition to gaseous samples (Figure 4-7). The "catch" from the SASS train
is analyzed for polynuclear aromatic hydrocarbons (PAH) and inorganic trace
elements.
37
KVB 15900-524
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Convection
ovtn
Filter
Stick T.C.
Gas cooler
U)
00
Stick velocity (6P)
magnehellc gauges
Condensate
coltector
>"~"
Imp/cooler
trace element
• collector
Sorbent
cartridge
Implnger
T.C. "
Coarse adjustment
Fine
— « adjustwnt
valve
Vacuum pumps
\_
Vacuum
gage
Orifice AH*
•agnehellcjauqe
Dry test meter
Figure 4-7. Satire* Assasament Sampling System (SASS) flow diagram.
KVB 15900-524
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In this system, a stainless steel heated probe is connected to an
oven module containing three cyclones and a filter. Size fractionation is
accomplished in the series cyclone portion of the SASS train, which incor-
porates the cyclones in series to provide large quantities of particulate
matter which are classified by size into three ranges:
A) >10 ym B) 3 ym to 10 ym C) 1 ym to 3 ym
Together with a filter, a fourth cut (<1 ym) is obtained. Volatile organic
material is collected in an XAD-2 sorbent trap. The XAD-2 trap is an integral
part of the gas treatment system which follows the oven containing the cyclone
system. The gas treatment system is,.composed of four primary components:
the gas conditioner, the XAD-2 absorbent trap, the aqueous condensate collector,
and a temperature controller. The XAD-2 sorbent is a porous polymer resin
with the capability of absorbing a broad range of organic species. Some
trapping of volatile inorganic species is also anticipated as a result of
simple impaction. Volatile inorganic elements are collected in a series of
impingers. The pumping capacity is supplied by a 10 cfm high volume vacuum
pump, while required pressure, temperature, power and flow conditions are
obtained from a main controller.
4,11 FLYASH RESISTIVITY MEASUREMENT
The Wahlco Resistivity Probe is an in situ field device for use
in investigating problems with electrostatic precipitators. The means of
collection is mechanical so no dust characteristics are destroyed during the
sampling process. The probe can be used in temperatures up to 450°F. An
integral cleaning system allows repeated tests in a single location without
removing the probe from the duct. All instrumentation and probe hardware
are contained in a single carrying case suitable as a shipping container.
The Resistivity Probe consists of a small cyclone inserted in the
duct which collects a dust sample in a cylindrical stainless steel cup. A
high voltage discharge pin mounted axially and electrically insulated from
the cup serves as the energizing electrode. The steel cup serves as the
receiver. The high voltage supply is held at 1,000 volts and resistivity of
the collected sample is then determined as a function of the current.
39 KVB 15900-524
-------
An integral cleaning system permits emptying of the cup without
removing the probe from the duct. Air is blown through a separate tube to
a purge coil and then into the bottom of the cup, thus discharging the dust
back into the flue gas stream. The purpose of the purge coil is to pre-heat
incoming air to prevent condensation in the cup.
40
15900-524
-------
SECTION 5.0
TEST RESULTS AND OBSERVATIONS
This section presents the results of the tests performed on Boiler B.
Observations ^are made regarding the influence on gaseous and particulate
emissions and efficiency as the control parameters were varied.. A total of
33 tests were conducted in a defined test matrix to develop this data. Data
summary tables 5-10 through 5-19 are included at the end of this section
for reference.
5.1 OVERFIRE AIR
Overfire air flow rate was varied during four test sets to measure
this parameter's effects on boiler emissions and efficiency. Increasing the
rear overfire air flow resulted in reduced particulate emissions and increased
boiler efficiency. Gaseous emissions were not significantly affected. There-
fore, overfire air was demonstrated to be an effective emission control
technology for particulate emissions only, over the limited range of conditions
tested. These tests and their results are described in detail below. Test
conditions and results are summarized in Table 5-1.
As an initial step in understanding the overfire air system, its
air flow rate was measured and related to duct static pressure at two air
flow conditions. This information was then used to form the graph (Figure 5-1)
relating overfire air flow in Ib/min to static pressure at all flow conditions.
The basis for this relationship is Bernoulli's equation for fluid flow through
an orifice (in this case, the overfire air jets). One form of Bernoulli's
equation is:
AP Av2
p = 2g
Hero, AP is the pressure drop across an orifice, p is the fluid density,
is the change in fluid velocity and g is the gravitational constant. In
this relationship, velocity (v) is proportional to the square root of the
KVB 15900-524
41
-------
TABLE 5-1. EFFECT OF OVERFIRE AIR
ON EMISSIONS AND EFFICIENCY
Set 1
TEST MO.
OVERTIRE MR COM) IT IONS
Front OFA Pressure, "H2O (upper/lower)
Rear OFA Pressure, "H20 (upper/lower)
Overfire Air Flow. U>/min
Over fire Air, * of Total Air
'31
8/5
5/11
713
24
ii'
B/5
27/29
925
31
Set 2
1 5 £
is
8/5
5/10
712
19
ii'
B/S
24/27
903
24
Set 3
'•5 £
8/5
27/29
923
24
X < 1
8/20
24/27
••
"**
FIRING CONDITIONS
Coal Supplier*
Load, % of Capacity
Gr.ite Heat Release, 103BTD/ft2/hr
Coal Sizing, % passing 1/4'
Excess Air, %
BOILER OUTLET EMISSIONS
Particulate Loading, lb/106BTU
Conbustible Loading, lb/106BTU
Inorganic Ash Loading, Ib/lO^BTU
Combustibles in Flyash, »
02, % (dry)
CO, ppm (dry) * 3% 03
NO. ppn Idry) • 3« Oj
HULTICLOHE OQTLET EMISSIOI1S
R
49
400
27
59
9.6
6.0
3.5
62.6
8.0
36
280
R
48
377
19
69
7.2
4.6
2.6
64.0
8.8
96
339
H
72
564
36
41
12.3
6.5
5.7
53.3
6.3
103
209
H
73
557
21
46
9.2
5.1
4.1
55.2
6.8
34
310
ICC
79
576
20
42
11.7
6.7
5.0
57.3
6.4
44
311
KG
81
601
23
43
10.0
7.0
3.0
70.3
6.5
47
305
Particulate Loading,
Combustible Loading,
Inorganic Ash Loading, lb/106BTU
Coobustikles in Flyash, %
Nulticlone Collection Efficiency, *
ECONOMIZER OWLET
Flue Gas Temperature, *F
HEAT LOSSES. %
0.50
0.12
0.39
23.0
94.8
0.48
0.16
0.32
33.7
93.3
0.82
0.24
0.59
28.9
93.3
0.62
0.16
0.46
25.2
91.3
0.59
0.17
0.42
28.3
95.0
0.34
0.10
0.24
29.2
96.6
383
3B3
395
402
390
390
Combustibles in Multiclone catch
Coofaustibles in Emitted Flyash
Combustibles in Bottom Ash
Dry Gas Loss
Boiler Efficiency
3.61
0.17
0.14
8.80
80.27
3.15
0.25
0.08
9.63
80.32
6.64
0.39
2.02
7.61
76.36
3.84
0.26
0.34
8.82
79.89
4.41
0.30
0.04
8.05
80.48
4.84
0.16
0.80
7.68
79.78
• R - Reload
H - Hatfield
KC - Kentucky Cumberland
pressure drop (AP). Therefore, the overfire air flow rate in Ib/min should
be nearly proportional to the square root of the static pressure in the over-
fire air duct. The actual data for these calculations, and the formulas
used are given in Table A and B of the Appendix.
KVB 15900-524
42
-------
1000
950
900
850
fo
£ 800
750
700
600
SQUARE ROOT OF OVERFIRE AIR DRAFT, (in.H^O)
1/2'
Figure 5-1. Overfire air flow vs. OFA draft reading.
KVB 15900-524
43
-------
The air flow measurements were made with a S type pitot tube
using a 24-point traverse of the main overfire air duct. Only the rear over-
fire air flow was varied. As described in Section 3.2, most of the overfire
air enters the furnace through the two rear rows of overfire air jets. The
control dampers for the rear overfire air jets are remotely operable from the
panel board. The front row of jets, on the other hand, is set at a low
level and is not normally adjusted by the plant operating personnel. All
but one of the tests conducted on this unit (Test #28) were at overfire air
conditions near the two directly measured conditions. This adds validity
to the air flow determinations.
Participate emissions were reduced 25% by increasing the rear
overfire air flow as is shown in Figure 5-2. The reductions cannot be
attributed solely to burnout of combustibles in the flyash since both com-
bustibles and inorganic ash fractions were reduced proportionately the same.
During test set three where the front lower underfeeder air/tuyere cooling
air was increased, a 14.5% par tic ulate reduction was measured. In this case,
the reduction was completely attributable to a reduction in inorganic ash
loading. Attempts to vary the front upper overfire air flow failed be-
cause the damper was frozen in position (a result of not having been used).
A fourth test set (Tests 6 and 7) was rejected because firing conditions
could not be held constant.
The reduction in particulates and its constituents for the three
completed overfire air test sets are summarized below.
Set 1
Particulate Reduction, % -25
Combustible Fraction Reduction, % -23
Inorganic Ash Fraction Reduction, % -28
Nitric oxide emissions increased when overfire air flow through the
rear of the furnace was increased, but this increase may not be statistically
significant. The uncertainty, or scatter, in the data is graphically pre-
sented in Figures 5-3 and 5-4. Here, not only the overfire air test data but
other test data under similar firing conditions is presented. When the front
undergrate air flow was changed, the nitric oxide emissions remained unchanged.
KVB 15900-524
44
-------
14
12
10
COMBUSTIBLE P
INORGANIC ASH
FRACTION
"*«
a
•s-
a c>
£
Test 12 11
Test 22 21
Test 27 28
Figure 5-2.
Partxculate loading broken down into combustible and
inorganic fractions for three overfire air test sets
Test Site B.
45
KVB 15900-524
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400
678
EXCESS OXYGEN, % (DRY)
10
11
Figure 5-3. Nitric oxide emissions vs. excess oxygen at 500 to 600 x 10 BTU/ft -hr grate heat
release showing the reduction in nitric oxide concentration with reduced rear
overfire air-Test Site B.
KVB 15900-524
-------
400
(M
O
I
I
350
300
H
W
I 250
w
X
O
y
g 200
150
£]TEST 11, NORMAL OVERFIRE AIR
12, REDUCED REAR OVERFIRE AIR
OALL OTHER NORMAL OVERFIRE AIR TESTS
AT THE SAME LOAD AS TESTS 11 AND 12
D
I
I
6 7
EXCESS OXYGEN, % (DRY)
10
11
Figure 5-4. Nitric oxide emissions vs. excess oxygen at 300 to 400 x 10 BTU/ft -hr grate heat
release showing no significant reduction in nitric oxide concentration when the rear
overfire air flow is reduced - Test Site B.
KVB 15900-524
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Carbon monoxide emissions were negligible under both normal and
reduced overfire air conditions. Enough excess air and natural turbulance
was present at reduced overfire air conditions to prevent its formation.
Boiler efficiency increased when the rear overfire air flow was
increased. This increase was due to a decrease in combustible losses. The
efficiency increase due to reduced combustible loading at the boiler outlet
was 0.38% for set 1 and 2.93% for set 2. When the underfeeder air was in-
creased, the efficiency decreased 0.29%.
5.2 FLYASH REINJECTION
Flyash reinjection from the mechanical dust collector was reduced
20% during one test to determine this parameter's effect on particulate load
ingr particle size distribution, and boiler efficiency. The reduction in
reinjection rate resulted in a 39% reduction in particulate loading, and a
2.2% loss in boiler efficiency. Banco sizing of the flyash indicated that
the particulate reduction did not significantly affect the sub ten micrometer
particle concentration. A reinjection rate measurement was made but did not
produce results which would allow for a good ash balance.
5.2.1 Test 7, Reinjection Rate Measurement
Boiler B has no bypass valve or surge hopper for its reinjection
system. In order to stop reinjection for test purposes, it is necessary to
remove all the venturi sections from the reinjection lines and extend the
hopper downspouts into sealed barrels.
During Test No. 7, an attempt was made to do this with one of the
six boiler hopper reinjection lines and one of the seven mechanical collector
reinjection lines. Difficulties were encountered in removing the venturi
sections. Reinjection pressure was lost for approximately one-half hour,
resulting in several of the other reinjection lines plugging up.
Ash from the single boiler hopper reinjection line was collected at
a rate of 77.1 Ib/hr over a three-hour period. Thus, the total rate of ash
reinjection from the boiler hopper's six lines was calculated at 463 Ib/hr.
Certain errors could be expected in this measurement due to ash concentration
KVB 15900-524
48
-------
at one side of the hopper or various flow patterns. If the measured rate is
representative of all six reinjection lines, then the boiler hopper removed
fifteen percent of the boiler outlet flyash.
Ash from the single mechanical dust collector downspout was collected
at a rate of 17.1 Ib/hr over a 2-1/2 hour period. Thus, the l;otal rate of ash
reinjection from the mechanical dust collector was calculated to be 120 Ib/hr.
This measurement suffers from the same difficulties as the measurement of the
boiler hopper reinjection rate. The line may also have been partially plugged.
As shown in Figure 5-5, if 60% of the mechanically collected flyash were rein-
jected (design rate), the reinjection rate would be on the order of 1084 Ib/hr,
or twelve times the measured rate.
These measurements did not produce results which would allow for a
good ash balance. A good ash balance would include measuring the ash flows
from all reinjection lines simultaneously. Such a test was not included in the
scope of work for this program. At Site B, this would have required a level
of effort and additional expense which was not justifiable at the time of these
tests.
5.2.2 Test 23, Reduced Reinjection
During Test 23, the mechanical dust collector reinjection rate was
reduced, and emissions were measured. The reduction was accomplished by
extending a pipe from the bottom of each reinjection line into a sealed drum.
Reinjection air pressure was reduced to near zero but the lines were not
capped off. Therefore, some of the ash was reinjected and some was collected
in the drums. In this manner, the reinjection rate was reduced without dis-
mantling the reinjection hardware.
Ash was collected at a rate of 460 Ib/hr over a 2-1/2 hour period.
This represents 30% of the calculated normal reinjection rate {see Figure 5-5),
or a 30% reduction in the reinjection rate from the mechanical dust collector.
Test 25 was run under similar conditions as Test 23 except that fly-
ash reinjection was not reduced. The emissions and efficiency of these two
tests are compared in Table 5-2. Test 23 (reduced reinjection) resulted in a
39% lower particulate loading at the boiler outlet and a 19% lower particulate
loading at the collector outlet than Test 25, but also resulted in a 2.2%
KVB 15900-524
49
-------
FURNACE
TEST 7
REINJECTION RATE
MEASUREMENT
Steam Flow
151,700 Ib/hr
Coal Flow
18,300 Ib/hr,
Boiler
Hopper
Segregating
D.C. Hopper
976 17
TEST 23
REDUCED REINJECTION
Steam Flow
197,900 Ib/hr
Coal Flow
21,600 Ib/hr
1030 460
TEST 25
NORMAL REINJECTION
Steam Flow
200,400 Ib/hr
Coal Flow
22,600 Ib/hr
1774
Figure 5-5. Fly ash flow rates for different reinjection
configurations. Test Site B. All numbers are
mass flow rate in Ib/hr.
KVB 15900-524
50
-------
TABLE 5-2. EFFECT OF FLY ASH REINJECTION
ON EMISSIONS AND EFFICIENCY
Test No. 23 Test No. 25
Fly Ash Reinjection Rate Reduced 20% Normal
FIRING CONDITIONS
Coal Supplier Kentucky Cumberland Kentucky Cunberland
Load, % of Capacity 99 100
Grate Heat Release, 10 BTU/ft /hr 764 791
Coal Sizing, % passing 1/4" 36 25
Excess Air, % 34 32
BOILER OUTLET EMISSIONS
Particulate Loading, lb/10gBTU 9.59 15.75
Combustible Loading, lb/10 BTU 5.84 7.40
Inorganic Ash Loading, lb/10 BTU 3.75 8.35
Combustibles in Fly Ash, % 60.9 47.0
02, * (dry) 5.5 5.3
CO, ppm (dry) @ 3% 0. 41 60
NO, ppm (dry) @ 3% Q 254 317
MULTICLONE OUTLET EMISSIONS
6 0.485 0.596
Particulate Loading, lb/10 BTU
Combustible Loading, lb/10 BTU 0.129 0.149
Inorganic Ash Loading, Ib/lO^TU 0.356 0.447
Combustibles in Fly Ash, % 26.7 25.0
Multiclone Collection Efficiency, % 94.9 96.2
HEAT LOSSES, %
Dry Gas Loss
Moisture in Fuel
H2O from Combustion of H_
Combustibles in Collected Fly Ash
Combustibles in Emitted Fly Ash
Combustibles in Bottom Ash
Radiation Loss
Unmeasured Losses
Total Losses
Boiler Efficiency
7.96
0.52
4.42
8.09
0.24
1.01
0.38
1.50
23.85
76.15
7.66
0.27
4.21
6.76
0.24
0.64
0.38
1 .50
21.66
78.34
KVB 15900-524
51
-------
Ul
10
10 30
MIDPOINT PARTICLE
100 300
DIAMETER (Ad), Micrometers
1000
Figure 5-6. Particle size concentrations for boiler outlet participates under normal and
reduced fly ash reinjection conditions - Test Site B.
KVB 15900-524
-------
lower boiler efficiency. One and one-third percent of this efficiency reduction
represents the heating value of the 20% flyash not reinjected. The remaining
0.9% may be due to factors not related to the reduced reinjection.
Particle size concentrations for both tests are shown in Figure
5-6. This data shows that the largest changes in mass concentration occurred
above ten micrometers in size.
5.3 EXCESS OXYGEN AND GRATE HEAT RELEASE
Boiler B was tested for emissions and efficiency over a full range
of loads and excess air conditions. The results of these tests are discussed
below. In this discussion, boiler loading is expressed in terms of grate
heat release to be more directly relatable to other units.
5.3.1 Excess Oxygen Operating Levels
Excess oxygen operating levels are an important characteristic of a
boiler. As excess air is lowered, the dry gas loss (or heat lost out the
stack) drops. The lower limit is set by the onset of smoke, excessive CO,
or clinkering on the grate.
Figure 5-7 shows the oxygen levels at which emissions and efficiency
were measured on Boiler B. The shaded area illustrates how the excess air
requirement drops as the heat release rate increases. The boundaries shown
do not necessarily represent acceptable operating conditions because the tests
were of short duration (i.e., 2 to 3 hours). Problems such as clinker and
slag formation often require more time to develop.
5.3.2 Particulate Loading vs. Excess Oxygen and Boiler Load
Test data show that particulate loading increases with grate air
velocity. The velocity is a function of both excess air and boiler load. This
relationship is shown in Figure 5-8.
The variable excess oxygen can be isolated from this data by
examining three test sets. Each test set consists of two particulate tests
run within-27 "hours of each other in~which excess oxygen is the only controlled
variable. The firing conditions and resulting emissions for these tests are
presented in Table 5-3. The data show a significant increase in particulate
53 KVB 15900-524
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14
12
10
ui
g
I
(0
PARTICULATE LOADING TESTS
OTHER TESTS
I
I
I
100
200
Figure 5-7.
300 400 500 600
GRATE HEAT REUEASE. 103BTU/ft2-hr
700
800
900
Excess oxygen operating levels vs. grate heat release for all tests run at
Test Site B. Shaded area represents normal operating range for the stoker.
KVB 15900-524
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18
U1
16
J
o
I
12
10
O
ffl
O ALL BOILER OUTLET PARTICULATE TESTS
REDUCED FLX ASH REINJECTION TEST
0.4
I
I
0.8
2.4
2.8
1.2 1.6 2.0
GRATE AIR VELOCITY, FT/SEC
Figure 5-8. Relationship between grate air velocity and particulate loading at Test Site B.
KVB 15900-524
3.2
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TABLE 5-3. EFFECT OF EXCESS OXYGEN
ON EMISSIONS AND EFFICIENCY
TEST SITE B
TEST HO.
FIRING CONDITIONS
Coal Supplier*
Load, % of Capacity , ,
Grate Heat Release, 10 BTO/ft -hr
Coal Siring, « passing 1/4"
Excess Air, %
BOILER OUTLET EMISSIONS
Participate Loading, lb/lo|BTO
Combustible Loading, lb/10 BTU
Inorganic Ash Loading, lb/106BTU
Combustibles in Fly Ash, %
02. t (dry)
CO, pp» (dry) 9 3» O.
HO, pp» (dry) e 3% Oj
MOLTICLONB OUTLET EMZSSIOHS
Particulate Loading, Ib/lO^BTO
Combustible Loading, lb/10 BJD_
Inorganic Ash Loading, Ib/lOTITU
Combustibles in Fly Ash, t
Molticlone Collection Efficiency, %
HEAT LOSSES, %
Dry Gas Loss
Moisture in Fuel
H2O from Combustion of H2
Combustibles in Collected Fly Ash
Combustibles in Emitted Fly Ash
Radiation Loss
Unmeasured Losses
Total Losses
Boiler Efficiency
Set
|
So
9E
xc
75
571
21
69
15.5
9.3
6.3
59.7
10.2
25.0
306.0
0.63
0.13
0.70
15.40
94.60
12.00
0.40
4.11
3.04
0.19
O.SO
1.50
22.38
77.62
1
|
3s
KC
73
592
28
46
6.2
5.0
3.1
61.6
6.9
120.0
237.0
O.S2
0.11
0.40
21.90
93.70
8.32
0.45
4.23
2.85
0.17
0.52
1.50
19.11
80.69
Set
1
f "
I
KC
73
548
28
46
10.8
7.0
3.8
65. 1
6.8
35.0
332-0
0.56
0.16
0.40
28.00
94.80
8.26
0.46
4.41
6.53
0.27
0.51
1.50
22.36
77.61
2
1
3s
KC
75
564
25
28
10.5
6.3
4.2
62.0
4.7
35.0
239.0
0.56
0.16
0.40
28.80
94.70
7.93
0.32
4.20
5.38
0.28
0.49
1.50
20.64
79.36
Set
|
So
s
R
89
675
35
47
14.6
11.0
3.7
74.9
7.0
48.0
294.0
0.023
—
—
— —
8.34
0.61
4.15
—
—
0.42
1.50
—
~
3
I
3s
R
87
675
29
25
12.5
8.6
3.9
69.0
4.3
27.0
215.0
0.018
—
—
— -
6.53
O.SO
4.14
~
~
0.43
1.50
—
~
*KC - Kentucky Cumberland Coal
R Coal reloaded from dead storage
KVB 15900-524
56
-------
loading for the first test set but only small increases for sets 2 and 3.
The large particulate increase in the first set may be attributable to the
fact that the high excess oxygen test (Test No. 8) was well outside the
normal operating range at the test load. The normal operating range was
defined in Figure 5-7 to be 4.6% to 7.6% O2 whereas Test 8 was run at 10.2%
02- Taking this into consideration, excess oxygen is not, by itself, a very
effective control technique for particulate reduction on Boiler B.
Particulato loading at the boiler outlet is plotted against grate
heat release in Fiqure 5-9. Limits are included to define the data trend.
At the design grate heat release, particulate loadings range between 12 and
16 Ibs of particulate matter per million BTU of coal burned at the boiler outlet.
5.3.3 Carbon Monoxide vs Excess Oxygen andBoiler Load
The carbon monoxide data from all tests is plotted against excess
oxygen in Figure 5-10. Carbon monoxide was insignificant at all high load
test conditions including the maximum rating on the unit. At low loads, carbon
monoxide increased with increasing excess oxygen. The test point at 14% C»2 was
an unrealistic firing condition created only for test purposes. Thus, carbon
monoxide concentrations remained insignificant throughout the load and excess
oxygen operating range of this boiler.
5.3.4 Combustibles vs Excess Oxygen and Boiler Load
Combustibles in the boiler outlet flyash were found to be independent
of excess oxygen and slightly dependent on boiler load. The dependency on
boiler load is shown in Figure 5-11. In this figure, it appears that combus-
tibles rise slowly with increasing heat release rate and then drop again
at peak boiler load. This dependency is so slight as to be statistically
insignificant. The average and standard deviation combustible content of the
boiler outlet flyash was 60.3 - 7.1%.
Combustibles in the bottom ash are shown plotted against excess
oxygen in Figure 5-12. No correlation is evident in the data with either boiler
load or excess oxygens The average and standard deviation of this data is
12.4 i 7.0%. In absolute limits, the combustible content varied from 4.0% to
25.8%.
57 KVB 15900-524
-------
18
ui
00
16
(0
I
, 14
I
12
o
H
10
O
03
8
• KENTUCKY CUMBERLAND COAL
O HATFIELD COAL
A SOUTHEAST COAL
A RELOAD COAL FROM DEAD STORAGE
EXCESSIVELY
HIGH O,
REDUCED
RE INJECTION
100
Figure 5-9.
200
300 400 500 , 600
GRATE HEAT RELEASE, 10 Btu/ft *-hr
700
800
900
Particulate loading at the boiler outlet vs. grate heat release and coal type.
Shaded area is shown to emphasize trend - Test Site B.
KVB 15900-524
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1000
U1
to
800
o"
PO
_ 600
a
e
a
g 400
o
z
| 200
GRATE HEAT RELEASE
103 BTU/ft2-hr
J^ 700-799 (100% LOAD)
9 600 - 699 (90% LOAD)
Q 500- 599 (80% LOAD)
O 300 - 399 (50% LOAD)
V 200 - 299 (30% LOAD)
D
D
ID
6 8 10
EXCESS OXYGEN, % (DRY)
12
14
16
Figure 5-10. Carbon monoxide emissions vs. excess oxygen and grate heat release - Test Site B,
KVB 15900-524
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100
K
2
a
80
o
o
60
o
to
5 40
9>
1
u
20
100
I
I
I
200 300 400 500
GRATE HEAT RELEASE, 10 BTU/£t2-hr
600
700
800
Figure 5<-ll. Combustible content of the boiler outlet fly ash vs. grate heat release - Test
Site B.
KVB 15900-524
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100
80
60
Z
M
40
20
O ^r?
O CP
O O
o
-------
5.3.5 Nitric Oxide vs. Excess Oxygen and Boiler Load
The nitric oxide data is presented in three graphs. Figure 5-13
presents all the nitric oxide data from Boiler B as a function of excess
oxygen. Data points are differentiated by load, and solid lines connect
those test sets (Test Nos. 10, 13, and 14) which were designed specifically
to find the relationship between NO and O,. Figure 5-14 presents the nitric
oxide trend lines based on the data points in Figure 5-13. Figure 5-15
presents the nitric oxide data as a function of boiler load for all tests.
The following observations are made:
1. Nitric oxide concentration increases an average of
30 ppm for each one percent increase in O. at constant
boiler load.
2. Nitric oxide concentration increases an average of
20 ppm for each 10% increase of boiler load at con-
stant excess O_.
3. The average nitric oxide concentration is 270 ppm
with 90% of all measured data falling within the
limits of 227 to 312 ppm at all loads. The counter
effects on nitric oxide formation of decreasing
excess air with increasing boiler load nearly cancel
each other out on this boiler, resulting in a fairly
stable emission profile over the full load range.
5.3.6 Boiler Efficiency vs. Excess Oxygenand Boiler Load
Boiler efficiency was calculated by the ASME Heat Loss Method
for each test which included measurement of particulate loading at the
mechanical dust collector outlet. The measured heat losses are summarized
in Table 2-3. Boiler efficiencies are graphically displayed as a function
t
of grate heat release in Figure 5-161 and the dry gas heat loss is plotted
against excess oxygen in Figure 5-17.
KVB 15900-524
62
-------
U)
500
o
0
1
400
i 300
8
o
M
W
SB 200
W
i
U
M
z
100
GRATE HEAT RELEASE,
103 BTU/£t2-hr
°o
I
I
I
6 8 10
BXCESS OXTGMJ, % (DRY)
12
14
16
Ftgure 5-13. Nitric c»«ide concentration vs. excess oxygen and grate heat release - Test Site B.
KVB 15900-524
-------
500
"
400
I
I300
W
W
200
§
o
100
100 90 80 70 50 30
BOILER LOAD, % DESIGN CAPACITY
I
I
6 8 10
EXCESS OXYGEN, % (DRY)
12
14
16
Figure 5-14.
Nitric oxide trend lines as a function of excess oxygen and boiler load - Test
Site B.
KVB 15900-524
-------
I/I
500
o"
i
H
0}
a
400
300
200
100
100
O
o
O
o
200
300
400
500
600
700
800
3 2
GRATE HEAT RELEASE, 10 BTU/ft -hr
900
Figure 5-15. Nitric oxide emissions vs. grate heat release for all test conditions - Test Site B.
KVB 15900-524
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0*
90
85
80
70
65
100
i-
200
o o
o
o
I" I
o
o
300 400 500 . 600
GRATE HEAT RELEASE, 10 BTD/ft -hr
700
800
900
Figure 5-16. Boiler efficiency vs, grate heat release for all tests - Test Site B.
KVB 15900-524
-------
12
ii
678
EXCESS OXYGEN, % (DRY)
10
Figure 5-17. Dry gas heat loss vs. excess oxygen for all test conditions - Test Site B.
KVB 15900-524
-------
The following observations are made:
1. The measured boiler efficiency varied between a low
of 75.5% and a high of 80.9%.
2. Boiler efficiency did not vary significantly with
boiler load tgrate heat release); see Figure 5-16.
3. Boiler efficiency increased with decreasing excess
air. A one percent reduction in excess oxygen resulted
in about a 0.6% reduction in dry gas heat loss; see
Figure 5-17.
5.4 COAL PROPERTIES
Coals from four sources were test fired in Boiler B. These coals
varied very little in their properties, and as a result, boiler emissions
and efficiency were not significantly affected by the coal selection. Par-
ticulate loading, particle size distribution, nitric oxide emissions, carbon
monoxide emissions, and conbustible content of the ash were unchanged by
coal selection.
The "as-fired" proximate analysis of the four test coals are
given in Tables 5-14 through 5-17, and are summarized in Table 3-2. Table
5-3.2 "Summary of Percent Combustibles in Refuse" and Table 5-13 "Coal Sizing
Summary" group data by coal type and further illustrate the similarities
in the test coals.
Coal size consistency was an uncontrolled variable at Test Site
B. It is believed to have an impact on particulate emission levels. There-
fore, coal size consistency was measured for each test and examined along
with other variables.
The average and standard deviation of each coal's size consist-
ency are compared with the ABMA recommended limits of coal sizing for spreader
stokers in Figures 5-18 through 5-21. Two observations are made:
1. Each of the four test coals lies generally within the
ABMA recommended limits of coal sizing.
KVB 15900-524
68
-------
nded limits
for
stokers
race
coal
spteader
Average
deviati
Cunfcerl
and star Hard
in of Kentucky
ind ooal Uixe
50#
16# 8# 1/4" 1/2"
SIEVE SIZE DESICCATION
Figure 5-18.
Size consistency of "as-fired" Kentucky Cumberland
coal vs. ABMA recommended limits of coal sizing for
spreader stokers - Test Site B.
KVB 15900-524
69
-------
A3MA
of coal s:
a Dreader s
recoi mended
zing for
tokers
and standard
on of Hai
consii
Average
deviati
coal
:field
tency
50f
16#
8# 1/4"
SIEVE SIZE DESIGNATION
Figure 5-19.
Size consistency of "as-fired" Hatfield coal vs.
ABHA recommended limits of coal sizing for spreader
stokers - Test Site B.
KVB 15900-524
70
-------
1A
coal
reader stbkers
and standard
of Sov
consis
1/4" 1/2"
SIEVE SIZE DESIGNATION
1"
Figure 5-20.
Size consistency of "as-fired" Southeast coal vs.
ABMA recommended limits of coal sizing for spreader
stokers - Test Site B.
KVB 15900-524
71
-------
ABMA
of coal
spreader
recommended
sizing for
stokers
age and
ation of
dead storage
standard
coal
consist ancy
8# 1/4" 1/2"
SIEVE SIZE DESIGNATION
1"
Figure 5-21.
Size consistency of "as-fired" coal from dead
storage vs. ABMA recommended limits of coal sizing
for spreader stokers - Test Site B.
KVB 15900-524
72
-------
2. The four test coals are very similar in size consistency.
The fact that the four coals were very similar in size consistency was helpful
because it eliminated one uncontrolled variable during testing. The small
natural variations in sizing did not noticeably affect emissions. The only
operational problem posed by these coals occurred when they were wet and the
fines piled in front of the feeders instead of burning in suspension.
5,5 PARTICLE SIZE DISTRIBUTION
A total of 21 particle size distribution tests were run at Test Site
B. Both in-situ and laboratory methodology were used. The tests run and
methodology used are shown in Table 5-4.
A brief description of the three particle sizing methods used is
helpful in understanding the data. The descriptions are given in Section 4.5.
The particle size distribution data are plotted on Figures 5-22,
5-23, and 5-24, Each graph represents all the particle sizing data for one
particle sizing method. All of the test data are presented in Table 5-5.
This table organizes the data by sample location, sample method, boiler load,
and coal source. The table presents the three micrometers and ten micrometers
cut points (percent of particulate matter below these sizes) for each test.
Evidence of a relationship between particle size distribution and
such variables as boiler load, excess oxygen, and coal selection is incon-
clusive. However, the data should be helpful to the designers of particulate
removal equipment. Commentary on several of the relationships examined is
given below.
Coal Selection - No relationship was demonstrated between coal sel-
ection and particle size distribution. Referring to Table 5-5, at 100% load,
the three coals appeared identical on the Bahco analysis. The SASS tests
showed a reverse in the trend at 100% and 78% loads. At 100% load, Kentucky
Cumberland had the greatest percentage of particulates below 10 micrometers,
while at 78% load it had the least percentage.
73 KVB 15900-524
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TABLE 5-4. PARTICLE SIZE DISTRIBUTION TESTS
AND METHODOLOGY USED." - TEST SITE B
Particle Size Distribution
Methodology Used
Test
No.
4
5
6
7
15
16
23*
24
25
26
30
31
33
Coal*
K
H
S
S
R
R
K
S
K
H
H
K
S
Load
%
47
47
75
76
87
89
99
99
100
99
78
77
79
Multiclone
Boiler Outlet Outlet
Bahco — -
Brink
— SASS
SASS
SASS —
SASS
Bahco —
Bahco, SASS Brink
Bahco, SASS Brink
Bahco, SASS Brink
SASS
SASS —
SASS
ESP Outlet
—
mm mm
_
—
SASS
SASS
—
—
—
—
—
—
—
*K - Kentucky Cumberland coal
H - Hatfield coal
S - Southeast coal
R - Reload coal from dead storage
Reduced reinjection test
KVB 15900-524
74
-------
H
I
u
cu
99.99
99.9
99
95
80
70
50
30
20
10
5
2
1
0.5
0.2
0.1
0.01
10 30 100 300
EQUIVALENT PARTICLE DIAMETER, MICROMETERS
Figure 5-22. Bahco classifier and sieve analysis particle distribution - Test Site B.
1000
3000
KVB 15900-524
-------
99.99
99.9
W
N
H
§
H
EH
Cfl
a
w
w
CU
0.01
0.3 1 3
EQUIVALENT PARTICLE DIAMETER, MICROMETERS
Figure 5-23. Brink cascade impactor particle size distribution, Test
Site B.
KVB 15900-524
76
-------
H
WJ
g
g
Pu
99.99
99.9
99
98
95
90
80
70
60
50
40
30
20
10
5
2
1
0.
,01
0
Multiclone :.. T-pT^&P
1 3 10
EQUIVALENT PARTICLE DIAMETER, MICROMETERS
Figure 5-24. SASS gravimetric particle size distribution - Test
Site B.
KVB 15900-524
77
-------
TABLE 5-5. PARTICLE SIZE DISTRIBUTION TEST RESULTS -
TEST SITE B
Sample Location
Load
% Coal*
% Participates Below:
3 micrometers/10 micrometers
Banco
Brink
SASS
Boiler Outlet
1.5/6f 1.8/8f
1.4/6
1.5/6
3.2/14
Multiclone
Outlet
ESP Outlet
100
78
88-
X
B
S
-S
•R
6.2/NA
48/NA
35/NA
44/NA
11.3/39
9,3/30
6.3/23
5.6/20, 5.6/191
2,7/12
3.1/12
4.8/15
41/78
87/89f 85/94*
*K - Kentucky Cumberland coal
H - Hatfield coal
S - Southeast coal
R - Reload coal 'from dead storage
Normal fly ash rein ject ion, reduced fly ash reinjection
4.3%
7.0%
JC7B 15900-524
78
-------
Boiler Load - No consistent relationship was demonstrated between
boiler load and particle size distribution. In the Banco tests, the low
load evidenced a shift toward smaller particles. In the SASS tests, the
reverse was true.
Excess Oxygen - Data is insufficient to draw any conclusions. At
88% load, SASS tests were run at the boiler outlet and at the ESP outlet.
At the boiler outlet the sizing results were nearly identical. However,
the low O2 test showed a greater percentage below one micron than the high
O2 test.
Sample Location - Boiler outlet particulates ranged from 1.5% to
11.3% below 3 microns. Multiclone outlet particulates ranged from 35% to
48% below 3 microns. ESP outlet particulates were 85% and 87% below 3
microns.
Sample Method - Banco tests showed the lowest concentrations of
particulates below 10 microns. This is due to the sample portion lost to
the EPA Method 5 filter. Brink and SASS tests appear to yield similar
results.
Fly Ash Reinjection - The reduced reinjection test showed a shift
in particle size to the smaller particles. This shift was small in magnitude.
5.6 EFFICIENCY OF POLLUTION CONTROL EQUIPMENT
The emission control equipment of Unit B consisted of a selective
type multiclone dust collector and an electrostatic precipitator (ESP). The
mechanical dust collector is a UOP Design 104 dynamic centrifugal collector
with 140 ten in. collection tubes. Its guaranteed collection efficiency is
90% based on an inlet dust analyzing 10% less than 10 microns. Actual mea-
surements (Table 5-6) showed the collector efficiency to range from 92.7%
to 96.6% with an average efficiency of 94.6%. Inlet dust analysis during
these tests was 6% less than 10 microns based on Bahco analysis, and 12% to
39% less than 10 microns based on SASS gravimetric data. Thus, the mechan-
ical DC performance was found to be well within guaranteed limits.
KVB 15900-524
79
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TABLE 5-6. EFFICIENCY OF POLLUTION CONTROL EQUIPMENT
oo
o
Test
No.
3
4
6
7
8
9
11
12
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Load
27
47
75
76
75
73
48
49
87
89
88
74
75
73
73
72
99
99
100
99
79
81
Particulate Loading
09 lb/106 BTU
%
10.9
8.0
5.2
4.4
10.2
6.9
8.8
8.0
4.3
7.0
6.6
6.5
4.7
6.8
6.8
6.3
5.5
5.1
5.3
5.3
6.4
6.5
Equipment
Multiclone D,C.
n n
n n
n n
n n
II W
ii it
II 19
Multiclone & ESP
„
Multiclone D.C.
n n
n n
n »
n n
n n
N II
n n
n n
N II
w n
n n
Inlet
10.32
9.65
11.65
10.28
15.51
8.16
7.21
9.57
12.53
14.63
10.66
12.76
10.53
10.81
9.25
12.27
9.59
13.88
15.75
12.67
11.75
9.98
Outlet
0.543
0.446
0.469
0.755
0.830
0.518
0.481
0.500
0.023
0.018
0.467
0.810
0.563
0.561
0.619
0.824
0.485
3.53
0.596
0.035
0.591
0.343
Efficiency
94.7
95.4
96.0
92.7
94.6
93.7
93.3
94.8
99.82
99.88
95.6
93.7
94.7
94.8
93.3
93.3
94.9
74.6
96.2
95.0
95.0
96.6
Remarks
Severe clinkering
Reduced OFA
Reduced OFA
Bottom ash pulled
during test
Reduced OFA
Reduced reinjection
Reduced OFA
KVB 15900-524
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Efficiency of the ESP was not measured directly. Instead, the com-
bined efficiency of the mechanical DC and the ESP were measured twice. The
results, shown on Table 5-6, were 99.82% and 99.88%. If an ESP inlet loading
of 0.50 lb/10 BTU is assumed, the ESP efficiencies become 95.4% and 96.4%
for the two tests.
"-.. » f
The effect of combustion variables on the mechanical D.C. collection
efficiency were not significant. As shown in Figure 5-25, the different
coals all produced similar efficiencies. Excess air, overfire air, and even
inlet velocity had very little discernable effect on the collection effi-
ciency. Scatter in the data cannot be resolved by the known variables.
Figure 5-26 presents the multiclone outlet particulate loading as
a function of grate heat release and coal selection. Neither of these vari-
ables shows any discernable relationship to particulate loading after the
collector. Average loading was 0.58 lb/10 BTU. During three tests out of
19, the loading was above 0.80 lb/10 BTU.
5.7 MODIFIED SMOKE SPOT NUMBER
Smoke spot readings were taken with a Bacharach smoke spot tester
at the boiler outlet. The pump was stroked once or twice each time as
opposed to the specified ten times required on an oil-fired unit by ASTM
D2156-65. The smoke spot results are tabulated in Table 5-7. They are
plotted against particulate loading in Figure 5-27, and against combustible
loading in Figure 5-28.
•• The purpose-of this exercise was to develop a quick and easy method
of estimating either particulate loading or combustible loading from stoker-
fired boilers. It is observed in Figures 5-27 and 5-28 that no correlation
could be made.
Based on this data, the modified smoke spot technique is not a
useful method for estimating particulate or combustible loadings at the
boiler outlet of spreader stokers. A primary reason is its inability to
collect on filter paper the large particles which contain the majority of
the particulate and combustible mass.
KVB 15900-524
81
-------
oo
to
100
95
6
u
90
e< 85
80
75
100
• Kentucky Cunberland coal
O Hatfield coal
A Southeast coal
A Reload coal from dead storage
200
300
400
500
600
700
800
900
GRATE HEAT RELEASE, 103 BTU/ft2-hr
figure 5-25. Hulticlone dust collector efficiency vs. grate heat release and coal selection
Test Site B.
XVB 15900-524
-------
1.0
n
\o
0.8
u
£ Kentucky Cumberland coal
O Hatfield coal
A Southeast coal
A Reload coal from dead storage
0.6
0.4
0.2
A
100
Figure 5-26.
200
300
400
500
600
700
800
900
GRATE HEAT RELEASE, 103 BTU/ft2-hr
Multlclone outlet particulate loading vs. grate heat release and coal selection -
Test Site B.
KVB 15900-524
-------
TABLE 5-7. MODIFIED SMOKE SPOT DATA
TEST SITE B
Test
No.
3
4
6
8
9
11
12
17
18
19
20
21
22
23
24
25
26
27
28
Avg Reading
1 Pump
8.0
4.0
2.5
2.5
4.0
2.8
4.5
1.5
2.5
4.5
3.0
2.0
6.5
1.5
2.5
3.0
4.0
2.0
4.3
Avg Reading
2 Pumps
6.5
3.8
3.0
5.2
4.8
6.0
3.0
4.3
6.5
4.5
3.5
8.5
2.8
4.0
5.8
5.0
3.5
4.8
P articulate
Loading
lb/106 BTU
10.3
9.7
11.7
15.5
8.2
7.2
9.6
10.7
12.8
10.5
10.8
9.2
12.3
9.6
13.9
15.8
12.8
11.7
10.0
Combustible
Loading
lb/106 BTU
4.5
5.3
4.7
5.0
4.9
4.6
6.0
6.7
8.2
6.5
7.0
5.1
6.5
5.8
7.7
7.4
7.3
6.7
7.0
KVB 15900-524
84
-------
00
in
10
8
O
n
0 Two Strokes
O °ne Stroke
°0°*
o
o
•o
o
8
10
12
14
16
BOILER OUTLET P ARTICULATE LOADING, lb/10 BTU
18
20
Figure 5-27. Modified smoke spot number vs. particulate loading at the boiler outlet - Test
Site B.
KVB 15900-524
-------
10
8
O
' 6
CO
8
H
S 2
TWO Strokes
One Stroke
O
- .-, o o g
O O
O
O O
00 O
o o
o o
. f I
I I I I
2' 3 4 5 6 78 9 10
BOILER OUTLET COMBUSTIBLE LOADING, lb/10 BTU
Figure 5-28. Modified smoke spot number vs combustible loading at the boiler outlet - Test
Site B,
KVB 15900-524
-------
5.8 SOURCE ASSESSMENT SAMPLING SYSTEM
Seven SASS tests were run at Test Site B. One test was run on each
of three main test coals. These tests were run under identical conditions
of boiler load, excess O2, overfire air, and fly ash reinjection. In addi-
tion, two sets of SASS tests were run simultaneously at the boiler outlet
and the ESP outlet. These four tests, run on reload coal, were part of a
joint test venture with the Aerotherm Division of Acurex Corporation under
a separate EPA contract. The conditions under which the seven SASS tests
were run are shown in Table 5-8.
TABLE 5-8. SASS TESTS BUN AT SITE B
Test
No.
ISA
15B
16A
16B
30
31
33
Sample
Location
Boiler outlet
ESP outlet
Boiler outlet
ESP outlet '
Boiler outlet
Boiler outlet
Boiler outlet
Coal
Origin
Reload
Reload
Reload
Reload
Hatfield
Kentucky C.
Southeast
Load
87
87
89
89
78
77
79
Excess 02
4.3
4.3
7.0
7.0
6.0
6.0
6.1
OFA
"H2O
27
27
32
32
28
25
25
Contractor
for Analysis
Aerotherm
Aerotherm
Aerotherm
Aerotherm
Battelle
Battelle
Battelle
All SASS test results will be reported under separate cover at the
conclusion of this test program. The SASS sample catches will be analyzed
by combined gas chromatography/mass spectroscopy for total polynuclear con-
tent. In addition, seven specific polynuclear aromatic hydrocarbons (PAH) will
be sought. These are given in Table 5-9.
KVB 15900-524
87
-------
TABLE 5-9. POLYNUCLEAR AROMATIC HYDROCARBONS
ANALYZED IN SITE B SASS SAMPLES
Element Naae
7,12 Diaethylbenz (a) anthracene
Dibenz (a,h) anthracene
Benzo (c) phenanthrene
3-methyl cholanthrene
Benzo (a) pyrene
Dibenzo (a,h) pyrene
Dibenzo (a,i) pyrene
Dibenzo (c,g) carbazole
Molecular
Height
256
278
228
268
252
302
302
267
Molecular
Formula
C20H16
C22H14
C18H12
C21H16
C20H12
C24H14
C24H14
C2(W
Tables 5-10 through 5-19 summarize the test data obtained at
Test Site B. These tables, in conjunction with Table 2-1 in the Executive
Summary, are included for reference purposes.
KVB 15900-524
88
-------
TABLE 5-10. PARTICULATE EMISSIONS SUMMARY
TEST SITE B
a
3
o
at
a
M
Test
No.
2
3
4
6
7
8
9
11
12
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Coal*
K
H
K
S
s
K
K
R
R
R
R
R
S
K
K
H
H
K
S
K
H
K
K
Load
%
28
27
47
75
76
75
73
48
49
87
89
88
74
75
73
73
72
99
99
100
99
79
81
°2
%
11.3
10.9
8.0
5.2
4.4
10.2
6.9
8.8
8.0
4.3
7.0
6.6
6.5
4.7
6.8
6.8
6.3
5.5
5.1
5.3
5.3
6.4
6.5
EMISSIONS
lb/10°BTO
6.57
8.88
9.65
11.65
10.28
15.51
8.16
7.21
9.57
12.53
14.63
10.66
12.76
10.53
10.81
9.25
12.27
9.59
13.88
15.75
12.67
11.75
9.98
gr/SCF
2.16
3.53
4.26
6.25
5.79
5.67
3.90
2.98
4.22
7.10
6.94
5.20
6.28
5.82
5.20
4.45
6.11
5.04
7.49
8.39
6.75
5.82
4.91
Ib/hr
572
783
1374
2461
2635
3274
1787
1006
1417
3129
3652
2582
2843
2197
2191
1907
2558
2711
3874
4608
3616
2502
2219
Velocity
ft/sec
16.37
16.51
19.71
27.23
25.97
31.95
25.71
22.25
18.96
27.30
37.52
34.72
28.05
26.13
28.16
29.14
26.77
39.80
34.35
37.61
36.26
29.64
30.95
(-.
a
g
w
8
K
§
8
W
g
u
M
5
5
s
3
4
6
7
8
9
11
12
17
18
19
20
21
22
23
24
25
26
27
28
H
K
S
S
K
K
R
R
R
S
K
K
H
H
K
S
K
H
K
K
27
47
75
J6
75
73
48
49
88
74
75
73
73
72
99
99
100
99
79
81
10.9
8.0
5.2
4.4
10.2
6.9
8.8
8.0
6.6
6.5
4.7
6.8
6.8
6.3
5.5
5.1
5.3
5.3
6.4
6.5
0.543
0.446
0.469
0.755
0.830
0.518
0.481
0.500
0.467
0.810
0.563
0.561
0.619
0.824
0.485
3.530
0.596
0.635
0.591
0.343
0.193
0.199
0.265
0.423
0.326
0.263
0.189
0.205
0.244
0.398
0.311
0.270
0.298
0.411
0.235
1,910
0.317
0.338
0.293
0.169
48
63
99
194
175
113
67
74
113
180
117
114
128
172
137
985
174
181
126
76
20.04
24.39
32.11
31.70
39.23
32.11
2S.11
24.62
41.02
31.81
30.28
33.82
34.06
31.93
44.29
42.56
43.72
38.60
36.12
35.60
a. H
-------
TABLE 5-11. SUMMARY OF HEAT LOSSES AND EFFICIENCIES,
TEST SITE B
•i!
G u
U Q
IH §
U 2
i
=|
u
*
i
to
4
8
9
19
20
23
25
27
28
Q
8.88
12.00
8.32
7.93
8.26
7.96
7.66
8.05
7.68
MOISTURE
IN FUEL
0.14
0.40
0.45
0.32
0.46
0.52
0.27
0.48
0.54
1 (N
1*
H20 FROM
BUSTION I
4.26
4.11
4.23
4.20
4.41
4.42
4.21
4.28
4.24
X
z *^
M r^
O
to g
COMBUSTI]
MECHCOLI
3.76
3.04
2.85
5.38
6.53
8.09
6.76
4.41
4.84
to
m eg
COMBUSTI]
IN FLY3
0.19
0.19
0.17
0.28
0.27
0.24
0.24
0.30
0.16
z
H
CO 3!
to
COMBUSTI]
BOTTOM
1.21
0.64
1.07
0.54
0.45
1.01
0.64
0.04
0.80
CO
a
0)
M U
EH CO
CO D
O w
m M
8 Z
H
1
EH
5.16
3.87
4.09
6.20
7.25
7.48
7.64
4.75
5.80
S
Q
K
Pi
-------
TABLE 5-12. SUMMARY OF PERCENT COMBUSTIBLES IN REFUSE,
TEST SITE B
2
o
p
2
w
a
u
><
D
Z
B
Test
Number
2
4
8
9
19
20
23
25
27
28
31
AVERAGE
Boiler
Outlet
59.2
55.2
59.7
61.6
62.0
65.1
60.9
47.0
57.3
70.3
—
59.8
Mechanical
Collector
Outlet
—
15.4
21.9
28.8
28.0
26.7
25.0
28.3
29.2
—
25.4
Mechanical
Collector
63.0
50.9
31.6
55.3
62.9
76.6
79.5
56.7
47.2
60.2
76.1
60.0
Bottom
8.2
19.1
24.2
24.2
10.0
6.5
14.2
9.9
6.4
23.4
13.6
14.5
3
8
3
pa
^
3
21
22
26
30
AVERAGE
43.4
55.2
53.3
57.1
—
52.3
25.2
28.9
26.6
—
26.9
48.6
52.9
73.9
47.7
54.2
55.5
5.4
6.7
25.8
17.6
16.5
14.4
3
8
H
OT
if
fs
w
£C
P
W
6
7
18
24
33
AVERAGE
59.8
67.6
64.2
55.3
__
61.7
51.8
22.3
22.4
53.1
__
37.4
68.0
65.9
65.2
62.0
74.8
67.2
9.7
—
8.9
13.6
8.7
10.2
u
o
II
o *?
u w
a
11
12
15
16
17
AVERAGE
64.0
62.6
69.0
74.9
62.8
66.7
33.7
23.0
—
23.6
26.8
53.9
53.9
— —
66.0
57.9
4.0
4.0
__
5.7
4.6
KVB 15900-524
91
-------
TABLE 5-13.
COAL SIZING SUMMARY, TEST SITE B
»J
3
u
Q
jj
W
§
D
O
><
8
3
H
2!
§
Test
Number
1*
2*
4
8
9
19
20
23
25
27
28
31
AVERAGE
1"
93
93
92
94
94
94
95
95
95
97
97
93
95
PERCENT
1/2"
56
66
63
44
52
57
63
68
52
46
52
59
56
PASSING STATED
1/4"
23
26
30
21
28
25
28
36
25
20
23
31
27
SCREEN SIZE
#8
6
6
14
14
14
12
12
17
11
10
12
14
13
#16
0
0
9
11
9
9
7
11
8
7
8
9
9
5*
8
Q
.J
a
8
2
3
5
21
22
26
30
AVERAGE
97
96
87
95
97
97
95
72
73
47
67
73
58
65
42
39
21
36
41
29
34
15
18
10
17
20
15
16
5
11
7
11
12
10
9
W
J3 «c
H 8
8
CO
6
7
24
33
AVERAGE
•94
97
96
96
96
46
62
55
57
55
23
32
26
26
27
12
14
13
12
13
8
9
9
8
8
£ ^
g g
fe §
rt />
u w
a
11
12
15
16
17
AVERAGE
97
95
94
95
90
94
44
52
55
63
27
48
19
27
29
35
12
24
9
14
15
21
6
13
6
9
11
11
4
8
*Test No. 1 & 2 - Coal was not dried before screening. These two
not included in average.
KVB 15900-524
92
-------
TABLE 5-14.
FUEL ANALYSIS SUMMARY, KENTUCKY CUMBERLAND COAL,
TEST SITE B
to
u>
TEST NO. 1
PROXIMATE (as rec.)
« Holatur« 2.99
% Ash 7.58
% Volatile 34.62
% Fixed Carbon 54.61
BTO/lb 13426
% Sulfur 0.80
ULTIMATE (as rec.)
Moisture
Carbon
Hydrogen
Nitrogen
Chlorine
Sulfur
Ash
Oxygen (diff.)
ASH FUSION (reducing)
Initial Detonation
Soft. (H"tO
Soft. (H-1/2W)
Fluid
2489
3.45 1.60 4.39 5.05
7.15 8.85 8.83 5.92
34.94 34.92 33.97 34.90
54.46 54.63 52.81 54.13
13367 13485 13111 13434
0.91 0.84 1.05 0.93
4.39
72.66
4.96
0.85
0.15
1.05
8.83
7.11
2320
2570
2620
2700+
19 20 23 25 27
4.75 4.95 5.56 2.90 5.30
8.00 8.22 7.60 10.66 5.83
32.53 33.81 33.31 35.38 33.97
54.72 53.02 53.53 51.06 54.90
13115 12972 13077 12923 13266
0.87 1.06 0.91 0.91 0.68
2.90
72.27
4.98
1.19
0.07
0.91
10.66
7.02
2450
2660
2700+
2700+
28 31
5.98 4.36
5.81 8.18
33.88 34.43
54.33 53.03
13318 13150
0.87 0.93
4.36
73.29
4.81
1.10
0.07
0.93
8.18
7.26
2700+
2700+
2700+
2700+
AVG
4.27
7.72
34.24
53.77
13220
0.90
3.88
72.74
4.92
1.05
0.10
0.96
9.22
7.13
2490
2643
2673
2700
STD .
DBV
1.29
1.43
0.82
1.13
188
0.10
0.8S
0.51
0.09
0.18
0.05
0.08
1.29
0.12
193
67
46
0
KVB 15900-524
-------
TABLE 5-15.
FUEL ANALYSIS SUMMARY, HATFIELD COAL, TEST SITE B
TEST NO.
PROXIMATE (as rec.)
% Moisture
% Ash
% Volatile
% Fixed Carbon
BTU/LB
% Sulfur
ULTIMATE (as rec.)
% Moisture
% Carbon
% Hydrogen
% Nitrogen
% Chlorine
% Sulfur
% Ash
% Oxygen (diff.)
ASH FUSION (reducing)
Initial Deformation
Soft. (H=W)
Soft. (H=1/2W)
Fluid
3 5 21
1.90 1.66 4.81
ll.'3"8 "8.78 8.42
34.44 34.22 33.42
52.28 55.34 53.35
12960 13472 13097
0.98 0.89 0.89
1.90
72.15
4.97
1.48
0.08
0.98
11.38
7.06
2400
2700+
27QO+
2700+
22 26 30 32
5.89 3.25 4. 7J, . 5.31
8.26 8.53 8.35 7.79
33.05 34.35 32.73 33.35
52.80 53.87 54.21 53.55
12926 13235 13222 13049
0.91 0.95 0.87 0.99
4.71
73.61
4.79
1.38
0.11
0.87
8.35
6.18
2700+
2700+
2700+
2700+
STD
AVG DEV
3.93 .. 1.68
8.79 1.18
33.65 O. 68
53.63 0.99
13137 1 189
0.93 0.05
i
3.31 J..99
72.88 1.03
4.88 0.13
1.43 0.07
0.10 0.02
0.93 0.08
9.87 2.14
6.62 0.62
2550 ' 212
2700+ ; 0
2700+ -: 0
2700+ 0
KVB 15900-524
-------
TABLE 5-16.
FUEL ANALYSIS SUMMARY, SOUTHEAST COAL, TEST SITE B
ui
TEST NO.
*r ~ •
PROXIMATE (as rec.)'
% Moisture
% Ash
% Volatile
% Fixed Carbon
BTU/LB
% Sulfur
ULTIMATE (as rec.)
Moisture
Carbon ,
Hydrogen
Nitrogen
Chlorine
Sulfur
% Ash
% Oxygen (diff.)
ASH FUSION (reducing)
Initial Deformation
Soft. (H«W)
Soft. (H*4/2W) '
Fluid
6 7 18
1.99 1.08 3.64
9.41 6.48 5.66
33.95 35.60 35.24
54.65 56.84 55.46
13011 13981 13696
0.83 0.82 0.71
1.08
78.08
5.25
1.37
0.13
0.82
6.48
6.79
2700+
2700+
2700+
2700+
24 33
5.03 2.75
16.79 6.77
30.97 35.17
47.21 55.31
11667 13649
0.75 0.79
5.03 2.75
65.56 76.37
4.44 5.06
1.30 1.11
0.10 0.15
0.75 0.79
16.79 6.77
6.03 7.00
2520 2600
2700+ 2700+
2700+ 2700+
2700+ 2700+
STD
AVG DEV
2.90 1.52
9.02 4.56
34.19 1.90
53.89 3.82
i
13201 928
0.78 0.05
2.95 1.98
73.34 6.79
4.92 0.42
1.26 0.13
0.13 0.03
0.79 0.04
10.01 5.87
6.61 0.51
2607 90
2700+ 0
2700+ 0
2700+ 0
KVB 15900-524
-------
TABLE 5-17.
FUEL ANALYSIS "SUMMARY, COAL FROM DEAD STORAGE, TEST SITE B
I
1
TEST NO.
PROXIMATE (as rec.)
% Moisture
% Ash
% Volatile
% Fixed Carbon
BTU/LB
% Sulfur
ULTIMATE (as rec.)
' Moisture
Carbon
Hydrogen-
Nitrogen
Chlorine
Sulfur «•
Ash
Oxygen (diff.)
ASH FUSION (reducing)
Initial .Deformation
Soft. (H-W)
Soft. (H-1/2W)
Fluid
11 12 15 16 17
;
1'.99 4.76 5.48 6.46 3.20
5.08 6.50 6.47 6.96 6.99
35.44 34.88 34.21 33.73 35.28
57.49 53.86 53.84 52.85 54.53
I ^
14077 13368 13181 13001 13535
0.75 0.85 0.71 0.75 0.77-
^
5.48 6.46
74.11 72.78
' ,, 4.99 4.88
1.44 1.45
0.12 0.11
0.71 0.75
6.47 6.96
6.68 6.61
*
, 2700+ 2700+
\ 2700+ 2700+
'"'' 2700+ 2700+
2700+ 2700+
STD
AVG DEV
4.38 1.79
6.40 0.78
34.71 0.72
54.51 1.77
13432 412
0.77 0.05
5.97 0.69
73.45 0.94
4.94 0.08
1.45 0.01
0.12 0.01
0.73 0.03
6.72 0.35
6.65 • 0.05
2700+ 0
2700+ 0
2700+ " 0
2700+ 0
KVB 15900-524
-------
TABLE 5-18
• "• '- ': ' ' 'M'.J'.
', QF MIJBERAL ANALYSIS OF COAL ASH
TEST SITE B
Test No.
Silica, Si02
Alumina,
Titania.
Ferric Oxide, FC2O3
Lime, Cao
Magnesia, MgO
Potassium Oxide, K2o
Sodium Oxide, Na2O
Sulfur Trioxide, S03
Phos Pentoxide,'
Unde tenni ne d
Alk as Na20
Silica Value
Base/Acid
% Pyritic Sulfur
% Sulfate Sulfur
t Organic Sulfur
Kentucky
Cumberland
i
1 8
54.44
26.78
0.99
9.29
2.02
1.43
2.50
0.52
1.42
0.23
0.38
100.0
0.20
81.04
0.19
2755
—
25
54.90
27.14
1.10
7.22
2.80
1.32
1.95
0.52
1.71
0.17
1.17
100.0
0.20
82.88
0.17
2810
—
31 1
52.64
31.40
1.54
6.44
1.90
1.05
2.30
0.63
1.05
0.44
0.61
100.0
—
84.86
0.14
2870
0.20
0.00
0.73
Hatfield
i
1 3
53.99
27,85
1.21
8.26
1.85
1.32
2.20
0.42
1.18
0.40
1.32
100.0
0.22
82.53
0.17
2800
--
30 1
55.65
29.30
1.76
6.34
1.40
0.87
2.15
0.77
0.86
0.38
0.52
100.0
—
86.60
0.13
2900+
0.18
0.03
0.66
Southeast
i
1 7
53.39
30.71
1.54
6.41
1.90
0.75
1.15
0.62
1.13
0.50
1.90
100.0
0.09
85.49
0.13
2900+
—
24
54.90
28.56
1.21
7.74
1.95
1.08
1.95
0.42
1.17
0.23
0.79
100.0
0.30
83.60
0.16
2830
—
33 1
54.14
29.99
1.65
6.60
2.00
0.68
1.23
0.47
1.15
0.62
1.47
100.0
—
85.37
0.13
2900+
0.17
0.02
0.60
Reload from
Long Term
Storage
i
1 15
54.14
30.00
1.43
6.35
1.90
0.81
1.55
0.47
1.43
0.28
1.64
100.0
0.10
85.66
0.13
2900+
—
16 1
53.39
30.71
1.32
7.22
1.97
0.90
1.85
0.42
1.43
0.31
0.48
100.0
0.12
81.20
0.14
2850
—
KVB 15900-524
97
-------
TABLE 5-19. SUMMQr OF STEAM F&CNS AND HEAT RELEASE RATES,
TEST SITE B
Steam Front Foot Grate Furnace
Test Capacity Flo* Beat Input Beat Output Beat Release Beat Release Heat Release
10*BTO/hr 10*PTO/hr lo4BTO/ft/hr IjfoTO/ftfor 10*BTU/ftyhr
•w*
1
2
3
4
S
6
7
8
9
10«
11
12
13*
14*
IS
1ft
17
18
19
20
21
22
23
24
25
26
27
28
30
31
32
33
41.1
27.7
27.2
47.3
46.7
75.5
75.8
74.5
72.5
31.3
47.6
48.7
71.6
95.7
87.4
88.7
88.3
73.7
75.1
72.8
72.8
71.8
98.9
98.8
100.2
99.0
79.4
80.9
78.1
77.0
78.0
78.8
»V •!• ^ ••»
82.1
55.3
54.3
94.fi
93.3
151.0
151.7
149.0
145.0
62. S
95.2
97.4
143.2
191.5
174.8
177.4
176.7
147.3
150.2
145.6
145.7
143.6
197.9
197.5
200.4
198.0
158.8
161.7
156.3
153.9
156.0
157.6
123.6
87.1
88.1
142.4
138.8
211.2
256.4
211.1
219.0
95.1
139.5
148.1
205.9
280.3
249,1
249.6
242.2
209.1
208.6
202.7
206.1
208. S
282.7
279.1
292. «
285.4
212.9
222.4
222.7
215.1
211.9
226.2
88.8
59.8
58.3
102.3
100.8
163.2
163.5
159.9
156.8
67.5
102.8
105.1
156.0
209.5
189.6
193.0
193.7
159.2
162.8
158.4
159.4
155.7
216.8
215.4
218.5
215.8
171.7
174.6
169.3
166.8
169.0
170.8
616.9
434.9
440.0
710.7
692.9
1054.4
1279.8
1053.8
1093.2
474.9
696.4
739.2
1027.8
1399.5
1246.6
1246.1
1209.0
1043.8
1041.5
1012.1
1029.1
1040.9
1411.3
1393.4
1460.fi
1424.7
1063.1
1110.1
1111.7
1073.9
1057.6
1129.1 •
334.0
235.4
238.2
384.8
375.1
570.8
692.9
570.5
591.8
257.1
377.0
400.2
556.4
757.6
674.9
674.6
654.5
565.1
563.8
547.9
557.1
563.S
764.1
754.4
790.7
771. 3
575.5
601.0
601.9
581.4
572.6
611.3
95.7
67.5
68.3
110.3
107.5
163.6
198.6.
163.5
169.6
73.7
108.1
114.7
159.5
217.1
193. 4
193.4
187.6
162.0
161.6
157.0
1S9.7
161.5
219.0
216.2
226.6
221.1
164.9
172.2
172.6
166.6
164,1
175.2
* An average BTU/lb was used, for Test 10 - 13,089
for Tests 13 fi 14 - 13,432
KVB 15900-524
98
-------
APPENDIX A. OVERFIRE AIR FLOW TRAVERSE DATA »• TEST SITE B
Pressure Reading With an S Type Pitot Tube
Reading in Inches of Hater Column
Area of Duct =4.20 ft
Velocity Point
Vertical
1
2
3
4
5
6
7
8
9
10
11
12
Maximum
Overfire Air
C34" HO)
AP, in. H0
0.60
0.75
0.85
0.85
0.80
0,75
0.65
0.65
0.75
0.85
0.85
0.70
Minimum
Overfire Air
(6.5" HO)
&P, inf HO
0.40
0.45
0.40
0.40
0.45
0.40
0.40
0.45
0.45
0.40
0.40
0.35
Horizontal
1
2
3
4
5
6
7
8
9
10
11
12
AVERAGE
0.75
0.80
0.80
0.85
0.85
0.75
0.65
0.65
0.65
0.70
0.65
0.50
0.7354
0.40
0.40
0.50
0.40
0.40
0.40
0.40
0.40
0.45
0.45
0.40
0.35
0-.4125
KVB 15900-524
99
-------
APPENDIX B. OVERFIRE AIR FLOW CALCULATION - TEST SITE B
Maximum Overfire Air {34" H20)
Average AP = 0.7354 in. HjjO
Ts = 82° F
Ps = 33.46 in. Hg
Ps = 0.86
Gs = 1.00
As = 4.20 ft2
V = 174 Ps./ APtTs
/
"
GS
CO.
\JIO.
407
(455J
i.oo
1.00
2826 ft/aiin
47.09 ft/sec
SCFM = V AS
Ps
407
n
= (2826) (A
= 12,973 SCFM
PV
RT
CO. 7301. C5 301
= 33.53 moles /min
= 972.4 Ib/min
= 58,344 Ib/hr
Minimum Overfire Air C6T5" H?0)
Average AP = 0.4125 in. H20
Ts = 82° F
Ps = 33.31 in. Hg
Fs = 0.86
Gs = 1.00
As = 4.20 ft2
C174)CO.86)
\/CO.
4125)(542)
407
453
1.00
1.00
= 2121 ft/ndn
- 35.35 ft/sec
SCFM - (2121)(4.20)
= 9,695 SCFM
530
542
n =
(1)(9,695)
(0.730)(530)
=• 25.06 moles/kin
- 726.7 U>/min
= 43,600 Ib/hr
KVB 15900-524
100
-------
Test
No.
1
Load
7.
41
15 Blr 87
15 ESP "
16 Blr 89
16 ESP "
30 Blr 78
°2
7.
Coal+
9.9 K
4.3 R
I
7.0 R
r
t
6.0 H
30 ESP '
31 Blr 77
6.0 K
31 ESP '
32 Blr 78
33 Blr 79
II
5.9 H
6.1 S
SULFUR IN FUEL
'uel Sulfur
7.
0.80
0.71
11
0.75
II
0.87
t
0.93
It
0.99
0.79
As S02
lb/106BTU
1.192
1.077-
*i
1.154
1.316
1.414
••
1.517
1.158
SULFUR IN BOTTOM ASH*
Ash Sulfur
7.
__
—
•
.
0.08
0.03
0.04
0.03
As S02
lb/106BTU
__
--
--
.0048
.0017
.0022
.0013
Retention
7.
--
—
0.37
0.12
0.15
0.11
Average retention 0.197.
SULFUR IN FLY
Ash Sulfur
7.
__
--
--
0.07
0.07
0.08
0.08
As S02
lb/106BTl
__
--
--
.0116
.0219
.0129
.0189
ASH**
Retentior
7.
-_
--
--
0.88
1.55
0.85
1.63
Average retention 1 . 237.
SULFUR EMISSIONS
sox
ppm(dry)
545
392
150
469
273
472
367
428
391
446
397
S0xas S02
lb/106BTU
1.055
0.755
0.289
..• 0.903
0.525
0.922
0.717
0.828
0.757 -
0.871
0.776
Fuel Sulfur
Emitted, 7.
897.
71?.
277.
787.
467.
707.
547.
597.
547.
577.
677.
K - Kentucky Cumberland Coal
H - Hatfield Coal
S - Southeast Coal
R - Relead coal from dead storage
* Based on 407. of coal ash as bottom ash
** Based on 601 of coal ash as fly ash
Note: The sulfur oxide sample probe used at test site B may have been defective resulting in lower measured sulfur oxide
concentrations than actually existed. Because of this possibility, the site B SO data is presented here in the
appendix rather than in the main body of the report.
APPENDIX C. SULFUR BALANCE SUMMARY - TEST SITE B
KVB 15900-524
-------
APPENDIX D
ENGLISH AND METRIC UNITS TO SI UNITS
To Convert
in
in
ft
To
cm
cm2
m
ft3
Multiply By
2.540
6.452
0.3048
0.09290
0.02832
Ib
Ib/hr
lb/106BTU
g/Mcal
BTU
BTU/UJ
BTU/hr
J/sec
J/hr
BTU/ft/hr
BTU/ft/hr
BTU/ft2/hr
BTU/ft2/hr
BTD/ft3/hr
BTO/ft3/hr
psia
"H20
Rank in e
Fahrenheit
Celsius
RanJcine
Kg
Mg/s
ng/J
ng/J
w
w
w
W/m
J/hr/m
W/m2
J/hr/m2
W/m3
J/hr/m3
Pa
Pa
Celsius
Celsius
Kelvin
Kelvin
0.4536
0.1260 .
430
239
1054
0.002324
0.2929
1.000
3600
0.9609
3459
3.152
11349
10.34
37234
6895
249.1
C - 5/9R-273
C - 5/9(F-32)
K = C+273
K - 5/9R
COAL FUEL ONLY
ppm @ 3% O2 (SO2)
ppm @ 3% 02 (SO3)
ppm § 3% O2 (NO)
ppm @ 3% O2 (NO2)
ppm i 3% O2 CCO)
ppm § 3% 02 (CH4)
ng/j
ng/J
ng/J
ng/J
ng/J
ng/J
0.851
1.063
0.399
0.611
0.372
0.213
102
KVB 15900-524
-------
APPENDIX E
SI UNITS TO ENGLISH AND METRIC UNITS
To Convert From
cm
cm2
in
m2
Kg
Mg/s
ng/J
ng/J
J
JA9
J/hr/m
J/hr/m2
J/hr/m3
W
W
W/m .
W/m2
K/m3
Pa
Pa
Kelvin
Celsius
Fahrenheit
Kelvin
TO
in
in2
' ft
ft2
ft3
Ib
lb/hr
Ub/106BTU
g/Mcal
BTU
BTU/lb
BTU/ft/hr
BTU/ft2/hr
BTU/ft3/hr
BTU/hr
J/hr
BTU/ft/hr
BTU/ft2/hr
BTU/ft3/hr
psia
"H20
Fahrenheit
Fahrenheit
Rankine
Rankine
Multiply By
0
0
3
.3937
.1550
.281
10 . 764
35.315
2.205
7.937
0.00233
0.00418
0.000948
4.303
0,000289
0.0000881
0.0000269
3.414
0.000278
1.041
0.317
0.0967
0.000145
0.004014
F
F
R
R
1.8K-460
1.8C+32
F+46O
1.8K
COAL FUEL ONLY
ng/J
ng/J
ng/J
ng/J
ng/J
ng/J
ppm
ppm
ppm
ppm
ppro
ppm
@
§
e
3%
3%
3%
3%
3%
3%
02
°2
°2
°2
°2
°2
(S02)
(S03)
(NO)
(N02)
(CO)
(CH4)
1.18
0.941
2.51
1.64
2.69
4.69
103
KVB 15900-52*
-------
APPENDIX P
SI PREFIXES
Multiplication Factor Prefix SI Sygfeol
1012 tera T
109 giga G
106 mega M
103 kilo k
102 hecto* h
101 deka* da
10-x deci* d
10-2 centi* c
10-3 milli n
10~6 micro y
10"^ nano n
10"12 pico p
10~15 femto f
10"18 atto a
*Not recommended but occasionally used
104 KVB 15900-524
-------
APPENDIX G
EMISSIONS UNITS CONVERSION FACTORS
FOR TYPICAL COAL FUEL (HV - 13,320 BTU/LB)
NOTE: I. Values in parenthesis can be used for all flue gas constituents such as oxides of carbon,
oxides of nitrogen, oxides of sulfur, hydrocarbons, participates, etc.
2. Standard reference temperature of 530°R was used.
KVB 15900-524
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse tie fore completing)
1. REPORT NO.
EPA-600/7-79-041a
3. RECIPIENT'S ACCESSION NO.
Field Teste of industrial Stoker Coal-
fired Boilers for Emissions Control and Efficiency
Improvement—Site B
5. REPORT DATE
February 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
J. E.Gabriels on, P.L.Langsjoen, and T.C.Kosvic
I. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
KVB, Inc.
6176 Olson Memorial Highway
Minneapolis, Minnesota 55422
10. PROGRAM ELEMENT NO.
EHE624
11. CONTRACT/GRANT NO.
EPA-IAG-D7-E681 and
DOE -EF-77-C-01-2609
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development *
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PEI
Final; 12/77 - 3/78
PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/600A3 and DoE
IB. SUPPLEMENTARY NOTESIERL-RTP protect officer is R.E. Hall. (*) Cosponsors are DoE
(W.T.Harvey, Jr.) and the American Boiler Manufacturers Association. EPA-600/
7-78-136a is a similar Site A report.
. ABSTRACT
gives results of field measurements made on a 200,000 Ib/hr
spreader stoker boiler. The effect of various parameters on boiler emissions and
efficiency was studied. Parameters studied included overfire air, flyash reinjection,
excess air, boiler load, and fuel properties. Measurements included gaseous emis-
sions, particulate emissions, particle size distribution of the flyash, and combus-
tible content of the ash. Gaseous emissions measured were O2, CO2, CO, NO, SO2,
and SO3 in the flue gas. Sample locations included the boiler outlet, multiclone out-
let, and electrostatic precipitator outlet. In addition to test results and observations,
the report describes the facility tested, coals fired, test equipment, and procedures.
Increasing the overfire air flow was found to reduce particulate emissions by 25%.
Overfire air flow did not significantly affect NO emissions. A 30% reduction in fly-
ash reinjection reduced particulate loading at the boiler outlet 40%, and reduced
boiler efficiency 1.3%. At design capacity, the boiler emitted between 12.7 and 15.8
Ib/million Btu particulate matter and 225-315 ppm NO at the boiler outlet.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Air Pollution
Boilers
Combustion
Coal
Field Tests
Dust
Stokers
Improvement
Efficiency
Flue Gases
Fly Ash
Particle Size
Nitrogen Oxides
Sulfur Oxides
Air Pollution Control
Stationary Sources
Combustion Modification
Spreader Stokers
Particulate
Overfire Air
Flyash Reinjection
13B
13A
21B
21D
14B
11G
07B
8. DISTRIBUTION STATEMENT
Unlimited
IB. SECURITY CLASS (TMtReport)
Unclassified
21. NO. OF PAGES
113
20. SECURITY CLASS (Thiipfge)
Unclassified
22. PRICE
EPA Form 2210-1 |«-73|
106
------- |