United States
Environmental Pri>tt>c11< >n
Agency
Industrial Environmental Research
laboratoi v
Research Tr,,in>ilt> p,,ik Ni: .;7711
EPA 600 7 78-214
November 1978
Performance and
Economic Evaluation of a
Hot-side Electrostatic
Precipitator
Interagency
Energy/Environment
R&D Program Report
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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.
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EPA-600/7-78-214
November 1978
Performance and Economic
by
G.H. Merchant Jr. and J.P. Gooch
Southern Research Institute
2000 Ninth Avenue, South
Birmingham, Alabama 35205
Contract No. 68-02-2185
Program Element No. EHE624
EPA Project Officer: Leslie E. Sparks
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
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ABSTRACT
The report gives results of measurements—to determine the
overall mass and fractional collection efficiency of a hot-side
electrostatic precipitator (ESP)—across 1 chamber of a
16-chambered ESP. Measurements of fractional efficiency were
conducted across the entire ESP. In situ and laboratory
resistivity measurements were performed, and voltage-current
characteristics of the power supplies were obtained. An
engineering analysis was conducted, including an estimate of
the specific collecting area required for a cold-side ESP on the
same boiler. Results include: (1) voltage waveforms and
secondary voltage-current relationships showed characteristics
similar to back-corona although fly ash resistivity was 5 x 10
to the 9th power ohm-cm at 350°C (in situ determination); (2) ESP
operation was sensitive to resistivity variation in a resistivity
region (2 x 10 to the 10th power to 8 x 10 to the 8th power
ohm-cm from laboratory determinations) where no sensitivity was
expected; (3) overall mass collection efficiency of an isolated
chamber was 99.22% for a specific collection area of 52.6 sq m/
(cu m/sec), average secondary voltage was 22 kV, and average
secondary current density was 40 nA/sq cm; and (4) the turnkey
cost of the ESP system was estimated at $34,940,000 ($44/kW) in
1977 dollars.
11
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CONTENTS
Abstract ii
Figures iv
Tables vii
Acknowledgments ix
Sections
1 Introduction 1
Objective 1
Scope of Work . 1
2 Conclusions 2
3 Precipitator Evaluation 5
Hot-Side Precipitator Survey and
Site Selection 5
Description of Facility 5
Test Program 14
Measurement Techniques 15
Test Results 20
Theoretical Analysis 76
4 Engineering Analysis 91
Capital and Operating Costs of Existing Unit... 91
Operating and Maintenance Problems 99
Description and Estimated Costs of an
Improved Precipitator 103
References 107
Appendices
1 Description of Methods 110
2 Impactor Substrate Weight Changes for Blank Runs.... 147
3 Voltage-Current Data 150
4 Size-Dependent Elemental Concentration Data 180
iii
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FIGURES
Number Page
1 Ductwork and precipitator arrangement for
Navajo Station, Unit 3 .,10
2 Precipitator chamber arrangement 11
3 Rapper control arrangement 13
4a Chronological display of impactor and ultrafine
measurements 16
4b Chronological display of mass train measurements... 17
5 Differential size distributions, Chamber 8 inlet... 28
6 Average inlet differential size distribution 29
7 Average inlet cumulative size distribution 30
8 Outlet differential size distribution... 31
9 Fractional efficiency for Chamber 8 and total ESP.. 32
10 Average outlet cumulative size distribution, Total
ESP 34
11 Relative concentration of particles with and without
soot blowing, Chamber .8 Outlet ..'-.'. . 35
12 Relative concentration of :particles with and without
soot blowing, stack location 36
13 Relative concentration of 0.092 ym particles with and
without soot blowing, Chamber 8 Inlet 37
14 Differential number size distributions, Chamber 8 '-'-'•'
Inlet 38
15 Differential number size distributions, outlet
sampling locations ;.. . 39
16 Resistivity vs temperature, 7/15-16/77... ... 42
17 Resistivity vs temperature, 7/18-19/77- r. ...... 43
iv
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Figures
(Continued)
18 Resistivity vs temperature, 7/21-22/77 44
19 Resistivity vs temperature, 8/2-3/77 45
20 Resistivity vs temperature, Utah Coal 46
21 Voltage-current curves for chambers 7 and 8,
July 12-13, 1977 63
22 dM/dlogD vs particle diameter for all impactors
operated at the main inlet of the #3 precipitator
and cyclone run #7 65
23 dM/dlogD vs particle diameter for all impactors
operated at the inlet of chamber #8 and cyclone
run #3 66
24 dM/dlogD vs particle diameter for all impactors
operated at the outlet of chamber #8 and cyclone
run #5 67
25 Apparent elemental collection efficiency (chamber 8) 72
26 Particles/minute vs time for 6-12 ym particles,
February 1, 1977 74
27 Ultrafine and impactor fractional efficiencies for
rap-no rap test 75
28 Theoretical voltage current relationships for wire
diameter of 0.268 cm (0.1055 in), wire to plate
spacing of 11.45 cm (4.5 in), and wire to wire spacing
of 22.9 cm 78
29 Comparison of theoretical (be = 15 cm2/volt-sec) and
experimental (C field, ch. 7 & 8, July 15, 1977)
voltage-current curve 80
30 Theoretical and experimental voltage-current
relationships for various wire diameters 82
31 Voltage waveforms for C field, ch. 7 & 8 83
32 Voltage-current relationship for C fields, ch. 7 & 8
and ch. 5 & 6 84
33 Outlet field voltage-current curves for ch. 7 & 8
(Navajo) and another hot-side precipitator installa-
tion 86
v
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Figures ,
(Continued)
34 Measurements and model projections of collection
efficiency for hot-side operating parameters 87
35 Model projection for cold-side operating
parameters 90
VI
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TABLES
Number Page
Partial list of hot-side electrostatic precipitator
installations ,
2 Predicted performance of units 1, 2, and 3 of the
Navajo Generating Station 9
3 Mass concentrations obtained during Phase I with
mass trains and impactors 21
4 Average inlet and outlet parameters, chamber 8 22
5 Statistical analysis of effect of soot blowing on
mass emissions 22
6 Comparison of inlet mass train and impactor loadings. 24
7 Phase II, main inlet and stack impactor mass loadings 24
8 Phase II, main inlet and stack parameters 26
9 Average blank corrections for impactor components.... 26
10 In_ situ resistivity data 41
11 Chemical analysis of Utah coal ash used for Figure 20 48
12 Coal analyses, Phase 1 49
13 Coal analyses, Phase II 50
14 Ash analyses, Phase I and Phase II 51
15 Phase I gas analyses 53
16 Phase II gas analyses 55
17 Average electrical operating parameters, chambers
7 and 8, Phase I.. 59
18 Voltage-current curve data, chambers 7 and 8 61
19 Cyclone assembly operating parameters 64
20 Mass concentration and efficiency from cyclone
assembly (Phase I) 69
VII
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Tables
(Continued)
21 Concentration of elements listed in parts per
million by weight 70
22 Elemental penetration across chamber #8 71
23 Unit #3 precipitator cost 92
24 Operating and maintenance costs for Unit #3,
ash handling system 93
25 Operating and maintenance costs for Unit #3, normal
maintenance, repair, and operations 95
26 Operating and maintenance costs for Unit #3 ESP,
charges for testing, adjusting and/or modifications. 96
27 Estimated power cost of precipitator 97
28 Summary of operating costs 98
29 ESP chamber availability 102
30 Recommended design parameters for improved
performance 105
Vlll
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ACKNOWLEDGMENTS
The assistance of Dr. Leslie E. Sparks, Project Officer,
Environmental Protection Agency, is greatly appreciated. The
assistance and cooperation of Salt River Project personnel
during the test program and in compiling the required information
for the engineering analysis are also gratefully acknowledged.
The cooperation of the Electric Power Research Institute is also
greatly appreciated.
IX
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SECTION 1
INTRODUCTION
OBJECTIVE
This report describes the methods employed for and the
results obtained from an evaluation of the performance and
economics of a hot-side electrostatic precipitator installed on a
750 MW coal-fired utility boiler firing low-sulfur Western coal.
SCOPE OF WORK
The major tasks performed in accomplishing this evaluation
were as follows:
• A limited survey of utilities using hot-side electrostatic
precipitators, followed by the selection of a site for the
evaluation program. The Navajo Generating Station of the
Salt River Project in Page, Arizona, was selected.
• The preparation of a detailed test plan which described a
field test designed to determine the performance of the
precipitator.
• The performance of a two-phase test program which included
characterization of the performance of an individual
chamber of the dust collector (Phase I) and the perform-
ance of the entire precipitator (Phase II). The data
obtained included overall mass collection efficiency,
efficiency as a function of particle diameter, flue gas flow
rates and composition, coal and fly ash compositions,
precipitator electrical operating parameters, and dust
resistivity. A separate and earlier test program,
sponsored by EPRI and the Salt River Project, was
conducted to determine the collection efficiency losses
due to electrode rapping. Results from this program are
included for completeness.
9 An engineering analysis of the electrostatic precipitator
system. This portion of the program was conducted with
the assistance of Salt River Project and Bechtel Corpora-
tion personnel. The analysis included a projected design
for a cold-side precipitator installed on the same boiler.
The SoRI electrostatic precipitator mathematical model was
used in the analysis.
1
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SECTION 2
CONCLUSIONS
The following conclusions'have been obtained from this study:
(1) The overall mass collection efficiency of an isolated
chamber (Chamber 8) of the electrostatic precipitator
system was 99.22%. A minimum value of 92% was deter-
mined at 0.50 ym particle diameter in the efficiency
as a function of particle diameter relationship. These
results were obtained with an average secondary voltage
of 22 kV, an average secondary current density of 40
nA/cm2, a specific collection area of 52.6 m2/(m3/sec),
and a dust resistivity (in situ determination) of
approximately 5x109 ohm-cm at 350°C.
(2) The apparent collection efficiency of the entire pre-
cipitator, based on a limited Brink impactor traverse
of the main inlet and an Andersen impactor traverse of
the stack sampling location, was 98.56%. The stack
location measurements indicated a total particulate
mass emission rate of 30.8 ng/J (0.0716 lb/106 Btu)
of which 9.03 ng/J (0.021 lb/106 Btu) consisted of
particles with diameters less than 2.0 ym.
(3) Measured values of dust resistivity at 350°C (both
iri situ and laboratory) are in reasonable agreement
with those obtained from predictions based on ash
composition.
(4) Voltage waveforms and secondary voltage-current rela-
tionships obtained during the test period exhibited
certain characteristics similar to back corona from
highly resistive dust layers at 150°C. However, overall
and fractional efficiency data from the test measure-
ments are significantly larger than those obtained
from a theoretical model when the observed operating
parameters are used as input data. Thus, if a bi-
polar charging environment from back corona does exist,
the deleterious effects are partially compensated for
by a phenomena not represented in the model. It is
hypothesized that a significant portion of the corona
current is carried by free electrons, which results in
higher values of charge on the particles than those
predicted by the present charging model based on ionic
values of charge carrier mobility.
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(5) Attainable values of secondary voltage are signi-
ficantly lower than those observed with hot-side
precipitators collecting ash from Eastern coals at
approximately the same temperature. The low voltages
are hypothesized to result from a combination of high
effective mobilities for the charge carrying species
of the gas stream and an electrical discharge process
which occurs in the deposited dust layer and which per-
sists at voltages below the normal corona onset voltage.
The operating voltages and the V-I relationships were
found to be strongly dependent upon electrode cleanli-
ness, even though the measured values of dust resistiv-
ity were relatively low.
(6) The sensitivity of hot-side precipitator operation to
resistivity variation in a resistivity region (2x1010
to 8x108 ohm-cm) where no sensitivity was expected was
observed when load dropped from 800 to 400 MW and the
precipitator operating temperature dropped from 360°C
to 233°C. The TR set panel meters indicated heavy
sparking, and collection efficiency decreased even
though the specific collection area was approximately
doubled. The drop in collection efficiency could
undoubtedly have been avoided if the TR set control-
lers had maintained the operating points at low
sparking rates. The test results are important,
however, in that they indicate the factors which
must be considered if a hot-side precipitator is to
be used in a variable temperature operation. (These
results were obtained prior to the EPA-sponsored test
series.)
(7) The two principal causes of the lower than desired
performance of the unit are the relatively low oper-
ating voltages and the relatively low values of
specific collecting area. The recommended value of
specific collecting area to achieve the design collec-
tion efficiency of 99.5% is 93.9 m2/(m3/sec), based on
the results during the test period. An alternative
approach to the large increase in plate area, which
could not be quantified by the measurements performed
during this test series, is to determine the rela-
tionship between dust deposits, voltage-current
curves, and collection efficiency. Pilot-scale
experiments at the plant site are recommended to
determine if it is practical to consistently achieve
the "clean plate" values of performance which have
been observed.
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(8) The turnkey cost of the electrostatic precipitator
system, including the ash handling system, duct work,
and auxiliaries was estimated as $34,940,000, or $44/
kW in 1977 dollars.
(9) The annual operating costs for the electrostatic pre-
cipitator system from June 1976 to June 1977 were
$1,271,000, or 0.23 mills/kWh. If the amortized capital
costs are included (from 8 above), the operating costs
are 1.16 mills/kWh, based on 7000 hr/year.
(10) Although the precipitator has not operated reliably with
respect to design efficiency, it has been reliable from
a mechanical standpoint. The most significant mainten-
ance problems were air infiltration and ash buildup in
hoppers.
(11) The estimated cost of an improved precipitator system,
based on the plate area requirements indicated by per-
formance during the test period, is $60,440,000, or
$75.5/kW (1977 dollars). The estimated costs of cold-
side designs for 99.5% minimum collection efficiency
were 52.4 and 65.1 $/kW, based on fly ash resistivities
of 9x1010 and 7x1011 ohm-cm, respectively.
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SECTION 3
PRECIPITATOR EVALUATION
HOT-SIDE PRECIPITATOR SURVEY AND SITE SELECTION
Table 1 gives the results obtained from a limited survey of
utilities concerning the usage of hot-side precipitators for
collecting ash from low-sulfur coals. The Navajo Generating
Station is the largest existing hot-side precipitator installa-
tion and collects ash from a representative low sulfur, but not
necessarily low sodium, Western coal. The Navajo Station has
also experienced precipitator operating problems which are
generally typical of those encountered at other similar installa-
tions. It was selected as the test site for the following reasons
1. The management of the Project agreed to participate in
the evaluation program and to provide valuable assis-
tance in the performance of the field test and the
engineering analysis.
2. The management of the Project maintains an active task
force for the purpose of studying and solving the prob-
lems associated with the hot-side precipitator. There-
fore, the site offered the potential of providing use-
ful information concerning practical operating problems
associated with hot-side precipitator systems.
3. The existing sampling ports offered considerable flexi-
bility for the test program.
4. The design parameters of the precipitator system were
representative of the "state of the art" for hot-side
precipitators.
5. Southern Research Institute had performed additional
tests under EPRI and Salt River Project sponsorship
which would be useful in conducting the evaluation.
DESCRIPTION OF FACILITY
The Navajo Generating Station is located approximately four
miles east of Page, Arizona, on the Navajo Indian Reservation at
an elevation of 1330.45 m (4365 ft) and consists of three 750 MW
generating units. The test program was conducted on the precipi-
tator installed on Unit Three.
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TABLE 1
SURVEY OF UTILITIES OPERATING HOT-SIDE ELECTROSTATIC PRECIPITATORS AND BURNING LOW-SULFUR WESTERN COALS
Volume Flow
MW's KACFM Am3/mln
Design
Temperature
Op oc
SCA
ftz/KACFM m2/(m3/sec)
Efficiency
Test
Efficiency
Public Service Co. of Colorado - Comanche
350 2514 1187 828 442
# 1 - Research-Cottrell
296 58.3 99.59
330 2800 1322
Iowa Power and Light Co.
71 410 194
Iowa Power and Light Co.
116 620 293
Iowa Power and Light Co.
47 284 134
Iowa Power and Light Co.
90 421 199
700 371 398 78.3
- Des Moines #10 - UOP
645 341 246 48.4
- Des Moines #11 - UOP
635 335 244 48.0
- Council Bluffs #1 - UOP
692 367 355 69.9
- Council Bluffs #2 - UOP
624 329 331 65.2
Colorado UTE Electric Assn. Inc. - Hayden #1 - Buell
168 1155 545 775 413 360 70.9
San Antonio Public Service Bd. - J.T. Deely #3 - Buell
430 1362 643 850 454 313
Salt River Project - Hayden #2 - Wheelabrator-Frye
250 1684 795 695 368 335
Omaha Public Power District - Wright #8 - Belco
90 510 241 707 378 320
Nebraska Public Power District
105 541 255 680
Nebraska Public Power District - Sheldon #2 - Belco
120 670 316 710 377 261
Colorado Springs Dept. of Pub. Utilities
137 850 401 710 377
- Sheldon Itl - Belco
360 252
61.6
65.9
63
49.6
Public Service Co. of Colorado - Comanche # 2 - Research-Cottrell
350 2644 1248 690 366 307 60.4 99.5
Wisconsin Power and Light Co., Columbia #1 - Research-Cottrell
520 2770 1307 810 432 269 53 99.5
Iowa Public Service Co. - George Neal #1 - Research-Cottrell
138 691 326 680 360 220 43.3
Southwestern Electric Power Co. - Cason #1 - Research-Cottrell
528 3025 714 750 399 323 65.6
City of Cedar Falls, Iowa - Streeter - Research-Cottrell
40 248 117 802 427 267 52.6
Salt River Project - Navajo #1 - Joy-Western
750 3940 1860 662 350 307 60.4
Salt River Project - Navajo #2 - Joy-Western
750 3940 1860 662 350 307 60.4
Salt River Project - Navajo #3 - Joy-Western
750 3940 1860 662 350 307 60.4
Public Service Co. of New Mexico - San Juan #1 - Joy-Western
330 2800 1322 700 371 398 78.3
Public Service Co. of New Mexico - San Juan #2 - Joy-Western
51.4
- Martin Drake #7
292 57.5
99.4
99.6
99.6
97.9
91
99
99
97.9
- American Standard
99.35 99.2
Operating and/or Maintenance Problems
Low secondary voltages and currents;
ixpansion problems
Low secondary voltages and currents
.earing side plate failure; ash
buildup on plates
ire failure
High ash levels in hoppers; expansion
problems; velocity distribution;
low secondary voltages and currents
Swinging plates; wire failure; rapper
control failure; high voltage
insulator failure
Ash handling; low secondary voltages
and currents
Wire failure; structure failure
Low secondary voltages and currents
Wire failure
(continued)
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TABLE 1 (.continued;
UTILITIES WHICH BURN LOW-SULFUR COAL AND HAVE HOT-SIDE ELECTROSTATIC PRECIPITATORS UNDER CONSTRUCTION
Design
Volume Flow Temperature
MW's KACFM AmVmin °F °C ft2/KACFM m2/(m3/sec)
Houston Lighting and Power Co. - W.A. Parish #5 - Joy-Western
660 3357 1585 719 382
Houston Lighting and Power Co. - W.A. Parish #6 - Joy-Western
660 3357 1585 719 382
Upper Peninsula Power Co. - Presque Isle #7 - Joy-Western
80 530 250 730 388 159 31.3
Upper Peninsula Power Co. - Presque Isle #8 - Joy-Western
80 530 250 730 388 159 31.3
Upper Peninsula Power Co. - Presque Isle #9 - Joy-Western
80 530 250 730 388 159 31.3
Gulf States Utilities Coi - Roy S. Nelson #5 - Joy-Western
540 3090 1458 800 427
Salt River Project - Coronado #1 - Joy-Western
350 2800 1322 760 404 307 60.4
Salt River Project - Coronado #2 - Joy-Western
350 2800 1322 760 404 307 60.4
Central Power and Light Co. - Coletocreek #1 - Joy-Western
550 3738 1764 677 358
Iowa Public Service Co. - George Neal #4 - UOP
575 4200 1982 780 416 420 82.7
Test
Efficiency Efficiency
% %
2 WvW ^
> 99.89 Jjtn
} P^W*****-
99.89
99.2
99.2
99.2
99.5
99.875
99.875
99.6
^fS^
Under construction
Under construction
Under construction
Under ' cons truction
Under construction
Under construction
Under construction
Under construction
Under construction
Under construction
Omaha Public Power District - Nebraska City Station - Wheelabrator-Frye /^ Q'\$J(jfyj~*J
575 3540 1671 755 402 ^350 68.9
Northern Indiana Public Service Co. - Schahfer #14 - PCW
487 2474 1168 660 349 326 64.2
Arkansas Power & Light Co. - White Bluff St. #1 - PCW
800 5141 2427 815 435 370 72.8
Arkansas Power & Light Co. - White Bluff St. #2 - PCW
800 5141 2427 815 435 370 72.8
Arkansas Power & Light Co. - White Bluff St. #2 - PCW
800 5141 2427 815 435 370 72.8
Arkansas Power & Light Co. - White Bluff St. #2 - PCW
800 5141 2427 815 435 370 72.8
99.3 ' f
99.6
99.5
99.5
99.5
99.5
Under construction
Under construction
Under construction
Under construction
Under construction
Under construction
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Unit Description
Units 1, 2, and 3 at the Navajo Generating Station are C-E
supercritical, combined circulation, radiant, reheat steam genera-
tors with a center water wall dividing the furnace into two halves.
The units are designed to deliver superheated steam at a rate of
40822.5 Kg/min (5,400,000 pounds per hour) (maximum continuous)
at 576.1°C (1005°F) and 252.4 kg/cm2 (3590 psig) (superheat
outlet) to a 750 MW turbogenerator. The reheater is designed
to handle 36664.7 kg/min (4,850,000 pounds per hour), reheated
from 306.1°C (583°F) to 538.9°C (1002°F).
The unit, which is a divided furnace design, has each furnace
half fired through four tilting tangential windbox assemblies.
The main fuel (coal) can be admitted to the furnace through seven
elevations of pulverized coal nozzles. Six elevations of Oil Eddy
Plate ignitors and one elevation of retractable warm-up oil guns
are provided for lighting off and warming up the unit and for
ignition of the pulverized coal admitted through adjacent nozzles.
Table 2 provides predicted performance data for the boiler system.
Precipitator Description
The electrostatic precipitators installed on units 1, 2, and
3 at the Navajo Generating Station were designed by the Western
Precipitation Division of Joy Manufacturing Company. Each pre-
cipitator consists of two levels (Figure 1) with eight chambers
per level (Figure 2). The total unit was designed to operate
with a volume flow rate of 1859.68 m3/sec (3,940,000 acfm) at
350°C (662°F) with 99.5 percent collection efficiency.
Each of the sixteen isolatable chambers consists of six
electrical fields in the direction of gas flow and thirty-five
gas passages spaced 22.86 cm (9 in) apart. The collection
electrodes in each of the six fields are 1.8288 m (6 feet) in
depth and 9.144 m (30 feet) high. The discharge electrodes have
a diameter of 2.68 mm (0.1055 inches) and the average spacing
between each wire per field is 22.86 cm (9 inches) [8 wires per
gas passage per 1.83 m (6 ft) field]. Each precipitator is
powered by 48 transformer rectifiers, and each transformer
rectifier powers parallel fields in parallel chambers (Figure 2).
Each precipitator has a total collecting area of 112371.84 m2
(1,209,600 ft2) which results in a design specific collection
area (SCA) of 60.43 m2/(m3/sec) (307 ft2/1000 acfm).
Transformer-Rectifiers—
The high voltage direct current power for the precipitator
discharge electrodes is provided by General Electric Full Wave
Transformer Rectifier Sets. These sets are located on the roof
of each precipitator and are connected to the high voltage dis-
charge electrodes through a ventilated, ducted system of high
voltage lines.
8
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TABLE 2
PREDICTED PERFORMANCE OF UNITS 1, 2, and 3 OF THE NAVAJO
GENERATING STATION, PREPARED BY COMBUSTION ENGINEERING, INC.
Predicted Performance*
Fuel
Evaporation
Feedwater Temperature
Superheater Outlet Temperature
Superheater Outlet Pressure
Superheater Pressure Drop
Reheater Flow
Reheater Inlet Temperature
Reheater Inlet Pressure
Reheater Outlet Temperature
Reheater Pressure Drop
Economizer Pressure Drop
Gas Drop, Furnace to
Econ. Outlet
Gas Drop, Econ. Outlet to
A.H. Outlet
Gas Temp., Entering Air
Heater
Gas Temp., Leaving Air
Heater, Uncorr.
Gas Temp . , Leaving Air
Heater, Corr.
Air Temp., Entering Air
Heater
Air Temp., Leaving Air
Heater
Air Press. Entering Air
Heater
Ambient Air Temperature
Excess Air Leaving Economizer
Fuel Fired
Efficiency
Ib/hr
Kg/hr
°F
°C
°F
°C
psig
Kg/cm2
psi
Kg/cm1
Ib/hr
Kg/hr
op
«C
psig
Kg/cm2
op
°C
psi
Kg/cm2
psi
Kg/ cm2
"wg
mmHg
"wg
mmHg
op
°C
op
°C
op
«C
op
•c
op
oc
"wg
mmHg
op
°C
%
Ib/hr
Kg/hr
«
Control
Load
2,700,000
1,224,693
440
227
1005
541
3525
248
53
3.73
2,490,000
1,129,439
495
257
345
24
1002
539
15
1.05
25
1.05
2.90
5.42
2.95
5.51
560
293
211
99
201
94
70
21
508/522
264/272
5.80
10.84
70
21
30
355,000
161,024
89.52
M.C.R.
Pulverized Coal
5,400,000
2,449,386
507
264
1005
541
3590
252
207
14.55
4,850,000
2,199,912
583
306
676
48
1002
539
30
2.11
39
2.74
7.45
13.92
7.55
14.10
658
348
260
127
250
121
70
21
582/609
306/321
10.90
20.36
70
21
18
652,000
295,741
88.77
M.C.C.
5,535,000
2,510,621
508
264
1005
541
3600
253
217
15.26
4,972,000
2,255,249
587
308
684
48
1002
539
31
2.18
40
2.81
7.67
14.33
7.78
14.53
662
350
261
127
251
122
70
21
584/610
307/321
11.15
20.83
70
21
18
667,000
302,545
88.75
•Notes: These performance figures are predicted only and are not to be construed as being
guaranteed except where the points coincide with the guarantees.
Operation of this unit in excess of the above specified maximum continuous
capacity (M.C.C.) may result in damage to the equipment and/or increased
maintenance.
Superheat steam temperature control range is from 1,224,693 to 2,449,386 Kg/hr
(2,700,000 to 5,400,000 Ib/hr)
Reheat steam temperature control range is from 1,129,439 to 2,199,912 Kg/hr
(2,490,000 to 4,850,000 Ib/hrJ
Control Load - half load control point
M.C.R. - Maximum Continuous Rating
The fuel specifications on which the guarantees are based are as follows:
Black Mesa Sub-Bituminous Coal H.H.V. 5958,3 Cal/g (10,725 BTU/lb)
C
H
O
N
S
Ash
Moist.
Cl
61.29*
4.37
12.13
1.00
0.50
10.43
10.27
0.01
Fixed Carbon
Volatile
Moisture
Ash
Total
41.364
37.94
10.27
10.43
100.00*
Total
100.00%
-------
Figure 1. Ductwork and precipitator arrangement for Navajo
Station, Unit 3.
10
-------
UPPER
TR Set Typical, 48 Total
4 3
H-
i£3
C
I-!
CD
; uu u u u u
CD
O
H-
'O
H-
rt
OJ
rt
O
H
O
tr
03
c
D
E
F
G
H
C
D
E
F
G
H
SOUTH
NORTH
" •"u"u"u"u"u"
(D
G
H
1 + 3S 1 -* 35^*n -»- 35
1 -»• 3 5 ~V 1 ^. 35
D
tages G
H
LOWER
-------
The transformer rectifier unit consists essentially of a
high-voltage transformer core and coil, silicon rectifier and a
high-voltage switch all contained in a common oil filled tank.
The primary (low-voltage) winding of the transformer consists of
a single coil. The secondary (high-voltage) winding of the
transformer consists of a single coil in a continuous layer-
wound arrangement.. The function of the transformer is to step
up the AC supply voltage to the desired value before rectifying
it by means of the silicon rectifier unit. The silicon rectifier
unit is a full-wave bridge circuit with its output connected to
the high voltage bushings.
There are a total of 48 transformer rectifier sets (24 on the
upper precipitator and 24 on the lower precipitator), each of which,
as stated previously, powers parallel fields in parallel chambers.
The transformer rectifiers which power fields "H" and "G" are
rated at 45 kV and 1000 ma with a reactor rating of 75 kVA. The
transformer rectifiers which power fields "F" and "E" are rated
at 45 kV and 1200 ma with a reactor rating of 87.5 kVA. The
transformer rectifiers which power fields "D" and "C" are rated
at 45 kV and 1600 ma with a reactor rating of 112.5 kVA.
Rapping System--
The rappers which are used to remove the collected particu-
late from the collecting and discharge electrodes, are electro-
magnets which are operated by pulsating direct current. The
rappers are operated automatically by a matrix type rapper con-
trol system which is capable of varying the "ON" and "OFF" time
between the operation of each rapper and the intensity of each
rapping pulse.
Figure 3 represents the rapping control program boards for a
typical chamber of the precipitator as originally installed. The
original rapper program had approximately five minute relays which
controlled all the wire and plate rappers in two adjoining fields
of one chamber. The first row of the program board controlled
all the rappers on fields H and G, the second row controlled the
rappers in fields F and E, and the third row controlled the
rappers in fields D and C.
The rapping program steps through each relay until it reaches
the end of the second program board or a homing pin and then
returns to the first relay in the first programming board. The
total time for each cycle of the original rapping program was 100
minutes; and during that 100 minutes the first two fields were
rapped nine times, the third and fourth fields five times, and
the last two fields four times. Prior to Phase I of the test
program, the Salt River Project changed the rapping control pro-
gram boards to separate the wire 'and plate rappers so all rappers
in one field would not operate sequentially.
12
-------
ORIGINAL RAPPER SETTING CHAMBERS 7 & 8
FIELDS
PROGRAM CARD NO. 1
PROGRAM CARD NO. 2
H&G
F&E
D&C
,
CHAMBEF
1&5
2&6
3&7
48,8
CHAMBEI
1&5
2&6
3&7
4&8
CHAMBER
1&5
2&6
3&7
4&8
^
FIELDS
G&H
E&F
C&D
5:00
7
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:00
5:07
5:03
5:00
5:00
9
< .
J»-'
MODIFIED RAPPER SETTING, UPPER PRECIPITATOR HOMING PINS^
IS FIELDS C&D
7:40
?
6:45
6:35
8:45
6:40
9:45
6:45
8:45
7:45
7:46
7:50
7:30
7:00
7:40
8:40
7:50
0
0
0
0 ^
IS FIELDS E&F
2:30
7
3:15
3:15
3:30
3:05
3:40
3:20
3:20
3:20
3:20
6:
rn
3:20
3:20
3:30
4:10
0
'
0
0
0^
S FIELDS G&H
2:50
•
2:50
2:50
2:50
2:50
2:50
2:55
2:50
2:45
2:50
2:30
3:00
2:40
2:50
3:10
2:40
0
0
0
0 "
WIRES
3:20
r
3:30
3:40
3:30
3:30
3:30
3:35
3:35
3:30
3:35
3:25
3:30
3:35
3:25
3:40
2:00
0
0
0
0 -
TIMES FOR RELAYS ARE APPROXIMATE
Figure 3. Rapper control settings
(times in minutes)
13
-------
Figure 3 presents the rapping program cards and the changed
rapping program for the upper half of the precipitator. Although
this change separated the wire and plate rappers from one relay
of a control card, it is possible for all rappers of one chamber
(wires and plates) to be activated during the time span of one
relay since each rapper control program operated independently
of the others.
Ash Handling System—
After collection in the precipitator hoppers, the fly ash
passes through pressurized type Nuva feeders into a pressurized
pipe and is transported under pressure to the fly ash storage bin.
The storage bin is equipped with a fabric filter dust collector
on the low pressure or vented side of the bin. From the storage
bin the ash is conveyed to the fly ash loading area where it is
loaded into trucks for transport to the ash fill area. As the
ash is loaded into the ash trucks a water spray is used to
minimize the loss of ash during loading and transport to the
fill area.
The precipitator ash conveying system is a nearly continuous
operation. The control system for the Nuva feeders steps through
its program from one feeder to another whenever the pressure drop
across a Nuva feeder reaches a predetermined minimum.
TEST PROGRAM
The test program for the Unit 3 precipitator was designed to
evaluate the precipitator as a whole and one of the sixteen
isolatible chambers. The test program was conducted during July
and August of 1977, and all testing was performed at night due to
the extreme temperatures at the sampling locations during daylight
hours.
Phase I
Phase I of the test program was conducted from July 10 through
July 23, 1977, and consisted of an evaluation of Chamber No. 8.
Particle size measurements were obtained with impactors at the
inlet and outlet sampling locations for fractional efficiency
determinations, and total mass loadings were obtained with mass
trains to enable calculation of overall mass efficiency. Gas
composition data, including S02 and SO3 analyses, were obtained
at the outlet of Chamber No. 8. Ultrafine particle size data with
an Electrical Aerosol Analyzer were obtained sequentially at the
outlet and inlet sampling locations of Chamber No. 8 for frac-
tional efficiency determinations for particle diameters less than
0.5 ym. Five-stage series cyclones were operated sequentially at
the inlet and outlet sampling locations to obtain samples for
ion-excited x-ray analysis in order that elemental composition as
a function of particle diameter could be determined. Boiler
14
-------
operating data, hourly secondary voltages and current readings,
coal samples and ash samples from Chamber No. 8 and the Unit 3
ash silo were obtained during each test day. Secondary voltage-
current curves were obtained on each of the six transformer
rectifiers which powered Chambers 7 and 8. Figure 4A illus-
trates the time of operation and location of the ultrafine
sizing systems and each impactor run during Phase I and Phase II
of the test program. Figure 4B illustrates the time of operation
and location of each mass traverse during, the test program. Also
illustrated in Figures 4A and 4B are the times for soot blowing
and valve testing. The valve tests were required of the unit
operators and resulted in the decrease of unit load to approxi-
mately 750 MW.
Phase II
Phase II of the test program was scheduled to be conducted
from July 31 to August 14, 1977. Tests scheduled for August 5
and 6 were cancelled due to operational problems with Unit No. 3
and on August 8, after conferring with the project officer, the
remainder of the test program was cancelled. Tests which were
scheduled during Phase II included particle size measurements,
with impactors and ultrafine equipment, at the main inlets and
stack, mass train measurements at the main inlets and stack,
resistivity measurements ahead of and downstream from the air
preheaters, voltage current readings, gas analyses, and cyclone
samples obtained with the five-stage series cyclones for ion-
excited x-ray analysis.
During the first week of Phase II, cyclone samples were
obtained at the main inlet and impactors were operated at the
main inlet and stack sampling locations. Voltage-current readings
and gas analysis data were also obtained during the first week of
Phase II. Resistivity measurements scheduled for the first week
of Phase II were not obtained due to material failure problems
in the "Hot" Probe. The resistivity data scheduled to be obtained
downstream from the air preheaters during the second week of
testing was later obtained on August 21-23, 1977. Due to the
plant outage, no overall efficiency measurements with mass trains
were obtained. Opacity data, which were scheduled to be measured
at the stack coincident with mass train traverses, were also not
obtained.
MEASUREMENT TECHNIQUES
Brief descriptions of the measurement techniques are given in
the following sections. More detailed discussions and example
calculations are given in the Appendix.
15
-------
JULY
2100 2130 2200 2230 230C 2330 2400 0030 0100 0130 0200 0230 0300 0330 0400 0430 0500 0530 0600 0630 0700
12-13
13-14
14-15
..'.'-'-'- .TU 14 J .•]•••
I U-l- :"..-.'."..-. :•!
uiflnmll' fTlliinrhirTTT
INLET IMPACTORS
OUTLET IMPACTORS
ULTRAFINE - OPTICAL —
ULTRAFINE - EAA
SOOT BLOWING
"• VALVE TESTING, UNIT
1 LOAD DECREASED "v 50MW
61FPRWJ3I 608
Figure 4a. Chronological display of impactor and ultrafine measurements.
-------
JULY
2100 2130 2200 2230 2300 2330 2400 0030 0100 0130 0200 0230 0300 0330 0400 0430 0500 0530 0600 0630 0700 0730
12-13
13-14
14-15
15-16
16-17
18-19
19-20
20-21
21-22
jKl INLET 5
OUTLET 5
INLET 6
L
OUTLET 6
INLETS
OUTLET 8
INLET 10I:"-™™*
i r*
OUTLET 1
LET 13
INLET MASS TRAIN
OUTLET MASS TRAIN
SOOT BLOWING
j VALVE TESTING, UNIT LOAD
DECREASED'VSOMW
I I I
INLET 14 t
I
OUTLET
INLET 16
I
OUTLIJT 10
I
Figure 4b. Chronological display of mass train measurements.
-------
Mass Measurement
Mass loading determinations were conducted at the inlet and
outlet sampling locations of Chamber No. 8. Alundum in-stack
filters were used at the inlet while Gelman 47 mm filters were
used in-stack at the outlet to collect the particulate mass.
Thirty-six and forty-two point isokinetic traverses were con-
ducted across the inlet and outlet sampling locations, respectively.
Impactor Measurements
Calibrated cascade impactors were used at the inlet and
outlet sampling locations to obtain particle size and particle
mass distributions for particles between approximately 0.50 ym
to 10 ym. Modified Brink Cascade Impactors were used at the
main precipitator inlet and the inlet to Chamber No. 8 while
Andersen Mark III Cascade Impactors were used at the outlet of
Chamber No. 8 and the stack sampling location. Glass fiber
substrates which were conditioned in the laboratory, by acid
washing, and in situ, by passing filtered flue gas through them,
were used in all impactors. Blank impactor runs were conducted
each test day for each type of impactor with the exception of an
Andersen Blank on the first test day. The blank impactor runs
were conducted at approximately the same flow rate (1.4xlO~5
m3/sec (0.03 cfm) for the Brink and 1.9xlO~" m3/sec (0.4 cfm)
for the Andersen) and for approximately the same sample time
K30 minutes for the Brink and ^ 150 minutes for the Andersen) as
the "real" sampling runs. Data reduction was performed with a
computer program described in Reference 1.
Ultrafine Size Measurements
A Thermo-Systems, Inc. Model 3030 Electrical Aerosol Analyzer
(EAA) was used sequentially at the outlet and inlet sampling
locations of Chamber No. 8 and at the stack sampling location to
determine concentration vs. size information in the diameter
range of 0.015 ym to approximately 0.30 ym. The operating prin-
ciple of the EAA2 is based on placing a known charge on the
particles and then precipitating the particles under closely
controlled conditions. Size selectivity is obtained by varying
the electric field in the precipitator section of the mobility
analyzer. The mobility of charged particles is monotonically
related to particle diameter in the operating regime of the instru-
ment. An optical single particle counter (Royco 225) was used in
parallel with the mobility analyzer to provide particle size dis-
tribution data over the approximate particle diameter range from
0.3 to 2 ym.
A dilution system is required for the EAA and Royco because
the sizing instrumentation cannot tolerate raw flue gases as
sampling streams nor cope with particle concentrations encountered
in flue gases. The required dilution typically ranges from 10:1 to
1000:1 depending upon the particulate source and the location of the
sampling point with respect to the control device.
18
-------
Resistivity Measurements
In situ resistivity measurements were conducted with a
point-to-plane electrostatic collection instrument3 at the main
inlet of Unit #3 and downstream from the air preheater. The de-
vice is inserted into the flue gas environment and allowed to
reach near thermal equilibrium with the gas stream. The dust
thickness gage is set at zero and the measurement cell positioned
for collection. A clean electrode voltage vs. current character-
istic is recorded. The current density for collection is
selected and a dust layer is precipitated electrostatically.
After collection of the dust layer has occurred, a second vol-
tage vs. current characteristic is recorded. A comparison of
the two voltage-current curves provides one method for deter-
mining resistivity in the absence of electrical breakdown in the
dust layer. The measurement electrode is then lowered to con-
tact the dust layer and the layer thickness is determined. The
resistance of this known geometrical configuration (right cylinder)
is measured, and the resistivity is then determined from the mea-
sured resistance.
Laboratory resistivity measurements were conducted on ash
samples collected from the "A1 hopper of Chamber No. 8 and the
Unit No. 3 ash silo. The laboratory resistivity measurements
were conducted in an ASME Power Test Code 28 type apparatus3 and
a controlled laboratory environment.1*
Gas Composition Determination
Gas analysis measurements were conducted at the inlet and
outlet sampling location of Chamber No. 8, at the main inlet, and
at the stack. Commercial Orsat-type analyzers were used for oxygen
and carbon dioxide determinations. The moisture content of the
flue gas was determined at the outlet sampling locations by pulling
a known volume of gas through a preweighed packed drierite column.
The drierite column was then weighed and the moisture content
calculated from the weight change. The concentrations of sulfur
trioxide and sulfur dioxide were also determined at the outlet
sampling locations. The sulfur trioxide samples were collected by
a condensation method5 while the sulfur dioxide was collected in
a hydrogen peroxide solution, which oxidized the sulfur dioxide
to sulfur trioxide. Each of the sampling techniques for the oxides
of sulfur produced a sample for analysis that consisted of a dilute
sulfuric acid solution. The concentrations of acid (from which
the SOX concentrations may be calculated) were determined by
barium perchlorate titration using thorin indicator.
Cyclones Used for Obtaining Samples for Ion-Excited X-Ray Analysis
Five-stage series cyclones were used to obtain size frac-
tionated samples for ion-excited x-ray analysis.6 The cyclones
were operated at one point in the flue and at an average isokinetic
19
-------
flow rate. The particulate catch from the cyclones was analyzed
by the University of California's Crocker Nuclear Laboratory in
Davis, California. The elemental analysis system7 is based on
ion-excited x-ray emissions (IXA) and provides a sensitivity
over a wide range of elements.
Voltage-Current Measurements
During Phase I, primary and secondary voltages and currents
were recorded from the transformer control cabinets which powered
chambers 7 and 8. Voltage divider resistor assemblies were attached
to the high voltage side of each of the transformers of chambers
7 and 8 and secondary voltage vs. current curves were obtained
during Phase I. Photographs of voltage waveforms were also
obtained.
During Phase II of the test program, primary and secondary
voltages and currents were recorded for each of the forty-eight
transformer control cabinets.
TEST RESULTS
Mass Train Measurements
Since the test program was conducted on a hot-side precipita-
tor upstream from the air heater, there was concern that boiler
soot blowing operations could significantly influence the particu-
late concentration. Therefore, mass train and impactor runs were
scheduled to occur in soot blowing and non-soot blowing periods,
as indicated in the chronological displays of Figures 4A and 4B.
Table 3 contains the mass concentration data obtained with the
mass trains and impactors during Phase I. Also included are gas
flows, temperature, and 02 and CC>2 concentrations obtained with
the mass train and gas analysis systems. The calculated values of
precipitator collection efficiency are included when appropriate,
along with the specific collecting area, which is based on an
average of the inlet and outlet actual gas flow rates.
The inlet and outlet gas flows indicate that a significant
in-leakage of air occurs across the chamber, accompanied by a
temperature drop. Since this apparent leakage had been noted in
a previous test series on Chamber 8 and indicated approximately
8% in-leakage accompanied by a 29°C temperature drop, the inlet
and outlet temperature and pitot systems were checked against
one another at the outlet sampling location prior to starting
the test series. The pitot systems were found to be in agreement
when checked at the same point, and the temperature measuring
systems were within 2°C of one another. A comparison of average
inlet and outlet temperatures, oxygen contents, mass loadings,
and gas flows for the Phase I test series is given in Table 4.
The data in Table 4 indicate that the average outlet volume flow
is 16% greater than the inlet.
20
-------
MASS CONCENTRATIONS OBTAINED DURING PHASE I
WITH MASS TRAINS AND IMPACTORS
Date
Run 1
INLET
Temp. •€
02
COs
Vol. Flow, dsm'/sec
'Grain Loadings)
Mass Train/ g/dsms
Impactors, g/dsm1
OUTLET
Temp. °C
0,
CO,
Vol. Flow, dam'/sec
Grain Loadings;
Mass Train, g/dsm'
Impactors, 'g/dsm1
SCA1, mVlm'/sec)
Efficiency, «
Mass Trains
Impactors
7/12-13/77
1 1A
S1 NS
350.0
4.2
13.7
44.31
5.4849
1.5355 2.5186
324.4
4.3
15.1
50.96
0.0522
0.0496
53.32
99.05
98.03
7/13-14/77 .
22
S
362
3.5
15.0
45.
6.0852
4.4721
331.1
5.4
14.6
51.68
0.0531
0.0320
52.23
99.13
99.28
f
NS
.2
5.6
14.0
54
5.1754
4.0658
335.0
4. 8
14.7
51.59
0.0693
0.0291
52.59
98.66
99.28
7/14-15/77
4
S
366.1
5.0
13.7
43.28
8.1375
5.3302
333.9
6.2
14.2
51.41
0.0401
0.0327
53.44
99.51
99.39
5
NS
362.8
5.4 •
13.6
45.03
5.9126
3. 3374
330.0
5.4
14.2
50.08
0.0412
0.0190
52.90
99.30
99.43
7/15-16/77
6
S
360.0
3.8
14.9
44.75
8.3778
7.3689
331.1
4.3
15.1
50.20
0.0336
0.0333
53.24
99.60
99.55
7
NS
.360.6
4. 0..
15.2
44.62
6.8727
—
330.6
5.3
14.1
51.56
0.0403
0.0194
53.11
99.41
—
7/16-17/77
8
S
366.1
3.8
15.0
44.62
6.8061
5.8501
337.2
4.5
15.2
51.46
0.0680
0.0532
51.57
99.00
99.09
9
NS
363.3
4.2
14.7
44.56
6.0845
...
331.7
5.3
14.0
52.24
0.0732
0.0270
51.84
98.80
—
7/18-19/77
10
S
353.3 .
3.7
14.8
44.35
7.3962
4.2335
325.0
4.6
15.1
52.62
0.0838
0.0477
52.60
98.87
98.87
11
NS
352.8
4.2
15.0
44.89
6.6988
—
326.1
4.*
14.6
52.30
0.0423
0.0256
. 52.19
99.37
—
7/19-20/77
12
S
367.2
3.9
15.0
44.40
7.3296
6.4838
333.3
4.4
14.8
52.21
0.0391
0.0437
51.96
99.47
99.32
13
NS
367.8
4.2
14.7
44.83
5.5977
4.9456
331.1
4.8
14.7
51.99
0.0414
0.0383 .
52.13
99.26
99.23
7/20-21/77
14
S
364.4
4.2
14.9
44.21
6.7874
5.9307
331.7
5.3
14.3
51.17
0.0515
0.0299
53.05
99.24
99.50
15
NS
363 . 9
4.2
14.5
43.60 .
7.5626
~
329.4
4.7
14.5
51.33
0.0744
0.0770
52.92.
99.02
—
7/21-22/77
16
NS
366.1
4.2
14.7
43.17
8.0262
5.6458
328.9
4.1
15.3
51.51
0.0423
0.0439
53.15
99.47
99.22
1. S denotes testa which were conducted while soot blowers were operational, whereas, NS denotes non-soot blowing test periods.
2. Inlet mass train and impactor data obtained from a two point, one port traverse.
3. Calculated.by averaging the inlet and outlet volume flow and using a collection area of 7023.24m2
4. Inlet mass train and impactor data obtained from a two port, two points per port, traverse.
-------
TABLE 4. AVERAGE INLET AND OUTLET PARAMETERS
CHAMBER 8
Temperature, °C
Vol. Flow, dsm3/sec
02, % (dry basis)
Mass Concentrations, g/dsm3
Impactor
Mass Train
Number of Runs
Impactor
Mass Train
Inlet
361
44.4
4.26
5.19
6.77
27
16
Outlet
330
51.5
4.88
0.0384
0.0529
32
16
Average Collection
Efficiency, %
99.26
99.22
TABLE 5. STATISTICAL ANALYSIS OF EFFECT OF SOOT
BLOWING ON MASS EMISSION - PHASE I SERIES
CHAMBER 8
Inlet
Outlet
x,
a,
Y
t
g/dsm3
g/dsm3
tg 9
tg e
t95
t g o
t 80
Mass Trains
NS S
6.38 7.28
0.98 0.80
16
2.02
2.92
2.58
2.12
1.75
_
Impactors Mass Trains
NS S NS S
4.32 5.62 0.0530 0.0527
1.81 2.00 0.0150 0.0178
20 14
1.70 0.036
2.84 t50 0.692
2.53
2.09
1.72
1.32
Impactors
NS S
0.0377 0.0393
0.0189 0.0102
28
0.306
0.683
x = average of sample
a = standard deviation
y = degrees of freedom
t = Student's "t" value
t = Critical t value for y at indicated confidence level
22
n
-------
Since the difference in inlet and outlet flows was unexpectedly
large, in-leakage was further examined by performing an adiabatic
mixing calculation to determine the air in-leakage necessary to
cause the observed temperature drop. The calculation demonstrates
that 11% in-leakage would be required to produce the observed 31°C
temperature drop in the absence of other heat losses using the
measured inlet flow. Since other losses to ambient air would
occur, the temperature profile averages indicate that in-leakage
must be less than 11%. The oxygen concentrations determined by
single point analyses during the mass train tests indicated in-
leakage of about 7%. We conclude that, since the mass train sys-
tems were checked against one another, a part of the difference
in indicated flow results from integration errors in obtaining
the true flow from a limited number of traverse points. The actual
in-leakage is estimated to range between 7 and 11%.
The mass concentration data were analyzed to determine whether
soot blowing operations in the boiler significantly increased total
particulate loadings. Average particulate concentrations and
sample standard deviations were computed for the with and without
soot blowing data sets for both the mass train and impactor
sampling systems. A procedure given by Hoel8 was used to estimate
the "t" variable and the number of degrees of freedom required for
using the Student's "t" distribution to examine the difference of
two means. The results of these calculations are given in Table 5,
and the following conclusions are apparent:
& The mass train data indicate significant mass loading
increases during the soot blowing periods at the 90%
confidence level.
o Similarly, the impactor-derived mass concentrations show
an increase during soot blowing at the 80% confidence
interval.
© No significant differences were observed as a result
of soot-blowing by either sampling system at the pre-
cipitator outlet.
Previous test results had indicated unusually large disagree-
ment between impactor and mass train determinations of inlet mass
loadings for Chamber 8 which were thought to result from stratifi-
cation in the duct. Therefore, an experiment was conducted in
which the modified Brink impactors were operated at an average
isokinetic flow rate for two points in a single port for a total
sampling time of 30 minutes. Mass train sampling, also for a
total of 30 minutes, immediately followed the impactor sampling,
but the mass train was operated isokinetically at the two points.
The experiments were repeated for ports 1, 2, and 3; and the results
are presented in Table 6. The results indicated that the ratio of
impactor to mass train total concentrations were within the expected
range for coal-fired power boilers. All other runs with impactors
23
-------
Table 6
Comparison of Inlet Mass Train and Irapactor Loadings
Date 7/13-14/77
Phase I Average,
Port # 1*23 All Other Runs
Impactor
mg/dsm3 4472 4809 3322 5232
Mass Train
mg/dsm3 6085 5628 4723 6934
Ratio of
Impactor/Mass Train .735 .854 .703 .755
* Loadings from Ports 1, 2 and 3 were obtained from a two point
traverse, the impactors were operated at an average isokinetic flow
rate and the mass trains were operated isokinetically. Each system
was operated for 30 minutes per port. The mass train immediately
followed the impactor at each port.
Table 7
Phase II, Main Inlet and Stack Impactor Mass Loadings
Date 8/2-3/77 8/3-4/77 8/4-5/77
Condition1 S NS S NS S NS
Main, g/dsm3 2.2958 4.5175 6.0185 4.4645 5.0123 8.5836
Stack, g/dsm3 0.0546 ~ 0.0525 0.0678 0.0851 0.1244
1S = Soot Blowing, NS = Non Soot Blowing
24
-------
at the inlet were conducted with either a five- or six-point
traverse per port; whereas, the mass trains always conducted a
six-point traverse for each port.
Outlet sampling with the Andersen impactors was conducted by
obtaining a six point traverse per port, which was the same pro-
cedure used with the mass trains. The Andersen impactors tra-
versed the entire duct, and therefore were operated at a flow rate
isokinetic to the average velocity in the duct. The mass train
followed the usual procedure of isokinetic sampling at each point.
The data in Table 4 indicate that the impactors obtained 77 and
73% of the total mass sampled by the mass trains at the inlet
and outlet, respectively.
Overall mass efficiency data for the entire precipitator were
not obtained during Phase II as a result of a plant outage, as
was discussed previously. However, impactors were operated at
the stack and at the main inlet sampling locations. The results
obtained are given in Tables 7 and 8. Due to the small fraction
of the total inlet duct that can be traversed with the Brink
impactors during the with and without soot blowing periods, no
conclusions could be drawn concerning the effect of soot blowing
on total inlet mass concentrations from the impactor data. A
comparison of the data in Tables 4 and 8, however, indicate that
the precipitator as a whole was not performing as well as Chamber
8. The volume flow at the stack is consistent with the outlet
flow from Chamber 8 (860/16 = 53.8 dsm3/sec Vs. 51.5 dsm3/sec for
Chamber 8), and the simultaneous oxygen determination at the inlet
and the stack indicate that total in-leakage across the entire
precipitator and the air preheater is approximately 10.7%.
Impactor Measurements
Inlet and outlet impactor sampling was conducted as previously
discussed and as illustrated in Figure 4a to determine precipi-
tator collection efficiency and particulate concentrations as a
function of particle size. In accordance with Particulate Technology
Branch Directives, blank substrate weight changes were determined
to obtain appropriate blank correction factors for the flue gas -
substrate reactions. The results of the blank runs, which were
conducted in situ simultaneously with the real runs, are summar-
ized in Table 9. The data from all blank determinations are given
in Appendix 2 . The "nozzle wash" weight gains shown in Table 9
result from the evaporation of an amount of distilled water equal
to that used for nozzle washes in the real runs. The distilled
water source used during Phase II apparently contained a signi-
ficant dissolved solids content. The appropriate correction fac-
tors from Table 9 were used prior to the calculation of the size
distributions from the "real" data sets.
25
-------
Table 8
Phase II, Average Inlet and Stack Parameters
(From Impactor Sampling Systems)
Temperature, °C
Vol. flow, dsm3/sec
02, % (dry basis)1
Mass concentration, g/dsm3
Number of runs
Apparent collection
efficiency, %
Inlet
98.56
Stack
368
-
3.90
5.40
12
161
860
5.55
0.0776
10
1
Orsat data from Table 16
Table 9
Average Blank Corrections for Impactor Components
Components
Brink filter
Brink stage
Andersen filter
Andersen stage
Andersen nozzle wash
Phase I
Mass change, mg
0,12 gain
C.07 gain
0.14 gain
0.13 loss
1.60 gain
Phase II
Mass change, mg
0.12 gain
0.00
0.13 gain
0.32 gain
10. 4-8 gain
26
-------
Figure 5 illustrates the particle size distribution obtained
by the modified Brink impactors at the inlet to Chamber 8 with and
without soot blowing. The data are presented on a differential
basis to illustrate the particulate mass as a function of particle
diameter. Since the area under the DM/DLOGD vs. diameter curve
is directly proportional to particulate concentration, the rela-
tive mass in various size bands can be qualitatively determined
by examination of the curve. The error bars represent fifty
percent confidence intervals. It is apparent that the bars for
the with and without soot blowing periods intersect for most size
intervals smaller than 8.0 ym diameter. The majority of the
difference in mass concentration between the with and without
soot blowing data sets occurs for sizes greater than 8.0 ym
diameter.
The size distribution shown in Figure 5 is typical of the bi-
modal distributions produced by pulverized coal-fired boilers,
with one mode occurring at about 2.0 ym particle diameter, and
the other occurring at a diameter greater than 10.0 ym. The
mass median diameter of the entire distribution, based on the
impactor determinations of cumulative and total mass loading, is
approximately 13 ym. If it is assumed that the difference in mass
loadings between the impactor and mass train sampling systems
results from under sampling of >20 ym diameter particles by the
impactors, the mass median diameter of the distribution increases
to 16 ym. This value is based on the extrapolated cumulative mass
loadings obtained from the impactor data reduction program and the
total particulate concentration obtained with the mass train.
In view of the relatively small differences indicated in
Figure 5 between the with and without soot blowing data sets in
the size ranges of interest, the results from the two sampling
periods were combined. Figure 6 provides the grand average
differential size distributions obtained during Phase I and II
at the Chamber 8 and at the main inlets, respectively. These
distributions are also given on a cumulative mass concentration
basis in Figure 7. The data sets obtained at the two locations
indicate some departure from each other in the differential mass
loadings in the 1 to 2 ym diameter region, but the cumulative
distributions are nearly identical.
In contrast to the similarity observed between size distri-
bution data obtained at the main inlet and the Chamber 8 inlet,
significantly different results were obtained at the stack loca-
tion compared to those of the previous test series at the Chamber
8 outlet. The outlet differential size distributions are illus-
trated in Figure 8. Although the distributions tend to merge at
approximately 0.8 ym diameter, the stack outlet data exhibit sub-
stantially higher loadings from 0.8 to >10.0 ym particle diameter.
These differences are also reflected in the fractional efficiency
results given in Figure 9. The apparent fractional efficiency
data representing the entire precipitator necessarily includes
the influence of any size distribution changes which result from
cooling the flue gas and passing it through the preheater. The
data obtained with the ultrafine system is discussed in the next
section. 27
-------
IKUET CHAFER B USIT 3
7/1E-S/77
10s-
a
103-
a
en
a
a
a
10P-
©SOOT BLOWING
ONON SOOT BLOWING
OQ,
1H
UTL •
f
o
5
-\ 0—HH-H-H 1 J—HH-H-H 1 J—HH-H-H
1CT1 10° 101 105
PARTICLE DIAMETER (MICROMETERS)
Figure 5. Differential size distributions, Chamber 8 inlet.
28
-------
HOT 3 GWW AVERAGE 7/12-ffi/77
a
LD
a
a
a
_LUH
1C*
•
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a 9
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a 5^5- J
1 '*/ !ii'*
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r1 10° lo1 ic
PARTICLE DIAMETER (MICROMETERS)
Figure 6. Average inlet differential size distribution,
29
-------
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PARTICLE DIAMETER (MICROMETERS)
Figure 7. Average inlet cumulative size distribution.
30
-------
urn 3 asta
a
LD
a
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H — i M i
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• OUTLET-STACK, 8/2-5/77
O CHAMBER 8 OUTLET, 7/12-22/77
1 — i ii » ml - 1 — i i i i ml
1CT1 10° 101 10s
PARTICLE DIAMETER (MICROMETERS)
Figure 8. Outlet differential size distribution.
31
-------
PEJCTRATIDN-EFFICIEHry
IMT3
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; CHAMBERS, o ,MPACTOR !
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PARTICLE DIAMETER (MICROMETERS)
Figure 9. Fractional efficiency for Chamber 8
and total ESP.
32
-------
Figure 10 gives the cumulative mass concentration as a func-
tion of particle diameter obtained during Phase II at the stack
sampling location. The outlet size distribution represents cumula-
tive mass emissions of approximately 4.73 ng/J (0.011 lb/106 Btu),
9.03 ng/J (0.021 lb/106 Btu), 22.36 ng/J (0.052 lb/106 Btu), and
30.79 ng/J (0.0716 lb/106 Btu) at particle diameters of 1.0, 2.0,
10.0, and 100.0 ym respectively. The largest particle diameter is
an arbitrarily chosen upper limit at which the total particulate
mass concentration is plotted.
Ultrafine Measurements
The sample extraction and dilution system with the Electrical
Aerosol Analyzer and optical particle counter was employed sequen-
tially at the outlet and inlet of Chamber 8 during the first week
of Phase I and at the stack sampling location during Phase II.
Figure 11 illustrates the relative variations with time observed
at the" outlet of Chamber 8 for 0.092 diameter particles with the
EAA and for the particle concentrations obtained by the optical
particle counter (operating in a parallel arrangement with the
EAA) over the diameter range 0.36 to 0.59 ym. Similar data
obtained at the stack sampling location are shown in Figure 12,
and Figure 13 shows relative concentrations as a function of
time for 0.092 ym particles at the Chamber 8 inlet. These data
indicate that small particle emission rates exhibit significant
short term temporal variations that are not directly related to
soot blowing operations in the boiler.
Figure 14 contains the differential number size distribution
(AN/ALOGD) calculated for the Chamber 8 inlet sampling location
from the EAA, optical particle counter, and impactor data sets.
The comparison indicates considerable disagreement in the overlap
region, although the data would form a nearly continuous curve if
the ultrafine system points above 0.1 ym diameter are disregarded.
Figure 15 contains AN/ALOGD data from the ultrafine system at the
stack and the Chamber 8 outlet sampling location. These data
indicate that the ultrafine particle emissions at the stack outlet
are not significantly different from those measured at the chamber
outlet. This is consistent with Figure 8 in which the impactor-
derived dM/dLOGD values coincide for the sub-micron range at the
two sampling locations. However, the ultrafine and impactor sys-
tems show disagreement in the overlap region at the stack sampling
location in the same direction as indicated at the inlet in Figure
14. Possible causes of the disagreement are: (1) non-ideal
impactor performance not sufficiently accounted for by existing
calibration procedures at ambient temperature, (2) the effect of
S02 on the results obtained with the EAA (see Marlow9), (3) spatial
concentration variations which influence single point results com-
pared with those obtained by a traverse.
33
-------
OUTLET SWCR Ml 3 EfiKD A%Bft£
CD
§ lO5^:
a
101,:
LJ
10°,:
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TOTAL
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a:
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-H-H+j 1—I 1 t NiH 1—HH-I-H-
1O"1 10° 1O1 10s
PARTICLE DIAMETER (MICROMETERS)
Figure 10. Average outlet cumulative size distribution,
total ESP.
34
-------
20
CHAMBER NO. 8 OUTLET 7/12 - 13/77
10,
9
8
7
o
o
0
in
oc
4,
T
T
T
OPTICAL DATA No. PARTICLES/M3 x 108
••••©»e
EAA DATA (0.092jum PARTICLES)
o«
5MIN -
JL
I
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0020 0120 0220. 0320
J£NON SOOT->|< - SOOT
0420
0520 0620
NON SOOT
0720
Figure 11. Relative concentration of particles with and
without soot blowing, Chamber 8 outlet,
7/12-13/77.
35
-------
20
UNIT NO. 3 STACK. 8/2 - 3/77
10
9
8
01 c
O 5
4
UJ
r
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OPTICAL DATA NO. PARTICLES/M3 x 108
o,
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. EAA DATA (0.092jum PARTICLES)
o©
I
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0100 0200
*r NON SOOT -?
0300
0400
0500
SOOT
0600 0700
0800
Figure 12. Relative concentration of particles with
and without soot blowing, stack location
(8/2-3/77) .
36
-------
CHAMBER NO; 8 INLET. 7/15 - 16/77
10
9
8
<
cc
£ «'
01
O
o ,
O 3
i i r
EAA DATA (0.092fim PARTICLES)
—»j|c 5MIN
J I I
1:
0100 0200 0300 0400 0500 0600 0700 0800
K- SOOT >K NON SOOT —— >
Figure 13. Relative concentration of 0.092 ym particles
with and without soot blowing, Chamber 8 inlet,
7/15-16/77.
37
-------
10"
«-
o
«-
-
a9O1v
I
5
p
-e-
0 EAA
0 ROYCO
A IMPACTORS
10-2 10-1 10° 1Q1
GEOMETRIC MEAN DIAMETER, micrometers
Figure 14. Differential number size distributions,
Chamber 8 inlet.
38
-------
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13
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GEOMETRIC MEAN DIAMETER, micrometers
Figure 15.
Differential number size distribution,
outlet sampling locations.
39
-------
The fractional efficiencies derived from the ultrafine
system data are plotted in Figure 9 along with the inertially-
obtained fractional efficiencies from the impactors. Although
the two measurement methods produce results displaced from each
other, the existence of a minimum collection efficiency as pre-
dicted by theory in the region between 0.1 and 0.8 pm diameter
is indicated by the trend shown by each system in this size range.
Resistivity Measurements
.In situ resistivity measurements were obtained at the main
inlet of Unit 3 and downstream from the air preheater. The results
from these measurements are presented in Table 10. Resistivity
data were scheduled to be taken during the second week of Phase II
downstream from the air preheater. However, these data were not
taken until August 21-23 due to the plant outage. The data ob-
tained at this location with the in situ probe are of questionable
value because of the limited amount of dust which could be
collected by the probe from the relatively low dust loadings which
existed downstream from the precipitator and air heater. After
operating for several hours, dust layers of only 0.015 and 0.02 cm
thickness were collected.
Laboratory resistivity measurements were conducted on four
ash samples obtained during the 'test program. These data are
presented in Figures 16, 17, 18, and 19, along with predicted
resistivities. Figure 18 also contains the high temperature
in situ data obtained during approximately the same time period.
The 355°C data were taken with an environment of dry nitrogen only
while the data taken at 154°C and 112°C were taken in the environ-
ment indicated in each figure. Each of the laboratory measurement
resistivity data points were extrapolated to an electric field
stress of 10 kV/cm to agree with the electric field used in the
resistivity predictions.
The predicted resistivity, using the method in EPA Report
EPA 650/2-74-074 is referred to as Method 1, whereas the predicted
resistivity referred to as Method 2 is a result of ongoing research
at Southern Research Institute sponsored by the Environmental
Protection Agency. The predicted data from Method 1 is for a
porosity of 50% and differs slightly from Method 2 due to the
additional research and sophistication of the prediction methods.
The predicted data (Method 2) and laboratory measured data at
112°C differ since the data used to develop the predictive
technique were obtained at 112°C after a long time exposure to
the environment (^5 hrs) and the laboratory data were taken as
soon as the ash and environment equilibrated (20 minutes).
Figure 20 contains predicted resistivity (Method 2) using an
analysis of coal ash from another coal source which has been used
at Navajo (Utah coal), but which was not in use during the EPA-
sponsored test series. These data are included to indicate the
40
-------
TABLE 10. IN SITU RESISTIVITY DATA, NAVAJO GENERATING
STATION
Date
7/21/77
7/22/77
7/22/77
7/22/77
8/21/77*
8/22-23/77*
Temperature ° C
346. 7
352.2
348.9
353.3
152.2
13.4.. 4
Resistivity,
ohm-cm
1.7xl09
3.9x109
9.5xl09
3.6x109
3.8xl012
9.0xl012
Location
Main Inlet
Main Inlet
Main Inlet
Main Inlet
Stack Inlet
Stack Inlet
*Questionable because of small layer (0.2 mm) in probe.
41
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Figure 16. Resistivity vs. temperature, 7/15-16/77
42
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108
107
1000/T(°K) —-
3.2
40
103
3.0
60
141
2.8
84
183
Z6
112
233
Z4
144
291
Z2
182
359
ZO
227
441
1.8
283
541
1.6
352
666
1.4
441
826
1.2
560
1041
TEMPERATURE
Figure 17. Resistivity vs. temperature, 7/18-19/77.
43
-------
1012
10"
o
5
I
o
CO
c/j
t~
SYM
o
o
D
A
P
RE
NO.
3
3
3
3
•D
C
T
l\
<
NAME
Navajo Predicted
Unit 3, Chamber 8,
02:17, 7/21-22/77
„
/E
y
/
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r
i
i
r
i/i
/
I
(
/
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L
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1C
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9.6
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s
°2
4.3
0
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5
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S
N
X
1
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CO2
14.6
0
13
13
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ii
S02
425
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0
0
s
;i
i
^
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<1
0
0
_5
i
k
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v
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/ >
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kl
W
TH
E, kV/cm
10
10
10
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P
Jp
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k
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/
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—
109
10?
1000/T(°K)
40
3.0
60
141
2.8
84
183
2.6
112
233
2.4
144
291
2.2
182
359
2.0
227
441
1.8
283
541
1.6
352
666
1.4
441
826
1.2
560
1041
TEMPERATURE
Figure 18. Resistivity vs. temperature, 7/21/77-7/22-77.
44
-------
1012
x
O
H
>
109
108
107
-t—
1
4r
i
~T~
r~
-j-(-
--•
—
SYM
O
o
D
A
P
NO.
4
4
4
4
R
NAME
Navajo Predicted
Unit 3, Ash Silo,
8/2 - 3/77
II II
EDICTIVE
(
/\
:f
IV
r
I
f.
;
/
/
1ETHOD
L
\
^
2
<
"
*
H2O
9.6
0
10.1
9.4
;-
i
>.
°2
4.3
0
5
5
S
S
S
CO2
14.6
0
13
j3
^
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\
S02
425
0
0
0
i.
^
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I
i
i
VL
PREDICTIVE
\
\
S03
<1
0
0
LQ
\
\
- -\
£>
^
tf\
\l
c
\
E, kV/cm
10
10
10
10
\
\
0
\
METHOD
\
^
'
\-\
-
I
\
(
i
>
—
—
-
-
-t—
-
1000/T(°K)
°C
°F
— 3.2
— 40
-*103
3.0
60
141
2.8
84
183
Z6
112
233
2.4
144
291
2.2
182
359
2.0
227
441
1.8
283
541
1.6
352
666
1.4
441
826
1.2
560
1041
TEMPERATURE
Figure 19. Resistivity vs. temperature, 8/2-3/77.
45
-------
SYM
o
NO.
NAME
Utah Coal Predicted
H2O
9.6
°2
-
CO2
-
SO2
425
S03
0
E. kV/cm
10
1012
o
o
t io10
CO
CO
10s
108
1000/T(°K) —- 3
— PR
E
t
3
|
/
f
/
c
/
T
y
f
<
f
IVE
/
if
f
t
V
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t*
=•
*1
>
/
c
n«
«4
—
3
ID 2
\.
*»
>
>
>
y
S
V,
C
I
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y
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\
^
>
i
\
^
\-
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\
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c
-
N
\
\
~
\
}
V
\
-
0 2.8 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2
O 84 112 144 182 227 283 352 441 560
41 183 233 291 359 441 541 666 826 1041
TEMPERATURE
Figure 20. Resistivity vs. temperature, Utah Coal,
46
-------
range of dust resistivities which may be encountered at the Navajo
Generating Station; the ash analysis upon which Figure 20 is based
is provided in Table 11. Compositions for the other graphs are
given in Table 14.
The following conclusions have been derived from the
resistivity data:
© The measured and predicted laboratory and in situ data
at 350°C show reasonable agreement.
@ The resistivity was relatively constant during the test
series.
© The in situ and laboratory data at 130-150°C are in
disagreement by about two orders of magnitude. Because
of the difficulty in collecting a sample for in situ
measurements, the laboratory data are considered more
reliable.
The effects of these data on precipitator performance and pro-
jected design are discussed in a subsequent section.
Coal and Ash Analyses
Tables 12 and 13 present the proximate and ultimate analyses
obtained from coal samples collected during each day of testing
for Phase I and Phase II, respectively. Chemical analyses were
obtained for selected ash samples obtained during Phase I and
Phase II from the inlet hopper of Chamber #8 and Unit Three ash
silo. These analyses are presented in Table 14 and are the
data used for the indicated samples in Figures 16, 17, 18, and
19 in the resistivity prediction methods. Note that no samples
indicate a sodium oxide content in the low range.
Gas Composition Measurements
Gas composition determinations were made at the outlet of
Chamber 8 during Phase I using methods previously described.
During Phase II of the test program, data were obtained at the
main inlet and at the stack sampling locations. Simultaneous
Orsat determinations were conducted at these two locations during
Phase II for the purpose of determining in-leakage, as was
discussed in the section on mass train measurements. Gas compo-
sition data from the Phase I and Phase II analyses are presented
in Tables 15 and 16, respectively. The SOx determinations indi-
cate that SO3 concentrations were never above the detection limit
of ^0.5 ppm at either the inlet or outlet to the precipitator
or at the stack sampling location.
47
-------
TABLE 11. CHEMICAL ANALYSIS OF UTAH COAL ASH USED FOR
FIGURE 201
Compound %
Li20 0.01
Na20 0.47
K20 1.84
MgO 3.15
CaO 13.35
Fe203 4.30
A1203 16.46
Si02 52.64
Ti02 0.81
P205 0.11
SO3 0.67
1. Analysis provided by Salt River Project from Commercial
Testing and Engineering Company data.
48
-------
TABLE 12. COAL ANALYSES, PHASE I
VD
DATE
PROXIMATE ANALYSIS
As Received
% Moisture
% Ash
% Volatile
% Fixed Carbon
BTU
% Sulfur
Dry Basis
% Ash
% Volatile
% Fixed Carbon
BTU
% Sulfur
ULTIMATE ANALYSIS
As Received
% Carbon
% Hydrogen
% Nitrogen
% Chlorine
% Oxygen (diff.)
Dry
% Carbon
% Hydrogen
% Nitrogen
% Chlorine
% Oxygen (diff.)
7/13-14/77 7/14-15/77 7/15-16/77 7/16-17/77 7/18-19/77 7/19-20/77 7/20-21/77 7/21-22/77
10.38
9.01
35.27
45.34
11392
.73
10.05
39.36
50.59
12712
.82
12. 85
6. 75
38.11
42.29
10866
.47
7.74
43. 73
48.53
12468
.54
12.21
7.44
38.36
41.99
10903
.46
8.47
43.70
47.83
12420
.52
11.77
6.84
38.41
42.99
11091
.39
7.75
43. 53
48. 72
12570
.44
11.95
6.45
39.53
42.07
11106
.46
7.33
44.89
47.78
12614
.52
11.93
6.31
39.13
42.63
11176
.41
7.16
44.43
48.41
12689
.47
11.80
6.05
39.19
42.96
11199
.41
6.86
44.43
48.71
12698
.46
12.34
9.27
37.81
40.59
10630
.48
10.57
43.13
46 . 30
12126
.55
64.03
4. 30
0.27
0.13
11.15
71.45
4.80
0.30
0.14
12.44
61.87
4.35
0.83
0.02
12.86
70.99
4.99
0.95
0.02
14.77
62.08
4.62
1.02
.02
12.15
70.71
5.26
1.16
.03
13.85
62.9*
4.49
0.71
0.04
12.77
71.40
5.09
0.80
0.04
14.48
63.02
4.51
1.12
0.04
12.45
71.57
5.12
1.27
0.04
14.15
63.15
4.48
1.11
.08
12.53
71.70
5.09
1.26
.09
14.23
63. 78
4.37
1.08
0.07
12.44
72. 31
4.96
1.22
0.08
14.11
60.58
4.16
1.39
.05
11.73
69.11
4.74
1.58
.06
1 :i.39
-------
TABLE 13. COAL ANALYSES, PHASE II
DATE
PROXIMATE ANALYSIS
As Received
% Moisture
% Ash
% Volatile
% Fixed Carbon
BTU
% Sulfur
Dry Basis
% Ash
% Volatile
% Fixed Carbon
BTU
% Sulfur
ULTIMATE ANALYSIS
As Received
% Carbon
% Hydrogen
% Nitrogen
% Chlorine
% Oxygen (diff.)
Dry
% Carbon
% Hydrogen
% Nitrogen
% Chlorine
% Oxygen (diff.)
8/2-3/77 8/3-4/77 8/4-5/77
11.41
9.67
38.11
40.80
10750
.50
10.92
43.02
46.06
12134
.56
11.95
11.38
37.64
39.02
10383
.62
12.93
42.75
44.32
11792
.70
7.85
12.50
35.02
44.63
11162
.75
13.57
38.00
48.43
12113
.81
60.63
4.39
1.08
0.04
12.28
68.43
4.95
1.22
0.05
13.87
59.14
4.15
1.01
0.04
11.71
67.16
4.71
1.15
0.05
13.30
65.55
4.26
1.21
.18
7.70
71.13
4.62
1.31
.20
8.36
-------
TABLE 14. ASH ANALYSES, PHASE I AND. PHASE II
Navajo Unit #3 Ash Analyses1
Date
Sample obtained
From
Time
Li20
Na20
K20
MgO
CaO
Fe203
A1203
Si02
Ti02
P205
SO 3
LOI
Soluble S04=
7/13-14/77
Chamber 82
04:40
0.01
1.96
1.18
2.00
9.85
5.61
20 .2
54.4
0.90
0.51
0.79
0.66
0.59
7/13^14/77
Ash Silo
05:20
0.01
1.80
1.25
1.75
7.36
5.46
24.2
57.6
0.95
0.47
0.68
0.84
0.50
7/15-16/77
Chamber 8
04:20
0.01
1.68
1.37
2.00
7.85
5.91
23.8
58.2
1.00
0.43
0.51
0.41
0.56
7/15-16/77
Chamber 8
04:58
0.01
1.77
.1.34
1.95
8.24
6.03
22.3
57.0
0.95
0.57
0.60
0.43
0.49
7/18-19/77
Chamber 8
05:00
0.01
' 1.90
1.36
2.00
8.09
5.73
22.1
57.4
1.00;
0.39
0.66
0.58
0.54
1 Analyses obtained from ignited samples except Soluble SOi, .
2Ash samples from Chamber #8 were obtained from the inlet hopper, which
received ash from half of Chamber #8.
51
-------
Date
Sample obtained
From
Time
Li20
Na20
K20
MgO
CaO
Fe2O3
A1203
Si02
Ti02
P205
SO 3
LOI
Soluble S0i» =
TABLE 14
(Continued)
Navajo Unit #3 Ash Analyses1
7/18-19/77
Ash Silo
05:30
0.01
1.65
1.34
1.90
7.55
5.78
22.2
57.3
0.95
0.41
0.62
0.70
0.53
7/21-22/77
Chamber 8 2
02:17
0.01
1.42
1.05
1.85
6.73
5.05
25.5
56.3
1.00
0.31
0.71
2.62
0.53
7/21-22/77
Ash Silo
02:40
0.01
1.61
1.20
1.90
7.93
5.57
22.0
58.0
0.95
0.33
0.69
1.14
0.53
8/2-3/77
Ash Silo
AM
0.01
2.20
1.27
1.70
7.12
5.25
20.1
56.9
0.95
0.50
0.68
1.14
0.53
8/3-4/77
Ash Silo
AM
0.01
1.80
1.38
1.65
6.25
5.34
20.8
60.2
1.00
0.34
0.58
1.62
0.44
8/4-5/77
Ash Silo
04:40
0.01
1.84
1.83
1.65
5.51
5.68
20.8
61.5
1.00
0.32
0.56
0.78
0.45
'Analyses obtained from ignited samples except Soluble SOt .
2Ash samples from Chamber #8 were obtained from the inlet hopper which
received ash from half of Chamber #8.
52
-------
Table 15
Date
7/11-12/77
7/12-13/77
7/13-14/77
7/14-15/77
7/15-16/77
7/16-17/77
7/18-19/77
Navajo Generating Station
Unit #3 Outlet of Chamber #8
Gas Analyses
Phase I
Time
03:30
23:00-23:30
00:00-01:00
01:00-02:00
02:00-03:00
03:00-04:00
04:00-04:30
05:00
22:30-23:00
23:00-00:30
00:30-01:30
01:30-03:00
03:00-04:00
04:30-05:00
22:30-
23:00-
01:00-
02:00-
03:00-
05:00-
22:30-
23:30-
01:00-
02:00-
03:30-
22:30-
23:30-
00:00-
01:00-
02:00-
03:30-
04:30-
22:00-
23:00-
01:00-
02:00-
03:00-
05:00-
05:30-
-23:00
-00:30
-02:00
• 03:00
•04:30
-05:30
-23:00
•01:00
-02:00
•03:30
•05:00
05:00
•23:00
•00:00
•01:00
•02:00
•03:30
•04:30
•05:00
•23:00
•01:00
•02:00
•03:00
•04:30
•05:30
•06:15
Volume, %
CO 2
02
15.2 5.0
15.2 4.6
15.0 4.2
15.2 4.5
H20
9.4
14.8 4.4 9.7
9.7
8.7
8.8
15.0 5.2
14.8 4.2 9.4
14.8 4.6
14.6 4.5 9.3
15.1 4.3 9.9
9.9
9.6
14.4 5.2 9.9
15.1 4.5 9.6
ppm,
S02
405
415
405
400
405
430
415
435
460
450
460
455
465
465
460
400
380
390
390
410
425
430
425
v/v
SO 3
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0. 5
<0.5
<0. 5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
<0.5
14.6 4.8 10.2
415
<0.5
53
-------
Table 15(Con1t)
Volume, % ppm, v/v
Date Time CO 2 0_2_ H20 S02 S03
7/19-20/77 22:00-23:00 14.8 4.4
23:00-00:00 9.7
00:00-01:00 420 <0.5
01:00-02:00 400 <0.5
02:00-03:30 400 <0.5
03:30-04:00 15.0 4.2 9.4 420 <0.5
7/20-21/77 22:00-23:00 14.3 5.3 9.8
23:00-01:00 420 <0.5
01:00-02:00 430 <0.5
02:00-03:00 420 <0.5
03:00-04:00 430 <0.5
04:00-04:30 9.6
7/21-22/77 22:00-22:30 15.3 4.1 10.2
22:30-00:00 430 <0.5
00:00-01:00 490 <0.5
54
-------
Table 16
Navajo Generating Station
Unit #3
.Gas Analyses
Phase II
8/1-2/77 Stack Gas Analyses
Volume/ %
Time CO 2 Pa
01:00-01:30 12.8 5.8
03:30 8.7
8/2-3/77 Main Inlet Orsat Traverse
Main Inlet A Side
Volume, %
Port f Time CO2 02
1 22:45 15.9 4.7
2 21:30 14.9 4.2
3 22:00 15.3 4.5
4 23:15 15.5 4.1
5 03:35 14.4 4.4
6 03:45 14.8 4.4
7 04:00 14.7 4.9
8 23:30 15.1 4.3
9 23:45 14.9 4.2
10 00:15 14.7 4.1
11 00:30 14.2 4.1
12 02:00 14.7 5.0
13 02:15 14.9 5.0
14 02:30 15.4 4.3
15 02:40 15.4 4.6
16 02:55 15.6 4.2
Main Inlet B Side
17 03:00 15.0 4.8
18 02:45 14.7 5.1
19 02:40 14.9 4.9
20 02:30 14.4 4.8
21 02:20 15.0 4.7
22 02:05 14.9 4.7.
23 00:50 ;14.3 4.1
24 00:35 14.2 4.2
25 00:2^ 14.4 4.4
26
27 23:50 14. .9 4.3
.28 23:35 15.0 4.4
29 23:20 15.0 4.0
30 22:55 14.. 6 4.7
31 22:30 14.6 4.8
32 22:10 15.2 4.2
55
-------
Table 16 (Cont'd)
Stack Gas Analyses
Volume, % ppm, v/v
Time C02 02 H20 S02 S03
03:15-03:30 14.1 5.7 8.6
03:30-04:15 400 <0.5
8/3-4/77 Simultaneous Main Inlet and Stack Orsats
Inlet Inlet Stack
Port # Time C02 02 C02 02
1 22:20 15.0 3.6 14.7 5.6
3 23:40 16.0 3.6 15.4 5.2
9 22:50 15.3 3.5 14.8 5.6
13 23:05 15.4 3.2 15.1 5.7
16 23:20 15.5 4.1 15.1 5.6
17 00:55 16.0 3.0 14.2 5.4
21 01:00 15.8 3.5 14.5 5.3
25 01:10 15.8 3.6 14.2 5.4
29 01:20 16.0 4.7 14.5 5.0
32 01:35 15.9 3.0 14.1 5.4
avg. 15.7 3.6 14.7 5.4
Stack Gas Analyses
Volume, % ppm/v/v
Time H20 S02 SO;
02:45 9.5
03:00-03:30 415 <0.5
03:30-04:00 445 <0.5
8/4-5/77 Simultaneous Main Inlet and Stack Orsats
Inlet Stack
Port # Time C02 02 C02 02
1 21:50 14.0 4.6 13.8 5.7
5 22:13 15.1 3.9 14.1 5.6
8 22:20 15.4 4.6 13.8 5.7
13 22:35 15.6 4.2 14.0 5.8
16 22:45 14.8 4.6 14.2 5.7
17 01:25 15.4 3.8 13.7 5.5
20 01:15 15.2 4.3 13.8 6.0
24 01:00 14.8 4.2 14.0 5.9
28 00:53 14.9 3.6 14.2 5.4
32 00:45 15.8 4.1 14.1 5.7
avg. 15.1 4.2 14.0 5.7
56
-------
Table 16 (Cont'd)
Stack Gas Analyses
Volume, % ppmyv/v
Time H20 S02 SO 3
03:00 8.9
03:30-04:00 500 <0.5
04:00-04:30 490 <0.5
57
-------
Voltage Current Measurements
The voltage-current characteristics of the precipitator were
monitored during the test program as follows:
o Voltage divider resistor assemblies were attached to
the high voltage bus-bars feeding Chambers 7 and 8
during Phase I. Corrected secondary voltages and
voltage waveform photos from an oscilloscope were
obtained.
o Voltage-current curves were obtained for each electrical
field of Chamber 7 and 8 during Phase I.
o Secondary and primary voltages and currents were obtained
from panel meter readings for Chambers 7 and 8 during
Phase I, and from all power supplies on the Unit 3
precipitator during Phase II.
Table 17 contains the average electrical operating parameters
for Chambers 7 and 8 during each test period of Phase I. Table
18 contains panel meter readings and corrected secondary voltages
for the voltage-current curves obtained on July 13, 1977. These
data are plotted in Figure 21. The remainder of the voltage-
current curves and the meter readings obtained during Phase I
for each transformer rectifier set are presented in Appendix 3.
The data recorded from all transformer-rectifier control panels
during Phase II are also given in the Appendix. These data are
discussed further in the theoretical analysis section.
Elemental Composition as a Function of Particle Diameter
Due to the elevated sampling temperatures, it was not
possible to use the substrates developed by Ensor10 for obtain-
ing size-classified samples from impactor stages for subsequent
analysis by an ion-excited x-ray technique (IXA). Greased
impactor substrates exhibit unacceptable weight losses at 350°C,
and therefore only conditioned glass fiber material was suitable
as a substrate. Unfortunately, these materials provide an
unacceptable background for the IXA method, and it was therefore
necessary to use a five-stage series cyclone assembly for ob-
taining size fractionated samples.
The cyclone assembly was operated at single points at the
inlet and outlet of Chamber 8 (Phase I) and at the main inlet
location (Phase II). Calculated cut points and pertinent oper-
ating data for the cyclones are presented in Table 19. Note that
it was necessary to operate at the precipitator outlet for almost
47 hours to obtain approximately 40 mg of sample in cyclone V.
Comparisons between differential mass distributions obtained with
the cyclone assembly and the impactor traverses are given in
Figures 22-24. The lack of agreement may be due in part to
58
-------
Table 17
Ul
vo
Navajo Generating Station
Unit #3
Average Voltage and Current Meter Readings
TR#
7/12-13/77
H
G
F
E
D
C
7/13-14/77
H
G
F
E
D
C
7/12-15/77
H
G
F
E
D
C
7/15-16/77
H
G
F
E
D
C
Volts
194.0
198.5
200.0
182.5
175.4
170.0
178.2
178.7
195.0
180.6
176.2
170.0
185.8
195.0
201.6
192.5
177.1
175.0
192.5
198.1
202.5
188.1
180.0
176.6
Primary
Amps
103.5
123.2
179.5
179.0
250.0
253.2
69.7
76.8
156.6
180.0
245.0
249.2
71.6
92.5
169.5
193.9
252.1
251.6
85.6
105.6
181.8
195.6
246.0
255.6
Chambers 7 & 8
KV
30.8
27.8
23.8
24,
22,
21.2
Secondary
MA
353.1
521.2
978.7
1081.2
1125.6
1430.6
Corrected KV1
28.9
27.1
23.2
24.3
21.5
20.0
437.0
558.5
1030.5
1022.5
1139.5
1420.0
26.7
25.8
21.8
20.8
19.5
17.3
28.8
25.7
23.1
23.9
21.5
20.3
281.2
384.3
804.3
987.5
1156.2
1386.8
26.8
25.2
22.2
21.2
19.8
17.4
30.2
27.6
23.7
24.2
21.4
21.3
305.0
448.3
943.3
1066.7
1179.1
1640.0
27.5
26.1
22.3
20.9
19.0
18.0
27.9
25.9
22.5
21.1
19.9
17.8
Spark Rate,
sparks/min.
112
92
60
38
16
15
69
88
61
51
75
12
93
33
42
66
81
63
63
28
53
28
Obtained with voltage divider assembly.
-------
Table 17 (Con't)
TRI
7/16-17/77
H
G
F
E
D
C
7/18-19/77
H
G
F
E
D
C
7/19-20/77
H
G
F
E
D
C
7/20-21/77
H
G
F
E
D
C
7/21-22/77
H
G
F
E
D
C
Volts
190.0
182.8
200.0
185.0
180.7
175.0
194.7
183.0
196.5
180.0
171.0
172.9
195.8
189.1
200.0
189.5
180.0
170.0
a
195.0
209.0
202.0
186.7
176.0
177.3
a
192.5
203.0
205.0
182.5
175.0
180.0
Primary
Amps
80.7
77.8
172.5
197.8
252.5
254.2
101.5
75.0
169.0
168.5
219.5
251.8
100.0
147.5
177.5
200.0
253.6
250.0
88.3
147.0
185.0
196.7
228.0
250.0
65.0
123.0
185.0
177.5
245.0
250.0
KV
30.0
26.8
23.5
24.0
22.1
20.8
29.9
26.1
22.9
23.5
21.7
20.5
Secondary
MA Corrected KV
30.2
27.4
23.4
23.9
21.2
20.5
337.1
365.7
948.5
1102.8
1153.5
1417.0
417.0
391.0
892.0
1079.0
948.0
1433.0
30.0
26.8
23.1
23.0
21.5
20.3
411.6
636.6
1025.8
1100.0
1206.6
1417.5
353.0
727.0
1043.0
1116.0
1083.0
1400.0
31.1
27.8
23.8
24.5
22.0
21.2
260.0
620.0
1050.0
930.0
1060.0
1430.0
27.6
24.7
22.5
21.0
16.3
17.0
27.5
24.2
21.5
20.3
19.9
17.5
27.0
25.3
22.6
20.6
18.9
16.9
27.2
25.8
22.8
21.4
18.6
17.1
28.0
26.2
23.2
21.9
19.3
17.7
Spark Rate,
sparks/min.
109
39
50
35
61
20
78
82
43
33
40
25
75
125
70
25
45
125
60
33
160
40
40
320
80
160
60
30
a) Corrected KV calculated from ratio of meter to corrected KV data of 7/19-20/77
because voltage divider data not available for 7/20-22/77.
-------
TABLE 18
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/13/77, 'H1 Field
Primary
Voltage Current
V A
Spark Secondary
Rate Voltage Current
Sparks/
min
KV
MA
Corrected
Secondary
Voltage
KV
Current
Density
nA/
cm2
85
160
170
180
185
190
195
—
20
50
65
75
100
110
—
—
100
120
150
300
500
19
28.4
29.5
28.5
29
29
28.8
--
100
200
260
320
400
450
18.3
26.8
27.1
27.4
27.2
27.4
26.8
4.3
8.5
11.1
13.7
17.1
19.2
Chambers 7 & 8, 7/13/77, 'G1 Field
75
150
160
170
180
190
195
Chambers
105
135
150
154
165
170
180
185
190
195
200
—
20
40
70
80
100
120
7 & 8,
—
20
50
68
85
110
125
145
157
170
180
—
—
20
50
100
150
350
7/13/77,
—
—
—
--
—
—
—
—
—
50
450
18.7
25
25.5
26.5
27
26.5
26
'F' Field
19
21.4
22.1
22.2
22.3
22.4
22.6
22.4
22.5
23
23
100
200
300
400
500
600
20
100
200
300
400
500
600
700
800
900
1000
16.8
24.2
25.2
25.5
25.7
25.3
25.0
17.9
20.4
21.1
21.3
21.4
21.7
21.5
21.5
21.8
22.1
20.3
4.3
8.5
12.8
17.1
21.4
25.6
.9
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
61
-------
TABLE 18 (Con't)
Primary
Voltage Current
V A
Spark Secondary
Rate Voltage Current
Sparks/
min
KV
MA
Corrected
Secondary
Voltage
KV
Current
Density
nA/
cm2
Chambers 7 & 8, 7/13/77, 'E' Field
100
130
140
150
155
157
165
170
175
180
185
Chambers
105
134
140
148
150
160
164
168
172
175
180
Chambers
110
115
138
140
148
150
155
160
164
164
170
175
--
20
50
67
80
105
120
140
155
170
185
7 & 8,
— _
50
102
132
150
180
200
215
233
245
257
7 & 8,
—
55
90
110
138
155
180
200
220
234
252
262
—
—
—
—
—
—
—
—
20
30
125
7/13/77,
_
--
—
—
—
20
40
50
100
120
200
7/13/77,
—
—
—
—
—
--
—
—
—
—
—
—
20
23
23
23.5
23.5
24
24
23.8
23.8
24
23.5
'D' Field
19.5
20.5
20.8
20.9
21
21.3
21.4
21.5
21.5
22
22.4
'C1 Field
19
19.8
20
20
20
20
20
20
20
20
20.4
20.8
100
200
300
400
500
600
700
800
900
1000
100
250
400
500
650
800
900
1000
1100
1200
17.5
20,
20,
20.6
20.7
20.8
20.8
20.9
20.8
21.1
21.0
17.7
18.7
18.9
1
1
19
19
19.2
19
19
19
19
1
3
5
7
19.8
19
19.8
20
20
20
20
20
20
20
20
20.4
20.8
100
250
400
500
650
750
900
1000
1150
1250
1400
1500
17.2
17.4
17.3
17.2
17.1
16.9
16.9
16.9
17.1
17.2
17.4
18.0
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
4.3
10.7
17.1
21.4
27.8
34.2
38.4
42.7
47.0
51.3
4.3
10.7
17.1
21.4
27.8
32.0
38.4
42.7
49.1
53.4
59.8
64.1
62
-------
CM
O
c
V)
2
HI
Q
H
CURREIV
70.0
65.0
60.0
55.0
50.0
45.0
40.0
35.0
30.0
25.0
20.0
15.0
10.0
5.0
—
0 c
^
—
y"
h o s
- x S
O ACO*^
O A DO
~ A DO
0
- DD
O A
_ DO
O A DO
O A DO
DD
^ DD
"~ O A OD
Q 6 12 18
VOLTAGE, kV
O H FIELD
V G FIELD
0 F FIELD
D E FIELD
A D FIELD
O C FIELD
9 OPERATING POINT
E
^^ I
«• j«G
^7 ^^^
^7 •"
v 0
v<>
0
v O
\7 O
1 I 1 1 1
24 30 3e
Figure 21. Voltage-current curves for Chamber 7 and 8,
July 12-13, 1977.
63
-------
TABLE 19. CYCLONE ASSEMBLY OPERATING PARAMETERS
Run #
Location
Date
Cyclone
I
II
III
IV
V
F
CYC 3
Chamber #8, Inlet
7/14-15/77
Wt.,g D50,ym
CYC 5
Chamber #8, Outlet
7/18-19/77
Wt.,g D5 o,ym
12.6246
3.4288
1.2157
0.7791
0.1002
0.1179
7.2
3.5
2.3
1.2
0.5
0.3762
0.2016
0.2046
0.2293
0.0421
0.0336
6.8
3.2
2.1
0.96
0.46
CYC 7
Main Inlet
8/3-4/77
Wt.,g D5 o /
5.7684
9.1620
3.2084
1.4835
0.5308
0.1232
6.8
3.2
2.1
0.96
0.45
Ambient Pressure, "Hg 25.57
Stack Pressure, "Hg 24.76
Ambient Temperature,°F 85
Ambient Temperature,°C 29.4
Stack Temperature,°F 685
Stack Temperature,°C 362.8
Flowrate, ACFM 1.068
Flowrate, Am3/min 0.0302
Sample duration, minutes 270
Maximum Particle
Diameter, ym 32
Moisture,% 9.2
25.44
24.76
85
29.4
630
323.2
1.107
0.0314
2795
32
9.5
25.75
24.76
100
37.8
700
371.1
1.201
0.0340
258
107
9.5
-------
id5-
id3-
101-
10°-
I
o
^ IMPACTORS
O CYCLONE
10°
PARTICLE DIAMETER (MICHDMETER5)
Figure 22.
dM/dlogD vs. peirticle diameter for all impactors
operated at the main inlet of the #3 precipitator
and cyclone run 17.
65
-------
10P-
a 2
' 0
0
SS S
B
I*
10
21
0
a IMPACTORS
O CYCLONE
-\—h-M-H+H 1—i i i mil 1—i ) i iiiH
10'1 10° 101
PARTICLE DIAMETER (MICROMETERS)
Figure 23.
dM/dlogD vs. particle diameter for all impactor's
operated at the inlet of chamber #8 and cyclone run #3
66
-------
4LY1HU137
EX01IIE HffiE IS IHffl <5 IfflHEfi
JJUr-
S iQ1-
g ;
s^
§ '•
a
a •:
•irr1-
0
i *j° p* Iijj
I XH s
: I
; I
©
Q
A IMPACTORS
O CYCLONE
m
1 1 1 1 IH1-1 1 1 — 1 I MlM i Jl 1 — 1 1 1 1 1 1.J
icr1
PARTICLE DIAMETER (MICROMETERS)
Figure 24.
dM/dlogD vs. particle diameter for all impactors
operated at the outlet of chamber #8 and cyclone run #5
67
-------
differences in integration time and mass concentration gradients,
but it is also possible that the theoretical extrapolation of
ambient temperature calibration data for both systems introduce
significant sizing errors at 350°C. It appears that better
agreement was obtained at the inlet (Brink vs. cyclone) than at
the outlet (Andersen vs. cyclone).
Table 20 contains the mass concentrations per cyclone which
were used in the calculation of elemental concentrations and ele-
mental penetrations. Table 21 presents the data obtained by
Crocker Nuclear Laboratories as parts per million by weight from
samples of the collected material in each cyclone. The back-up
filter, since it consisted of glass fiber, was again unsuitable
for this type of analysis. Table 22 gives elemental penetration
as a function of particle diameter across Chamber 8, and Figure 25
gives penetration as a function of particle diameter for selected
elements and for the total mass collected with the cyclones.
These data indicate the trace elements generally follow the mass
collection curve. It should be noted that the penetrations are
calculated from sequential single point samples, and are there-
fore qualified as "apparent" penetrations.
Enrichment ratios were computed as suggested by Ensor,1l
except that all concentrations were normalized to iron. These
data are presented in Appendix 4, along with elemental concen-
trations in units of mass per volume of dry standard flue gas as
a function of particle diameter.
Summary of Results from Previous Tests
As stated previously, Southern Research Institute conducted
field tests on Chamber 8 of Unit 3 under the sponsorship of
EPRI and the Salt River Project prior to the performance of the
EPA test series. This section will summarize the results from
this work as it relates to the objectives of the EPA project.
The objectives of the EPRI-SRP series were:
(1) Examine the effect of gas velocity distribution on
precipitator performance.
(2) Conduct a rapper optimization study by changing rapping
system activation time intervals.
(3) Determine whether emissions are increased as a result
of hopper in-leakage.
(4) Determine the contribution of electrode rapping to
particulate emission from the precipitator.
68
-------
TABLE 20. MASS CONCENTRATION AND EFFICIENCY FROM CYCLONE
ASSEMBLY (PHASE I)
Cyclone
Average
1
2
3
4
5
7.0
3.35
2.2
1.08
0.48
Filter
Mass Concentration, mg/DSCM
Inlet(Run 3) Outlet(Run 5)
TOTAL
4.45xl03
1.21xl03
4.29xl02
2.75xl02
3.53X101
4.16X101
6.44xl03
11.8
6.31
6.40
7.17
1.32
1.05
34.05
Efficiency
99.73
99.48
98.51
97.39
96.26
97.48
99.47
69
-------
TABLE 21
CYCLONE RUN #3 CHAMBER #8, INLET 7/14-15/77
CONCENTRATION OF ELEMENTS LISTED IN PARTS PER MILLION BY WEIGHT
Cyclone 8
1
2
3
4
5
Ca
Zn
66.8
177.3
267.9
364.0
385.3
Ti
Ba
Cr
Mn
As
Ca
Pb
Br
Rb
Sr
12.5
20.8
77.6
37.0
45.5
18.7
61.3
111.2
114.4
188.4
5.0*
14.0*
20.0*
27.0*
57.0*
CYCLONE RUN #5 CHAMBER #8, OUTLET 7/18-19/77
Ti Ba V Cr
Zr
48.1
66.6
70.8
52.8
68.8
1429.9
1775.4
1704.1
1443.9
2211.7
157.3
152.3
128.8
142.6
145.0*
Fe
Mn
Mo
25.0*
43.6
92.0*
334.6
261.0*
Fe
Cu
4728.4
8193.7
7940.3
7810.0
9598.3
34145.6
50201.5
50712.3
45960.6
58729.0
5561.5
7494.2
7350.4
6928.7
10722.9
212.0*
486.0*
650.0*
864.0*
1821.0*
613.8
1142.4
1461.3
1512.4
3151.5
40.0*
88.0*
114.0*
691.2
307.0*
77.8
76.0*
100.0*
134.0*
427.1
28767.0
39505.5
40076.4
38931.5
47743.1
49.3
83.1
84.6
95.3
207.8
Cu
5952.3
6157.0
6786.6
7116.0
6039.3
49867.9
50105.6
47390.7
48112.2
47250.7
6761.8
6770.0
6726.7
7525.1
7377.8
504.0*
539.0*
697.0*
892.0*
1084.0*
1443.1
1468.3
1586.9
1971.4
2566.9
88.0*
93.0*
115.0*
203.6
176.0*
76.0*
81.0*
101.0*
129.0*
158.0*
33208.5
32578.9
32709.6
35511.3
31582.0
79.5
59.9
113.5
102.6
116.5
Zn
194.0
202.5
232.4
351.8
372.3
Zn
53.0
83.9
150.7
220.2
240.6
As
Pb
Br
Sr
Zr
9.0*
10.0*
30.3
32.0
51.6
114.5
117.3
99.7
117.3
113.3
14.0*
16.0*
22.0*
28.0*
36.0*
43.8
42.8
51.8
56.3
32.1
1732.8
1712.6
1558.6
1619.0
1642.5
110.6
98.7
97.6
112.0
91.0*
Ca
CYCLONE RUN 87 MAIN INLET 8/3-4/77
Ti Ba V
Cr
Mn
As
11.5
26.5
22.4
24.7
48.0
Pb
Br
Rb
Sr
Zr
25.2
23.3
61.3
88.5
92.4
5.0*
9.0*
12.0*
19.0*
20.0*
65.2
87.0
90.2
87.1
104.8
1305.6
1432.6
1515.3
1420.1
1534.1
204.7
182.3
147.6
129.5
119.7
Mo
66.0*
75.0*
100.0*
131.0*
164.0*
Fe
Mo
24.0*
40.0*
53.0*
85.0*
90.0*
Cu
6073.9
8209.9
9474.1
10166.6
10064.2
25109.3
29333.3
32191.6
33178.7
30901.4
5463.5
6210.3
7180.4
7043.5
7542.7
206.0*
325.0*
424.0*
628.0*
670.0*
633.3
772.3
827.5
1229.5
1278.1
39.0*
59.0*
77.0*
111.0*
120.0*
106.2
134.6
129.1
183.7
190.5
30249.1
33791.8
36951.3
37301.9
40185.6
41.8
53.2
69.7
78.9
76.6
*Denotes upper limit of element not found.
-------
TABLE 22
ELEMENTAL PENETRATION ACROSS CHAMBER #8
Avg. D5o Cyclone 8
7.00
3.35
20
08
0.48
7.00
3.35
2.20
1.08
0.48
1
2
3
4
5
Zn
Ca
Ti
Ba
Cr
Mn
Fe
As
Pb
Br
Rb
Sr
Zr
Mo
0.0077
0.0060
0.0130
0.0252
0.0360
0.0019*
0.0025*
0.0058
0.0226
0.0423
0.0162
0.0100
0.0134
0.0268
0.0224
0.0074*
0.0060*
0.0164*
0.0271*
0.0235*
0.0024
0.0034
0.0109
0.0278
0.0174
0.0032
0.0050
0.0137
0.0293
0.0277
0.0019
0.0034
0.0113
0.0205
0.0234*
0.0070*
0.0090*
0.0162*
0.0102*
0.0234*
Cu
0.0033
0.0039
0.0128
0.0238
0.0235
0.0039
0.0052
0.0140
0.0273
0.0300
0.0032
0.0047
0.0137
0.0284
0.0257
0.0063*
0.0058*
0.0160*
0.0270*
0.0222*
0.0062
0.0067
0.0162
0.0340
0.0304
0.0058*
0.0055*
0.0151*
0.0077
0.0214*
0.0026*
0.0056*
0.0151*
0.0251*
0.0138*
0.0031
0.0043
0.0122
0.0238
0.0247
0.0043
0.0038
0.0200
0.0281
0.0209
*Denotes upper limit of element not found.
-------
90r
s?
u
o
O
LU
O
o
O_
Q.
I I I I I I I I
99.9
0.1
I I I I I L
I I I I I I I
O -
I I I I I I I Innm
0.1
<
cc
0.01 £
LU
CC
a.
a.
1.0
PARTICLE DIAMETER,/jm
Figure 25. Apparent elemental collection efficiency.
(Chamber 8)
10.0
72
-------
The principal conclusions derived from the test results
were:
(1) The fraction of emissions attributable to rapping was
decreased by an increase in the outlet field rapping
intervals.
(2) A reduction in the normalized standard deviation of the
gas velocity distribution from 44% to 17% (at the inlet)
did not appear to significantly improve collection
efficiency under the conditions of the test.
(3) The two principal causes of the lower than desired
performance of the unit are the relatively low operating
voltages and the relatively low values of specific
collecting area.
(4) The pressurization and depressurization of the ash
removal system did not cause a measurable change in
emissions from chamber 8.
(5) Half-load operation can have serious detrimental effects
on the performance of the precipitator.
These conclusions will be discussed in more detail in the
subsequent section concerning theoretical analysis.
The measurement of particulate emissions resulting from
electrode rapping were conducted by (1) using an extractive
sampling system with a size selective diluter and an optical
particle counter, (2) traversing the duct with impactor and mass
train sampling systems using an alternating sampling plan in
which rappers were energized and subsequently de-energized.
Figure 26 contains data for concentration of 6-12 ym
diameter particles vs time obtained at the outlet of chamber 8
with the extractive sampling system. Each data point on the
graph represents a 10-minute integration time. Points A and C
correspond with the inlet and outlet field raps, respectively.
The data points labeled C will necessarily include inlet and
outlet field raps due to the 10-minute integration time. The
center fields and wire rappers are not distinguishable on this
graph from the background data, but were noticeable when they
occurred. Note that the outlet fields (C and D) exhibit two
large rapping puffs, suggesting layer buildup until rapping
forces were sufficient to dislodge the layer.
Figure 27 contains the fractional efficiency data obtained
with the EAA and impactor systems with and without electrode
rapping. It is apparent that the most pronounced effect of rap-
ping occurs for particle diameters of 2.0 ym and larger. The
total mass attributed to rapping, expressed as a fraction of
73
-------
LLJ
_l
o
I-
cc
o
X
C , C AND D FIELDS RAPPING
A . G AND H FIELDS RAPPING
9:00 10:00 11:00 12:00 1:00
TIME, hours
2:00
3:00
4:00
3698-007
Figure 26.
Particles/Minute vs. time for 6-12 micron
particles, February 1, 1977.
74
-------
PEhCTRATIOM-EFFICIENCY
a
a
LJ
s
u
a
u
CL
lO2^
101::
lO'1^
H
OPEN SYMBOLS - NO RAP
CLOSED SYMBOLS - RAP
&AULTRAFINE
© O IMPACTOR
a.
< O
cc z
NO RAP
© O
JJ
T OoO
:r90oO
U
M
U
M
U_
LJ
u
QL
UJ
CL
8.99
I—J-H+HH 1 I i lif!i{ 1 1 8 Illlll 1 I HUH
1CTS 1CT1 10° 101 1
PARTICLE DIAMETER (MICROMETERS)
Figure 27. Ultrafine and impactor fractional efficiencies
for Rap-No Rap test.
Navajo
75
-------
outlet emissions, was estimated to range between 44 and 63% based
on the impactor and mass train traverses. The performance of
chamber 8 was somewhat higher during the EPA-sponsored series
(99.2 vs 98.98%), and this is reflected in the fractional
efficiency data of Figures 9 and 27.
THEORETICAL ANALYSIS
Voltage-Current Relationships
The collection rate of particulate matter in an electro-
static precipitator is a function of the applied voltage and the
resulting corona current. Therefore, an understanding of the
factors which limit particle collection rates under a given set
of conditions requires an analysis of the relationship between
the applied voltage and corona current.
For wire plate geometry, the relationship between applied
voltage and the electric field distribution in the space between
wire and plate for a given value of current may be obtained by
a numerical solution of Poisson's equation and the continuity
equation at steady state conditions. The method employed for
this calculation is a numerical technique introduced by Leutert
and Bohlen12 in which the applicable partial differential
equations are solved simultaneously under boundary conditions for
wire-plate geometry. The equations which must be solved are
written in discrete form in two dimensions as
2 2
AV AV -p
Ax2 + Ay2 = —
and
2 AV A£ AV Ap ( }
p ° Ax Ax Ay Ay ^ '
where
p = space charge, coul/m3;
y = distance parallel to gas flow from wire to wire, m;
x = distance perpendicular to gas flow from wire to plate, m;
e0 - permittivity of free space, coul2/(N-m2); and
V = potential, volts.
The numerical procedure consists of an iteration technique
in which the space charge density at the wire is adjusted until
all the boundary conditions, which include the applied voltage
and the corona current, are satisfied. For each choice of space
charge density at the wire, the procedure iterates on a grid of
electric potential and space charge density until convergence is
obtained. The program then checks to determine whether the
boundary condition on the average current density at the plate is
met by using the expression
76
-------
j = (be J^ PpiEpi)/N (3)
where
j = average current density at the plate (A/m2);
be = effective charge carrier mobility (m2/V-sec);
Ppi = space charge densities for points on the plate (coul/m3);
Epi = electric field strengths for points on the plate, V; and
N = number of grid points in the direction of gas flow.
If the boundary condition on the average current density at
the plate is not met, then the space charge density at the wire
is adjusted and the iteration procedure is repeated.
The foregoing procedure provides a method of obtaining
electric field distribution for instances in which voltage and
current are known parameters, and is used in the calculation of
theoretically predicted collection efficiencies.13 McDonald et
al1" have described a technique, based on the same mathematical
relationships, which may be used to generate a voltage-current
characteristic for wire plate geometry. The results obtained
from this technique are a function of the electrode geometry and
the value used for effective charge carrier mobility. Poisson's
equation and the continuity equation are solved as previously
described for a series of points on the voltage-current curve,
but with a different set of boundary conditions imposed. The
space charge density in the region of ionization near the dis-
charge electrode is calculated from an arbitrarily chosen value
of average current density at the plate. The space charge
density near the wire and the average current density at the
plate provide boundary conditions which are held fixed, while
the voltage at the wire is adjusted until solutions are found to
equations 1 and 2 which satisfy all the,boundary conditions.
McDonald's procedure has been used to analyze the voltage-
current relationships obtained during the test series at the
Navajo Generating Station. Figure 28 contains voltage-current
curves from a computer program used to implement the method.
These results are based on the existing wire diameter of 0.268 cm
(0.1055 in), although, as will be shown later, the results are
quite sensitive to wire diameter variations which could result
from dust deposits. The curves indicate the importance of charge
carrier mobility in the prediction of electrical operating
parameters. The mobility values shown in Figure 28 are repre-
sentative of a range which would be expected if voltage-current
curves were obtained at temperatures ranging from ambient to
^350°C and with gases consisting of atmospheric air at ambient
temperature and typical flue gas components at 350°C.
77
-------
80.0
75.0
70.0
65.0
60.0
55.0
50.0
CM 45.0
u
c 40.0
H
2 35.0
LU
DC
DC
30.0
25.0
20.0
15.0
10.0
5.0
0.0
VOLTAGE-CURRENT CURVES
©o
O be = 2 cm2/VOLT-SEC
A be = 10 cm2/VOLT-SEC
D be = 15 cm2/VOLT-SEC
O be = 20 cm2/VOLT-SEC
10
20
30
VOLTAGE, kV
40
50
60
Figure 28
Theoretical voltage-current relationships for
wire diameter of 0.268 cm (0.1055 in), wire to
plate spacing of 11.45 cm (4.5 in), and wire to
wire spacing of 22.9 cm (9.0 in).
78
-------
Recent measurements with an apparatus designed to determine
charge carrier mobility indicate be values of 15-20 cm2/volt-sec
may be encountered at the operating conditions of the Navajo
Station precipitator.*5 .These data also indicate that (1) the
gas charge carrier mobilities may be sensitive to small compo-
sition changes, and (2) extrapolation of reduced mobility values
for flue gas using ideal gas law temperature and pressure ratios
to operating conditions does not give a result in agreement with
the measured values under these conditions. For example,
available data indicate that 3.0 cm2/volt-sec is an appropriate
value for reduced effective mobility (0°C, 1 atm) in a typical
flue gas. An ideal gas law type of extrapolation to the precipi-
tator environment at Navajo results in a be value of about 8.2
cm2/volt-sec, or approximately one-half the value indicated by
the ir\ situ measurement.
Since the last field of the precipitator will experience the
lowest dust concentration and associated particulate space
charge, an evaluation of the theoretical voltage-current
characteristics can best be performed through a comparison of the
theoretical curves with actual data from a typical outlet field.
Procedures have been devised for estimating the effects of
particulate space charge on voltage-current characteristics, but
this issue constitutes an additional complication which need not
be considered in this discussion. Figure 29 indicates that the
theoretically derived voltage-current curve closely simulates a
typical "C" field curve from chamber 8, which was obtained after
testing on July 15, 1977. The theoretical calculations were
based on the actual electrode geometry, an assumed "roughness
factor" for the discharge electrode of 0.9, and an effective
carrier ion mobility of 15 cm2/volt-sec.
The procedure for generating the V-I curve contains no
expressions which represent the influence that dust deposits on
the electrodes might have on voltage-current characteristics,
other than the "roughness factor" for the discharge electrode
which is related to dust deposits on the wire. Therefore, the
agreement between the theoretical and actual voltage-current
relationships shown in Figure 29 contains an inference that the
voltage-current relationships at Navajo are not influenced by
dust layer phenomena. However, the following observations
strongly indicate that dust deposits are influencing the
functional relationship between applied voltage and corona
current in a manner which is not adequately represented by
equations 1 and 2.
o The voltage-current relationships do not respond to
changes in electrode diameter in accordance with
theoretical predictions.
79
-------
70.0
60.0
50.0
CM
O
> 40.0
oo
UJ 30.0
cc
D
u
20.0
10.0
0.0
O THEORETICAL, be = 15 cm2/volt-sec
D EXPERIMENTAL, C FIELD, Ch 7 & 8
JULY 15, 1977
I
12 18
VOLTAGE, kV
24
30
Figure 29.
Comparison of theoretical (be = 15 cm2/volt-sec)
and experimental (C Field, Ch. 7 & 8, July 15, 1977)
voltage-current curve.
80
-------
© Photographs of voltage-current waveforms suggest a
back corona type of discharge at high current levels.
o There is some evidence of hysteresis in the V-I curves
from the outlet field.
o The V-I curves are influenced by electrode cleanliness.
o Precipitator performance is influenced by dust
resistivity changes in a range of resistivity values
below that which would be expected to limit performance.
Figure 30 compares theoretical and actual V-I curves for
various wire sizes. The data for C field of Chambers 1 and 2
were obtained after 0.457 cm (0.18 in) diameter wires had been
installed in an effort to improve operating voltages. Although
the voltage required for a given current does appear to have been
increased by the larger wires, the degree of increase is much
less than theoretically predicted. These data suggest that
factors other than discharge electrode geometry are limiting the
attainable voltages for given current levels.
Figure 31 illustrates voltage waveforms obtained from
C field of Chambers 7 and 8, at corona start, the "knee" of the
V-I curve, and at the maximum operating point under automatic
control. These waveforms illustrate that the voltage between
the discharge and collecting electrodes drops below the corona
onset voltage at high current densities, indicating that the
energy stored in the capacitance of the precipitator is being
drained by a discharge process which continues down to voltages
as low as approximately 10 kV. Normally, the discharge process
stops when the applied voltage drops to the corona onset value.
Electrical breakdown in the dust layers on the collecting
electrodes is a possible explanation.
Further evidence of dust layer effects is observed by a
comparison of V-I curves obtained from C field, Chambers 7 and 8.
Immediately following start-up from an outage during which the
chambers were washed and new wires were installed in the C field,
comparisons were made between the clean electrode curves and
those obtained after considerable operating time had elapsed.
Figure 32 illustrates the change in the voltage-current curves
from May to August of 1977. Although some of this change may be
due to changes in ash characteristics, a comparison with the data
from C field of Chambers 5 and 6, which were taken at the same
time, clearly shows the effect of electrode cleaning on the shape
of the voltage-current relationship.
The influence of dust resistivity changes on precipitator
performance was observed during a half-load test on Chamber 8
of unit 3. This test was conducted during the test series of
January 1977. As the precipitator operating temperature dropped
81
-------
CM
l-
LL
00
Ul
cc
cc
o
60
50
40
30
20
10
18
O C FIELD Ch 7-8
D C FIELD Ch 1-2
LARGE WIRES
METER READINGS
FROM 8/21/77
I
r
i
i
.268 cm
(.1055 in.)
I
.411 cm
(.162 in.)
I .PI
I
20
22
24 26
VOLTAGE, kV
28
I
.462 cm
(.182 in.)
65
54
43
CM
E
o
32
22
11
30
32
Figure 30. Theoretical and experimental voltage-current
relationships for various wire diameters.
82
-------
0
-1
-.2 CORONA START
-3
-4
Q
-1
-2
-3
MAXIMUM
AUTOMATIC
OPERATING POINT
KNEE OF CURVE
5 10 15 20 25 30 35 40 45
Figure 31. Voltage waveforms for C Field, Chambers 7 and 8.
83
-------
CM
E
0
c
»
>
-
2
LU
D
,
2
LU
DC
DC
0
ttU
75
70
65
60
55
50
45
40
35
30
25
20
15
10
5
1 1 1 1 1
A C FIELD, Ch 7-8 8/21/77 (SRI DATA)
- O C FIELD, Ch 5-6 MAY 1977 (NO CLEANING))
D C FIELD, Ch 7-8 MAY 1977 NEW WIRES, >
CLEAN PLATES ) W'P' DAIA
(ALL METER READINGS - UNCORRECTED) Q
^™ ^™
- -
D
A
0
— —
_ _
A o n
_ _
A
— —
A
D
— —
D 0
— —
A
D
O
- -
-DO
A
O
A
I I I I I
18 20 22 24 26 28 31
VOLTAGE, kV
Figure 32. Voltage-current relationships for C Fields,
Chambers 7 and 8 and Chambers 5 and 6.
84
-------
from 360 to 233°C, the TR sets exhibited heavy sparking, and the
operating points were much lower under automatic control at half-
load conditions than they were at 800 MW. The collection
efficiency dropped from 99.26 to 92.17%, even though the specific
collecting area of the precipitator was doubled as gas flow
decreased. The electrical operating characteristics suggest that
dust resistivity increased to the point that breakdown was
occurring in the deposited dust layer and that the resulting
sparking severely limited the performance of the unit. Labora-
tory resistivity data indicated that dust resistivity would
increase from 8x108 to 2x1010 ohm-cm due to the temperature drop
associated with half-load operation.
Figure 33 illustrates the effect of half-load operation on
the voltage-current curves and the operating points at Navajo
for the outlet fields. Also shown is a voltage-current curve
from another hot-side precipitator outlet field. "Plant 4" was
tested under another program sponsored by EPRI, and illustrates
that the steep V-I curves observed at Navajo are not always
experienced with hot-side operation. The collection efficiency
degradation observed with half-load operation at Navajo probably
could have been avoided with properly operating TR set controls,
but the test results are important in that they indicate a
sensitivity of precipitator operation to resistivity variations
in a region where no sensitivity was expected.
Model Projections
The preceding discussion indicates that the low operating
voltages observed at Navajo may result from a combination of high
effective mobilities for the charge carrying species of the gas
stream and an electrical discharge process which occurs in the
deposited dust layer and which persists at voltages below the
normal corona onset voltage. Comparison of actual precipitator
performance with projections of a mathematical model16 under
cold-side conditions where sparking and back corona were occur-
ring indicated, as would be expected, that the actual performance
was lower than the theoretical projection. This results from the
deleterious effects of a bipolar charging environment on particle
collection in a negative corona field.
Figure 34 contains comparisons between projections of the
mathematical model and field measurements of overall mass collec-
tion efficiency for Chamber 8 and for the entire precipitator.
The input data for the model included measured values of oper-
ating voltage and current levels, particle size distribution, gas
flow, and precipitator geometry. The comparison shows that the
model significantly underpredicts the measured overall mass
collection efficiency of Chamber 8, which was obtained with both
mass train and impactor sampling systems. The underprediction
suggests a fundamental difference between the apparent back
corona characteristics observed for Chamber 8 and those observed
85
-------
60
50
40
LL
a.
30
DC
oc
D
o
20
10
16
O PLANT 4
£ NAVAJO, 800MW
D NAVAJO, 400 MW
& OPERATING POINTS
& NAVAJO, 400 MW
O 150-400 SPM
O 200-300 SPM
D 25-75 SPM
a
NAVAJO, 800 MWA
I
18
20 22
VOLTAGE, kV
24
PLANT 4
26
65
54
45
32
CVJ
E
o
22
11
28
3698-005
Figure 33.
Outlet field voltage-current curves for Chambers 7 & 8
(Navajo) and another hot side precipitator installation,
06
-------
99.9
s?
> 99.5
o
z
UJ
O
p 99.0
o
LLJ
O
O
98
97
95
90
CHAMBER 8
MEASUREMENTS
ENTIRE UNIT
MEASUREMENT
150 200
29.5 39.4
250 300 350
49.2 59.1 68.9
SPECIFIC COLLECTING AREA
400
78.7
450 FT2/1QOO cfm)
88.6 m2/(m3/sec)
Figure 34. Measurements and model projections of collection efficiency
for hot-side operating parameters.
87
-------
for cold-side (150°C) operating conditions with high resistivity
dusts (^1x1012 ohm-cm). Particle charging by free electrons is
a possible cause for the underprediction, and current transport
by free electrons may be a factor in the high values of effective
mobility which are indicated by the in situ measurements.
Electron mobilities are of the order of 100 to 1000 times the value of
typical electronegative gas ion mobilities, and the mathematical
relationships for projecting particle charging rates are no
longer valid.
Given the large underprediction that results when the model
is applied with the measured operating parameters at Navajo, it
is necessary to adjust the input voltages (which, in effect,
scales the results to agree with the overall mass efficiency) in
order to use the particle size dependent relationships in the
model for estimating overall efficiency as a function of specific
collecting area. Line 3 in Figure 34 gives the model results
when the input voltages are increased 33%. Line 2 was obtained
with the same input data but with larger values of the parame-
ters used to represent nonideal effects due to the reduced
performance of the entire unit compared to that of Chamber 8.
The indicated requirement of specific collecting area for the
design efficiency of 99.5% is 78.7 m2/(m3/sec) or 400 ft2/1000
acfm. The recommended value of specific collecting area is
93.9 m2/(m3/sec) Or 477 ft2/1000 acfm, which contains a safety
margin of 19%. Line 4 was obtained using voltage and current
values measured with a hot-side precipitator collecting ash from
an Eastern coal. All other input parameters were obtained from
the Navajo test series on Chamber 8.
The collection efficiency relationship indicated by line 4
is what the model would predict in the absence of significant
dust layer effects or unusually high values of effective charge
carrier mobilities. This projection indicates that the de"sign
efficiency (99.5%) is theoretically attainable at the design
value of SCA if the expected electrical operating conditions
could be achieved. Obviously, the presence of the anomalous
electrical operating conditions observed during the test period
causes a significant degree of uncertainty in performance pro-
jections at other values of specific collecting area. Studies
with a hot-side pilot precipitator at the Navajo Station are
recommended to determine the relationship between dust layer
thickness, dust composition, and electrical operating parameters.
Particle charge measurements at the precipitator outlet are also
recommended to determine whether the existing model for calcu-
lating particle charging rates is valid for the conditions
observed at Navajo.
In view of the problems encountered in meeting the design
efficiency with the hot-side precipitator at Navajo, it is of
interest to examine possible design parameters for a cold-side
88
-------
unit collecting the same ash. The dust resistivities which
must be considered at 155°C are given below.
Source
Resistivity, ohm-cm (155°C)
Measured
(Laboratory Method)
Figure 16
Figure 17
Figure 18
Figure 19
Figure 20
Peabody Coal
Peabody Coal
Peabody Coal
Peabody Coal
Utah Coal
Predicted
6 x 1010
6 x 1010
7 x 1010
2 x 1010
7 x 101l
8.5 x 10
6 x 10
i o
i o
2.5 x 1010
1.8 x 101°
Not Available
These data illustrate that "worst case" values of resistivity for
the Peabody and Utah coals, respectively are 8.5 x 1010 ohm-cm
and 7 x 10 l ohm-cm. Estimated electrical operating parameters
for the cold-side model projections are 23.8 kV and 2.0 nA/cm2
for the Utah coal, and 25.8 kV, 9.9 nA/cm2 for the Peabody coal.
Figure 35 contains the model projections for cold-side
operating conditions at Navajo. These projections were obtained
using the geometrical configuration of the existing hot-side
precipitator and the particle size distribution measured at the
inlet to the hot-side unit. The estimated specific collecting
areas requirement for the Peabody and Utah coals at the design
efficiency of 99.5% are 106.3 m2/(m3/sec) (540 ft2/1000 acfm)
and 139.8 m2/(m3/sec) (710 ftz/1000 acfm), respectively. The
recommended specific collecting areas are increased over these
values by about 20% to allow a reasonable safety margin for
dust composition changes and mechanical problems with the
precipitator. The design configuration for the hot- and cold-
side units are given in the next section.
89
-------
99.9
j = 9.9 nA/cm2
V = 25,800 volts
j = 2.0 nA/cm2
V = 23,800 volts
600 700 800
118.1 137.8 157.5
SPECIFIC COLLECTING AREA
FT2/(1000cfm)
m2/(m3/sec)
Figure 35. Model projection for cold side operating parameters.
90
-------
SECTION 4
ENGINEERING ANALYSIS
CAPITAL AND OPERATING COSTS OF EXISTING UNIT
Table 23 presents the cost of Unit 3 precipitator in 1977
dollars. The 1977 costs were arrived at by taking the actual
contracted dollars assigned to Unit 3 precipitator for most of
the items in Table 23, adding a twenty percent distributable cost
to each, then adding nine percent of the contracted and distribu-
table costs for engineering costs and finally escalating each
cost element to 1977 at seven and one-half percent per year.
The precipitator and ductwork were purchased from Joy-
Western in 1973 and erection labor and subcontracts and equipment
insulation were assumed to be 1975 charges. The ash collection
and storage system was purchased in 1971 for all three units at
Navajo and the cost in Table 23 reflects one-third of that total
purchase. The installation of the ash collection and storage
system was assumed to have been completed in 1973. One-third of
the total was charged to the Unit 3 precipitator.
The charges associated with incremental costs of ESP to ID
fans, accessory electrical equipment, instrumentation, miscel-
laneous foundations, major auxiliary building foundations,
earthwork and architectural features were reported by the Bechtel
Corporation and were assumed to have been 1975 charges. The
majority of the ash handling machinery was purchased in 1974 and
the cost in Table 23 reflects one-third of the total equipment
cost in 1977 dollars.
The cost of the precipitator for Unit 3 in 1977 dollars is
$46.58/kW, based on the total of Table 23 and the design
generating capacity of Unit 3 of 750 MW ($43.67/kW for the 800 MW
operating point). The unit area costs of the entire precipitator
installation is $312/m2 ($29/ft2).
Table 24 presents the operating and maintenance costs
associated with the ash handling system which were charged to
Unit 3 from July 1, 1976 to July 1, 1977. The charges from the
electrical department and maintenance department are combined
since the majority of the work on the precipitator and associated
equipment requires that both departments be involved. The hourly
91
-------
TABLE 23
Unit #3 Precipitator Cost
1977 Cost
Item (7.5%/yr esca.)
#3 ESP 4,877,844.37
#3 ESP Labor & Subcontracts 3,852,960.07
#3 ESP Ductwork 3,304,863.69
Change in Materials 283,845.23
Accelerated Delivery of Materials 849,022.95
Equipment Insulation 2,155,481.00
Other Materials 227,755.50
Ash Collection & Storage System 4,275,476.12
Ash Collection & Storage System
Installation 3,575,686.57
Ash Handling Piping 483,861.84
Incremental Costs of ESP to
ID Fans 454,978.81
Accessory Electrical Equipment 7,637,144.27
Instrumentation 751,527.49
Misc. Foundations 721,737.22
Major Aux. Building Foundations 4,062.31
Earthwork 54,164.14
Architectural Features 844,960.64
Ash Handling Machinery 580,666.96
$34,940,000.00
92
-------
TABLE 24
Operating and Maintenance Costs for Unit #3, Ash Handling System,
July 1, 1976 to July 1, 1977
Description
Gallion Blade
Cat Loader
D4 Dozer
Ash Truck #138
Grad All
380 Dozer
Ash Truck #156
Ash Truck #161
Ash Truck #162
Ash Truck #179
Loader
Rental Scraper
Cost Adjustments
Electrical and/or
Maintenance Dept.
Misc.
Man
Hours
67
172
88
251
100
848
208
265
231
148
77
0
80
2477
37
Labor
565.79
1700.27
848.69
2591.24
1017.46
8451.24
1946.37
2643.41
2227.22
1431.55
739.41
0
96.26
105038.35
422.18
Materials
3365.22
3424.69
431.54
5920.05
1391.98
22342.49
12181.18
4749.67
4348.14
3848.83
642.64
0
90714.92
27206.23
98100.00
Contract
Services
0
914.33
0
3680.80
0
0
890.73
299.67
0
50.00
530.33
0
0
0
4944.00
Other
0
0
0
77.95
0
0
77.95
0
0
0
0
21302.00
128.85
0
524.00
Labor*
OVH
78.96
238.42
118.87
364.70
143.27
1196.63
271.91
385.48
313.66
201.30
102.41
0
38.50
14651.84
59.74
Total
4009.97
6277.71
1399.10
12634.74
2552.71
31990.36
15368.14
8078.23
6889.02
5531.68
2014.79
21302.00
$118,048.45
90978.53
147842.42
104049 .92
TOTAL
$342,870.87
$460,919.32
*Employee benefits: e.g., Workmans Comp., Insurance, Payroll
Taxes, etc.
-------
charges for maintenance or repair of equipment charged to the
separate areas (e.g., ash handling system, precipitator, etc.)
are recorded in total without a breakdown by department.
Table 25 presents the normal maintenance, repair and
operation charges for the Unit 3 precipitator from July 1, 1976
to July 1, 1977. These costs reflect maintenance items such as:
wire replacement, hopper service (high ash buildup in hoppers),
wire clinker removal, repair of electrical bus duct failures,
straightening of bowed collection plates, etc.
Table 25 does not include costs which would be associated
with routine checking or monitoring of the precipitator. The
estimated manhours for the separate departments, based on
maintenance starting with no deficiencies, required for normal
checking, monitoring or tuning of the precipitator are:
1) operations - 1 man, 30 minutes/shift; 2) electricians - 2 men,
8 hours/day; 3) mechanics - 1 man, 3 hours/day; 4) engineering
technicians - 2 men, 8 hours/day, 2 days/month; 5) engineering -
2 hours/week. These routine checks and monitoring duties total
an estimated 7,970 manhours/year/unit, which represent a cost of
$100,277 at $12.58/manhour.
Table 26 presents charges assigned to the Unit 3 precipi-
tator from July 1, 1976 to July 1, 1977 for testing, adjusting
and/or modifications of the precipitator. These charges include
the rewiring of the rapper control panels in order to separate
the wire rappers from the same programming card as the plate
rappers. The costs incurred during overhaul for the precipitator
included: installation of ladders at the inlet of each chamber
to provide access for the adjustment of the "zigzag" (gas
distribution) plates, installation of "egg-crate" gas distri-
bution devices in each chamber, installation of platforms in the
hoppers to provide access to the discharge and collection
electrodes, straightening of bowed collection plates, etc.
The estimated cost of electrical power to operate the Unit 3
precipitator is given in Table 27. The estimate of 2.5C per
kilowatt hour was used since SRP sells power for approximately
2.5C per kilowatt hour. The voltage current meter readings of
8/1-2/77 were used to calculate the power consumption of the
transformer rectifiers. The purge air system for the high-
voltage bus ducts and the ash system blowers were assumed to
operate at their maximum ratings. The incremental power
consumption of the ID fans was calculated using 12.7 mm (1/2
inch) pressure drop across the precipitator. Table 28 summarizes
the operating costs for the precipitator installation.
94
-------
TABLE 25
Operating and Maintenance Costs for Unit #3 ESP, Normal Maintenance,
Repair, and Operations, July 1, 1976 to July 1, 1977
Description
Cost Adjustments
Administration
Operations
Electrical and/or
Maintenance Dept.
Engineering
Misc.
Man
Hours
442.0
0
0
13993.5
1009.5
2.0
Labor
5103.31
0
0
114009.04
8777.59
15.20
Materials
26220.77
1459.32
15.79
29.84
84.99
5.00
Contract
Services
0
0
0
0
0
0
Other
0
0
0
0
697.30
0
Labor*
OVH
2092.34
0
0
15801.77
1226.69
2.06
Total
33416.42
1459.32
15.79
129841.65
10786.57
22.26
LFl
$175,542.01
*Employee benefits: e.g., Workmans Comp., Insurance, Payroll Taxes, etc.
-------
TABLE 26
Operating and Maintenance Costs for Unit #3 ESP, Charges for Testing,
Adjusting and/or Modifications, July I, 1976 to July 1, 1977
CFi
Description
Cost Adjustments
Administration
Operations
Electrical and/or
Maintenance Dept.
Engineering
Misc.
Overhaul Costs for Unit
#3 ESP,3/25/77-5/3/77
Man
Hours
49.5
0
10.0
5711.0
0
161.0
2181.5
Labor
505.35
0
109.38
53115.26
0
1724.47
23022.90
Material
19991.
35.
5.
2936.
312.
3.
279713.
43
66
00
87
16
82
221
Contract
Services
187206.00
0
0
0
0
0
483135. 302
Other
8434.99
0
0
94.28
204.84
44.00
22003.02
Labor*
OVH
202.14
0
14.84
7400.39
0
427.95
4424.45
Total
216,339
35
129
63,546
517
2,201
$282,769
$812,298
.91
.66
.22
.80
.00
.24
.83
.89
TOTAL $1,095,068.72
1. Includes $88,605.68 for"Egg Crate" gas distribution
devices and $188,421.79 for platforms in hoppers
2. Performed by CE, contract costs of $324,841.21 included
a. Zig Zag plate adjustments
b. "Egg Crate" installation
c. Permanent platforms in hoppers and hopper inspections
d. Straightening of bowed curtains (collecting plates)
e. Ladder installation to zig zag plates.
* Employee benefits: e.g., Workmans Comp., Insurance, Payroll Taxes, etc.
-------
TABLE 27
ESTIMATED POWER COST OF PRECIPITATOR
Item Energy Requirement, kW Cost/hr
Transformer rectifiers, 48 1,490 $37.25
Purge air system for high
voltage bus ducts
Heaters 425 $10.63
Blowers 37 $ .93
Ash system blowers 596 $14.90
ID Fans - incremental cost of
ESP 501 $12.53
1. Assuming a power cost of 2.5£/kWh.
TOTAL $76.24
97
-------
Energy Cost'1
Normal Operating &
Maintenance Cost
Ash Handling Cost
Sub-total
Capital Charges
34,940,000x.l5 =
Total
TABLE 28
SUMMARY OF OPERATING COSTS
$/yr mills/kWh
534,300 0.0953
276,
460,
1,271,
5,240,
6,511,
000
900
200
000
000
0.0492
0.0822
0.227
0.935
1.162
% of Total
Annual
Operating Costs
8.2
4.2
7.07
19.5
80.5
100.0
1. Based on 7008 hrs/yr at full load (800 MW) - 80% load factor
98
-------
OPERATING AND MAINTENANCE PROBLEMS
The Salt River Project organized a task force to discuss
possible means of improving precipitator performance and to
determine the reasons for the performance limitations. The task
force is composed of personnel from Western Precipitation,
Bechtel Corporation, Southern Research Institute, and the Salt
River Project. Some of the more significant problems which have
occurred with Unit 3 and which have been considered by the task
force include:
1. Gas velocity distribution,
2. Air infiltration,
3. Ash buildup in hoppers,
4. Transformer rectifiers, and
5. Rapper failure.
Gas Velocity Distribution
After Unit 3 began operation and the performance of the
precipitator was below the design value, the gas velocity distri-
bution was considered to be a possible problem. The Salt River
Project personnel obtained velocity distribution measurements
on a number of the chambers and discovered that the velocity dis-
tribution was extremely nonuniform. With the installation of
baffle plates at the edges of the zigzag plate gas distribution
devices, and adjustment of the zigzag slots, the gas velocity
distribution was improved to a normalized standard deviation
of 17%.
After gas flow model studies were conducted by Western
Precipitation, it was decided to install egg-crate gas distri-
bution devices at the inlet of each chamber to aid in obtaining
a uniform gas velocity distribution.
Air Infiltration
Leaking guillotine isolation dampers at the inlet of each
chamber were considered to be the major contribution of the
ambient air infiltration to Unit 3. Additional air infiltration
was contributed by leaking manholes and insulator compartment
doors. The replacement or addition of gasket materials helped
alleviate the majority of these problems.
Ash Buildup in Hoppers
The major maintenance problem with Unit 3 has been high ash
buildup in the hoppers which results in shorted fields, buckled
plates and broken wires. The malfunction of the Nuva feeders,
due to mechanical failures or clogging by foreign objects,
results in high ash levels. A major maintenance problem
following chamber shutdown has been access to the bottom of the
99
-------
high-voltage frames and collection plates. To alleviate this
problem, hopper platforms have been installed to allow easy
access to the wires and plates.
In an effort to detect ash buildup problems before the ash
level reaches the collecting plates, hopper-level indicators*
have been experimented with and have operated satisfactorily.
The installation of hopper-level indicator is planned at the
Navajo Station and should result in fewer maintenance charges and
higher reliability for the precipitator.
Transformer Rectifier
Only minor problems have been encountered with the high-
voltage system. There have been no electrical failures of the
TRs, but the following have required maintenance after the
problem was discovered.
o Gaskets had to be changed on the low-voltage bushings
of 3 TR sets after they began leaking pyranol.
o The low-voltage bushing cable termination was changed
from a clamp type connector to a crimp type connector.
Due to overheating, the clamp type connector would not
remain tight on the cable.
o The metering resistor from the TR set low-voltage
bushing terminal box was relocated to the AVC cabinets
in the control room due to overheating of the resistor.
o Sparking in bus ducts - infiltration of ambient air on
rainy days resulted in sparking in some of the bus ducts.
Rapper Failure
Failure of the impact rappers and controllers has been the
cause of maintenance associated with the rapping system.
Maintenance on the rapping system was reduced by installing
1) improved rapper wear rings, 2) flexible coil connectors to
the rappers, and 3) improved rapper control power relays. A
different rapper control was tested and considered to be
superior because: 1) it has demonstrated reliability, in that for
over five months operation has occurred with no problems, 2) it is
easier to set rapper impact than on present controller, and 3) it
is an updated control. An additional maintenance item associated
with the rapping system is the repair or replacement of rapper
seal boots which have leaked.
*K-Ray hopper level indicators.
100
-------
A major preventive maintenance effort by SRP has kept
maintenance problems to a minimum. Work is performed on the
Nuva feeders, rappers, insulator compartment ventilation system,
and TR sets on a weekly basis. Constant tuning and observation
of precipitator performance accounts for quick recognition and
service of problem areas.
Reliability
Although the precipitator has not operated reliably with
regard to its design efficiency, it has operated reliably from a
mechanical standpoint. Table 29 presents the percent of
available on-time for each chamber from July 1, 1976 to July 1,
1977, excluding unit overhaul. As discussed earlier, the major
cause for ESP down-time has been high ash buildups in the hoppers
due to malfunctioning Nuva feeders. As a result of the
preventive maintenance program established by the Salt River
Project and the system modifications, the reliability of the
precipitator is expected to increase over that experienced during
the past years.
Modifications
The modifications to Unit 3 precipitator have been performed
in an effort to improve precipitator performance and reduce
maintenance problems which have occurred. The majority of the
modifications were completed prior to Southern Research Insti-
tute's test of Unit 3 and are as follows:
© Rapper Optimization
The rapper controls were rewired to separate the wire
and plate rappers from the same programming card and to
lengthen the time between raps, especially for the last
fields.
A more reliable and versatile rapper controller will
replace the original controls as they fail.
® Hopper Ash-Level Detectors
Ash-level indicators have been studied and will be
placed on each hopper in an effort to reduce ESP internal
damage and down time.
o Platforms Within the Hoppers
Platforms were installed in each hopper to allow
access to the bottom of the collecting plates and high-
voltage discharge frames in order to reduce maintenance
time associated with high ash buildups and wire failures.
101
-------
TABLE 29
ESP CHAMBER AVAILABILITY
Chamber % Available1
1 96.8
2 94.3
3 100.0
4 100.0
5 100.0
6 100.0
7 97.1
8 98.7
9 98.5
10 100.0
11 97.2
12 100.0
13 99.6
14 98.9
15 98.6
16 96.9
1. Excluding unit overhaul.
102
-------
© Gas Distribution Systems
Installation of side plates of the zigzag gas distri-
bution devices was a necessary and early modification.
Extensive work on adjusting the zigzag plates was done by
SRP. The installation of egg-crate distribution devices
and ladders for access to the distribution devices was
completed in 1977.
© Changed Low-Voltage TR Connectors
The low-voltage bushing-cable termination connectors
were changed from the clamp type connector to a crimp type
connector due to overheating of the clamp type connector.
© Relocation of Metering Resistors
The metering resistors of the TR set low-voltage
bushing terminal box were relocated to the automatic
voltage control cabinets in the control room due to
failure of the resistor caused by overheating.
DESCRIPTION AND ESTIMATED COSTS OF AN IMPROVED PRECIPITATOR
The preceding section of this report has indicated the
rationale for the recommended hot-side design specific collecting
area of 93.9 m2/(m3/sec)(477 ft2/1000 acfm). Based on a gas flow
of 824 dsm3/sec (16 times the outlet value for Chamber 8), the
estimated total plate area required for the recommended SCA at
approximately 350°C is 206,200 m2 (2.217 x 106 ft2). The esti-
mated cost of this design was computed as follows:
® Cost in 1977 dollars assigned to the precipitator instal-
lation, excluding the I.D. fan incremental costs and the
ash handling system costs, was calculated on a dollar
per unit area basis.
o The total plate area of 206,200 m2 was used to calculate
the cost of the enlarged unit.
o The original cost of the ash handling system (1977 basis)
was scaled upward and added to the cost calculated for
the enlarged unit, along with the incremental I.D. fan
charges.
The above procedure results in a total estimated capital
cost of $60,440,000, or $75.5/kW, based on 800 MW generating
capacity. No retrofit charges are included in the estimating
procedure, since the objective is to estimate the cost of the
improved design in 1977 dollars for a new installation. The
103
-------
additional cost of the added collecting surface clearly predom-
inates over the cost of the previously discussed mechanical
improvements.
Comparison of Hot- and Cold-Side Designs
A comparison of hot- vs cold-side designs for the Navajo
Station precipitators is necessarily based on certain assumptions
regarding the required plate area and the design details of the
installation. The estimated plate area requirements were gen-
erated as described previously, and the basic geometrical con-
figurations of the recommended designs were arbitrarily chosen to
be the same as the existing installation. Table 30 contains the
recommended design parameters for one hot-side and two cold-side
conditions at Navajo. The enlarged hot-side unit represents an
increase in plate area of 83% over the existing unit. The added
collecting surface is expected to provide an adequate safety
margin to allow the design efficiency to be achieved in the
presence of the dust layer effects that limit operating voltages
which were observed during the test program.
The capital costs of the existing hot-side design were
compared with those obtained from a recent cost model published
by Research Cottrell, Inc.17 This cost model provides installed
cost for precipitators on a flange-to-flange basis, and gives a
value of $123/m2 ($11.4/ft2) for the existing design. From
Table 23 the sum of precipitator costs, labor and subcontracts,
insulation, and electrical equipment costs gives $165/m2 ($15.3/
ft2). This value is in reasonable agreement with the Research
Cottrell model, since a portion of the electrical and insulation
costs in Table 23 was for items not included in the flange-to-
flange model. These data imply that the total cost of the entire
precipitator installation and associated equipment at Navajo is
about 2.5 times the unit area installed cost of the precipitator.
For the recommended hot-side design in Table 30, the Research
Cottrell model gives about 42% of the total estimated precipi-
tator ash handling, duct work, and auxiliary equipment costs.
The estimated cost of the cold-side units was computed as
follows:
© The installed unit area cost, including ductwork and
auxiliaries but excluding the ash handling system costs,
of a cold-side unit was computed from recent data18 as
$133/m2($12.34/ft2) and used as a basis for calculating
the cold-side precipitator costs.
o A scaled value of the Navajo system ash handling costs,
and the I.D. fan incremental costs were added to the
expense for the precipitator installation to obtain the
estimated costs.
104
-------
TABLE 30
RECOMMENDED DESIGN PARAMETERS FOR IMPROVED PERFORMANCE
Condition
Gas flow, am3/sec
Gas flow, acfm
Temperature, °C
Electrical fields in
direction of gas flow
Collecting length, m
Collecting height, m
Area/chamber, m2
No. of chambers
Total collecting area,
m2
Hot-Side - Cold-Side - Cold-Side
Peabody Coal1 Peabody Coal1 Utah Coal1
Gas velocity, m/sec
Specific collecting area,
m2/(m3/sec)
ftVlOOO acfm
,, , / 2 i Model Inputs
Avg nA/cirr ) *
Collection efficiency, %
Design minimum
Expected
Dust resistivity, ohm-cm
Capital cost estimates (1977)
Total ESP system
$/kW at 800 MW
$/ft2
RC Model, flange-to-flange,
Installed, $/ft2
2,194
4,649,000
350
8
14.63
9.15
9,369
22
2.062xl05
1.36
93.9
477
29.0
40
99.50
99.70
5xl09
$61.44xl06
$76.8
$27.7
11.7
1,571
3,329,000 3
150
8
14.63
9.15
9,369
22
2.062xl05
0.976
131
666
25.8
9.9
99.50
99.77
8.5xl010
$41.92xl06
$52.40
$18.90
9.7
1,571
329,000
150
8
14.
9.
9,369
28
63
15
2.623xl05
0.767
167
848
23.8
2.0
99.50
99.75
7.0X101 :
$52.1xl06
$65.13
$18.46
9.4
1. Based on indicated dust resistivity values.
105
-------
The cold-side Research Cottrell cost model gives a value of
$104/m2 and $102/m2 ($9.66/ft2 and $9.44/ft2) for the suggested
cold-side design in Table 30. The Research Cottrell model thus
indicates that the hot-side units are about 20% more expensive
on a unit area and flange-to-flange basis. The total installa-
tion estimates in Table 30, however, indicate that the hot-side
installation is about 50% more expensive than the cold-side on a
unit area basis. Total cost for the two systems will, of course,
depend upon the relative plate areas and design details for the
ductwork.
106
-------
REFERENCES
1. Johnson, J. W., G. I. Clinard, L. G. Felix, and J. D. McCain.
A Computer-based Cascade Impactor Data Reduction System.
EPA-600/7-78-042, March, 1978.
2. Liu, B. Y. H., and D. Y. H. Pui. On the Performance of the
Electrical Aerosol Analyzer. J. Aerosol Science, 6, pp. 249-
64 (1975).
3. Nichols, G. B. Techniques for Measuring Fly Ash Resistivity.
EPA-650/2-74-079, August, 1974.
4. Bickelhaupt, R. E. Measurement of Fly Ash Resistivity Using
Simulated Flue Gas Environments. EPA-600/7-78-035, March,
1978.
5. Lisle, E. S., and J. D. Sensenbaugh. Combustion 36(1),12 (1965).
6. Smith, W. B., and R. R. Wilson, Jr. Development and Laboratory
Evaluation of a Five-Stage Cyclone System. EPA-600/7-78-008,
January, 1978.
7. Cahill, T. A., et al. Monitoring of Smog Aerosols with Elemental
Analysis by Accelerator Beams. National Bureau of Standards
Special Publication 422, issued August, 1976.
8. Hoel, Paul G. Introduction to Mathematical Statistics, 3rd
Ed., John Wiley and Sons, Inc., New York. p. 276.
9. Marlow, W. H., P. C. Reist, and G. A. Dwiggins. Aspects of the
Performance of the Electrical Aerosol Analyzer under Non-Ideal
Conditions. J. Aerosl Sci. 1976, Vol. 7, p. 457.
10. Ensor, D.S., e_t al. Evaluation of a Particulate Scrubber
on a Coal Fired Utility Boiler. EPA-600/2-75-074, 1975.
11. Ensor, D. S., R. G. Hooper, and R. W. Scheck. Determination
of the Fractional Efficiency, Opacity Characteristics, Engineering
and Economic Aspects of a Fabric Filter Operating on a Utility
Boiler. Electric Power Research Institute Report No. EPRI FP-297.
November 1976.
12. Leutert, G., and B. Bohlen. The Spatial Trend of Electric Field
Strength and Space Charge Density in Plate Type Electrostatic
Precipitators. STAUB. 32(7), July, 1972.
13. Gooch, J. P., J. R. McDonald, and S. Oglesby, Jr. A Mathematical
Model of Electrostatic Precipitation. EPA-650/2-75-037, April,
1975.
107
-------
14. McDonald, J. R., W. B. Smith, H. W. Spencer, and L. E. Sparks.
A Mathematical Model for Calculating Electrical Conditions in
Wire-Duct Electrostatic Precipitation Devices. J. Appl. Phys.,
48(6): 2231-2246, 1977.
15. McDonald, J. R., and J. P. Gooch. Report in preparation to the
Environmental Protection Agency under Contract No. 68-02-2193.
16. Gooch, J. P., and G. H. Marchant, Jr. Electrostatic Precipitator
Rapping Reentrainment and Computer Model Studies. Electric
Power Research Institute, Final Report Draft, EPRI Contract
RP413-1, Task 1.1 and 1.3, August, 1977.
17. Bubenick, David V. Economic Comparison of Selected Scenarios
for Electrostatic Precipitators and Fabric Filters. J. of the
Air. Pollution Control Assoc., 28(3), March, 1978, p. 279.
18. Stearns-Roger, Incoporated. Engineering Analysis of the Neal
Station Unit No. 3 Cold Side Electrostatic Precipitators,
prepared for Meterology Research Incorporated, August, 1977.
108
-------
APPENDICES
Appendix 1 Description of Methods
Appendix 2 Impactor Substrate Weight Changes for Blank
Runs
Appendix 3 Voltage-Current Data
Appendix 4 Size-Dependent Elemental Concentration Data
109
-------
APPENDIX 1
DESCRIPTION OF METHODS
110
-------
MASS MEASUREMENT SYSTEM
Mass measurements were conducted at the inlet and outlet
sampling locations as outlined in EPA Method 17.l The main
difference between EPA Method 17 and the EPA Method 5 is the loca-
tion of the particulate filter in the stack. With this arrangement,
a thimble-shaped filter (Figure 1-1) is used to sample high mass
concentrations and a conventional, disk-shaped, filter is used
for low mass concentrations. The advantage of this system is
that the particles are trapped before they enter the probe and a
probe wash is not required. A condenser and gas cooler are still
required between the probe and the gas metering system. The
pitot tube, pump, and other parts of the system are similar to
the EPA Method 5 Sampling Train that is shown in Figure 1-2. The
thimble-filter system has often been used in engineering tests
to evaluate the performance of a control device. In general,
this system is easier to use than the EPA Method 5 Sampling
Train. The main advantages are the elimination of the probe
wash routine and greater flexibility in the placement and mounting
of the larger and bulkier components of the system, especially
the impinger box, that is available when the rigid probe-filter/
impinger box connection is eliminated. If a ceramic thimble
is used, the technique is sometimes referred to as the "ASME
Method" (American Society of Mechanical Engineers). Calcula-
tion of mass concentrations from the data obtained with this
sampling system were performed using standard methods as those
found in Reference (1).
CASCADE IMPACTORS
Cascade impactors were used to obtain particle mass and
particle size distribution entering and leaving the electro-
static precipitator for the diameter range 0.5 to 10 ym.
Particle separation by size interval takes place within cas-
cade impactors by passing the sample gas stream sequentially
through a series of dry impingement type inertial classifiers.
The classifiers operate by impingement of the aerosol stream as
an air jet against a plate, causing the gas in the jet to
sharply change direction and flow around the plate. Because of
inertia, particles leave the flow streamlines and are deposited
on the plate. Each impingement stage in the series operates at
a higher impingement velocity (or as a higher energy separator)
than the previous stage. Depending on the desired sampling rate
and jet velocities the stages may contain single or multiple jets.
1. Environmental Protection Agency. Determination of Particu-
late Emissions from Stationary Sources (In-stack Filtration
Methods). Federal Register 43(37):7584, February 23, 1978.
Ill
-------
SAMPLING
NOZZLE
GLASS FIBER THIMBLE FILTER
HOLDER AND PROBE(HEATED)
CHECK
VALVE
REVERSE-TYPE
PITOT TUBE
DRY TEST METER
AIR-TIGHT PUMP
Figure 1-1. Arrangement for Mass Concentration Measurements
with Thimble-shaped Filters
-------
IMPINGER TRAIN OPTIONAL:
MAY BE REPLACED BY AN
EQUIVALENT CONDENSER
HEATED PROBE
1
HEATED
AREA FILTER HOLDER
THERMOMETER
CHECK
VALVE
MANOMETER DRY TEST METER AIR TIGHT PUMP
Figure 1-2. Particulate Sampling Train
113
-------
A typical single-jet impactor is the Brink impactor which
operates at a flow rate of about 1.18 x 10~5 m3/sec (0.025 cfm) ,
while typical multijet impactors are the Andersen and University of
Washington impactors which operate at flow rates of about 2.36 x
10~" m3/sec (0.5 cfm). By operating the impactors i.n situ, un-
certainties due to probe losses are avoided. However, the impac-
tors must operate at a constant flow rate in order to maintain
the various size fractionation diameters of the stages at fixed
values. Thus even though traverses are made, isokinetic sampling
cannot be maintained. Instead, a suitable flow rate and nozzle
diameter are chosen which will best approximate isokinetic sampling
over the traverse area.
During the test program modified Brink impactors were used at
the inlet sampling locations and Andersen Mark III impactors were
used at the outlet sampling locations. Reeve Angel 934 AH glass
fiber substrate material which had been acid washed and conditioned
in situ was used in each impactor during the test program. Sampling
procedures as outlined by Harris2 were followed.
Once the impactor stage weights were obtained, data reduction
procedures as outlined below were followed.
1. Stage weights were corrected for "blank" weight gains.
2. Cut points for the individual stages for each impactor
were calculated based on calibration studies conducted
in the laboratory using polystyrene latex beads for
sizes smaller than 2.0 ym diameter and ammonium fluore-
scein particles for particle diameters from 2 to 8 ym
diameter. Glass fiber substrates were in place for the
calibration studies.
3. Impactor runs were arranged in groups in an appropriate
manner for the test program.
4. The data were then used as input to a computer program3
which calculates the size distribution and fractional
efficiencies.
2. Harris, D. Bruce. Procedures for Cascade Impactor Calibration
and Operation in Process Streams. Environmental Protection
Technology Services, EPA-600/2-77-004, January 1977.
3. Johnson, J. W., G. I. Clinard, L. G. Felix, and J. D. McCain.
A Computer-based Cascade Impactor Data Reduction System.
EPA-600/2-78-0242, March 1978.
114
-------
A detailed description of the data reduction program is
available in the EPA publication, "A Computer-based Cascade
Impactor Data Reduction System."3 A brief outline of the opera-
tions performed by the program is given below.
1. Individual impactor runs are fit with a series of seg-
mented polynomials (spline fit) which are continuous
at the points of overlap in the first derivative with
respect to particle size.
2. The "spline fits" for all runs are arranged in the
groups desired.
3. The polynomials are differentiated to obtain values of
dM/dLOGD at fixed particle sizes. All particle diameters
are "Stokes diameter", defined as the diameter of a
sphere having the same density which exhibits aerodynamic
behavior identical to the particle of interest. Average
density values are used which are obtained from helium
pycnometer determinations.
4. Average values of dM/dLOGD are calculated for the fixed
particle sizes from the members of each group, and an
outlier analysis is performed. If the analysis results
in certain values being discarded, a new average is com-
puted without the outliers. Fifty percent confidence
intervals are then computed.
5. The averaged values of dM/dLOGD are ratioed to calcu-
late penetration values at the fixed particle diameters.
Fifty percent confidence intervals for the penetrations
are also calculated.
6. The functions determined by the averaged dM/dLOGD values
are integrated to obtain corresponding cumulative
distributions.
7. The program then plots the size distributions and the
penetrations in the desired format.
Page 117 presents the computer printout for one of the
Andersen impactors which was operated during the test series and
the data reduced using the computer program referenced above.
The remainder of the impactor data from this test program is
available through the Fine Particle Emissions Information System,
in care of Mr. Gary L. Johnson, Special Studies Staff (MD-63),
Industrial Environmental Research Lab, Environmental Protection
Agency, Research Triangle Park, N.C. 27711.
Table 1-1 contains the calibration constants in the form of
/T" for each of the impactors used in the test program.
115
-------
1NGSO-5 7-M-77 ?, 3, a, 5, 6, 7, l i?30« OUTLET SAMPLE ANDFRSEM MfinEL II! STACK SAMP( ER NUMBER • 619
IMPACTOR (-LDWRATF = 0.308 ACFM IMPACTOR TEMPERATURE = 621.0 F r 32fl.3 c SAMPLING DURATION » 126.00 MIK
IMPACTOR PRISSURF DPnP z 0.1 IN. nf HG STACK TFMPERATukF. = 623.0 F = 32B.3 C
ASSUMED PARTICLE PFNSITV = ?'.«! GM/CM.CM. STACK PRFSSURE = ?a.6<» IN. OF HC MAX. PARTICUE DIAMETER = 12.0 MICROMETERS
GAS COMPOSITION (PERCENT) CO? c 13.86 CO = 0.00 N2 = 73.11 OS » 1 .SO H20 o 8.80
CALC. MASS LOADING = 5.137HE-OJ GR/ACF 1.3776F-0? GR/DNCF 1.1757E+01 MQ/ACM J.1S21E+01
IMPACTOR STAGf SI S? S3 SU S5 86 37 SB
STAGE INDEX NUMRFR 123056789
D50 (MICROMETERS! 10.T7 10. «3 6.3T «,22 2.«5 1.16 0,62 0.27
MASS (MILLIGRAMS) 2.60 0.69 0.23 0.11 1.67 1.77 2.95 2.15 0,75
MG/ONCM/STAGE 6.U3E+00 1.71E+00 5.69E-01 2.72E-01 a.lJE+00 a.38E+00 7.30E*Ofl 5.32E400 l,fl5E»00
CUM. PERCENT OF MASS SMALLER THAN D50 79.8B 71.51 72.76 71.90 58.98 «5.28 22. «5 5.80
CUM. (MG/ACM) SMALLER THAN D50 9.39E+00 8.76E*00 8.55E*00 8,«5E*00 6.93E+00 S.3?r»00 P.60F+00 6.82E-01
CUM. (MG/DNCM) SMALLER THAN 050 2.52E+01 2.S5E»01 2.29E*01 2,27E*01 1.86E*01 l.a3E+01 7.0BF+00 1.B3E+00
CUM, (GR/ACF) SMALLER THAN 050 U.10F-03 3.R3E-03 3.7UF-03 3.69F-03 3.03E-03 2.33E-03 1.15E-03 2.9BE-01
CUM. (GR/pNcF) SMALLER THAN D50 1 , 1 OF=0? 1.03E-02 l.OOE-02 9.91E-OS 8.12E-03 6.21E-03 3.09F=03 8,OOE-0«
GFO, MEAN DIA. (MICROMETERS) l.PhEtOl 1.06F + 01 8.16f: + 00 5.19E + 00 3.21E + 00 1.70F.»00 fl.53F-01 d.06E»01 1,89E = 01
DM/OLOGO (MG/DNCM) 1.36E+01 1.25E»02 2.66E+00 1.52E+00 1.7UE»01 1.38E+01 2,62E*01 1,«5E»01 6,16E«00
DN/DLOGD (NO. PAKTICLES/DNCM) ),68E»06 R.32F*n7 3.BBE + 06 8.63F. + 06 U.16E + OB 2.23E»09 3,3«F+10 1.72E + I1 7,?9E»11
NORMAL (FNGINEFRING ST«Nn«Rn) rnNOITInNS API ?1 DEC C AND 760MM HG.
SOUARf ROOTS OF PSI BY STAGE 0.305 O.«30 O.«t0 0,385 0.1U2 0.37Q O.J52 0,272
COLE niAMfTERR HV STAGE (CENT IM£TFWS) 0.1621 0.1263 0.09U6 0.0757 0,0581 0.035S 0.0258 0.02«5
-------
TABLE 1-1
Values for Cascade Impactor Stages
Stage 0
Andersen
Andersen
Andersen
Andersen
Andersen
Brink
Brink
Brink
Brink
229
231
583
619
627
A
B
C
D
.305
.305
.305
.305
.305
.322 .322
.322 .322
.322 .322
.322 .322
.430
.430
.430
.430
.430
.338
.349
.351
.346
.410
.410
.410
.410
.410
.345
.330
.388
.354
.385
.385
.385
.385
.385
.258
.302
.330
.297
.328
.332
.341
.342
.344
.317
.345
.350
.337
.319
.313
.320
.370
.335
.229
.175
.273
.226
.364
.365
.331
.352
.339
.283
.280
.274
.272
.278
Stage 1 through 4 of the Andersen impactor and stages 1 through 3 of the Brink
impactor were calibrated with ammonium fluorescein while stages 5 through 8 of
the Andersen impactors and 4 through 6 of the Brink impactors were calibrated
with polystyrene latex spheres. During the calibration of each impactor stage,
glass fiber substrates were in place.
-------
ELECTRICAL AEROSOL ANALYZER (EAA)
A Thermo-Systerns Inc. Model 3030 Electrical Aerosol Analyzer
(EAA) was used at the inlet and outlet sampling locations to deter-
mine concentration vs. size information in the diameter range of
0.01 to 0.3 ym. This system is shown in Figure 1-3. The EAA
operates by placing a known charge on the particles and precipi-
tating the particles under closely controlled conditions. Size
selectivity is obtained by varying the electric field in the
precipita'-.or section of the mobility analyzer. Charged particle
mobility is monotonically related to particle size in the operating
regime of the instrument (0.01 to 0.3 ym).
The instrument used for field work by SRI personnel had been
slightly modified for ruggedness and convenience. A set screw
was installed on the Flow Straightener Cylinder to prevent the
spring-loaded electrical contacts from vibrating loose (recent
production units of the EAA incorporate this modification), the
electrometer connectors were replaced with push-on, quick-disconnect
circular connectors, and a "compression tube fitting" assembly
connected to the sample inlet allows the Sheath Air Flow and
Sample Air Flow to be drawn from separate locations. Output
of the EAA was recorded both manually (in digital form) and on
a chart recorder (Hewlett Packard Model 7100B, Electric Write).
Data Reduction Procedures
Once the equipment has been set up as shown schematically in
Figure 1-4, the flows are adjusted through the sample orifice and
the dilution air orifice, to obtain the desired dilution factor.
The EAA is placed in a manual scan mode and the current readings
for each channel are recorded with a strip chart recorder. Manual
control allows run times of from two to five minutes in each of
the nine channels. This allows one to average out rapid source
fluctuations. At the beginning of each day the internal calibra-
tion points and flows through the EAA are checked, as described in
the instrument manual. These are also periodically rechecked
throughout the day.
The theory of operation and basic equations for the EAA have
been given by Liu et al4 and calibration of the Model 3030 EAA has
been done by Liu and Pui5 which revises the previous calibration.
Table 1-2 shows these revised calibration constants in a data
reduction format. The calibration by Liu suggested the use of a
calibration matrix; however, typical source fluctuations in
4. Liu, B.Y.H., K. T. Whitby, and D.Y.H. Pui. A Portable Electrical
Aerosol Analyzer for Size Distribution Measurements of Sub-
Micron Aerosols. Presented at the 66th Annual Meeting of the
Air Pollution Control Association, Paper No. 73-283 (June 1973).
5. Liu, B.Y.H., and D.Y.H. Pui. On the Performance for the Elec-
trical Aerosol Analyzer. J. Aerosol Science, 6, pp. 249-64
(1975).
118
-------
CONTROL MODULE
ANALYZER OUTPUT SIGNAL -
DATA READ COMMAND - -
CYCLC START COMMAND -
CYCLE REJtT COUIUMO-
AEROSOL FLO»M£TER READOUT
CMARvXP CURRCNT READOUT
- - CHAPGCR VOLTAGE RIADOUT
AUTOMATIC MICH VOLTAOC CONTROL AMD READOUT
ELECTROMETER (ANALYZER CURRENT) RCACOUT
TOTAL FLOWMtTCR READOUT
CITCmiAL
DATt
'ACQUISITION
IYJTCM
TO VACUUM PUHf>
Figure 1-3. Schematic Diagram of the Electrical Aerosol Analyzer
(Liu and Piu")
-------
to
o
DUMP
BLEED
TIME
AVERAGING
CHAMBER
DILUTION DEVICE
CHARGE NEUTRALIZER
^H°HH ——
----------:Ulk-<:L-
PROCESS EXHAUST LINE
CHARGE NEUTRALIZER
CYCLONE
ORIFICE WITH BALL AND SOCKET
JOINTS FOR QUICK RELEASE
SOX ABSORBERS (OPTIONAL! -
HEATED INSULATED BOX
RECIRCULATED CLEAN. DRY, DILUTION AIR
^3-J|.
o
FILTER BLEED NO. 2
MANOMETER
COOLING COIL
3630 036
PRESSURE
BALANCING
LINE
DRYER
-=EX] BLEED NO. 1
Figure 1-4. Sample Extraction-Dilution System
-------
TABLE 1-2
EAA (Model 3030) Data Reduction Form
Concentration, Cumulative Concentration, and AN /ALogD from Scan No
1
Channel
No.
3
4
5
6
7
8
9
10
11
2
Collector
Voltage D
196
593
1220
2183
3515
5387
7152
8642
9647
0
0
0
0
0
0
0
0
0
3
p, Um
.0100
.0178
.026
.036
.070
.120
.185
.260
.360
4
Dpi, urn
0
0
0
0
0
0
0
0
.0133
.0215
.0306
.0502
.0917
.149
.219
.306
for DF =
5
AN/AI
4
2
1
8
4
2
1
1
.76xl05
.33xlOs
.47xl05
. 33x10"
.26x10"
.47x10"
.56x10"
.10x10"
6
AlogD
0
0
0
0
0
0
0
0
.250
.165
.141
.289
.234
.188
.148
.141
a
7 8 9 10 11 12
I,pA AI,pA AN AN ZN AN /AlogD
s s s
-------
industrial processes generally negate any potential advantage of
such refinements. Table 1-2 is essentially self-explanatory.
The heading "Dp, pin" (column 3) is the particle diameter in
microns. A value of 0.0100 means that the center rod voltage is
such that all particles of 0.0100 ym diameter and smaller are
collected in the analyzer tube while larger particles penetrate
to the current collecting filter where an electrometer measures
the total current carried by the unprecipitated particles. This
current represents the charges on all particles larger than 0.0100
ym. This measured current is the basic output of the Model 3030.
The fourth column (Dpi,ym) is the geometric mean diameter of
the particles represented by the current difference of two
successive steps (Channel No.'s). For example, the difference
in current for the 0.0100 ym cut-off and the current for the
0.0178 ym cut-off is the total current collected from particles
between these sizes, or rather for a mean diameter of 0.0133 ym.
The current differences are entered in column 8 headed "AI,pA"
(picoAmps).
The fifth column gives the revised calibration factor (based
on the calibration by Liu and Pui5) for each of the eight size
bands. These factors are in units of particles per cm per
picoAmpere. Multiplying this size specific current sensitivity,
AN/AI, (column 5) by the current difference, AI (column 8) gives
the total number of particles, AN, (column 9) in units of particles
by cm3, within this size band (column 4) for the diluted aerosol.
To correct for dilution and find in-stack concentrations, multiply
column 9 by the dilution factor (DF) and enter the result, .ANS,
in column 10. Columns 6 and 12 are used for ANs/ALOGD information
calculated from the number distribution in column 10. Column 11
is used for cumulative concentrations, corrected for dilution
to engineering standard (normal) conditions by a dilution factor
(i.e. column 10). Engineering standard or normal conditions are
defined as 21°C and 760 mm Hg pressure.
The basic data from the EAA is cumulative current for each of
nine channels (column 7). One must then take the differences of the
current readings for successive channels (column 8) in order to find
AN, etc. These AI values are multiplied by a series of constants
(AN/AIi, DFj) to arrive at ANS (concentration in stack corrected
to dry, standard conditions). While a single scan should be made
at a constant dilution, different scans may be made at different
dilutions. To simplify the arithmetic for each test condition,
we form the product ctj_ = Alj_,j x DFj and average all such inlet
(outlet) products for the same size band. This average is used in
Table 1-3 to calculate Ns, cumulative concentration, and ANS/ALOGD
for each size band. When Table 1-3 is used the data reduction is
as follows:
122
-------
TABLE 1-3
EAA (Model 3030) Data Reduction Form
Concentration, Cumulative Concentration, and AN /ALogD
From Average a for Condition
1
Channel
No.
3
4
5
j — i
NJ 6
U)
7
8
9
10
11
2
Collector
Voltage
196
593
1220
2183
3515
5387
7152
8642
9647
3
D
P
0.
0.
0.
0.
0.
0.
0.
0.
0.
, pm
0100
0178
026
036
070
120
185
260
360
4
P
0.
0.
0.
0.
0.
0.
0.
0.
• / um
0133
0215
0306
0502
0917
149
219
306
5
AN/AI
4.
2.
1.
8.
4.
2.
1.
1.
76xl05
33xl05
47xl05
33x10"
26x10"
47x10"
56x10"
10x10"
6789 10
AlogD a AN IAN AN /AlogD
p s s s
0.
0.
0.
0.
0.
0.
0.
0.
250
165
141
289
234
188
148
141
-------
Summary of the Calculation Format
STEP 1
A. Calculate the average instrument reading (I) for each channel
as obtained from the strip chart recording of channel current vs.
time .
B. Calculate all dilution factors (DFj).
STEP 2
Calculate current differences (AIj^j) from adjacent channels and
average the i products (cti = AI^ . s DFj) for the same size band
for all scans taken for the same test conditions. Calculate 90%
confidence intervals for each o"i . Note: the i subscript denotes
size and the j subscript denotes dilution setting.
STEP 3
Using OLJ_ and Table 1-2 calculate "number concentration" (ANg) ,
"average cumulative concentration of all particles having diameter
greater than the indicated size" (£ANS) , and "ANS/ALOGD" for each
size band for each test condition.
STEP 4
Plot "Cumulative Concentration vs. Size" for each test condition.
STEP 5
Plot ANS/ALOGD [with upper and lower (50% or 90%) confidence limits]
vs. size for each test condition.
RESISTIVITY MEASUREMENT SYSTEMS
Resistivity measurements were obtained with an ASME Power
Test Code 28 apparatus, and a point-to-plane probe, for conducting
the laboratory and in situ measurements, respectively, as
described below.
LABORATORY MEASUREMENTS
The basic conductivity cell is shown in Figure 1-5. It
consists of a cup which contains the ash sample and which also
serves as an electrode, and an upper electrode with a guard ring.
To conform with the code, the high-voltage conductivity cell must
have the same dimensions as shown, and must use electrodes con-
structed from 25-micron porosity sintered stainless steel.
124
-------
MECHANICAL
GUIDE
(INSULATED)
1/32 IN.
AIR GAP
GUARD RING
1-1/8 IN. DIA. BY
1/8 IN. THICK
DUST CAP
3 IN. ID, 5 mm DEEP
MOVABLE ELECTRODE
3/4 TO 1 IN. DIA.
BY 1/8 IN. THICK
TO HIGH VOLTAGE SUPPLY
0700-14.22
Figure 1-5. Bulk Electrical Resistivity Apparatus, General Arrangement
The movable disk electrode is weighted so that the pressure on the dust
layer due to gravitational force is 10 grains per square centimeter. The
nominal thickness of the dust layer is 5 millimeters. The actual thickness
is to be determined with the movable electrode resting on the surface of
the dust. All electrode surfaces in the region of the dust layer are to
be well rounded to eliminate high electric field stresses.
125
-------
The controlled environmental conditions required for the
measurement of resistivity in the laboratory can be achieved
by an electric oven with thermostatic temperature control and
with good thermal insulation to maintain uniform internal tempera-
ture, and a means to control humidity. Humidity may be controlled
by any one of several conventional means, including circulation
of preconditioned gas through the oven, injection of a controlled
amount of steam, use of a temperature-controlled circulating
water bath, or the use of chemical solutions which control water
vapor pressure. It is desirable to circulate the humidified
gas directly through the dust layer; hence the reason for the
porous electrodes. Figure 1-6 illustrates a set-up for resis-
tivity measurements similar to the one presently in use in our
laboratories. However, the present set-up has the capability
of providing a simulated flue gas environment.
Our standard procedure for laboratory resistivity measure-
ments can be used to obtain data from 84 to 460°C. The ash is
thermally equilibrated at 460°C overnight in a dry nitrogen at-
mosphere. The test environment, which will consist of a mixture
containing H20, 02, C02, S02, and the balance N2, is then intro-
duced, and current is measured every ten minutes thereafter until
the current increases less than 10% in a ten minute period.
At this point, it is assumed that the ash and environment are
reasonably equilibrated, and the oven is turned off. As the
temperature decreases, the current is determined for every 30
to 40°C drop in temperature under an applied electric field.
Point-to-Plane Probe for In Situ Measurements
The point-to-plane probe is shown in Figure 1-7. The probe
is inserted directly into the dust-laden gas stream and allowed
to come to thermal equilibrium. The particulate sample is de-
posited electrically onto the measurement cell through the elec-
trostatic action of the corona point and plate electrode. A
high voltage is impressed across the point and plate electrode
system such that a corona is formed in the vicinity of the point.
The dust particles are charged by the ions and perhaps by free
electrons from this corona in a manner analogous to that occurring
in a precipitator.
The dust layer is formed through the interaction of the
charged particulate with the electrostatic field adjacent to
the collection plate. Thus, this device is intended to simulate
the behavior of a full-scale electrostatic precipitator and to
provide a realistic value for the resistivity of the dust that
should be comparable to that in the actual device.
126
-------
Environmental sampling port
PTC 28 apparatus
\
Externally heated piping
mV Potentiometer
Power
source
for oven
Externally heated exit piping
/
Calibrated C/A thermocouple
Cold junction
Fritted disc
Environmental chamber
Fritted disc air bubbler
Bath water
Overflow
Make-up water reservoir
Pump
^
Constant temperature bath
Pressure regulator
Air flowmeter
Air tank
Figure 1-6. Schematic of Apparatus Set-up for Resistivity Measurements
-------
HIGH VOLTAGE
CONNECTION
DIAL INDICATOR
MOVABLE
SHAFT
STATIONARY
POINT
GROUNDED
RING
3630-009
(0700-14.24)
Figure 1-7. Point-to-plane resistivity probe.
120
-------
In the point-to-plane technique, two methods of making
measurements on the same sample may be used. The first is the
"V-I" method. In this method, a voltage-current curve is ob-
tained before the electrostatic deposition of the dust, while
the collecting disc is clean. A second voltage-current curve
is obtained after the dust layer has been collected. After the
layer has been collected and the clean and dirty voltage-current
curves obtained, the second method of making a measurement may
be used. In the second method, a disc the same size as the col-
lecting disc is lowered on the collected sample. Increasing
voltages are then applied to the dust layer and the current ob-
tained is recorded until the dust layer breaks down electrically
and sparkover occurs. The geometry of the dust sample, together
with the applied voltage and current, provide sufficient informa-
tion for determination of the dust resistivity.
In the point-to-plane method, the voltage drop across the
dust layer is determined by the shift in the voltage-vs-current
characteristics along the voltage axis as shown in Figure 1-8.
The situation shown is for resistivity values ranging from 109
to 1Q1 * ohm-cm.
If the parallel disc method is used, dust resistance is
determined from the voltage measured just prior to sparkover.
In both methods the resistivity is calculated as the ratio of
the electric field to the current density.
The practice of measuring the resistivity with increasing
voltage has evolved because the dust layer behaves as a nonlinear
resistor. As the applied voltage is increased, the current in-
creases greater than that attributable to the increase in volt-
age. Therefore, as described in the A.S.M.E. Power Test Code
Number 28 procedure, the value just prior to sparkover is re-
ported as the resistivity.
SAMPLE CALCULATIONS FOR DATA REDUCTION OF RESISTIVITY MEASUREMENTS
After all data has been recorded for the point-to-plane
resistivity probe, Figure 1-9, the resistivity can be calculated
by using the following equation:
V A
0 = — • —
M I L
where:
p = resistivity, ohm-cm.
V = voltage or voltage drop when calculating resistivity
from the V-I method, volts.
I = current at voltage used to calculate resistivity, amps.
129
-------
3.Or
2.5
o
2.0
, _
2 1.5
UJ
UJ
o:
cc
3 1.0
0.5
8 12
VOLTAGE , KV
SPARK
NO DUST
DEPOSIT ON
PLATE
VOLTAGE DROP ACROSS
DUST LAYER(Vd) FOR
DUST THICKNESS
(xd) = 0.001 METER
16
20
Figure 1-8. Typical voltage-current relationships for
point-to-plane resistivity probe.
130
-------
Area = 5 cm'
V-I DATA
VOLTS
XV
1
2
3
4
5
6
7
fi-
q
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
AMPS .
CLEAN
Start
.20 yA
.38 yA
. 57 yA
.88 yA
Spark
DIRTY
Start
.17 yA
.29 yA
.48 yA
.75 yA
Spark
Date May 31, 1977
Time 12:00 - 1:00
Place Coal Fired Power
Plant
Temp. 655°F (346°C)
Cell Depth 1.0 mm (.1
Location Inlet Port 3
Test }? 1
cm)
SPARK DATA
VOLTS
100
200
300
400
500
600
vnn
800
900
1000
1100
i?no
1300
1400
1500
1600
1700
IflOO
1900
2000
2100
2200
2300
2400
2500
?£nn
97nn
2800
2900
3000
3500
4000
4500
AMPS
.13 yA
.45 yA
.81 yA
1. 0 yA
1.2 yA
1.9 yA
2.4 yA
2.7 yA
Spark
E = V/cm
1000
2000
3000
4000
5000
6000
7000
8000
RESISTIVITY
E ' A
P = I
3.8X101 °
2.2xl010
1.85xl010
2.0xl010
.OxlO10
1.6xl010
I.SxlO10
LsxlO10
Figure 1-9.
131
Resistivity Field Data Sheet
-------
A = cross sectional area of sample, cm2.
L = depth of the sample, cm.
From Figure 1-9, the V-I data can be graphed as in Figure 1-10,
and the resistivity calculated.
V-I Data,
AV A
p =
400V 5 cm2
. cm
= 4 x 101 ° ohm-cm.
Also, from Figure 1-9, the resistivity can be calculated at each
applied voltage from the spark data with the same equation.
Gas Analysis System
Flue gas constituents of oxygen and carbon dioxide were
determined, entering and leaving the precipitator with commercial
Orsat-type apparatus. Two Orsat-type analyzers were used to
determine oxygen content of the gas entering and leaving the
precipitator simultaneously.
The flue gas was sampled for S02 and S03 using a sampling
technique developed under previous EPA contracts. The technique
is illustrated in Figure 1-11, and is similar to one described
by Lisle and Sensenbaugh. 6
The sampling probe includes two concentric tubes with lengths
of 1.2 m; the inner tube or sampling line is made of Pyrex with
an interval diameter of about 7 mm, and the outer tube used for
support and insulation is made of stainless steel with an ex-
ternal diameter of about 25 mm. The annulus between the two
tubes contains an electrical heating tape around the wall of
the Pyrex tube and an insulating asbestos tape around the heating
tape. The end of the Pyrex tube that is inserted in the flue
is packed with quartz wool to prevent particles of fly ash and
H2S0lt-H20 condensate from entering the collection system; the
other end of the Pyrex tube is fitted with a ball-and-socket
joint for connection to the condenser. The condenser consists
6. Lisle, E.S., and J.D. Sensenbaugh. Combustion 36(1),12 (1965)
132
-------
1.5
1.0
UJ
DC
CC
o
0.5
CLEAN PLATE DATA
DIRTY PLATE DATA
P =
AV
I
400V
0.5/uA
5cm
0.1cm
= 4 x 1010 ohm-cm
AV
5 6
VOLTAGE, kV
Figure 1-10. In situ V-l resistivity measurements.
133
-------
Flue-gas
sample
Wall of flue
Heated
sampling probe
SO3 condenser
Vent
Pump
absorber /
(peroxide-water
solution)
Flow
meter
\ Drierite
or
cold trap
Figure 1-11. Schematic Diagram of Apparatus for Collection
of SO3 by the Condensation Method
134
-------
of a helical condensation tube made from Pyrex tubing with an
internal diameter of about 7 mm and an overall length of about
1 m; a spray trap consisting of a fritted-glass filter (sealed
to the helix near the exit); a heated bath of ethylene glycol
and water around the helix and filter; and a steel pipe fitted
with an external heating tape for containing and heating the
water-glycol mixture. The S02 scrubber is a bubbler filled with
a 3% solution of H202 in water. The flow-rate indicator is a
Charcoal Test Meter (product of American Meter Company) with
an inlet filter of Drierite or, as an alternative, a vapor trap
immersed in an ice bath. The Charcoal Test Meter registers the
integral of flow rate with time and, thus, shows the total volume
of dry flue gases sampled except for the relatively small volumes
of S03 and S02 collected upstream. A small vacuum pump (Model
1031-V102-351 of Cast Manufacturing Corporation) is used for
sampling flue gases at an approximate rate of 2 1/min for a
period of about 20 min.
A titration method was used for determination of S03 and
S02 collected as H2S04. The method is based on titration of
H2S04 with Ba(C104)2, with 4:1 mixture of isopropanol and water
as the solvent and the organic dye thorin as the indicator of
the end point. This titration method is sufficiently sensitive
for use in determining S03 in flue gases at concentration down
to 1 ppm with samples of reasonable volumes ( 40 liters). It
is also sufficiently sensitive in determining the characteristi-
cally much higher concentrations of S02.
Water vapor content of the flue gas was determined with the
use of an efficient drying agent in solid form. Experimental data
obtained in the laboratory with simulated flue gas mixtures (under
past EPA contracts) showed high efficiency of water vapor recovery
and indicated that an accurate determination of water vapor con-
centration could be made with Drierite in the presence of other
flue gas components.
SAMPLE CALCULATION FOR DATA REDUCTION OF GAS ANALYSIS MEASUREMENTS
After performing the necessary sampling, the data in Table
1-4 is used to calculate S02 and S03 concentration and moisture
content of the flue gas.
1. Volume of gas sampled at STP (0°C, 760 mm Hg) = V
s
135
-------
TABLE 1-4
SOV DATA
X
Meter Temperature:
Sample Line Pressure Drop:
Gas Meter Start:
Gas Meter End:
Total Sample, Vm:
Start Sample Time:
End Sample Time:
Total Sample Time:
75°F (24°C)
119 mmHg
Barometric Pressure:
Flue Gas Temperature:
Condenser Temperature
659 mmHg
640°F (330°C)
5°C
61.6 ft3
63.9 ft3
~271 ft3
11:00
11:30
30 minutes
H2O DATA
Weight of Drierite Column, before:
Weight of Drierite Column, after:
Total Weight of H2O
Time:
Flue Gas Temperature:
Sample Line Pressure
Gas Meter Temperature:
55.0309 g
55.3726 g
.3417 g
2:30 p.m.
640°F (338°C)
33.5 mmHg
76°F (24°C)
Gas Meter Start
Gas Meter Stop:
Total Sample, Vm
72.84 ft3
73.04 ft3
.20 ft3
LAB DATA
Volume of Final Sample
Aliquot Taken
Net Titration Volume
SO 2
200 ml
2 ml
4.11 ml
SO 3
50 ml
50 ml
0.97 ml
-------
V = V x
3 m std m
v 659-119 273
x - x 273+24
= 42.5 £
where:
V = volume of gas sample at STP, liters.
o
V = volume of gas sample through the dry gas meter (meter
conditions), ft3.
P. = barometric pressure, mm Hg.
P = meter pressure, mm Hg.
P , = absolute pressure at standard conditions, 760 mm Hg.
T d = absolute temperature at STP, 273°C.
T = dry gas meter temperature, °K.
1 ft3 = 28.3 liters at STP.
2. Concentration of S02 or S03, ppm = C
TXN x 11.2 ml/meg x 10 3 yil/ml x F
SOx V
s
where:
CSOx = concentration of SO2 or S03 in parts per million.
T = titration volume of Ba(C10i»)2 solution, ml.
N = normality of Ba (ClCMa solution, milliequivalent/
milliliter .
1 milliquivalent = 11.2 milliliters at STP
1 milliliter = 103 microliters (yl)
137
-------
F = volume of sample/volume of aliquiot taken.
V = volume of gas sample at STP, liters.
o
and from Table 1-4,
4.11 ml x 5.3 x 10~3 meg/ml x 11.2 ml/meg x 103 pi/ml x 200/2
LS02 42.5 1
CSQ2 = 574 ul/1 (ppm)
and
c _ 0.97 ml x 5.3 x 10~3 meg/ml x 11.2 ml/meg x 10 3 yl/ml x 50/50
^S03 42.5 1
CS03 =1.4 yl/1 (ppm)
In order to determine the moisture content of the flue gas, the
weight of water must be converted to a vapor volume at STP and
divided by the volume of gas sample plus the vapor volume.
Therefore:
3' Vwstd = MH2Q x 1.24 1/g H20
= .3417g x 1.24 1/g H20 = 0.42
= 0.42 1
where :
Vw , = volume of water vapor in the gas sample (0°C, 760
mm Hg) , liters .
1.24 1/g H20 = 22.4 I/mole/. 18g/mole of H20 at 0°C and 760 mm Hg.
4.
Vmstd = Vm x 28.3 I/ft3 x -|5El!j» x
std m
= .20 ft3 x 28.3 I/ft3 x 65*"o3'5 x
= 4.28 1
138
-------
and
5. Moisture Content = B
wo
B - Std
WO
.42 1
B
wo 4.28 1 + .42 1
= .089 or 8.9%
Five-Stage Series Cyclone System
A five-stage series cyclone system7 which was designed and
fabricated by Southern Research Institute under EPA Contract
No. 68-02-2131 (Figure 1-12) was used at the inlet and outlet
sampling locations sequentially to obtain size fractionated
particulate for elemental analysis. The series cyclone system
was used since it satisfied the specific objectives of achieving
larger sampling times in high grain loading situations than may
be possible with an impactor, and collecting gram quantities
of size fractionated particulate for chemical analysis.
After size fractionated samples were obtained, they were
sent to Crocker Nuclear Laboratory for ion-excited X-ray analysis.8
When they were received by Crocker Nuclear Laboratory, they were
deposited upon a suitable filter material and an elemental analy-
sis determined for each.
SAMPLE CALCULATIONS FOR DATA REDUCTION OF FIVE-STAGE SERIES CYCLONE
MEASUREMENTS
The data reduction technique for the cyclones follows that
of the impactor data reduction as previously outlined with the
major difference being the calculation of the D50 cut point for
each cyclone.
7. Smith, Wallace B. and Rufus R. Wilson, Jr. Development and
Laboratory Evaluation of a Five-Stage Cyclone System. EPA-600/
7-78-008, January, 1978.
8. Cahill, T.A., e_t al. Monitoring of Smog Aerosols with
Elemental Analysis by Accelerator Beams. National Bureau
of Standards, Special Publication 422, issued August, 1976.
139
-------
CYCLONE 1
CYCLONE 4
CYCLONE 5
CYCLONE 2
CYCLONE 3
OUTLET
INLET NOZZLE
3630-240
Figure 1-12. Southern Research Institute Five Series Cyclone System.
140
-------
The following is a description of the procedure used in cal-
culating the D50 cutpoints for the cyclones which were operated
at the Navajo Generating Station under the conditions stated
in Table 19 of the text.
It is assumed that changes in viscosity (temperature), flow-
rate, and particle density are independent of each other in
affecting cyclone performance. Thus, adjustments can be made
in each of these separately of the other.
Example Calculation; Cyclone 1 D5o for Run ID CYC 3
From Figure 1-13, the D50-viscosity line is extrapolated to
obtain 8.18 ym for the D50 of cyclone 1 at a temperature of 685°F,
a particle density of 2.04 g/cnr, and a flowrate of 1 ft3/min.
The density of the dust collected was 2.41 g/cm3. The D50 varies
inversely with the square root of the density for cyclones, thus:
DSQ (p=2.41 g/cm3)
Dso (p=2.04 g/cm3)
(1)
Since Dso for a particle density of 2.04 g/cm3 is 8.18 pm, the D
of cyclone 1 for a particle density of 2.41 g/cm3, a temperature
5 0
685°F, and a flowrate of 1 ft3/min is 7.53 pm.
dependence for cyclone 1 is assumed to be
The D50 flowrate
Dso = KQ
n
(2)
where Q is flowrate in liters/min and K and n are experimental
constants.
Dividing equation (2) by itself, for the two flow rate, we
obtain
D50(2.41 g/cm3, 685°F, 1.07 ft3/min) _ (30.30)
D50(2.41 g/cm3, 685°F, 1.00 ft3/min) (28.32)
(3)
where n = -.63 is an experimental value found in our laboratory
calibration of cyclone 1. Equation (3) gives 7.21 ym for the
D
5 0
of cyclone 1 for a particle density of 2.41 g/cm3, a tempera-
ture 685°F, and a flowrate of 1.07 ft3/min.
141
-------
25
2
u
1
g
O
180
TEMPERATURE, degrees C
204
316
220 260
VISCOSITY, micropoise
300
Figure 1-13. D^Q cut point versus viscosity for EPA-S.R.I. Cyclones I, II,
and III at a flow rate of 28.3 t/min, temperatures of 25, 93,
and 204°C, and for a particle density of 2.04 gm/crrt^.
142
-------
Cyclone 1 Dgn for Run IDC CYC 5
From Figure 1-13, an extrapolation of the D50-viscosity
curve gives 7.83 ym for the D50 of cyclone 1 for a temperature
of 630°F, a particle density of 2.04 g/cm3, and a flowrate of
1 ft3/min. Equation (1) then becomes
D50(p=2.41 g/cm3) _
7.83 ym
giving 7.20 ym for the D50 of cyclone 1 for a temperature of
630°F, a particle density of 2.41 g/cm3, and a flowrate of 1
ft3/min. Finally, equation (3) becomes
D50(2.41 g/cm3, 630°Fy 1.1 ft3/min = (31.15)"-63
7.20 ym (28.32)~'63
giving 6.78 ym for the D50 of cyclone 1 for a temperature of
630°F, a particle density of 2.41 g/cm3, and a flowrate of 1.1
ftVmin.
Cyclone 1 Dsn for Run ID CYC 7
From Figure 1-13, an extrapolation of the D50-viscosity
curve gives 8.27 ym for the D50 of cyclone 1 for a temperature
of 700°F, a particle density of 2.04 g/cm3, and a flowrate of
1 ft3/min. Equation (1) then becomes
D50(p=2.41 g/cm3)
8.27 ym
giving 7.61 ym for the D50 of cyclone 1 for a temperature of
700°F, a particle density of 2.41 g/cm3, and a flowrate of 1
ft3/min. Finally, equation (3) becomes
D50(2.41 g/cm3, 700°F, 1.2 ft3/min = (34.55)~-63
7.61 ym (28.32)~'63
giving 6.78 ym for the D50 of.cyclone 1 for a temperature of
700°F, a particle density of 2.41 g/cm3, and a flowrate of 1.2
ft3/min. The D50's for cyclone 2 and 3 are calculated exactly
like the D50's for cyclone 1 but using the appropriate curve from
Figure 1-13 and using n = -.70 for cyclone 2 and n = -.84 for
cyclone 3.
143
-------
Cyclones 4 and 5 were calibrated at only one temperature
because of experimental limitations. However, the D50-viscosity
dependence was assumed to be linear for both of them. From the
D50-viscosity curves for cyclones 2 and 3 it was noticed that
the D50's at 400°F were approximately twice those at 77°F. Cy-
clones 4 and 5 were assumed to have similar behavior, that is,
that their D50's at a temperature of 400°F would be twice those
at 77°F.
The Dso's of cyclones 4 and 5 were estimated for a particle
density of 2.04 g/cm3, as follows:
Dsn(77°F, 2.04 g/cm3, 1 ft3/min) = 1.05
D50(77°F, 1.05 g/cm3, 1 ft3/min) " 2.04
From Table 1-5 (Table 3, p. 36, EPA report #EPA-600/7/78-008),
ni
2.04 g/cm3.
for cyclone 4, the D50 is 0.64 ym at 1.05 g/cm3 and 0.46 ym at
For cyclone 5, the D50 is 0.32 ym at 1.05 g/cm3 and 0.23
ym at 2.04 g/cm3.
Therefore, the D5„ of cyclone 4 is 0.46 ym at 77°F, 2.04
g/cm3, and 1 ft3/min and 0.92 ym (2x0.46) at 400°F, 2.04 g/cm3,
and 1 ft3/min. These points were plotted on the grid in Fig-
ure 1-13 and a line was drawn through them and extrapolated to
700°F. Likewise, the D50 of cyclone 5 is 0.23 ym at 77°F, 2.04
g/cm3, and 1 ft3/min, and 0.46 ym (2x0.23) at 400°F, 2.04 g/cm3,
and 1 ft3/min. These points were plotted on the grid in Fig-
ure 1-13 and a line was drawn through them and extrapolated to
700°F. After the D50-viscosity curves for cyclones 4 and 5 were
plotted, the same procedure for estimating the D50's of cyclones
1, 2, and 3 could be utilized. Table 1-6 shows the D50's of
each of the cyclones at each step of the procedure for all three
runs.
Secondary Voltage-Current Measurements
Calibrated voltage divider resistor assemblies were attached
to the high voltage bus-bar of each transformer rectifier which
powered chambers 7 and 8 of the Unit #3 precipitator. Secondary
voltage vs. current curves were obtained for each TR beginning
with the "C" or 6th field and progressing to the "H" or 1st field.
The correct secondary voltage was obtained by multiplying
the correction factor of the voltage divider times the reading
of the volt-Ohm-meter.
144
-------
TABLE 1-5
LABORATORY CALIBRATION OF THE FIVE-STAGE CYCLONES
Cut Points
Cyclone
Particle Density (gm/cm3)
Flow
7.1
14.2
28.3
28.3
28.3
Temperature
°C
25
25
25
93
204
2.04 1.00
II
2.04 1.00
III
2.04 1.35 1.00
Cyclone Dso cut points
micrometers
5.9
3.8
4.4
6.4
(8.4)
(5.4)
(6.3)
(9.1)
2.4
1.5
2.3
2.9
(3.5)
(2.1)
(3.3)
(4.1)
(1.7) 2.1
.95
1.2
1.9
(2.4)
(1.4)
(1.8)
(2.8)
IV
1.05 1.00
V
2.5 (2.5)
1.5 (1.5)
.64 (.65)
1.05
1.00
1.5 (1.5)
.85 (.87)
.32 (.32)
Ul
cut points enclosed in parentheses are derived from the experimental data using Stoke's law.
-------
TABLE 1-6
STEPS IN PROCEDURE USED TO ESTIMATE CYCLONE D50's
FOR TESTS AT
NAVAJO GENERATING STATION, PAGE, ARIZONA
Run Number Cyclone
CYC 3
CYC 5
CYC 7
I
II
III
IV
V
I
II
III
IV
V
I
II
III
IV
V
At Calibration
Conditions
1
2
cfm
400°
F
.04 g/cm3
6
2
1
6
2
1
6
2
1
.39
.89
.94
.46
.23
. 39
.89
.94
.46
.23
.39
.89
.94
.46
.23
At Adjusted
Temperature
1 cfm,
2.04 g/cm3
°F Dso
685
685
685
685
685
630
630
630
630
630
700
700
700
700
700
8. 13
3.95
2. 62
1.41
.58
7.83
3.78
2.49
1.16
.56
8.27
4.00
2. 66
1.24
.59
At Adjusted
Density
1 cfm,
2.41 g/cm3
Dso
At Adjusted
Flowrate
2.41 g/cm3
cfm
D
s o
7.53
3.64
2.41
1.30
.534
7.20
3.47
2.29
1.07
.515
7.61
3. 68
2.44
1.14
.543
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
1.
07
07
07
07
07
1
1
1
1
1
2
2
2
2
2
7.
3.
2.
1.
•
6.
3.
2.
•
•
6.
3.
2.
w
•
2
5
3
2
50
8
2
1
96
46
8
2
1
96
45
-------
APPENDIX 2
IMPACTOR SUBSTRATE WEIGHT CHANGES FOR BLANK RUNS
147
-------
£>•
CO
Table 2-1
Inlet Blanks Navajo Generating Station
Run Number
Date
SO (mg)
SI (mg)
S2 (mg)
S3 (mg)
S4 (mg)
S5 (mg)
S6 (mg)
SF (mg)
NGSI-3
7/12/7
0.32*
0.13*
0.10*
0.11*
0.13*
0.08*
0.07*
0.09*
NGSI-5
7/13/77
0.05*
0.02*
0.04*
1.03*
0.30*
0.01*
-
0.02*
NGSI-10
7/14/77
0.07
0.10
0.06
0.06
0.06
0.07
-
0.09
NGSI-14
7/15/77
0.08
0.10*
0.08*
0.10
0.09
0.15*
-
0.15
NGSI-18
7/16/77
0.11*
0.08*
0.10*
0.23
0.09
0.09
-
0.15
NGSI-22
7/18/77
0.04
0.03
0 06
0.04
0.03
0.01
-
0.08
NGSI-26
7/19/77
-0.03*
-0.05*
0.01*
-0.05*
-0.07*
-0.05*
-
0.23*
NGSI-29
7/20/77
0.02
0.05
0.03
0.07
0.13
0.03*
-
0.13
NGSI-33
7/21/77
0.92*
-0.13*
-0.69*
0.06
0.06
0.01
-
0.09
NGSI-52
8/2/77
0.03
0.00
0.00
0.00
0.00
0.00
0.10
NGSI-55
8/3/77
0.06*
0.11*
0.07*
0 . 10*
0.18*
0.49*
0.06*
0.15*
NGSI-6
8/4/77
-0.02
0.00
0.00
0.00
-0.04*
-0.04*
-0.03*
0.14
i *not used in average because of copper chips or particulate detected on stage when impactor was
unloaded, or test for outlier excluded stage weight.
ii. SO-S6 average together for all Brink stage runs in a test series
iii. SF average together for all Brink back-up filters in a test series
-------
Table 2-2
Outlet Blanks Navajo Generating Station
Run Number
Date
Nozzle (mg)
SI
S2
S3
S4
S5
S6
S7
S8
SF
(mg)
(mg)
(mg)
(mg)
(mg)
(mg)
(mg)
(mg)
(mg)
NGSO-3B
7/12/77
2.67
-0.26
-0.13
0.03
-0.32
-0.30
-0.56*
-0.06
-0.22
0.46
NGSO-4B
7/13/77
3.97
-0.13
-0.25
0.07
-0.31
-0.08
0.03
-0.03
-0.22
-0.07
NGSO-11B NGSO-14B NGSO-20B NGSO-28B NGSO-33B NGSO-36B NGSO-40B
7/14/77
1.95
0.00
-0.03
-0 . .'9
-O.x2
0.00
-0.06
-0.06
-0.09
0.24
7/15/77
2.39
-0.26
-0.15
0.38*
-0.10
-0.11
-0.20
0.18
-0.06
0.01
7/16/77
1.35
0.15
0.06
0 .04
-0.07
-0.02
-0.10
-0.03
-0.10
0.24
7/18/77
0.42
-0.08
0.33*
0.04
0.12
0.01
0.33*
0.04
0.34*
0.03
7/19/77
0.33
-0.84*
-1.11*
-0.22
-1.46*
-n 36
-0.88*
-0.60*
-0.30
-0.02
7/20/77
0.30
0.40*
-0.49
0.11
-0.46
-0.13
-0.29
-0.36
-0.36
2.55*
7/21/77
1.06
-0.44
-0.20
-0.23
0.03
-0.47
-0.15
-0.51*
-0.74*
0.19
NGSO-54
8/2/77
11.35
0.11*
0.03*
0.04*
0.04*
0.06*
-0.06*
0.04*
-0.10*
0.06
NGSO-55 NGSO-58
8/3/77
9.12
0.41
0.56
0.19
0.25
0.32
0.07
0.13
0.27
0.21
8/4/77
10.97
0.25
0.17
0.08
0.72
0.06
0.61
0.22
0.77
0.13
vo
i. *not used in average because of filter being torn, particulate matter on stage, or outlier test
excluded stage weight.
ii. nozzle average together for all runs in a test series
iii. S1-S8 average together for all runs in a test series
iv. SF average together for all runs in a test series
v. SI correction factor is SI , ± SI. , , ± Nozzle n ± Nozzle, .. ,
real blank real blank
-------
APPENDIX 3
VOLTAGE - CURRENT DATA
150
-------
01
2
U
\
01
CL
2
a
z
o
H
H
01
UJ
a
h-
z
LJ
rv
rv
D
U
BOoO-
75.0-
70.0-
65.0-
55.0-
50.0-
45.0-
40.0-
35.0-
3D.O-
25.0-
20.0-
15.0-
10.0-
5.0-
0.0-
V l_JI | / \l_Jl_ l^l_Jl M M — 1 M 1 I^LJ! \ V I_^J
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VOLTAGE.KV
All Fields July 13-14, 1977
151
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VOLTAGE-CURRENT CURVES
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July 14-15, 1977
152
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July 15-16, 1977
153
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July 16-17, 1977
154
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VOLTAGE.KV
July 21-22, 1977
155
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/14/77, 'H' Field
Primary
Voltage Current
V
158
170
180
25
50
75
Spark
Rate
Sparks/
min
25
150
320
Secondary
Voltage Current
KV
28
29
29
MA
100
200
300
Corrected
Secondary
Voltage
KV
26.2
26.8
26.2
Current
Density
nA/
cm2
4.3
8.5
13.7
Chambers 7 & 8, 7/14/77, 'G1 Field
140
162
175
180
190
195
20
48
65
84
110
125
--
—
25
75
200
350
24
25.2
26
26.5
26.8
26.5
100
200
300
400
500
600
22.9
24.1
24.9
25.1
25.4
25.5
4.3
8.5
12.8
17.1
21.4
25.6
Chambers 7 & 8, 7/14/77, 'F1 Field
130
140
152
165
172
180
185
190
20
50
68
85
105
125
145
160
--
--
—
—
—
25
250
350
20.2
21.2
21.8
22
22.5
22.5
23
23
100
200
300
400
500
600
700
800
19.3
20.0
20.7
20.8
21.1
21.4
21.7
21.7
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
156
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/14/77, 'E' Field
Primary
Voltage Current
V A
85
130
140
150
155
157
170
175
185
185
--
20
50
67
80
105
125
140
160
175
Spark
Rate
Sparks/
min
Secondary
Voltage Current
100
200
KV
MA
19
22.5
23
23.5
23.5
23.5
24
24
24
24
—
100
200
300
400
500
600
700
800
900
Corrected
Secondary
Voltage
KV
16,
20,
20,
20,
20.6
20.8
20.9
21.1
21.3
21.1
,7
,2
,4
,5
Current
Density
nA/
cm2
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
Chambers 7 & 8, 7/14/77, 'D1 Field
110
135
140
148
150
154
160
165
170
20
65
95
112
133
150
167
185
200
--
—
—
—
--
25
50
300
50
20.3
20.7
21
21.5
21.3
21.4
21
21.5
21.5
—
100
200
300
400
500
600
700
800
18.6
19.0
19.2
19.3
19.4
19.4
19.3
19.5
19.3
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
157
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/14/77, 'C' Field
Primary
Voltage Current
V A
Spark
Rate
Sparks/
min
Secondary
Voltage Current
KV
MA
Corrected
Secondary
Voltage
KV
100
110
115
135
140
145
150
155
160
164
165
175
—
20
55
87
110
128
157
183
195
210
228
250
—
—
—
—
—
—
—
—
50
100
100
250
18.4
19.7
20
20.2
20.4
20.5
20.5
20.7
20.8
20.6
21
21.5
40
150
250
400
500
600
750
900
1000
1100
1200
1300
15.8
16.9
17.2
17.6
17.7
17.7
17.7
17.8
18.0
17.8
17.9
18.1
Current
Density
nA/
cm2
1.7
6.4
10.7
17.1
21.4
25.6
32.0
38.4
42.7
47.0
51.3
55.5
158
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/15/77, 'H1 Field
Primary
Voltage Current
V A
Spark
Rate
Sparks/
min
Secondary
Voltage Current
KV
MA
100
160
175
185
—
25
50
70
—
—
100
250
21.5
28.5
29.5
30
--
100
200
300
Corrected
Secondary
Voltage
KV
20.8
26.6
27.4
27.4
Current
Density
nA/
cm2
4.3
8.5
12.8
Chambers 7 & 8, 7/15/77, 'G1 Field
100
150
160
175
185
195
200
205
--
25
45
65
85
105
125
140
—
—
—
—
--
—
200
300
21
25
26
26.5
27
27.5
27.5
28
--
100
200
300
400
500
600
700
20.2
23.9
24.6
25.2
25.5
25.7
26.0
26.1
4.3
8.5
12.8
17.1
21.4
25.6
29.9
Chambers 7 & 8, 7/15/77, 'F1 Field
75
150
165
175
185
200
200
—
20
40
62
80
105
125
—
—
—
25
125
200
200
18
25
26
26.4
26.8
27.5
27
—
100
200
300
400
500
600
22.5
22.6
22.7
22.5
22.7
22.5
22.3
4.3
8.5
12.8
17.1
21.4
25.6
159
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7715/77, 'E1 Field
Primary
Voltage Current
V A
Spark Secondary
Rate Voltage Current
Sparks/
min
KV
100
130
145
150
155
165
168
175
178
185
Chambers
127 .
137
142
148
150
155
160
166
170
174
175
—
25
50
70
80
105
120
135
160
175
7 & 8,
50
72
92
113
132
148
165
185
200
220
232
--
—
—
—
—
—
25
—
50
250
7/15/77,
__
—
—
—
—
25
—
100
200
150
150
20
23
23.5
24
24
24.5
24
24
24.5
25
'D' Field
20.2
20.6
21
21.3
21.5
21.7
21.5
22
21.7
22
21.7
MA
Corrected
Secondary
Voltage
KV
20
23
23.
24
24
24.
24
24
24.
25
5
5
5
—
100
200
300
400
500
600
700
800
900
18.3
20.3
20.8
21.2
21.3
21.5
21.1
21.4
21.3
21.4
20.2
20.6
21
21.3
21.5
21.7
21.5
22
21.7
22
21.7
--
100
200
300
400
500
600
700
800
900
1000
18
18
18
19
19
19
19
19
19
19
19
.3
.7
.9
.1
.3
.6
.6
.7
.7
. 7
.7
Current
Density
nA/
cm2
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
160
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/15/77, 'C' Field
Primary
Voltage Current
V A
Spark
Rate
Sparks/
min
Secondary
Voltage Current
KV
MA
Corrected
Secondary
Voltage
KV
100
120
130
140
145
148
153
160
165
170
173
177
—
—
45
70
90
108
130
158
184
200
210
235
—
—
—
—
—
—
—
20
30
40
100
250
18
20
20.5
20.6
21.2
21.2
21.3
21.5
21.5
21.6
21.8
22
—
100
200
300
400
500
600
750
900
1000
1100
1250
15.4
17.0
17.4
17.7
18.0
18.1
18.2
18.3
18.4
18.6
18.7
18.6
Current
Density
nA/
cm2
4.3
8.5
12.8
17.1
21.4
25.6
32.0
38.4
42.7
47.0
53.4
161
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/16/77, 'H' Field
Primary
Voltage Current
V A
Spark
Rate
Sparks/
min
Secondary
Voltage Current
KV
MA
Corrected
Secondary
Voltage
KV
Current
Density
nA/
cm2
20
160
172
180
185
190
—
20
50
59
70
85
—
—
50
25
150
175
15
28.5
29.5
29.7
30
31
--
100
200
250
300
350
14.0
26. 6
27.8
27.3
28.1
28.0
4.3
8.5
10.7
12.8
15.0
Chambers 7 & 8, 7/16/77, 'G1 Field
50
150
165
178
185
190
20
40
67
85
100
25
150
250
15
25
26.4
26.5
27.5
27.4
100
200
300
400
480
15.3
24.0
25.0
25.3
25.8
26.1
4.3
8.5
12.8
17.1
20 .5
162
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/16/77, 'F1 Field
Primary
Voltage Current
V A
Spark Secondary
Rate Voltage Current
Sparks/
min
KV
MA
117
140
155
165
170
175
185
190
195
200
20
25
50
70
88
107
128
140
160
175
--
—
—
—
25
—
75
100
150
250
19.5
22
22.8
23
23.2
23
23.4
23
23.3
23.5
—
100
200
300
400
500
600
700
800
900
Corrected
Secondary
Voltage
KV
18.3
20.5
21.5
22.0
21.8
21.8
22.1
22.1
22.0
22.1
Current
Density
nA/
cm2
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
Chambers 7 & 8, 7/16/77, 'E1 Field
90
130
145
150
160
165
178
175
178
180
--
25
50
65
80
110
125
140
155
175
—
--
—
—
—
25
50
50
100
300
20
23
23.8
24
24.5
24
24
24
24
24
—
100
200
300
400
500
600
700
800
900
17.5
20.4
21.1
20.9
21.2
20.8
21.4
20.8
20.7
21.1
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
163
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/16/77, 'D1 Field
Primary
Voltage
V
130
90
145
150
153
158
163
165
172
172
Chambers
110
122
130
140
144
148
152
154
157
162
162
170
172
180
Spark
Se
Current Rate Voltag
A
50
72
95
110
132
150
168
185
205
218
7 & 8,
—
20
40
78
88
108
128
148
163
183
195
225
240
255
Sparks/
min
—
—
—
—
20
50
100
100
150
250
7/16/77, 'C'
—
—
—
—
--
—
—
—
—
—
—
—
100
50-250
KV
20.5
21.2
21.6
22
22.2
22.3
22
22.2
22.5
22.5
Field
19
20.4
20.5
20.8
20.8
21
21
21
20.5
20.5
20.5
21
21.5
21.7
Secondary
Current
MA
100
200
300
300
500
600
700
800
900
Corrected
Secondary
Voltage
KV
18.4
19.2
19.5
19.6
19.8
19.8
19.9
20.0
20.0
19.8
19
20.4
20.5
20.8
20.8
21
21
21
20.5
20.5
20.5
21
21.5
21.7
25
100
200
300
400
500
600
700
800
900
1000
1200
1300
1400
16
17
17
17
17
17
17
17
17
17
17
17
18
18
.4
.5
.6
.8
.7
.8
.6
.5
.4
.5
.5
.7
.0
.3
Current
Density
nA/
cm2
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
1.1
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
51.3
55.5
59.8
164
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/17/77, 'H1 Field
Primary
Voltage Current
V A
Spark
Rate
Sparks/
min
Secondary
Voltage Current
KV
MA
Corrected
Secondary
Voltage
KV
Current
Density
nA/
cm2
100
160
172
190
195
—
25
50
70
100
—
—
50
100
300
21
29
29.5
30.4
30
—
100
200
300
400
19.8
26.6
27.2
27.5
26.8
4.3
8.5
12.8
17.1
Chambers 7 & 8, 7/17/77, 'G1 Field
50
145
160
170
180
185
190
—
20
50
65
85
95
110
--
—
—
50
100
150
200
17
24.5
25.3
26
26.5
26.5
27
—
100
200
300
400
450
500
16.3
23.1
24.2
24.7
25.0
25.0
25.0
4.3
8.5
12.8
17.1
19.2
21.4
165
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/17/77, 'F1 Field
Primary
Voltage Current
V A
Spark Secondary
Rate Voltage Current
Sparks/
min
KV
MA
Corrected
Secondary
Voltage
KV
Current
Density
nA/
cm2
105
135
150
160
165
175
180
188
196
200
205
--
20
50
70
75
108
123
140
157
170
180
--
—
—
—
—
—
25
—
100
150
300
19.5
21.5
22.5
22.6
22.8
23
23.5
23
23.5
23.5
24
--
100
200
300
400
500
600
700
800
900
1000
17.9
20.1
20.8
21.2
21.3
21.7
21.7
21.8
22.0
22.1
22.0
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
Chambers 7 & 8, 7/17/77, 'E1 Field
100
130
140
150
160
165
170
175
180
165
190
—
20
48
70
80
105
125
145
155
175
180
—
—
20
—
—
—
25
50
100
250
20
23
23.
23.
24
24
24
24
24.
25
25
8
9
5
—
100
200
300
400
500
600
700
800
900
1000
17.3
19.9
20.3
20.4
20.7
20.8
20.8
20.8
20.9
21.0
21.2
166
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/17/77, 'D1 Field
Primary
Voltage Current
V A
120
138
145
150
152
157
162
163
170
173
175
20
75
95
115
132
150
167
182
200
218
228
Spark
Rate
Sparks/
min
Secondary
Voltage Current
25
50
100
0-500
KV
MA
Corrected
Secondary
Voltage
KV
20
21.4
21.8
22
22.3
22.2
22
21.8
22.2
22.5
22
—
100
200
300
400
500
600
700
800
900
1000
16.0
17.0
17.4
17.8
18.0
18.1
18.3
18.3
18.6
18.8
18.9
Current
Density
nA/
cm2
43.
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
Chambers 7 & 8, 7/17/77, 'C' Field
65
125
132
135
140
145
148
153
155
158
164
166
170
170
20
50
70
88
110
128
148
165
182
200
215
228
245
200
--
20
20.4
20.8
21
21
20.8
20.7
20.5
20.4
20.6
20.6
21
21
—
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
13.9
16.9
17.1
17.4
17.5
17.5
17.4
17.2
17.2
17.1
17.2
17.2
17.3
17.4
4.3
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
47.0
51.3
55.5
167
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/22/77, 'H1 Field
Primary
Voltage Current
V A
50
148
165
175
180
184
—
20
25
40
50
57
Chambers 7 & 8,
50
140
155
165
172
179
190
—
10
25
28
48
55
70
190
73
Spark
t Rate
Sparks/
min
—
--
—
20-50
100-250
7/22/77. 'G'
—
—
—
20-50
30-75
250
200-400
Se
yoltag
KV
16
28.5
30.3
30.5
31
31.5
Field
16
25.2
26.3
27
27.5
28
28.5
28.5
Secondary
Current
MA
50
100
150
200
240
50
100
150
200
250
300
350
Corrected
Secondary
Voltage
KV
14.2
25.9
28.0
28.1
28.6
28.1
14.5
23.8
24.8
25.3
26.0
26.3
26.4
26.2
Current
Density
nA/
cm2
2.1
4.3
6.4
8.5
10.3
2.1
4.3
6.4
8.5
10.7
12.8
15.0
168
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/22/78, 'F1 Field
Primary
Voltage Current
V
120
133
145
153
163
166
170
180
189
191
200
20
25
30
35
50
58
67
87
112
125
140
Spark
Rate
Sparks/
min
Secondary
Voltage Current
10-25
50-150
25-50
100-500
KV
20
22
23.2
23.5
24
24.3
24.4
24.5
24.8
24.5
24.5
MA
50
100
150
200
250
300
400
500
600
700
Corrected
Secondary
Voltage
KV
19.2
21.0
22.1
22.4
22.5
23.0
23.0
23.2
23.3
23.2
23.5
Current
Density
nA/
cm2
2.1
4.3
6.4
8.5
10.7
12.8
17.1
21.4
25.6
29.9
169
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/22/77, 'E1 Field
Primary
Voltage
V
70
125
140
147
150
160
166
170
175
180
185
190
195
Chambers
100
140
145
148
150
150
154
160
165
170
173
180
Spark
Se
Current Rate Voltag
A
—
20
25
35
50
67
87
110
123
138
155
170
180
7 & 8,
10
65
75
87
95
105
115
132
150
170
185
200
Sparks/
min
—
--
--
—
—
--
--
—
--
20-50
50-150
150-300
50-350
7/22/77, 'D1
—
—
--
—
—
—
--
25-100
150
200-450
200-300
450
KV
20
23.5
25
25
25
25.2
25.3
25
25
25
25
25
25
Field
20
22.2
22.5
22.8
23
22.6
23
23
22.8
23
22.6
22.7
Secondary
Current
MA
50
100
150
200
300
400
500
600
700
800
900
1000
50
100
150
200
250
300
400
500
600
700
800
Corrected
Secondary
Voltage
KV
17.3
20.5
21.4
21.6
21.6
21.6
21.6
21.6
21.4
21.4
21.4
21.7
21.7
17.6
19.8
19.9
20
20
20
20
20
20
20
20,
,1
,4
,1
,2
,5
2
,5
1
Current
Density
nA/
cm2
2.1
4.3
6.4
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
20.0
2.1
4.3
6.4
8.5
10. 7
12.8
17.1
21.4
25.6
29.9
34.2
170
-------
Panel meter readings obtained for voltage-current curves
and corrected secondary voltages as measured with voltage dividers
Chambers 7 & 8, 7/22/77, 'C1 Field
Primary
Voltage Current
V A
Spark Secondary
Rate Voltage Current
Sparks/
min
KV
MA
Corrected
Secondary
Voltage
KV
Current
Density
nA/
cm2
100
120
128
133
138
142
148
150
155
160
162
168
170
173
178
10
15
25
50
70
87
108
132
150
163
185
200
214
230
--
—
—
—
--
--
—
—
—
10-20
25-30
25-75
25-100
100
250-500
18
21
21.2
21.4
21.5
21.7
21.5
21.5
21.5
21.4
21.3
21.6
21.5
21.6
22.5
25
50
100
150
200
300
400
500
600
700
800
900
1000
1100
1200
16.0
17.3
17.7
17.9
18.0
18.2
18.0
18.0
18.0
17.9
17.8
17.8
18.0
18.1
18.3
1.1
2.1
4.3
6.4
8.5
12.8
17.1
21.4
25.6
29.9
34.2
38.4
42.7
47.0
51.3
171
-------
Date: 8/1-2/77
Chambers 1 & 2
Navajo Generating Station
Unit #3
Voltage Current Readings
Time:
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
DC KV
31
30.5
25.2
23
22.3
22.3
3 & 4
DC KV
31.8
31
26.5
23.5
22
20.5
5 & 6
DC KV
30
30
27
25
22. 5
21. 5
7 & 8
FIELD DC KV
H
G
F
E
D
C
30
26.5
22.5
23. 5
21. 0
21
ACV
200
195
205
182
190
185
ACV
195
210
200
190
190
180
ACV
180
200
175
180
180
170
ACV
190
205
200
190
175
175
SPARK
25
40
20
10
60
35
SPARK
50
75
50
25
35
20
SPARK
20
75
60
45
25
30
SPARK
35
45
20
20
15
15
ACA
65
145
195
180
240
248
ACA
95
130
190
195
240
240
ACA
50
65
70
95
160
180
ACA
100
140
198
200
250
250
DCMA
200
660
1100
1000
1400
1430
DCMA
340
620
1020
1080
1320
1300
DCMA
200
280
360
440
850
910
DCMA
360
740
1060
1050
1135
1400
03:00
Chambers
FIELD
H
G
F
E
D
C
DC
30
32
25.
24
23.
21.
Chambers
FIELD
H
G
F
E
D
C
DC
30.
31.
27
25.
22.
21.
Chambers
FIELD
H
G
F
E
D
C
DC
31
33
27.
24.
23
22.
Chambers
FIELD
H
G
F
E
D
C
DC
30.
31
26
24
23.
22
9 & 10
KV
5
5
5
11
KV
5
75
5
5
5
13
KV
5
5
25
15
KV
5
5
ACV
190
220
200
200
190
180
& 12
ACV
190
225
210
205
200
185
& 14
ACV
200
220
205
200
190
183
& 16
ACV
200
220
200
190
190
165
SPARK
40
30
25
80
55
35
SPARK
80
65
40
10
20
10
SPARK
120
35
35
20
25
20
SPARK
35
40
35
30
45
10
ACA
40
80
180
165
245
250
ACA
35
85
160
195
250
253
ACA
40
70
160
192
247
250
ACA
35
75
183
170
248
250
DCMA
180
400
960
1020
1475
1575
DCMA
160
430
1020
1050
1420
1380
DCMA
160
320
960
980
1400
1450
DCMA
180
340
920
900
1425
1520
172
-------
Navajo Generating Station
Unit #3
Voltage Current Readings
Date:
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
8/2-3/77
1 & 2
DC KV
33.5
32
26.5
24
23.5
23
3 & 4
DC KV
34
33
28
24.5
22.5
21.5
5 & 6
DC KV
32
31.5
27.5
25
23
21.5
7 & 8
DC KV
32. 5
28.5
23.5
25
22. 5
22
ACV
205
200
210
185
195
190
ACV
195
210
205
195
190
185
ACV
185
205
190
175
180
180
ACV
190
218
210
190
178
180
SPARK
45
20
50
10
25
10
SPARK
20
50
60
50
20
30
SPARK
40
70
60
30
40
50
SPARK
30
30
50
25
15
40
ACA
50
150
185
190
250
247
ACA
70
145
175
180
242
240
ACA
40
60
80
90
165
190
ACA
55
130
165
175
235
245
Time
DCMA
200
580
1060
1000
1400
1425
DCMA
250
530
940
1100
1350
1350
DCMA
140
260
330
400
850
1000
DCMA
240
680
980
720
1100
1275
23:45
Chambers 9 & 10
FIELD
H
G
F
E
D
C
DC
32.
33.
26.
25
24.
22
Chambers
FIELD
H
G
F
E
D
C
DC
31.
33
28.
27
24.
22
Chambers
FIELD
H
G
F
E
D
C
DC
32
32.
30
26
24
23
Chambers
FIELD
H
G
F
E
D
C
DC
32.
33.
27
25.
24.
22.
KV
5
5
5
5
11
KV
5
5
5
13
KV
5
15
KV
5
5
5
0
5
ACV
200
220
210
200
195
180
& 12
ACV
195
225
215
210
205
190
& 14
ACV
200
220
200
210
195
190
& 16
ACV
200
230
200
200
195
170
SPARK
50
70
105
30
30
60
SPARK
50
50
45
30
30
20
SPARK
100
60
30
25
25
30
SPARK
40
50
50
30
10
15
ACA
30
85
175
180
250
245
ACA
30
65
135
150
250
250
ACA
30
45
140
175
240
250
ACA
30
70
170
190
245
250
DCMA
150
410
930
1030
1500
1450
DCMA
140
340
710
900
1400
1350
DCMA
140
200
720
940
1350
1450
DCMA
130
315
900
1000
1400
1500
173
-------
Date: 8/2-3/77
Chambers 1 & 2
Navajo Generating Station
Unit #3
Voltage Current Readings
Time: 02:00
Chambers 9 & 10
Field
H
G
F
E
D
C
Chambers
Field
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
DC KV
33.5
32
26
24
23
23
3 & 4
DC KV
35
33.5
27
24
22
21
5 & 6
DC KV
32
32
29
26
23
22
7 & 8
DC KV
33
29
24
25.5
33
22
ACV
205
200
200
180
190
185
ACV
210
220
195
195
190
180
ACV
180
200
200
180
180
180
ACV
200
220
210
200
180
185
SPARK
100
115
130
170
125
200
SPARK
120
160
300
170
180
200
SPARK
170
165
190
215
160
150
SPARK
100
210
180
130
300
45
ACA
70
150
160
170
220
200
ACA
75
100
140
180
230
230
ACA
40
60
90
100
170
190
ACA
65
150
185
210
240
250
DCMA
360
560
960
900
1200
1100
DCMA
260
440
640
1000
1200
1200
DCMA
130
250
420
450
900
1000
DCMA
300
740
980
1120
1000
1400
FIELD
H
G
F
E
D
C
DC
32.
34.
26
25
24
22
Chambers
FIELD
H
G
F
E
D
C
DC
32
34
29
27
23
22
*Chambers
FIELD
H
G
F
E
D
C
DC
32
35
30
26
24
23
Chambers
FIELD
H
G
F
E
D
C
DC
31.
33.
27
25
24
22.
KV
5
5
11
KV
13
KV
15
KV
5
5
5
ACV
200
230
210
210
200
180
& 12
ACV
200
240
220
210
205
190
& 14
ACV
205
235
220
210
190
190
& 16
ACV
200
230
205
180
200
170
SPARK
130
150
220
140
120
170
SPARK
130
125
160
80
40
20
SPARK
150
120
140
90
140
40
SPARK
80
80
55
210
50
30
ACA
40
100
170
170
235
255
ACA
40
100
170
190
250
250
ACA
50
75
160
195
230
250
ACA
40
110
190
150
250
250
DCMA
140
500
940
1020
1400
1380
DCMA
160
360
860
1030
1300
1450
DCMA
140
440
1060
840
1400
1500
*13 & 14 - Main heaters out
174
-------
Date: 8/2-3/77
Chambers 1 & 2
Navajo Generating Station
Unit #3
Voltage Current Readings
Time: ^04:00
Chambers 9 & 10
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
DC KV
33
32
26
23.5
23
23
3 & 4
DC KV
35
33.5
27
24
22
21
5 & 6
DC KV
31
31
28
25
23
21.5
7 & 8
DC KV
32
28
23
25
22
22
ACV
215
210
210
185
190
190
ACV
215
220
205
195
190
185
ACV
180
205
195
185
180
180
ACV
200
210
205
190
170
180
SPARK
100
90
80
140
220
100
SPARK
145
120
140
100
110
140
SPARK
110
200
220
190
125
180
SPARK
150
210
110
130
130
80
ACA
90
145
200
190
240
250
ACA
80
145
190
200
240
240
ACA
45
60
110
130
170
200
ACA
75
135
200
200
240
250
DCMA
400
720
1100
1000
1400
1450
DCMA
300
740
1000
1100
1350
1300
DCMA
180
260
500
580
850
1150
DCMA
320
700
1100
1020
1000
1400
FIELD DC KV
H 32
G 34
F 22
E 25
D 24
C 22
Chambers 11
FIELD DC KV
H 32
G 33
F 28
E 26
D 23
C 22
Chambers 13
FIELD DC KV
H 32
G 34
F 29
E 25
D 24
C 23
Chambers 15
FIELD DC KV
H 31.5
G 32.5
F 27
E 25
D 24
C 27.5
ACV
200
230
210
210
200
180
& 12
ACV
200
230
220
210
200
190
& 14
ACV
210
230
210
200
200
190
& 16
ACV
210
230
200
200
195
170
SPARK
120
220
90
20
100
100
SPARK
140
130
120
50
110
20
SPARK
180
170
130
70
140
100
SPARK
90
120
240
100
80
50
ACA
50
100
195
195
250
250
ACA
50
100
170
195
250
250
ACA
50
85
135
195
250
250
ACA
50
115
175
190
250
250
DCMA
200
450
1000
1120
1450
1550
DCMA
180
500
1000
1040
1450
1400
DCMA
200
380
800
1040
1400
1450
DCMA
200
500
840
1000
1450
1900
175
-------
Navajo Generating Station
Unit #3
Voltage Current Readings
Date: 8/3-4/77
Chambers 1 & 2
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
DC
35.
33.
28
25
24.
23.
3
DC
26.
35
29
26
23.
22
5
DC
33
33
29
26.
24
27.
7
DC
33.
30
25.
26
23.
22.
KV
5
5
5
5
& 4
KV
5
5
& 6
KV
5
5
& 8
KV
5
2
5
5
ACV
225
215
220
190
210
195
ACV
175
230
215
200
200
190
ACV
200
225
210
200
200
190
ACV
210
220
220
205
190
185
SPARK
110
130
125
155
120
50
SPARK
230
125
75
80
140
120
SPARK
100
140
125
120
200
110
SPARK
120
125
50
40
90
70
ACA
85
145
190
195
235
250
ACA
90
125
200
200
250
240
ACA
60
75
145
165
235
240
ACA
105
150
200
205
250
250
DCMA
360
620
1060
980
1400
1450
DCMA
400
570
1100
1100
1350
1350
DCMA
200
340
740
800
1300
1300
DCMA
420
760
1100
1120
1150
1400
Time:
23
Chambers
FIELD
H
G
F
E
D
C
DC
33
35
27
26
25
22
Chambers
FIELD
H
G
F
E
D
C
DC
33
35
30
27
24
22
Chambers
FIELD
H
G
F
E
D
C
DC
33
35
31
27
24
23
Chambers
FIELD
H
G
F
E
D
C
DC
32
34
28
26
24
21
:00
9 & 10
KV
.5
.5
.5
.5
11
KV
.5
.2
13
KV
.5
15
KV
.5
.5
.5
.5
ACV
205
240
220
220
205
190
& 12
ACV
215
240
230
220
210
195
& 14
ACV
215
240
230
210
200
190
& 16
ACV
210
240
210
200
200
260
SPARK
110
170
150
140
120
180
SPARK
140
130
180
130
230
130
SPARK
160
110
200
110
210
100
SPARK
150
160
120
210
60
60
ACA
40
120
190
195
250
250
ACA
40
120
175
185
240
250
ACA
45
85
180
170
245
250
ACA
40
90
185
185
240
190
DCMA
200
480
960
1100
1550
1500
DCMA
180
600
960
1010
1400
1400
DCMA
200
480
1000
940
1400
1450
DCMA
180
460
1020
1000
1400
1800
176
-------
Date:
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
8/3-4/77
1
DC
34.
32.
27
24.
23.
23.
3
DC
34.
34
28
25
22.
21
5
DC
33
32
28
25.
23.
22
7
DC
33
29
24.
25
23
22
& 2
KV
5
5
5
5
5
& 4
KV
5 .
5
& 6
KV
5
5
& 8
KV
5
ACV
215
210
215
195
200
190
ACV
220
225
205
200
190
180
ACV
200
210
200
190
200
190
ACV
205
210
215
200
185
180
SPARK
110
100
100
90
110
125
SPARK
125
110
210
180
130
100
SPARK
140
140
190
150
130
190
SPARK
110
190
70
120
150
60
ACA
80
150
195
195
245
250
ACA
90
140
160
200
240
240
ACA
50
55
125
145
205
235
ACA
75
155
200
200
250
250
Time :
DCMA
280
740
1080
1000
1400
1450
DCMA
380
640
1060
1100
1300
1350
DCMA
220
280
600
1020
1200
1300
DCMA
300
700
1100
1100
1150
1400
Navajo Generating Station
Unit #3
Voltage Current Readings
03:00
Chambers 9 & 10
FIELD
H
G
F
E
D
C
DC
33
34.
22
25
24
22
Chambers
FIELD
H
G
F
E
D
C
DC
32
34
30
27
23.
22
Chambers
FIELD
H
G
F
E
D
C
DC
32.
36
30
26
24
23
Chambers
FIELD
H
G
F
E
D
C
DC
32
34
27.
26.
24
20.
KV
5
11
KV
5
13
KV
5
15
KV
5
5
5
ACV
205
235
215
205
200
185
& 12
ACV
210
250
220
210
205
190
& 14
ACV
210
250
225
210
195
185
& 16
ACV
210
240
205
200
200
250
SPARK
90
125
130
110
180
180
SPARK
130
130
280
90
220
90
SPARK
150
130
160
90
160
70
SPARK
140
180
260
300
90
30
ACA
35
110
190
195
250
250
ACA
45
120
185
193
250
250
ACA
40
100
190
195
250
250
ACA
35
110
185
190
250
190
DCMA
240
580
1000
1000
1400
1350
DCMA
200
480
1000
1020
1425
1450
DCMA
180
460
1020
1040
1400
1800
177
-------
Date:
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
8/4-5/77
1
DC
34
32.
25.
24
23
22.
3
DC
35
33.
27.
24.
22
20.
5
DC
33
33
28.
25.
23
21
7
DC
33
26.
25
25
22
22
& 2
KV
5
5
5
& 4
KV
5
5
5
5
& 6
KV
5
5
& 8
KV
5
ACV
210
200
200
180
190
185
ACV
210
210
200
190
190
185
ACV
195
205
190
180
190
175
ACV
195
150
200
175
175
180
SPARK
120
200
180
170
155
125
SPARK
150
280
210
280
220
180
SPARK
125
150
190
150
110
130
SPARK
130
0
120
110
175
120
ACA
60
120
160
190
225
215
ACA
95
120
150
180
220
220
ACA
42
47
95
150
190
190
ACA
60
10
155
140
220
255
Time:
DCMA
280
530
640
920
1250
1200
DCMA
330
500
750
880
1200
1200
DCMA
150
210
430
560
900
1000
DCMA
260
80*
740
800
900
1400
Navajo Generating Station
Unit #3
Voltage Current Readings
23:00
Chambers 9 & 10
FIELD
H
G
F
E
D
C
DC
31.
34
26.
25
23
20.
Chambers
FIELD
H
G
F
E
D
C
DC
32
33
28
26.
22
20.
Chambers
FIELD
H
G
F
E
D
C
DC
32
33.
29.
25
23
21.
Chambers
FIELD
H
G
F
E
D
C
DC
32
32.
26.
25
23
20
KV
5
5
5
11
KV
5
5
13
KV
5
5
5
15
KV
5
5
ACV
190
210
205
200
185
170
& 12
ACV
200
220
200
200
190
180
& 14
ACV
210
210
200
200
190
180
& 16
ACV
210
220
190
185
190
250
SPARK
120
230
200
210
170
170
SPARK
155
130
140
190
190
150
SPARK
170
170
160
130
130
190
SPARK
120
100
160
150
185
240
ACA
45
42
165
150
205
205
ACA
40
50
130
155
220
225
ACA
40
50
110
120
230
250
ACA
32
65
145
135
235
170
DCMA
180
260
880
800
1200
1200
DCMA
160
220
660
1060
1150
1150
DCMA
160
240
560
860
1250
1450
DCMA
180
300
730
700
1300
1525
* suspected field out
FIELD DC KV ACV
back in G 28.5 200
SPARK ACA DCMA
140 135 580
178
-------
Navajo Generating Station
Unit #3
Voltage Current Readings
Date: 8/4-5/77
Chambers 1 S, 2
Time:
FIELD
H
G
F
E
D
C
Chambers
FIELD
H
G
F
E
D
C
DC
33
32
26
23
22.
22
3
DC
34
33
27
24
21.
20
Chambers 5
FIELD
H
G
F
E
D
C
DC
32
32
28
25
22.
20.
Chambers 7
FIELD
H
G
F
E
D
C
DC
31.
26
23
24
22.
21.
KV
5
& 4
KV
5
& 6
KV
5
5
& 8
KV
5
5
5
ACV
190
185
200
180
185
178
ACV
200
200
190
175
185
170
ACV
190
200
170
180
170
165
ACV
180
145
160
130
160
175
SPARK
130
130
150
130
160
220
SPARK
170
185
190
320
200
170
SPARK
160
170
170
190
140
220
SPARK
170
0
0
0
200
200
ACA
50
135
165
190
205
200
ACA
1 75
75
140
165
210
200
ACA
42
45
50
120
145
180
ACA
40
10
50
0
135
200
DCMA
220
560
720
1020
1050
1100
DCMA
260
360
700
800
1100
1050
DCMA
120
180
240
530
750
950
DCMA
160
70*
200
20*
400
1050
03:00
Chambers 9 & 10
FIELD
H
G
F
E
D
C
DC
32
33
27
25
23
20.
Chambers
FIELD
H
G
F
E
D
C
DC
32
33.
28.
26.
22
20.
Chambers
FIELD
H
G
F
E
D
C
DC
31.
35
29
25
23
21.
Chambers
FIELD
H
G
F
E
D
C
DC
31
32.
26
25
22.
20.
KV
5
11
KV
5
5
5
5
13
KV
5
5
15
KV
5
5
5
ACV
200
210
200
200
185
165
& 12
ACV
205
220
200
205
190
180
& 14
ACV
210
225
205
200
190
180
& 16
ACV
205
220
190
185
185
250
SPARK
110
170
250
140
160
300
SPARK
130
100
110
125
140
110
SPARK
130
125
160
170
230
170
SPARK
120
100
170
220
200
330
ACA
45
50
145
160
200
210
ACA
43
55
170
170
215
ACA
40
55
125
175
230
250
ACA
40
55
150
150
220
170
DCMA
200
320
820
840
1150
1200
DCMA
200
270
660
840
1150
DCMA
180
220
640
900
1300
1500
DCMA
180
240
760
740
1200
1400
* Fields with electrical problems - E Field operating at near normal
at ^03:30, G Field remained low throughout test.
179
-------
APPENDIX 4
SIZE-DEPENDENT ELEMENTAL CONCENTRATION DATA
180
-------
ELEMENTAL CONCENTRATIONS IN MILLIGRAMS/DSCM/CYCLONE
CYCLONE RUN 13 CHAMBER #8, INLET 7/14-15/77
D50
00
7.2
3.5
2.3
1.2
0.5
7.2
3.5
2.3
1.2
0.5
6.8
3.2
2.1
0.96
0.46
6.8
3.2
2.1
0.96
0.46
6.8
3.2
2.1
0.96
0.45
6.8
3.2
2.1
0.96
0.45
Cyclone #
1
2
3
4
5
Ca
Ti
Ba
Cr
Mn
Fe
Cu
2.10E+01
9.91E+00
3.40E+00
2.15E+00
3.39E-01
Zn
2.97E-01
2.14E-01
1.15E-01
l.OOE-01
1.36E-02
1
6
2
1
2
5
2
3
1
1
.52E+02
.07E+01
.17E+01
.26E+01
.07E+00
As
.56E-02
.51E-02
. 33E-02
. 02E-02
.61E-03
2.48E+01
9.06E+00
3.15E+00
1.90E+00
3.79E-01
Pb
8.32E-02
7.41E-02
4.77E-02
3.14E-02
6.66E-03
CYCLONE RUN #5
K
7.01E-02
3.88E-02
4.34E-02
5.11E-02
7.96E-03
Zn
2.28E-03
1.28E-03
1.49E-03
2.52E-03
4.90E-04
5
3
3
3
6
1
6
1
2
6
Ca
.87E-01
.16E-01
.03E-01
.45E-01
.22E-02
AS
. 06E-04*
.31E-05*
. 94E-04
.30E-04
. 80E-05
Ti
7.96E-02
4.27E-02
4.31E-02
5.40E-02
9.72E-03
PD
1.35E-03
7.40E-04
6.38E-04
8.42E-04
1.49E-04
CYCLONE RUN #7
K
1.17E+01
2.51E+01
1. 01E+01
5.02E+00
1.78E+00
Zn
1.02E-01
2.56E-01
1.61E-01
1.09E-01
4.25E-02
4
8
3
1
5
2
8
2
1
8
Ca
.83E+01
.95E+01
.44E+01
.64E+01
.46E+00
AS
.2 IE- 02
. 09E-02
. 39E-02
. 22E-02
.49E-03
Ti
1.05E+01
1.90E+01
7.68E+00
3.48E+00
1.33E+00
Pb
4.84E-02
7.11E-02
6.55E-02
4.37E-02
1.63E-02
9.
5.
2.
2.
6.
2.
1.
8.
7.
2.
44E-01*
88E-01*
79E-01*
37E-01*
43E-02*
Br
23E-02*
69E-02*
57E-03*
42E-03*
01E-03*
CHAMBER #8,
5.
3.
4.
6.
1.
1.
1.
1.
2.
4.
Ba
93E-03*
40E-03*
46E-03*
40E-03*
43E-03*
Br
65E-04*
01E-04*
41E-04*
01E-04*
74E-05*
MAIN INLET
3.
9.
4.
3.
1.
9.
2.
1.
9.
3.
Ba
96E-01*
92E-01*
53E-01*
10E-01*
18E-01*
Br
61E-03*
75E-02*
28E-02*
39E-03*
54E-03*
2.73E+00
1.38E+00
6.26E-01
4.15E-01
1.11E-01
Rb
2.14E-01
8.05E-02
3.03E-02
1.45E-02
2.43E-03
1.78E-01*
1.06E-01*
4.89E-02*
1.90E-01
1.08E-02*
Sr
6.37E+00
2.15E+00
7.30E-01
3.97E-01
7.81E-02
3.
9.
4.
3.
1.
7.
1.
5.
3.
5.
46E-01
19E-02*
29E-02*
68E-02*
51E-02
Zr
OOE-01
84E-01
52E-02
92E-02
12E-03*
1.28E+02
4.78E+01
1.72E+01
1.07E+01
1.69E+00
Mo
1.11E-01*
5.27E-02
3.94E-02*
9.19E-02
9.22E-03*
2.19E-01
l.OOE-01
3.63E-02
2.62E-02
7.34E-03
OUTLET 7/18-19/77
V
1.70E-02
9.26E-03
1.02E-02
1.41E-02
3.38E-03
Rb
5.16E-04
2.70E-04
3.32E-04
4.04E-04
4.23E-05
8/3-4/77
V
1.22E+00
2.36E+00
8.85E-01
6.08E-01
2.26E-01
Rb
1.25E-01
2.66E-01
9.64E-02
4.30E-02
1.85E-02
Cr
1.04E-03*
5.87E-04*
7.36E-04*
1.46E-03
2. 32E-04*
Sr
2.04E-02
1.08E-02
9.98E-03
1.16E-02
2.16E-03
Cr
7.49E-02*
1.80E-01*
8.23E-02*
5.49E-02*
2.12E-02*
Sr
2.51E+00
4.37E+00
1.62E+00
7.02E-01
2.71E-01
8.
5.
6.
9.
2.
1.
6.
6.
8.
1.
2.
4.
1.
9.
3.
3.
5.
1.
6.
2.
Mn
95E-04*
11E-04*
47E-04*
26E-04*
08E-04*
Zr
30E-03
23E-04
25E-04
04E-04
20E-04*
Mn
04E-01
11E-01
38E-01
08E-02
37E-02
Zr
93E-01
56E-01
58E-01
40E-02
12E-02
Fe
3.91E-01
2.06E-01
2.09E-01
2.55E-01
4.16E-02
Mo
7.77E-04*
4.73E-04*
6.40E-04*
9.40E-04*
2.16E-04*
Fe
5.81E+01
1.03E+02
3.95E+01
1.84E+01
7.11E+00
Mo
4.61E-02*
1.22E-01*
5.67E-02*
4.20E-02*
1.59E-02*
Cu
9.36E-04
3.78E-04
7.27E-04
7.36E-04
1.53E-04
Cu
8.03E-02
1.62E-01
7.45E-02
3.90E-02
1.35E-02
*Denotes upper limit of element not found.
-------
00
to
Cyclone ft
1
2
3
4
5
Zn
Zn
0.600
0.600
0.700
1.000
0.200
K
0.736
0.890
0.938
1.000
0.916
Zn
0.333
0.333
0.667
1.000
1.000
ENRICHMENT RATIO/ELEMENT/CYCLONE, NORMALIZED TO Fe
CYCLONE RUN S3 CHAMBER #8, INLET 7/14-15/77
Ca Ti Ba V Cr
0.792
1.000
0.957
0.971
0.971
0.934
1.000
0.995
0.929
0.968
0.858
0.344
0.813
0.791
1.000
As
Ca
As
0.000*
0.000*
0.500
0.500
1.000
Ca
0.934
0.976
0.980
1.000
0.865
As
0.000
000
000
000
Pb
0.222
0.444
0.778
1.000
0.889
0.000
0.500
1.000
0.500
0.500
0.250
0.500
0.750
0.750
1.000
0.865
0.671
1.000
0.966
0.923
0.977
1.000
0.942
0.881
0.973
0.872
0.889
0.880
0.906
1.000
Br
0.000*
0.000*
0.000*
1.000*
1.000*
CYCLONE RUN #5 CHAMBER
Ti Ba
0.441*
0.500*
0.618*
0.735*
1.000*
Pb
.750
.000
.750
.750
Br
1.000
0.933
0.948
1.000
0.974
0.969
Pb
0.500
0.500
1.000
1.000
1.000
1.000
0.000*
0.000*
1.000*
1.000*
1.000*
0.412*
0.588*
0.647*
1.000*
1.000*
Br
0.000*
0.000*
0.000*
0.000*
1.000*
0.318
0.439
0.545
0.591
1.000
Rb
1.000
1.000
1.000
0.500
0.500
, OUTLET
V
0.531
0.556
0.605
0.691
1.000
Rb
0.500
0.500
1.000
1.000
0.500
8/3-4/77
V
0.636
0.697
0.667
1.000
0.970
Rb
0.667
1.000
0.667
1. 000
0.667
0.056*
0.111*
0.167*
1.000
0.333*
Sr
1.000
0.900
0.860
0.740
0.920
7/18-19/77
Cr
0.500*
0.500*
0.667*
1.000
1.000*
Sr
0.981
1.000
0.906
0.868
0.981
Cr
0.333*
0.667*
0.667*
1.000*
1.000*
Sr
1.000
0.977
0.953
0.884
0.884
Mn
Zr
1.000
0.800
0.600
0.800
0.600*
Mn
0.400*
0.400*
0.600*
0. 800*
1.000*
Zr
.000
.000
.000
.000
1.000*
Mn
0.800
0.800
0.600
1.000
1.000
Zr
Fe
Mo
0.111*
0.111
0.222*
1.000
0.556*
Fe
.000
.000
.000
.000
1.000
Mo
0.400*
0.400*
0.800*
1.000*
1.000*
Fe
.000
.000
.000
.000
1.000
Mn
1.000
0.977
0.953
0.884
0.884
1.000
0.714
0.571
0.429
0.429
0.500*
0.500*
0.500*
1.000*
1.000*
Cu
Cu
0.500
0.500
0.750
0.750
1.000
Cu
0.500
000
000
000
1.000
*Denotes upper limit of element not found.
-------
TECHNICAL REPORT DATA
(Please read fmtniciions on i/ie reverse before completing)
1. REPORT NO.
EPA-600/7-78-214
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Performance and Economic Evaluation of a
Hot-side Electrostatic Precipitator
5. REPORT DATE
November 1978
G. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
G. H. Marchant Jr. and J. P. Gooch
SORI-EAS-78-415
3764-XXIIIDF
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Southern Research Institute
2000 Ninth Avenue, South
Birmingham, Alabama 35205
10. PROGRAM ELEMENT NO.
EHE624
11. CONTRACT/GRANT NO.
68-02-2185
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 PERIOD COVERED
Final; 12/76 - 9/78
14. SPONSORING AGENCY CODE
EPA/600/13
15. SUPPLEMENTARY NOTES IERL_RTP project officer is Leslie E Sparks, Mail Drop 61, 919/
541-2925.
B. ABSTRACT
gjves results of meas urements - - to determine the overall mass
and fractional collection efficiency of a hot-side electrostatic precipitator (ESP)--
across 1 chamber of a 16-chambered ESP. Measurements of fractional efficiency were
conducted across the entire ESP. In situ and laboratory resistivity measurements
were performed, and voltage -cur rent characteristics of the power supplies were ob-
tained. An engineering analysis was conducted, including an estimate of the specific
collecting area required for a cold-side ESP on the same boiler. Results include:
(1) voltage waveforms and secondary voltage -cur rent relationships showed character-
istics similar to back-corona although fly ash resistivity was 5 x 10 to the 9th power
ohm-cm at 350 C (in situ determination); (2) ESP operation was sensitive to resistivity
variation in a resistivity region (2 x 10 to the 10th power to 8 x 10 to the 8th power
ohm-cm from laboratory determinations) where no sensitivity was expected; (3) over-
all mass collection efficiency of an isolated chamber was 99.22% for a specific col-
lection area of 52. 6 sq m/(cu m/sec), average secondary voltage was 22 kV, and
average secondary current density was 40 nA/sq cm; and (4) the turnkey cost of the
ESP system was estimated at #34,940,000 (S44/kW) in 1977 dollars.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
C. COSATI Picld/Group
Air Pollution
Electrostatic Precipitation
Performance Evaluation
Cost Analysis
Fly Ash
Air Pollution Control
Stationary Sources
Hot-side ESP
13B
13H
05A
14A
21B
IS. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (Tin's Report)
Unclassified
21. NO. OF PAGES
192
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
133
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