EPA
United States
Environmental Protection
Agency
Office or Air Quality
Planning and Standards
Research Triangle Park NC 27711
EMB Report 85-CHM-8
May 1985
Air
Chromium Screening
Study Test Report
Refuse To Energy
Incinerator
Baltimore Resco
Baltimore, Maryland
-------
EMISSION TEST REPORT
METHOD DEVELOPMENT AND TESTING
FOR CHROMIUM
No. 2 Refuse-to-Energy Incinerator
Baltimore RESCO
Baltimore, Maryland
ESED Project No. 85/2
EMB Report 85-CHM-8
by
PEI Associates, Inc.
11499 Chester Road
P.O. Box 46100
Cincinnati, Ohio 45246-0100
Contract No. 68-02-3849
Work Assignment Nos. 14, 18, and 22
PN 3615-14, 3615-18, and 3615-22
Task Manager
Mr. Frank Clay
Emission Standards and Engineering Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
EMISSION MEASUREMENT BRANCH
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
August 1986
-------
DISCLAIMER
This report was furnished to the U.S. Environmental Protection Agency,
Emission Measurement Branch, by PEI Associates, Inc., Cincinnati, Ohio, in
fulfillment of Contract No. 68-02-3849, Work Assignment Nos. 14, 18, and 22.
Its contents are reproduced herein as received from PEI. The opinions,
findings, and conclusions are those of the authors and not necessarily those
of the EPA. Mention of company or product names does not constitute endorse-
ment or recommendation for use.
ii
-------
CONTENTS
Page
Figures iv
Tables y
Quality Assurance Element Finder vi
Acknowledgment vii
1. Introduction 1-1
2. Summary and Discussion of Test Results 2-1
2.1 Test protocol 2-1
2.2 Particulate, hexavalent chromium, and arsenic
test results 2-4
2.3 Particle size distribution test results 2-10
2.4 Process sample analytical results 2-16
2.5 Visible emissions and hi-volume sample 2-17
2.6 Total chromium and other metals test results 2-20
3. Quality Assurance 3-1
4. Sampling Locations and Test Procedures 4-1
4.1 Sampling location 4-1
4.2 Particulate and hexavalent chromium sample extraction
and analysis 4-1
4.3 Particle size distribution 4-7
4.4 Process samples 4-9
4.5 Arsenic 4-10
5. Process Description 5-1
Appendices
A Computer Printouts and Example Calculations A-l
B Field Data Sheets B-l
C Laboratory Data C-l
D Sampling and Analytical Procedures D-l
E Calibration Procedures and Results E-l
F Quality Assurance Summary F-l
G Project Participants and Sample Log G-l
H Draft Test Method for Hexavalent Chromium Emissions From
Stationary Sources H-l
I Draft Protocol for Determination of Total Chromium Emissions
From Stationary Sources 1-1
iii
-------
FIGURES
Number Page
2-1 No. 2 ESP Inlet Particle Size Distribution 2-12
2-2 No. 2 ESP Outlet Particle Size Distribution 2-13
2-3 ESP Hopper Fly Ash Sampling Location 2-18
2-4 Hi-Volume Sampler 2-19
4-1 No. 2 Incinerator ESP Inlet Sampling Location (No Scale) 4-2
4-2 No. 2 Incinerator ESP Outlet Sampling Location (No Scale) 4-3
5-1 No. 2 Incinerator Exhaust Gas Flow Schematic 5-2
IV
-------
TABLES
Number Page
2-1 Sampling and Analytical Parameters, No. 2 Furnace and ESP 2-2
2-2 Summary of Sample and Flue Gas Data for Particulate/Cr
and Arsenic Tests 2-5
2-3 Summary of Particulate and Hexavalent Chromium Emissions
Data 2-6
2-4 Summary of Arsenic Emissions Data 2-9
2-5 Comparison of Particulate Concentrations as Measured by
EPA Method 5 Versus Particle Size Distribution Impactors 2-14
2-6 Process Sample Analytical Results 2-16
2-7 Summary of Total Cr Emission Data 2-21
2-8 Summary of Beryllium, Lead, and Zinc Analytical Data 2-24
3-1 Field Equipment Calibration 3-3
3-2 Example Filter and Reagent Blank Analysis for Particulate 3-4
3-3 Linear Regression Data Spectrophotometer Calibration 3-5
3-4 Results of QC Samples 3-6
3-5 QC Data for Total Chromium by NAA 3-7
-------
QUALITY ASSURANCE ELEMENT FINDER
Location
Section Page
(1) Title page
(2) Table of contents
(3) Project description
(4) QA objective for measurement of data in terms
of precision, accuracy, completeness, repre-
sentativeness, and comparability
(5) Sampling procedures
(6) Sample custody
(7) Calibration procedures and frequency
(8) Analytical procedures
(9) Data reduction, validation, and reporting
(10) Internal quality control checks and frequency
(11) Performance and system audits and frequency
(12) Preventive maintenance procedures and schedules
(13) Specific routine procedures used to assess data
precision, accuracy, and completeness of specific
measurement parameters involved
(14) Corrective action
(15) Quality assurance reports to management
—
1
Appendix F
Section 3
Appendix D
Section 4
Appendix C
Appendix E
Section 3
Appendix D
Section 4
Appendix F
Section 3
Appendix F
Section 3
Appendix F
Section 3
Appendix F
m
1-1
F-2
D-l
C-l
E-l
D-l
F-3
F-5
F-3
F-12
Appendix F F-4
Appendix F F-ll
Appendix F F-12
VI
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ACKNOWLEDGMENT
This test program was conducted for the Emission Standards and Engineer-
ing Division of the EPA Office of Air Quality Planning and Standards.
Mr. Frank Clay, Emission Measurement Branch (EMB) Task Manager, provided
overall project coordination and guidance and Mr. Ed McCarley of EMB observed
part of the test program. Mr. Ron Myers, Industrial Studies Branch (ISB)
project engineer and Mr. Dwight Atkinson, representing Midwest Research
Institute (MRI) (an EPA contractor), monitored process operation throughout
the test period. Mr. Charles Bruffey was the PEI Project Manager. Principal
authors were Messrs. Charles Bruffey and Thomas Wagner.
-------
SECTION 1
INTRODUCTION
The U.S. Environmental Protection Agency (EPA) is currently evaluating
several potentially toxic metals and their compounds. One of these toxic
metals is chromium. Neither New Source Performance Standards (NSPS) for
stationary sources nor National Emissions Standards for Hazardous Air Pollu-
tants (NESHAPS) currently include chromium emissions. Available data on the
emission of chromium and its impact on air quality are limited.
The Emission Measurement Branch (EMB) of EPA's Environmental Standards
and Engineering Division (ESED) requires contractor assistance in obtaining
representative chromium emissions data from several source categories so that
an accurate assessment of the potential problems can be made and appropriate
regulatory action developed.
PEI Associates, Inc. (under contract to ESED-EMB) performed a series of
atmospheric emission tests on the No. 2 municipal refuse incinerator operated
by Signal Environmental Systems, Inc. (SES) for the city and county of Balti-
more, Maryland. All testing took place during the period of May 14 through
16, 1985. Test objectives were met and no major problems were encountered
during sampling or analysis.
Triplicate tests were conducted simultaneously at the inlet and outlet
of an electrostatic precipitator (ESP) used to control particulate emissions
from the incinerator to determine the concentrations and mass emission rates
of particulate matter, hexavalent chromium (Cr ), total chromium (Cr),
1-1
-------
beryllium (Be), cadmium (Cd), nickel (Ni), lead (Pb), and zinc (Zn). In
addition, particle size distribution tests were conducted during the partic-
ulate/chromium tests at each location, and process samples (incinerator
bottom ash, and ESP hopper fly ash) were collected and analyzed for Cr ,
total chromium, and metals.
At the completion of the particulate/chromium tests, a single test was
conducted simultaneously at each location to determine the concentration and
mass emission rate of inorganic arsenic.
Section 2 summarizes and discusses the test results; Section 3 addresses
quality assurance considerations specific to this project; Section 4
describes the sampling locations and test procedures; and Section 5 describes
source operation. Appendix A presents sample calculations and computer
printouts; Appendices B and C contain the field data sheets and laboratory
analytical results, respectively; Appendix D details the sampling and analyt-
ical procedures; Appendix E summarizes equipment calibration procedures and
results; Appendix F presents a project quality assurance summary; Appendix G
contains a list of project participants and a sampling log; Appendix H pre-
sents the draft test method for hexavalent chromium emissions from stationary
sources; and Appendix I presents the draft protocol for determining total
chromium emissions from stationary sources.
It should be noted that EPA performed the total chromium, cadmium, and
nickel analysis of collected samples by neutron activation analysis (NAA).
PEI performed the analysis for the other metals using Inductively Coupled
Argon Plasma (ICAP) spectroscopy analytical techniques.
1-2
-------
SECTION 2
SUMMARY AND DISCUSSION OF TEST RESULTS
This section details the results of the sampling program. Subsections
are used to identify results from each test type (i.e., particulate/Cr ,
particle size distribution, etc.), and results are expressed in both metric
and English units where applicable.
2.1 TEST PROTOCOL
Table 2-1 presents the sampling and analytical protocol followed
throughout this project, the test identification, and the sampling times for
each specific test type.
In summary, EPA Method 5* sampling trains were used for simultaneous
extraction of samples from the ESP inlet and outlet test locations. Samples
were collected over a 5-hour period by isokinetic, cross-sectional traverse
sampling techniques.
A total of six samples (three inlet and three outlet) were collected for
determination of particulate and Cr concentrations. Method 5 analytical
procedures were followed for the particulate analysis, and procedures re-
cently developed by EPA for determination of Cr content in source emission
samples were used for the Cr analysis. These latter procedures entail
extraction of the sample fractions (probe residue and filter particulate)
40 CFR 60, Appendix A, Reference Method 5, July 1984.
2-1
-------
TABLE 2-1. SAMPLING AND ANALYTICAL PARAMETERS, NO. 2 FURNACE AND ESP
Run No.
PCI-1
PCO-1
PC I -2
PCO-2
PCI-3
PCO-3
PSI-1
PSO-1
PS I -2
PSO-2
PS I -3
PSO-3
AI-1
AO-2
PCI(l-3)
PCO(l-3)
AI-1
AO-1
Date (1985)
and tine (24-h)
5/14 - 0834-1544
5/14 - 0836-1401
5/15 - 0841-1439
5/15 - 0842-1403
5/16 - 0822-1422
5/16 - 0822-1344
5/14 - 1413-1613
5/14 - 1030-1400
5/15 - 1246-1516
5/15 - 1000-1500
5/16 - 1238-1508
5/16 - 0945-1445
5/16 - 1513-1804
5/16 - 1517-1738
5/14-16
Test or sample type
Pajticulate
Total Cr
Particle
size
distribution
Arsenic
Process samples
Incinerators bottom
ash - fly ash (com-
bined from 3 units)
No. 2 ESP hopper
fly ash
Sampling
location
Inlet
Outlet
Inlet
Outlet
Inlet
Outlet
Inlet
Outlet
Inlet
Outlet
Inlet
Outlet
Inlet
Outlet
Sample parameters
Particulate
Methods
1-5
X
X
X
X
X
X
_
-
-
-
.
-
.
-
-
-
Particle
size dis-
tribution
-
-
-
.
-
X
X
X
X
X
X
.
-
-
-
Cr+6
X
X
X
X
X
X
_
-
-
-
.
-
_
-
-
-
Total
Cr
X
X
X
X
X
X
.
-
.
-
.
-
_
-
-
-
Arsenic
Method 108
-
-
-
.
-
_
-
.
-
_
-
X
X
Analytical parameters
Partic-
ulate
Method 5
X
X
X
X
X
X
_
-
.
-
_
-
_
-
-
-
Particle
size dis-
tribution
-
-
-
_
-
X
X
X
X
X
X
_
-
-
-
Cr+6
X
X
X
X
X
X
-
-
Total Cr
by NAA
X
X
X
X
X
X
X
_
-
X
X
Arsenic
Method
108
-
.
-
.
-
_
-
_
-
_
-
X
X
X
X
Other
metals
by NAA
X
X
X
X
X
X
_
.
.
-
X
-
_
-
X
X
ro
i
ro
aAnalysis currently being performed by U.S. EPA.
-------
with an alkaline solution followed by the diphenylcarbazide colorimetric
method.* An analytical Cr detection limit of 0.1 microgram per gram (yg/g)
was established for these samples.
Particle size distribution measurements were made at each site during
the particulate/Cr tests with an Andersen heavy grain loading impactor
(HGLI) at the ESP inlet and an Andersen Mark III multistage impactor at the
ESP outlet. Three samples were collected at each location. Particle size
fractions were analyzed gravimetrically, and size distribution curves were
developed for each site.
At the completion of the particulate/Cr and particle size tests, a
single test was conducted simultaneously at each location according to proce-
dures described in EPA Reference Method 108.** Method 108 provides inorganic
arsenic concentration. This test was conducted for about 2 hours at each
location by isokinetic, cross-sectional traverse techniques. Total arsenic
content was then determined by atomic absorption (AA) analysis.
The following process samples were collected during each emission test.
0 A composite incinerator bottom ash-fly ash sample representing
combined material from all three units, and
0 No. 2 ESP hopper fly ash samples.
Select samples were analyzed for Cr using procedures similar to those
performed on the Method 5 particulate samples. Process and emission samples
were then shipped to EPA for analysis of total Cr by NAA. PEI later per-
formed ICAP analysis on ESP fly ash samples for Be, Pb, and Zn.
The following subsections detail the results of the sampling program.
Test Methods for Evaluating Solid Waste. U.S. EPA SW-846, 2nd ed., July
1982.
**
40 CFR 60, Appendix A, Reference Method 108, July 1984.
2-3
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2.2 PARTICULATE, HEXAVALENT CHROMIUM, AND ARSENIC TEST RESULTS
Simultaneous Method 5* tests were conducted at the ESP inlet and outlet
test locations. These samples were analyzed for particulate and Cr concen-
trations, and the resulting data were used to characterize the removal effi-
ciency across the ESP. In addition, a single test was conducted simultane-
ously at each location (by EPA Method 108 sampling and analytical procedures)
to characterize uncontrolled and controlled arsenic emissions from this type
of source. During all testing, the incinerator load was at least 80 percent
of rated capacity (see Section 5).
Table 2-2 summarizes pertinent sample and flue gas data for the particu-
late/Cr and arsenic tests, and Table 2-3 presents the reported particulate
and Cr emission results.
Volumetric flow rates are expressed in cubic meters per minute (m3/min)
and actual cubic feet per minute (acfm) at stack conditions. Flow rates
corrected to standard conditions [20°C and 760 mmHg (68°F and 29.92 in.Hg)
and zero percent moisture] are expressed as dry normal cubic meters per
minute (dNm3/min) and dry standard cubic feet per minute (dscfm).
Filterable particulate concentrations are expressed in milligrams per
dry normal cubic meter (mg/dNm3) and grains per dry standard cubic foot
(gr/dscf). Filterable particulate represents that material collected in the
sample probe and on the sample filter, which were both maintained at approxi-
mately 121°C (250°F). Hexavalent chromium concentrations are expressed in
micrograms per gram (yg/g) and micrograms per dry normal cubic meter
(yg/dNm3), where applicable. Mass emission rates are reported in kilograms
per hour and pounds per hour.
*40 CFR 60, Appendix A, Reference Method 5, July 1984.
2-4
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TABLE 2-2. SUMMARY OF SAMPLE AND FLUE GAS DATA FOR PARTICULATE/Cr+6 AND ARSENIC TESTS
ro
i
en
Run
No.
PCI-1
PCO-1
PC I -2
PCO-2
PC I -3
PCO-3
PCI (I
Date
(1985)
5/U
5/14
5/15
5/15
5/16
5/16
ilet) a\
PCO (Outlet) <
AI-1
(Arsen
AO-1
5/16
c)
5/16
Sampling
duration,
mm
300
300
300
300
300
300
erage
verage
125
125
Sample
volume
dNm'
6.77
7.61
2.53
7.67
2.30
7.64
-
-
0.97
3.10
dscf
239.228
268.673
89.164
270.671
81.325
269.762
-
-
34.339
109.527
Isokinetic
sampling
rate, I
95.6
95.8
96.2
99.0
94.7
100.3
-
-
95.7
100.6
Volumetric flow ratea
Actual
m'/min
6768
6284
7117
6008
6706
6006
6864
6119
6729
5913
acfm
239.000
221.900
251.300
212.150
236 .800
214.200
242,400
216.000
237,600
208.800
Standard
dNmVmin
3427
3172
3639
3095
3370
3044
3479
3104
3381
2959
dscfm
121,000
112.000
128.500
109,300
119,000
107,500
122,800
109,600
119,400
104,500
Temperature
"C
241
235
239
232
239
233
239
233
238
232
"F
465
455
463
449
462
452
463
452
461
449
Moisture
content,
%
11.3
12.0
11.4
11.6
12.2
12.7
11.6
12.1
12.4
13.1
Gas compo-
sition. a X
0,
11.2
11.2
11.6
11.6
11.3
11.6
11.4
11.5
11.3
11.6
C02
7.4
7.4
7.1
7.2
8.4
8.0
7.6
7.5
8.4
8.0
CO
0
0
0
0
0
0
0
0
0
0
Gas
velocity
mps
15.0
17.2
15.8
16.4
14.8
16.6
15.2
16.7
14.9
16.2
fps
49.2
56.3
51.7
53.8
48.7
54.3
49.9
54.8
48.9
53.0
"standard conditions: 20°C (68°F), 760 mmHg (29.94 in.Hg) and zero percent moisture.
Gas composition as determined from integrated bag samples collected during each test. Analysis performed with an Orsat gas analyzer.
Measured flue gas velocity In meters per second and feet per second.
-------
TABLE 2-3. SUMMARY OF PARTICULATE AND HEXAVALENT CHROMIUM EMISSIONS DATA
Run
No.
PCI-1
PCO-1
PC I -2
PCO-2
PC I -3
PCO-3
Date
(1985)
5/14
5/14
5/15
5/15
5/16
5/16
Filterable concentration
Total
filterable
weight, grams
21.188
0.0374
7.07
0.0316
6.849
0.0253
Participate3
mg/dNm3
3130
4.9
2795
4.1
2978
3.3
gr/dscf
1.4
0.002
1.2
0.0018
1.3
0.0014
wg/g
<0.1
NA
<0.1
NA
<0.1
NA
Cr ° (blank corrected)"
Total Cr+6
in sample, ug
<0.5
NA
<0.5
NA
<0.5
NA
ug/dNm3
.
-
_
-
_
~
Mass emission rate
Particulate
kg/h
643
0.95
611
0.8
601
0.6
Ib/h
1418
2.1
1348
1.7
1325
1.3
Ci
kg/h
.+6
Ib/h
Collection
efficiency, %
Particulate
>QQ R
CrTO
Participate .
concentration
in gr/dscf
corrected
to 12% COj
2.27
0.003
2.03
0.003
1.86
0.002
ro
01
aStandard conditions: 20°C (68°F), 760 mmHg (29.94 in.Hg) and zero percent moisture.
A Cr detection limit of 0.1 ug/g was established for these samples based on a particulate weight of 5 grams using 50 ml total volume.
Election efficiency: Inlet concentration -^tlet^ncentration , 10Q
L12
12C
where C,, = corrected concentration
C = uncorrected concentration
% CO. = as measured by Orsat gas analyzer
NA - Not analyzed.
-------
As reported in Table 2-2, sample volumes ranged from 2.30 to 6.77 dNm3
for the inlet trains and from 7.61 to 7.67 dNm3 for the outlet trains. The
inlet sample rate was adjusted after Test PCI-1 to account for the heavy
particulate loading at this site. The particulate filter was changed four
times during this run to prevent excessive pressure drop across the filter
frit support. Tests PCI-2 and PCI-3 were run at substantially lower sampling
rates to preclude excessive pressure drop and filter changes during testing.
No problems were encountered during Runs 2 and 3 and sufficient sample (>5
grams) was collected for Cr quantification. Isokinetic sampling rates
ranged between 94.7 and 100.3 percent, which is within the acceptable range
of 90 to 110 percent.
Volumetric gas flow rates at the ESP inlet ranged from 6706 to 7117
m3/min (236,800 to 251,300 acfm) and averaged 6864 m3/min (242,400 acfm) for
the three particulate/Cr tests. The average volumetric flow at standard
conditions was 3479 dNm3/min (122,800 dscfm). Flue gas temperatures ranged
from 239° to 241°C (462° to 465°F) and averaged 239°C (463°F). The moisture
content of the gas stream averaged 11.6 percent, and the average oxygen (Op)
and carbon dioxide (COp) contents were 11.4 and 7.6 percent, respectively.
Arsenic sample and flue gas data reported in Table 2-2 are comparable to
data associated with the particulate/Cr tests with the exception of the
sample times and metered gas volume.
As shown in Table 2-3, inlet particulate concentrations ranged from 2795
to 3130 mg/dNm3 (1.2 to 1.4 gr/dscf) and averaged 2968 mg/dNm3 (1.3 gr/dscf).
The average mass emission rate for the three tests was 618 kg/h (1364 Ib/h).
As reported in Table 2-3, hexavalent chromium content of the inlet
emission samples was less than 0.1 pg/g, or below the detection limit of the
2-7
-------
analytical methodology employed. Because of the extended sampling times and
heavy participate concentration at this location, loose participate in gram
quantities was collected in the front half of each Method 5 sampling train.
Considering the extremely low levels of Cr indicated by the pretest survey
sample analysis (<0.25 yg/g), the filters were not cut up and extracted as
specified in the method. This precluded the need for a filter blank correc-
tion for Cr . Rather, the loose particulate was thoroughly mixed with a
Teflon spatula and approximately 5 grams of the particulate was transferred
to the beaker containing the probe rinse particulate residue. To increase
the analytical sensitivity (0.1 yg/g), the amount of alkaline extraction
solution and the final dilution volume were kept at a minimum consistent with
Method 3060 from Test Methods for Evaluating Solid Waste.* This proportion
is 4 ml of extraction solution per gram of solid diluted to a final volume of
10 ml. Filters would require larger amounts of extraction solution resulting
in increased analytical detection limits (>1.0 yg/g).
At the ESP outlet, volumetric gas flow rates ranged from 6006 to 6284
m3/min (214,200 to 221,900 acfm) and averaged 6119 m3/min (216,000 acfm).
The average gas flow rate at standard conditions was 3104 dNm3/min (109,600
dscfm). Flue gas temperatures ranged from 232° to 241°C (449° to 465°F) and
averaged 233°C (452°F). The moisture content of the gas stream averaged 12.1
percent, and the average 02 and COp contents were 11.5 and 7.5 percent,
respectively.
Outlet particulate concentrations ranged between 3.3 and 4.9 mg/dNm3
(0.0014 and 0.002 gr/dscf) and averaged 4.1 mg/dNm3 (0.0017 gr/dscf). The
average mass emission rate for the three tests was 0.8 kg/h (1.7 Ib/h).
United States Environmental Protection Agency, SW846, 2nd ed., July 1982.
2-8
-------
Since Cr levels in the ESP inlet samples were less than detectable, no
attempt was made to analyze the ESP outlet participate samples for Cr .
The particulate-removal efficiency of the ESP was greater than 99.8
percent based on the measured inlet and outlet particulate concentrations.
No major problems were encountered during the particulate/Cr tests.
Extended sampling times were necessary to assure collection of sufficient
loose particulate sample at the ESP inlet so that Cr levels could be quan-
tified. It should be noted that one of the six sampling ports at the ESP
outlet location was not accessible for sampling because of an I-beam support
approximately 4 feet directly in front of the port opening. Each of the
remaining 5 sampling ports was sampled using 5 points per port for a total of
25 sampling points. The effect on sample results is believed to be insignif-
icant considering the low particulate weights and extended sampling times.
Table 2-4 summarizes the arsenic emissions data obtained at this source.
TABLE 2-4. SUMMARY OF ARSENIC EMISSIONS DATA
Run No.
AI-1
AO-1
Date
(1985)
5/16
5/16
Sampling
location
Inlet
Outlet
Concentration
Total3
arsenic sample
weight, yg
162.7
13.1
yg/dNm3
167.7
4.2
mg/dNm3
0.17
0.004
Arsenic
collection
efficiency, %
>97
aProbe rinse residue, filter and impinger catch.
The inlet sample showed a total arsenic weight of 162.7 yg or 167.7
vg/dNm3 compared with 13.1 yg (4.2 yg/dNm3) for the outlet sample. This
single test indicated an arsenic collection efficiency of more than 97 per-
cent. Considering the low level of arsenic measured, and based on a single
2-9
-------
test, this calculated efficiency is comparable to the overall participate
collection efficiency of the ESP.
2.3 PARTICLE SIZE DISTRIBUTION TEST RESULTS
At the ESP inlet, an Andersen HGLI with a 15-ym precutter attached was
used to measure particle size distribution during each particulate/Cr test.
This in-stack impactor consists of two single-jet impaction chambers followed
by a third-stage cyclone and a backup thimble. The impactor is designed for
use in extracting samples from a gas stream with a heavy particulate concen-
tration and its use was advantageous in this case because it contains no
filter media (except the backup thimble). This eliminates the need for
filter blank corrections for Cr and permits a more accurate quantification
of Cr size distribution. A total of three inlet samples (designated PSI)
were collected during 120- to 150-minute periods at a single point repre-
senting the average gas velocity and temperature in the duct.
At the ESP outlet, an Andersen Mark III in-stack impactor was used to
measure size distribution during the particulate/Cr tests. The Mark III
impactor consists of eight stages and a backup filter from which eight cut-
point sizes can be determined.
Three samples (designated PSO) were collected from a single point repre-
senting the average velocity head and temperature in the duct. Sample times
ranged from 210 to 300 minutes.
Each particle size test was conducted according to the procedures
described in the impactor operations manuals. Isokinetic sampling rates were
set initially, and constant cut-point characteristics were maintained
throughout the sampling period. Specifications state that the gas flow rate
2-10
-------
through the impactor at stack conditions should be maintained between 0.3 and
0.7 acfm to avoid distortion of individual stage cut-points. With the excep-
tion of Test PSO-2, which exhibited a 0.71 cfm impactor flow rate, this
criterion was met. Isokinetic sampling rates ranged from 99.6 to 103.9
percent for the inlet tests and 103.1 to 106 percent for the outlet tests.
Cumulative size distribution curves representing the total weight of
particulate matter smaller than the indicated aerodynamic particle diameter
[in micrometers (ym)] were established for each test location. Data reduc-
tion for all runs were performed by computer programming with moisture,
molecular weight, and temperature data obtained from the particulate/Cr
tests. The cut-points for the HGLI tests were determined graphically from
information supplied by the manufacturer, and all particle size results are
based on a particle density of 1 g/cm3. The HGLI data reduction and inter-
mediate calculations are presented in Appendix A of this report.
Cut-points for the Mark III impactor stages were calculated by use of a
computer program contained in "A Computer-Based Cascade Impactor Data Reduc-
tion System" (CIDRS) developed for EPA by Southern Research Institute (SRI).*
All particle size results are based on a particle density of 1 g/cm3.
Figures 2-1 and 2-2 present the best-fit nominal curves for the inlet
and outlet particle size distribution tests. Table 2-5 presents a comparison
of particulate concentrations obtained from the particle size tests with
those obtained by Method 5 tests.
For the three inlet runs (PSI-1 through -3), the size distribution curve
showed that about 40 percent by weight of the particles had a nominal
*
Southern Research Institute. A Computer-Based Cascade Impactor Data Reduc-
tion System. Prepared for U.S. EPA under Contract No. 68-022-131, March
1978.
2-11
-------
ro
ro
10.0
PARTICLE SIZE, micrometers
100
Figure 2-1. No. 2 ESP inlet particle size distribution.
-------
ro
i
~n
l.Q 10.0
PARTICLE SIZE, micrometers
100
Figure 2-2. No. 2 ESP outlet particle size distribution.
-------
TABLE 2-5. COMPARISON OF PARTICULATE CONCENTRATIONS AS MEASURED BY
EPA METHOD 5 VERSUS PARTICLE SIZE DISTRIBUTION IMPACTORS
Run No.
PSI-1
PCI-1
PSI-2
PCI-2
PSI-3
PCI-3
PSO-1
PCO-1
PSO-2
PCO-2
PSO-3
PCO-3
Test location
ESP inlet
ESP outlet
Sample type
Particle size - HGLI
Method 5 - Parti cul ate
Particle size - HGLI
Method 5 - Parti cul ate
Particle size - HGLI
Method 5 - Particulate
Particle size
Method 5 - Particulate
Particle size
Method 5 - Particulate
Particle size
Method 5 - Particulate
Particulate concentration
mg/dNm3
2515
3130
1756
2795
2206
2978
2.99
4.9
3.0
4.1
2.87
3.3
gr/dscf
1.1
1.4
0.8
1.2
1.0
1.3
0.0013
0.002
0.0013
0.0018
0.00125
0.0014
2-14
-------
diameter of 15 micrometers or less. The calculated average participate
concentration for these runs was 2159 mg/dNm3 (0.97 gr/dscf) compared with a
three-test Method 5 average of 2968 mg/dNm3 (1.3 gr/dscf). This indicates
about a 25 percent difference in average values between the two measurements.
The percentage difference between the methods is acceptable according to the
applicable criterion in the Inhalable Particulate (IP) protocol.* This
protocol states that a comparison of the total mass concentrations between
particle size and Method 5 sample runs should not differ from the means by
more than 50 percent.
The HGLI Stages 1, 2, and 3 cut-points for Test PSI-1 were 13.0, 6.9,
and 2.4 ym, respectively. Seventeen percent of the particles were less than
13.0 ym, 14 percent were less than 6.9 pm, and 12.5 percent were less than
2.4 ym. The stage cut-points for Test PSI-2 were 13.0, 6.9, and 2.2 ym.
Thirty-four percent of the particles were less than 13.0 ym, 31 percent were
less than 6.9 ym, and 28 percent were less than 2.2 ym. The stage cut-points
for Test PSI-3 were identical to those of Test PSI-1. Twenty-one percent of
the particles were less than 13 ym, 19 percent less than 6.9 ym, and 16
percent less than 2.4 ym.
The size distribution curves for the three outlet tests (PSO-1 through
-3) showed between 60 and 70 percent by weight of the particles had a nominal
diameter of 10 ym or less. Approximately 45 percent of the particles were
less than 2 ym. The average calculated particulate concentration for these
runs was 2.94 mg/dNm3 (0.0013 gr/dscf) compared with a three-test Method 5
average of 4.1 mg/dNm3 (0.0017 gr/dscf).
*
Procedures Manual for Inhalable Particulate Samplers Operation, prepared by
Southern Research Institute for EPA, Contract No. 68-02-3118, November 1979.
2-15
-------
The inlet results are considered representative of particle size dis-
tribution in the gas stream at the time of testing. The overall data con-
sistency and comparability to the average Method 5 results substantiate this
conclusion.
The outlet results are somewhat suspect because of the extremely low
particulate concentration. Some distortion in stage cut-points is also
expected as a result of physical forces such as static electricity. However,
the data are comparable and correlate favorably with the Method 5 test re-
sults.
Based on the nondetectable levels of Cr at this source, no attempt was
made to quantify Cr by size fraction.
2.4 PROCESS SAMPLE ANALYTICAL RESULTS
Table 2-6 summarizes Cr analytical results from the composite incin-
erator bottom ash-fly ash, and ESP hopper fly ash samples.
TABLE 2-6. PROCESS SAMPLE ANALYTICAL RESULTS
Sample type
Incinerator bottom ash
(composite)
ESP hopper fly ash
No. 4 field (5/14)
No. 4 field (5/15)
No. 4 field (5/16)
Labora-
tory ID
EL143-145
-
EL155
EL156
EL157
Particu-
late weight
analyzed, g
10.1712
-
10.0836
10.0297
10.0133
Total
Cr+6, yg
<1
-
<1
<1
<1
Cr concen-
tration, yg/g
<0.1
-
<0.1
<0.1
<0.1
Detection limit: 0.1 yg/g.
Samples of the combined bottom ash-ESP fly ash were collected each test
day from a vibrating screen conveyor immediately prior to being loaded into
2-16
-------
trucks for disposal in a landfill. This material represented a nonhomogene-
ous mixture of bottom ash and ESP fly ash from each of the three units at
this facility. Grab samples were collected 4 to 6 times over a 5-hour test
period and placed in a 1-gallon polyethylene container. Samples from each
test day were composited into a single sample and analyzed for Cr using
procedures similar to those used in the analysis of the inlet Method 5 sam-
ples. Cr content in this sample was less than the detection limit (<0.1
ug/g).
Samples of the No. 2 ESP hopper fly ash were collected from each of four
ESP fields during each test day. Figure 2-3 depicts the sampling location.
Only samples collected from the No. 4 field were analyzed for Cr . The Cr
level in these samples was less than detectable (<0.1 wg/g).
2.5 VISIBLE EMISSIONS AND HI-VOLUME SAMPLE
As instructed by EPA, PEI attempted to collect sufficiently large quan-
tities of particulate at the ESP outlet so that Cr and other metals of
interest could be quantified. Pretest calculations revealed that sampling
times in excess of 30 hours, using a hi-volume sampler, would be required to
collect s750 mg from this source. A hi-volume ambient air sample pump and
filter were used as shown in Figure 2-4. However, the sample runs were
terminated with less than 2i hours of sample time due to overheating of the
pump motor. Sample volumes corrected to standard conditions for these runs
were 433 and 665 dNm3 (1419 and 2183 dscf), respectively.
No attempt was made to analyze these samples based on the analytical
results for Cr from the inlet and process samples.
2-17
-------
A SIDE
B SIDE
MAIN ASH CONVEYOR
MAIN
INCINERATOR
BUILDING
1
ESP f
2
IELD
3
4
MAIN
O
STACK
GAS FLOW
Figure 2-3. ESP hopper fly ash sampling location.
2-18
-------
ro
vo
STACK WALL
MANOMETER
ICE BATH H RECIRCULATION
Figure 2-4. Hi-volume sampler.
-------
2.6 TOTAL CHROMIUM AND OTHER METALS TEST RESULTS
Table 2-7 summarizes total Cr concentration and emission data for sam-
ples analyzed by NAA. Analytical data as received from EPA are included in
Appendix C of this report along with example calculations. Table 2-8 summa-
rizes Be, Pb, and Zn concentration data for process samples analyzed using
ICAP techniques.
As reported in Table 2-7, inlet Method 5 tests designated PCI-1 through
-3 and outlet Method 5 tests designated PCO-1 through -3 were submitted for
analysis. In addition, inlet particle size run PSI-3 was submitted for
analysis by individual stage cut point. Process samples (fly ash/bottom ash
and ESP fly ash) were also analyzed for total Cr.
The total Cr content of the inlet emission samples ranged between 657
and 861 yg/g. Total Cr concentrations ranged between 1836 and 2695 yg/dNm3,
with corresponding mass emission rates ranging between 0.40 and 0.55 kg/h
(0.90 and 1.04 Ib/h).
The total Cr content of the outlet emission samples ranged between 2807
and 7545 yg/g. The total Cr concentration ranged between 11.6 and 27.3
yg/dNm3, with corresponding mass emission rates of 0.002 and 0.005 kg/h
(0.005 and 0.01 Ib/h), respectively. All outlet total Cr data have been
corrected for a filter/acetone Cr blank level of 15 yg. These data indicate
that the total Cr collection efficiency of the ESP is about 99 percent on a
mass rate basis.
A single particle size sample from the ESP inlet was analyzed by indi-
vidual stages in an attempt to characterize total Cr by size fraction. As
reported in Table 2-7, the total Cr content of individually-loaded stages
ranged from 330 ug for Stage 1, 13 ym cut point, to 139 yg for Stage 3, 2.4
cut point.
2-20
-------
TABLE 2-7. SUMMARY OF TOTAL Cr EMISSION DATA
(Baltimore RESCO)
ro
i
ro
Run
No.
PC1-1
PC I -2
PC1-3
PCO-1
PCO-2
PCO-3
PSI-3
PSI-3
1SI-3
1SI-3
PSI-3
1-3
(PCI
and
PCO
1)
(PCI
and
PCO
2)
Sample type
and location
Participate - ESP inlet
Participate - ESP inlet
Paniculate - ESP inlet
Paniculate - ESP outlet
Particulate - ESP outlet
Particulate - ESP outlet
Particle size - ESP
inlet
Stage 0
Particle size - ESP
inlet
Stage 1
Particle size - ESP
inlet
Stage 2
Particle size - ESP
inlet
Stage 3
Particle size - ESP
inlet
Backup thimble
Fly ash/bottom ash
Composite
ESP fly ash - Field 1
ESP fly ash - Field 2
ESP fly ash - Field 3
ESP fly ash - Field 4
ESP - fly ash - Field 1
ESP - fly ash - Field 2
ESP - fly ash - Field 3
ESP - Fly ash - Field 4
Total8
participate
collected,
g
21.1876
7.0703
6.8494
0.0374
0.0316
0.0253
1.3899
0.4523
0.0634
0.0606
0.3725
-
-
-
Particulate
sample weight
analyzed by
NAA, g
0.0991
0.1059
0.1097
0.0374
0.0316
0.0253
0.0962
0.1022
0.0433
0.0405
0.3725
0.1278
0.098
0.1087
0.1038
0.1081
0.1012
0.1134
0.1257
0.1193
Total Crc
results by
NAA, Mg
85.3
69.6
74.0
208.1
88.7
190.9
61.1
74.6
96.1
93.1
166.4
56.4
67.9
65.0
72.3
40.0
75.7
85.6
81.5
54.9
Total Crd
concen-
tration
by NAA.
W9/9
861
657
675
5,564
2,807
7,545
635
730
2,219
2,299
447
441
693
598
697
370
748
755
648
460
Total Cre
content of
emission
sample,
v9
18,243
4,645
4,623
208.1
88.7
190.9
883'
330
141
139
166.4
56.4
67.9
65.0
72.3
40.0
75.7-
85.6
81.5
54.9
Total Cr
concentration,
wg/dNm3
2.695
1,836
2,010
27.3
11.6
25.0
833
311
133
131
157
-
-
- '
gr/dscf
0.001
0.0008
0.0009
0.00001
0.000005
0.00001
0.0004
0.0001
0.00006
0.00006
0.00007
-
-
-
Total Cr mass
emission rate.
kg/h
0.55
0.40
0.41
0.005
0.002
0.005
0.22
0.06
0.03
0.03
0.03
-
-
-
Ib/h
1.04
0.90
0.92
0.01
0.005
0.01
0.40
0.14
0.06
0.06
0.07
-
-
-
(continued)
-------
TABLE 2-7 (continued)
ro
I
ro
ro
Run
No.
PCI
and
PCO-3
Sample type
and location
ESP - Fly ash - Field 1
ESP - Fly ash - Field 2
ESP - Fly ash - Field 3
ESP - Fly ash - Field 4
Total3
participate
collected,
9
i
Participate
sample weight
analyzed by
NAA, g
0.1066
0.0923
0.0989
0.1238
Total Crc
results by
NAA, ug
80.8
70.5
55.6
32.9
Total Crd
concen-
tration
by NAA,
W9/9
758
764
562
266
Total Cre
content of
emission
sample,
ug
80.8
70.5
55.6
32.9
Total Cr
concentration.
ug/dNm3
-
gr/dscf
-
Total Cr mass
emission rate,
kg/h
-
Ib/h
-
aTotal particulate (acetone rinse residue and filter) collected during sample run.
Particulate weight analyzed by MM.
cTotal Cr results by NAA. Run No. PCO/T (ESP outlet) is a blank corrected value (=15 ug Cr for filter/acetone blank).
tide size thimble (backup) values have been blank corrected for =44 yg Cr.
dTotal Cr(C) divided by particulate weight analyzed by NAA(b).
eTotal Cr concentration (vg/g) multiplied by total particulate weight collected(a).
Par-
-------
The backup thimble (less than 2.4 ym) showed 166 yg total Cr. This
figure has been blank corrected by 44 yg to account for the background levels
of Cr in the thimble filter. On a concentration basis, Stage 1 (13.0 ym cut
point) was 311 yg/dNm3, Stage 2 (6.9 ym cut point) was 133 yg/dNm3, Stage 3
(2.4 ym cut point) was 131 yg/dNm3, and the backup stage (less than 2.4 ym)
was 157 yg/dNm3. These data indicate a fairly uniform distribution of total
Cr of less than 13 ym in diameter.
The composite fly ash/bottom ash sample showed 441 yg/g total Cr. ESP
fly ash samples showed total Cr concentrations ranging between 266 and 764
yg/g. It should be noted that EPA attempted to quantify Ni and Cd by NAA.
All samples showed nondetectable levels of Ni, and only one process sample
(ESP fly ash) showed any Cd at a level of 301 yg/g.
Table 2-8 is a summary of Be, Pb, and Zn concentration data. Single
composite samples of incinerator bottom ash and ESP fly ash from each test
period were analyzed using ICAP techniques. Sample preparation procedures
generally followed those described in EPA Method 3050 of SW-846.* This
analysis was performed in July 1986.
Test Methods for Evaluating Solid Waste. U.S. EPA SW-846, 2nd ed, July
1982, Method 3050.
2-23
-------
TABLE 2-8. SUMMARY OF BERYLLIUM, LEAD, AND ZINC ANALYTICAL DATA
Sample type
Bottom ash
ESP fly ash, Field No. 4
Test No.
1
2
3
1
2
3
Laboratory
No.
EL 143
EL 144
EL 145
EL 155
EL 156
EL 157
Concentration, yg/g
(as received)
Be
<0.07
<0.07
<0.07
<0.07
<0.07
<0.07
Pb
1,450
1,640
1,500
10,825
2,820
7,608
Zn
5,260
5,940
4,790
82,600
91,200
97,200
2-24
-------
SECTION 3
PROJECT QUALITY ASSURANCE
The application of quality assurance procedures to source emission
measurements ensures accurate emission-testing results. Quality assurance
guidelines provide the detailed procedures and actions necessary for defining
and producing acceptable data. In this project, five documents were used in
the preparation of a source-specific test plan that would ensure the collec-
tion of acceptable data: 1) the EPA Quality Assurance Handbook Volume II,
EPA-600/4-77-0271; 2) the PEI Emission Test Quality Assurance Plan; 3) the
PEI Laboratory Quality Assurance Plan; 4) Determination of Hexavalent Chromi-
um Emissions From Stationary Sources, December 13, 1984; and 5) EPA Protocol
for Emissions Sampling for Both Hexavalent and Total Chromium, February 22,
1985. Two of these are PEI's general guideline manuals and define the com-
pany's standard operating procedures followed by the company's emission
testing and laboratory groups.
In this specific test program, which was reviewed by EPA's Emission
Measurement Branch, the following steps were taken to ensure that the testing
and analytical procedures produced quality data:
0 A sample of the combination bottom ash-ESP fly ash yas obtained
during the April pretest survey and analyzed for Cr 6 content.
These data were used to Define sampling times and rates so that a
quantifiable level of Cr 6 was collected.
0 Calibration of all field sampling equipment.
0 Checks of train configuration and calculations.
3-1
-------
0 Onsite quality assurance checks, such as leak checks of the sam-
pling train, pitot tube, and Orsat line and onsite quality assur-
ance checks of all test equipment prior to use.
0 Use of designated analytical equipment and sampling reagents.
0 Internal and external audits to ensure accuracy in sampling and
analysis.
Table 3-1 lists the specific sampling equipment used to perform the
particulate/Cr , particle size distribution, and arsenic tests as well as
the calibration guidelines and limits. In addition to the pre- and post-test
calibrations, a field audit was performed on the metering systems and temper-
ature-measurement devices used during sampling. These data are summarized in
Table 3-1, and copies of the field audit data sheets are presented in Appen-
dix B of this report.
The PEI project manager performed the onsite sample calculations, and
computer programming was used to validate the data upon return to PEI's
Cincinnati laboratory. Minor discrepancies between the hand calculations and
computer printouts are due primarily to rounding off of values. Computerized
example calculations are presented in Appendix A.
The following subsections summarize the quality assurance activities
performed during the analytical phase of this project. As a check of the
gravimetric analytical procedure, blank filter and reagent (acetone) were
analyzed in a fashion similar to that used for the actual field samples.
Table 3-2 summarizes the blank analysis data. These data indicate good
analytical technique.
Emission and process samples were analyzed in four separate batches.
Table 3-3 summarizes the linear regression data of the spectrophotometer
calibration for the four days.
The detection limit established for the four days was less than 0.004
pg/ml for an absorbance of 0.005 above the linear regression intercept.
3-2
-------
TABLE 3-1. FIELD EQUIPMENT CALIBRATION
Equipment
Meter box
Pi tot tube
Digital Indicator
Thermocouple
and stack
thermometer
Orsat analyzer
Impinger
thermometer
Trip balance
Barometer
Dry gas
thermometer
Probe nozzle
ID
No.
FB-3
FB-8
FB-11
FB-12
187
522
220
262
104
257
141
1-1
1-5
Mettler
No. 743985
227
FB-3
FB-8
FB-11
FB-12
5-108
5-105
3-111
A-l
Calibrated
against
Wet test meter
Standard pilot
tube
Millivolt signals
ASTM-3F
Standard gas
ASTM-3F
Type S weights
NBS traceable
barometer
ASTM-3F
Calf per
Allowable
error
AHP ±0.15
(Y ±0.5% Y post-test)
Cp ±0.01
0.5%
1.5*
(±2% saturated)
±0.5%
±2°F
tO. 5 g
±0.10 in.Hg
(0.20 post-test)
±5°F
On ±0.004 In.
Actual
error
4H0: +0.02; Y: 0.7%
4H@: -0.06; Y: -1.0%
AH0: -0.04; Y: -1.3%
AHP: 0 Y: + 1.7%
0
0
-0.45*
+0.41%
+0.38%
+0.19%
+0.2% (0,)
-0.2% (C02)
+1°F
+1°F
<0.1 g
0.01
In: +2°F; Out: +2°F
In: +4°F: Out: +3°F
In: +1°F; Out: +4°F
In: +1"F; Out: 0°F
0.001
0.004
0.00
0.001
Within
allowable
limits
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Comments
Y •= 0.986; Audit AH0 = 1.86
Y = 1.006; Audit AHP = 1.90
Y •= 1.058; Audit AH@ = 1.20
Y = 0.954; Audit AHP = 1.07
(Field audit results)
From Geometric Spec.
40 CFR Appendix A; Reference Method 2
(0.84 coefficient assumed)
Maximum deviation
Maximum deviation
Audit value
02 and CO., * 5.0%
Maximum deviation
Maximum deviations
Maximum deviations
Maximum deviations
Maximum deviations
u>
co
-------
TABLE 3-2. EXAMPLE FILTER AND REAGENT BLANK
ANALYSIS FOR PARTICIPATE
Sample type and
filter number
Participate - 8510128
Reeve Angel 934 AH
Acetone blank3
Water blank
Original tare
weight, mg
363.8
99530.6
NAC
Blank
weight, mg
364.2
99534.1
NA
Net
weight, mg
0.4
3.5 mgb
(0.032 mg/g)
NA
137 ml evaporated and desiccated before weighing.
DMethod 5 and particle size acetone blank (0.01 mg/g used in calculations).
CNA = Not applicable.
3-4
-------
TABLE 3-3. LINEAR REGRESSION DATA SPECTROPHOTOMETER CALIBRATION
Sample
description
Process sam-
ples
PCI-3
PCI-1
PCI-1 +
spike
PCI-2
PCI-3 +
duplicate
Date
(1985)
5/22
6/5
6/11
6/12
Cr+6
standard
concen-
tration,
yg/ml
0.0
0.1
0.2
0.3
0.4
0.5
0.0
0.1
0.2
0.3
0.4
0.5
0.0
0.1
0.2
0.3
0.4
0.5
0.0
0.1
0.2
0.3
0.4
0.5
Absorb-
ance
0.000
0.136
0.267
0.403
0.537
0.656
0.000
0.130
0.262
0.390
0.522
0.656
0.000
0.130
0.262
0.386
0.513
0.632
0.000
0.128
0.263
0.401
0.532
0.663
Y-Intercept
0.0032
0.0008
0.0039
-0.0020
Slope
1.3197
1.3097
1.2666
1.3329
Correlation
coefficient
0.99982
0.99998
0.99986
0.99995
3-5
-------
Because the concentration of hexavalent chromium in these solid samples
were extremely low, the amount of alkaline extraction solution and the final
dilution volume of this extract were kept at a minimum consistent with Method
3060 from Test Methods for Evaluating Solid Waste.* This proportion is 4 ml
of alkaline extraction solution per gram of solid diluted to a final volume
of 10.ml.
All reagent blanks were less than the detection limit. No other blanks
were necessary because all analyses were performed on loose particulate;
i.e., no filter or thimbles were extracted. Duplicate analysis (extraction
and colorimetric determination) was performed on the inlet particulate of Run
3. Also, the inlet particulate from Run 1 was checked by method of addition.
The results for these samples are presented in Table 3-4.
TABLE 3-4. RESULTS OF QC SAMPLES
Sample
Particulate Run 3
Particulate Run 1
QC type
Duplicate
Spike
Results
0.15, <0.1 yg/g
94% recovery
One problem was encountered with the analysis of the inlet particulate
samples and the composite bottom ash samples. After the alkaline extract was
filtered, the samples were slightly cloudy (white opaqueness). This inter-
fered with the colorimetric determination and the absorbance of an aliquot
not containing the color reagent was subtracted from the absorbance of the
sample to correct for this interferent.
Arsenic samples were analyzed on June 4, 1985. The least square fit of
the data to quadratic equations for the graphite furnace atomic absorption
calibration gave a correlation coefficient of 0.9990. The results of blank
analyses were 8.56 pg for the filter and <0.006 mg/liter (detection limit)
3-6
-------
for the rinse and impinger samples. The filter blank value is typical for
glass fiber filters. Duplicate analysis of the bomb fraction and rinse
fraction for the outlet runs gave 3.26, 4.48, 4.91, and 4.61 yg, respec-
tively. Spike recoveries were 95.4, 92.1, 101.9, and 0 percent for the
filter, rinse, impingers, and bomb fractions, respectively.
Table 3-5 presents QC data relative to the total Cr analysis by NAA.
Duplicate, audit, and blank data are presented.
TABLE 3-5. QC DATA FOR TOTAL CHROMIUM BY NAA
Sample test type
Test No. PCI-1 (acetone
residue/particulate sample)
NBS coal fly ash
NBS fly ash
Alkaline extract
Type I H20
Method 5 filter/acetone
Particle size thimble - backup
Analysis
Duplicate analysis
Audit
Audit
Blank
Blank
Blank
Blank
Results total Cr
85.3/106.9 yg
182.8 yg/g (196 yg/g
accepted)
32.2 yg/g (34.4 yg/g
accepted)
Not detected
Not detected
15.0 yg
44.0 yg
3-7
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SECTION 4
SAMPLING LOCATIONS AND TEST PROCEDURES
This section describes the sampling sites and the test methods used to
characterize participate and chromium emissions from Incinerator No. 2.
4.1 SAMPLING LOCATION
Flue gas samples were extracted from existing sampling ports prior to
and after the ESP that controls particulate emissions from Incinerator No. 2.
Figures 4-1 and 4-2 show the test locations.
At the ESP inlet, five 10-cm (4-in.) i.d. sampling ports were located
approximately 2.9 equivalent duct diameters (EDO) downstream and 2 EDO up-
stream from the nearest flow disturbances in a rectangular duct with an i.d.
of 2.1 x 3.7 m (6.75 x 12 ft). At the ESP outlet, six 10-cm (4-in.) i.d.
sampling ports were located approximately 4.2 EDO downstream and 0.8 EDO
upstream of the nearest flow disturbances in a rectangular duct with an i.d.
of 3.1 x 2.0 m (10 ft 2i in. x 6 ft 5i in.). Both locations conformed to the
minimum requirements for sampling port locations specified in EPA Reference
Method 1.*
4.2 PARTICULATE AND HEXAVALENT CHROMIUM SAMPLE EXTRACTION AND ANALYSIS
Flue gas samples were simultaneously collected at the ESP inlet and
outlet test locations according to procedures outlined in EPA Reference
Method 5.**
40 CFR 60, Appendix A, Reference Method 1, July 1984.
40 CFR 60, Appendix A, Reference Method 5, July 1894.
4-1
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TO ESP/
/
TO ESP/
o M8m(]ft) |
t GAS FLOW ° "f'V") , fUW
" 1
5.2 m t 7.6m -1 » O ft) I
HEAT RECOVERY
BOILER
\
(17ft> (25ft) J_ F3x» LEVEL
ELEVATION
< ^ mn ft\ DUST ASPIRATION
3 .3^mU ft) ^.SYSTEM
*** >/ (DAMPER CLOSED
DURING TESTING)
n
i
*GASFLOW 37mM-ft)
\ '
\ 1
5.2m ,, 7.6m
(17ft) (25ft)
HEAT RECOVERY
BOILER
TOP VIEH
Figure 4-1. No. 2 incinerator ESP inlet sampling location (no scale)
4-2
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90° BEND
FROM ESP GAS
CO
FLOW
CROSS-SECTION
*10m
( 33ft)
m
(10 ft)
.508 m(l ft 8 in.)
m
(10 ft 2/2 1n«)
»2.0 m
(6 ft.S1^ in.)
\
U U D LJ LJ U
6-10 cm(4 in.)
i.d. SAMPLE PORTS
*PORT INACCESSIBLE
I |(NOT SAMPLED)
o o o o
r—
o o
PORT INACCESSIBLE(NOT SAMPLED)
1.8 m (6 ft)
Figure 4-2. No. 2 incinerator ESP outlet sampling location (no scale).
-------
Initially, the collected samples were analyzed gravimetrically by Method
5 to determine participate concentration and mass emission rates. At the
completion of the gravimetric analysis, the inlet samples were prepared and
analyzed for Cr according to procedures described in a draft EPA method en-
titled "Determination of Hexavalent Chromium Emissions From Stationary
Sources." A copy of the draft method is contained in Appendix H of this
report.
Before sampling began, velocity, static pressure, molecular weight,
moisture content, and temperature were measured to define sampling rates and
nozzle sizes are described in EPA Reference Methods 1 through 4.* The degree
of turbulent flow at each location also was assessed according to procedures
described in EPA Reference Method 2.* In this method, the face opening of
the Type-S pitot tube is aligned perpendicularly to the duct cross-sectional
plane, designated "0-degree reference." Null (zero) pitot readings obtained
at a 0-degree reference indicate an acceptable flow condition at a given
point.
If the pitot reading is not zero at 0-degree reference, the pitot is
rotated (up to 90 degrees ± yaw angle) until a null reading is obtained. The
value of the rotation angle (yaw) is recorded for each point and averaged
across the duct. Method 2 criteria stipulate that average angular rotations
greater than ± 10 degrees indicate turbulent (nonaxial) flow conditions in
the duct(s). This procedure was used to check several traverse points at
each location. In each case, null pitot readings were observed at the 0-
degree reference. These data, together with the velocity and temperature
profiles established for each location, indicated acceptable flow patterns
that would enable the extraction of representative samples at each site.
40 CFR 60, Appendix A, Reference Methods 1 through 4, July 1984.
4-4
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At the ESP inlet, a 5 x 5 sampling matrix, or 25 total sampling points,
were used to traverse the cross-sectional area of the duct. Sampling ports
located on each side of the ductwork (see Figure 4-1) were used to complete
the traverse. Each point was sampled for 12 minutes, yielding a total test
time of 300 minutes per test.
At the ESP outlet, a 5 x 5 sampling matrix was established and 25 total
sampling points were used to traverse the duct cross-section. Each point was
sampled for 12 minutes, yielding a total test time of 300 minutes. It should
be noted that one of the six available sampling ports was not sampled due to
the close proximity of an I-beam which prevented insertion of the sample
probe for this port. Due to the low grain loading and size distribution
results at this site, biases in particulate measurements are believed to be
insignificant.
The test and analytical procedures used are described briefly here, and
detailed procedures are presented in Appendix D.
4.2.1 Velocity and Gas Temperature
A Type-S pi tot tube and an inclined draft gauge manometer were used to
measure the gas velocity pressures at the test sites. Velocity pressures
were measured at each sampling point across the duct to determine an average
value. Measurements were taken in the manner prescribed in EPA Reference
Method 2.* The temperature at each sampling point was measured with a ther-
mocouple and digital readout.
4.2.2 Molecular Weight
Flue gas composition was determined in accordance with the basic proce-
dures described in EPA Reference Method 3.* Grab samples were collected
40 CFR 60, Appendix A, Reference Methods 2 and 3, July 1984.
4-5
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prior to the start of any sampling to establish baseline contents of oxygen,
carbon dioxide, and carbon monoxide. Integrated bag samples were collected
during each test and were analyzed with an Orsat gas analyzer. The gas
composition at each test site remained consistent throughout the test series.
4.2.3 Particu1ate/Cr+6
Particulate and Cr samples were collected as specified in EPA Refer-
ence Method 5.* All tests were conducted isokinetically by regulating the
sample flow rate relative to the gas velocity in the duct (as measured by the
pitot tube and thermocouple attached to the sample). The basic sampling
train consisted of a heated glass-lined probe, a heated 7.6-cm (3-in.) diam-
eter glass-fiber filter (Whatman Reeve Angel 934 AH), and a series of five
Greenburg-Smith impingers followed by a vacuum line, vacuum gauge, leak-free
vacuum pump, dry gas meter, thermometers, and a calibrated orifice.
For determination of particulate concentration, the nozzle, probe, and
filter holder portions were rinsed with acetone at the end of each applicable
test. The acetone rinse and particulate caught on the filter media were
dried at room temperature, desiccated to a constant weight, and weighed on an
analytical balance. Total filterable particulate matter was determined by
adding these two values.
Upon completion of the gravimetric analysis, the inlet sample fractions
were prepared and analyzed for Cr according to procedures recently devel-
oped by EPA. In summary, the samples were digested in an alkaline solution
and analyzed by the diphenylcarbazide colorimetric method.**
40 CFR 60, Appendix A, Reference Method 5, July 1984.
**
Test Methods for Evaluating Solid Waste. U.S. Environmental Protection
Agency, SW-846, 2nd ed., July 1982.
4-6
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The volume of water collected in the impinger section of the sampling
train(s) was measured at the end of each sample run to determine the moisture
content of the flue gas. The contents of the impingers were transferred to a
polyethylene container. The impingers and all connecting glassware, includ-
ing the back half of the filter holder, were rinsed with distilled water and
the rinse was added to the container.
4.3 PARTICLE SIZE DISTRIBUTION
Samples for particle-size distribution measurements were collected at
the ESP inlet and outlet by the use of two different configurations of in-
stack cascade impactors. The Andersen Mark III multistage impactor was used
at the ESP outlet and the Andersen Heavy Grain Loading Impactor (HGLI) was
used at the ESP inlet.
The Andersen Mark III in-stack impactor consists of eight size cut-point
stages and a backup filter.
This impactor was assembled by alternating the stage plates, collection
media, flat crossbars, and Inconel spacer rings needed to provide weight cut
sizes. The collection substrates were Reeve Angel 934 AH glass-fiber filters
that have been heated in a 204°C (400°F) oven for 1 or 2 hours, desiccated
for 24 hours to a constant weight, and weighed to the nearest 0.1 mg on an
analytical balance. A total of three samples were collected at a single
point representing the average velocity and temperature in the outlet duct.
Sample times ranged from 210 to 300 minutes. Isokinetic sampling rates were
set initially and constant cut-point characteristics were maintained through-
out the sampling period.
Each size fraction was subjected to a gravimetric analysis using EPA
Method 5 procedures.
4-7
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For each test, size distribution curves were established representing
the total weight percent of particulate matter smaller than the indicated
aerodynamic particle diameter in micrometers.
Cut-points for the eight Mark III impactor stages were calculated by
computer programs contained in "A Computer-Based Cascade Impactor Data Reduc-
tion System" (CIDRS) developed for EPA by Southern Research Institute (SRI).*
All particle size results are based on a particle density of 1 g/cm3. Data
reduction and intermediate results calculations for both types of impactors
were performed by the CIDRS program, with moisture contents obtained from the
particulate tests.
The Andersen HGLI used at the ESP inlet consists of two single-jet
impaction chambers followed by a third-stage cyclone and a backup filter.
The sampled gas stream enters the system through the Stage 1 acceleration
jet. Particles with sufficient inertia are impacted against the bottom of
the Stage 1 impaction chamber. Smaller particles flow with the gas stream
and exit the impaction chamber through three vent tubes.
Stage 2 of the HGLI is simply a scaled-down version of Stage 1 in which
the jet nozzle diameter and the distance from jet exit to impaction surface
have been designed for the proper Stage 2 cut-point.
Stage 3 of the HGLI is a small cyclone of the Southern Research Insti-
tute design. A high-efficiency glass-fiber filter removes all particles
remaining in the gas stream downstream of the cyclone.
The Andersen HGLI was used at the inlet because of expected heavy par-
ticulate concentration, which would overload a standard multistage impactor.
Three samples were collected at the ESP inlet from a single point in the duct
*
Southern Research Institute. A Computer-Based Cascade Impactor Data Reduc-
tion System. Prepared for U.S. Environmental Protection Agency under Con-
tract No. 68-022-131, March 1978.
4-8
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that was representative of the average velocity and temperature. Sample
times ranged from 90 to 120 minutes.
At the completion of each test, the impactor samples were recovered in
accordance with procedures described in the HGLI operation manuals.
Each recovered fraction was then subjected to a gravimetric analysis in
accordance with EPA Reference Method 5 criteria. Size distribution curves
representing the total weight percent of particulate matter smaller than the
indicated aerodynamic particle diameter (in micrometers) were established for
each run.
The three cut-points for each Andersen HGLI test were determined graphi-
cally from information supplied by the manufacturer. All particle size
results are based on a particle density of 1 g/cm3. Data reduction and
intermediate result calculations were performed by CIDRS programs with mois-
ture contents and gas composition data obtained from the particulate/Cr
tests.*
4.4 PROCESS SAMPLES
During the particulate/chromium tests, the following process samples
were collected:
0 Composite fly ash/incinerator bottom ash
0 No. 2 ESP fly ash samples from each of 4 fields
Grab samples of the composite bottom ash were collected every 60 to 90
minutes or four to six times during a 6-hour test run. This nonhomogeneous
material represents an overall composite of the bottom ash and ESP fly ash
from each incinerator. The material was collected from a vibrating screen
*Southern Research Institute. A Computer-Based Cascade Impactor Data Reduc-
tion System. Prepared for U.S. Environmental Protection Agency under Con-
tract No. 68-022-131. March 1978.
4-9
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prior to loading into trucks for disposal in a landfill. The samples from
each test were composited using a morter and pestal and centrifuging so that
one representative sample of each sample type per test was available for
analysis. Solid samples were extracted and analyzed for Cr in accordance
with procedures similar to those used for the Cr analysis of the particu-
late samples. ESP fly ash samples were collected in a similar manner as the
bottom ash samples except separate samples from each of four ESP electrical
fields were collected. For the three tests, 12 samples were collected. All
samples were collected sequentially from the B side fly ash hopper. Only the
No. 4 field samples were analyzed for Cr for each test day. Analytical
procedures followed those used for the bottom ash samples. The analyses of
the incinerator bottom ash and ESP fly ash were relatively straightforward
and no problems were encountered.
Process samples (as designated in Subsection 2.6) were shipped to EPA
and analyzed for total Cr, Ni, and Cd using NAA. PEI later analyzed these
samples for Be, Pb, and Zn using ICAP.
4.5 ARSENIC
Arsenic concentrations were measured by EPA Reference Method 108.* All
tests were conducted isokinetically by regulating the sample flow rate to
correspond to the gas velocity in the duct (as measured by the pitot tube and
thermocouple attached to the sample probe). The basic sampling train con-
sisted of a heated glass-lined probe, a heated 7.6-cm (3-in.) diameter glass-
fiber filter (Whatman Reeve Angel 934 AH), and a series of five Greenburg-
Smith impingers followed by a vacuum line, vacuum gauge, leak-free vacuum
pump, dry gas meter, thermometers, and a calibrated orifice.
40 CFR 61, Appendix B, Reference Method 108, July 1984.
4-10
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For determination of arsenic concentrations, the nozzle, probe, and
filter holder portions were rinsed with 0.1 N NaOH at the end of each appli-
cable test.
The filter and solids contained in the 0.1 N NaOH rinse of the front
half of the sampling train were prepped, combined, and analyzed for arsenic
(by atomic absorption).
The volume of water collected in the impinger section of the sampling
train was measured at the end of each sampling run to determine the moisture
content of the flue gas. The contents of the impingers were transferred to a
polyethylene container. The impingers and all connecting glassware (includ-
ing the back half of the filter holder) were rinsed with 0.1 N NaOH, and the
rinse was added to the container. The contents of the impingers and 0.1 N
NaOH rinse also were analyzed for arsenic by atomic absorption.
4-11
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SECTION 5
PROCESS DESCRIPTION*
Tests were conducted on the exhaust gases of the reciprocating grate
Incinerator No. 2 at the Baltimore RESCO refuse-to-energy plant. Figure 5-1
presents an exhaust gas flow schematic with sampling locations. The Balti-
more RESCO refuse-to-energy plant was designed and constructed by Signal
Environmental Systems, Inc., (SES) to provide for the disposal of up to 2250
tons per day of municipal solid waste from the City and County of Baltimore,
Maryland. SES also operates and maintains the facility.
The facility has three identical reciprocating grate incinerators. Each
incinerator has a rated capacity of 750 tons/day and typically incinerates
600 tons of waste per day, 24 hours per day, 7 days a week. Natural gas is
used as an auxiliary fuel. Each incinerator has its own heat recovery boiler
capable of producing 170,000 pounds of steam per hour at 850 psig and 825°F.
The electric power capacity of the turbogenerators is 55 megawatts; the
Baltimore Gas and Electric Company is the primary customer.
Each incinerator has an ESP to control particulate emissions. ESP
emissions are routed to a common stack. The ash handling system for both the
incinerator and ESP is the vibrating fan conveyor type. Ash from each system
is transferred to a common ash pit for separation of ferrous and aggregate
materials. After separation, the ash is transported to a landfill.
Prepared by Midwest Research Institute.
5-1
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SOLID
WASTE
HEAT RECOVERY
BOILER -
INCINERATOR
NO. 2
INCINERATOR
BOTTOM ASH
TO COMMON STACK
AND ATMOSPHERE
I.D.
FAN
OUTLET TEST P|
LOCATION LJ
INLET TEST
LOCATION
O
ESP HOPPER
COMMON
ASH PIT
FLY ASH
ELECTROSTATIC
PRECIPITATOR
T
TO LANDFILL
Figure 5-1. No. 2 incinerator exhaust gas flow schematic.
5-2
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