EPA-650/2-74-053
JUNE 1974
Environmental Protection Technology Series
-------
EPA-650/2-74-053
PARTICULATE COLLECTION STUDY,
EPA/TVA FULL-SCALE DRY
LIMESTONE INJECTION TESTS
by
R.F. Brown
Cottrell £' vironmental Systems, Inc.
Division of Research-Cottrell, Inc.
P. O. Box 750
Bound Brook. N. J. 08805
Contract No. CPA 22-69-139
ROAPNo. 21ACY-16
Program Element No. 1AB013
EPA Project Officer: R.D. Stern
Control Systems Laboratory
National Environmental Research Center
Research Triangle Park, North Carolina 27711
Prepared for
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
June 1974
-------
This report has been reviewed by the Environmental Protection Agency
and approved for publication. Approval does not signify that the
contents necessarily reflect the views and policies of the Agency,
nor does mention of trade names or commercial products constitute
endorsement or recommendation for use.
11
-------
-111-
ABSTRACT
A particulate control system consisting of a mechanical
cyclone-electrostatic precipitator combination has been
evaluated on a full-scale boiler without and with limestone
injection (dry) into the boiler for sulfur oxide removal.
The main objective of the study was to determine the effects
of dry additive injection on the particulate control equip-
ment and evaluate system modification alternatives including
a cost benefit analysis that will maintain stack particulate
emissions with injection equivalent to about 2.8% sulfur
and 15.5% ash coal-firing without injection.
Two separate test programs by Cottrell Environmental Systems
were conducted, one in December, 1969 which quantified the
collection system on coal-firing only to serve as a perfor-
mance baseline and the other in July, 1971 in which coal sul-
fur and flue gas temperature, along with limestone particle
size and amount injected were studied at two levels. A third
more comprehensive test program without limestone injection
by the Tennessee Valley Authority in the summer of 1970 has
been used to establish the baseline conditions for the elec-
trostatic precipitator and boiler flue gas. Mechanical col-
lector performance did not vary substantially whether fly ash
alone was collected or in combination with coarse or fine
limestone. Efficiencies measured were in the 50 to 60% range
depending upon pressure loss across the collector. Therefore,
the overall efficiency of the dust collection equipment was
a significant function of the precipitator performance and
inlet loading only. In general, as expected, the electro-
static precipitator performance was adversely affected by
limestone injection. It was found that the precipitation
rate parameter without and with limestone injection was main-
ly a function of corona power density input, and that the
power level and therefore the performance reached without
excessive sparking was lower in the limestone injection cases.
The average particulate emission rate and flue gas conditions
found on #10 boiler at Shawnee Station of TVA with the pres-
ently installed dust collection equipment were 412 Ibs/hr
and 570,000 cfm at 309°F. Cost estimates for size modifi-
cation to the presently installed precipitator to maintain
baseline emission with limestone injection have been con-
sidered for flue gas temperatures into the precipitator of
250 and 309. Other options such "hot" precipitator, gas
-------
-IV-
conditioninq and precipitator energization modifications have
been discussed but since actual performance data for these
alternatives was beyond the scope of this experimental pro-
gram, only speculative comments have been made as to expected
results. For coarse limestone injection, the present precipi-
tator on boiler #10 at 309F would have to be increased in
size about 45% in order to maintain the desired emission
level stipulated above. If it is feasible to reduce the gas
temperature to about 250F, the size increase required would
only be 17%. On the other hand with fine limestone injection,
the size increases at 309 and 250F would be 225% and 56% re-
spectively.
For the grassroots plant, the evaluation shows a cold pre-
cipitator (250F) as the best option on a cost basis.
-------
-v-
SUMMARY
The KnvJronmenl.il Protection Aqoncy is sponsoring a variety
of proqrnms to develop Lechnically feasible and economic
means for removing sulfur oxides from stack gases of fossil
fuel-fired boilers. One such means is the injection of dry
limestone into the hot gas zone of the boiler where the gas-
eous sulfur oxides react with the finely dispersed additive
to form solid sulfur-additive compounds which can be removed
from the flue gas in mechanical and/or electrostatic precipi-
tator collectors.
This report presents solid collection system performance
results obtained from 37 test runs on a full-scale plant
firing pulverized coal and having a dry additive injection
system. The major variables studied include flue gas tem-
perature into the dust collecting equipment, coal sulfur,
and additive stoichiometry and particle size. Two levels
of each variable were investigated. These tests and data
from other pertinent sources have been analyzed and corre-
lated. The results are summarized as follows:
(1) The performance of the mechanical collector
was relatively insensitive to all test con-
ditions of injection or non-injection ranging
between 50 and 60% efficiency. On the other
hand, the overall efficiency of the dust
collection system varied broadly between 72
and 99% depending significantly on the
electrostatic precipitator performance. With-
out limestone injection, flue gas temperature
and volume, and coal sulfur were the critical
variables while with injection, the particle
size of the additive was another important
parameter.
(2) The precipitation rate parameter was a signi-
ficant semi-logrithmic function of the corona
power input density.
W = 0.47+0.161n P (No Injection)
f\
W = 0.52+0.121n P (Coarse Additive Injection)
£\
W = 0.46+0.141n P (Fine Additive Injection)
£\
where,
W = precipitation rate parameter (FPS)
P = corona power input density
(kilowatts/1000 ft2 of collecting
surface)
-------
-VI-
In genera], the precipitator performance
was poorer with limestone injection because
the maximum corona input power density
attainable was lower, particularly when fine
limestone was injected.
(3) A correlation of use in sizing electrostatic
precipitators was found by examining the
affects of the parameters of limestone par-
ticle size, flue gas temperature, coal sulfur
and limestone injection rate on corona power
input density. The correlation resulted in
the following equations:
(coarse)
10.0 3.87
~L ~T
(fine)
PA = -0.990 + 0.199S -
where,
S - coal sulfur fired (tons/hr)
L = limestone injected (tons/hr)
_2
T = flue gas temperature (°F x 10 )
By use of these equations and the correlation
between precipitation rate parameter and
power density shown above, and standard design
equations, it is possible to size a precipita-
tor within the following limiting conditions:
Coal Sulfur Fired (S)
1.0 to 3.2 tons/hr
Limestone Feedrate (L)
5.3 to 16.8 tons/hr.
Flue Gas Temperature (T)
(240 to 315) (10-2)°F.
Stoichiometry 0.28(L/S) = 1.0 to 4.0
(4) Mechanical collector fractional efficiency curves
based on Bahco analysis of collected samples
for fly ash ash alone and fly ash plus additive
reaction products were essentially the same
ranging from 25% on the 5 micron size to 90 to
95% on the greater than 25 micron size. However,
-------
-vii-
the electrostntac prccipitator fractional
efficiency curve on fly ash alone was nearly
constant over A particle size range from 2 to
30^, i.e. 80 t-.o 90%. With limestone injection,
t.h*j bloc'rocilat j c precipitator showed decreas-
inq collection efficiency as particle size
increased. The fly ash alone had an average
mean size by weight of 19 microns at the
mechanical collector inlet while with both
coarse and fine limestone injection, the mean
size was about 9 microns.
The average particulate loading at the
mechanical outlet-precipitator inlet varied
linearly with limestone injection rate
ranging from 1.5 grains per scf at 0 feedrate
to about 4.0 grains at 16 tons/hr.
(5) Laboratory particle resistivity measurements,
in general, were higher than in-situ resis-
tivities on samples from the same test both
with and without limestone injection.
The criticality of coal sulfur and moisture
on particle resistivity was verified by
in-situ measurements without limestone in-
jection, particularly at the lower gas tempera-
tures.
With limestone injection, the effect of
sulfur appeared to be random, but moisture
conditioning at lower temperatures was still
evident.
(6) The precipitation rate parameter degradation
as a function of particle resistivity was
demonstrated. However, the critical range of
resistivity seemed to be occurring in the
10H to 1Q13 ohm-cm range which is somewhat
higher than published figures. A possible
explanation is the "in-situ" resistivity
measuring technique.
(7) There was no obvious correlation between the
chemical composition of the particulate and
the performance of the precipitator.
(8) An optical sensor installed on the precipita-
tor outlet duct provided a good qualitative
indication of boiler and dust collecting
equipment operation. There appeared to be a
linear relationship between outlet particulate
loading and sensor output voltage. However,
the necessity for maintaining clean lenses was
evident.
-------
-Vlll-
(9) Using a baseline of 412 pounds emitted/hr and
570,000 cfm of flue gas at 309F, estimated
costs of the fly ash only electrostatic pre-
cipitator (installed) at 309F was compared
with one at 600F. In addition, size modifi-
cations and costs for electrostatic precipi-
tators with coarse and fine limestone injec-
tion (2 x stoichiometry) were compared at 250,
309, and 600F.
The following summarizes the results:
Electrostatic Precipitator ******
Cost and Size Factors 250F 309F 309F 600F (See pqs,
171 and
172)
Cost
Installed ($/Kilowatt)
No Injection - 2.21 2.99 5.85
Coarse Injection 2-58 3.21 3.95 7.10
Fine Injection 3.44 7.20 8.89 7.10
Size
Factor (x no injection
at 309F = 1.0)
No Injection - 1.0 1.35 2.44
Coarse Injection 1-17 1-45 1.79 2.96
Fine Injection 1-56 3.25 4.02 2.96
* Follows Mechanical Collector
** Straight Precipitator
Coarse limestone at a flue gas temperature
around 25OF emerged as the best alternative
for the limestone injection cases when only
considering precipitator size modification.
However, the present Shawnee boiler flue
gas is about 3OOF and would require cooling
in order to take advantage of the 25OF re-
sult. This added cost could offset the
difference between coarse limestone at 309F
at S3.21/KW and $2.59/KW at 250F. With fine
limestone injection, the precipitator size
requirements at 250F are still at a minimum
but as above, extra cost for gas cooling
would be required. With fine limestone in-
jection, the requirements at 309F and 600F
are for all practical purposes equivalent.
-------
-IX-
It is of interest to compare a straight hot
precipitator at 600F with a straight 309F pre-
cipitator on fine limestone injection.
The size factors are 2.96 and 4.02 respectively
with the installed $/KW being $7.10 and $8.89
respectively. Clearly, the hot precipitator
is advantageous for this case.
-------
TABLE OK CON'TJIKTS
TITLE P?.GE
ABSTRACT
SUMMARY
I.
II.
III.
IV.
V.
VI.
INTRODUCTION1
TECHNICAL APPROACH
TEST METHODS
3. Particulate Sampling
4 . Test Sections
5. In-Situ Resistivity
6. Laboratory Resistivity
7. Skeletal or True Densitv
8. Particle Size
9. Stack Opacity
10- Coal Analysis '
TEST CONDITIONS AND PROCEDURES
TEST RESULTS AND SAMPLE ANALYSES
1. Test Data
2. Coal Analyses
5. Chemical Analyses
ANALYSIS AND DISCUSSION OF TEST RESULTS . .
1. Electrostatic Precipitator Performance
.... 1
.... 3
.... 6
.... 6
.... 7
.... 8
.... 11
.... 13
.... 13
.... 22
.... 24
.... 26
. . . .' 26
.... 28
. . . -. 38
..... 38
.... 38
.... 39
.... 39
.... 39
.... 70
.... 70
A. Theoretical Considerations of Electrostatic
Performance As A Function of Corona Power . . 72
B. Correlation of Precipitator Performance
With Corona Pc\;or Input 77
C. Correlation of Precipitator Corona Power
Input VJith Process Variables 91
Performance of The Combination Mechanical-
Electrostatic Dust Collector 97
A. Correlation of Particle Size 7*nd Dust.
Collector Performance 99
Discussion of Particle Resistivity Data 129
A. Correlation of In-Situ And Laboratory
Measurements 129
B. Relationship of Particle Resistivity, Flue
Gas Temperature, and Coal Sulfur (No
Limcr.tone Injection) 140
C. Relationship of Particle Resistivity, F]ue
Gas Temperature, and Coal Sulfur (VJith
Limestone Injection) 140
D. Relationship fiett.-oen Precipitation Rate
Parameter and Particle Resistivity 143
-------
TAKJ.H OF CO.MTKHTS (Continued)
>aqe
4. Discu.'-.jjion of Chemical Analyses Results 147
7v, Kelationship of Calcium -Compounds at
Electrostatic Precipitator Inlet V'ith
Limestone Feedrate 147
B. Examination of Particle Resistivity At The
PrecipiLator Inlet Ah 7\ Function of
Calcium Oxiue/Sulfur Ratio for High and Low
Temperature Flue Gas 151
5. Review of Optical Sensor Data 153
VIJ. TECHNO-ECONOMIC EVALUATION OF VARIOUS ALTERNATIVES
FOR MAINTAINING THE STACK EMISSION RATK WITH
LIMESTONE INJECTION EQUIVALENT TO A BASELINE
CONDITION OF NO LIMESTONE INJECTION 166
1. Size Hodificatjon of The Presently Insiailed
Dust Collecting System 168
2. Installation of A "Hot" Precipitator 171
3. Gas Cooling Ahead of The Dust Collection System . . 173
4. Gas Conditioning Ahead of The Dust Collecting
System 173
5. Electrical Energization of The Precipitator .... 175
VIII. RECOMMENDATIONS 384
BIBLIOGRAPHY 186
TECHNICAL DATA/ABSTRACT SHEET 188
-------
TABLE or COUTTNTS (Continued)
LIST OP XIGURFS
FIGURE 1 - EQUIPMENT FOR MAKING GAS VELOCITY MEASUREMENTS
AND TAKING PARTICULATE SAMPLES 9
FIGURE 2 -- SCHEMATIC DIAGRAM OF BOILER #10 SHAWNEE
STATION, TVA 12
FIGURE 3 - DETAILS OF MECHANICAL COLLECTOR INLET
SAMPLING STATION 14
FIGURE 4 - DETAILS OF MECHANICAL COLLECTOR OUTLET -
ELECTROSTATIC PRECIPITATOR INLET SAMPLING
FIGURE 5
FIGURE 6
FIGURE 7
FIGURE 8
FIGURE 9
FIGURE 10
FIGURE 11
FIGURE 12
FIGURE 13
FIGURE 14
FIGURE 15
- DETAILS OF ELECTROSTATIC PRECIPITATOR OUTLET
SAMPLING STATION
- IN-SITU RESISTIVITY APPARATUS
- POINT-PLANE RESISTIVITY CELL
- LABORATORY RESISTIVITY MEASURING APPARATUS . . .
- SCHEMATIC DIAGRAM OF LABORATORY RESISTIVITY
MEASURING APPARATUS
- CROSS-SECTION DIAGRAM OF MEASURING CELL USED IN
LABORATORY RESISTIVITY APPARATUS
- SCHEMATIC OF ELECTRIC CIRCUIT FOR LABORATORY
RESISTIVITY APPARATUS
- APPARATUS FOR MEASURING SKELETAL OR TRUE
DENSITY OF PARTICULATE
- liAHCO CENTRIFUGAL PARTICLE CL7kSS3FIEU
- FUNCTIONAL DIAGRAM OF THE OPTICAL SENSOR ....
- SCHEMATIC DIAGRAM OF ELECTROSTATIC PRECIPITATOR
ARRANGEMENT AND ELECTRICAL HOOK-UP
] 6
1 7
18
19
20
21
21
23
2r>
27
29
FIGURE 16 - REPRESENTATIVE TEMPERATURE AND VELOCITY
TRAVERSE AT THE MECHANICAL COLLECTOR INLET
("B" SIDE) 33
FIGURE 17 - REPRESENTATIVE TEMPERATURE AND VELOCITY
TRAVERSE AT Ti'.K MECHANICAL COLLECTOR OUTLET -
PRECIPITATOR INLET SAMPLE STATION ("B" SIDE) . . 34
FIGURE 18 - REPRESENTATIVE TEMPERATURE AND VELOCITY
TRAVERSE AT THE PKECIP1TATOK OUTLET SAMPLING
STATION ("B" SIDi-J) 35
": 19 - PRECIPITATION RATE PARAMETER AS A FUNCTION OF
CORONA POWER DENSITY FOR TESTS WITHOUT LIMESTONE
INJECTION 78
-------
TABU: OF CONTENTS (continued)
LIST OK FIGURI.S
paac
FIGURE 20 - COMPARISON OF DATA FROM FIGURE 19 WITH
PUBLISHED DATA OF SOUTHERN RESEARCH
INSTITUTE FOR VARIOUS FLY ASH PRECIPITATOR
INSTALLATIONS - REF. (11) 82
FilGURE 21 - LOSS IN COLLECTION EFFICIENCY AS A FUNCTION
OF POWER RATE FOR TESTS WITHOUT LIMESTONE
INJECTION 84
FIGURE 22 - COMPARISON OF DATA FROM FIGURE 21 WITH
PUBLISH!:!) DATA OF SOUTHERN RESEARCH
INSTITUTE FOR VARIOUS FLY ASH PRECIPITATOP.
INSTALLATIONS - REF, (11) 85
FIGURE 23 - PRECIPITATION RATE PARAMETER AS A FUNCTION
OF CORONA POWER DENSITY FOR TESTS WITH
LIMESTONE INJECTION 87
FIGURE 24 - LOSS IN COLLECTION EFFICIENCY AS A FUNCTION
OF POWER RATE FOR TESTS WITH LIMESTONE
INJECTION 89
FIGURE 25 - PREClPlT/iTION RATE PARAMETER AS A FUNCTION
OF POWER DENSITY FOR TESTS WITH LIMESTONE
INJECTION (GAS TEMPERATURE AND LIMESTONE
PARTICLE SIZE ARE IDENTIFIED SEPARATELY). ... 92
FIGURE 26 - PARTICLE SIZE ANALYSES OF LIMESTONE FEED
SAMPLES USED IN SECOND CES TEST SERIES .... 95
FIGURE 27 - PARTICLE FJHB ANALYSES OF MECHANICAL
COLLECTOR INLET SAMPLES WITHOUT LIMESTONE
INJECTION (TESTS 1A, IB, 3A, 4A, 5A, 5B). . . . ]01
FIGURE 28 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PRKCIPITATOR INLET SAMPLES WITHOUT LIMESTONE »
INJECTION (TESTS 3A, '1A, 4B, 5A, 5B) 102
FIGURE 2S) - PARTICLE SEZE ANALYSES OF ELECTROSTATIC
PRECIP1TATOR OUTLET SAMPLES WITHOUT LIMESTONE
INJECTION (TESTS 2A, 3A, 3D, 413) 1C3
FIGURE 30 - PARTICLE SIZE ANALYSES OF MECHANICAL HOPPER
SAMPLES WITHOUT LIMESTONE INJECTION (TESTS 1A,
113, ?A, 3A, 4A, 5A, !5B) 104
FIGURE 31 - PAP.TICLE SIZE ANALYSE!! OF ELECTROSTATIC
fJRKC.n>lYATOK HOPPER SAMPLES WITHOUT LIMESTONE
INJECTION (TESTS 3 A, IB, 2A, 3A, 4A, 5A, 5B) . . 105
-------
TAB),I.-: OF COMTUHTS (Continued}
LIST OF FIGURES
FIGURE 32 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PRECIPI7ATOR INLET S7vHPLES WITHOUT LIMESTONE
INJECTION (TESTS 16, 19, 20, 21, 22) 106
FIGURE 33 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PKECIPTTATOR HOPPER SAMPLES WITHOUT LIMESTONE
INJECTION (TESTS 16, 21, 22) 107
FIGURE 34 - PARTICLE SIZE ANALYSES MECHANICAL COLLECTOR
INLET SAMPLES WITH COARSE LIMESTONE IN-
JECTION (TESTS 14, 15, 32, 33) 108
FIGURE 35 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PRECIPITATOR INLET SAMPLES WITH COARSE LIME-
STONE INJECTION (TESTS 10, 11, 14, 15, 25, 32,
33) : 109
FIGURE 36 - PARTICLE SIZE ANALYSIS OF ELECTROSTATIC
PRECIPITATOR OUTLET SAMPLES WITH COARSE
LIMESTONE INJECTION (TESTS 11, 14) 110
FIGURE 37 - PARTICLE SIZE ANALYSES OF MECHANICAL
COLLECTOR HOPPER SAMPLES WITH COARSE LIME-
STONE INJECTION (TESTS 14, 15, 32, 33) Ill
FIGURE 38 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PRECIPITATOR HOPPER SAMPLES WITH COARSE
LIMESTONE INJECTION (TESTS 14, 15) 112
FIGURE 39 - PARTICLE SIZE ANALYSES OF MECHANICAL COLLECTOR
INLET SAMPLES WITH FINE LIMESTONE INJECTION
(TESTS 2, 3, 5, 6, 8) ' . . 113
FIGURE 40 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PRECIPITATOR INLET SAMPLES WITH FINE LIMESTONE
INJECTION (TESTS 2, 3r 4, 5, 6, 8, 17, 18, 23,
24, 26, 27, 28, 29, 30) 114
FIGURE 41 - PARTICLE SIZE ANALYSES OF ELECTROSTATIC
PRECIPITATOR OUTLET SAMPLES WITH FINE
LIMESTONE INJECTION (TESTS 2, 3, 4, 5, 6, 23,
24, 26) 115
FIGURE 42 - PARTICLE SIZE ANALYSES OF MECHANICAL COLLECTOR
HOPl'ER SAMPLES WITH FINE LIMESTONE INJECTION
(TESTS 2, 3, 5, 6, 8) 116
-------
TAP,],).; OF CONTENTS (Continued)
LIST OF FJ.OURES
FIGURE 43 - PARTICLE SlZf. ANALYSIS OF ELECTROSTATIC
PRECiPIT/'TOR HOPPER SAMPLES VITH FINE
LIKESTOKE INJECTION (TESTS .17, 18, 23, 24) . . . 117
FIGURE 44 - FRACTIONAL EFFICIENCY CURVE FOR MECHANICAL
COLLECTOR ................... 122
FIGURE 45 - FRACTIONAL EFFICIENCY CURVES FOR
ELECTROSTATIC PRECIPITATOR ........... 123
FIGURE 4G -- ELECTROSTATIC PKL'CIPITATOR PART1CULATE INLET
LOADING AS A FUNCTION OF LIME STONE FEEDRATE . . 128
FIGURE 47 - IN-SITU RESISTIVITIES OBTAINED ON FULL-SCALE
AND PILOT SCALE PULVERIZED COAL-FIRING
BOILERS WITHOUT LIMESTONE INJECTION ...... 131
FIGURE 48 -- IN-SITU RESISTIVITIES OBTAINED ON FULL SCALE
AND PILOT SCALE PULVERIZED COAL FIRING BOILERS
WITH LIMESTONE 3NJPICTDON ............ 132
FIGURE 49 - IN-SITU RESISTIVITY DATA OBTAINED BY K.J. McLEAN
AT TVA S11A17NEE STATION, BOILER S10 DURING THE
CES SECOND TEST SERIES ............. 134
FIGURE 50 - RESISTIVITY OF FLY ASH SAMPLES FROM VARIOUS
COALS FIRED IN PILOT PLANT OF B&W ....... 136
FIGURE 51 - IN-SITU AND LABORATORY RESISTIVITIES FOR
REACTED ADDITIVE-FLY ASH SAMPLES FROM B&W
PILOT PLANT .................. 136
i
FIGURE 52 - IN-SITU AND LABORATORY RESISTIVITIES FOR
REACTED ADDITIVE-FLY ASH MIXTURES FROM B&W
PILOT PLANT .................. 337
1'IGURU 53 - IN-SITU AMD LABORATORY RESISTIVITIES FOR
REACTED ADDITIVE-FLY ASH MIXTURES FROM B&W
PILOT PLANT .................. 137
FIGURE 54 - LABORATORY RESISTIVITY MEASUREMENTS OF
PRECIPITATOR INLET SAMPLES AS A FUNCTION OF
GAS TEMPERATURE WITHOUT LIMESTONE INJECTION . . 138
FIGURE 55 - LABORATORY RESISTIVITY MEASUREMENTS ON
PRL'CIPITATOR INLET SAMPLES AS A FUNCTION OF
GAS TEMPERATURE WITH LIMESTONE INJECTION .... 139
FIGURE 56 - IN-SITU KKS15JT3 VJ'i'V VS. TEMPERATURE
RELATIONS!! I P FOU VARIOUS COAL SULFUR (NO
L.1 ME STONE INJECT JON) .............. 142
-------
T.AKT.E OF CONTENTS (Continued)
LIST OF FIGURES
FIGURE 57 - TN-SITU RESISTIVITY VS. TEMPERATURE
RELATIONSHIP FOR VARIOUS COAL SULFURS (WITH
LIMESTONE INJECTION) .............. 144
FIGURE 58 - APPROXIMATE PRECIPITATION RATE PARAMETER VS.
RESISTIVITY RELATIONSHIP WITHOUT AMD WITH
LIMESTONE INJECTION .............. 145
FIGURE 59 - CALCIUM OXIDE AT ELECTROSTATIC INLET AS A
FRACTION OF LIMESTONE FEEDRATE TO THE BOILER . . 150
FIGURE 60 - PARTICLE RESISTIVITY AS A FUNCTION OF THE
CaO/S RATIO AT THE PRECIPITATOR INLET ..... 152
FIGURE 61 - SIMPLIFIED SYSTEM DIAGRAM OF THE RESEARCH
COTTRELL, INC. PROPRIETARY OPTICAL SENSOR ... 154
FIGURE 62 - DATA OBTAINED ON PARTICULATE LOADING USING
AN OPTICAL MONITOR .............. 157
FIGURE 63 - TYPICAL OPTICAL SENSOR CHART ON SHAWNEE #10
BOILER ("B" SIDE) WJTH AND WITHOUT LIMESTONE
INJECTION ................... 159
FIGURE 64 - TYPICAL PRECIPITATOR VOLTAGE VS. CURRENT
CHARACTERISTIC ................. 177
FIGURE 65 - TYPICAL PRECIPITATOR ENERGIZATION ARRANGEMENTS . 182
-------
TABLE OF C03TE11TS (Continued)
aqe
LIST OF TABLES
TABLE I COMPLSVZD TESTS (FIRST CAMPAIGN) CONTRACT
CPA ?y.~69"139 36
TABLE II COMPLETED TESTS (SECOND CAMPAIGN) CONTRACT
CPA 22-69-139 MODIFICATIONS 6 AND 7 37
TABLE III SUMMARY OF THE TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S FIRST TEST SERIES ... 40
TABLE IV SUMi-'-ARY OF TEST DATA FROM THE COTTRELL
ENVIKOKriUSiTAL SYSTEM'S FIRST TEST SERIES ... 41
TABLE V SUMMARY OF TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S FIRST TEST SERIES ... 42
TABLE VI SUMMARY OF TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES . . 43
TABLE VII SUMtfAE* OF TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES . . 44
TABLE VIII SUMMARY OF TEST DATA FROM TVA'S FIRST TEST
SERIES 45
TABLE IX SUHKARY OF TEST DATA FROM TVA'S FIRST TEST
SERIES 46
TABLE X SUMMARY OF TEST DATA FROM TVA'S SECOND
TEST SERIES 47
TABLE XI SUMMARY OF TEST DATA FROM TVA'S SECOND
TEST SERIES 48
TABLE XII SUMMARY OF TEST DATA FROM TVA'S SECOND
TEST SERIES 49
TABLE XIII SUMMARY OF TEST DATA FROM TVA'S SECOND
TEST SERIES 50
TABLE XIV SUMMARV OF TEST DATA FROM TVA'S SECOND
TEST SERIES 51
TABLE XV SUMMARY OF TEST DATA FROM TVA'S SECOND
TEST SERIES 52
TABLE XVI COAL ANALYSES FOR BOTH COTTRELL ENVIRONMENTAL
SYSTEM'S TEST SERIES 53
TABLE XVII COAL ANALYSES FOR TVA'S FIRST TEST SERIES . . 54
TABLE XVIII COAL ANALYSES FOR BABCGCK AND WILCOX PILOT
TEST PROGRAM 55
-------
TABLE OF CONTENTS (Continued)
LIST OF TABLES
p:ige
TABLE XIX
TABLE XX
TABLE XXI
TABLE XX Jl
TABLE XXIII
TABLE XXIV
TABLE XXV
TABLE XXVI
TABLE XXVII
TABLE XXVIII
TABLE XXIX
TABLE XXX
TABLE XXXI
TABLE XXXII
TABLE XXXIII
TABLE XXXIV
TABLE XXXV
PARTICLE SIZE ANALYSES FOR COTTRELL ENVIRONMENTAL
SYSTEM'S FIRST TEST SERIES
PARTICLE SIZE ANALYSES FOR COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES . . .
PARTICLE SIZE ANALYSES FOR COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES . . .
PARTICLE SIZE ANALYSES FOR COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES . . .
LABORATORY AND IN-SITU RESISTIVITY MEASUREMENTS
FOR COTTRELL ENVIRONMENTAL SYSTEM'S FIRST TEST
SERIES
LABORATORY AND IN-STTU RESISTIVITY MEASUREMENTS
FOR COTTRELL ENVIRONMENTAL SYSTEM'S SECOND
TEST SERIES
LABORATORY AND IN-SITU RESISTIVITY MEASUREMENTS
FOR COTTRELL ENCIRONMENTAL SYSTEM'S SECOND
TEST SERIES '
LABORATORY AND IN-SITU RESISTIVITY MEASUREMENTS
FOR BABCOCK AND WILCOX PILOT TEST PROGRAM . . .
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON
SAMPLES TAKEN DURING THE FIRST CES TEST SERIES .
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON
SAMPLES TAKEN DURING THE SECOND TEST SERIES. . .
CHEMICAL ANALYSES OF LIMESTONE USED DURING
SECOND CES TEST SERIES
SUMMARY OF TEST DATA USED IN CORRELATIONS
FRACTIONAL EFFICIENCY OF DUST COLLECTORS -
FLY ASH ONLY
FRACTIONAL EFFICIENCY OF DUST COLLECTORS -
FIN1? LIMESTONE
FRACTIONAL EFFICIENCY OF DUST COLLECTORS -
COARSE LIMESTONE
SUMMARY OF PARTICLE SIZE ANALYSES ON
SAMPLES FROM BOTH CES TEST SERIES .
IN-SITU RESISTIVITY DATA OBTAINED BY SOUTHERN
RESEARCH INSTITUTE AT TVA SHAWNEK STATION,
BOILER JI10 DURING THE CES SECOND TEST SERIES .
56
57
58
59
60
61
62
63
64
65
69
94
119
120
121
125
13 J
-------
TABLE OF CONTENTS (Con(:j nuod)
LIST OF TAHLKE
pacje
TABLE XXXVI DATA SUMMARY - FUL3, SCALE DOLOMITE
INJECTION TfiST RESULTS OBTAINED BY
RESEARCH COTTRELL, INC. AT A LARGE
MIDWEST UTILITY 135
TABLE XXXVIT DATA USJ'JD FOR RELATIONSHIP BETWEEN
PRECIPITATION RATE PARAMETER AND PARTICIPATE
RESISTIVITY 146
TABLE XXXVIII SUMMARY OF DATA USED TN SECTION ON CHEMICAL
ANALYSES (PPS. 147-lb3) 148
TABLE XXXIX DATA '.'AKEil FROM THE OPTICAL SENSOR RECORDER
CHARTS 156
TABLE XL SUMMARY OF 1970 TVA TEST RESULTS USED IN
ESTABLISHING BASELINE BOILER AND PARTTCULATE
COLLECTOR OPERATING PARAMETERS FOR NO
LIMESTONE INJECTION 167
TABLE XLI SUMMARY OF ELECTROSTATIC PRECIPITATOR SIZE
MODIFICATIONS AND COSTS FOR THE PRESENTLY
INSTALLED DUST COLLECTING SYSTEM REQUIRED
TO MAINTAIN A STACK EMISSION RATE EQUIVALENT
TO BASELINE NO LIMESTONE INJECTION 170
TABLE XLII SUMMARY OF THE "HOT" PRCCIPITATQR SIZING
AND COSTING FOR SHAWNEE STATION BOILER #10
WITH AND WITHOUT LIMESTONE INJECTION
(STRAIGHT PRECIPITATOR) 172
TABLE XLTI1 SUMMARY OF GAS COOLING AS AN OPTION FOR
COARSE OR FINE LIMESTONE INJECTION 174
-------
-1-
I. INTRODUCTION
This report is submitted as a partial fulfillment of the re-
quirements for Environmental Protection Agency (EPA) Contract
CPA 22-69-139 and presents the results of a full-scale study
to quantify the operation of a combination mechanical collec-
tor electrostatic precipitator dust collection system with
and without dry limestone injection. This study is part of
the overall program being undertaken at the Shawnee power
generating station of the Tennessee Valley Authority for the
control of sulfur oxide emissions from a full-scale utility
boiler. Definition of the effects of dry additive injection
on the particulate control equipment operation and the recom-
mended system modifications, including cost benefit data to
maintain stack particulate emissions with injection equivalent
to that of 2.7% sulfur and 10% ash coal-firing without in-
jection are the primary requirements of this study. A further
requirement is to recommend investigative programs to be con-
sidered for future study.
Two test campaigns were conducted by Cottrell Environmental
Systems, Inc. during this study:
The first occurred in December, 1969 and related to
the quantification of the dust collection system per-
formance without additive injection. The main pur-
pose of the data acquisition was for use as a base-
line in defining the effects of subsequent additive
injection;
-------
-2-
The second was in July, 1971 during limestone in-
jection and consisted of controlling four parameters
at two levels which included two boiler variables
(coal sulfur and flue gas temperature), and two
limestone injection variables (amount and particle
size).
The data and samples from these tests and other pertinent
(1-5)*
sources, i.e. Tennessee Valley Authority, Southern Re-
search Institute, Research-Cottrell, Inc., Babcock and Wilcox,
Co., and Dr. K. J. McLean, EPA visiting associate from Wol-
longong University, Australia, have been analyzed and corre-
lated. The results are contained in subsequent sections of
this report.
* The numbers in superscript refer to the bibliography at
the end of the text.
-------
-3-
II. TECHNICAL APPROACH
Because of the chemical and physical properties of the in-
jected additive material, the characteristics as well as
the quantity of particulate to be collected will vary sub-
stantially. These variations, including the degree of affect
on the operating parameters of the dust collection system,
must be monitored and evaluated in order to size and cost
the system. The changes in particulate loading, specific
gravity and particle size distribution will affect the per-
formance of the mechanical colelctors which precede the
electrostatic precipitator. This in turn will vary the
quantity and nature of the dust entering the precipitator,
resulting in operational changes. Of particular significance
will be the change in the electrical conductivity of the dust
caused mainly by the removal of sulfur trioxide from the flue
gas by the alkaline additive and the higher bulk resistance
of limestone.
In the collection of fly ash-limestone reaction products by
an electrostatic precipitator, the most critical parameter
is the bulk electrical resistivity of the particulate. Values
above 10 to 10 ohm-cm result in reduced electrical power
to the precipitator and poor performance. This particular
f 6 9)
subject has been treated extensively in the literature
and will be covered in more detail in subsequent sections of
-------
-4-
this report. A comparison of present results with past
experience will also be discussed.
The main operational parameters that were monitored during
the test program include:
1. Particulate Characteristics (Fly Ash, Fly Ash-
Limestone Reaction Products)
(a) Specific Gravity
(b) Particle Size Analysis (Bahco and Sieve)
(c) Bulk Electrical Resistivity (Laboratory)
(d) In-Situ Electrical Resistivity
(e) Chemical Analysis
(1) Loss on Ignition
(2) 8^2, A1203, Fe203, CaO, MgO, Ti02
Na20, K20, S04=, S03=, S=
2. Collector Variables
(a) Particulate Loadings Inlet and Outlet
(ESP and MC)
(b) Pressure Drop of Mechanical Collector
(c) Current-Voltage Characteristics of ESP
(d) Sparking Rate of ESP
(e) Particulate Collection Efficiency (ESP
and MC)
3. Boiler Variables
(a) Flue Gas Analysis (02, S02, H20)
(b) MW Load, Steam, Air
(c) Flue Gas Temperature, Pressure
(d) Gas Volume
(e) Coal-Firing Rate
(f) Limestone Addition Rate
-------
4. Additive Characteristics
(a) Particle Size Analysis (Bahco and Sieve)
(b) Electrical Resistivity (Laboratory)
(c) Chemical Analysis
(1) CaO, MgO, Fe0 , Si0
5. Coal Analysis
(a) Sulfur
(1) Pyritic
(2) Organic
(3) Sulfate
(b) Ash
(c) Moisture
The objective of the test program was to provide an assessment
of the particulate collecting system with and without additives
for use in establishing the additional gas cleaning equipment
required to maintain stack particulate emissions at levels
associated with 2.8% sulfur 15.5% ash coal-firing. In addi-
tion, other alternatives such as gas cooling, hot precipi-
tator, gas conditioning, and type of electrical energization
were evaluated.
-------
-6-
III. TEST METHODS
The test methods used were in compliance with the ASME-
PTC 27 and ASME-PTC 28 with regard to determining gas
volume, particulate loading and analyzing the collected
material.
1. Gas Velocity Measurements are required to obtain the
necessary data for determining:
(a) Total gas volume being treated by the dust
collector.
(b) Distribution and flow pattern of gas enterincr
the collector.
(c) The sampling rates required to obtain represen-
tative particulate loadings entering and
leaving the collector.
The equipment used to make these measurements during
the test program reported herein is shown schematically
in Figure l(a). It consisted of a Stauscheibe pitot
tube with inclined draft gauge for velocity head
readings, plus a thermocouple and potentiometer for
simultaneous temperature measurements.
The gas velocity was calculated from the equation:
TD h"
v = 15.6 k = 13.37
-------
-7-
Where,
v = Gas Velocity - FPS
TD = Duct Temp. °F + 460-°R
h = Velocity Head - "H20
P = Duct Pressure - "Hg
= Barometric pressure +_
Duct Static Pressure ("H?Q)
13.6
k = 0.855 = Stauscheibe pitot tube
p factor
15.6 = Constant for flue gas from
pulverized coal combustion.
The total gas volume was calculated from the equation:
V = 60 Av (2)
Where,
V = Total Gas Volume - ACFM
A = Flue Cross-Sectional Area Where
Velocitv Traverse Made - Ft^
v = Average gas velocity obtained
from traverse - FPS
60 = seconds/minute
2. Moisture Content of the gas was determined bv hot-gas
psychrometry which involves determining the wet and drv
bulb temperatures of the gas. The following equations
are used to calculate the moisture content:
e = e1 - 0.01 (td-tw), and (3)
-------
-8-
Where,
e = Vapor pressure of qas - "Hg
e^ = Vapor pressure of saturated gas
at tw - "Hg
t
-------
FIGtt... 1
EQUIPMENT FOR MAKING GAS VELOCITY MEASUREMENTS
AND TAKING PARTICULATE SAMPLES
Stauscheibe
Pitot Tube
Thermocouple
(a)
Manometer
Sample
rNozzle and
Probe
Cyclone
With Glass
Jar Hopper
Inclined
Draft Gauge
Potentiometer
Inclined
Draft Gauge
Dial Thermometer
Bag Filter
Exhaust Fan
Control
j>' Valve
Gas
Outlet
i
vo
I
-------
-10-
The total cubic feet of gas sampled was calculated from
the equations:
Vp = 3930 AA kp
(6)
(7)
Where,
V = Volume sample rate at each
traverse point - CFM
2
A = Sample nozzle area - Ft
k = 0.855 = Stauscheibe pitot tube
p factor
Tg = Sample train temperature - °R
T = Duct temperature - °R
hp = Velocity head at each sample
point - "H2O
V = Total volume sample rate - CFM
N = Number of sample points
V_ = Total volume sampled - Ft @
b 70 F and 30" Hq
B = Barometric pressure - "Hq
t = Samplinq time at each point -
minutes
3930 = Calibration constant of cyclone orifice
-------
-11-
The amount of particulate collected was determined by
drying and reweighing the cvclone sampler jar and
filter bag. The particulate loading was calculated
using the equation:
D = C .
VS
Where,
D = Particulate loading - grains/Ft @
70 F and 30"Hg
D_ = Net weight of particulate
collected - grams
Vq = Total volume sampled - Ft @
70 F and 30 "Hg
15.43 = Conversion factor, grains to arains
The efficiency of the collector was determined bv the
equation:
Where ,
E = Efficiencv - %
D_ = Inlet particulate loading -
grains/Ft^
DO = Outlet particulate loading -
grains/Ft3
4. Test Sections were located in areas of reasonably straight
runs of duct work and free of interference from nearby
equipment. Figure 2 is a schematic diagram of the boiler,
-------
Primary
Reheater
Superheaters
a
Electrostatic
Precipitator
Stack
Optical
Sensor
ID
Fan
Precipitated
Outlet \
Sample Station\
(See Fig.5)
A/V
Mechanical ^
Outlet Sample
Station
Mechanical
Collector
(See Fig.4)
Limestone
Injection
Ports
to
i
urners
Mechanical Inlet
Sample Station
(See Fig.3)
FD Fan
FIGURE 2
SCHEMATIC DIAGRAM OF BOILER #10 SHAWNEE STATION, TVA
-------
-13-
collectors, and associated eauipment showing the location
of the sampling areas. Figures 3 through 5 detail the
actual dimensions and number of sample points used at
the mechanical collector inlet and the electrostatic
precipitator inlet and outlet.
5. In-Situ Resistivity measurements were made using a
portable apparatus (Figure 6) designed and supplied bv
Research-Cottrell, Inc. The apparatus measures the
electrical resistance of a layer of dust precipitated
from flue gas under actual operating conditions. It
consists of a small electrostatic point-plane precioitator
(Figure 7), an iron constantan thermocouple located near
the plane, and a control unit for supplying power and
measuring voltage and current.
6. The Laboratory Resistivity measurements were made in
apparatus shown photographically and schematically in
Figures 8 and 9. The cell shown in ^igure 10 is mounted
in an electrically heated and thermostatically controlled
chamber capable of reaching temperatures in the 650°F
range. In addition, humidity can be controlled from
bone dry up to 30 or 40% bv volume. The schematic
electrical circuitry is shown in Figure 11.
-------
-14-
Duct Area = 72.6 Ft'
(each side)
Bottom
"A" Side
Cyclone
Take off at*
Two Elevations
As Shown Above
Boiler
Centerline
Gas
Flow,
3'-3 3/8"
From
Air Heater
Gas
' F10W
Cyclone
Mechanicc
Collectoi
\
Hopper
Cyclone Boiler
Flange Duct
Flange
FIGURE 3
DETAILS OF MECHANICAL COLLECTOR
INLET SAMPLING STATION
-------
-15-
2'-5"
H- -H
4- 4-
4- H- + +
4-
4- 4- -h
Duct Area=204Ft
-f
-1- 4-
4- 4-
4- 4-
t- 4-
17'-1/2"
FIGURE 4
DETAILS OF MECHANICAL COLLECTOR
OUTLET - ELECTROSTATIC PRECIPITATOR INLET
SAMPLING STATION
-------
-16-
'-3 3/
21 _9 ii
^
4-
TT TT
TT TT
t-
-h + -t
Duct Area=147.
t f
13'-1/2"
t -4- t +
-t- +
t
t
T
2 i_
FIGURE 5
DETAILS OF 'ELECTROSTATIC
PRECIPITATOR OUTLET SAMPLING STATION
-------
FIGURE 6
IN-SITU RESISTIVITY APPARATUS
POWER SUPPLY AND METERING UNIT
AND POINT-PLANE CELL
-------
-18-
Flue Gas & Dust
Flow Direction
Thermocouple
i Corona Point
FIGURE 7
POINT-PLANE KESISTIVITY CELL
-------
FIGURE 8 - LABORATORY RESISTIVITY MEASURING APPARATUS
-------
-20-
Water
Reservoir
Pressure
Equalizing Tube
Needle Valve'
Sight Glass
Heaters
Manometer
Conductivity
Cell
Air Heater Duct
Rotameter
Air Supply
5-10 PSIG
Dryers
FIGURE 9
SCHEMATIC DIAGRAM OF LABORATORY
RESISTIVITY MEASURING APPARATUS
-------
-21-
FIGURE 10
CROSS-SECTION DIAGRAM OF
MEASURING CELL USED IN LABORATORY
RESISTIVITY APPARATUS
Measuring
Electrode
Air Flow
With Controlled
Moisture
Sintered Metal
Disc
High Voltage
Electrode
FIGURE 11
SCHEMATIC OF ELECTRIC CIRCUIT
FOR LABORATORY RESISTIVITY APPARATUS
Current Meter
Dust
Conductivity
Cell
^Voltmeter
H-V
Rectifier
0-15KV
-------
-22-
7. The skeletal or true density of the particulate samples
was determined by the pycnometer method. Approximately
a 5-gram sample is transferred to a weighed pycnometer
bottle of known volume and reweighed. The bottle is
half filled with a suitable liquid (selected on the basis
of dust solubility being a minimum) and placed in a dessi-
cator-type container which can be evacuated (see Figure 12).
After all air has been removed from the dust sample, the
pycnometer bottle is filled to capacity, thermally
equilibrated and reweighed. The dust density is calculated
as follows:
W -W
vi - -Irr1
_
d ~
p ~ V=V (ID
Where,
W = Weight of pycnometer bottle - grams
W_ = Weight of pycnometer + dust - grams
W, = Weight of pycnometer + dust +
liquid - grams
V, = Volume of liquid - cubic centimeters
V = Volume of pycnometer - cubic
" centimeters
d, = Density of liquid - grams/cubic
centimeters
d = True density of dust - grams/cubic
" centimeters
-------
-23-
To Vacuum
Source
Dessicator
Pycnometer
Bottle
FIGURE 12
APPARATUS FOR MEASURING SKELETAL
OR TRUE DENSITY OF PARTICULATE
-------
-24-
8. The particle size distributions were made by sieve and
Bahco methods. A set of 3 inch U.S. Standard sieves and
pan are weighed. The sieves are then nested reading 50~
mesh (297 microns), 100-mesh (149 microns), 200-mesh (74
microns), 325-mesh (44 microns) and pan from top to bottom.
About a 2 gram sample of dried dust is placed on the top
sieve and covered. The set of sieves is then placed in a
Ro-tap and shaken for twenty minutes. The sieves are
brushed lightly and reweighed. The weight of fractions
is obtained by difference and final results are calcu-
lated as "percent fraction separated" and reported as
"cumulative percent finer".
The Bahco method of sub-sieve particle sizing uses a cen-
trifugal classifier (see Figure 13) which operates at
3500 RPM. The sample is introduced into a spiral-shaped
air current flowing toward the center. Depending on the
size, weight and shape of the particles, a certain
fraction is accelerated by centrifugal force toward the
periphery of the whirl, while the remainder is carried
toward the center. By varying flow through the use of
throttles, the dust sample can be divided into a number
of fractions between about 2 and 30 microns. This particu-
lar method is not absolute but must be calibrated with a
standard sample of known distribution based on an absolute
method.
-------
FIGURE 13
BAHCO CENTRIFUGAL PARTICLE CLASSIFIER
1 Rotor Casting
2 Fan
3 Vibrator
4 Adjustable Sl'ide
5 Feed Hopper
6 Revolving Brush
7 Feed Tube
8 Feed Slot
9 Fan Wheel Outlet
10 Cover
11 Rotary Duct
12 Feed Hole
13 Brake
14 Throttle Spacer
15 Motor - 3520 RPM
16 Grading Member
17 Threaded Spindle
18 Symmetrical Disc
19 Sifting Chamber
20 Catch Basin
21 Housing
22 Radial Vanes
-------
-26-
9. The stack opacity was monitored by means of an optical
sensor designed and supplied by Research-Cottrell, Inc.
A schematic diagram of the system is shown in Figure 14.
A light source and optical sensor are contained in sealed
housings mounted on opposite sides of a duct. Sufficient
sensitivity and flexibility are provided to permit full
scale recorder calibration corresponding to 20 up to 100%
optical obscuration for aerosol paths ranging from 6 to
30 feet. (20% is a No. 1 Ringelmann and 100% a No. 5
Ringelmann). Normally, a 0-5 Ringelmann scale calibration
is used to encompass peak emission periods such as soot-
blowing .
A clean gas reference signal is continually compared with
the dirty gas signal by means of a differential signal
amplifier whose signal is recorded continually as optical
density readout.
10. Coal Analyses were provided by Smith, Rudy and Company,
chemists in Philadelphia, Pennsylvania while other chemical
analyses of particulate samples were performed by the TVA
laboratory chemists located in Chattanooga, Tennessee.
-------
Dirty Gas Signal
Removable
Window
Optical Sensor (Meas.)
Measuring Beam
-~ Induced Air Purge
Flue or Stack
Differential
Signal Amplifier
Removable
Window
'.'. - v
-I
Induced Air Purge
Optical Sensor (Ref)
~\ Clean Gas Ref. signal
Light
Source
Reference Beam
Voltage
Regulator
Optical Density Readout
ill
Regulated
Power Supply
Isolation Transformer
Electrical Input
115 V. 50/60 Hz
to
FIGURE 14
FUNCTIONAL DIAGRAM OF THE OPTICAL SENSOR
-------
-28-
IV. TEST CONDITIONS AND PROCEDUKliS
The initial test campaign without additive injection was
conducted with a boiler generated load of about 140 mega-
watts with very little variation. No attempt was made
to control the coal sulfur. Soot-blowing was curtailed
during the tests. Mechanical and electrical precipitator
hoppers were emptied at the beginning and end of each test
period at which time samples were taken. This procedure
ensured representative hopper samples. Both "A" and "B"
precipitators of boiler No. 10 were tested during this
campaign. (See Figure 15 for schematic diagram of elec-
trostatic precipitator). Coal feed rates and samples were
obtained by monitoring and grab-sampling the coal feeders.
Boiler conditions were recorded from the control room panels
Main operating difficulties encountered were with the
electrostatic precipitators in the form of short circuits
caused by broken discharge electrodes.
The second test series was conducted with and without
additive injection. Boiler generated load was difficult
to control because of external conditions of low water
level in the river supplying the condensers. As a result,
load varied from 125 MW to 148 MW during the test period.
-------
FIGURE 15
SCHEMATIC DIAGRAM OF ELECTROSTATIC PRECIPITATOR
ARRANGEMENT AND ELECTRICAL HOOK-UP
Optical
Sensor
Electrical Sets
Full Wave Hook-up
^ H^ _£
Electrical
Sets
Full Wave Hook-up
VO
I
Gas Flow
From Boiler No. 10
-------
-30-
Extreme ambient temperature conditions at the mechanical
collector inlet sampling station (160-180 F.) caused
equipment failure and hampered the sampling personnel.
The sampling equipment was revised by inserting a flexi-
ble hose between the sampling probe and the Aerotec Sam-
pler. This allowed placement of the sampler in a somewhat
cooler location.
The limestone feeder tripped-off at high feed rates. This
was finally resolved by air-cooling the feeder motor. The
electrostatic precipitator transformer-rectifier controls
were erratic in operation. The silicon controlled rectifier
firing circuit was too sensitive to sparking which caused
the precipitator voltage to be lowered at the first occurence
of sparking rather than at an optimum rate. The problem
was solved by replacing faulty resistors in the control
circuit.
As shown in Figure 15, the "A" and "B" side of the electro-
static precipitator are electrically interconnected. For
the tests where temperature on the "B" side was reduced to
about 250 F. by fan biasing, the "A" side gas temperature
would rise to over 350 F. This meant that the "A" side
dust resistivity could influence the operation of the "B"
side portion of the electrostatic precipitator. This
-------
-31-
interference was corrected by deenergizing the "A" side and
using the electrical sets to energize only the "B" side.
Soot blowing, condenser repairs, and hopper enptying took
more time than originally anticipated and modifications in
test and operating procedures were instituted. In order
to complete as much of the statistically designed test pro-
gram as possible within reasonable cost and schedule con-
straints, the following changes in procedure were agreed
upon:
1. The velocity and temperature traverses before
each test were eliminated. The gas tempera-
ture and pressure drop of the mechanical
collector were adjusted by fan biasing to
give the desired test conditions at the
electrostatic precipitator inlet. Previous
velocity and temperature traverses at similar
mechanical collector conditions (temperature
within 5°F and pressure drop within 10%)were
then used to obtain isokinetic sampling.
Figures 16 to 18 are representative tempera-
ture and velocity traverses for the three
sampling stations.
-------
-32-
2. Elimination of sampling at the mechanical
inlet for most tests allowed the use of these
two samplers, one each, on the ESP inlet and
outlet or a total of three samplers at each
of these locations. Time per test was thus
reduced to 50 minutes from 75 minutes thereby
improving test scheduling without reducing
the amount of dust collected.
Tables I and II list the completed tests for both campaigns,
-------
PICA. £ 16
REPRESENTATIVE TEMPERATURE AND VELOCITY TRAVERSE
TOP , ^
Avy. Velocity - 60.4 FI
Avg. Temperature =
ACf-'M of Gas - (60.4) (7:
Pol torn 31
AT THE MECHANICAL COLLECTOR INLET ("B" SIDE!
TT TT
61.2 54.8
4 4
310 F 315 F
65.2 57.3
4 -H
318 F 312 F
>S
2,6) (60) = 263,157
6'<.J 57.3
H- -i-
330 F 314 F
60.? 61.?
4 -f-
3J4 F 3J1 F
LI r "
" ' rr
61.2 66.3
4 4
312 F 308 F
58.7 63.1
-1- -1-
315 F 312 F
60.1 61.1
4- -r
3] 8 F 315 F
57.4 58.2
4 4
310 F 308 F
j
-------
-34-
FIGURE 17
REPRESENTATIVE TEMPERATURE AND VELOCITY TRAVERSE AT THE MECHANICAL
OUTLET - PRECIPITATOR INLET SAMPLE STATION ("B" SIDE)
1=
"
1=
t
t
t
19.2
-h
293F
18.5
293F
15.3
h
298F
15.3
4-
305F
15.3
4-
311F
13.7
311F
21.5
295F
19.2
298F
19.3
298F
21.6
311F
21.6
315F
19.4
313F
21.5
295F
19.3
298F
19.3
296F
24.6
311F
24.6
315F
19.4
313F
15.2
4
293F
19.2
293F
15.3
296F
21.6
-h
311F
21.6
313F
21.6
313F
11.8
293F
19.2
293F
19.3
4-
298F
19.4
307F
19.4
313F
19.4
311F
Avg. Velocity =19.1 FPS
Avg. Temperature = 303F
ACFM of Gas = (19.1) (204) (60) = 233,784
-------
-35-
FIGURE 18
REPRESENTATIVE TEMPERATURE AND VELOCITY TRAVERSE AT THE
PRECIPITATOR OUTLET SAMPLING STATION ("B" SIDE)
JEL
' '
33.5
4-
273F
34.0
4-
291F
34.1
4-
297F
34.0
4-
293F
34.0
+
291F
26.1
4-
277F
26.1
-1-
277F
34.0
4-
293F
30.4
4-
291F
32.6
4-
291F
21.4
+
287F
21.5
-h
291F
26.4
4-
297F
24.7
4-
299F
30.5
+
297F
21.1
+
264F
26.1
+-
278F
28.8
h
293F
26.4
4-
301F
28.9
+
297F
21.1
4-
267F
24.7
-h
303F
30.5
4-
299F
32.8
+
301F
32.8
-h
305F
20.8
4-
243F
26.1
4-
277F
32.8
4-
303F
32.6
h
293F
28.9
-1-
301F
Avg. Velocity = 28.C FPS
Avg. Temperature = 2'C9F
ACFM of Gas = (28.6) C;47.1) (60) = 252,424
-------
-36-
TAB1J: I
COMPLETED TESTS (FIRST CAMPAIGN)
CONTRACT CPA 22-69-139
Test
Number
1A*
IB*
2A
3A*
3B*
4A*
4B*
5A*
. SB*
Additive Stoich.
XT
0
0
0
0
0
0
0
0
0
Gas Temp.
x?
+
+
+
+
+
+
+
+
+
Particle Size
XT
0
0
0
0
0
0
0
0
0
% S in Coal
Xa
+
+
+
-
-
+
-
*
+ .
Date
Perfoi-med
12/11/69
12/11
12/12
12/14
12/13
12/14
12/13
12/15
12/15
KEY:
LEVEL
+
-
X2
289-318
238-256
X4
2.30-4.10
1.00-2.29
* Mechanical Collector Inlet Sample Taken
-------
-37-
TABI.h II
COMPLETED Fl.STS (SI'COXI) CAMPAIGN)
CONTRACT CPA 22-69-139 MODI I' ICAT ION'S 6 & 7
Test
Humbcr
1
2*
3*
4«
5*
6*
8*
9
10
11
. 25
19
20
21
22
23
24
28
29
30
16
17
IS
26
27
14*
15*
32*
33*
Additive Stoich
Xi
0
-
+
-
+
-
0
+
+
-
0
0
0
0
-
4.
-
-
-
0
+
+
-
-
f
+
-
-
Gas Tcnp
X2
+
+
-
4-
-
+
-
-
.
+
-
-
f
-
+
+
+
+
-
f
-
-
+
+
-
+
-
+
-
Particle Size
X3
0
-
-
-
-
-
-
0
+
t
i
0
0
0
0
-
-
-
-
-
0
-
-
-
-
+
»
+
+
'; S in Coal
*A
+
+
+
-
+
+
+
_
.
_
-
<0. 8 ^
<0.8
<0.8
<0.8
<0.8
^0.8
+
+
+
-
-
-
-
-
+
- "
+
+ '
Date
Performed
7/9/71
7/10
7/12
7/13
7/14
7/15
7/19
7/20
7/21
7/22
7/23
7/24
7/26
KEY;
LEVEL
t
-
Xl
2.0-4.0
0.5-2.0
X2
289-51S°F
25S-256°F
*3
COURSE (SO'.-'IOOM)
FINE (S05o-400M)
*<
2.30-4.10
1.00-2.29
* Mechanical Collector Inlet famplc
NOTE: All tests were run r'l "B" side. Jlowevcr, first five
tests hnU ploctrj ca'; equipment encrgi:in£ lioth "A"
and "B" sides. lesi1 six on h.id onl\ "B" side
onerci=cd. one set pir section (ftillw.ive).
-------
-38-
V. TEST RESULTS AND SAMPLE ANALYSES
1. Test Data
Tables III through XV summarize the data from both
the CES test programs, and the TVA test programs.
All runs were made on Boiler No. 10 at Shawnee
Station. However, the TVA tests were conducted on
the "A" precipitator while the first CES test pro-
gram was on both "A" and "B" precipitators and the
second was on the "B" only. (See Figure 15).
Since the flue gas and particulate to both "A" and
"B" precipitators came from the same boiler, there
is no obvious reason to expect any significant
difference in results due to the side tested, and
for analysis purposes the test data can be con-
sidered comparable? The only exception is the
optical sensor data which was recorded on the "B"
side and a quantitative analysis requires test
data from the "B" side. However, a qualitative
evaluation of the data can include "A" side tests
as well.
2. Coal Analyses
Tables XVI through XVIII summarize coal sample an-
alyses for both the CES and TVA programs, and the
Babcock and Wilcox pilot plant work at Alliance, Ohio,
-------
-39-
3. Particle Size Analyses (Bahco, sieve and specific
gravity)
Tables XIX through XXII summarize the Bahco and sieve
analyses of samples obtained during the CES test pro-
grams. Included are limestone feed samples, fly ash
samples and reacted limestone fly ash mixtures.
4. Resistivities
Tables XXIII through XXV summarize all laboratory
and in-situ resistivity measurements made on samples
from the CES programs. Table XXVI shows resistivi-
ties obtained on fly ash from various coals used in
the Babcock and Wilcox pilot program.
5. Chemical Analyses
Tables XXVII through XXIX summarize all the chemical
analyses obtained on the particulate samples from
both of the CES test programs. These analyses were
performed by TVA personnel at their Chattanooga,
Tennessee laboratory.
-------
-40-
TABLE III
SUMMARY OF THE TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S FIRST TEST SERIES
(December, 1969)
Test
No.
1A
IB
2A
3A
3B
4A
4B
5A
53
Peed Rate
Tons/Hr.
Coal
57.0
57.0
55.0
58.0
59.0
58.0
59.0
57.0 '
57. a
Lircstonc
0
0
0
0
0
0
0
0
0
Ear.
Press.
"Hq
29.61
29.75
29.71
29.75
29.91
29.88
29.75
29.98
29.96
Duct
Press.
ID Tan
in "H20
-13.90
-13.25
-13.60
-13.30
-12.75
-13.10
-12.75
-12.30
-12.75
I.n-Situ
Resistivity
Pptr. Inlet
Tenp.
o ^»~
-
293
318
293
312
302
OHM-CM
___
4.8xI09
2.1X1010
2.6X1011
4.7X1010
.3.0X1011
Elcc. PTJtr.
Inlet T
Op
-
-
293
318
293
312
302
Gas Vol .
MACFM
275
255
275
273
237
270
230
276
230
Vol.
F?S
6.2
5.7
6.2
6.1
5.3
6.1
5.2
0.2
5.2
(a)
Test
y.o.
1A
IB
2A
3A
3B
4A
45
&
51J
Unit
Load
140
140
137-14-1
110
140
141
1-:]
140
140
Steam
M Lbs.
Per !!r.
S/&
965
940-1000
SCO
960
962
S55
970
9CO
Air
Per Hr.
1030
1020
1000-1C30
1020
1010
1020
102C
1020
1020
Flue Gas %
bv Voluirc
Oi
J.O-b.O
2.3-4.0
3.0-5.0
2.0-4.0
2.0-4.0
2.0-4.0
2.0-4.0
3.2-5.0
3.2-3.9
H-JO
8.3
9.1
7.7
KC Inlet
iCTfp ,
00
295
300
297
30C
303
300
210
22C
200
*P "H?0
A'-:
2.3
2.3
2.3
2.2
2.3
2 . 3
2.2
2.2
2.2'
XC
4.40
3. SO
4.20
', . 30
3. SO
'..00
3. EG
4. 3D
3.75
?otr.
0.3
0.3
0.3
0.3
0.3
0.3
C.3
0.3 ;
0.3
(b)
-------
-41-
TABLH IV
SUMMARY OF'TEST DATA FROM THE COTTRtiLL
ENVIRONMENTAL SYSTEM'S FIRST TEST SCRIES
(December, 1969)
Test
No.
1A
13
2A
3A
35
47*
4E
5A
53
T-R Set B2 - Outlet Section
.Sp^LS
Nin.
.
78
143
145
130
volts
*c
300
233
229
300
7-.r.ps
;.c
73
50
50
SO
KVolts
DC
33.8
25.2
25.3
23. S
Aro-;
DC
.26
.1-i
.13
.32
T-R Set A2 - Outlet Section
Mil".
0
3
100
jr-
200
15
Volts
f-C
305
310
200
- - ~~~
250
330
^
Air.ns
A<-
70
79
SO
"**-
50
50
-
K volts
DC
34.4
34.9
22.5
-
28.2
37.2
f.ips
DC
0.30
.32
.26
*
.24
.24
(a)
Tast
No.
1A
13
2 A.
3A
3b
4A
4B
3A
5B
r-F. Set Bl - Inlet Section
Spfcs
Mm.
1-50
143
85
150
160
250
3=0
70
C5
Volts
AC
330
345
355
250
233
250
228
350
305
Amps
rc
60
63
75
40
35
30
34
60
73
KVol ts
DC
37.2
38.8
40.0
28.2
26.2
28.2
25.6
39.4
34.4
;>.:nos
DC
.28
.30
.34
.12
.105
.12
.10
.40
;,33
p
T-R Set Al - Center Section
Snks
.':J.n.
150
145
95
150
15B
150
158
118
140
Volts
AC
315
330
350
278
283
265
268
330
305
trips
*C
60
73
88
50
C5
50
57
90
EO
KVolts
DC
35.5
37.2
39.4
31.2
31.8
29.8
30.2
37.2
34.4
A^-.os
nc
.33
.40
.50
.24
.35
.24
.23
.46
.44
(b
-------
TABLE V
SUMMARY OF TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S FIRST TEST SERIES
.(December, 1969)
Test
No.
LA
13
2A
3A
33
4A
4B
5A
'53
Power
WrtttS
1000 ACFM
73
89
102
38
40
42
34
91
113
Wntts
1000 Ft*
720
740
940
360
3GO
410
300
850
1000
Grain Loading @ 70 °F
& 30 "Hg-Gr/Ft3
KG
Inlet
3.17
3.09
3.22
3.14
2.73
3.31
3.20
2.95
MC Outlet
Pptr. Inlet
1.45
1.37
1.19
1.20
1.42
1.26
Pptr.
Outlet
.036
0.227
0.328
0.112
0.045
Removal
Efficiency
%
KG
55.0
56.4
56.5
63.8
55.7
57.3
ESP
83.5
72.8
92.8
96.4
Overall
98.7
92.6
91.5
96.5
98.3
M4 rtT-af- < «*
Vel. W
FFS/CMPS
.190/5.8
.13/5.5
.41/12.5
.43/13.1
-------
TABLE VI
SUMMARY OF TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES
(July, 1971)
Teat
1
:
*
/.
5
fc
:
0
JO
I'nlt
l-"y
1"*
'?7
'JT
1 10
1.! 1
K.Z
i:»
i : .
L"*
'A ., "ILI
1 ^
56
I"
Jf
!&
Zc
2)
22
2]
i t 1
l ' >
139
1 1-
m
140
I4T
i-=i
i "
a* ,,.
7?
' T"
Stcr.-n
V. l.bs
Per <:r
n-i-
t, no
ft »*%
i .T r. o
1 for,
: n -n
ir. "
1010
:ni"
li'l n
>»o
l.T"
9'.o
"SP
1CTU
H'J
001
n.-in
"Ifl
9!'0
PSO
".-.T
1* ,,! | ,-M
? ? [ i T o
£i
«:<»
JC
ji
i-s:
i '.i
MS
r,f
'* -.if.
o«n
M"0
.,,pn
].":'0
Air
M Lbs
Per
!!our
in.
1070
n-n
1 1 :r
1 1 O f,
;:.i(
' :m>
l,.nr.
' ;no
IO--0
Lli/0
Flue
CAS
- ly
Vol .
' .0
'. .-1
2 . o
_
'..2
I./
4.5
3.1
2.7
4.3
"!70 1 -t.t
10-10
M'.i
10C5
IJ'iO
'. >»?
Ill »
i n -j o
inpo
ipoft
1 nro
'"70
1RSO
in,--;
,.,
inr-.:
fGfl 71T
4.7
1.1
4.0
C.7
5.0
S.3
r, ^
^
5 P
t )
/ r.
f ?
^ 7
:.P.
., ,
Til ! IP'ii) | '..0
?luc
Cr. s
»/by
Vol.
R.O
r,.p
1! .3
r,.7
9.0
7.0
6.3
8.0
7.7
6.3
7.3
5.8
S.fi
4 .3
5.1
5.4
4.9
/! 7
,. s
ri t.
C..2
K ^1
r. .r,
4.7
I."!
6.1
6.9
6.3
KG
Inlet T.
P.
114
314 .
?70
77
2« 5
1'2
77f.
?G5
770
111
310
763
?60
?rt
310
757
310
7F.O
11 n
11 f.
71 R
273
31 0
2f!l
11 1
?r,n
319
310
7^,0
£
AH
2.S
7.7
1.2
2.".
7.9
T> "I!
KC
1 ^C
1.5
T.»
1 7
1.8
7 . f> il . 5
7.5
2.r,
2."
2.5
2.5
7.'.
2.6
2.S
2.8
2.5
7. .r,
?.r,
L_2.5
7.5
2.G
2.5
2.7
7.1
3.3
1.'.
1.5
1. 7
1.1
1.7
1.5
1.3
l.r,
1 .4
3.5
3.5
3.5
3.4
3.6
3.4
? -
3.1
7.7 |3.7
f .6
2. 1
3.5
3.2
"
Pptr
0.5
0.1
0.4
o.s
o.s
0.5
0.5
P. 5
0.5
1.4
0.5
n.f
0.5
0.5
0 5
0.5
0.5
o.r,
0.5
P. 5
P. 5
0.5
0.5
n i
0.5
n.s
0.5
i 1
food Rnte
i'cni/1'r.
Co.-i | ].in . ;
r)q>r,
17.7
5R.°
R7.0
fi?.2
«;i .?
C2.1
C1.fi
f.'. . 3
f.7.5
5;. 3
Cl.Q
c *
r,?.i
c:.o
'. r. . 7
5«.4
n
7 .;;
R.^O
4.7S
; i . r. o
11. IS
15. 7S
15.71
14 . 1 ft
J 4 . 1 S
0
0.70
?.lr.
0
0
P
0
1.80
3.45
10.55
7.05
6.45
11. JS
r, .75
j.30
n.so
7.ns
I3ar. Prcr.r,
79.87
79.70
?°.PS
79. fll
71.B3
2y. /(-
79.7-)
79. C-o
?9.fi7
20.7?
20.71
70.89
79.00
29. 8C
29.84
."".Rl
7".P7
79.05
29. R2
29.32
29.68
29.7(1
79.75
29.90
79.90
23.33
21'. 70
29.70
Duct Press.
ID Pan In.
"11,0
-13.5
-13.7
-1".3
-14.8
- 1 3 . 9
-13.5
-17.1
-11.5
-12.0
-17.5
-12.6
-11 .7
-11.0
-1 1 .1
-12.0
-17.0
-12.1)
-17.0
-17.1
-17.2
-12.1
-11 .8
-17.1
-11 .7
-12.1
-11 .1
-12.1
-10.0
-11 .2
Elce. Prcelnitatcr
Inlet T.
F.
293
314
1 251
305
?46
301
25G
246
251
290
289
744
241
713
2C9
23B
7B1
241
289
292
296
253
269
242
290
241
298
289
241
Gas \ol
509
2«4
-"7
?5K
3 12
>74
26i
Jfi?
2'4
2q,
256
JSP
f.t
1*7
?10
>P«
7fi4
262
234
r»i'
K -I
f *
S .7
a ^
s ^
f 0
fi.J
5 q _j
S 4
r 4
r A
S 7
S g
,t ,
K 1
^ a
ft c
1 Q
6.3
6.4
284 6.4
268
296
265
292
2'. 'i
:'jj
?eo
259
6.0
6.4
6.0
6.6
S .8
E.C
6.5
S.3 _
-------
TABLE VII
SUMMARY OF TEST DATA FROM THE COTTRELL
ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES
(July, 1971)
1 -r-* *--. r
.7r:;K:;'
VM'.I
AT
Li '> h«
t 1 1* | !""
3 In:
"V l~.-3~"
T~nT
)
C >!
: i !>!
" i';
j j 01
t '. . :
^ i : : i
: ;n
1 .?_.
I'S
:;* ~
23:
_!Ji_
!"1
73"
~:7i~
l-1-.l-t S-cf.r-.
*;?*
i.19-
15
. j
5
! J
:c
r. volt^
:».»
:>.=
J3.S
'*-.'
;? i
21.2
~:1 -7-
7; :».2
1 37
**
1 »
27
25 J
.-. ir-Ji:- J '2
> \. -15 )'. 4 I !
' 1 "
'. 1 5 "
Li'.Li'
L ! 1 "''
r-'.'-U'J-
l_».-_J-'/'_
_J'._U2-_
?7 »'
t£~> i»~
L " ! ''
r!i_L»
r:i
:.:
SI
.-«
?'.'. j <3
Jrl
1 !
71 i
?' *
'-£
~4
1 ;
72
27
77
-Ii'J_±L_
7! 1
2? n
26.4
? '. . 3
T«'
'"!"ss?"
.".i
.n7c
.ma
j.1-5
.'jn
.ifil
s . i o
o rp.
17.1 1 0 «
^1
10. < \0.?",'
21 S
:: ;
2! <
:jj±-
»' %
7S.7
7S 2
70.3
Lk-i.]
s . 2 -.
b_*-.
!i^
o : i
£.1"
T-n
fEi^
'Set M Cinter G«etlon
Voltoj A.-ipa
C 1 NT
_rs fl?7*
73 J112
70 172
73
70
53
OS
7J
75
ro
70
79
75
7'-
75
S3
55
53
07
f.»
: 77
IDS
:74
:ii
221
216
174
174
274
71 f
1' 9
272
:;
J!l
43
10
'10
-s
«s
<5
23
17
30
5
S
25
«S
X Volte
DC
33. C
21.75
21.6
21.2
7y»P*
DC
O.JO-
o.on.
O.C5"
o.occ
22.5 O.OC
23.8 | O.OC"
2?.C | .11*
20. «
:s.i
2C.S
;i>.o
12.7
25.0
<5 i 2-1.3
-*
OS
<9
14
1 1l\ 5
-TTflTo-
7 5
u_»
_^.-k -;
> . 9 > J V 7
o.: :
0 IV
_L'l
15S
C? 1 7M
i
37
5
10
12
<5
10
RC 1 253 j Jl
21.1
17.3
32.4
2?. I
25.2
?0.1
!».<
2«.3
20.7
77.7J
24 0
.0"S
.cso
.0',3
.or.o
.0?tl
.07'.
.C',0
.043
0 '2"
0.70-
0.2;r
0.11
0.0?
o.c?
0 0'.
C 0"
0.11
9.C'.
71. Si 0.1P
?0.2j 0.17
T-R
SpXs/
HlB.
J5
100
100
10S
100
no
100
100
no
107
29
0
22
:D
30
0
27
;s
30
0
30
30
9
s
Sot H2 Outlei Section
Vclta
174
337
180
151
'95
167
242
?es
2C3
?.7
293
217
234
225
1D3
20G
7(4
263
139
705
115
14:
215
_>.-.!_
19!
251
.-'.!
AC
10
10
<0
«5
«5
c5
00
73
41
i:
«5
21
25
?4
JO
77
80
f.5
01
'.3
K.
S
<3
7,
51
67
H VoltalAnp*
"; 1 rw
20.9
22.35
21.5
18.4
71.5
20.0
2.,.9
3<.l
31.4
75. S
?4.3
2C.3
?3 0
:e.i
23.7
31. S
32.9
7C f
2<.S
23.5
i9.3
J3.3
21.7
23.7
00 ?
31.4
.O'.C
.040
.OiO
.01-:
.020
.nil
.??>
. 3)0
la*;
.Ot!l
.0(1
.100
.103
.ICO
.otn
.353
.211
o.:c
o :.-
G.I 0
0.30
O.Cl
0.1?
C.ll
O.?l
o.m
I Grain LoA
3?<
7C8 .
1 MC
tnloc
l.o
P.inol
5.46
5.10
3.23
3.22
6.37
7.23
".
e '15
6.J7
__
^^
_«.
9.23
0.13
MC Outlet
Pftr. tnlp
Fl-nple
1,'JS
2.27
r.ri
3 .74
2.36
).)«
1.23
2.19
3.73
?.9J
3.75
1.43
2.30
2. 315
4.42
2.49
2.3)
2.82
7.07
3.S9
7.29
3.27
3.22
3.4?
4.61
3.42
Pptr.
9.3)
0.44
1 .57
1 .63
1.71
1 95
0.35
0.12
0.12
0.75
0.93
0 5?i
f.390
0 214
O.SO
0.19
0.12
0.13
0.79
1.73
1.17
0.11
0.74
0 4?
0.5*
0.51
1.15
0 71
0.18
II
tff
64.3
56.7
31 .6
4« 1
.«!_«
D.R
51 9
Jr. ?
m^^
.
~
|
S
cnov«l
lcl*nffw, t
77 .4
30 8
24.7
30. S
\2i»
«9 2
"S .5
SO }
76 3
86 .7
72.6
9? '
64.1
91.9
91. «
S» 1
54 .7
(a o
"i.4
It, 7
B.'.t
P» 1
67 0
9« . g
94..,'
91 9
69 7
49 C
*! *
95 7
,.«,.
97 B
"
. _.
_
""
97 i
97.3
VrT"« CB
C 21/7 )
0 t&/l f
0 PS/1 6
0 41/13 !
0 76 '7 9
0 1 9 'S T
0 It 5/5 0
0. 4 3
0 17/S.J
O.Jl/J 0
0.2V.S
o.2» ..:
0.41/11.0
-------
TABLE VIII
SUMMARY- OF TEST DATA FROM TVA' S FIRST TEST SERIES
(July-August, 1969)
Test
r*o
^
5
/
15
24
25
27
23
30
3i
23
24
16
3J
3D
1 .
f ^
"I ..
Gas
Flow
.". ACFJ!
258
252
203
227
282
302
230
. 2.11
2.5
2:1
235
237
235
327
324
340
373
Unit
Load
KW
140
142
134
130
144
143
125
124
139
141
137
137
133
137
136
137
136
Pptr.
Eff .
%
95.8
95.6
97.2
98.0
94.9
94.4
96.7
97.6
97.8
S8.4
96.6
95.7
53.7
95.8
94.0
^94.9
[ 95.0
Pptr.
Gas
Tenp.°F
303
303
308
312
304
304
271
271
263
268
272
272
| 323
317
f- 317
308
308
Lime-
stone
Rate
Tons/Hr
0
0
0
0
0
0
0.
0
0
0
0
0
0
0
0
! o
[ 0
TO A T"P C
VI A lib
103 ACFM
S4.3
98.9
132.2
108.8
101.4
92.9
102.0
130.1
210.9
202.4
| 108.3
{ 100.1
87.9
13G.O
104.4
i 108.9
i £3.2
W A lib
103 FT2
818
839
8SO
831
963
945
858
1056
1534
1506
930
866
873
1438
1139
I 1247
j 1108
MIGRATIOI
W
FT/SEC.
0.46
0.44
0.40
0.50
0.47
0.49
0.4S
0.50
0.4G
0.51
0.48
0.45
0.46
0.53
0.51
0.57
0.63
J VELOCITY
v;
CM/SEC.
13.9
13.4
12.2
15.2
14.3
14.9
14.6
15.4
14.1
15.6
14.7
13.8
13.9
17.7
15.6
17.3
19.1
GrAirJ LOADING
Q32cr-23.S2' rr
OvJi'Lll
grs./f c^
0.0712
0.0697 j
0.0-^91
O.C30S
0.0352
0.123-;
0.0^3:
O.C;o:'
O.C2CC
0.0215
O.C455
o.cs:3 i
:
0.0752
O.C3CC I
0 . C 2 ", 9
O.CS17
O.C73
-------
TABLE IX
SUMMARY OF TEST DATA FROM TVA'S FIRST TEST SERIES
(July-August, 1969)
Test
; >;/; f
It
5
7
io
24
I' 5
Z7
23
:o
. i
'. 2
2-;
;a
:s
29
t -
^2
T-R SET
Spks
Mm
154
195
214
329
27
40
140
291
70
132
167
177
I 69
15
16
23
92
PRI
Volts
AC
335
342
335
345
360
363
329
284
342
320
324
348
333
350
351
336
322
1A (FULL WAVE)
PRI
Amps
AC
84
86
97
90
89
93
90
87
102
93
3D
38
93
111
112
112
106
SEC,
Amos
DC
0.22
0.22
0.25
0.22
0.245
0.26
0.235
0.22
0.29
0.29
0.24
0.235
KV
Avg.
40.
40.8
40.0
41.2 i
43.0 ;
43.4
39.3
33.9
40.9
33.2
33.7
41.6
0.255 I 39.8
0.325 I 41.8
0.33 41.9
0.325 -10.2
0.29
38.5
T-R SET
Soks
.''in
129
150
193
105
U
14
121
139
63
100
130
132
-17
15
16
23
S2 .
PHI"
Volts
f-C
J41
360
327
355
372
377
3
-------
BLE X
SUMMARY OF TEST DATA FROM TVA'A SECOND TEST SERIES
(June-July, 1970)
Test
?:c.
4
^
3
10
LLj
u
i S
"7
' 3
_\2
> 1
73
T ;
??
?
TO
3 1
3 ;.
?Tf~~
'C-
"ft
Gas
Flow-
M ACVM
286
'55
24 1
23^
?39
!>7]
266
269
277
278
?30
?R3
Unit
Load-
MW
1/iQ
i-;o
1 a-}.
127
330
.Jr^n
ill
_J £. J
140
143
145
141
501 1 1 -1 1
o o - j i j i
-,00 n."l2
30?
?7ll
377
77C1
2<53
2C9
?F.fJ
?.1. i
6.3
fi.3
5.7
f .0
C.2
6.7
t; i
5.4
6.8
5.1
5.5
5.2
5.4
Lime-
stone
Rate
^Tons/Sir.
0
1] .0
9.5
0
9.0
0
5.0
9.D
0
5.0
10.0
0
0
10
0
5.5
9.5
0
5.15
10.0
5.0
10.0
0
5.5
1 0.0
0
0
4.5
Coal
Rate
Tonp/Kr^.
62.5
62'. 5
64
56.5 1
58
62.5 i
63 !
63
62.5 I
66.5 i
6S i
r>3
66.5
r,3
C=3 !
64
61
59.5 !
59.5 '
59.5 !
62.5 i
63
62.5
6 C . 5 I
C2 i
6£
64
66.5
-------
^E XI
SUMMARY OF TEST DATA FROM TVA'S SECOND TEST SERIES
(June-July, 1970)
IGSt
\'o.
4
*
=3
L2_
ll
ii
-i
7
Jfl
19
21
?3
i .
?£
?.7
?3
70
"*!
"?
7 l
> r
"J '
"S
' -i
:o
-.2
-3
W ATTC
103 ACFM
35.9
27.3
44.1
35.7
JD.10
27.4
in. 7
d.3
15.6
9.7
7.0
14.7
48.8
32.2
8H.6
23.1
2 3. J
i'l'j.a
31.4
20. &
69.8
^ L .10
50.5
53.2
47.8
53. !>
67 . j
40.7
WATTO
103 FT2
346
262
367
281
01
250
96
75
14G
91
66
140
4G
0.30
0.23
0.32
0.3-1
0.26
C.27
0.41
0.30
VELOCITY
'j
/
cm/sec
10.9
6.4
7.5
8.1
4.3
8.5
5.6
5.6
7.9
4.5
3.0
6.3
10.0
5.9
12.
-------
n
xii
SUMMARY OF TEST DATA FROM TVA'S SECOND TEST SERIES
(June-July, 1970)
Test
No.
4
s
c
1 n.
11
13
;
1 ' ->
7
\ ?
.19
1 1
?3
?-'-
?;;
7 7
- °
- >
:'n
1 --
I ''
~ G
I .'«
i
i f:
-I
T-R SET 1A (PULL WAVE)
SPKS
Win.
0
C
0
18'J
2] 0
ino
395
IftO
?1 5
215
215
20'j
140
1 ', '
:r.o
305
lf.p.
30
If. 5
PRI
Volts
AC
235
275
?50
250
">CO
2i')0
1'JC
] f-2
?30
205
200
2'iO
255
PRI
Amps
PS
70
Sec.
Amps
nr
0 ]5
0.15 -i
315 ' 0.0 ',
35 0.05
KV
i«. n
32.8
? '- . 3
20.6
0 0.03 2"» . 9
30 s 0.0-55
10 i 0 . i ) !
0
15
10
in
2f)
40
0 . 0 L 5
o . o ;
L3l.O
: / . 7
T-^ S"T 2A (FULL WAVE)
SPKS1
"in.
120
3
y 4 c l
- o .
17;-
f 1-^ =
1 - v^
..i.?-? !| -r-
O.fM j 2; .4 || 10.
0.03 123.5;
0.0 {5 1 2'. .2
0.035
2? 5 Vi f!.0.~>
330
73 (i . : '-.
225 "? T 0 . 0 <"<
2.'0
3 '1 5
>35
1 r, . | ? 1 0
5 ° 0 1 7. 7 0
' <; 0 i 2 -, 0
20
0.0 '»
j n _ ;
LiC^
r i «. . i
? ' . °.
L ?r, .->
1 > 5 0.3 | '. 1 2KO r.r, i o.i-
410
-I \> -3
430
150
160
( , ? . 2
j_ . , . ".
1 ? ! . .
270 1 '>'' 0.1 .5 !
2C5
200
.r "i 0.115
(>.0
C . 1 ' 5
310 80 0.1'S
270 60
0.11
j V..'.
? '. . C,
!i 7 . ';
32.2
1 -'-
i -c.-
I "-
, -- .
. .
1
- / .
. '
.
. .
-
_ .
] ~ '
?n
Volts
AC
2:50
PRI
AC
30
2J5 22
szc.
.^10 s
nc
0.08
KV
Avg.
29.8
0. 05 26 . a
j i J 43 i 0.103: i S . 8
2_>5
l-iV
45 | O.ui) | 30.4
20 i 0.05 /:t>.2
2n5 ' 33 O.IJ5
2 j'j
220
2 + Q
^60
-i^
-S-o-
10
10
3 ij
~~ _ t | . j
j^i. , (33
2 iO
^ ^ -^
.. J3
.' i:j
:";3~
iJ . 0 3
C . 02
0. ua
O.uG
0. 05
~O.C3'J~
J'l .0
Jfa . J
I-3-!.'-!-
2G.2
2"5.0
Jl .0
0.&73 2y.8
J.3o
""07! 75"
2v. . 2
JiTtf
20 ' 0 . 0 tj ' J f> . 2.
2 J
7 i
~T2^
j ^ 'J
0 . Jt
J72T
26. 2
0 . ] o :i 2 y . 8
C.u~j" 27. 4"
T-R SET 3A (FULL WAVE)
SPKS
.'lin.
155
160
500
180
2 'JO
Ib5
1'JS
r ji3
li'O
183
iyo
105
ibO
ri1? l
uo
4!?=
loC.
^76 O.::0 , 3j.s 1 bOO
-0,. | 33
.. 7 j i J ^
. -3
i 7T!
uL»
! o/
0.1-,
3o..O
U.i^5" 32. li
U . 2 U"~ p3 -1 . 0
o. 2
' .< ^3
03 C.iw3
33 . 2
03 . fa
45 | 0.125 21.6
buO
500
500
300
PRI
volts
AC
233
11JG
PRI
Anps
AC
50
125
250 'j 00
200
I100
i7"0
1:10
205
ll)3
163
13b
L'/O
330
~JJ523
-T7CT-
Tiij "
liTj
^20
l_2 ;o
^vr
300 i i'10
1 j j J^ 0
210
15
0
16
sec.
Air.ps
DC
0.10
O.OG
G.2'0
0. 10
C.02
KV
AVfT.
27. S
22.7
2 'j .
2J.9
u.:
C . o 1 ' ?0 . j
1.2 C . O'1 2 1 . ->
2 3 i C, . <; \>
2', . ,
U 0. 0^ l 1 y. /
0
0
15
L,0
0. 02
0
0. Cj
ly.7
1.-..1
^ u . J
0". L>J"T 3'J". ".
; j i) . _ ;
I GJ
2^
JO
C j
3"?
i;
| ^ti . 0
PJ y . ;
j *" '
37 | O.i/ | ^~ . 'j
V, J
. 1. 1 i j - . j
2oO | -'.0 | 0.1&
^_. 0
vo
I
-------
XIII.
SUMMARY OF TEST DATA FROM TVA'S SECOND TEST SERIES
(June-July, 1970)
Test
No.i_
44
46
47
18
50
51
52
54
55
56
58
59
60
61
62
64
65
6t>
68
69
70
72
73
74
Gas
Flow
M ACFM
299
2yi
283
280
239
237
239
285
285
280
279
279
283
302
296
294
293
290
287
275
273
227
222
223
Unit
Load
MW
144
142
139
140
142
142
143
140
141
141
142
142
144
141
143
142
142
142
140
140
142
139
140
143
Pptr.
Eff .
%
85.3
92.6
77.3
83.4
93.7
91.1
89.6
89.8
71.3
79.3
94.9
88.3
82.0
91.6
81.3
93.4
82.6
74 .0
85.6
78.6
78.8
88.5
68.0
87.2
Pptr.
Gas
Temp.
OF
316
JOb
306
306
307
313
320
310
. 310
310
304
304
304
304
304
310
310
310
309
309
309
311
311
311
Ultimate Coal
Analysis (Dry)
Ash
%
15.9
17.1
15.8
15.7
14.0
14.0
14.3
13.7
13.6
13.7
14.0
13.2
12.9
13.8
14.0
14.2
13.6
.13.6
14.8
16.3
15.8
20.2
14.0
16.2
Sulphur
%
2.7
2.7
2.7
3.0
2.7
2.8
3.C
2.7
2.8
2.8
2.8
2.7
2.5
2.6
2.6
3.1
2.8
2.6
2.5
2.4
2.4
2.5
2.4
2.4
Ash
Sulphur
Ratio
5.9
6. J
5.9
5.2
5.2
5.0
4.9
5.1
4.9
4.9
5.0
4.9
5.2
5.3
5.4
4.6
4.9
5.2
5.9
6.8
6.6
6.1
5.8
6.8
Lime-
stone
Rate
Tons/Hr.
9-5
U
5.0
10.0
0
5.0
10.0
0
3.3
2.25
0
2.3
1.25
0
1.2
0
5:0
10.5
0
1.4
5.5
0
1.3
5.5
Coal
Rate
Tons/Hr.
68
64
62
62.5
64
64
to. 5
62.5
63
63
64
64
68
63
66.5
64
64
64
62.5
62.5
64
62
62.5
66.5
I
(Jl
o
I
-------
TABLE XIV
SUMMARY OF TEST DATA FROM TVA'S SECOND TEST SERIES
(June-July, 1970)
NO. 2
-^*__
=~~"~
J-J
T t
i.Q
'.-1
( J
t b
^ j
- 0
C £
>3
"/;
WATTS
103 ACFM
21.7
6277
19.7
18.1 I
72.3
33.8
29. S
57.1
21. 6
20.5
63.2
27.1
22.1
59.6
3 ', . G
94.1
30.7
22.1
A 1.4 "
24.3
21. 7
G1.5
3-J . 4
3~2T^
WATT^
103 FT2
219
623
187
171
582
2G9
237
548
207
193
593
2b5
211
606
345
931
302
216
400
225
199
470
257
243
MIGRATION
W
ft/sec
0.32
U.4J
" U:2^'
0.23
0.31?
' O.J2
0.30
0.36
0.20
0.24
0.45
0.3J
0.2;
0.42
0.27
" 0.44
0.28"
" 0.21 "
O.Ji
0.23
0.2J
0.27
0.26
U.^b
VELOCITY
W
cm/ sec
9.8
13.1
' V.2
y.b
11.3
9.8
9.2
11.1
b.l
7.5
14.2
10.2
S.3
12.8
a. 3
13.6
ft.tt
6. &
9.5
7.2
"7.2
' '8.4
e.o
V.B
flFlAIN LOADING
@ 32°F and 29.92"Kg
OUTLET
grs/ft3
0.319
0.1J22
0.311
(J.329
O.OiiiiO
O.Ki
U.22JJ
O.l4a
O.i62
0.3J4
O.OJ/0
0.246
0.27&
0. Oi;65
0.24JI
0. Oy-Jl
0".3oJ
o.4ia
0.21-1
0.319
0.3b2
3.129
0.162
0.214
I
U1
-------
TABLE XV
SUMMARY OF TEST DATA FROM TVA'S SECOND TEST SERIES
CJune-July, 1970)
Test
XC.T
A4
~ K>'
47
+£>
b'o
~ 53
' 52"
~ it
!>S
Se
5S
50
id
L'Vi
T fc-2
t«-
't>5
tfc
03
1-9"
: '1C
*~ 72
t?J
[74
T-R SET 1A (FULL WAVE)
SPKS
170
155
1G5
170
160
]65
16S
160
Io5
165
1GO
165
165
155
1GO
150
165
158
160
165
165
160
162
165
PR I
Volts
AC
235
2'J5
230
225
320
210
230
255
240
235
290
200
235
310
290
315
240
230
285
250
250
310
255
240
PRI
Amps
AC
35
55
30
30
60
35
31
40
30
30
47
30
30
70
50
70
37
30
50
37
35
60
35
37
SEC
Amps
DC
0.07
0.145
0.065
0.065
0.14
0.08
KV
Avq.
28.083
35.25J
27.485
26.888
38.240
2 G . f .' 0
0.07 27.433
0.035 30. 4 M
0.07 1 28.0 (30
0.065 j 2S.083
0.105
0.075
0.07
0.15
0.10
C.175
0.08
0.07
0.105
0.08
0.07
34.053
31.070
28.0H3
37 . (.43
34.fi35
37.643
28. o:'.0
27..'.'j5
34.038
, 2 9 . 8 / 1>
2 9 . 0 / .>
0.13 37.0-.3
0.075 30.4/.J
0.065
28.630
T-R S2T 2A (FULL WAVE)
SPKS
Min.
170
PRI
Volts
AC
240
160 290
180
230
135 i 225
165 i 230
180 243
180
235
165 290
180
IdO
230
230
170 250
180
IdO
240
235
1-10 , 330
Ib5
145
170
"Do
160
255
300
240
235
275
170 " 240
170 240
PRI
Amps
AC
30
57
30
27
56
33
30
60
30
30
47
28
30
60
45
61
35
31
SEC.
Amps
DC
0.06
0.155
0.07
0.065
0.135
0.085
0.08
0.14
0.03
O.OS
0.11
0.08
0.075
0.17
KV
Avg.
28.680
3/1 .655
27.485
26.888
33.460
29.278
28.083
34.655
27 .485
27.485
31.070
28.680
28.083
35.350
0.115 31.6G8
|_ 0.175
0. 085
0.08
50 | 0.13
32
0.09
30 o.oes
35.350
23.680
28.083
32.863
28.630
23.630
Ia5 270 | 50 i 0.12 32.265
175 i 245
175
245
32
32
0.08
0.08
29.278
29.278
T-R SET 3A (FULL WAVE)
SPKS
Min
270
160
170
170
160
165
165
160
Ifa5
168
PRI
Volts
AC
215
280
195
190
L270
225
220
285
205
205
155 1 295
163
165
225
205
160 280
1S5 220
120 335
1KO 210
182 210
175 260
180 205
180 : 195
175 2CO
ISO | 230
180
230
PRI
Amps
AC
25
45
25
25
50
29
24
1'j
20
20
60
20
20
40
27
67
23
19
29
20
20
37
25
27
SEC.
Amps
DC
0.110
0.24
0.03
0.07
0.23
0.12
0.11
0.26
0.08
0.07
0.30
0.11
f .09
G.19
0.12
0.37
0.17
0.09
0.13
KV
Avq .
25.6
33.4
23.3
22.7
32.2
^a .8
2 fr.2
34.0
2 ! . 4
24 .4
35.2
26.8
24.4
33. '.
2fj. A
40.0
2J.O
2b.O
30.0
0.07 ! 2-', .4
0.06
2J.3
0. ib 3_ . 0
0.11
O.li
27.4
' 27.4
cn
M
i
-------
-53-
TABLE XVI
COAL ANALYSES FOR BOTH CQTTRF.LL
ENVIRONMENTAL SYSTEM'S TEST SERIES
(December, 1969 5 July, 1971)
Run(i;
No.
1A61B
2A
3A
3U
4A
4U
SAG SB
1
2
3
4
5
6
8
9
10
1J
14
IS
JG
17
IS
19
20
21
22
23
24
25
26
27
2S
29
30
*/.
33
Moi sturc
10.10
5. 30
9.90^
10.40
9.40
S..SO
S.OO
10.30
11 .00
9. JO
10.<>U
10. SO
S./O
JO. 'JO
10. SO
10. SO
11.10
9.20
!0.10
8.50
8. -10
S.60
7.yo
S.20
7.20
6.90
S.9U
8. 90
7.- 10
S.70
s.:o
7 . 20 |
Vol.
Comb.
!!at tcr
33.93
3f>. 1 0
5i Go
j 2 . 5 !>
32.87
51 .99
30. SI
29.1 .>
2 'J . 2 2
50.52
jO. 2b
:s.s2
2S.6G
j J . 9 2
3 1 . ° 2
5 0 . 3 b
34 .SI
1 w . C 0 3 3 . « 0
S . 5 0 j i 5 . 2 i>
10. ?>) 1 3-1 .('
S.60
J ( . 4 7
Fixed
Carbon
-14.52
J S . S D
15. S9
15.86
15.90
4 3.. S3
4 .0 . / 9
45.62
45.06
4-1 .35
: 1 . 2 S
4. ''.64
41.55
12.60
41 .00
40.20
J1.57
41.73
4 -I . 1 6
45.3 !
'! 5 . '. 8
16. SO
4 j .OS
'12.71
'I3.S9
13.63
Jl . 13
J0.09
'M.I A
16. OS
1 J . 5 'J
59 . 70
1 1 70
.: 2.43
S 7 . 4 4
^7.99
Ash
11 .45
12.11
10.75
11.15
9. »7
12.44
9.7S
13.39
14 .02
13.42
IS . 12
1 ... h 0
IS. 01
1-1.11
16. U5
16.39
16. ^1
14.0)
13.15
13.49
1-1.13
13.79
1 S . b 9
1 1) . S 7
1S.S9
19.19
21 . 15
22.15
1 S . 5 0
1 1- . 5 0
1 2 . o 5
1 J . 2 3
1 S . 1 -'
15.79
10.97
J 'J . '.i
Sulfur
Pyritic
1.44
2.24
1 . 25
0. S2
1 .16
0.9-1
1 .67
1 . 59
1.41
1.47
O.Od
1.59
1 .64
1 .48
0.7S
0.77
O.S2
1.55
1 . 2/
0. 72
0. 92
1 .24
0. it
0. J4
0.25
0. 30
0.55
0. j6
1.07
1 . 2S
1 . U4
1 .74
1 . IS
1 .50
2 70
2. IS
Organic
1.32
1 .44
U.SS
1 .06
1 .52
0.92
1 .52
O.SS
1 .01
0.96
0.67
o. y&
0.31
1 .00
0.77
0.79
0.80
1 .US
O.S9
0.70
0.67
O.S4
o .sy
0.57
0.5S
0.65
0.6S
O.SO
0.3/
0.94
O.uS
1 .46
i . v :
Sul fate
0.04
0. 04
0.02
0. 02
0.03
0.03
0.03
Total
2.80
5.72
2.15
1.90
-J.71
i .sy
3.22
0.10 1 2.37
0. 13
2.55
0.12 I 2.55
0.04
0.14
!_O.OS
0.11
0. 07
0. 04
0.06
0. 06
0. 06
0. 03
0. 05
0.05
0. 03
0. 04
0.0?
0. 02
0.04
0. 06
0. On
0.05
0. OJ
0.14
0 ! 0
1.22 I O.OS
1 . 57
2.69
2.65
2.59
1 .62
1 .60
1 .63
2 .69
Ash
Sui ru-
4.2
j . ^
5.0
5. 9
3 . 4
6.6
3.0
5.6
5.5
5 . 3
13. 5
5. 4
6.9
5.4
9 9
10.2
9.8
S. 2
2.22 i S.y
1 . : S
1 . 62
2.15
O.S.I
0. SS
O.S6
0.95
: .o?
1 . L'2
2.00
2.27
1.75
3 . 34
2 . 30
2.66
9. 5
8. 7
6.5
25. 7
25.4
21 .6
20. 2
19.$
IS. 1
9. 5
5.9
7 . 4
5.5-
6 ft
5.S
120 50.10 i . Oo 4.2
1 .57
0.22
J . 04
J . i»
-------
-54-
TABLE XVII
COAL ANALYSES FOR TVA ' S FIRST TEST SERIES
(July-August, 1969)
TVA
TEST
NO.
4
5
7
16
24
25
27
28
30
31
33
34
36
38
39
41
42
MOISTURE
11.9
12.2
13.0
9.2
9.4
9.6
11.4
10.9
9,9
10.3
10.7
10.9
8.8
8.3
8.3
7.9
8.3
VOL.
COMB.
MATTER
34.62
33.80
32.80
35.05
34.34
33.99
31.36
32.34
35.50
34.44
12.24
:i.90
34.11
34.39
34.35
33.89
34.00
FIXED
CARBON
42.99
42.85
42.72
42.77
43.94
44.93
43.50
43.93
44.42
44.67
45.63
45.98
44.41
45.57
44.75
45.04
46.07
ASK
10.48
11.15
11.48
12.98
12.32
11.48
13.73
12.83
10.18
10.58
11.43
11.26
12.68
11.74
12.10
13.17
11.33
TOTAL
SULFUR
2.73
3.16
3.39
2.63
3.08
2.44
2.04
2.41
2.70
2.69
2.14
1.69
3.01
3.39
3.76
3.59
3.02
HEATING
VALUE
ETU/LB .
11,189
10,993
10,823
11,168
11,298
11,327
10,738
10,968
11,533
11,401
11,171
11,191
11,300
11,545
11,527
11,448
11,580
ASH
SULF'JR
3.8
3.5
3.4
4.9
4.0
4.7
6.7
5.3
3.8
3.9
5.3
6.7
4.2
3.5
3.2
3.7
3.8
-------
TABLE XVIII
COAL
ANALYSES FOR BABCOCK AND WILCOX
PILOT TEST PROGRAM
(1967-1969)
fronliule Anilyili t Dry
Volatile natter
Fined Carbon
Aih
BTU/lb Dry
Ultliute Anilyeli t Dry
Cerbon
Hydrogen
Nitre-Ren (Calculated)
Sulfur
An*l
Oxygen (Difference)
Sulfur Forma X Dry x«* Sulfur
Fyrllle
Sulfece,
Organic (Difference)
Total
Chlorine 1 Dry
Alh Conpodtlon X
SlOj
Fe20]
T102
C»0
lta?0
K20
SO) (CrevlBOlrle)
Aih Hiilon Teirpereture *f*
Atmoapnere
ss
SH
FT 1/16
FT (fUt)
B-2279L
lac Shipment
37.4
47.4
11.2
12.1)0
67.}
4.6
1.3
4.3
D.2
7.1
2.7
0.1
1.5
4.3
0.02
39.
16.
27.
0.
9.
0.
0.
2.
Red. Oxtd.
1940 2240
1990 2300
201.0 2340
2J40 2460
2170 2)10
STANDARD TEST COALS
oxsorr STOW RAW
C-13167
2nd Shipment
1st Box
38.6
48.2
13.0
11.160f
68.7
4.9
1.4
4.2
12. B
1.0
1.4
0.9
1.9
4.2
0.07
36.
13.
28.
0.4
9.0
O.J
0.6
2.3
12.9
Red. Oxld.
19SO 2230
2000 2340
2040 2380
2310 2300
2390 2)40
C-13311
2nd Shipment
2nd Box
17.6
47.9
14.1
-
-
"
"
4.2
-
mm
e.
-
Re . Quid.
e*
-
< 13273
Orient 13
Hint*.
35.3
&9.S
14.7
12.150
-
-
-
0.8
<0e 1
0.6
1.4
--
12.
24.
9.0
0.6
6.0
1.0
1.4
1.9
"
Rrd. Oxld.
2070 2200
2270 2410
2330 2460
2740 2670
2810 2860
TV
C- 131 74
AtXlnaon
Mine .
14.4
46.7
IB. 9
11.360
-
-
«
2.6
0.2
1.2
4.0
-
42.
17.
OJ4
13.
0.9
0.0
1.6
"
Red. Oxld.
1950- 2160
1990 2220
2020 2250
2270 24ti&
I4BO JJ4B
A TEST COALS
C- 13279
Old Ben 124
Mine
IB. a
10.2
11. 0
12.760
-
-
"
1.3
40. i
1.3
2.6
"
41.
22.
17.
0.3
6.0
1.0
1.3
l.T
"
Red. Oxld.
2070 2270
2140 2360
2180 2410
2 ft 50 2670
2780 27)0
C-I31I9
Little Joe Mine
37.0
46.9
16.1
11,980
1.9
0.1
1.6
1.6
0.01
11.
24.
18.
0.)
1.0
1.0
0.)
2.4
Red. Oxtd.
1990 2440
2170 2480
2240 2500
2600 2710
2710 28110
LICMITC
COAI.
C-IJ176
Korth Ikihnl.
1 Ixnl t e
43.3
48.0
8.7
11.020
61
4
1.
0.
1.
19.
O.I
jQ I
0.6
O.I
--
2).
8.
11.
0.4
24.
9.0
1.0
0.4
"
*ed. 0*1 il.
2270 2280
2350 2)20
2)80 2)40
24)0 2)70
2550 Z1IO
HIM!
SVI FU*
COAL
c-iim
Pr'l-otly Colt
32.4
It 0
12.6
9.3)0
49 0
i!o
11.2
32.6
0.)
10.9
0.1
7.0
1J.2
-
10.
18.
o!4
1.0
0.4
0.1
1.1
*rd null).
l«"0 2)70
20/0 IMO
2110 7S50
:thO 2570
IMO 7580
tn
en
lC«lc. »cu (DuLon|)
ASTH D»l(n>lloni
-------
TABLE XIX
PARTICLE SIZE ANALYSES FOR COTTRELL ENVIRONMENTAL
SYSTEM'S FIRST TEST SERIES
(December, 196'9)
eur.ulntivo Per Cent BY Ueiqht taaa Than Indicated Particle Dinnoter
W».llf
i
la
!P.
3 A
:.-,
1U
5 A
H.-hco
2i>
5.8
10.2
6.4
2.8
4 .0
3.0
'- : | ' . 2
?\
-.;.
JO
.A
43
J*\
',»
j;>
3\
'a
:T
IA61D
2 A
.l'^.J
3Ai<\
5A150
1A£13
2 A
3/U47V
5A65B
« '.
11.9
10. 6
12.0
12.0
9.2
11. 5
13.8
25.4
9.3
13.6
2.2
3.8
Mch. Inlet
>'cch. Inlet
Mcch. Inlet
Mcch. Inlet
Ilccli. Inlet
Nccli. Inlet
P[)tr. Inlet
Pjitr. Inlet
Tptr. Inlet
Pntr. Inlet
P|itr. Inlet
Pplr. Inlet
Pptr. Inlet
Pptr. Outlet
l>]>tr. Out lot
Fplr. Outlet
P[>tr. Outlet
r'cch. coll. Hopper
1. C.-tch
i:ccli. coll. iio^j.cr
& Catch
Koch. Coll. Hopper
t Catch
llcch. Pptr. Hopper
Electrostatic
Collector
Elect. Pptr. Hopper
elect. Pptr. Hopper
t Catch
Elect. Pptr. Hopper
& Catch
I
(J\
-------
TABLE XX
PARTICLE SIZE ANALYSES FOR COTTRELL ENVIRONMENTAL
SYSTEM'S SECOND TEST SERIES
(July, 1971)
! 0.
6
e
14
r3
T.
-a
_ -^~-
2
2
7
3
1
3
4
f.
S
5
1
C
6
a
G
TO
11
".
i M
:-i
! !4
1 15
1 15
i "
Cumulative Per Cent Dv Melqht Less Than Indicated Particlb Dinircter
Dohco
?!.
16.3 ^_
IS. 2
10.8
15. 5
11.0
lu.U
9.7
e.2
9.0
Iff. E
7.0
G.-;
3.G
7.8
0.0
4.4
7.0
7.0
~~s.V~
r,.o
4.0
5.2
rf.2
-
5.0
6.0
j.u
4.0
9.2
J.O
7.4
3.8
3.5
5 u
. 42.0
47.5
20.0
44.0
43.0
2(1.0
27.5
33.5
3C.O
10.0
32.4
39.4
1C.1
46. 0
40.D
20.2
39.0
31!. 0
22.4
40.0
34.4
21. C
47.0
" -
31.0
3U.O
J1.2
20.0
40. 0
29. G
25.0
32.0
23. G
10u
61.5
67. 5
42.0
65.0
65. 0
43.5
42.5
55.8
03.0
82.5
54.0
71.0
~~4l!o"
81.2
72.4
44.0
74.0
72.0
4G.O
75.8
CO. 4
44.0
79.6
65.3
75.0
71.8
41.0
7S.8
GO.O
4G.4
70.0
C3.0
20 u
75,0
79.0
49.0
77.0
7G.O
52.0
51.0
7G.O
95.5
93. G
74.0
92.0
67.0
95. 5
92.4 .
70.0
94 .0
90.0
71.0
95.0
08.2
68. 4
95.0
88.8
94. G
"91 .-§
G5.2
9G.O
05.5
G9.6
93.5
91.0
30 u
_J&>£
82-.0
52". 0
111.5
ec.o
!>5.0
54.5
84.8
9G.9
94.9
83.0
97.4
80.0
97.4
97.2
82.0
98.2
94.2
83.8
98.6
93.0
00.5
98.0
93.0
07.5
96. 6
77. G
98.9
33.6
80.5
98.2
97.0
Sieve
44u
. -?.?,!__
94.3
62.5
97.1
96.0
G4.5
62.4
92.9
93. G
90.6
90.4
9V. ^5
90.0
98.3
93.5
83.9
95.4
39.1
92.1
97.3
99.4
89.0
99 .'3
65.7
oo. S
9G.4
90.3
' 96.6"
86.2
9~9'.5
SS.L
91.6
98.7
98.3
74u
?}s5 -,
99.1
64.4
39.2
97.9
82.2
78.5
97.1
54. G
ri.e
96.2
|9.5
94 .6
98.6
94.3
92.1
95.8
59 1
94.4
98.3
99.7
95.6
99.5
C9.J
94.1
97.2
93.2
97. E '
92.9
99.5
Vj.S
95.1
98.9
9G.O
149u
-lftPj-9
100.0
79.2
99.9
99.9
85.6
82.4
99.41
95.8
93.2
99.3
99.8
99.15
99.04
95.4
9S.S
97.2
76.2
98.9
98.8
99.9
98.1
99.87
97.8
so./
97.5
99.8
'99'. 9
95.5
99.7
CO . ^
98.9
99.0
99.5
297u
100. 0
100.0
94.0
100.0
100.0
96.0
95.5
99.78
97.6
96.9
99.7
99.9
99.76
""gY.V"
97.9
93.3
98.9
07.0
99.6
99.2
'99N.96
98.8
99.92
99.1
99.4
97.8
99.9
99.9"
98.6
99.7
99.94
99.4
93.2
99.5
SP.CR.
qm/ce
2.68 '
2.G1
2. GO
2.51
2.34
2.54
2.50
2.85
2.80
2.75
2.49
2.48
2.36
3.07
2.56
1.89
3.11
2.86
2.70
2.30
1.38
2.39
2.G6
2.31
2.G3
2.50
" 3.11
2.53
2.91
2.91
2.48
2.5S
2.50
Sample
Source
Limestone Feed Tank
Lines tono Feed Tank
Limestone Feed Tank
Limestone Feed Tank
Limestone Feed Tank
Limestone Feed T^nV.
Limestone i'ccd Tank
Koch. Inlet
Pptr. Inlet
Pptr. Outlet
l-'cch. Inlet
Pptr. Inlet
rptr. Outlet
Pptr. Inlet
Pptr. Outlet
Koch. Inlet
PptrT Inlet
Pptr. Outlet
Mcrh. Inlet
rptr. Inlet
Pptr. Outlet
"ech. Inlet
Pptr. Inlet
rptr. Outlet
Pptr. Inlet
Pptr. Inlet
Pptr. Inlet
Potr. Outlet
!'.ceh. Inlet
Pptr. Inlet
Pptr. Outlet
Ncch. Inlet
P,)tr. Inlet
Ppir. Iilct
-------
TABLE XXI
PARTICLE SIZE ANALYSES FOR COTTRELL ENVIRONMENTAL
SYSTEM'S SECOND TEST SERIES
(July, 1971)
1
:o.
17
13
i l!i
U
?o~*
*^"tf~~
23
23
24
2 >'i
20
26
2C
27
27
21)
' / >: "
2'J
JO
30
20
32
32
33
33
2
3
0
0
3
It
IS
Cumulative Por Cent By Weight Less Than Indicated Particle nimrotar
Dahco
7 H
5.0
6.5
11.0
u.5
li.i
13.0
1G.O
15.0
14.0
13. Z"-
2.8
11 .2
7.8
1.'.
13.2
5.0
10. G
.12.2
9.6
9.8
lb.2
1C.O
4.8
4.4
3.1
2.3
3.C
2.B
2.2
3? 2.fe
33
3.0
Su
29.8
33.0
42.0
:o.o
52.0
SI. I!
06. 0
55. 6
57.2
52.2
44. C
il.8
3U.O
25.6
b'J.G
37.8
50.4
70.0
31.6
40.0
44 .0
48.4
14. C
14.2
12.5
10.2
13.0
11.8
11. C
12.6
10.8
lOii
62.0
73.0
C3.B
52.0
U2.0
82.0
85.0
04.0
G4.5
79. C
77.0
83.0
C9.6
Cl.O
1
85. G
70.4
79.6
90.2
.o
80.4
G4 .0
30.8
20.2
27.6
;G.O
22.2
27.0
22.4
23.0
2
99.2
94.7
35.7
91.1
67.8
93. S
87.0
87. G
82.2
87.0
149g
99.4
99.3
98.6""
99.1
53.0
99~."lT"
99.4
99.2
99.5
90.6
99.4
99.5
99.0 1
97.6
99.5
90.9
7. .1
90.7
99.1
99.3
99 .5
98.2' s
99.8
99.3
99. G
99.7
99.9
99.4
99.2
93.5
9G.1
94.0
96.3
97.3
297u
99.8
99. G
99.6
99.77
99.77
99TGT"
95. 7
99.4
99.9
90.8
99.8
99.7
99.4
98.0
99.8
'
99.2
19. G
99.1
99.5
99.6
99.7
99.8
99.9
99.7
99.9
99.99
100.00
99.99
99.93
99.92
99.5
99.6
99.7
99.7
SP.CR.
cim/cc
2.47
2.09
_
2.37
2.51
2" 62
2.63
2.67
2.21
2.75
2.76
2.71
- 4.33
2.63
2.89
2.83
2.37
2.6G
3.02
3.93
2. 62
2.69
3.11
2.85
2.9C
2.1i2
2.49
T.71
2Y03"
3.04
2.74
2.60
Saipylo
Source
rptr. Inlet
Pptr. Inlet
Fptr. Outlet
Pptr. Inlet
Pptr. Inlet
Pptr. Inlet
Pptr. Inlet
rp'-r. 7nlLt
rptr. Outlet
Fptr. Inlot
Pptr. Outlet
Pptr. Inlet
Pptr. Inlet
Pptr. Outlet
Tptr. Inlet
1'ptr. Outlet
Pptr. lilct
Pptr. Ojtlct
Pptr. Inlet
Pptr. Outlet
Pptr. Inlet
Pptr. Outlet
Ilcc'i. I-ict
Pptr. Inlet
Ilecli. Inlut
Potr. Irlet
."cch.tnical Hoppers
"*~ -B- Side
1. 2. S, 6
I
Ul
CO
I
-------
TABLE XXII
PARTICLE SIZE ANALYSES FOR COTTRELL ENVIRONMENTAL
SYSTEM'S SECOND TEST SERIES
(July, 1971)
Hun
15
1C
H
17
10
21
22
23
"24
Cumulative Per Cent By Weight Less Than Indicated Particle Diarreter
Hah co
2u
17.8
16.8
Ib.B
16.2
17.2
14.0
17.5
17.5
18.0
5u
60.4
58.0
bO.G
61. G
62.0
54.0
61.8
57.8
53.0
lOu
88.2
80.0
87.0
83.0
88.2
89.0
86.0
82.8
32.3
20n
98.2
97.4
9.7.2
97.8
98.1
92.6
96.2
95.0
94.2
30w
99.58
99.3
99.1
99.2
99.5
94.5
93.4
97.9
5S.3
Sieve
44u
99.9
99.8
5'j.d
99.5
99.9
96.9
98.3
98.1
97.3
74g
99.9
99.94
5*9.3
99.6
99.99
97.6
98.7
98.8
99.2
149u
100.00
99.96
?<> .95
99.7
100.00
99.6
99.5
99.8
59.7
297vi
100.00
100.00
99.95
100.00
100.00
99.95
99.8
99.91
100.00
SP.GR.
qn/cc
2.63
2.29
2.43
2.65
2.75
2.16
2.46
2.55
2.56
Sanple
H* O *
O* *T3 ft
O rr
M 1
U H-
M 0
« D
H-
M
.» *a
i -0
U> CO rr
* *(
c\
''
-------
TABLE XXIII
LABORATORY AND IN-SITU RESISTIVITY MEASUREMENTS
FOR COTTRELL ENVIRONMENTAL SYSTEM'S FIRST
TEST SERIES
(December, 1969)
r.un
:!o.
1A
13
3 A
!A
SA
SB
1A
ID
3 A
4A
',D
'jh
50
2 A
3 A
3B
1A
1D
SA
jn
2A
2 A
30
13
53
Sample-
Source
A!l Inlet
All I->lot
All In lot
A!l Ii let
All Ir.let
A'l InlcL
r.c
MC
i:c
MC
KC
i:c
MC
Pi>tr. Inlot
P|>tr. Inlet
I'lJtr. Inlet
P[>tr. Inlrt
P[»tr. Inlet
I'pLr. Inlet
Ppcr. Inlot
PnLr. Out Lot
Pptr. Outlet
Pptr. Outlet
P^tr. Outlet
Putr. Outlet
tab Kdflisfclvltv - OI1M CM (G« Moisture in GB9)
Z50»F.
I.lxl0ij
1.4x10"
1.4xl013
Z.lxlO1''
9.0xl0li!
l.SxlO12
S.lxlO1'4
1.2xl012
1.4xl012
l.CxlO12
l.GxlO12
2.3*10"
o.oxio12
3.4X1012
6.8tl012
1.2JC1012
l.OxlO12
1.1-1011
l.lxlO12
3*?T
1.4X101'4
l.Sxlfl"
2.Sxl012
9.0xlOLi
l.«xl OiJ
1.7xl01'
1.3xlOli
g.oxio11
5.1x]OiL
S.OslO11
G.OxlO11
l.OxlO12
l.CxlO12
l.SxlO12
l.flxlO12
3.9xl011
S.'.xlO11
2.7N1011
4.5<10ii
430«r'.
l.CxlO11
1.6x10"
2.3S10111
6.BX1010
l.lxlO12
4.5M010
l.lxlO12
5.4X.1011
S.lxlO10
l.lrlO11
9.0K1010
2.7X1011
1.7«10"
l.CxlO11
1.7X1011
l.SxlO11
1 .4XJO"1
e.C'iu10
1.6x10*°
S50°F
l.lxlO1"
l.OxlO11
1.2X1010
9.0xlOU
1.2X1011
G.BxlO9
3.4x10"
4.5xlOi0
S-OxlO3
9.0xl010
S.OxlO9
l.BxlO1"
S.OxlO3
D.OxlOJ
l.lxJO10
1.4xl010
1.5X1010
c.e<3o9
3.5-109
650'F.
1.1x10*
1.2xl0lu
9.0xlOK
9.0xlOU
l.OxlO1"
1.2X109
C.UxlO10
C.BxlO9
9.0x10°
5.4x10°
O.OxlO8
l.SxlO9
l.lxlO9
1.4x10^
l.lxlo'J
1.3xl09
1.2xl09
6 OxlOU
C.8'10°
Temp
r
509
510
520
520
G34
G3D
293
311)
293
312
302
!n-Situ
Resistivity
I.«xl010
4.3X1010
l.JxlO10
1.2X1010
3.7xl09
l.lxlO10
4.8xl09
2.1xL010
2.G.S1011
4.7;-.1010
S.OxLO11
o
I
-------
TABLE XXIV
LABORATORY AND IN-SITU RESISTIVITY MEASUREMENTS
FOR COTTRELL ENVIRONMENTAL SYSTEM'S SECOND
TEST SERIES
(July, 1971)
"o.
10
20
:i
22
23
7 \
~'j
33
31
1
2
j 3
;
3
0
r.
»
10
11
14
10
Id
17
' ^i
i >
1->
27
i < .
30
Sar.nl c
Pni-. Inlet
?p:r. I-lct
P:.i.r. Inlet
Pi Ur. Inlet
t>; nr. Inl = b
p- :r . inl'-t
I'.'.r. I-ilut
P|-'..r. liilt-L
I'f.tr. Iii]«.-c
Pi tr . Inlet
1',-Lr. lnl< L
Ppi.«-. Inl"t
P:>£r. Inlet
P!'l.r. Jnl"!.
fptr. Inli:t
!. Li . Jnlot
I'l Lr. In]ot
1», S.r. Inlet
I': f . lnl=t
!; ir . I :il us
li r . In! r t
\^:.c. I-ilct
200"F.
3.4xl013
4.SxlC10
9.0xl012
l.OxlO13
6.8xl012
D.OxlO12
3.0/.1012
3.0, SO11
2.7X1012
Lab Re
250"F.
5.4xI013
2.1>.1013
1.4xl014
5.4xl013
6.8xl013
2.7xl014
--
__
sistivity -
300-F.
4.5xl013
2.7xl013
2.3xl013
2.7x3013
4.5xl013
i.-sxio14
g.oxio13
C.SxlO13
3.9xl013
OIIM-CM (61
350°F.
3.9xl013
2.3xl013
1.4xl013
2.7xl013
3.9xl01J
9.0vlo13
__
__
__
Moisture ii
400"F.
5.4xl012
9.0xl012
4.5xl012
9.0xl012
2.7xl013
e.ovio13
1.4xl014
1.4xl014
5.4xl013
i Gas)
500°F.
3.4xlOX1
5.4X1011
2.1xlOU
1.4xl012
2.7xl012
9-OxlO13
,3.4xl013
1.4xl014
3.9xl013
SOO'F.
1.9xl010
5.4>:1010
1.3xlOi0
l.lxlO11
9-OylO11
I.«vl013
1.4>:1013
6-OxlO13
6.8xl012
°F
260
330
260
322
323
3?8
320
325
?60
315
312
250
325
2G3
323
285
280
2SO
.320
320
262
270
2G2
310
270
326
272
2G3
320
Resistivity
2.8xl01C
1.6<10-i
1.4.xlOU
1.8xlOil
3.7xlC12
2. ?.c!Ci2
S.OslC12
8.3X1011
9-lxlO11
l.lxlO11
1.2- 1C"1
5.7X1010
l.CxlO11
2.1x.CaI
5.6-10"
1.6X1011
3.8MP11
6.7X1011
6-lxlO11
8.9-xlO11
I.«xl011
2.9xl012
2.3X1011
S.GsJC11
1.4xlOi2
2.4X1011
1 .SxlO11
4.3x10^
9.0xlOi2
-------
TABLE XXV
LABORATORY AND IN-SITU RESISTIVITY MEASUREMENTS FOR
COTTRELL ENVIRONMENTAL SYSTEM'S SECOND TEST SERIES
(July, 1971)
Run
No.
4
9
10
25
30
Source
Sample
Pptr. Inlet
Pptr. Inlet
Pptr. Inlet
Pptr. Inlet
Pptr . Inlet
Lab Resistivity - OHM-CM (6% Moisture in Gas)
200°F
2.7xl09
4.5x10°
3.3X1010
4.5xl012
3.9xl012
300°F
6.8X1011
2.7xl09
9.0X1011
3.9xl013
3.4xl013
400°F
2.5xl012
9.0xl010
1.3xl013
9.0xl013
4.5xl013
500°F
1.6xl012
1..3X1010
3.4xl012
2«7xl013
l.BxlO13
600°F
2.7X1011
3.0xl09
2.5X1011
5.4xl012
3.0xl012
650°F
1.4xlOU
l.SxlO9
g.oxio10
3.9xl012
'l.SklO12
Temp
°F.
325
280
260
270
320
In-Situ
Resistivitv
l.SxlO11
3.8X1011
6.7X1011
1.4xl012
9.0y.l012 '
i
. . j
-------
-03-
TAJJI.I XXVI
LABORATORY AND IN-SI "I I) R I S 1 S'l I VJJI Y Ml ASH RI Ml.Ml S
FOR HABCOLK AND WI l.COX P 1 LO'I TI-ST I'RCK.RAM
(1967-1969)
Legend
e
o
A
A
0
0
H
D
Test
No.
67- M
68-4-1
68-7-10
68-4-11
68-5-2
69-2-11
69-4-2
69-4-4
69-4-5
69-4-6
69-:-8
69-4-13
69-4-15
69-4-19
69-4-21
69-4-25
69-5-1
69-S-S
69-7-7
69-11-11
69-11-13
69- .2-5
Coal
No.
B- 22791
C-13167
C-13273
C-13274
C-13279
C- 13319
C-13376
C- 13378
Laboratory Resistivity, onn-on
300 F
1 ?
3.2x10"
4.0xl012
l.SxlO13
.
.
-
2.SX1012
3.4xl012
2.7xl013
2.W2
-
1.2X1012
2.1X1012
-
4.SX1011
.
-
4.5X1012
l.SxlO11
-
8.4xl012
600 F
in
6.7xl010
2-OxlO10
3.9xlOH
.
.
-
8.4x10°
6.8xl09
6-SxlO11
3.9xl010
-
6.8xl09
-
4.5xl09
-
6.8xl09
.
-
6.8xl09
1.4xl09
-
S.4xl09
AC In Situ
Ten^j
-
9.0X1010
l.SxlO13
.
.
-
l.OxlO12
2.SX1012
2.7xl013
2.5xl012
-
l.Oxl-,12
-
2.1X1012
-
4.0xl011
.
-
4.0xl012
l.SxlO11
-
S.OxlO12
In Situ Resistivity, ohm- or.
Temp, F
-
SOS
299
460
425
300
' 270
310
300
305
300
310
310
300
320
310
305
355
313
400
365
295
Resistivity
.
l.OxlO10
2.7xl010
1.6X1010
4.3xl09
1.9X1011
1.7xlOU
1.6X1011
2.6X1010
2.6X1010
1.3X1011
l.lxlO11
l.SxlO11.
3.4xlOU
4.4X1010
4.6X1011
S.lxlO11
7.2X1010
S.7xl010
3.2xl010
6.2.X109
1.4X1012
o
A
A
Standard Test Coal
Colbert Steam Plant (TVA)
Orient #3 Mine (TVA)
Ackinson Mine (TVA)
Old Ben #24 Mine (TVA)
Little Joe Mine (TVA)
-------
TABLE XXVII
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON
SAMPLES TAKEN DURING THE FIRST CES TEST SERIES
Test
Date
12-11-69
2-11
12-11
12-11
12-12
12-12
12-12
2-13
2-13
2-13
2-13
2- 14
2-14
12-14
12-14
2-14
2-14
2-15
2-15
2-15
2-15
12-15
! ' - ^
' 1_-JL.">
1
Sample
Identification
MC Inlet
ML" Hopper
ESP Hopper
MC Inlet
MC Outlet
M C llonpcr
LSP Honper
'V Cutlet
V!C Inlet
MC Out let
M T Hopper
MC Inlet
MC Outlet
MC Inlet
MC Outlet
MC Hopper
ESP HopDcr
VC Inlet
MC Out let
'!L Inlet
MC Outlet
M C II o > P c r
LSP l!o-jper
-\K Inlet
CES
Test No .
1A
IB
2A
3B
4B
4B
3A
3A
4A
4A
-
5A
5A
5B
5B
TVA
Lab No.
C-34
C-48
C-53
C-35
C-41
C-49
C-54
C-43
C-38
C-45
C-51
C-36
C-42
C-37
C-44
C-50
C-55
C-39
C-46
C-40
C-47
C-52
C-56
C-57
%
Si02
46.8
46.3
49.9
46.8
48.0
45.6
47 .4
49. S
46.5
50. 1
46.0
47 .6
50. 1
47.3
50.6
45.6
50.3
43 .4
50.1
42 .6
49.6
43.6
49. S
47.4
%
A1203
20.9
20.2
23.2
20. 1
20.7
20.0
21 .4
24 .1
20. 9
23. 7
20.6
21 .9
24 .5
21 . 1
24 .0
19.9
24 .0
19.8
23.4
19. 3
23.0
18.5
22.9
21.0
%
Fe2°3
16.7
16.9
10. 6
16.3
14.2
18. 2
13.6
9.7
13 .6
10. 1
14 .6
16 .4
10. 1
16 .0
10. 2
17.9
10. 1
25 . 1
14 . 1
22 .0
14 . 1
24 .0
12.6
13.5
%
CaO
7.0
7 .1
4 . 7
6.4
5 .4
6.7
5 . 3
4 .5
6 .7
4.5
7 .7
6.6
4.0
6 .3
4 . 1
6.9
4 .2
5 . 5
2 .4
3. 8
2.9
4 .6
3 . 1
5 .9
%
MgO
1.0
1.0
1 .2
1 . 1
1 .0
1 . 1
1 . 2
1 .3
1 .0
1 .4
1 . 1
1.0
1 .5
0.9
1 . 2
1.0
1 .3
1 .0
1.2
0.9
1 .3
1 .0
1 .4
1 .2
%
Ti02
0.7
0.9
1 . 1
0.9
1 .0
0.9
1 .1
1 . 0
0.7
0.9
1 .0
0.7
1 .0
0.7
1 .0
0.8
1 . 1
0.8
1 .0
0.9
1 .0
0.9
1. 1
1 . 1
%
Na20
0.8
0.6
0.8
0. 7
0.6
0. 5
0.6
1 .0
0.9
1 . 0
0.6
0. 7
0.9
0.8
1 .0
0. 5
0.8
0.4
0.5
0.4
0. 5
0.3
0.6
0. 7
%
K20
2.2
1 . 7
2 . 0
2 . 2
2. 3
1 . 7
1 . 9
2 . 3
2. 0
2 . 1
1 . 7
2 .0
2. 3
2 . 0
2 . 2
1 .4
1 . 9
1 . 8
2.0
1 . 8
1 . 9
1 . 4
1 . 9
1 . 7
%
S°4~
1.3
1 .6
2 .8
1 .8
2.5
1 . 5
2 .5
1 . 2
1 .0
1 .2
1 . 1
0.9
1 .6
1 . 1
1 .5
0.8
1 .7
0.9
1 .6
0. 7
1 . 3
0.8
1 .6
2 . 2
%
Loss on
Ignition
2.2
2.6
2.7
3 .9
2.8
2.3
2.8
3. 1
4 .6
2 .7
3.1
2.2
2.5
2.4
2. 1
4.0
2 .8
3.2
2.6
5.0
3.0
3. 1
2 .5
3. 2
-------
TABLfc XXVIII
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON SAMPLES
TAKEN DURING THE SECOND CES TEST SERIES
Test
Date
7-10-71
it
n
!
ii
7-13-71
it
n
n
n
7-14-71
ii
ii
n
n
7-15-71
n
ii
7-24-71
n
Sample
Identification
MC Inlet
MC Outlet
ESP Outlet
MC Hopper
ESP Hopper
MC Inlet
MC Outlet
ESP Outlet
MC Hopper
ESP Hopper
MC Inlet
MC Outlet
ESP Outlet
MC Hopper
ESP Hopper
MC Outlet
MC Outlet
MC Outlet
MC Inlet
MC Outlet
CES
Test No.
2
2
2
2
2
6
6
6
6
6
8
8
8
8
8
9
10
11
14
14
TV A
Lab No.
C-883
C-881
C-882
C-774
C-773
C-895
C-893
C-894
C-790
C-789
C-898
C-896
C-897
C-794
C-793
C-899
C-901
C-903
C-907
C-905
% S =
<0.1
\
?
% S04 =
6.4
7.8
6.3
4.9
6.7
4.8
5.6
4.0
2.6
4.6
5.3
6.6
5.0
4.4
4 .7
4.4
4.5
5.2
5.4
7.3
% S0? =
6.7
10.8
2.0
0.1
0.1
7.8
10.5
3.0
0.3
1 .1
9.6
12.3
8.5
0.2
0.5
<0. 1
11.7
7.9
8.2
7.9
Total
%S
4 .8
6.9
2.9
1.7
2 .3
4.7
6.1
2.5
1 .0
2.0
5.6
7. 1
5.1
1 .6
1.7
1 .5
6.2
4 .9
5 .1
5.6
\ CaO
30.8
28.6
19.9
32.5
24.2
33.0
30.0
30.2
22.0
32.5
33.3
31 .4
22.1
37.5
24. 1
4.5
23.5
31 .6
35 .6
33.9
-------
TABLE XXVIII (continued)
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON SAMPLES
TAKEN DURING THE SECOND CES TEST SERIES
Test
Date
7-24-71
it
it
7-24-71
ii
ti
ii
it
7-22-71
7-22-71
7-20-71
it
ti
ii
ii
n
7-20-7]
ti
ii
n
Sampl e
Identification
ESP Outlet
MC Hopper
ESP Hopper
MC Inlet
MC Outlet
ESP Outlet
MC Hopper
ESP Hopper
MC Outlet
MC Outlet
ESP Outlet
ESP Hopper
MC Outlet
ESP Outlet
ESP Hopper
MC Outlet
ESP Outlet
ESP Hopper
MC Outlet
CES
Test No.
14
14
14
15
15
15
15
15
17
18
19
19
19
20
20
20
21
21
21
22
TVA
Lab No.
C-906
C-814
C-813
C-910
C-908
C-909
C-817
C-816
C-912
C-915
C-917
C-918
C-830
C-919
C-920
C-832
C-931
C-922
C-835
C-923
% S =
<0.1
t
7
% S04 =
5.6
4.5
5.2
5.6
6.9
5. 5
4.3
6.0
4.4
5.5
0.8
4.4
0.6
0.8
7.2
0.8
0.8
5.3
0.8
1.6
% so3=
5.0
0.5
0.9
7.7
10.8
5.5
0.6
1 .1
6.5
7.5
0.3
3.7
0. 1
0.9
4.4
<0.0
0.2
3.0
<0. 1
0.6
Total
%S
3.9
1 .7
2.1
5 .0
6.6
4.0
1 .7
2.4
4.0
4.8
0.4
2.9
0.3
0.6
4.2
0.3
0.4
2.9
0.3
0.8
% CaO
28.0
46.5
24.6
36. 7
34.7
26.6
49.3
31 .4
26.9
33.6
1.4
9.8
1 .7
2.2
13.4
2.2
1 .1
11 .8
1 .4
5.6
-------
TABLE XXVIII (continued)
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON SAMPLES
TAKEN DURING THE SECOND CES TEST SERIES
Test
Date
ii
ii
ii
ii
"
"
ii
ii
7-19-71
7-23-71
H
7-21-71
1 1
II
7-26-71
ri
li
li
Ii
Sample
Identification
ESP Outlet
ESP Hopper
MC Outlet
ESP Outlet
ESP Hopper
MC Outlet
ESP Outlet
ESP Hopper
MC Outlet
MC Outlet
MC Outlet
MC Outlet
MC Outlet
MC Outlet
MC Inlet
MC Outlet
ESP Outlet
MC Hopper
ESP Hopper
CES
Test No.
22
22
23
23
23
24
24
24
25
26
27
28
29
30
32
32
32
32
32
TVA
Lab No.
C-924
C-838
C-925
C-926
C-842
C-927
C-928
C-846
C-929
C-931
C-934
C-936
C-938
C-940
C-944
C-942
C-943
C-873
C-872
% S =
<0.1
\
^
% S04~
3.7
0.7
1.9
2.5
1 .6
4.0
3.7
3.0
5.9
6.0
5.3
8.4
6.9
6.7
6.5
8.7
7.2
4.5
7. 1
% S0^ =
1. 1
<-0.1
1 .1
1.4
^0. 1
1 .9
1.4
ziO. 1
8.6
7.6
8.5
2.8
4.1
5.0
4 .5
9.7
10.6
0.4
0.3
Total
%S
1 .7
0.3
1 .1
1.4
0.6
2.1
1 . 8
1.0
5.4
5.0
5. 2
3.9
3.9
4 .2
4.0
6.8
6.6
1 .7
2.5
% CaO
6.2
2.8
5.9
16.2
9.8
18.8
17.6
15. 1
26.0
30.8
28.8
38.6
28.8
27. 2
27.7
27.7
23.5
29 .7
24 .9
-------
TABLE XXVIII (continued)
SUMMARY OF CHEMICAL ANALYSES PERFORMED ON SAMPLES
TAKEN DURING THE SECOND CES TEST SERIES
Test
Date
7-26-71
11
ii
M
ii
Sample
Identification
MC Inlet
MC Outlet
ESP Outlet
MC Hopper
ESP Hopper
CES -
Test No.
33
33
33
33
33
TVA
Lab No.
C-947
C-945
C-946
C-877
C-876
J, Q =
8 i>
<0.1
1
% S04 =
6.0
8.3
6.4
4.6
8.8
% SO-T
6.7
7.9
10.8
0.3
0.2
Total
%S
4.7
5.9
6.4
1.6
3.0
% CaO
25.5
26.3
21 .0
31.6 1
26.6
CO
I
-------
TABLE XXIX
CHEMICAL ANALYSES OF LIMESTONE USED DURING
SECOND CES TEST SERIES
Test
Date
7-10-71
7-24-71
7-26-71
Sample
Identification
Limestone
98% Gyroclass
(Fine)
Limestone
20% Gyroclass
(Coarse)
Limestone
20% Gyroclass
(Coarse)
CES
Test No.
2
14
32
TVA
Lab No .
C-772
C-812
C-871
% H20
(105°C)
0.1
<0.1
<0.1
%
CaO
54.9
54.9
55.0
%
MgO
0.2
0.2
0.2
\
C03~
55.6
55.7
55.0
VO
I
-------
-70-
VI. ANALYSIS AND DISCUSSION OF TEST RESULTS
The main sources of data used in the analysis and corre-
lation of the test results are two CES test programs at
Shawnee (December, 1969 and July, 1971), two TVA test
programs (July-August, 1969 and June-July, 1970), SRI test
program at Shawnee during July, 1971, Research-Cottrell,
Inc. tests at a midwest power station during limestone
injection tests (February, 1967) and Babcock and Wilcox
pilot plant study (1967-1970).
1. Electrostatic Precipitator Performance
The precipitator is a Research-Cottrell, Inc. design
installed on the unit 10 steam generator at TVA
Shawnee Station, Paducah, Kentucky. The boiler is
a B&W pulverized coal, front-fired unit rated at
175 megawatts designed to produce one million pounds
of steam per hour at 1800 psig and 1000/1000°F. The
dust collecting equipment is a Buell mechanical
cyclone designed for 65% efficiency followed by the
Research-Cottrell, Inc. precipitator designed for
95% efficiency. (Overall design efficiency is 98%).
The boiler is fired with about 60 tons per hour of
coal containing an average of 10% ash and 2.7% sul-
fur. Combustion of this fuel produces about
-------
-71-
585,000 cfm of flue gas at 300°F containing 2200 ppm
by volume S0_ and about 3 grains of fly ash per
standard cubic foot.
The precipitator shown in Figure 15 consists of two
units ("A" and "B") each including three sections as
follows:
Inlet Section of 33 opzel plate ducts
each 9" x 30" high x 4.5' long.
Center Section of 33 opzel plate ducts
each 9" x 30' high x 4.5' long.
Outlet Section of 33 opzel plate ducts
each 9" x 30' high x 6.0' long.
There are 20 magnetic impulse-gravity impact rappers
per precipitator and 4 electrical sets with automatic
control rated at 70 KV , 750 ma each.
peak
The total collecting area of the precipitator is
59,400 ft2. The cross-sectional area is 1,485 ft .
The secondary electrical readings without limestone
injection, i.e. those at the precipitator can be
estimated from the following expression using the
transformer primary readings:
Sec. KVavg< = (0.1195)(primary voltageAC Volts) (12)
-------
-72-
Sec' 'ma
= [(5.96) (primary current^ amps)-77.2j (13)
The first basis for analysis of precipitator perfor-
mance was a function of corona power input. A brief
look at theoretical considerations of this approach
follows.
A. Theoretical Considerations of Electrostatic Precipi-
tator Performance As A Function of Corona Power
1-E = Q = e~ W (14)
W = dp E0 Ep (15)
4 TT
where,
E = Fractional efficiency of precipitator
Q = Fractional loss from precipitator
A = Collecting electrode area of precipitator
V = Gas flow rate through precipitator
W = Precipitation rate parameter
d = Particle diameter
P
E = Charging field in precipitator
E = Precipitating field in precipitator
n = Gas viscosity
Combining equations (14) and (15) gives:
(16)
-------
-73-
The precipitator total corona power normally is a func-
tion of the applied voltage, precipitator size, elec-
trode geometry, and gas and particulate characteristics,
It is generally known from the literature f11^ that
as a useful first approximation, the precipitation
rate parameter is related linearly to the corona
power/ft of collecting electrode area as shown be-
low. However, there has been some conflict between
this approach and experimental results obtained dur-
ing this study. A more detailed discussion of this
matter is contained in subsequent sections.
Pc=eCAEoEp
where,
P = Precipitator corona power input
c
cf- = Precipitation parameter dependent upon
gas and particle characteristics, and
precipitator electrode geometry to a
minor extent.
Equation (16) can be rewritten as:
Thus, for similar particle size, and gas and particle
characteristics, Equation (18) shows that:
P a
In Q = -k ^. =-^W (19)
From which is obtained the relationship that:
I* = £ , or (20)
-------
-74-
W is directly proportional to precipitator corona
2
power/ft of collecting electrode, which means that
by doubling the corona power to precipitator de-
signed for 90% efficiency, one can theoretically
increase the efficiency to about 99%. However,
for practical considerations, the attainment of
the corona power in a precipitator necessary to
obtain the design efficiency requires the examina-
tion of factors which determine and affect corona
power.
(a) Particle Characteristics
(1) Particle Size - This can reduce corona
power by suppressing corona current at a
given voltage through space charge pheno-
mena. However, sub-micron particles of
fairly high loadings are necessary in
order to produce a significant affect.
(2) Electrical Resistivity - When the ash
resistivity exceeds about 10 to 10
ohm-cm, the effective corona power is re-
duced. Generally, the first effect is
increased sparking requiring a voltage
reduction in order to hold a preselected
sparkrate. Lower corona current and
power input results causing a decrease in
collection efficiency. In order to com-
pensate for the lower power, it becomes
necessary to enlarge the precipitator un-
til the total power requirements for the
-------
-75-
desired efficiency are met. Note that
the corona power per unit area of pre-
cipitator is lower, but increased area,
increases the total corona power to the
desired level.
With very high dust resistivity, a con-
dition known as "back corona" sets in,
characterized by very high currents, low
voltages and no sparking. Precipitation
practically stops and can only be restored
by lowering the dust resistivity.
On the other hand, extremely conductive
4
particles of less than about 10 ohm-cm
may be reentrained and escape collection.
(b) Gas Characteristics
CD Temperature - Increase in gas temperature
reduces gas density and reduces sparkover
potential and increases the rate of rise of
current with voltage. The result is that
for increased qas temperature, at least up
to levels of approximately 1000°F, higher
temperature operation allows increase in
power density. The affect of this increase
in power density is to elevate the precipi-
tation rate parameter, W.
-------
-76-
(2) Pressure - Small increases in gas pressure
raise the precipitator sparking voltage
proportionately while the corona current
decreases at a fixed voltage. Again, the
corona current at sparking is not signifi-
cantly changed, so that the net effect is to
increase corona power as gas pressure in-
creases and vice versa.
(3) Composition - Determines the kind of gas ions
formed in corona. Electronegative and high
molecular weight gases tend to form low
mobility ions, reducing corona current and
raising sparking voltage.
Gases such as sulfur trioxide and water vapor
condition the ash by affecting its electrical
resistivity. Sulfur trioxide is a critical
factor which depends mainly on the amount of
sulfur in the coal. However, excess air,
residence time of sulfur dioxide in an opti-
mum temperature zone, catalytic materials in
the ash such as iron oxide, etc. can also
-------
-77-
influence the amount of sulfur trioxide
present. Generally, moisture is not effec-
tive as a conditioning agent until low gas
temperatures are reached, e.g. 200-225°F,
and even then large amounts (percents) are
required, while concentrations on the order
of parts per million by volume of sulfur
trioxide can radically change precipitator
performance.
B. Correlation Of Precipitator Performance With Corona Power
Input
The data used for this analysis are taken from Tables
III through XV. The corona power inputs shown in
these Tables were calculated by the use of Equation 12
and the secondary currents taken from the electrical
set panels. The sparking rate of the precipitator was
maintained between 50 and 200 sparks/min. in an attempt
to control the power input to sparking a constant for
all tests.
In order to establish a baseline operating condition
of corona power input and precipitator performance,
only tests without limestone injection have been used
for the first correlation. In Figure 19, the precipi-
tation rate parameter W in ft/sec is plotted as a
function of corona power input expressed as a density
2
parameter, i.e. kilowatts/1000 ft of precipitator
collecting surface. From equation 20, expectations
are that the correlation will be a linear one. How-
ever, it is of interest to note that the data appear
-------
FIGURE 19
PRECIPITATION RATE PARAMETER AS A FUNCTION OF CORONA
POWER DENSITY FOR TESTS WITHOUT LIMESTONE INJECTION
0. G7r2
O
^
O
CM
O
O O
4-> LO
c
O
(3
4J
r4
a
-H
O
O
-18
n f",i
U. JO
0.40-
0.27-
-16
- 2
CES (July, 1971) Special
Low Sulfur Tests
TVA First Test Series
(July-August, 1969)
TVA Second Test Series
(June-July, 1970)
oo
I
0.1 0.2 0..3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8
Corona Power Input Density, P (Kilowatts/1000 Ft Collecting Surface)
f\
-------
-79-
to fit a curved function rather than the linear
one predicted by theoretical considerations. The
precipitation rate parameter is leveling off or even
decreasing at the higher power densities where the
value of the rate parameter is in the range of 0.5 to
0.6 ft/sec. This is somewhat higher than the typical
average value of 0.4 to 0.5 ft/sec for fly ash precipi-
tators. There may be some level of power input above
which a diminishing benefit is derived and other factors
such as gas distribution, particle size, rapping losses,
electrostatic reentrainment, etc. become the over-riding
considerations in precipitator performance. In fact,
experimental work with an electrostatic precipitator
on high pressure pipeline natural gas containing oil
contaminant has shown that at very high electrical field
strengths (five to ten times normal), a decrease in the
precipitation rate parameter occurs due to electrostatic
force reentrainment from the collecting surface.
Regression analyses of the data (42 sets) using the
equation forms,
y = a + bx (21)
y = a + b Inx (22)
y = a + bx + ex (23)
where,
y = precipitation rate parameter, W (FPS)
2
x = corona power input density, PA (KW/1000 Ft )
were performed with a GE Mark I computer. The 4 sets of
-------
-80-
special low sulfur coal tests, although plotted in Figure
19, have been excluded from the regression analyses.
The following results were obtained:
W = 0.21 + 0.25 P. (24)
A
Correlation Coefficient =0.84
F - Ratio Test Statistic = 98
W = 0.47 + 0.16 In P (25)
A
Correlation Coefficient = 0.87
F - Ratio Test Statistic = 120
W = 0.11 + 0.57 P. - 0.20 P_2 (26)
A A
Correlation Coefficient =0.89
F - Ratio Test Statistic = 75
These equations are limited to corona power density data
2
falling in the range of 0.15 to 1.5 kilowatts per 1000 ft
of collecting surface which encompasses the normal op-
erating range of fly ash precipitators. All three
equations are reasonably good representations of the data
with the quadratic form of equation (23) producing the
best fit.
-------
-81-
Previously published data^ by Southern Research Institute
for a variety of fly ash installations is contained in
Figure 20 along with a plot of the data from Figure 19.
Although there is considerable scatter in the data points,
it is quite apparent that there is a strong relationship
between the precipitation rate parameter and the corona
power input density. In the range of 0.1 to 1.2 kilo-
2
watts/1000 ft of collecting surface, there is fair agree-
ment between the published data and the results of this
report. It is postulated that the flue gas temperature
and coal sulfur which affect the particulate conductivity
are the main parameters causing the data scatter. These
variables will be examined in subsequent sections of this
report.
Another way of analyzing precipitator performance is to
plot the loss in particulate collection efficiency as a
semi-logarithmic function of the corona input power
expressed as a rate i.e. watts per 1000 actual cubic feet
of flue gas per minute. (See equation 19).
The same no limestone injection tests as analyzed above
were used for this correlation and the data are plotted
in Figure 21. A regression analysis was performed using
the form of equation 21 where,
-------
FIGURE 20
COMPARISON OF DATA FROM FIGURE 19 WITH PUBLISHED DATA OF SOUTHERN RESEARCH
INSTITUTE FOR VARIOUS FLY ASH PRECIPITATOR INSTALLATIONS REF (11)
M
0)
o ,
s
id
£o
Q) OJ
C
O
H
.p
fO
-p
0
o
M
0. 07
Orto
. J<3'
0.40
0.27
0.14
20
1 Q
1 ft _
2
U
OJ
-10 ^
c
8 -
-A
- 2
O
O
°o
fl
oO
^^^-
x
X
o
c
0
>
X
0
o<9>
2
5* «
A
X*
X
X*
<
:*,
0 0
}
o
^
o. <
x
0
>
°x
.
O
0
0
o
o
o
Q SRI Published Data
£\ Data Displayed in Figure 19
I
oc
0 0.1 0.2 0..3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8
Corona Power Input Density, PA (Kilowatts/1000 Ft Collecting Surface)
-------
-83-
y = In of the loss in precipitator collection
efficiency Q expressed as a fraction
x = precipitator corona input power, PV
(watts/1000 ACFM of flue gas)
The following equation resulted:
In Q = -1.507 - 0.0138 Py (27)
Correlation Coefficient = 0.85
F-Ratio Test Statistic = 112
Equation 27 is limited to values of precipitator corona
input power rates in the range of 15 to 215 watts per
1000 ACFM of flue gas which encompasses the normal opera-
ting range of fly ash precipitators. In Figure 22 the
previously published data of Southern Research
Institute is plotted along with the results from this
report shown in Figure 21. Again the data points are
scattered. However, the dependence of precipitator
performance on corona power input rate in watts per
1000 ACFM of flue gas treated is obvious. There is
fair agreement between the published data and results
contained in this report. A resolution of the scatter
in data requires a more detailed examination of such
variables as gas temperature, coal sulfur, particulate
size, gas velocity, rapping mode, etc. which all affect
corona power input and precipitator performance. A
-------
FIGURE 21-
. LOSS IN. COLLECTION EFFICIENCY AS A FUNCTION
OF POWER RATE FOR TESTS WITHOUT LIMESTONE INJECTION
c
o
H
-U
u
n)
CX.
H
-rH
a
r^
.-i
0
. ;
0.01
0.02
u
c
1)
H
u
H
'4--
"4-1
w
c
c;
-H
I
0)
rH
H
0
CJ
u .
0.
0.
0.
0.
0.
u J
04
05
06
08
10
0.20
0.30
0.40
0.50
0.60
0.80
1.00
0
x'
4^
9
./<#
A*
[
i «...
«^
4Sf
B*ST
U
/x
2
0^1
^/« ©
^
'og
b
^^
f-
u
O
o s
^^^
o
a
CES Fi
(Dec
CES Se
* (Jul
^ CES (J
Low
OTVA Fi
(Jul
OTVA Se
(Jur
^
^
^ 1 Eq.
rst Test
ember , ".
cond Tes
y; 1971]
'uly, 19'
Sulfur 1
rst Tesl
y August
cond Tes
le-July ,
^/
27 |
/
o
o
: Series
.969)
;t Series
71) Special
?ests
; Series
:, 1969)
;t Series
1970)
98
97
96
95
94
92
90
80
70
60
50
40
25
n
25 50 75 100 125 150 175 200 225
Precipitator Corona Input Power Rate, Py (Watts/1000 ACFM Of Flue Gas)
N
fD
n
p-
TD
H-
rt
0
h
n
o
c;
rt
P-
o
W
hh
hh
H-
n
o
O
HI
o
o
l
CD
-------
FIGURE 22
COMPARISON OF DATA FROM FIGURE 21 WITH PUBLISHED DATA OF SOUTHERN RESEARCH INSTITUTE
FOR VARIOUS FLY ASH PRECIPITATOR INSTALLATIONS - REF. (11)
oss in Precipitator Collection Efficiency, p. (Fraction)
OOOO 0 OOOOOO 0 O
0 U> N> MOOOOO
30000 o o co u> NJ
o
0
A
/
/
o
>° 82
'4
> 0
o
u
0 . Q
n 9 /
/
O
.9
n/<
22
/^i °
0 ,
L/
?«.
i n
/
9 .
o
A
w
o
0
© SRI Published Data
'
o
O Data Displayed in Figure 21
-85-
Precipitator Collection Efficiency, E (Percent)
01 oo r- vo tn ** o\ CT\ c\ (Tv cri oo t^- vo u>
-------
-86-
discussion of these parameters is contained in subsequent
sections of this report.
Data from tests with limestone injection (51 sets) are
plotted in Figure 23. The 2 sets of special low sulfur
coal have been omitted. The precipitation rate parameter
W in ft/sec is shown as a function of corona power input
density expressed in kilowatts/1000 ft of precipitator
collecting surface. Note the maximum level of input
power density attainable is about one-half that of the No
Limestone injection tests. As discussed previously, the
limestone additive has increased the electrical resis-
tivity of the particulate to the extent that the preset
optimum sparking rate of the precipitator chosen for the
test program, i.e. 50-150 sparks/min is reached at much
lower voltage and corona current input resulting in de-
creased corona power.
Regression analyses of the data presented in Figure 20
using the equations 21, 22, and 23 resulted in the
following respectively:
W = 0.15 + 0.40 P. (28)
f\
Correlation Coefficient = 0.68
F-Ratio Test Statistic = 42
W = 0.42 + 0.11 In PA (29)
Correlation Coefficient = 0.73
F-Ratio Test Statistic = 55
-------
FIGURE 23
PRECIPITATION RATE PARAMETER AS A FUNCTION OF CORONA
POWER DENSITY FOR TESTS WITH LIMESTONE INJECTION
. G7
0. 52
:-
:o Paramcte
'Sec.
0
*
c*
o
CC -U
?. ^
o 0.27
H
-^>
d
*j
a
-H
U
0.14
Brf
3
/
V
o !<
^
>v/
/'m *
^0»
B
BSB/
n,8
» o
Gs
a
no
x
Jr
^
<^ 0
a
°
o
^
^
B
I *
.....' L
J^" "*"
^
I
/
/
N
"^*"
x
rt
^ Eq. 30
-
°%
0
0 o
00
O
0
M Eq. 28
!
H Ea.. 29
D
0
O
o
0
r
n
o
0
-
1
O CES Data (July, 1971)
«-. TVA Data From The Second
** Test Series (June-July,
.1970)
(J Data Displayed in Figure 19
(No Limestone Injection)
-87-
Precipi tation Rate: Parameter, W
cm/Sec .
O CC) \O T f J O
01 r-H rH rH r-H tH GO >i rT CN C
0.1 0.2 0..3 0.4 0.5 0.6 0.7 0.3 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7
:orcr.a Power Input Density, Pa (Kilov:atts/1000 Ft Collecting Surface)
-------
-88-
W = 0.10 + 0.78 P - 0.54 P 2 (JO]
Correlation Cocf fj cj en I = 0.71
F-Ratio Tost Statistic - 24
These equations are limited to a corona power density range
2
of 0.05 to 0.7 kilowatts/1000 Ft of precipitator collect-
ing surface, which although quite low, are typical values
for a precipitator collecting high resistivity particu-
late. All three equations give equally significant data
representations with the semi-logarithmic form of equation
22 giving a slightly better correlation. The data points
from Figure 19 (No Limestone injection) are plotted on
Figure 23 for comparison. In general, it appears that
for equal corona power input densities there is no sig-
nificant difference in the precipitation rate parameter
whether limestone is injected or not. However, it should
be reiterated that the maximum level of corona power in-
put density attainable and the resultant precipitator
performance is significantly lower with limestone injec-
tion. In Figure 24 the loss in precipitator particulate
collection for the No Limestone injection tests is plotted
as a semi-logarithmic function of the corona input power
expressed as a rate (watts per 1000 actual cubic feet of
flue gas per minute).
-------
FIGURE 24
LOSS IN COLLECTION EFFICIENCY AS A FUNCTION OF
POWER RATE FOR TESTS WITH LIMESTONE INJECTION
c
o
H
-P
O
(0
O
c
a
M
u
-H
C
o
H
-P
u
o
o
u
S-J
o
-U
ti
-U
rH
a,
H
u
o
M
n
W
O
0.01
0.02
0.03
0.04
0.05
0.06
0.08
0.10
0.2C
0.3C
0.40
0.5C
0.6G
0.8C
l.OC
*
|
i
i
<
52
o / o
^ °
>v>r>
i
n
^
°8
X Q -O «
X cr
UQ°
0°
*" EQ. 31
pa '-^
o
i
1 I
V/
r>
0
O
C
>
O CES Data (July, 1971
-- TVA Data From The Sec
Test Series (June-J
1970)
^) Data From Figure 21.
(No Limestone Injec
o
o
)
oncl
'uly,
:tion)
0 25 5'0 75 100 125 150 175 200 22
99
98
97
96
95
94
92
90
80
70
60
50
40
20
M
CD
O
H-
H-
rt
rt
O
o
o
(D
O
rt
H-
O
H
P-
n
h1-
CD
D
O
O
i-1
O
o
I
00
UD
I
Precipitator Corona Input Power Rate, Py (Watts/1000 ACFM Of Flue Gas)
-------
-90-
A regression analysis of the No Limestone injection data
shown in Figure 24 was performed using the form of equation
21. The following result was obtained:
InQ = -0.868 - 0.026PV (31)
Correlation Coefficient = 0.66
F-Ratio Test Statistic = 43
Equation 31 is limited to precipitator corona input power
rates of 5 to 80 watts per 1000 ACFM of flue gas which is
the lower range of normal fly ash precipitator operation
but still typical when high resistivity ash is encountered.
The No Limestone injection data from Figure 21 are also
plotted on Figure 24 for comparison. In comparable ranges
of corona power input rates, there is fair correlation of
data regardless whether limestone is injected or not. How-
ever, the rates attainable with No Limestone injection are
much higher resulting in increased performance.
The test data with limestone injection are more scattered
than the No Limestone injection data, but still show the
strong dependence of precipitator performance on corona
power input.
-------
-91-
C. Correlation of Precipitator Corona Power Input With Process
Variable"!?
In order to make the results of the test program more
useful for predicting precipitator performance and sizing
with limestone injection, a more detailed analysis has
been made using only the test results from the Cottrell
Environmental System's second test series (July, 1971)
in which a statistically designed experiment investigated
four variables at two levels, i.e. limestone particle size,
flue gas temperature, coal sulfur and limestone to sulfur
stoichiometry. Other variables such as precipitator
sparking rate and rapping mode were held essentially con-
stant. The four variables have been correlated with corona
power input density which in turn allows estimating the
precipitation rate parameter from Figure 25 with subsequent
sizing of the electrostatic precipitator for any gas vol-
ume and collection efficiency specified. A summary of
pertinent data used for this analysis is contained in
Table XXX. In Figure 25, the precipitation rate and
corona power input data (Table XXX) have been plotted so
as to be able to identify the injected limestone particle
size and flue gas temperature for each point. Note tfhat
the coarse limestone injection generally resulted in
higher precipitation rates at equivalent corona power input,
and the lower gas temperatures allowed increased corona
power input. (As indicated earlier, this latter result
-------
FIGURE 25
PRECIPITATION RATE PARAMETER AS A FUNCTION OF CORONA
POWER DENSITY FOR TESTS WITH LIMESTONE INJECTION
(GAS TEMPERATURE AND LIMESTONE PARTICLE SIZE ARE IDENTIFIED SEPARATELY)
(Data Points From Table XXX)
.
i
c
-;
:
O O
-U d)
'- LO
« \
-U
r: EL,
o
V.(jt
0.53
0.40
0.27
-20-
1 R
i O
1 fi -
'14
in-.
OOS/UIO 1
g o c;
" ? I
C
'V
V
V
^^
X ~
A8
i
°e
1
E
D
-s
/
-s
^
^
^
-^
D
^
A
Lc
3/
Eg. 32
I Ea. 33
O
a
Fine Limestone (High Temp.)
Fine Limestone (Low Temp.)
Coarse Limestone (High Temp.)
Coarse Limestone (Low Temp.)
I
hfi
S3
I
0.1 0.2 0..3 0.4.0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.31.4 1.5 1.6 1.7 1.8
Corona Power Input Density, P (Kilcwatts/1000 Ft2 Collecting Surface)
f\
-------
-93-
can be explained on the basis of lower particulate resis-
tivity at the decreased gas temperature resulting in
higher voltage and corona current input before the preset
spark limitation). Using the simpler form of Equation 22
which is nearly as good a fit as Equation 23, a separate
regression analysis on the coarse and fine limestone test
results was performed involving 7 and 11 sets of data,
respectively.
The following equations were obtained:
(Coarse) W = 0.522 + 0.121 In PA (32)
Correlation Coefficient =0.80
F-Ratio Test Statistic = 16
(Fine) W = 0.46 + 0.136 In PA (33)
Correlation Coefficient =0.81
F-Ratio Test Statistic = 9
Equations 32 and 33 are limited to values of precipitator
corona input power densities in the range of 0.05 to 0.70
kilowatts per 1000 Ft2 of collecting surface. The coarse
and fine limestone particle size distributions from ran-
domly selected tests (Table XXX) are shown in Figure 26.
Separate regression analyses on coarse and fine limestone
injection correlating the corona input power density to the
four process variables tested were performed. (See Table
XXX for data used). From theoretical considerations and
-------
TABLE XXX
SUMMARY OF TEST DATA USED IN CORRELATIONS
(CES Limestone Injection Tests, July 1971)
Test
No.
2
4
6
8
10
11
14
15
17
18
25
26
27
28
29
30
32
33
Flue Gas
Temp . , °F
314
305
301
256
251
290
289
244
243
289
253
289
242
290
241
288
289
241
Limestone
Particle
Size
F(D
F
F
F
C(2>
C
C
C
F
F
C
F
F
F
F
F
C
C
Limestone
Ton/Hr
Feed
7.55
9.50
11.60
11.15
16.75
15.25
14.10
14.45
9.70
9.15
10.55
7.05
6.45
11.15
6.25
5.30
8.50
7.85
Sulfur
Ton/Hr
Fired
1.47
0.99
1.79
1.63
1.08
1.11
1.60
1.39
0.93
1.25
1.25
1.31
1.07
2.04
1.43
1.67
1.85
2.28
Stoichio-
metry.
CaO/S02l ;
1.44
2.69
1.81
1.92
4.34
3.85
2.47
2.91
2.92
2.05
2.36
1.51
1.69
1.53
1.22
0.89
1.29
0.96
Precipitation
Rate
Parameter
FPS
0.24
0.06
0.03
0.35
0.43
0.26
0.33
0.29
0.37
0.17
0.50
0.17
0.26
0.29
0.27
0.18
0.48
0.43
Power
Density
Watts/Ft2
0.093
0.057
0.096
0.460
0.372
0.164
0.139
0.275
0.220
0.112
0.674
0.129
0.296
0.334
0.213
0.199
0.396
0.708
(1) F - Fine (80%-400 Mesh)
(2) C - Coarse (50%-400 Mesh)
(3) Assumes limestone is 100% CaCO3 and all sulfur in the
coal appears in the flue gas as S02
-------
FIGURE 26
W
W ^
Q) 0)
J 4->
0)
H Q
S Q)
rH
>i U
CQ -H
JJ
-P >-l
C rt3
0) O.
o
^ T3
Q) a)
ft -P
05
a) u
>-H
H T3
4J C
(0 M
3
99.9
99.5.
y y . u
98 0-
95 . Cr
90.0-
80.0-
er» fV
o u . (j~
20 . fr
10. a
. 0 -
2.0 J
i n -
0.1-
]
PARTICLE SIZE ANALYSES OF LIMESTONE FEED SAMPLES
-
USED IN SECOND CES TEST SERIES
Fine Limestone
Test No. 6,8,23
24
/
/
.
N
i
^
S&
^
,
V
^
\
p
H
?AH
(**-
ro
/
^
s*^%^
<&£s^
^2
*z$sr
^-~_
xl
Y*
v_
X
£-
^
X
,x.
^^
Coarse Limestone
Test No. 14 ,32,33
m
/
'*
/
^
^
S
7_
'/A
s
' SIEVE
\
I ! '
x*3^
i?
s~
^
"II 1 1
2 4 6 8 10 20 40 60 80100 200 400 600 1C
Particle Diameter (Microns)
-------
-96-
past operational experience, expectations were that the
corona power input would vary directly with the amount
of sulfur in the coal, and inversely with the amount of
limestone injected and the gas temperature (range 240
to about 325 F).
The following equation form was used for the analyses:
c d
y = a + bx, + - + - .,..
* 1 x2 x3 (34)
where,
y = precipitator corona power input
density, P (killowatts/1000 Ft2
f\
collecting surface).
x, = coal sulfur fired, S (tons/hr)
x_ = limestone injected, L (tons/hr)
-2
x., = flue gas temperature, T (°F x 10 )
The resultant equations were:
(Coarse) PA = -1.435 - 0.336S + igi2. + 2i§Z (35>
Correlation Coefficient = 0.96
F-Ratio Test Statistic = 12
(Fine) Pft - -0.990 + .1998 - + L <36>
Correlation Coefficient = 0.83
F-Ratio Test Statistic = 5
Equations 35 and 36 are limited to the following ranges
-------
-97-
representing actual test conditions which are realistic in
practice:
Coal Sulfur Fired (S) 1.0 to 3.2tons/hr
Limestone Feedrate (L) 5.3 to 16.8tons/hr
Flue Gas Temperature (T) (240 to 315)(10~2)°F
Stoichiometry 0.28 (L/S) 1.0 to 4.0
The ratio of limestone feedrate (L) to coal sulfur fired
(S) is a function of Stoichiometry and if the assumption
is made that the limestone is 100% CaCO3 and all the coal
sulfur fired appears in the flue gas as sulfur oxides, the
following relationship is established:
Stoichiometry = 0.28 (37)
By using equations 32, 33, 35, and 36, it is possible to
predict precipitator corona power input and performance
with limestone injection based on the process variables of
limestone size, injection rate, coal sulfur and flue gas
temperature provided the equation limitations indicated
are met.
2. Performance of the Combination
Mechanical-Electrostatic Dust Collector
The dust collecting equipment on Shawnee, Boiler No. 10
(see Figure 2) is a combination multitube mechanical collector
-------
-98-
followed by an electrostatic precipitator. In early years,
when 90% collection efficiency was satisfactory, the eco-
nomics were against combination units. However, demands
for high efficiency changed this, resulting in utilization
of combination unit principles where advantageous, as dis-
cussed below.
Technical advantages cited for the combination unit
are the complementary affects, e.g. mechanical effi-
ciency drops off with lower gas throughput while
precipitator efficiency increases with higher collect-
ing area to volume ratios. Conversely, mechanical
efficiency increases with high throughput while pre-
cipitator performance decreases. Furthermore, grit
collection is more readily done with a mechanical
while fine particulate is more effectively removed
with a precipitator. With a combination unit, elec-
trical failure of the precipitator or other outage
still permits some collection with a mechanical.
Removal of grit particulate ahead of the precipitator
can reduce erosion losses. A multiple tube mechani-
cal preceding the electrostatic in a close couple
will also improve gas distribution as well as reduce
the dust loading allowing the use of a smaller pre-
cipitator.
-------
-99-
Disadvantages of the combination unit are the high
draft loss of the mechanical collector which repre-
sents a higher operating cost (typically, about
0.25 KW per thousand CFM per inch of draft loss),
and also higher capital costs for fans, flues, etc.
With mechanical collectors as primary units, dis-
charge electrode rappers are a necessity and plate
rapping may also be more difficult because of compac-
tion of the finer dust. Abrasion and plugging of
the mechanical tubes can be a consideration.
In the present case where dry limestone is injected into
the boiler for sulfur oxide removal, all the technical ad-
vantages cited above are favored and the use of a combination
collector is desirable, particularly in the case of coarse
limestone.
A. Correlation of Particle Size and
Dust Collector Performance
The most important parameters in determining the performance
of a mechanical collector are dust particle size and speci-
fic gravity. Normally, maximum performance is obtained
when pressure loss across the collector is between 2.5 and
4 inches of water. On the other hand, the electrical
-------
-100-
properties of the dust and level of applied electrical
power are critical parameters in an electrostatic precipi-
tator with particle size of lesser importance.
A critique of particle size as it is related to dust collec-
tor performance on Shawnee Boiler No. 10 follows:
A plot of the particle size analyses contained in Table XIX
through XXII are shown graphically in Figures 26 through 43.
Figure 26 shows particle size distributions of the raw
limestone feed for both the coarse and fine grinds. Note
that the grind was very uniform with the fine having a geo-
metric mean size by weight of about 6 microns and the
coarse 17 microns.
Size distributions for fly ash obtained during no limestone
injection tests (both CES test series) are shown in Figures
27 through 33. Figures 34 through 43 present particle size
distributions of samples taken during the limestone injec-
tion runs (second CES test series).
Using the average distribution curves from the above figures,
fractional efficiency curves were calculated for both the
mechanical and electrostatic collectors. Differences in
-------
FIGURE 27
PARTICLE SIZE ANALYSES OF MECHANICAL COLLECTOR INLET SAMPLES
WITHOUT LIMESTONE INJECTION (TESTS 1A, 1B,3A, 4A, 5A, 5B)
99.9
99.5"
99 .0"
QQ (1 .
y o . v
95.0-
90. 0
en n ,
10.0
5n
U -
.0
1.0
A 1
x^
^r -
-« i
X
r^
X
X
X
^
X
,x
f*
^xO
x^x
X
BAHCO
i r
4
Xl,x
x]
"^?
^.
y
K"
-«
/
X
X
.
jr
_^
^
- si
^x^
x^^
x
Xx
X
EVE
XI
^
X
JT
»_
!
t '
C
r-J
I
4 6 8 10 20
40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 28
C
n
.c
en
VI M
0) (I)
^ 4J
>i O
CO -H
^J
4-J ^
c «3
0) 0,
o
H T5
-H
(0 M
iH
3
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR
INLET SAMPLES WITHOUT LIMESTONE INJECTION (TESTS 3A, 4A, 4B, 5A, 5B)
99. 9
99.5
99.0'
Q D f\ .
y o . u
90.0-
en n .
9w * U
O A A
20 . 0 "
10.0
5.0 -
2.0 '
1.0 '
r> i
'
s
Sss
Y/
V
s
22
//
9
j
f/
kj/
*
^
V
BAHCO
/
TX?
Z
/«
^t
z
^
j^
^
«
^
X"
**
j
^r
x*
^=^
^^
^
- SIEVE
:p-
^
^
I
H
O
4 6 8 10 20
40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 29
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR
OUTLET SAMPLES WITHOUT LIMESTONE INJECTION (TESTS 2A,3A,3B
99.9
a
£ 99.5
on A -i
99.0
" 98 0 -
O Q)
-P 1
H'Q
U
H
>i U
« -H
-P
p ^ 500-
c m ^w.u
OJ £X
o
^ T3 i
CJ 0)
01 t! 20 0-
nj «u . u
0) U
H T3 10.0
-P C
*H 5.0 -
3
3 2.0
1 . 0
n i
Sjt
*<#;
i//
.
^
/>
/
/
3AHCO
-t
/'
S
S*S
&
f i
^
P1
^
^
"^
^
-
'^
j^**^
- SIEVE
f
*^»
>
,4B)
-
.-
I
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 31
PARTICLE SIZE ANALYSES OF MECHANICAL HOPPER SAMPLES WITHOUT LIMESTONE INJECTION
99.9
99.5'
99 . 0
w . 98 0 -
w W o . u
O Q)
^Q! 95.0-
^ 1 C
0>-3 90-°
H Q
QJ 800-
S -H
*J C
^H 5.0 .
U 1 A '
1 . 0
n i
^
(TESTS 1A , IB , 2A , 3A, 3B , 4A, 4B , 5A , 5B)
^
'^*
2
s
?
s
J/fy
*£-
*r
BAHCO
f\ \
sty
&£-
r
*
$
tt
-
^
SI
X'
^
l'
EVE
/jf
v9
>-
1
,
o
>&l
I
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 31
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR
Q o o
sy y
§
99.5"
99.0'
W Q O f\ .
w M 98.0-
o i U
CD -H
4-1
P *-i e;n n
c ro =>u'u
o
M TJ
(1) 0)
Cb -U n n n
Cximulative '
Indica
3 t-i (0 LH M K
. . 0 C
-> o o o
0 C
s
HOPPER SAMPLES WITHOUT LIMESTONE INJECTION
~~7/
//
yr
(TESTS 1A,1B,2A,3A,4A,5A,5B)
///
f
^
$$/
BAH
i
0
s
&
1
#
'
/
%
/
/
/v
/
f
-»
A
?
/
x
'A
/
/
s~s .
22
/
- SIEVK
-
/v
a
X
1 ^.
-
.
6 8 10
20
40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 32
D)
CO M
0) 0)
H Q
& (U
H
>i CJ
CQ-H
-P
C fl3
Q) £X
U
U t3
(U 0)
pt ^j
ro
0) U
> -H
H T)
*J C
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR INLET SAMPLES
WITHOUT. LIMESTONE INJECTION
99.9
99.5
99.0
OP n -
7O U
95.0-
90 . U
80 0 -
50 0
*
O A f\ _
10.0-
5.0 -
. 0
i.o
n i
(TESTS 16,19,20,21,22)
4
/
//
(/x
K-
H^
jr
X
/*
f S
R
^
X
/
"r~.
x
/
'
/
T
X
/
/
//
/ s
ts
s
AHCO
1
>
X
y
X
^
X^
^
.
-**
X
,/
-«
^
s
/
u**
'
^^^^
X
jS/
X
'
xr
- SIEVE
^
I
M
O
I
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 33
in
W t-l
0) 0)
*j -p
0)
H Q
« -H
4J
U H
C nJ
0) cu
U
M t3
G> "H
H T3
-P C
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR HOPPER SAMPLES
WITHOUT LIMESTONE INJECTION (TESTS 16,21,22)
99.9
99.5
99.0'
98.0-
95 . u
90.0-
OU . U -
50.0-
20. fl-
ic. o-
5.0 -
2.0 '
1.0
0.1
y
/&
/v
07
V
^
I
/fo
yf
/
&
^r
t
/
/
Xx^,
BAHCO
1 1
j... |
yi
X
^
?
^
»
X
X1
Ix
^
X*
X"
«,
*^
X*
,*>
(-x^
- SIEVE
!
^2
s^
*-
o
-J
1
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 34
s
w
(U (U
tr-H
H Q
fl)
S i U
« -H
4J
-P M
c fd
o
l-i 13
(1) 0)
pt 4_>
to
(1) U
>-M
U
PARTICLE SIZE ANALYSES MECHANICAL
COLLECTOR INLET SAMPLES
WITH COARSE LIMESTONE INJECTION (TESTS 14,15,32,33)
99.9
99.5'
99 . 0
95.0-
y-. A f\ -1
90 .0
80 0 -
50 0
*
10.0
5.0
. 0
. 0
ft 1
s
//
y/
/
/
'/
/
'
B
S
>
/^
(
^
'
j
-------
n
w n
0) O
>J -u
O
j ) p
G
5 Q)
rH
>i U
« -H
-P
4J >-4
c m
-H
H 73
-u c
(0 M
u
FIGURE 35
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR INLET SAMPLES
WITH COARSE LIMESTONE INJECTION (TESTS 10,11,14,15,25,32,33)
99.9
0.1
C
c
I
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 36
PARTICLE SIZE ANALYSIS OF ELECTROSTATIC PRECIPITATOP OUTLET SAMPLES
O Q O
99 . 9
C
£ 99.5"
99.0-
CO o o n
KJ H 98 . 0
o o
jj o c n
' o U . U -
Jh'o
4J
4-> ^i K n n
D(J . U -
C
23
/
F
i
22
?Z
9
AHCO
/^/
^
/
W^
/^
^
Jd
V
-«
X*
x-'
It
X
xl
X'
-------
FIGURE 37
PARTICLE SIZE ANALYSES OF MECHANICAL COLLECTOR HOPPER SAMPLES
OQ Q t
yy .y
§
S 99.5"
99.0"
W Q o r>
w w yo .u
O <1>
n*J 95.0-
-u e
x« 90.0-
H Q
iii o n n
oU . U -
S Q)
iH
>i U
CQ -H
4J
jj j-i c rt n
c Id 50.0-
U
M T)
o; -H
5 -a 10.0-
4J C
^M 5.0 -
3
§ 2.0 '
1.0
0.1
WITH COARSE LIMESTONE INJECTION (TESTS 14,15,32,33)
S
.<
s
££,
$
r"*'
^£
RAHCO
-
^
<^
E
K
^
/
'#
^
^_5J
.
x^
2
EVE
-/
'
*-
4 6 8 10 20
40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 38
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR HOPPER SAMPLES
WITH COARSE LIMESTONE INJECTION (TESTS 14.15)
no o
yy . y
S
g 99. 51
99.0*
W QQ ft .
Ul M 30 . U
0) 01
^*{ 95.0-
4-) S
giS 9°-°"
-rH Q
OR n n
o u . u H
3 d)
>i 0
ffl -H
u M ^n n~
C
-------
FIGURE 39
I
LI
w
o
iH
>, u
« -H
4J
-P >-l
C (3
(U Cu
O
M T3
0) Q)
H *"O
-P C
n3 M
f»
I
U
PARTICLE SIZE ANALYSES OF MECHANICAL COLLECTOR INLET SAMPLES
99.9
99.5 '
99.0
Q 0 f) .
95.0-
90 . U
80 0 -
50 0 -
? A n .
f-\J . U
10.0
5.0 -
. 0
1.0
n T
WITH FINE LIMESTONE INJECTION (TESTS 2,3,5,6,8)
>
f
>
x^x
s
X
£/x
^
B
/J
//
*
x^
^
^
>^
~j&?2-
s^
r
AHCO.
L
&\
^x
^
c>
^
X
^
s
*?
,**
.^
jS^
r ^^
SIEVE
'\
\"
's
1*
*
UJ
I
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 4Q
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR INLET SAMPLES
WITH FINE LIMESTONE INJECTION (TESTS 2,3,4,5,6,8,17,18,23,24,26,27,28,29,30)
99.9
s
tn
w M
OJ O
-H Q
(U
3 0)
>i U
03 -H
4-1
11 j_j
0) (X
u
(U 0)
0) U
H -a
-P C
3
E
U
6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
FIGURE 41
M
U M
Q) 0)
J -P
(U
11 P
£ 8
CTi-M
rH Q
V
& 0)
rH
>, O
CO -M
4J
4J M
C (0
-rl
H tl
OJ C
a M
u
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR OUTLET SAMPLES
WITH FINE LIMESTONE INJECTION (TESTS 2,3,4,5,6,23,24,26)
99.9
99.5
99.0
98 0 1
95.0-
o A n -i
90 . u
80 0 -
50 0 -
O f\ rt ^
Av »\f
10.0
5.0 -
. 0
. 0
n i
/
.,
/
//
(/ /
7-
f
X
/
/
/
/^
X
/
.
r
/
/
j>
/
X
X
X
X
X
^
^
X
RAHCO 1 *
-^
s
'
s*
» '
X
^
x
1
-------
FIGURE 42
PARTICLE SIZE ANALYSES OF MECHANICAL COLLECTOR HOPPER SAMPLES
99.9
c
10
£ 99.5'
99.0
W QQ ft .
W H S8.U
O i 0 .
CQ -H
4J
+ J^ cn 0 -
c ta DU-U
fli QJ
o
Lj Tl
4) 0)
P^ -P on n-
nj 20.0-
0) O
-H'-O 10.0
-P C
(0 M c rt
rH 5'° '
3
2 .0
1.0 '
n T
WTTH FINE LIMESTONE INJECTION (TESTS 2,3,5,6,8)
.
X
.^
<&
s
I
\
/
3fr
>
^
^^
AHCO
1
'
^X/
/jpr
'jfr
^
df
c_.
,
*i
$
^
/
/,
'
/
/^
'
/ J
/yi
yy^
//
V
SIEVE
77
f
«.
o
I
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
43
n
CO »-l
a) a)
12 0)
rH
>t O
ffl -M
jj Jl
c
Q) O
> -H
H T3
-P C
PARTICLE SIZE ANALYSES OF ELECTROSTATIC PRECIPITATOR HOPPER SAMPLES
WITH FINE LIMESTONE INJECTION (TESTS 17,18,23,24)
99.9
.99.5
99.0
98.0
95.0-
.0
10.0
5.0 n
2.0
1.0
0.1
AHCO
ft
SIEVE
4 6 8 10 20 40 60 80 100 200 400 600 1000
Particle Diameter (Microns)
-------
-118-
size distribution between inlet, outlet, and hopper catch
samples served as a basis for these calculations. The
results for no limestone injection are contained in
Table XXXI and for limestone injection in Tables XXXII
and XXXIII. For comparative purposes, the collector frac-
tional efficiency curves are shown in Figures 44 and 45.
Mechanical collector efficiencies on fly ash alone ranged
from about 25% on the 5 micron size to 90 to 95% on great-
er than 25 microns. However, the electrostatic collector
fractional efficiency was nearly constant, i.e. between
80 and 90% over the entire size range. In general, the
mechanical efficiencies on fly ash plus additive reaction
products is about the same as on fly ash alone or perhaps
a little lower. However, the electrostatic collector
fractional efficiency was about 90% on 5 micron material
and 70% on 25 micron when coarse limestone was injected.
With fine limestone injection, the efficiency varied from
65% on 5 micron to 25% on 25 micron particulate. This
can be logically explained by the fact that, in general,
higher levels of corona power input density were attain-
able with the coarse injection and therefore higher elec-
trical forces were available for holding material on the
precipitator collecting surface.
-------
TABLE XXXI
FRACTIONAL EFFICIENCY OF DUST COLLECTORS - FLY ASH ONLY
(CES Test Series No. 1)
Micron
Size
Interval
0-2
2-4
4-6
6-8
8-10
10-15
15-20
20-25
25-30
>30
MECHANICAL COLLECTOR
FRACTION IN INTERVAL
Inlet
6.5
9.5
7.0
7.0
4.0
10.0
8.0
3.0
5.0
40.0
100.0
Outlet
4. 7
10.7
8.1
5 .5
3.4
3.8
3.4
1 . 1
0.4
1.5
42.6
Hopper
2.0
2 .0
2.6
2 .3
2 .0
4.6
6. 3
4.0
4.0
27.6
57.4
Hopper
$
Outlet
6.7
12.7
10. 7
7.8
5.4
8.4
9. 7
5. 1
4.4
29. 1
100.0
ELECTROSTATIC PRECIPITATOR
FRACTION IN INTERVAL
Inlet
11 .0
25.0
19.0
13.0
8.0
9.0
8.0
2 .0
1.5
3.5
100.0
Outlet
2. 7
3. 5
2.2
1 .4
0. 7
1 . 1
0. 9
0 . 1
0. 3
0. 7
13.6
Hopper
13. 8
25.0
15.5
10.4
5.2
7.8
4. 3
0.9
0.9
2.6
86. 4
Hopper
$
Outlet
16.5
28.5
17. 7
11 .8
5.9
8.9
5. 2
1.0
1 .2
3.3
100.0
PERCENT f
FRACTIONAL EFFICIENCY1 J
Mechanical
Collector
29.9
15. 8
24.4
29.5
37.1
54. 7
65.0
78.4
91 .0
92. 3
Electrostatic
Precipitator
83.6
87. 8
87. 7
88. 3
88.2
87.6
82 . 7
90 .0
75.0
78.8
(1) Hopper (100)
Hopper + Outlet
-------
TABLE XXXII
FRACTIONAL EFFICIENCY OF DUST COLLECTORS - FINE LIMESTONE
Mi cron
Size
Interval
0-2
2-4
4-6
6-8
8-10
10-15
15-20
20-25
25-30
>30
MECHANICAL COLLECTOR
FRACTION IN INTERVAL
Inlet
6.5
13.5
12.0
11.0
9.0
13.0
12 .0
3.0
4.0
16.0
100.0
Outlet
4. 3
8.4
8.0
6.7
3.6
5. 8
4.0
0.9
0.-9
0.9
43.4
Hopper
1 .7
3.1
3.7
2 .8
2 .3
6.2
5 .7
1 . 1
5.0
25.0
56.6
Hopper
&
Outlet
6.0
11.5
11 .7
9.5
5.9
12.0
9.7
1.9
5.9
25.9
100.0
ELECTROSTATIC PRECIPITATOR
FRACTION IN INTERVAL
Inlet
10.0
23.0
18.0
15.0
8.0
11.0
9.0
2.0
2.0
2.0
100.0
Outlet
2 .9
8.6
6.9
4.6
3. 1
3. 8
1.9
1. 3
1.4
3.7
38. 2
Hopper
11. 1
19.2
13.2
6.2
3.1
4.9
2 .2
0. 3
0.5
1 .1
61. 8
Hopper
5
Outlet
16.5
27.8
20.1
10. 8
6.2
8.7
4. 1
1 .6
1 .9
4. 8
100.0
PERCENT
FRACTIONAL EFFICI ENCY ( l J
Mechanical
Collector
28.4
27.0
31 .6
29.5
39.0
51. 7
58. 8
58.0
84.9
96.5
Electrostatic
Precipi tator
79.3
69. 1
65. 7
57.4
50.0
56. 3
53.6
18.8
26. 3
23.0
ro
o
i
(1) Hopper (100)
Hopper + Outlet
-------
TABLE XXXIII
FRACTIONAL EFFICIENCY OF DUST COLLECTORS - COARSE LIMESTONE
(CES Test Series No. 2)
Micron
Size
Interval
0-2
2-4
4-6
6-8
8-10
10-15
15-20
20-25
25-30
>30
MECHANICAL COLLECTOR
FRACTION IN INTERVAL
Inlet
11.0
17.0
11.0
9.0
6.0
11.0
7.0
3.0
5 .0
20. 0
100.0
Outlet
3.4
11.0
10. 3
6.8
4.4
5.3
3.4
0.5
1.5
1.9
48.5
Hopper
1.8
2.8
3.6
2.1
2. 1
4. 1
4.1
1.5
3.1
26.2
51.5
Hopper
§
Outlet
5.2
13.8
13.9
8.9
6.5
9.4
7.5
2.0
4.6
28.1
100.0
ELECTROSTATIC PRECIPITATOR
FRACTION IN INTERVAL
Inlet
7.0
23.0
21.0
14.0
9.0
11 .0
7.0
1.0
3.0
4.0
10.9
Outlet
0.6
2.4
1.9
1 .6
1.0
1 .4
1.0
0.1
0.4
0.5
89. 1
Hopper
14.2
28.4
19.6
9.8
4 .6
8.0
2.7
0. 3
1 .1
0.4
100.0
Hopper
§
Outlet
14.8
30. 8
21.5
11.4
5.6
9.4
3.7
0.4
1.5
0.9
PERCENT
FRACTIONAL EFFICIENCY1 J
Mechanical
Collector
34.6
20. 3
25.9
23.6
32.2
43.5
54.7
75.0
67.5
93. 3
E lect ros t ati c
Precipi tator
95.9
92 . 3
91.3
86. 1
82. 2
88.8
73.0
75.0
73. 3
44 . 4
I
M
to
M
I
(1) Hopper (100)
Hopper + Outlet
-------
100
-122-
Particle Diameter - Microns
-------
100
-123-
90
\
80
A
-P
c
0)
O
H
0)
(X
u
c
a)
H
O
H
-------
-124-
Table XXXIV summarizes the geometric mean sizes and speci-
fic gravities of all particle size analyses on samples from
both Cottrell Environmental Systems test series. The fly
ash at the mechanical inlet for all no limestone injection
tests had an average mean size by weight of about 19 microns
with a range of 12 to 30 microns for individual tests. The
particulate from both the coarse and fine limestone injec-
tion tests had an average mean size of 8.5 to 9.5 microns
regardless of injection rate. The individual tests ranged
between 6 to 13 microns. As stated before, the raw lime-
stone mean particle size ranged from 6 microns for fine to
17 microns for coarse.
The most plausible explanation for the particle size results
obtained at the mechanical collector inlet with limestone
injection is that the boiler, air heater, ductwork, etc.
ahead of the mechanical collector are acting as a primary
mechanical collector, particularly on the very fine and
very coarse material. The fine limestone can plate out on
surfaces by mechanical and thermal diffusion or electro-
static mechanisms while the coarse material is collected
in low velocity ductwork areas and hoppers below the air
heater by gravity, and impaction mechanisms. The overall
effect of these collection mechanisms would be to make the
-------
-' "",=! PF ' 1CI.T S IZ! \N -
c-. -vvpirs F-i'-1" BOTH C:L;S -IES:
(Tron Firurcs 26 to 45)
S amp I e
Point
Limestone
Feeder
Lime stone
Feeder
MC Inlet
ESP Inlet
ESP Outlet
MC Hopper
ESP Hopper
LSP Inlet
USP Hopper
MC Inlet
L S T Inlet
Des cription
Coarse
Fine
Fly Ash
Only
Fly Ash
Only
Fly Ash
Only
Fly Ash
On ly
Fly Ash
On ly
Fly Ash
On ly
Fly Ash
Only
Fly Ash 5 Coarse
Limestone Reaction
Products
Fly Ash f, Coarse
Limestone Reaction
Product s
Test Numbers
14, 32, 33
6, 8, 23, 24
1A§B, 3A,
4A$B, 5A§B
1ASB, 3A,
4A$B, 5A§B
2A, 3A5B, 4B
1A5B,2A,3ASB,
4A&B,5A5B
1A§B, 2A, 3A,
4A, 5A&B
16, 19, 20,
21, 22
16, 21 , 22
14, 15, 32,
33
10, 11, M,
15, 25, 32 ,
33
Average
Geometric
Mean
Size (p)
17
6.0
19
5. 5
4.5
28
4.6
7.0
4.0
8.5
6.0
Speci fie
Gravity
2.55
2.54
2.36
2. 31
1.98
2. 32
2.04
2.53
2. 30
2.69
2.67
Range of
Geometric
Mean Si ze For
Indi vidual
Tests (y)
15 - 20
5-7
12 - 30
5-6.5
3.5 - 5.5
24 - 33
4.2 - 5.2
4.5 - 9
3.8 - 4.3
6.2 - 13
5-7
-------
TA^Li. \X\IV (Continued)
SUMMARY OF PARTICLE SIZL ANALYSES
ON SAMPLES FROM BOTH CES TEST STRHS
(From Figures 26 to 45)
Samp 1 e
Point
ESP Outlet
MC Hopper
HSP Hopper
MC Inlet
IS!1 Inlet
I.SP Our 1 c t
"." i.^-pe r
1 ^ '' i ^ ' i1 L- r
i
i
Description
Fly Ash 6 Coarse
Limestone Reaction
Products
Fly Ash f, Coarse
Limestone Reaction
Products
Fly Ash 5 Coarse
Limestone Reaction
Products
Fly Ash 5 Fine
Limestone Reaction
Pro ducts
Flv Ash f, Fine
Limestone Reaction
Products
Flv -\sh c, Fine
Lirestone Reaction
Products
Fly -\sh 5 fine
i . ^. s -,> ,e Ren .- 1 ion
P re
-------
-127-
particle size distribution at the mechanical collector
inlet more uniform, and less dependent on the size distribu-
tion and amount of injected limestone. Other possibilities
include agglomeration or attachment of fines to larger
particles (fly ash) by impaction, ineffective dispersion
of fines during injection, better calcination on the coarse
material resulting in decreased size by carbon dioxide loss,
and higher utilization of fines in reacting with sulfur
oxides causing an increase in particle size of the reaction
products.
The average particle loading at the mechanical outlet-
precipitator inlet varies with limestone injection rate
(see Figure 46) from about 1.5 grains/SCF with no limestone
addition to about 4.0 grains/SCF with 16 tons/hour lime-
stone feed into the boiler.
-------
FIGURE 46
ELECTROSTATIC PRECIPITATOR PARTICUIATE INLET LOADING AS A FUNCTION OF LIMESTONE FEEDRATE
6.0
5.0-
4.0
3.0
1XJ
00
I
2.a
Q
i.o
Q
O No Limestone
O Fine Limestone
O Coarse Limestone
8 1*0
Limestone Fcedrate, Tons/Hr
12
1*4
16
18
-------
-129-
3. Discussion of Particle Resistivity Data
A. Correlation of In-Situ and Laboratory
Resistivity Measurements
As discussed in an earlier section of the report, a
fundamental parameter in electrostatic precipitation is
the electrical resistivity of the particulate. Many
industrial dusts are poor conductors and as a result
inhibit the performance of precipitators. Generally,
the critical value above which precipitation is dele-
teriously affected is somewhere between 10 and 10
ohm-cm.* ' The gas temperature and moisture content are
the two main factors having the strongest influence on
resistivity. Secondary agents present in some indus-
trial gases, e.g. sulfur trioxide, can drastically
change resistivity. It is this particular agent which
appears to cause the differences in laboratory and in-
situ resistivity of fly ash from coal fired boilers.
(Sulfur trioxide cannot be simulated conveniently in the
laboratory test gas.) Furthermore, the addition of
large amounts of alkali material such as ground limestone
to the boiler flue gas which removes the sulfur trioxide
by chemical reaction is believed to result in degraded
precipitation rates. An objective of the test program
was to measure the effects of limestone injection on
resistivity and precipitation rates.
-------
-130-
In Figure 47, the in-situ reb.istivj.Lic.-5 obt.j im>d lor
coal firing only on full-scale boilers at Shawnc-i- Sta-
tion of TVA and a large midwest utility, and on a pilot
scale combustor at Babcock and Wilcox Company Research
Center are plotted as a function of gas temperature.
Figure 48 displays in-situ resistivities obtained during
limestone injection tests by the same organizations.
The Shawnee data was obtained by Southern Research Insti-
tute*2* (see Table XXXV), K. J. McLean(5) (see Figure 49),
and Cottrell Environmental Systems (see Tables XXIII
through XXV). The midwest utility data was obtained by
Research-Cottrell, Inc.(3* (see Table XXXVI). The pilot
(4)
scale Babcock and Wilcox data for coal firing is
reproduced in Figure 50 and shown for comparison with
full scale data as a dotted line polygon in Figure 47.
Similarly, the Babcock and Wilcox limestone injection
data is reproduced in Figures 51 through 53 and shown as
a dotted line polygon in Figure 48.
Laboratory resistivity measurements obtained on precipi-
tator inlet samples taken during the Cottrell Environ-
mental Systems test series are shown in Figures 54
(without limestone injection) and 55 (with limestone
injection). The in-situ measurements from Figures 47
and 48 are superimposed on this data as solid lined
polygons. Note that although the data is scattered, clue:
-------
FIGURE 47
IN-SITU RESISTIVITIES OBTAINED ON FULL-SCALE & PILOT SCALE PULVKPTZFD
BOILERS WITHOUT LIMESTONE INJECTION
IxlO15
IxlO14
IxlO13-
S
u
1
X
~4
M
S n
w IxlO11
M
U
IxlO11
IxlO9-
1x1 08
^ CES-S1
(Dec.
CES-S1
A (July
CES-S1
B Speci<
(July
dRi K< J>
& Shawn*
SRI-SI
^ (July
B&W-P
TVA C
1969
lawnee
r 1969)
lawnee
, 1971)
lawnee
al Low Sulfur
, 1971)
McLean-
26 (July, 1971
nawnee
, 1971)
ilot Plant
Dais (1967-
Inc. -Midwest
ty (1967)
J
r r^
TL
l^/
i
*
X
X
>
*
o o
X
/
₯S^
'x
X
o
o
o
v__
Encompasses Data From
Figure 49 , Tables XXIII
through XXV, XXXV and
XXXVI
>
X
X
^^^^ <
s
\
>*
4
-^«
Encorrpasses Data
f roir Figure 50 .
v I
^*
^
r~~~
-
.
..
^->
3
i
u
t->
1
300 350 400 450 500 550 600 650
GAS TEMPERATURE (°F)
-------
CJ
i
U
K
FIGURE 48
IN-SITU RESISTIVITIES OBTAINED ON FULL SCALE AND PILOT SCALE PULVERIZED COAL
FIRING BOILERS WITH LIMESTONE INJECTION
1X10
15
IxlO
14
IxlO
13
IxlO11,
ixio9 H
CES-Shawnee
A (July, 1971)
CES-Shawnee
Special Low Sulfur
(July, 1971)
0 K.J. McLean-Shawneg
(July, 1971)
O SRI-Shawnee
(July, 1971)
B&W-Pilot Plant
(1967-1969)
P-, R-C, Inc. Midwest
U Utility, (1967)
IxlO3
Encompasses Data from
Figure 49, Tables XXIII
through XXV, XXXV and
XXXVI
Encompasses Data
fron Figures 51
through 53 .
__ f
-
:
0 50 300 35C 400 450 SCO 550 600 650
GAS TEMPERATURE (°F)
-------
TABLE XXXV
IX-SITU RESISTIVITY DATA OBTAINED BY SOUTHERN RESEARCH INSTITUTE AT
TVA SKAWNEE STATION, BOILER #10 DURING THE CES SECOND TEST SERIES
Da*te
July 15
July 16
July 21
July 27!
Reported
Injection Rate
of CaCOs,
Lb./Min.
333
333
333
167
333
333
Temp. ,
oF
340
255
273
407
360
417
Resistivity, ohm cm, at various electric fields
1.0 KV/cm
...
:::
4.0 x 1011
2.5 KV/cm
:::
5.0 x 1011
5.0 KV/cm
3.0 x 1010
4.0 x 10?}
4. 5 x 10
1. 3 x lo}*
1.1 x 101
(b) Without Limestone Injection
-------
-134-
FIGURE 49
IN-SITU RESISTIVITY DATA OBTAINED BY K.J. McLEAN AT TVA
SHAWNEE STATION, BOILER #10 DURING THE CES SECOND TEST SERIES
I
o
I
B
V
H
EH
H
1
en
CD
Q
1 x 101
1 x 1013-
12 -
1 x 101
o11-
1 x 10
.9
1 x 10
i x in8
T in'
0
00
O Without
Liir.es tone
With Limestone
0 100 200 300 400 500 600
FLUE GAS TEMPERATURE - °F
-------
-135-
TABLi; XXXVI
DATA SUMMARY - FULL SCALE DOLOMITE
INJECTION TEST RESULTS OBTAINED BY
RESEARCH-COTTRELL, INC. AT A LARCH MIDIVEST UTILITY
Parameter
Dolomite Injected-Tph
Coal Fired - Tph
Gas Vol. @ Pptr, ACFM
Gas Temp. @ Pptr. °F
SO? PPM by Volume
SO^ PPM by Volume
Dust Concentrations
(gr/SCFD)
Mechanical Inlet
Precipitator Inlet
Precipitator Outlet
Efficiencies %
Mechanical
Precipitator
Overall
In-Situ Resistivity -
ohm-cm
Precipitation Rate -
FPS
Boiler
Reheat
6
60
492,000
287
1,950
Nil
6.10
1.32
0.60
78.3
55.0
90.2
1 x 1012
0. 15
Superheat
0
65-70
568,000
270
2,550
17
3.70
0.74
0.16
80.0
78.8
95.8
1 x 108
0.34
-------
y
5
i
:_-
H
>
H
: '
EH
Cfl
FIGURE 50
RESISTIVITY OF FLY ASH
SAMPLZS FROM VARIOUS COALS FIRED
IN PILOT PLANT OF B&W
FIGURE 51
10
10
10
10
10
10
10
IN-SITU AND LABORATORY
RESISTIVITIES FOR REACTED ADDITIVE-
FLY ASH SAMPLES FROM B&W PILOT PLANT
)15
)14
)13
)12
r11
,10
.9
-
-
-
-
-
-
?
1 s\
^
p
»
a
#f
0^
^
.A
t*
VAJ
V U
Lah
. In-
I
-
-
>oratqrv
i
i
j
-4
I
-Sit-jl
3
-
I
H
OJ
I
200 300 400 500 600 700
100 200 300 400 500 600
FLUE GAS TEMPERATURE, °F
-------
s
u
EH
H
>
H
EH
W
^
'..
D
Q
FIGURE 52
IN-SITU AND LABORATORY
RESISTIVITIES FOR REACTED ADDITIVE-
FLY ASH MIXTURES FP.OM B&W PILOT PLANT
FIGURE 53
10
io14
io13
io12
TO11
TO10
3
-
^,O . "^/"l
X {/-*
''*» i
:> ; 1
1 /r«
-
r?
i
^
I
i
i
^i
?.-4?;
3 D
-^» e
fa
/H
/
^^
N« H
\
*\
* \
\^ r
S
Lat
- In-
-
joratc
Situ*
-
-
ry
100 200 3i\i «00 500 GOO 700
100 200 300 400 500 600 700
FLIT. GAS TEMPERATURE, °F
-------
1x10
1x10
1x10
)
:~
-
CO
M
w
1x10
FIGURES 4
LABORATORY RESISTIVITY MEASUREMENTS ON PRECIPITftTOR INLET SAMPLES
AS A FUNCTION OF GAS TEMPERATURE WITHOUT LIMESTONE INJECTION
-h
CES-Shawr.ee
(Dec., 1969)
CES-Shavvr.ee
(July, 1971)
CES-Shawnee Low Sulfur
Tests (July, 1971)
Encompasses Data
from Figure 47.
0 50 100 150 200 250 300 350 400 450 500 550 600 650
GAS TEMPERATURE (°F)
-------
IJ
1
>l
H
Lo
H
(/>
-
s
1x10
1x10
1x10
FIGURX 35
LABORATORY RESISTIVITY MEASUREMENTS ON PRECIPITATOR INLET SAMPLES
AS A FUNCTION OF GAS TEMPERATURE WITH LIMESTONE INJECTION
Encompasses Data
from Picture 48.
50 100 150 200 250 300 350 400 450 500
GAS TEMPERATURE (°7)
550 COO 630
-------
-140-
to v.ir idiLions in tj:,h cornpOL. i L j.on, coul '.uifur, rti:.,
there is a general indication that laboratory mouL.un.-
ments are higher than in-situ at a given gas temperature
Of further interest is that at temperatures in the 550
to 650°F range, the resistivities (lab and in-situ) arc
coming closer to coinciding, while at temperatures
below 500°F agreement is poor. This is further evidence
that the flue gas and laboratory test gas are not equi-
valent, and trace constituents in the flue gas are
affecting resistivity due to surface conductivity (most
prevalent at low gas temperatures), but are not critical
at the high temperatures where the bulk resistivity of
the constituents of the ash is controlling.
B. Relationship of Particle Resistivity, Flue Gas
Temperature, and Coal Sulfur (No Limestone Injection)
In general, the higher the percentage sulfur in the coal,
the more sulfur trioxide appearing in the flue gas.
Typically, 1 to 2% of the coal sulfur is converted to
the trioxide. This amounts to about 3 to 6 parts per
million by volume in the flue gas for 0.5% sulfur coal
and six times this amount for 3% sulfur coal, formally,
15 to 25 parts per million at 300°F is sufficient to
condition the dust surface by sulfuric acid condensation
-------
-Ui-
giving resistivities in l!ir> 10 ohin-crti range or lower.
At lower temperatures, less amounts of sulfur trioxide
are required and gas moisture content becomes more impor-
tant. Conversely, at high temperatures, the bulk resis-
tance of the material is controlling, and the coal sulfur
and moisture are not critical. Figure 56 is a plot of
particle resistivity as a function of flue gas tempera-
ture for a range of coal sulfur. The data were taken
from Tables XXIII, XXXV, and XXXVI. The midwest
utilities data are from unpublished Research-Cottrell,
Inc. reports. ' The criticality of coal sulfur
and moisture on particle resistivity are graphically
demonstrated in the lower temperature ranges (varies
five orders of magnitude for 0.5 to 4.0% sulfur),
while at the higher temperatures the effect is nearly
independent of coal sulfur (varies about one order of
magnitude).
C. Relationship of Particle Resistivity, Flue Gas
Temperature, and Coal Sulfur (with Limestone Injection)
Normal expectation with a dry alkaline additive, such as
limestone to the boiler or into flue gas, is a chemical
reaction with the sulfur oxides formed, particularly the
trioxide, resulting in a decreased conditioning effect
-------
2
^
H
>
H
fr
CO
H
in
w
&
w
I
-142-
IN-SITU RrSISTIVI'J'Y VS. TEMPliRATURF. RELATIONSHIP
FOR VARIOUS COAL SUT,FUKS (Tlo Limestone Injection)
mo13-
12
1X10
IxlO11-
10
1x10
« *v *
1x10
IxlO8 -
1x10
OvO.8
\
\
Q. 8 r-%
1.5~
A
/\.8b
'A
3.7
/
/
/
s-9^^
Vly v_^
1.8
\
\
\
\
1.
9
Ao.o
ZX2.7 Q
A 2.4 "2.
A^ 2.2
1°8
^.
/
/
/
MM
t
\
\
; "^--.^
3
^
i
^\jd)0.8
A2-8
A 2. 2
"" "
DATA POINT LEGEND
^^
A3. 2 ^
M»
A CES (Shawnee #10)
O SRI (Shawnee #10)
Q R-C,Inc. (Midwest Utilities)
NOTE: Numbers by data points are
percent sulfur in coal.
200
300 400 500 600
FLUK GAT, TEMPI-RATURi:, °F
700
-------
-143-
and a higher particulate resistivity. Consequently, the
sulfur content of the coal will become relatively inde-
pendent in its affect on resistivity. In Figure 57, the
particulate resistivity is plotted as a function of flue
gas temperature with the coal sulfur indicated for each
data point. The data were taken from tables and reports
as noted above. Of particular interest is the observa-
tion that coal sulfur appears to affect the resistivity
in a random manner. Nevertheless, the data still shows
the affect of low temperature surface conditioning on
resistivity. Apparently, this is due mainly to the mois-
ture in the gas plus a few parts per million of sulfur
trioxide not removed by the limestone. (See Table 4.14
in Reference 4, and Tables 41 and 44 in Reference 2.)
D. Relationship Between Precipitation Rate Parameter
and Particle Resistivity
In establishing the precipitation rate parameter of a
dust, the most critical single parameter is the elec-
trical resistivity. Figure 58 graphically demonstrates
the degradation of the precipitation rate parameter with
resistivity. Two solid line-curves, taken from the
literature,*6' 7* are shown. Data points (Table XXXVII)
from the Shawnee tests, and a large midwest utility, are
plotted for comparison purposes. Verification of the
-------
-144-
FIGURE 57
IN-SJTU RESISTIVITY VS. TEMPERATURE
RELATIONSHIP FOR VARIOUS COAL .SULI'URS
(V?itli Limestone Injection)
l
§
EH
to
H
CO
S
H
1x10
13
1x10
12
1x10
11
1x10
10
1x10'
200.
1.
2. (A
4.0/\ 4
i.eA;/
3.9Qf
1.6$\2.
? Jf\ A
^ ^/ ^ /-
/
f&2.6
.
'
*
O3.1
ZA 2.7
A 3.3
L^^X^
^2.6
^/XV2.7
Z^i:^
7
Al.4
L.SQ
Q3.1
i
^**
0 2-°
'
-
1
''
-
DATA POINT LEGEND
ACES (Sh-awnee HO)
w
O SRI (Shawnee #10)
NOTE: Numbers by data points
are % sulfur in coal
j
300
400
500
600
700
FLUE GAS TEMPERATURE, °F
-------
ORE 58
APPROXIMATE PRECIPITATION RATE PARAMETER VS. RESISTIVITY RELATIONSHIP
WITHOUT AND T7ITH LIMESTONE INJECTION
W
-.
M
a
03
H
(0
o
*J
c
c
H
-u!
fC
-1-1
-H
n.
-H
CJ
O
0.60
0.50
0.40
1x10
10
10" 10" 10'
IN-SITU PARTICULATE RESISTIVITY, OHM-CM
-------
TABLE XXXVII
DATA USED FOR RELATIONSHIP BETWEEN
PRECIPITATION RATE PARAMETER AND PARTICIPATE RESISTIVITY
Source
CES
First Test
Series
Shawnee fflO
December 1969
R-C ,Inc.
Midwest Utility
CES
Second Test
Series
Shawnee #10
July 1971
R-C , Inc.
Midwest Uti lity
Test No.
5A, SB
3B, 4B
9, 16
19, 21
20, 22
6, 14
10, 17
4, 11
8
2, 30
18, 26
23, 24
25, 27
28, 32
29
33
Flue Gas
Temp .
0F
300
298
275
260
326
270
322
261
323
285
316
318
326
271
323
265
260
287
Coal
Sulfur
%
3.22
1.90
1.54
0.85
0.90
3.20
2.66
1.61
1.53
2.59
2.61
2.20
1. 15
1. 87
3. 70
2 . 30
4.04
3.20
In-Situ
Resistivity
ohm-cm
4. 8 x 109
1 1
2. 8 x 10
1.6 x 1012
10
8.4 x 101U
1 1
1. 8 x 10
1.0 x 108
7.3 x 1011
4.5 x 1011
4. 1 x 1011
1.9 x 1011
12
5. 1 X 10
4. 0 x 1011
1 2
3.3 x lO1^
1 2
1. 3 x 10
3.4 x 1012
4. 3 x 1011
9.1 x 1011
1.2 x 1012
Hptn. Rate
Parameter
FPS
0.42
0. 19
0. 26
0.49
0.47
0. 34
0. 18
0.40
0.16
0 .35
0.21
0. 17
0. 14
0. 38
0. 39
0.27
0.43
0.15
Comment
No
Limestone
In j ection
With
Limes tone
Injection
-------
-147-
degradation noted above is indicated. However, the
critical range of resistivity seems to be occurring
between values of 10 and 10 ohm-cm. Obviously, more
specific data are required to quantitatively establish
the relationship between precipitation rate parameter
and resistivity.
4. Discussion of Chemical Analyses Results
All the chemical analyses on particulate samples obtained
during the test program were performed by TVA personnel
at the Chattanooga, Tennessee Laboratory (see Tables
XXVII through XXIX). A summary of the data used in the
following discussion and correlations are contained in
Table XXXVIII.
A. Relationship of Calcium Compounds at Electrostatic
Precipitator inlet with Limestone Feedrate
Since the dust collecting equipment is a combination
mechanical-electrostatic unit, it is of interest to
determine the affect on the dust chemical composition at
the precipitator inlet caused by the mechanical collec-
tor for no, coarse, and fine limestone injection. One
basis for doing this is to correlate the total amount of
-------
TABLE XXXVIII
SUMMARY OF DATA USED IN SECTION ON
CHEMICAL ANALYSES (PPS.147-153)
Test
No.
2
6
8
9
10
11
34
15
18
19
?0
21
22
23
24
25
26
27
28
29
30
32
33
%
MC
Inlet
30.8
33.0
33.3
35.6
36.7
27.7
25.5
CaO
ESP
Inlet
28.6
30.0
31.4
4 .5
23.5
31.6
33.9
34 .7
33.6
1.4
2.2
1.1
5.6
5.9
18.8
26.0
30.8
28.8
3H.6
28.8
27.2
27.7
26.3
±xa txo
CaO/S
ESP Inlet
4.1
4.9
4.4
3.0
3.8
6 .4
6.0
5.3
7.0
3.5
3.7
2.7
7.0
5.4
8. 9
4. 8
6.2
7.4
9.9
7.4
6.5
4.1
4.5
f*aO ZV4-
l^aU /it
ESP Inlet
(Tons/Hr)
0.48
0.64
0.91
0.05
0.43
1.03
1.19
l.OB
0.69
0.04
0.08
0.02
0.13
0.14
0.47
0.80
0.59
0.60
1.12
0.78
0.84
1.11
0.75
(1)
Gas
Temp,
H
H
L
L
L
H
H
L
H
L
H
L
H
H
H
L
H
L
H
L
H
H
L
Precipitation
Rate Parameter
W(FPS)
0.24
O.C3
0.35
0.34
0.43
0.26
0.33
0.29
0.17
0.41
0.58
0.44
0.36
0.13
0.15
0.50
0.17
0.26
0.29
0.27
0.18
0.48
0.43
Tjimp^tont
Feedrate
(tons/hr)
7.55
11.60
11.15
0
16 .75
15.25
14.10
14.45
9.15
0
0
0
0
1.84
3.45
10.55
7.05
6.45
11.15^
6.25
6.30
8.50
7.85
(2).
Type
_Liitie_s tone
F
F
F
-
C
C
C
C
F
-
-
-
-
F
F
C
F
F
F
F
F
C
C
f 3)
Particle l '
Resistivitv
Olvi r*1*!
1 "
1.2X101"
5.6X10-L1
1.6x1^--
i fivi nil
fi.7vi n11
fi.Svi n11
a.gvin11
1 .4v! rii-
5rf >{i .v1
2 .8x1^-""
1 . 8xl011
1.4xlOil
1.8xlOLi
3 . 7x 1 " - -'
2.9xll"l-
1.4x1012 *
2.4xlC:i
1 c; v l r, 1 1
"5.9:.-::1:1
4 .^-:n r1- *
9.0x1.1'^
P.lvlO-11
9.1x10 ' ;
CO
I
(1) H = 290 to 320°F
(1) L = 240 to 260°F
(2) F = 50% by weight less than 6 microns
(2) C = 50% by weight less than 17 microns
(3) In-Situ at Precipitator Inlet
-------
-149-
calcium reported as calcium oxide, as a function of the
amount and particle size of the limestone fed into the
boiler. Using the measured inlet grain loadings and
gas volumes at the precipitator inlet, a rate in tons/hour
of calcium oxide was calculated from the sample analyses.
These were then plotted as a function of limestone feed-
rate in tons/hour in Figure 59. As expected, the amount
of calcium compounds found at the precipitator inlet is
a function of feedrate. Unexpected is the randomness
of the data points with respect to particle size of the
limestone. A regression analysis of Table XXXVIII data
(22 sets) using the form of equation 21, where :
Y = Calcium oxide at precipitator inlet, tons/hour
X = Limestone feedrate to boiler, tons/hour
was performed. The data point from Test 10 was discarded,
since it appears completely alien to the other test data
points and there is no convenient way of determining
whether it is bad or a real point. The following result
was obtained:
Y = 0.12 + 0.071X (38)
Correlation Coefficient =0.91
F - Patio Test Statistic = 99
-------
1.20
en
<
4J
C
H
C
M
0
*J
1.00
o
.
U)
4-
Ci
U
U
C
°-80
0.60-
0.40-
0.20
Figure 59.
CALCIUM OXIDE AT ELECTROSTATIC INLET AS A FUNCTION
OF LIMESTONE FEEDRATE TO THE BOILER
V '
.
X
r '
_0 2
2
»
n
^ Eq. 38
4
6
B
^
3 1
o
X
X
/
D
B
Gas Temp.
Lo Hi
O © No Limestone
Q £} Fine Limestone
i-i Coarse Limestone
0 1
2 1
4 I
D
6
U1
o
I
Limestone Feedrate To Boiler, Tons/Hr
-------
-151-
This equation is limited to limestone feedrates in the
range of 0 to 15 tons/hour.
The conclusions are that the amount of calcium oxide
found at the precipitator inlet is significantly related
to the feedrate in a linear manner, and neither the
particle size of the limestone or the flue gas tempera-
ture at the dust collecting system is significant.
B. Examination of Particle Resistivity at the
Precipitator Inlet as a Function of Calcium Oxide/
Sulfur Ratio for High and Low Temperature Flue Gas
In Figure 60, the in-situ particle resistivity at the
precipitator inlet has been plotted as a function of the
CaO/S ratio in the particulate. The high and low flue
gas temperature ranges are indicated separately. There
appears to be no obvious correlation. However, in
general, the lower gas temperature data seem, on the
average, to result in a lower particle resistivity for
the Svime CaO/S ratio. Nevertheless, it is concluded
that while no significant trends are obvious in Figure
60 relative to resistivity and CaO/S content of the
particulate, this could suggest that under the con-
ditions tested, stoichiometry has little or no effect
on resistivity.
Generally, the bulk chemical composition of the parti-
-------
Figure 60
PARTICLE RESISTIVITY AS A FUNCTION OF THE
CaO/S RATIO AT THE PRECIPITATOR INLET
I
o
H
-P
tfl
H
m
01
H
u
M
(fl
1x10
13
1x10
12
1x10
11
1x10
10
0
0
0 °
o
0
k o
n
o
0 0
O O
o
U o
c
Gas form
O 240-260°F
O 290-320°F
2 4 6 8
Ratio of CaO/S At The Precipitator Inlet
10
-------
-153-
culato and the performance: of t lie pnu: i pi I ill or i-lmlf
correlation. An extensive research program into the
chemical composition and physical nature of the particle
surface is required.
5. Review of Optical Sensor Data
A proprietary Research-Cottrell, Inc. optical sensing
instrument to determine dust concentrations was installed
on the "B" side of Boiler #10 at Shawnee Station (see
Figures 14 and 15). A simplified system diagram is
shown in Figure 61. After standardizing with clean gas
in measuring path and use of slope and intercept controls,
the dust and reference signals are equal and of opposite
polarity under a wide range of light source intensities
when measuring path is clean.
= -EB (39)
With dirty gas, EA decreases with increasing particle
concentration and -Eg remains constant.
Summing amplifier adds signals EA and -EB and multiplies
sum by its gain Gc to provide amplified difference sig-
nal to recorder.
-------
FIGURE 61
SIMPLIFIED SYSTEM DIAGRAM OF THE
RESEARCH-COTTRELL, INC. PROPRIETARY OPTICAL SENSOR
Normal
Dust fO0.9EA
Sensor ^Gain
Test
EA = GA x eA = Dust Signal
Normal
I Dirty Gas Path
I
r£\ Common Light Source
i
i
! Clean Air Path
Zero
Test
-<
Gain
>*v
O Output
5elector
O
Normal
1 Zero
Ref.
Recorder
0 - 10V
EB = GB x eB = Reference Signal
Reference
-------
-155-
Recorder Reading = Gc EA + (-EB) (40)
After an installation has been standardized, the refer-
ence signal -Eg is equal to the maximum difference signal
for that installation. For 0-5 Ringleman calibration,
full scale recorder voltage = (Gc)(-EB). Maximum
summing amplifier output is limited to about 13 volts.
The instrument was operative during the first CES and
second TVA test series. Component failure (signal
amplifier) during the second CES test series aborted
further use of the instrument. Since all TVA tests were
conducted on the "A" side, the correlation of nearly all
the dust loadings with optical readout data are only
qualitative. (Assumes comparable performance of the
"A" and "B" side precipitators.) Table XXXIX summarizes
data taken from the recorder charts during the first CES
test series and the second TVA test series. A plot of
the results (Figure 62) shows a fair correlation between
the recorder chart reading (millivolts) and the precipi-
tator outlet loading (grains/SCF). A critical considera-
tion noted in the use of the optical sensor was the
necessity for cleaning the lenses of the monitor period-
ically (at least daily). This requirement is evidenced
by the two separate curves shown in Figure 62.
-------
-156-
TA1JLE XXXIX
DATA TAKEN FROM THE OPTICAL SENSOR RECORDER CHARTS
Test
No.
1A(CES)
2A
5A
313
413
5B
38 (TVA)
39
40
42
43
44
4G
47
48
50
51
52
54
55
56
58
59
60
61
(.:>
(>]
Gb
G(>
68
69
70
72
73
74
Chart Reading
(Millivolts)
1.8
2.8
2.5
3.7
3.7
2.7
3.1
3.7
3.0
2.9
3.5
4.0
2.8
3.3
3.6
1.9
2.6
3.2
1.1
2.4
2.3
1.6
2.0
2.1
1.2
1.9
1.4
2.4
3.1
1.6
2.2
2.6
2.3
2.9
4.0
ESP Outlet
Loading
(gr/SCF)
0.036
0.321
0.112
0.227
0.328
0.045
0.270
0.416
0.207
0.126
0.263
0.319
0.080
0.313
0.329
0.099
0.146
0.228
0.49
0.362
0.333
0.087
L 0.246
0.278
0.097
0.243
0.094
0.363
0.418
0.211
0.319
0.352
0.129
0.162
0.213
Type
Firing
Coal
r;
Coal + Additive
*
Coal
f
Coal + Additive
\
Coal
Coal + Additive
\
Coal
Coal + Additive
f
Coal
Coal + Additive
|
Coal
Coal + Additive
1
Coal
Coal + Additive
Coal
Coal + Additive
I
Coal
Coal + Additive
t
Coal
Coal + Additive
*
Condition
3f Optical
Sensor
Lenses
Dirtv
Clean
.-
-
»
Dirtv
Lime- (l)
stone
Addition
Rate
0
Y1
V
Medium
Hiqh
0
0
Medium
High
0
Medium
Hiqh
0
Medium
Hiqh
0
Low
Low
0
Low
Low
0
Low
0
Medium
Hiqh
0
Low
Medium
0
Low
Medium
(1)
Low = 1 to 3.5 tons/hour
Medium = 4.5 to 5.5 tons/hour
High = 9 to 10 tons/hour
-------
4.0-i-
i
r^
H
FIGf ? 62
DATA OBTAINED ON PARTICIPATE LOADING
USING AN OPTICAL MONITOR
'B'
r*
c 3.0
B
A
a
L]
O
C
C
CO
c
o
r-!
2.0.
1.0-
A
O
O
C
U O No Limestone
A ^ Lo Limestone
D O Medium Limestone
O O Hi Limestone
Clean
Lens
\.
Di
irty
Lens
I
0.30
0.10
0.20
0.40
Electrostatic Precipitator Outlet Loading, Grain/SCF
("A" side, except where indicated at data point)
-------
-158-
Figure 63 is a typical section of the optical sensor
recorder chart showing various boiler and dust collec-
tor operating modes, e.g. coal firing only, response
when additive is started and stopped, precipitator
rapping puffs, boiler soot blowing, etc. This parti-
cular section of chart covers the time period beginning
about 8:30AM on July 1, 1970 and running continuously
til about 3:00PM on July 3, 1970. During this time
period, TVA was running tests 37 through 44 from their
second test series on the "A" side precipitator. Per-
tinent operating conditions are noted on the chart
(Figure 6"3', pages 159 through 165). As can be seen on
this chart, the optical sensor provides a good qualita-
tive indication of boiler and dust collecting equipment
operation. However, additional refinements and evalua-
tion are necessary for its modification into a quanti-
tative particulate monitoring instrument.
-------
-159-
1 of 7
A .
X -, , ;. :
t!
rzrr:7?~nir"T~ "rirr
IT it 1:
10:/I 3 AM
Peaks are rapping losses
from third section of
precipitator.
FIGURE 63
TYPICAL OPTICAL SENSOR CHART
ON SHAWNEE flO ROLLER
("B" SIDE) WITH AND WITHOUT
LIMESTONE INJECTJ ON
10:40 AM
Chart Speed = 2"/Minute
Boiler Load =143 MW
Coal Ash = 18. 3%
Coal Sulfur =2.7%
Pptr. Eff. = 85.8%
Pptr. Outlet Loading
= 0.27 qr/SCF
8:40 AM (July 1, T'70)
Start - Chart ;-;! 1 "/!'>-.ur
Limestone Fend Rate ''>.'.> Ton--./l:on
(IJOTH: 0 to 10 r.i M i
-------
-160-
2 of 7
3:20 PM
Normal Coal Firing
" "' ' ' ' *
^. -^.v.r;^:^J^ ' - {;!\~^~A
1 ' i 1 -. -- i. ..K
_i 1 ' '''V"-ri»ii=
' "-^-
flffi'': i i I !-N4-~H
' '.., ' !'«'». ' ' : '
Limestone Feed Off
1:20 PM
Boiler Load = 144 MW
Coal Ash = 15.4%
Coal Sulfur =3.0%
Pptr. Eff. = 78.2%
Pptr. Outlet Loading = 0.42 gr/SCF
11:45 AM
Limestone Feed Rate = 10.0 tons/hour
10:45% AM
Chart Speed = l"/hour
Rapping Loss
10:44 AM (July 1, 1970)
2 4
MILLIVOLTS
-------
-161-
£:£3§BB
L.,.-......- L-4- , r_ .. ,_i .*-- -5,
r ' ... ..!_! . T _ =»r-:- -s
.._._.. .,. ^
I *
-
-------
-162-
4 of 7
-I^
-,_ »- TS^. 1--
it- r^j^^^*^ __. ^ i i
10:00 AM
Normal Coal Firing
Boiler Load = 142 MW
Coal Ash = 17.7%
Coal Sulfur =3.4%
Pptr. Eff. = 91.3%
Pptr. Outlet Loading
= 0.13 gr/SCF
6:00 AM
2:00 AM (July 2, 1970)
2 4
MILLIVOLTS
-------
-163-
5 of 7
q:
! -i
14-'
3x"]~3:
-H-r1-! r
jfc
'.
u
U
ii
'<:
7:00 PM
-
- ' - :" i
L'~: ^WT ~ '-'-
_U.
J.I i
"Il^e -^T5?"" ; I ! i~T~ "
Normal Coal Firing
During This Period
Limestone Feed Off
2:40 PM
Boiler Load = 144 MW
Coal Ash = 15.9%
Coal Sulfur =2.7%
Pptr. Eff. = 85.3%
Pptr. Outlet Loading. = 0.32 gr/SCF
Limestone Feed Rate = 9.5 Tons/Hour
12:50 PM
Boiler Load = 143 MW
Coal Ash = 16.1%
Coal Sulfur = 3.0%
Pptr. Eff. = 82.7%
Pptr. Outlet Loading =0.26 gr/SCF
Limestone Feed Rate =4.5 Tons/Hour
10:55 AM (July 2, 1970)
2 4
MILLIVOLTS
-------
-164-
6 of 7
rti
5:00 AM (July 3, 1971)
2 4
MILLIVOLTS
Normal Coal Firing
During This Period
1:00 AM (July 3, 1970)
Normal Coal Firing
During This Period
8:00 PM (July 2, 1970)
-------
-165-
7 of 7
;
i i 1
- -
1
_j-j L
' t
' -4
.-i. ' ; I
^j
2 4
MILLIVOLTS
Boiler Soot Blowing
.
12:00 PM
Normal Coal Firing
During This Period
6:00 AM (July 3, 1970)
-------
-166-
VII. TECHNO-ECONOMIC EVALUATION OF VARIOUS ALTERNATIVES FOR
MAINTAINING THE STACK EMISSION RATE WITH LIMESTONE
INJECTION EQUIVALENT TO A BASELINE CONDITION OF NO LIME-
STONE INJECTION
The baseline conditions for no limestone injection used in
this evaluation were determined by first selecting a coal
having between 2.5 and 3.5% sulfur as being typical of
that burned at the Shawnee Station. Then the boiler and
electrostatic precipitator operating parameters were estab-
lished by averaging test results obtained by the Tennessee
Valley Authority in 1970 when this type of sulfur coal was
fired. (Table XL summarizes these results.) The mechani-
cal collector performance was established by averaging
test results obtained by Cottrell Environmental Systems in
1969. (Table V.) The average baseline conditions obtained
in this manner for Shawnee Station were - (1) a boiler
burning 2.8% sulfur and 15.5% ash coal at a rate of 63.3
tons/hour, resulting in a 141 megawatt load and a flue gas
volume of 570,000 cfm at 309°F having a particulate load-
ing of 3.32 grains/SCF (70°F and 29.9"Hg) at the inlet to
the particulate collection system; (2) a particulate
collection system consisting of a 57.4% efficient cyclone
followed by a 91.3% efficient electrostatic precipitator
(precipitation rate parameter of 0.39 FPS) resulting in
an overall efficiency of 96.3% and a stack emission rate
of 0.122 grains/SCF or 412 pounds/hour.
-------
TABLE XL
SUMMARY OF 1970 TVA TEST RESULTS USED IN ESTABLISHING
BASELINE BOILER AND PARTICULATE COLLECTOR OPERATING
PARAMETERS FOR NO-LIMESTONE INJECTION
(1)
Test
No.
42
46
50
54
58
61
64
68
72
Avg.
ESP Particulate
Loading (gr/scf)
Inlet
1 .446
1.392
1.559
1.465
1.737
1.119
1 .449
1.463
1 .119
1.416
Outlet
0. 126
0.102
0.099
0.149
0.087
0.097
0.094
0.214
0.129
0. 122
ESP
Efficiency
91.3
92.6
93.7
89.8
94.9
91 .6
93.4
85.6
88.5
91.3
Flue Gas
Temp.
C°F.)
316
306
307
310
304
304
310
309
311
309
Gas
Volume ,
(ACFMxlO )
306
295
289
285
279
302
294
287
227
285
(2)
Coal Analysis(%)
Sulfur
3.4
2.7
2.7
2.7
2.8
2.6
3.1
2.5
2.5
2.8
Ash
17.7
17.1
14.0
13.7
14.0
13.8
14.2
14.8
20.2
15.5
Pptn.
Rate
Parameter
(FPS)
0.41
0.43
0.37
0.36
0.46
0.42
0.44
0.31
0.27
0.39
Boiler
Load
(MW)
142
142
142
140
142
141
142
140
139
141
Coal
Firing
Rate
(tons/hr)
64 .0
64.0
64.0
62.5
64.0
63.0
64.0
62.5
62.0
63.3
(1) Tests run with no limestone injection and a precipitator
sparking rate of about 150/min.
(2) Tests with coal sulfur between 2.5 and 3.5%.
-------
-168-
For purposes of this evaluation, an injection stoichiometry
of 2.0 moles of CaO/mole S in the coal was established.
Using the baseline condition of 63.3 tons/hour of 2.8%
sulfur coal, a limestone injection rate of 11.1 tons/hour
was calculated.
Five basic alternatives were considered in the techno-
economic evaluation, i.e. size modification of the presently
installed dust collecting system, use of a "hot" electro-
static precipitator, gas cooling ahead of the dust
collecting system, gas conditioning ahead of the dust
collecting system, and type of electrical energization for
the precipitator.
1. Size Modification of the Presently Installed Dust
Collecting System
Examination of the performance data of the mechanical
collector without and with coarse or fine limestone
injection shows no significant differences, i.e. the
removal efficiency was essentially unaffected, ranging
on the average between 50 and 60% removal. However,
the particulate loading at the mechanical inlet and
outlet will vary with the coal ash content and amount
-------
-169-
of additive injection. The mechanical outlet-electro-
static inlet loading, as a function of limestone feed-
rate, has been shown previously in Figure 46. The
performance of the precipitator is significantly affected
by the particle size of the limestone injected (Table
XXX) with the coarse giving the higher precipitation
rate parameter. Accordingly, the overall efficiency
and the resulting emission rate from the stack will be
a significant function of the electrostatic precipita-
tor performance and inlet particulate loading only. For
purposes of comparing required size modifications for
the baseline no injection, and the coarse or fine lime-
stone injection cases, it has been assumed that the
precipitation rate parameter is unaffected in the 290
to 310°F flue gas temperature range. Using data con-
tained in Figures 19 or 46, and Tables XXX or XL, a
precipitator size modification and cost evaluation has
been made for the presently installed dust collecting
system. Results are summarized in Table XLI.
The estimated precipitator capital cost (installed) of
$5.25/ft2 of collecting plate area includes the base
precipitator flange to flange, support steel, insulation,
foundations, and labor to supervise and install the
precipitator. It does not include the ash handling
-------
-170-
TABLF XI. f
SUMMARY 01' IJLIiCTRO STATIC PR PC 1 P J TATOK SIZI. MOD1I-1 TCA'I IONS
AND COS'IS FOR 1'IIP 1'RI.S1 NTI.Y TNSTM.Ll'H DUST COLLECT I \'G
SYSTLM Rf.QUIRi: 1) TO MAINTAIN A STACK EMISSION RAT I.
EQUIVALENT 10 BASl'.LINi: NO-I.1MCSTO.\T INJECTION
(ESP Follows MC)
Condi 1 1 on
Flue Gas Temperature , °F .
Sulfur Feed Rate, tons/hr^ *
Limestone Feed Rate, tons/hr
Injection Stoichiometry ,
moles CaO/molc S
Gas Volume, ACFM
(21
Pptr. Inlet Loading, gr/cf
@ 70F f, 29.9"Hg
Pptr. Outlet Loading, gr/cf
§ 70F 5 29.9"Hg
Pptr. Efficiency, %
Power Density, KW/1000 ft2 ^
Precipitation Rate, FPS^4'
Precipitator Area1, Ft
Pptr. Sizei'^actor
X Base Size
Pptr. Capital Cost (Installed) ^
$/KW
Baseline No
Limestone
Injection
309
1 .77
0
0
570,000
1 .416
0.122
91.3
0.70
0.39
59,400
1.0
2.21
Conrse
Limestone
Injection
309
1 .77
11 . 1
2
570,000
3.10
0.122
96.1
0. 23
0.36
85,800
1.45
3.21
Fine
Limes tone
Injection
309
1 . 77
11.1
2
570,000
3. 10
0. 122
96.1
0. 15
0.16
193,000
3.25
7.20
(1) Based on 63.3 tons/hr of coal @ 2.8% sulfur.
(2) Taken from Figure 46 or Table XL.
(3) Taken from Figure 19 or Table XXX.
(4) Taken from Table XL or XXX.
(5) Based on a boiler load of 141 megawatts and
prccipitator capital cost (installed) as defined
in the text. ($5.25/ft2 collecting plate area).
-------
-171-
system and any mark-up for profit which can vary widely,
depending upon the vendor.
2. Installation of a "Hot" Precipitator
The use of a straight "hot" precipitator at 600°F (air
heater inlet gas temperature) would eliminate the dust
resistivity problem and, whether limestone is injected
or not, the precipitation rate parameter would be con-
stant, e.g. in the range of 0.3 FPS.
Theoretical considerations show the precipitation
rate parameter is a function of particle size. How-
ever, practical experience has shown that this does
not become important until the size approaches the
submicron range. Therefore the injection of coarse
or fine limestone which had little material in this
range will not affect the precipitation rate parameter
substantially.
Adjusting the baseline gas volume to 600°F and elimi-
nating the mechanical collector (assume 57.4% effic-
ient on fly ash and 55% efficient on fly ash plus
limestone reaction products), the new precipitator
inlet gas volume and particulate loadings would be
788,000 ACFM and 3.32 grains/SCF for no injection,
and 6.88 grains/SCF for 2X stoichiometric injection.
On the basis of the above assumptions, a "hot" pre-
cipitator has been sized and costed that would reduce
.particulate emissions to 0.122 grains/SCF. Results
are surttmarized in Table XLII.
-------
-172-
TABLE XLII
SUMMARY OF THE "HOT" PRECIPITATOR SIZING
AND COSTING FOR SHAWNEE STATION BOILER #10
WITH AND WITHOUT LIMESTONE INJECTION
(Straight Precipitator)
Condition
Flue Gas Temperature, °F.
Sulfur Feed Rate, tons/hr
Limestone Feed Rate, tons/hr
Injection Stoichiometry ,
moles CaO/mole S
Gas Volume, ACFM
Pptr. Inlet Loading, gr/cf
@ 70F § 29.9"Hg
Pptr. Outlet Loading, gr/cf
@ 70F § 29.9"Hg
Precipitator Efficiency, %
Precipitator Rate, FPS
2
Precipitator Area, Ft
Precipitator Capital Cost^
(installed), $/KW
No Limestone
In j ect ion
600
1.77
0
0
788.000
3.32
0.122
96.3
0.30
144.500
5.85
Coarse or Fine
Limestone
Inj ection
600
1 .77
11 .1
2
788.000
6.88
0. 122
98.2
0.30
176.000
7 .10
(1) Based on a boiler load of 141 megawatts and
precipitator capital cost (installed) of
$5.70/ft2 collecting plate area.
-------
-173-
3. Gas Cooling Ahead of the Dust Collecting System
With an alkaline additive injected into the gas stream
which removes most of the sulfur trioxide by chemical
reaction, it is possible to design a dust collecting
system to operate at about 250°F without danger of
corrosion due to sulfuric acid condensation. Since the
present system, normally operates about 300°F, it would
be necessary to cool the gas about 50°F. This could be
accomplished by the addition of more heat transfer sur-
face or possibly by injection of atomized water with
the added benefit of moisture conditioning. Table XLIII
summarizes results of an evaluation using gas cooling
ahead of the dust collecting system.
4. Gas Conditioning Ahead of the Dust Collecting System
The use of conditioning agents, such as sulfur trioxide
(sulfuric acid), to reduce dust resistivity and improve
precipitator performance is well known. However, with
the addition of large amounts of alkali, the condition-
ing affect may be cancelled. Nevertheless, if the
additive surface has been sulfated ahead of the condi-
tioning injection point, it may still be possible to
improve precipitator performance by sulfur trioxide
addition. On this basis, and assuming the precipitation
rate with coarse or fine limestone injection will be
improved to the no limestone level, a size and cost of
a precipitator for limestone injection has been determined.
-------
-174-
TABLH XLIII
SUMMARY OF GAS COOLING AS AN OPTION FOR
COARSE OR FINE LIMESTONE INJECTION
Condition
Flue Gas Temperature, F
Sulfur Feed Rate, Tons/Hour
Limestone Feed Rate, Tons/Hour
Injection Stoichiometry ,
Moles CaO/Mole S
Gas Volume, ACFM
Pptr. Inlet Loading, gr/cf '
@ 70°F 5 29.9"Hg
Pptr. Outlet Loading, gr/cf
@ 70°F 5 29.9"Hg
Precipitator Efficiency, %
Power Density, KW/1000 Ft2
Precipitation Rate, FPS
Precipitation Area, Ft2
Pptr. Capital Cost (Installed) (1^
$/KW
Coarse
Limestone
Inj ection
250
1. 77
11. 1
2
526,000
3.10
0. 122
96. 1
0.51
0.41
69,30*0
2.58
Fine
Limestone
In j ection
250
1. 77
11. 1
2
526,000
3. 10
0. 122
96. 1
0. 30
0.31
92,300
3.44
'Based on a boiler load of 141 megawatts
and precipitator capital cost (installed)
of $5.25/ft2 collecting plate area.
-------
-175-
At 3098F, with a precipitation rate of 0.39 FPS and a
required efficiency of 96.1% for 570,000 ACFM, the
collecting area is 70,000 ft2. The precipitator capital
cost (installed) per kilowatt generated is $2.94.
5. Electrical Energization of the Precipitator
Basically the precipitator electrical system consists
of the electrical load (precipitator), the power con-
version equipment (high voltage power supply), and the
power control equipment (low voltage control). Single
stage industrial gas-cleaning precipitators are
generally energized by H-V direct current which is
derived from commercial alternating current power
supply lines. Power conversion is accomplished in
the H-V power supply by means of A-C voltage trans-
formation and H-V rectification, usually without
ripple filtering. Precipitator energization is con-
trolled by the L-V control which regulates electrical
input to the H-V power supply. The combination of a
H-V power supply and its associated L-V control is
commonly called an electrical set. Most large pre-
cipitators are internally subdivided to provide a
number of isolated electrical sections or collecting
zones. These precipitator subdivisions are made
longitudinally, transversely, or in a longitudinal/
-------
-176-
transverse arrangement in relation to precipitator gas
flow stream. Each section or collecting zone represents
a discrete electrical load requiring an electrical set
for energization.
A single stage precipitator is essentially a gaseous
electrical discharge device which in most cases is
operated at pressures close to atmospheric and tem-
peratures ranging from ambient to several hundred
degrees. As such it has a non-linear voltacre-
current characteristic with discontinuities as illus-
trated in Figure 64. Except for insulator leakage,
negligible current flows until sufficient voltage
exists between the discharge electrode and the
collecting electrode to initiate a corona discharge-
(corona starting voltagej Increasing the voltage
above the corona start point causes precipitator
current to rise sharply until the voltage becomes
sufficiently high to cause random, momentary spark-
over "snaps" between the discharge electrode and the
collecting surface, (sparking region) At this point
the gaseous discharge is highly unstable and can
readily transfer from the sparking mode to the power
arc mode. The power arc mode is characterized by
sustained low voltage and heavy currents which are
limited only by the power supply system impedance.
-------
-177-
FIGURE 64
TYPICAL PRECIPITATOR VOLTAGE VS CURRENT CHARACTERISTIC
c
4) .
H
U
Power Arc
Sparking
Region
Corona
Region
Voltage - KV
-------
-178-
The corona region just prior to and slightly into the
sparking region is the useful portion of the precipi-
tator voltage-current characteristic for particu-
late collection. Fundamental research has shown
that precipitator performance is initially dependent
upon maintaining the highest possible voltage on the
precipitator electrode system. It has also been
shown that some benefits are gained by operation
under controlled sparking conditions again due to
higher operating voltage. Normally the discharge
electrode is operated with negative polarity be-
cause negative corona permits higher voltage op-
eration before sparkover than positive polarity.
Basically the voltage levels required are a function
of the precipitator electrode geometry - including
discharge electrode cross-sectional size and shape
and the discharge wire to collecting surface spacing.
The current flow, at a given voltage, is a function
of the size of the precipitator section - being de-
pendent upon the discharge electrode length and
collecting surface area. In practice, corona voltage
and current levels are further modified by plant
operating conditions such as: type and concentration,
temperature, and pressure; and electrode deposits
and alignment.
-------
-179-
Actual precipitator electrode configurations are
selected to permit stable corona conditions and
relatively high sparking voltages in addition to
practical considerations of durability and economy.
Since sparking voltage is generally governed by the
closest discharge electrode to collecting electrode
spacing, it has been found that electrical section-
alization of a large precipitator permits higher
operating voltages and reduces dust loss due to an
individual sparkover. Differences in particulate
concentration throughout the precipitator also affect
the corona and sparking characteristics. Thus,
sectionalization permits each treating zone to be
energized more closely to ideal levels for the par-
ticular zone.
Back corona is a description term applied to a very
undesirable gaseous discharge phenomena which occurs
in precipitators treating particulate matter having
resistivities greater than ''lO ohm-cm. Under this
condition, a corona discharge occurs on the dust
layer on the collecting electrode as well as the
discharge electrode.
With negative polarity, the typical electrical charac-
teristic of the precipitator is drastically altered by
-------
-180-
back corona. The sparkover voltage for the precipi-
tator is lowered to 50% or less than normal and a
stable heavy-current, low-voltage discharge can occur.
In this latter case, rated current flows at perhaps
30% or less of the voltage normally associated with
the electrode structure. Needless to say, particu-
late collection falls far below design with back
corona because of the low interelectrode voltage.
Normal corona on the discharge electrodes appears
as sharply defined tufts of light which lie along
straight lines, formed by the wires. The back
corona appears as more diffuse tufts of light
randomly spread over the collecting electrode area.
Traditionally, back corona problems have been alle-
viated by: reducing particulate resistivity by process
change; use of conditioning agents; and increased pre-
cipitator sectionalization. It has been found that
back corona conditions can also be solved by con-
trolling the voltage wave shape. This is possible
since a time factor, quite analogous to that of a
capacitor, is involved in the establishment of back
corona. Thus, use of impulse voltages provides
means to raise spark-over and peak operating vol-
tage under back corona conditions.
-------
-181-
Radar type pulse systems which provide sharply
rising voltage pulses have been experimentally
applied and found advantageous in high-resistivity
problem areas. However their commercial applica-
tion has so far been precluded by: general lack
of understanding, economy, apparatus complexity,
and certain electrical component deficiencies.
As previously mentioned, large precipitators are
normally subdivided into discrete electrical sec-
tions. Figure 65 (a) shows typical precipitator
energization arrangements for a sectionalized
precipitator. The Figure 65 (b) arrangement is
often beneficial since gas inlet sections tend to
operate at lower corona power levels (high vol-
tage, low current, heavy sparking) as compared
to gas outlet sections. Half wave energization
does have the disadvantage that dissimilar sec-
tions cannot be properly energized - the energiza-
tion level is limited by the power section. Also
it has been found in certain high-power electrical
set arrangements (50KW or larger sets) that a spark
transient disturbance in one HW section can cause
magnetic circuit unbalance which unduly prolong
the disturbance.
-------
FIGURE 65
TYPICAL PRECIPITATOR ENERGIZATION ARRANGEMENTS
Precipitator
Precipitator
Gas
Inlet
-
-
-
]
1
" " f ~
-
-
-
«
^ if
Gas
Inlet
jX High Voltage Power Supplie.
s^
V
IB
_
^
./
!
i
~*
!
-
_
^
*-
^.
i
M
00
NJ
1
9929
Electrical
1
T
i
i * .
T
T
)<4/j^-Low Voltage Controls . .,
Electrical
T
1
Input Input
Figure 65(a)
All Sections Full-Wave
Figure 65(b)
Half-lVave Inlet Sections
Full-Wave Outlet Sections
-------
-I H 1-
During the present test program, all precipitator
sections were energized full wave. Possible per-
formance .improvement might be achieved by nore
sectionalization, half wave or pulse energization.
Additional testing is required to establish this.
-------
-184-
VIII. RECOMMENDATIONS
Although the use of dry limestone injection into the boiler
hot gases, as a means of significantly reducing sulfur
oxide emissions, appears to be only a stop gap measure use-
ful in existing power plant boilers, the deleterious affects
on electrostatic precipitator performance are analogous to
those experienced when burning low sulfur coals, particularly
the sub-bituminous western coals. In view of this more
general problem, it is recommended that further experimental
work be performed.
1. The present test program has clearly shown the affect of
corona input power density on the precipitation rate para-
meter. The most critical variable that determines corona
power is the particulate resistivity. There are basically
four ways of combating high resistivity, i.e. use of a large
precipitator, use of some form of conditioning such as
moisture, ammonia, sulfur trioxide, etc., control the flue
gas temperature entering the precipitator, or change the
voltage waveform of electrical energization and/or increase
sectionalization. The first three have been the subject of
numerous investigations, however, the latter, although
known to be effective, has never been really investigated
using a carefully planned experimental program. Accordingly,
it is recommended that this be done using fullwave, half-
-------
-185-
wave and pulse energization along with variations in sec-
tional izat ion.
2. The fact that precipitator performance during the special
low sulfur coal tests of this program was as good or better
than when firing the higher sulfur coals points out the
need for establishing additional means other than coal sul-
fur for predicting expected performance. Recent experi-
(14)
mental work by the Bureau of Minesx ' has correlated the
ratio of Nf o + so in tne asn to resistivity. Also, the
of the ash alone appears to be significant.
It is recommended that experimental work relating precipi-
tator performance to coal ash and fly ash chemical con-
stituents be performed.
3. Recent state particulate emission codes are establishing
stack opacity as a means of determining compliance. There-
fore, it is recommended that further work in quantifying an
optical sensor, such as the Research-Cottre11 instrument,
be undertaken.
-------
-186--
BIBLIOGRAPHY
(1) Tennessee Valley Authority, Results Report No. 54,
"Electrostatic Flyash Collector Performance Test,
Shawnee Steam Plant Unit 10", July 9 - August 6, 1969
Tennessee Valley Authority, Results Report No. 62,
"Electrostatic Flyash Collector Performance with Lime-
stone Injection, Shawnee Steam Plant Unit 10", June 9
July 15, 1970.
(2) Southern Research Institute, Final Report to FPA,
Office of Air Programs, Contract CPA70-149, "A Study
of Resistivity and Conditioning of Fly Ash", PP 84-96.
(3) Walker, A. B., "Effects of Desulfurization Dry Addi-
tives on the Design of Coal-Fired Boiler Particulate
Emission Control Systems", paper presented at the 73rd
Annual General Meeting of the CIM, Quebec City,
April 1971.
(4) Attig, R. C. and Sedor, P., "Additive Injection for
Sulfur Dioxide Control - A Pilot Plant Study", B&W
Research Center Report 5960, PHS Contract No. 86-67-127
(5) McLean, Kenneth J., "An Evaluation of the Kevatron
Model 223 Electrostatic Precipitator Analyser",
July, 1971.
(6) White, H. J. "Industrial Electrostatic Precipitation"
Addison Wesley, 1963, LC No. 62-18240.
(7) Sproull, W. T., "Laboratory Performance of a Special
Two-Stage Precipitator for Collecting High Resistivity
Dust and Fume", American Chemical Society, New York,
N. Y., September 1954.
(8) Busby, H. G. T., "Efficiency of Electrostatic Precipi-
tators as Affected by the Properties and Combustion of
Coal", Journal of the Institute of Fuel, May, 1963.
-------
-187-
(9) Lowe, II. J. , et al, "The Precipitation of Difficult
Dusts", Institute of Electrical Engineers, Colloquium
on Electrostatic Precipitators, February, 1965.
(10) Robinson, M. and Brown, R. F., Letter to the Editors,
"Electrically Supported Liquid Columns in High-
Pressure Electrostatic Precipitators", Atmospheric
Environment, Volume 5, PP. 895-896, 1971.
(11) Southern Research Institute, "A Manual of Electrostatic
Precipitator Technology, Part I - Fundementals and
Part II - Application Areas", prepared for the NAPCA
under Contract CPA-22-69-73, August 25, 1970.
(12) Shepard, J. C., "Field Resistivity Measurements at a
Midwest Utility Burning Low Sulfur Coal" (unpublished
Research-Cottrell, Inc. report, August, 1972).
(13) Pfoutz, B. D., "Precipitator Performance and Sulfur
Emission from Pulverized Coal Fired Boilers with
Dolomite Injection" (unpublished Research-Cottrell, Inc,
report, June, 1967).
(14) Selle, S. J., Tufte, P. H., and Gronhovd, G. H., "A
Study of the Electrical Resistivity of Fly Ashes From
Low-Sulfur Western Coals Using Various Methods",
Bureau of Mines, U.S. Department of the Interior,
Grand Forks, N.D., Paper #72-107, 65th Annual Meeting
APCA, Miami Beach, Florida, June, 1972.
-------
188-
TECHNICAL RtPORT DATA
(l'lfn\i' rriiiJ liiilini ii-iii\ tin llu ri'\ CM< In /»/< <
I Id i-nii I at}
KPA-050/2-74r053
t 1 1 ii
Particulate Collection Study, EPA/TVA Full-Scale
Dry Limestone Injection Tests
R.F. Brown
9 PERFORMING OROANI2A1 ION NAME ANO ADDRESS
Cottrell Environmental Systems, Inc.
Division of Research-Cottrell, Inc.
P.O. Box 750, Bound Brook, NJ 08805
3. RLCiriLNrS ACCESSIOIVNO
5 rui'unr DATb
June 1974
G PUirORMING ORGANIZATION CODE
8 PERFORMING ORGANIZATION HfcPORT NCI
9606
10 PRCiGRAM LLEMbNI NO
1AB013: ROAP 21ACY-016
11 CONTRACT/GRANT NO
CPA 22-69-139
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
NERC-RTP, Control Systems Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final; Through 5/73
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16 ABSTRACT
The report evaluates a particulate control system--a mechanical-cyclone/
electrostatic-precipitator (ESP) combination on TVA/Shawnee's full-scale No. 1?
boilerwith and without injecting dry limestone into the boiler for SO2 removal. The
study determined the effects of dry injection and evaluated modification alternatives
(including cost benefits) to maintain particulate emissions with injection equivalent
to baseline particulate emissions (412 Ibs/hr and 570,000 cfm at 309F, with 2. 8%
sulfur and 15. 5% ash coal-firing) without injection. Cyclone performance did not vary
substantially with limestone injection: efficiencies remained about 50-60%. Generally,
ESP performance was adversely affected by dry injection. Cost estimates for size
modification to the currently installed ESP to maintain baseline emission with dry
injection were considered. With coarse limestone, the present ESP at 309F would
have to be increased in size about 45% to maintain baseline emissions. Reducing gas
temperature to about 250F will increase the size only about 17%. With fine limestone,
size increases at 309F and 250F would be 225% and 56%, respectively. For the grass-
roots plant, a cold (250F) ESP appears to be the best option on a cost basis.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
I) IDENTIFIERS/OPEN ENDED TERMS
COSATI I iLlil/Oroup
Air Pollution
Dust Collectors
Limestone
Coal
Combustion
Boilers
Sulfur Oxides
Cost Analysis
Cyclone Separators
Electrostatic Precip-
itators
Sulfur
FlvAsh
Air Pollution Control
Stationary Sources
Dry Limestone Injection
Particulates
13B
13A, 14A
07A
2 ID
2 IB
18. DISTRIBUTION STATEMENT
Unlimited
19 SECURITY CLASS (Ilia Report)
Unclassified
21
NO Ol I'AGES
197
20 SECURITY CLASS (Tins page)
Unclassified
22 PRICE
CPA Form 2220-1 (9-73)
-------
|