fxEPA
United States
Environmental Protection
Agency
Industrial Environmental Research EPA-600/7-79-104a
Laboratory April 1979
Research Triangle Park NIC 27711
Effects of Conditioning
Agents on Emissions from
Coal-fired Boilers:
Test Report No. 1
Interagency
Energy/Environment
R&D Program Report
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
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The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
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This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
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health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
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essary environmental data and control technology. Investigations include analy-
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This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/7-79-104a
April 1979
Effects of Conditioning Agents
on Emissions from Coal-fired Boilers:
Test Report No. 1
by
R.G. Patterson, P. Riersgard, R. Parker, and S. Calvert
Air Pollution Technology, Inc.
4901 Morena Boulevard, Suite 402
San Diego, California 92117
Contract No. 68-02-2628
Program Element No. EHE624A
EPA Project Officer: Leslie E. Sparks
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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ABSTRACT
A field performance test has been conducted on an electro-
static precipitator (ESP) which uses sulfur trioxide as the con-
ditioning agent. The ESP is located at an electric utilities
power plant, burning approximately 1$ sulfur coal.
Tests were conducted with and without injection of the
conditioning agent. The ESP performance was characterized in
terms of particle collection efficiency and the chemical com-
position of particulate and gaseous emissions. Fly ash resis-
tivity and duct opacity were also measured.
Results show an average increase in overall efficiency from
80% to 95% with injection of the conditioning agent. This is
accompanied by a decrease in fly ash resistivity, a decrease in
opacity, and an increase in sulfur trioxide concentration entering
and leaving the precipitator.
111
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CONTENTS
Page
Abstract iii
Figures vi
Tables vii
Acknowledgment iy
Sections
1. Introduction 1
2. Summary and Conclusions
Results 3
Conclusions 5
3. Description of Test
Plant Design 6
Operating Conditions . 9
Test Methods and Schedule 12
4. Test Results
Collection Efficiency 15
ESP Performance Predictions 21
Flue Gas Composition 24
Elemental Analysis 27
Resistivity 32
Opacity 32
Coal Composition 35
5. Economics 38
References 40
IV
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CONTENTS (continued)
Page
Appendices
A. Particulate Sampling Methods 41
B. Particle Size Data 45
C. Particulate Sulfate Data 54
D. Input Data for the ESP Performance Model 56
E. Elemental Analysis Data 58
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FIGURES
Number
Page
1 Plant layout ..................... 7
2 ESP inlet section voltage-current relationships. ... 11
3 ESP outlet section voltage -current relationships ... 11
4 Inlet size distribution for conditioned tests
showing 90% confidence intervals ........... 16
5 Inlet size distribution for baseline tests
showing 90% confidence intervals ........... 17
6 Outlet size distribution for conditioned tests
showing 90% confidence intervals ........... 18
7 Outlet size distribution for baseline tests
showing 90% confidence intervals ........... 19
8 Grade penetration curves for S03 conditioned
tests ......................... 22
9 Grade penetration curves for baseline tests ...... 23
10 Controlled condensation system ............ 26
11 SOa concentration of flue gas at ESP inlet ...... 29
12 Mass concentrations of major elements in fly
ash with S03 conditioning ............... 30
13 Mass concentrations of major elements in fly
ash from baseline test ................ 31
14 In-stack opacity probe ................ 34
15 Opacity in outlet duct ................ 36
Appendix
A-l Modified EPA sampling train with in-stack
cascade impactor ................... 43
VI
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TABLES
Number^ Page
1 Electrostatic Precipitator Design Information .... 8
2 Boiler Load Data 10
3 Summary of Overall Efficiencies 20
4 ESP Inlet Flue Gas Conditions 25
5 ESP Outlet Flue Gas Conditions 25
6 Concentration of S03 in Flue Gas 28
7 Inlet Fly Ash Resistivity 33
8 Chemical Analysis of Coal 37
9 Capital and Operating Costs 39
Appendices
B-l Inlet and Outlet Particle Data for Run 1 46
B-2 Inlet and Outlet Particle Data for Run 2 46
B-3 Inlet and Outlet Particle Data for Run 12 47
B-4 Inlet and Outlet Particle Data for Run 13 47
B-5 Inlet and Outlet Particle Data for Run 14 48
B-6 Inlet and Outlet Particle Data for Run 16 48
B-7 Inlet and Outlet Particle Data for Run 17 49
B-8 Inlet and Outlet Particle Data for Run 21 49
B-9 Inlet and Outlet Particle Data for Run 23 50
B-10 Inlet and Outlet Particle Data for Run 24 50
VII
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TABLES (continued)
Number
B-ll Inlet and Outlet Particle Data for Run 26 51
B-12 Inlet and Outlet Particle Data for Run 28 51
B-13 Inlet and Outlet Particle Data for Blank Run 3. . . 52
B-14 Inlet and Outlet Particle Data for Blank Run 5. . . 52
B-15 Inlet and Outlet Particle Data for Blank Run 10 . . 53
B-16 Inlet and Outlet Particle Data for Blank Run 19 . . 53
C-l Results of Particulate Sulfate Tests 55
D-l Input Data for the ESP Performance Model 57
E-l Minimum Sensitivities of Elements 59
E-2 Results of Elemental Analysis of Fly
Ash on Cascade Impactor Substrates 60
Vlll
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ACKNOWLEDGMENT
A.P.T. wishes to express its appreciation to Dr. H.J. White
who provided valuable consultation, and to Dr. Leslie Sparks,
the EPA Project Officer, for excellent coordination and technical
assistance in support of this test program. The assistance and
coordination provided by plant personnel at the test site also is
sincerely appreciated.
IX
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SECTION 1
INTRODUCTION
The Particulate Technology Branch of the U.S. EPA In-
dustrial Environmental Research Laboratory, Research Triangle
Park, NC has contracted with A.P.T., Inc. to conduct a series
of field test performance evaluations of electrostatic preci-
pitators (ESP) which use flue gas conditioning agents to im-
prove their performance. This report presents the results of
the first field test conducted at an electric utilities power
plant which burns low sulfur coal. Sulfur trioxide injection
is used to condition the flue gas before it enters the electro-
static precipitator.
Flue gas conditioning agents are used primarily for main-
taining high particulate collection efficiency in electrostatic
precipitators operating on high electrical resistivity fly ash
resulting from the combustion of low sulfur coals. Flue gas
conditioning is not usually designed into a new installation
but rather is used as a corrective measure for a precipitator
which is unable to meet emission or opacity standards.
Many potential conditioning agents have been investigated
and a number are available commercially. Conditioning agents
may be injected in the boiler or may be injected downstream
from the air preheater. Their effectiveness will depend to
some extent on the flue gas composition and temperature.
The improved collection efficiency associated with flue
gas conditioning generally is attributed to a decrease in the
fly ash electrical resistivity. However, other mechanisms such
as an increase in space charge and a reduction in rapping re-
entrainment losses may be more important than resistivity in
some situations.
-------
This test program is being conducted to obtain an exten-
sive data base for evaluating the effectiveness of various
conditioning agents. It is planned that each test will provide
sufficient data to identify the important mechanisms in effect
and to quantify any additional process emissions which result
from the use of the conditioning system.
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SECTION 2
SUMMARY AND CONCLUSIONS
A field performance test has been conducted on an ESP which
uses sulfur trioxide injection for flue gas conditioning. The
ESP is located at an electric utilities power plant, burning
approximately 1% sulfur coal.
Tests were conducted with and without injection of the
conditioning agent. The ESP performance was characterized in
terms of overall and grade particle collection efficiency and
the chemical composition of particulate and gaseous emissions.
Fly ash resistivity and in-stack opacity were also measured.
RESULTS
The ESP has a design efficiency of 951 when burning high
sulfur coal. When low sulfur coal is burned, the precipitator
cannot maintain its design efficiency without gas conditioning.
During the unconditioned tests it was observed that sparking
was much more frequent than during the conditioned tests.
The overall and grade collection efficiencies were deter-
mined from particle size and mass data obtained using in-stack
cascade impactors. Overall efficiencies were also obtained
using a modification of EPA Method 5. The overall mass ef-
ficiency when S03 injection was used for gas conditioning
averaged 94.91. Without S03 injection, the average efficiency
decreased to 80.2%. The grade penetration curves showed im-
proved collection for all particle sizes measured (from about
0.3 to 5 ym dia.) when the conditioning agent was used. How-
ever, the improvement appears to be more pronounced for the
larger particle sizes.
The measured overall and grade efficiencies compared well
with the ESP performance model (Sparks, 1978) for conditioned
and baseline tests.
-------
Elemental analyses of certain cascade impactor particulate
samples (outlet only) were conducted for the conditioned and
baseline tests. The conditioned tests showed an increase in
the mass of sulfur leaving the ESP as particulate (2.5 mg/DNm3)
relative to the baseline tests (0.4 mg/DNm3). Mass emissions
of all other elements analyzed were lower in the conditioned
tests than in the baseline tests. This is consistent with the
lower overall penetration measured for the conditioned tests.
In-situ fly ash electrical resistivity was measured using
a point-to-plane probe at the ESP inlet for the baseline and
conditioned tests. The average resistivity for the baseline
case was 1.7 x 1011 ft-cm. When S03 conditioning was used,
the average resistivity decreased to 4.7 x 1010 fi-cm.
The opacity of the flue gas was measured in the outlet
duct of the ESP for the conditioned and baseline tests. The
average opacity was 401 during the conditioned tests and 80%
during the baseline tests.
Sulfur trioxide concentrations were determined at the
ESP inlet and outlet using the controlled condensation method
(Maddelone, 1977). The average S03 concentration during the
conditioned tests was 10.9 ppm at the inlet and 8.1 ppm at
the outlet. Theoretically, from a material balance, 32 ppm
of S03 were injected. The equivalent of approximately 24 ppm
S03 was accounted for on the fly ash. During the baseline
tests the S03 concentration averaged 1.6 ppm at the inlet
and 1.0 ppm at the outlet. The sulfur content of the fly
ash leaving the ESP decreased from 2.5 mg/DNm3 for the con-
ditioned tests to 0.4 mg/DNm3 for the baseline tests.
The S02 concentration in the flue gas varied from about
650 to 800 ppm at the inlet and from about 600 to 700 ppm at
the outlet. The lower concentration at the outlet may have
been caused by in-leakage of air. This hypothesis is consis-
tent with an observed increase in 02 concentration at the
outlet. The unconditioned (baseline) tests showed about 13%
-------
less S02 at the inlet and outlet, however fluctuations in the
sulfur content of the coal are more than enough to account for
the observed change in S02 concentration.
Coal samples were analyzed for the conditioned and base-
line tests. The sulfur content averaged 1.1 wt I during the
conditioned tests and 0.8 wt \ during the baseline tests.
Otherwise, the samples were very similar with about 11 wt %
ash and very low levels of alkali metals (Na, K, Li, Ca).
CONCLUSIONS
The results of this field test clearly indicate that the
S03 flue gas conditioning system successfully increased the
ESP efficiency from about 801 to near the design efficiency
of 95% when low sulfur coal fly ash is being collected. The
mechanism for improvement appears to be, at least in part, a
decrease in fly ash resistivity. This is consistent with the
observation of a higher sparking rate during the baseline
tests.
The grade efficiency curves indicate a more pronounced
improvement in collection of large particles. This could be
the result of a reduction in reentrainment associated with
use of the conditioning agent.
There was no significant change in S02 concentration
associated with use of the S03 conditioning system. Observed
S02 fluctuations could be accounted for by variations in the
sulfur content of the coal. The sulfur content of the fly
ash and the outlet concentration of S03 increased signifi-
cantly when the conditioning agent was injected.
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SECTION 3
DESCRIPTION OF TEST
PLANT DESIGN
The plant has six power generating units and a seventh unit
under construction. Testing was performed on unit No. 3 which
has a boiler rated at 44 megawatts. Unit No. 3 has a maximum
operating capacity of 58 megawatts producing 10,000 kPa (1,450
psi) steam at 540°C (1,005°F). The location of the S03 injection
ports, and inlet and outlet sampling ports is shown in Figure 1.
The ESP, installed downstream from the air preheater
(Ljlingstrom type) , has a design efficiency of 95% when burning
high sulfur coal. It is preceded by a bank of axial entry cy-
clones of undetermined efficiency. The ESP consists of two
sections in series; i.e., an inlet and an outlet section. Each
has a transformer-rectifier (T/R) set which can be electrically
isolated into a right and left subsection. The wire current is
full wave rectified. Design information for the ESP is given in
Table 1.
The configuration of the precipitator can be seen in Figure
1. The flue gas flows through the axial entry cyclones where it
is directed upward past the S03 injection nozzles into a bend
with turning vanes. There is a diverging section immediately
before the ESP. Downstream from the ESP the flue gas converges
and is directed upward and over the top of the precipitator to
the induced draft fan. Turning vanes are provided to improve
flow distribution.
The eight inlet sampling ports are at the upstream edge of
the diverging section before the ESP. The four outlet ports are
located immediately following the bend over the precipitator.
-------
OUTLET
PORTS
FLOW
CYCLONES
Figure 1. Plant lavout.
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TABLE 1. ELECTROSTATIC PRECIPITATOR DESIGN
INFORMATION
Startup date
Design gas flow
Design gas velocity
Design specific
collector area
Design efficiency
Precipitation rate
Overall configuration
Plates
Wires
Electrical
1972
104 actual m3/s (217,000 actual ft3/min)
1.05 m/s (3.4 ft/s)
36 m2 per actual m3/s (182 ft2 per 1000
actual ft3/min)
95%
IV - 0.084 m/s (0.274 ft/s)
G
2 series chambers
3 electrical sections in parallel
per chamber
36 parallel gas passages
37 plates per chamber (cold rolled
steel sheets)
plate height - 9.5 m (31 ft)
plate length each section - 2.7 m
(9 ft) for total length in direction
of flow of 5.5m (18 ft)
plate-to-plate spacing - 0.23 m (9 in.)
total surface area of plates - 3,730 m2
(40,180 ft2)
12 equally spaced wires per gas passage
wire diameter - 2.8 mm (0.11 in.)
wires are hanging type, placed in the
center 16.4 mm (1/4 in.) of the
plate-plate space
2 transformer-rectifier sets which
were electrically insolatable into
6 subsections
maximum power consumption - -50 kW
-------
Fly ash is removed from the wires and plates by vibrators
which operate for about one minute every five minutes. The col-
lected ash falls into hoppers beneath the ESP. The manually acti-
vated ash handling system pulls the ash from the hoppers with
suction from a water ejector nozzle and deposits it in a silo.
The silo is emptied by truck.
The S03 injection system converts hot vaporized S02 and air
into S03 over a vanadium pentoxide (V05) catalyst. It is injected
into the flue gas downstream from the air preheater and cyclone at
490°C (920°F) through five rows of nozzles. The flue gas is ap-
proximately 160°C (320°F) at the injection point. The S02 is
stored in bulk liquid form and consumed at a constant rate of
approximately 46 Ibs/hr at full load of 58 MW. For 100% con-
version of S02 to S03, this corresponds to a maximum addition of
32 ppm of S03 to the flue gas stream.
OPERATING CONDITIONS
The unit was operated at full load for the duration of the
test. It was controlled to produce a constant steam rate. Full
load was limited by the air intake dampers. The maximum design
flow of the ESP was 104 m3/s (217,000 ACFM). The flow during
the test was slightly lower at 102 m3/s (217,000 ACFM). As can
be seen from Table 2, the power output of the plant increased
on January 31. This was caused by chlorination of the conden-
sers; a cleaning operation which makes the condensers more ef-
ficient, thus enabling higher output from the turbines for the
same steam rate.
Voltage current relationships were determined for the ESP
during both the conditioned and baseline test periods (Figures
2 and 3). The normal operating point at both the inlet and out-
let of the ESP was a voltage of 50 kV and a current density of
o
24 nA/cm . The test data were generated by adjusting the primary
voltage manually and recording the resulting primary and secondary
currents. A secondary voltage meter was not available so that
secondary voltage had to be calculated from the power transmitted
that is:
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TABLE 2. BOILER LOAD DATA
Date
Boiler Load
MW
1/25/78
1/26/78
1/27/78
1/31/78
2/1/78
2/5/78
2/6/78
2/7/78
57.5
57.5
57.5
58
58
5
5
58.5
58.4
58.4
10
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6
u
E-
i—<
CO
H
Z
tu
OS
OS
E
o
CO
w
Q
f-
Z
uu
OS
os
u
35
30
25
20
15
10
5
0
D 1/31/78 CONDITIONED
2/7/78 BASELINE
O
0
o
J_
_L
_L
30
35 40 45 50
SECONDARY VOLTAGE, DC kV
55
60
Figure 2. ESP inlet section voltage-current
relat ionships.
30
25
20
15
10
5
0
D 1/31/78 CONDITIONED
A 2/7/78
BASELINE
30 35 40 45 50
SECONDARY VOLTAGE, DC kV
55
60
Figure 3. ESP outlet section voltage-current
relat ionships .
11
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V2 = 0.85 (1)
I2
where Vi § V2 = primary and secondary voltages, V
Ii § I2 = primary and secondary currents, A
0.85 = efficiency assumed for the transformer -
rectifier set
Two factors contribute to the scatter of data on the curves:
1) sparking, particularly during the unconditioned (baseline)
tests, made the meters jump continually so that they were very
difficult to read accurately; 2) the lack of a secondary voltage
meter necessitated calculations which multiplied the errors in-
herent in the meter readings.
The current-voltage relationships for the inlet and outlet
sections of the ESP are shown in Figures 2 and 3,respectively.
The solid lines represent least squares fits to the data. The
inlet section shows a marked shift to the right for the condi-
tioned case compared to the baseline case. This shift implies
a higher operating voltage is possible for a given current when
the conditioning agent is used. This is consistent with the ef-
fect anticipated with a decrease in fly ash resistivity. The
outlet section (Figure 3) does not show any clear trends.
No spark meter was available but the sparking was clearly
increased during the unconditioned case. Sparking persisted to
the lowest secondary voltage.
TEST METHODS AND SCHEDULE
Field tests of the ESP were conducted with and without in-
jection of the flue gas conditioning agent. Variances were ob-
tained from the proper agencies for periods covering the un-
conditioned tests.
The field test spanned the period January 25 to February 7,
1978. Testing of the conditioned case started on January 25 and
ended on February 2. The boiler unit was shut down three days
for boiler tube repairs (January 28, 29, 30) during this time.
12
-------
A three-day deconditioning period allowed the ESP to come to
steady state before the baseline (unconditioned) tests, which
started February 5 and lasted through February 7.
The particulate analyses included size, mass, resistivity
and chemical composition. Size distributions were obtained at
the inlet and the outlet of the ESP with calibrated cascade im-
pactors. A modified EPA Method 5 train was used for total mass
determinations.
The resistivity of the particulate fly ash entering the ESP
was monitored with an in-situ point-to-plane resistivity probe.
Plume opacity in the outlet duct of the ESP was measured using
a modified opacity meter and was recorded on a continuous basis.
Coal samples were obtained daily and analyzed to characterize
the coal composition during the testing period.
Information on the ESP design, maintenance and operation
were obtained from power plant personnel through survey forms
and personal communications. The current-voltage relationships
for each section of the ESP were determined for conditioned and
unconditioned tests. Annual operating and maintenance costs were
obtained for the ESP, flue gas conditioning equipment and chemicals
Samples of particulate matter collected with a cascade im-
pactor at the ESP inlet and outlet were analyzed to determine
the elemental composition as a function of particle size. The
amount of particulate sulfate collected on the impactor substrates
was determined with an acid-base titration using bromophenol blue
as the indicator. Ion excited X-ray emission analysis was used
to determine the elemental composition.
The flue gas velocity and static pressure were measured at
the inlet and outlet using calibrated S-type pitot tubes. The
molecular weight and density of the gas was determined by measur-
ing the gas composition and temperature. The concentration of
water vapor was determined from measurements of the wet and dry
bulb temperature in the stack.
13
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S02 concentrations entering and leaving the ESP were deter-
mined using a Du Pont S02 stack analyzer (model 459). The output
from the S02 analyzer was recorded on a continuous basis during
the field test.
The concentration of S03 entering and leaving the ESP was
determined with the controlled condensation method as described
by Maddelone (1977).
14
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SECTION 4
TEST RESULTS
COLLECTION EFFICIENCY
Overall and fractional collection efficiencies were deter-
mined from particle size and mass data obtained using in-stack
cascade impactors. Overall efficiencies were also obtained
using a modification of EPA Method 5 (M5). The sampling trains
and procedures are presented in Appendix "A".
Particle size distributions at the ESP inlet are presented
in Figures 4 and 5 for the conditioned and baseline tests,res-
pectively. The inlet size distributions were very consistent
with a geometric mass median diameter (MMD) of 8.5 ym* and a
geometric standard deviation of about 4.
The size distributions at the ESP outlet are presented in
Figures 6 and 7 for the conditioned and baseline tests. The out-
let particles were smaller for the conditioned tests (MMD = 2.2
ym, a = 3.7) than for the has el ine tests (MMD = 3.7 ym, a =4.1).
c> &
A summary of the overall efficiencies is presented in Table
3. The modified M5 test results give somewhat higher mass load-
ings than do the impactor results. Inlet run "2-M5" is suspect
because the nozzle tip may have contacted a layer of fly ash on
the bottom of the duct. The average efficiency data show an in-
crease from 80.2% to 94.9% associated with injection of the con-
ditioning agent.
* The convention used in this report is that physical particle diameters
are shown as ym and aerodynamic particle diameters are shown as ymA. The
physical particle diameter is related to the aerodynamic particle diameter
by: d = d (p C')^2
pa p p
where d = aerodynamic particle diameter, ymA; p = particle density, g/cm3
pa p
d = physical particle diameter, ym; C1 = Cunningham slip correction
" factor, dimensionless
15
-------
OS
w
w
a
P-I
PL,
U
i—i
LO
10.0
9.0
8.0
7.0
6.0
5. 0
4.0
3.0
2.0
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0. 2
0.1
II
H-CH
h-CM
H-CH
I-CH
i-CH
1
1
I
l
1 1
II
0.2 0.5 1 2 5 10 20 30 40 50 60 70 80
CUMULATIVE MASS UNDERSIZE, I
Figure 4. Inlet size distribution for conditioned
tests showing 901 confidence intervals.
* Density assumed to be 2.3 g/cm3
16
-------
*
E
Di
w
H
W
i— i
o
PJ
*— J
o
1 — 1
H
Oi
^
i — i
C/}
>-
o:
d,
1U .
9.
8.
7.
6.
5.
4.
3.
2.
1.
0.
0.
0.
0.
0.
0.
0.
0.
0.
u
0
0
0
0
0
0
0
0
0
9
8
7
6
5
4
3
2
1
_ i 1 I i I ill h|OH' '
_
—
~ -
-
•™ ^
K)H
— —
_
K>H
— t-OH —
_
-
-
- —
i-CH
~ —
_
OH
"
ill i i i i i 1 i i
0.2 0.5 1 2 5 10 20 30 40 50 60 70 80
CUMULATIVE MASS UNDERSIZE, %
Figure 5. Inlet size distribution for baseline
tests showing 90% confidence intervals.
* Density assumed to be 2.3 g/cm3
17
-------
W
E-H
W
U
i— (
H
u
i— i
CO
>->
20
10
0.2
I
o
T 1—
hCH
hCM
l-CH
h-CH
I
I
I
I
5 10 20 30 40 50 60 70 80
CUMULATIVE MASS UNDERSIZE, %
Figure 6. Outlet size distribution for conditioned
tests showing 901 confidence intervals.
* Density assumed to be 2.3 g/cm3
18
-------
OS
PJ
Q
W
i—i
H
O,
U
CO
a:
a.
20
10
0.2
j.
_L
_L
J.
5 10 20 30 40 50 60
CUMULATIVE MASS UNDERSIZE, I
70
80
Figure 7. Outlet size distribution for baseline
tests showing 901 confidence intervals
* Density assumed to be 2.3 g/cm3
I
19
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TABLE 3. SUMMARY OF OVERALL EFFICIENCIES
Run #
With S03
1
2
12
13
14
16
1-M5*
2-M5*
Average
Standard
Without S03
17
21
23
24
26
28
3-M5*
Average
Standard
Inlet
Concentration
mg/DNm3
2,535
2,500
2,375
2,605
2,525
3,139
2,289
12,590
Deviation
2,297
2,470
2,483
2,595
2,449
2,154
4,179
Deviation
Outlet
Concentration
mg/DNm3
104.8
105.3
127.9
145.1
136.3
101.4
265.6
208.3
588.3
428.2
503.3
514.1
426.6
510.2
605.5
Overall
Efficiency
%
95.9
95.8
94.6
94.4
94.6
96.8
88.4
98.3
94.9
2.9
74.4
82.7
79.7
80.2
82.6
76.3
85.5
80.2
3.8
* Modified EPA Method 5
20
-------
Grade penetration curves were computed from the simultan-
eous inlet and outlet test data. The computation was based on
a logarithmic spline fit to the cumulative mass concentration
curves obtained from the cascade impactor data (Lawless, 1978).
The results are presented as Figures 8 and 9.
The conditioned tests show considerably lower penetration
(higher efficiency) than the baseline tests. The improvement is
particularly apparent for large particles.
Each day one impactor run was made to collect a particulate
sample for sulfate analysis. The fly ash on the substrate was
analyzed with an acid/base titration using Bromophenol Blue as
the indicator. The results showed the sulfate concentration to
be below the detectable limit of 1 ppm. One exception was the
final filter of the outlet impactor which showed measurable
amounts of SOi; on some runs. However, this may have been an ar-
tifact resulting from condensation of moisture in the probe.
Moisture which collected on the probe wall may have contained
sulfate ions. When the sampling ended, the liquid could have
drained down to the final filter as the probe was being withdrawn,
The final filter was wet after some runs. The detailed table of
results is presented in Appendix "C".
ESP PERFORMANCE PREDICTIONS
Performance of the precipitator was predicted using a cal-
culator program which models ESP performance (Sparks, 1978). The
predicted performance is based on a model developed by Southern
Research Institute (Gooch, 1975). The predicted baseline overall
efficiency of the ESP is 79.9%, which compares with the measured
value of 80.8%. When the resistivity of the fly ash is reduced
to the conditioned level of 4.7 x 1010 fi-cm, the predicted over-
all efficiency is 92.9%. The measured overall efficiency was
94.9%
Grade penetration curves were calculated with the program
and are shown in Figures 8 and 9. These figures show a slightly
higher penetration than the measured values.
21
-------
1.0
o
o
rt
(H
o
t—I
H
W
W
OH
0.1
0.01
I i I
13
I l l I I l
I I I I l I i
0.2
10
PARTICLE DIAMETER, ym
Figure 8. Grade penetration curves for
S03 conditioned tests.
* Density assumed to be 2.3 g/cm3
22
-------
1. 0
*
c
o
u
rt
?-i
M-i
O
h-H
E-
E-
U4
z
PJ
OH
0.1
0.01
0.2
I I I I I I I I
IIIi i l
PREDICTED
NUJN NO.2 8 -
17.
23 N
26 v
21 \
24
1 I I I I I I
10
PARTICLE DIAMETER,
Figure 9- Grade penetration curves for
baseline tests.
* Density assumed to be 2.3 g/cm3
23
-------
The parameters input to the program are derived from data
obtained during the test period. These are shown in Table D-l
in Appendix "D".
FLUE GAS COMPOSITION
The flue gases were sampled with an Orsat analyzer, a Du Pont
S02 analyzer and a controlled condensation sulfate system (CCS) .
The CCS was used to measure the quantity of S03.
Flue gas velocity was determined with calibrated S-type pitot
tubes. The velocity was measured at 48 points over the cross-sec-
tion of the ducts. The velocity varied erratically over the test
period at both inlet and outlet, as shown in Table 4. This may
have been caused by turbulence from the downstream turning vanes.
The concentrations of 02, C02, H20, and S02 are shown in
Tables 4 and 5 for the inlet and outlet. The 02 concentration
is higher at the outlet (Table 5) than the inlet (Table 4). Dis-
crepancies may be attributed to in-leakage of air since the ESP
operates at a negative pressure of 3.2 kPa (13" W.C.). Using the
average 02 concentrations, an in-leakage rate of 7.5% was com-
puted between the inlet and outlet of the ESP. This compares
well with the leakage rate computed by comparing S02 concentrations
The concentrations of S03entering and leaving the ESP was
determined by the controlled condensation system (CCS) as des-
cribed by Maddelone (1977). A schematic of the CCS is shown in
Figure 10. This method is designed to operate at high temperature.
The sampling probe is maintained at a temperature of 315°C (600°F)
and the quartz filter holder is heated by a heating mantle so that
a gas outlet temperature of 290°C (550°F) is maintained. This
temperature is required to ensure that H2SOi»will not condense in
the filter holder. The separation of S03 from S02 is achieved by
cooling the gas stream below the dew point of H2SOi, but above the
H20 dew point, thus preventing interference from SOa. The con-
densed acid was then titrated with 0.2 N NaOH using Bromophenol
Blue as the indicator.
The probe nozzle was turned downstream during the sampling
period to reduce the quantity of large particles reaching the
24
-------
TABLE 4. ESP INLET FLUE GAS CONDITIONS (DAILY AVERAGE)
Date
1/25/78
1/26/78
1/27/78
1/31/78
2/1/78
2/5/78
2/6/78
2/7/78
Date
1/25/78
1/26/78
1/27/78
1/31/78
2/1/78
2/5/78
2/6/78
2/7/78
Flue Gas
Temperature
°C
142
139
145
133
146
135
147
--
TABLE 5. ESP
Flue Gas
Temperature
°C
144
--
145
147
152
146
--
—
Flue Gas Composition,
%02 %C02 %H20
6.1
5.5
6.6
4.4 14.1 4.0
3.9 14.6 4.5
5.0 14.0 5.6
4.5 14.2 4.4
4.7 14.2
OUTLET FLUE GAS CONDITIONS
Flue Gas Composition,
%02 %C02 %H20
2.2
6.2
4.0
4.9
5.3 14.0 5.0
4.8
6.1
6.0 13.0
Vol. /Vol.
S02 ppm
730
710
720
730
840
650
680
670
(DAILY AVERAGE)
Vol. /Vol.
S02 ppm
700
650
660
680
680
600
620
620
Average
Velocity
m/s
5.8
5.2
5.0
5.9
5.5
5.7
5.2
--
Average
Velocity
m/s
8.8
8.9
9.2
9.6
8.7
8.8
8.8
—
-------
QUARTZ LINED HEATED
PROBE
POWER
SUPPLIES
CONSTANT TEMPERATURE
BATH
GRAHAM CONDENSER
QUARTZ FILTER HOLDER WITH
HEATING MANTLE
SILICA
GEL
SAMPLING
TRAIN
ICE CHEST WITH
IMPINGERS
Figure 10. Controlled condensation system.
-------
filter. If the amount of material on the filter is kept small,
the overall recovery of the CCS is better.
The results of the CCS analysis are shown in Table 6. The
concentration of S03 was higher at the inlet in both cases im-
plying that the fly ash is adsorbing S03 in the ESP. For the
conditioned tests, the measured level of S03 was 10.9 ppm at the
inlet. This is less than the 32 ppm calculated from the S02 in-
jection rate. The remaining sulfate may be on the surface of the
fly ash.
S02 entering and leaving the ESP was determined using a Du
Pont S02 stack analyzer (Model 459). The output from the S02
analyzer was recorded on a continuous basis during the field test
period. The S02 analyzer was switched from the ESP inlet to the
outlet at one-hour intervals. The inlet S02 concentration is
plotted for the test period in Figure 11. The conditioned tests
show a reasonably steady concentration of 700 to 770 ppm (at
the inlet). During the baseline tests the S02 concentration was
about 670 ppm. The lower S02 concentration is most likely a re-
sult of the lower sulfur content in the coal during the baseline
tests.
ELEMENTAL ANALYSIS
The elemental composition of the particulates at the ESP out-
let was determined as a function of particle size. The particu-
lates were collected on 1.0 mil Mylar film substrates coated with
Apiezon "L" grease in a cascade impactor. These substrates were
then analyzed for chemical composition with proton induced -ray
fluorescence (Ensor et al., 1968). Mylar substrates coated with
Apiezon "L" grease exhibit a low background of trace elements when
analyzed.
The results of the analysis, as received, are shown in Ap-
pendix "E". Figures 12 and 13 show the flue gas concentration
for the detectable elements with particle size as the parameter.
These figures show that the concentration of particulate sulfur
increased from 0.4 to 2.5 mg/DNm3 when the conditioning agent
was injected.
27
-------
TABLE 6. CONCENTRATION OF S03 IN FLUE GAS
S03 Concentration
With Conditioning Agent,
ppm by vol.
S03 Concentration
Without Conditioning Agent,
ppm by vol.
Run
Number
1
2
3
4
5
Avg.
a
g
Inlet
6.4
14.6
11.6
*
*
10.9
4.1
Outlet
*
5.8
8.0
9.1
9.5
8.1
1.7
Run
Number
1
2
3
4
5
6
7
Avg.
a
g
Inlet
*
4.4
1.6
1.7
*
2.0
1.2
2.2
1.3
Outlet
*
1.1
*
0.7
0.9
1.1
1.0
1.0
0.2
28
-------
1-0
vo
Cu
CL
E-
W
C
U
O
in
1000
900
800
700
600
500
400
300
1
JAN 25 26 27 28 29 30
31 FEB1
DATE
Figure 11. S02 concentration of flue gas at ESP inlet.
-------
6
n
STAGE
CUT DIAMETER
§ 4
I— t
H
<
OS
W 7
U J
o
u
lIlL ll.llll ..L... .Ill I...
Si S K Ca Ti
Al
Fe
Zn
Figure 12. Mass concentrations of major elements
in fly ash with S03 conditioning.
30
-------
U
7
6
en
e
§ 5
DC
I 4
H
OS
H
W
u 3
o
2
1
0
ll,
1
r
1 1
Cl
^^•••^^^HV
—
Ill
STAGE
JT DIAMETER
-32 ymA
-14 ymA
~ 5 . 3 ymA
~2.6 ymA
-1.5 ymA
~0. 75ymA
~0.40ymA
„ iniii,
i
"* 1
-
-
-
1111 — iiiiiii
Al
Si
Ca
Ti
Fe
Zn
Figure 13. Mass concentrations of major elements
in fly ash from baseline test.
31
-------
RESISTIVITY
Dust resistivity is defined as the resistance of the dust
layer to electrical current, measured in ft-cm. The dust re-
sistivity was measured at the outlet with the Southern Research
Institute in-situ point-to-plane resistivity probe (Smith et al. , 1977)
The dust resistivity is determined from,
A V
' = £r (2)
where p = dust resistivity, Q-cm
A = plate surface area, cm
V = voltage, V
t = dust layer thickness, cm
I = current, A
Table 7 shows the results of the dust resistivity measure-
ments during the conditioned and baseline tests. With S03 con-
ditioning, the average resistivity decreased by a factor of four,
from 1.7 x 10nn-cm to 4.7 x 1010n-cm.
The corresponding precipitation rate, W , increased with
6
the conditioning from 0.05 m/s (0.15 ft/s) to 0.08 m/s (0.27
ft/s). Fly ash resistivity and precipitation rate data, from
previous field performance tests predicted precipitation rates
of 0.05 m/s (0.16 ft/s) and 0.09 m/s (0.28 ft/s) for the above
resistivities (White, 1974). The good agreement between ob-
served and predicted values indicates both the representative
nature of this test and the functional relationship that exists
between resistivity and precipitator efficiency.
OPACITY
The opacity in the outlet duct of the ESP was monitored
continuously during the tests with a Lear-Siegler RM4 opacity
meter modified for portable use. A schematic of the probe is
shown in Figure 14.
32
-------
TABLE 7. INLET FLY ASH RESISTIVITY
Temperature Resistivity
Date °C (°F) ^-cm
With conditioning agent
1/26 121 (250) 3.9 x 1010
1/27 132 (270) 7.6 x 1010
1/31 137 (279) 1.5 x 1010
2/1 139 (283) 5.7 X 1010
Without conditioning agent
Average 4.7 x 1010
a 2.6 x 1010
g
2/5 133 (272) 1.5 x 10n
2/5 137 (278) 1.6 x 10n
2/6 136 (277) 2.0 x 10n
2/6 137 (278) 1.3 x 1011
2/7 142 (287) 2.3 x 10n
2/7 142 (288) 1.7 x 10n
Average 1.7 x
B
0.4 x 1011
33
-------
i
i
RETROFLECTOR
FLUE GkS PATH
HANDLE
LEAR SIEGLER
TRANSMISSOMETER
Figure 14. In-stack opacity probe.
-------
During the conditioned test, the opacity was in the range of
401, as shown in Figure 15. The gap during the conditioned test
is from a shutdown of the No. 3 unit. The opacity rose to the
limit of the scale set on the opacity meter after injection of
the conditioning agent was stopped. After switching to a higher
range, the opacity measured approximately 80%.
COAL COMPOSITION
Coal samples were withdrawn from the coal entering the pul-
verizers every two hours to obtain five or six samples per day.
These samples were mixed and a portion taken for analysis. The
size of the coal entering the pulverizers ranged from 1 mm to
3 cm in diameter. Plant analyses of the coal were also made
available and are included in Table 8.
The sulfur concentrations of the samples taken by A.P.T.
show some deviation from plant data. This may be attributable
to different sampling times. The conditioned period shows a
higher level of sulfur. This increased sulfur content would
cause a higher concentration of S02 in the flue gas, as was
observed.
35
-------
cx
o
90
80
70
60
50
40
30
20
10
SO2 TURNED OFF
I
I
JAN 25 26 27 28 29 30
31 FEB 1
DATE
Figure 15. Opacity in outlet duct,
-------
TABLE 8. CHEMICAL ANALYSIS OF COAL
Analyte
Sodium
Potassium
Lithium
Calcium
Magnesium
Sulfur
Sulfur*'
Ash*
Volatile
hydrocarbons*
Fixed carbon*
Heat content*
Sample from
Conditioned Period
_ Dry wt. %
0.013
0.06
0.00019
0.19
0.02
1.09
0.88
10.7
33.5
SOrJoules/kg
(13,OOOBtu/lb)
Sample from
Unconditioned Period
Dry wt. %
0.016
0.06
0.00014
0.18
0.02
0.78
0.85
11.1
33.6
55.7
30rjoules/kg
(13,100Btu/lb)
*Averages of daily data received from the plant
37
-------
SECTION 5
ECONOMICS
The ESP for unit No. 3 was put on line in 1972 at a cost
of $1.4 million. It normally operates at full load capacity
of 58 megawatts. The flue gas conditioning system was in-
stalled two years later. The cost of the S03 system was not
available. The summary of the available cost data shown in
Table 9 is based on dollar values as of the first half of
1977. Maintenance and operating costs for the ESP shown do
not reflect the cost of power to supply the high voltage.
38
-------
TABLE 9. CAPITAL AND OPERATING COSTS
UNIT NO. 3 1977 COSTS
A. Installed capital costs:
ESP, $24 per kW, Total $1,358,000; on-line 1972
Conditioning equipment: Total $ *; on-line 1974
B. Annual operation and maintenance costs (Does not include
electric power or chemical cost):
ESP $57,693
Conditioning equipment $ 2,845
C. Chemical costs:
Conditioning agent, unit cost
$160/ton (with
freight)
$140/ton (freight
not included)
yearly consumption 55,600 kg/year
yearly cost $9,814
D. Average unit costs:
ESP
Gas conditioning
0.159 mills/kW-hr
0.035 mills/kW-hr (including S02 cost)
0.0078 mills/kW-hr (without S02 cost)
* This value not supplied by plant records
39
-------
REFERENCES
Ensor, D. S., T. A. Cahill, and L. E. Sparks, "Elemental Analysis
of Fly Ash from Combustion of a Low Sulfur Coal," APCA
Meeting 1968, Paper No. 75-33.7, June 1975.
Gooch, J. P., J. R. McDonald, S. Oglesby, Jr., "A Mathematical
Model of Electrostatic Precipitation," EPA 650/2075-037
April 1975. '
Lawless, P. A., "Analysis of Cascade Impactor Data for Calculating
Particle Penetration," Research Triangle Institute, EPA Con
tract No. 68-02-2612, Task 36, 1978.
Maddelone, R. et al., "Process Measurement Procedures: Sulfuric
Acid Emissions," February 1977.
Smith, W. B. et al., "Procedures Manual for Electrostatic Precini
tator Evaluation," EPA Contract No. 68-02-2131, Southern
Research Institute, March 1977.
Sparks, L. E. "SR-52 Programmable Calculator Programs for Venturi
Scrubbers and Electro-Static Precipitators " EPA 600/7-78-0?*
March 1978. UZ6
White, H. J. "Resistivity Problems in Electrostatic Precip-
itation," APCA, Vol. 24, No. 4, April 1974.
40
-------
APPENDIX "A"
PARTICULATE SAMPLING METHODS
41
-------
APPENDIX "A". PARTICIPATE SAMPLING METHODS
CASCADE IMPACTOR TEST METHOD
Cascade impactor measurements were taken at the inlet and
outlet of the ESP to determine the collection efficiency as a
function of particle size. Calibrated UW Mk III cascade impactors
were used. A schematic is shown in Figure A-l.
The particle mass entering and leaving the ESP was deter-
mined from the sum of the mass collected on all the stages (in-
cluding the nozzle of the in-situ cascade impactor).
Greased Mylar and Reeve Angel glass fiber substrates were
used. Substrates were baked at 205°C (400°F) for four hours and
desiccated for two hours prior to weighing. To minimize weight
loss and trace element contamination with greased substrates,
Apiezon L grease was used. Blank test runs with twenty minutes
of exposure to the actual flue gas were performed to confirm no
weight gain on Reeve Angel substrates in the presence of S02.
The elemental composition of the fly ash was determined as
a function of particle diameter. Fly ash samples were taken at
the ESP outlet for this purpose daily. Particulate samples were
obtained with a UW Mk III cascade impactor using 1 mil Mylar sub-
strates, coated with Apiezon L grease. The Mylar substrates and
Apiezon L grease were shown to have a low background of trace
elements.
Particulate sulfate entering and leaving the ESP was obtained
from the chemical analysis of the cascade impactor substrates
(Reeve Angel glass fiber substrates). This was done on one inlet
and one outlet run per day, as the same set of substrates could
not be used for both chemical and gravimetric analysis.
The particulate sample was dissolved in C02-free distilled
water and the amount of sulfate present was determined by a ti-
tration with NaOH with Bromophenol Blue as indicator.
42
-------
THERMOMETER
CASCADE
IMPACTOR
IMPINGER TRAIN
STACK
WALL
I
I
|
THERMOMETERS
ICEBATH
ROTAMETER
VACUUM
GAUGE
ORIFICE METER DRY GAS METER
VACUUM
PUMP
SILICA
GEL
DRYER
Figure A-l. Modified EPA sampling train with in-stack cascade impactor.
-------
EPA METHOD 5 MEASUREMENTS
EPA Method 5 measurements were made to determine accurate
overall mass collection efficiencies. The location of the test
ports in the duct were such that a standard Method 5 would re-
quire 48 five-minute samples. The sampling time was reduced
from five minutes to three minutes each to expedite the test.
The molecular weight and gas density were determined with a
standard Orsat analysis, according to EPA Method 3.
500 mg SAMPLE FOR BIOASSAY TESTING
Particulate samples (500 mg) were collected at the ESP
outlet with one sample collected for each test condition (that
is, with and without flue gas conditioning).
During the conditioned test a sample was scooped from
the fly ash pile at the outlet. During the baseline tests
a Method 5 train was used to collect a sample on a filter.
These samples were forwarded to the EPA project officer.
44
-------
APPENDIX "B"
PARTICLE SIZE DATA
45
-------
TABLE B-l. INLET AND OUTLET PARTICLE DATA FOR RUN #1
Taken 1/25/78 at 11:50 am
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
S amp 1 e
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,510
2,240
1,830
1,680
965
391
123
34.9
21.4
d
pc
(ymA)
30.9
13.5
5.24
2.70
1.57
0.89
0.50
d
P
(ym)
20.26
8.80
3.34
1.67
0.92
0.48
0.23
0.0373
OUTLET
M
cum
(mg/DNm3)
105
80.2
72.9
70.0
60.4
31.5
11.7
4.76
2.56
d
pc
(ymA)
22.3
9.77
3.78
1.88
1.13
0.64
0.36
d
p
(ym)
14.6
6.32
2.37
1.12
0.63
0.31
0.14
0.273
TABLE B-2.
INLET AND OUTLET PARTICLE DATA FOR RUN #7
Taken 1/27/78 at 2:40 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,490
2,120
1,570
1,370
655
328
197
59.8
22.8
d
pc
(ymA)
33.5
14.7
5.68
2.93
1.71
0.96
0.55
d
P
(ym)
21.99
9.57
3.63
1.82
1.02
0.52
0.26
0.0351
OUTLET
cum
(mg/DNm3)
105
81.1
71.3
67.4
55.2
30.4
14.8
6.41
3.62
V
(ymA)
23.6
10.3
4.00
1.99
1.20
0.68
0.38
dP
(ym)
15.4
6.70
2.52
1.20
0.68
0.34
0.15
0.359
N: 20°C, 1 atm;
(P
; ymA =
46
P =2.3g/cm3
-------
TABLE B-3.
INLET AND OUTLET PARTICLE DATA FOR RUN #12
Taken 1/31/78 at 1:40 pm
IMPACTOR
STAGE
NUMBER
Precutter
fj Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,380
2,260
1,470
1,050
486
185
70.2
25.1
20.1
d
pc
(umA)
31.2
13.7
5.29
2.72
1.58
0.91
0.47
d
P
(urn)
20.45
8.90
3.37
1.68
0.93
0.49
0.21
0.0399
OUTLET
M
cum
(mg/DNm3)
128
102
83.6
77.7
61.3
40.3
27.0
20.9
20.1
d
pc
(umA)
23. 5
10.3
3.99
1.92
1.18
0.84
0.37
d
p
(pm)
15.38
6.67
2.51
1.15
0.67
0.44
0.14
0.556
TABLE B-4.
INLET AND OUTLET PARTICLE DATA FOR RUN #13
Taken 1/31/78 at 2:25 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,260
2,370
1,620
1,160
557
222
85.6
22.7
7.56
d
PC
(ymA)
31.2
13.7
5.29
2.72
1.59
0.90
0.51
d
P
(vim)
20.45
8.90
3.37
1.68
0.93
0.49
0.23
0.0397
OUTLET
M
mcum
(mg/DNm3)
145
123
106
93.9
70.3
40.5
20.3
9.39
5.16
d
PC
(ymA)
23.7
10.4
4.02
2.00
1.21
0.68
0.38
d
P
(um)
15.3
6.74
2.53
1.20
0.68
0.34
0.15
0.543
N: 20°C, 1 atm;dpa = dp (pp
^; ymA
47
; p = 2.3 g/cm3
p
-------
TABLE B-5.
INLET AND OUTLET PARTICLE DATA FOR RUN #14
Taken 1/31/78 at 4:20 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
S amp 1 e
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,530
2,400
1,610
1,280
429
195
87.7
37.6
10.0
d
pc
(ymA)
31.4
13.8
5.32
2.74
1.59
0.91
0.47
d
P
(vim)
20.59
8.96
3.39
1.68
0.93
0.49
0.21
0.0399
OUTLET
M
cum
(mg/DNm3)
136
112
102
96.5
82.7
55.3
40.4
33.9
32.0
d
pc
(ymA)
23.5
10.3
3.98
1.92
1.17
0.84
0.37
d
p
(ym)
15.38
6.67
2.51
1.15
0.67
0.44
0.14
0.369
TABLE B-6.
INLET AND OUTLET PARTICLE DATA FOR RUN #16
Taken 2/1/78 at 4:10 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
3,150
2,780
1,910
1,600
713
287
69.6
13.9
8. 36
V
(ymA)
33.1
14.5
5.62
2.89
1.69
0.95
0.54
d
P
(ym)
21.73
9.45
3.59
1.79
1.00
0.52
0.25
0.0359
OUTLET
M
cum
(mg/DNm3)
101
79.2
73.7
72.2
50.5
24.0
8.78
2.87
1.08
t
d
pc
(ymA)
22.0
9.63
3.72
1.85
1.12
0.63
0.35
d
p
(ym)
14.37
6.23
2.33
1.10
0.63
0.31
0.13
0.558
N: 20°C, 1 atm;
(p C')55; ymA=ym(g/cm3)!s; p = 2.3g/cm3
48
-------
TABLE B-7.
INLET AND OUTLET PARTICLE DATA FOR RUN #17
Taken 2/5/78 at 8:15 am
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
S amp 1 e
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,280
2,110
1,550
1,180
774
393
155
49.5
6.19
d
pc
(ymA)
35.3
15.4
5.98
3.08
1.78
1.03
0.53
d
P
(ym)
23.1
10.1
3.83
1.92
1.06
0.57
0.24
0.0323
OUTLET
M
cum
(mg/DNm3)
588
398
365
344
208
84.0
26.0
7.59
4.34
d
pc
(ymA)
23.6
10.3
4.00
1.93
1.18
0.84
0.37
H
p
(ym)
15.4
6.70
2.52
1.16
0.67
0.44
0.14
0.369
TABLE B-8.
INLET AND OUTLET PARTICLE DATA FOR RUN #21
Taken 2/5/78 at 2:30 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,440
2,180
1,490
1,360
675
296
104
32.0
2.67
dpc
(ymA)
32.6
14.3
5.53
2.85
1.65
0.95
0.49
dP
(ym)
21.4
9.31
3.53
1.77
0.98
0.52
0.22
0.0375
OUTLET
cum
(mg/DNm3)
428
290
253
214
136
67.9
25.2
8.85
7.87
V
(ymA)
23.7
10.4
4.01
1.93
1.18
0.84
0.37
dP
(ym)
15.98
6.72
2.53
1.16
0.67
0.44
0.14
0.305
N: 20°C, 1 atm;
^ ; ymA = ym(g/cm3)!s; p = 2.3 g/cm3
49
-------
TABLE B-9.
INLET AND OUTLET PARTICLE DATA FOR RUN #23
Taken 2/5/78 at 4:45 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
S amp 1 e
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,550
2,340
1,720
1,580
811
339
144
16.9
2.82
d
pc
(ymA)
33.6
14.7
5.69
2.93
1.70
0.98
0.51
d
P
(ym)
22.0
9.58
3.64
1.82
1.01
0.54
0.23
0.0354
OUTLET
M
cum
(mg/DNm3)
503
365
348
336
203
117
59.0
32.6
27.4
d
P
(ymA)
23.6
10.3
3.99
1.92
1.18
0.84
0.37
d
P
(ym)
15.41
6.69
2.51
1.15
0.67
0.44
0.14
0.307
TABLE B-10.
INLET AND OUTLET PARTICLE DATA FOR RUN #24
Taken 2/6/78 at 1:10 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
cum
(mg/DNm3)
2,570
2,200
1,570
1,270
658
379
196
32.2
7.43
d
pc
(ymA)
31.9
14.0
5.40
2.78
1.62
0.92
0.52
d
P
(ym)
20.9
9.09
3.44
1.72
0.96
0.50
0.24
0.0404
OUTLET
M
cum
(mg/DNm3)
514
403
360
304
282
178
128
109
104
d
pc
(ymA)
22.7
9.93
3.84
1.91
1.15
0.65
0.36
d
P
(ym)
14.83
6.43
2.41
1.14
0.65
0.32
0.14
0.334
N: 20°C, 1 atm; d = dp (PpC')% ; ymA= ym(g/cm3)Js; pp= 2.3 g/cm3
50
-------
TABLE B-ll
INLET AND OUTLET PARTICLE DATA FOR RUN #26
Taken 2/6/78 at 4:00 pm
IMP ACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
S amp 1 e
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,470
2,270
1,600
1,400
597
173
51. 7
18.1
7.75
d
pc
(ymA)
32.4
14.2
5.50
2.83
1.65
0.93
0.53
d
P
(ym)
21.3
9.25
3.51
1.75
0.98
0.51
0.24
0.0387
OUTLET
M
cum
(mg/DNm3)
427
356
272
259
141
91.5
34.5
11.7
7.91
d
pc
(pmA)
23.2
10.2
3.94
1.96
1.18
0.66
0.38
d
P
(urn)
15.21
6.59
2.48
1.18
0.67
0.33
0.15
0.316
TABLE B-12,
INLET AND OUTLET PARTICLE DATA FOR RUN #28
Taken 2/6/78 at 6:10 pm
IMPACTOR
STAGE
NUMBER
Precutter
§ Nozzle
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
M
cum
(mg/DNm3)
2,150
1,940
1,330
926
483
212
66.5
15.3
12.8
d
pc
(ymA)
32.3
14.1
5.47
2.82
1.64
0.93
0.53
d
P
(ym)
21.2
9.21
3.49
1.75
0.97
0.51
0.24
i
0.0391
OUTLET
M
cum
(mg/DNm3)
510
354
312
301
174
87.9
33.4
10.8
8.20
d
pc
(ymA)
22.7
10.4
4. 01
2.00
1.20
0.68
0.38
d
P
(ym)
14.82
6.72
2.53
1.20
0.68
0.34
0.15
0.305
N: 20°C, 1 atm; dna = dn (pn C ' )
pa p p
ymA = ym(g/cm3 ) \ P = 2 . 3 g/cm
51
-------
TABLE B-13.
INLET AND OUTLET PARTICLE DATA FOR BLANK RUN #3
Taken 1/25/78 at 3:45 pm
IMPACTOR
STAGE
NUMBER
Probe
Pre-filter
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
Loading
mg
17.6
151.0
-0.1
-0.3
-0.4
-0.3
-0.3
-0.6
-0.3
-0.4
V
(ymA)
26.8
11.8
4.45
2.28
1.29
0.72
0.42
0.051
OUTLET
Loading
mg
7.7
41.0
0.0
-0.1
-0.3
-0.1
-0.3
-0.2
-0.3
0.0
d
pc
(ymA)
21.3
9.3
3.49
1.82
1.02
0.57
0.33
0.349
TABLE B-14.
INLET AND OUTLET PARTICLE DATA FOR BLANK RUN #5
Taken 1/27/78 at 9:10 am
IMPACTOR
STAGE
NUMBER
Probe
Pre-filter
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
Loading
mg
8.9
105.6
0.0
-2.0
-0.1
-0.1
0.0
-0.2
0.0
0.0
V
(ymA)
28.9
12.7
4.80
2.47
1.39
0.78
0.45
0.044
OUTLET
Loading
mg
13.0
29.6
0.0
-0.2
-0.2
0.0
0.0
-0.1
0.0
35.9
V
(ymA)
20.6
9.1
3.4
1.8
0.99
0.55
0.32
0.410
N: 20°C, 1 atm; d
dp (pp
52
Pp=2.3g/cm3
-------
TABLE B-15.
INLET AND OUTLET PARTICLE DATA FOR BLANK RUN #10
Taken 1/31/78 at 8:25 am
IMPACTOR
STAGE
NUMBER
Probe
Pre-filter
1
2
3
4
5
6
7
Filter
Sample
Volume
(DNm3)
INLET
Loading
mg
5.2
160.1
0.1
-0.1
-0.2
-0.2
-0.2
-0.1
-0.3
0.0
A
v
(ymA)
28.3
12.4
4.69
2.41
1.36
0. 76
0.44
0.047
OUTLET
Loading
mg
13.8
58.5
0.0
-0.1
0.0
0.0
-0.1
-0.1
-0.2
10.4
d
V
(ymA)
20.4
8.92
3.34
1.73
0.98
0.55
0.32
0.583
TABLE B-16.
INLET AND OUTLET PARTICLE DATA FOR BLANK RUN #19
Taken 2/5/78 at 10:30 am
IMPACTOR
STAGE
NUMBER
Probe
Pre-f ilter
1
2
3
4
5
6
7
Filter
S amp 1 e
Volume
(DNm3)
INLET
Loading
mg
14.2
122.2
0.3
0.0
0.0
-0.1
0.0
0.0
0.0
0.1
V
CymA)
26.6
11.7
4.42
2,28
1.29
0.72
0.42
0.042
OUTLET
Loading
rag
36.1
87.5
0.1
0.3
0.3
0.3
0.1
0.1
0.0
6.3
dpc
(ymA)
20.6
9.1
3.4
1.8
1.0
0.55
0.32
0.168
N: 20°C, 1 atm; d = dp (pp
; ymA = ymCg/cm3)31; pp = 2.3 g/cm3
53
-------
APPENDIX "C"
PARTICULATE SULFATE DATA
54
-------
TABLE C-l. RESULTS OF PARTICULATE SULFATE TESTS,
mg/DNm3 OF GAS SAMPLED
Run No.
Stage
1
2
3
4
5
6
7
Filter
Conditioned Tests
2
Inlet
2.10
1.05
0.90
0.30
0.30
0.30
0.30
0.30
Outlet
1.49
0.21
0.17
0.23
0.27
0.19
0.19
0.15
8
Inlet
1.14
0.33
1.14
0.49
0.33
0.65
0.65
0.49
Outlet
0.13
0.08
0.14
0.18
0.14
0.16
0.13
0.14
Baseline Tests
11
Inlet
*
*
*
*
*
2.60
*
*
Outlet
1.09
0.23
*
*
*
*
*
*
18
Inlet
1.08
*
*
*
*
*
*
*
Outlet
0.09
*
*
*
*
*
*
0.33
22
Inlet
*
*
*
*
*
*
*
*
Outlet
*
*
*
*
*
*
*
6.72
29
Inlet
*
*
*
*
*
*
*
*
Outlet
*
*
*
*
*
*
*
0.28
Ul
t/1
* Below detectable limit
-------
APPENDIX "D"
INPUT DATA FOR THE ESP PERFORMANCE MODEL
56
-------
TABLE D-l. INPUT DATA FOR THE ESP PERFORMANCE MODEL PROGRAM*
Case
Baseline
0.1-2 ym
Baseline
2-20 ym
S03 Conditioning
0.1-2 ym
SOj Conditioning
2-20 ym
d
Pi
8.5
8.5
8.5
8.5
a
g
4.0
4.0
4.0
4.0
a
1.16
0.948
2.85
2.25
b
0.300
0.817
1.06
2.33
c
0.212
-3.50x10-*
0.486
0.00265
y^c
0.36
0.36
0.36
0.36
a
0.25
0.25
0.25
0.25
N
2
2
2
2
S
0.1
0.1
0.1
0.1
di
0.1
2
0.1
2
df
2.0
20
2
20
Ad
0.1
1
0.1
1
Enter Data
Mass mean particle diameter, d ( ym) Number of baffled sections, Ng
t &
Geometric standard deviation, a Sneakage-reentrainment fraction, S
o
First curve fit parameter for migration velocity, a Initial particle diameter, d^ (ym)
Second curve fit parameter for migration velocity, b Final particle diameter, df (ym)
Third curve fit parameter for migration velocity, c Particle diameter increment, Ad (ym)
Specific collector area, A /Q,, (cm2/Acm3/sec)
Normalized standard deviation of gas velocity distribution, a
Sparks (1978)
-------
APPENDIX "E"
ELEMENTAL ANALYSIS DATA
58
-------
APPENDIX "E". ELEMENTAL ANALYSIS DATA
Thirty elements were included in the UC Davis X-ray
Analysis of the cascade impactor substrates. Of these thirty
only eight were present in significant amounts. Table E-l
lists the thirty elements and representative minimum resis-
tivities.
Table E-2 presents the weight per substrate area, by
cascade impactor stage, for the eight elements which were
present in large enough amounts to be of interest.
TABLE E-l. MINIMUM SENSITIVITIES OF ELEMENTS,
ng/cmz
Na 2,158 V 172 Hg 725
Mg 615 Cr 149 Pb 864
Al 653 Mn 150 Sn 374
Si 613 Fe 157 Ag 1,856
S 470 Co 151 Br 459
Cl 443 Ni 116 Rb 740
K 279 Cu 89 Sr 1,013
Ca 198 Zn 107 Zr 1,502
Ba 550 Pt 566 Mo 2,351
Ti 168 Au 652 Pd 4,660
59
-------
TABLE E-2. RESULTS OF ELEMENTAL ANALYSIS
OF FLY ASH ON CASCADE IMPACTOR
SUBSTRATES
00
3 4->
16*
1
2
3
4
5
6
7
34**
1
2
3
4
5
6
7
24**
1
2
3
4
5
6
7
ng/cm2
Al
2430
2657
8322
2836
2920
206
***
60832
21055
25877
25513
4621
4628
1750
***
11464
32192
37295
10990
3922
^1539
Si
5147
6870
15504
5222
5351
855
***
101540
37357
40427
41872
8201
8921
3483
1509
21887
52636
60104
20011
7084
2953
S
5665
8467
2543
4739
5904
4116
4399
***
1427
261
467
350
506
286
1133
3113
679
***
397
565
400
K
1434
1201
4276
1273
1562
510
148
21842
6452
9008
8380
1796
1686
743
5550
2923
10957
13488
3988
1530
655
Ca
3513
4365
4507
3926
2560
1508
1562
16813
12073
7398
7562
3886
4415
3817
7763
6252
9717
10504
6607
5410
1713
Ti
1940
1312
5180
1606
2212
784
604
29718
7032
10654
8568
2102
2046
1056
8802
3384
12378
14556
4372
1998
519
Fe
22088
20449
33215
10695
15078
5436
2100
201947
34750
62852
49857
12375
13017
5520
56112
17258
82818
99906
27685
11698
5211
Zn
244
277
266
166
257
155
165
1480
348
464
388
154
472
106
598
236
420
597
316
183
141
* Conditioned test
** Baseline test
*** Below significant limit
60
-------
TECHNICAL REPORT DATA
(Please read Inunctions on the reverse before completing)
1. REPORT NO.
EPA-600/7-79-104a
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Effects of Conditioning Agents on Emissions from
Coal-fired Boilers: Test Report No. 1
5. REPORT DATE
April 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
R.G.Patterson, P.Riersgard, R.Parker, and
S. Calvert
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Air Pollution Technology, Inc.
4901 Morena Boulevard, Suite 402
San Diego, California 92117
10. PROGRAM ELEMENT NO.
EHE624A
11. CONTRACT/GRANT NO.
68-02-2628
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOC C
Task Final; 1/78 - 4/78
COVERED
14. SPONSORING AGENCY CODE
EPA/600/13
,5. SUPPLEMENTARY NOTES
T£RL_RTp
j,
16.
The report gives results of a field performance test of an electrostatic precipitator
(ESP) which uses SOS an the conditioning agent. The ESP is at an electric utility
power plant, burning approximately 1% sulfur coal. Tests were conducted with and
without injection of the SO3. The ESP performance was characterized in terms of
particle collection efficiency and the chemical composition of particulate and gaseous
emissions. Fly ash resistivity and dust opacity were also measured. Results show
an average increase in overall efficiency from 80% to 95% with injection of the SOS.
This is accompanied by a decrease in fly ash resistivity, a decrease in opacity, and
an increase in SOS concentration entering and leaving the ESP. Approximately 80%
of the injected SOS escaped the ESP.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
Pollution
Flue Gases
Treatment
Coal
Combustion
Sulfur Trioxide
Electrostatic Pre-
cipitation
Fly Ash
Electrical Resisti-
vity
Opacity
b.lDENTIFIERS/OPEN ENDED TERMS
Pollution Control
Stationary Sources
Conditioning Agents
c. COSATl Field/Group
13B
21B
14B
21D
07B
13H
20C
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
71
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
61
------- |