United States
Environmental Protection
Agency
EPA-600/7-86-014a
April 1986
Research and
Development
ENVIRONMENTAL ASSESSMENT OF
A RECIPROCATING ENGINE
RETROFITTED WITH
SELECTIVE CATALYTIC REDUCTION
Volume I. Technical Results
Prepared for
Office of Air Quality Planning and Standards
Prepared by
Air and Energy Engineering Research
Laboratory
Research Triangle Park NC 27711
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide range of energy-related environ-
mental issues.
EPA REVIEW NOTICE
This report has been reviewed by the participating Federal Agencies, and approved
for publication. Approval does not signify that the contents necessarily reflect
the views and policies of the Government, nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service. Springfield. Virginia 22161.
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EPA-600/7-86-014a
April 1986
ENVIRONMENTAL ASSESSMENT OF A RECIPROCATING ENGINE
RETROFITTED WITH SELECTIVE CATALYTIC REDUCTION
Volume I: Technical Results
by
Carlo Castaldini and Larry R. Waterland
Acurex Corporation
555 Clyde Avenue
P.O. Box 7555
Mountain View, California 94039
EPA Contract 68-02-3188
EPA Project Officer: J. A. McSorley
Air and Energy Engineering Research Laboratory
Research Triangle Park, North Carolina 27711
for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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ABSTRACT
Comprehensive emission measurements and 15-day continuous emis-
sion monitoring was performed for a 1, 500 kW (2000 hp) gas-fired, four-
stroke turbocharged reciprocating engine equipped with an ammonia-based
selective catalytic reduction system for NOX control. Emission reductions
were held at about 80 percent using an ammonia-to-NO ratio of about 1.0.
NOX levels at the catalyst inlet ranged from 2,200 to 2,600 ppm at an exhaust
gas oxygen level of about 11 percent. NOX levels at the catalyst outlet ranged
between 65 and 120 ppm. The catalyst had relatively minor effect on CO and
particulate emissions, but increased total cyanides by three orders of magni-
tude (from 7 jug/dscm to 2.4 mg/dscm) across the catalyst. Total organics
decreased about 70 percent from 4.9 mg/dscm to 1. 5 mg/dscm. Analyses
showed benzene and toluene as the major organic constituents in the cata-
lyst exhaust. Polycyclic aromatics also decreased across the catalyst. The
15-day continuous monitoring tests showed that the catalyst was generally
able to maintain NOX reductions at about 80 percent. Departures from these
levels occurred only during brief load surges and ammonia flowrate spikes.
11
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CONTENTS
Section Page
Figures iv
Tables v
1 Introduction 1-1
2 Source Description and Operation 2-1
3 Emission Results 3-1
3.1 Sampling Protocol 3-1
3.2 Criteria Pollutant and Other Vapor Species
Emissions 3-3
3.3 Organic Species Emissions 3-9
3.4 Extended Continuous Emission Monitoring 3-15
4 Quality Assurance Activities 4-1
4.1 NOX Certification Results 4-1
4.2 Spiked XAD-2 Resin Analysis 4-2
4.3 Ammonia Spike Sample Analysis 4-2
4.4 Duplicate Organic Analysis of XAD-2 Extract .... 4-4
5 Summary 5-1
Appendix A A-l
111
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FIGURES
Number Page
3-1 Sampling sites and analysis test matrix .... ..... 3-2
3-2 Test activity schedule ................. 3-4
3-3 Exhaust $2 and ^2 ^or the extended continuous
monitoring period .................... 3-17
3-4 Exhaust NOX levels for the extended continuous
monitoring period .................... 3-18
3-5 Catalyst NOX reduction efficiency for the extended
monitoring period .................... 3-19
3-6 Catalyst outlet NH^ emissions for the extended
continuous monitoring period .............. 3-20
3-7 Exhaust CO levels for the extended continuous
monitoring period .................... 3-21
3-8 Exhaust hydrocarbon levels for the extended continuous
monitoring period .................... 3-22
iv
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TABLES
Number
1-1 Completed Tests During the Current Program 1-5
2-1 Engine/Compressor Specification .... 2-2
2-2 Engine Operation 2-4
2-3 Natural Gas Fuel Analysis 2-5
3-1 Criteria and other Gas Phase Species Emissions:
Comprehensive Tests 3-5
3-2 Ammonia Measurements, PPM Dry as Measured 3-7
3-3 N20 Emissions: 1C Engine/SCR Tests 3-9
3-4 Compounds Sought in the GC/MS and Their Detection
Limits (ng/ul Injected) 3-11
3-5 Volatile Organics Sought in GC/MS Analysis 3-12
3-6 Total Organic and Semi volatile Organic Priority
Pollutant Emissions: 1C Engine/SCR System Tests,
XAD-2 Plus OMC Extract 3-13
3-7 IR Spectra Summary 3-14
3-8 Volatile Organic Sampling Train Results: Catalyst
Outlet 3-16
4-1 XAD-2 Resin Spike and Recovery Results 4-3
4-2 Duplicate GC/MS Analysis Results for the Catalyst
Outlet XAD-2 Extract 4-4
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ACKNOWLEDGEMENTS
This test was performed in cooperation with Southern California Gas
Company (SoCal). Much appreciation is extended to G. Gardetta and
E. Harris of SoCal. Special recognition and thanks are extended to the
Acurex field test crew of C. Milburn, M. Murray, V. Barkus, and P. Kaufmann.
VI
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SECTION 1
INTRODUCTION
This report describes and presents results for a set of environmental
assessment tests performed for the Industrial Environmental Research
Laboratory/Research Triangle Park (IERL/RTP) of EPA under the Combustion
Modification Environmental Assessment (CMEA) program, EPA Contract
No. 68-02-3188. The CMEA started in 1976 with a 3-year study, the NOX
Control Technology Environmental Assessment (NOX EA, EPA Contract
No. 68-02-2160), having the following objectives:
Identify potential multimedia environmental effects of stationary
combustion sources and combustion modification technology
Develop and document control application guidelines to minimize
these effects
Identify stationary source and combustion modification R&D
priorities
Disseminate program results to intended users
During the first year of the NOX EA, data and methodologies for the
environmental assessment were compiled. Furthermore, priorities for the
schedule and level of effort for developing emission data for the various
source/fuel/control combinations were identified. This effort revealed major
data gaps, particularly for noncriteria pollutants (organic emissions and
trace elements) for virtually all combinations of stationary combustion
1-1
-------
sources and combustion modification techniques. Consequently, a series of
seven environmental field test programs was undertaken to fill these data
gaps. The results of these tests are documented in seven individual reports
(References 1-1 through 1-7) and in the NOX EA final report summarizing the
entire 3-year effort (Reference 1-8).
The current CMEA program has, as major objectives, the continuation of
multimedia environmental field tests initiated in the original NOX EA
program. These new tests, using standardized sampling and analytical
procedures (Reference 1-9) are aimed at filling remaining data gaps and
addressing the following priority needs:
Advanced NOX controls
Alternate fuels
Secondary sources
EPA program data needs
Residential oil combustion
Wood firing in residential, commercial, and industrial sources
High interest emissions determination (e.g., listed and
candidate hazardous air-pollutant species)
Nonsteady-state operations
In California, the South Coast Air Quality Management District (SCAQMD)
continues to be in nonattainment of both federal and state N02 standards.
Reciprocating internal combustion engines (ICE's) in this district are
estimated to contribute 14 percent of the NOX (about 59 Mg/day (65 tons/day))
from all stationary sources and 5.1 percent of the total NOX emissions in the
basin (References 1-10 and 1-11). Furthermore, since acid precipitation in
noncoal-burning regions such as the SCAQMD is being increasingly attributed
1-2
-------
to NOX emissions from sources with low stacks, reciprocating ICE's are being
viewed as possibly contributing to the acid rain problem.
In 1979, the California Air Resources Board (CARS) proposed a control
strategy for ICE's that called for retrofit of these sources with selective
and nonselective treatment catalysts (SCR and NSCR, respectively). In
keeping with this CARB strategy, the SCAQMD passed rule 1110 calling for
demonstration tests of SCR and NSCR technologies for engine NOX control.
Southern California Gas Company (SoCal) has conducted several performance
tests to evaluate SCR and NSCR catalysts for their applicability in reducing
NOX from SoCal operated ICE's. However, data on sustained NOX reduction
performance associated with these technologies are currently limited
(Reference 1-12). In addition, some potential environmental concerns have
been raised. In the case of SCR, for example, the breakthrough of ammonia
from the catalyst has been highlighted. For NSCR, the formation of ammonia
and cyanide gases are also concerns.
In response to these data requirements and environmental concerns, a
lean-burn reciprocating ICE operated by SoCal and retrofitted with a
commercially available SCR system was selected for testing under the CMEA
program. The objective of the tests was to quantify multimedia emissions
(including organics, ammonia, and N£0) at the inlet and outlet of the SCR
catalytic reactor. In addition ito these tests, NOX reduction performance of
the SCR was monitored continuously over 15 days under typical operating
conditions,. A similar field test program was conducted on a rich-burn engine
retrofitted with a NSCR reactor. The results of these tests are documented
in a separate report (Reference 1-13).
1-3
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Table 1-1 lists all the tests performed in the CMEA program, outlining
the source tested, fuel used, combustion modifications implemented and the
level of sampling and analysis performed in each case. Results of these test
programs are discussed in separate reports.
1-4
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TABLE 1-1. COMPLETED TESTS DURING THE CURRENT PROGRAM
Source
Description
Test points
unit operation
Sampling protocol
Test collaborator
Spark-Ignited, natural-
gas-fueled reciprocating
Internal combustion
engine
Large-bore, 6-cyllnder,
opposed piston, 186 kH
(250 BhpJ/cyl, 900 rpm,
Model 38TOS8-1/8
Baseline (pre-NSPS)
Increased air-fuel
ratio aimed at
meeting proposed
NSPS of 700 ppm
corrected to 15
percent 02 and
standard atmospheric
conditions
Engine exhaust:
SASS
~ Method 5
Gas sample (C^-Cg HO
Continuous NO, NOX, CO,
C02. 02, CH4, TUHC
Fuel
Lube oil
Fairbanks Morse
Division of Colt
Industries
i
en
Compression-Ignition,
dlesel-fueled
reciprocating Internal
combustion engine
Large-bore, 6-cyllnder
opposed piston, 261-kW
(350 BhpJ/cyl, 900-rpm,
Model 38TD08-1/8
Baseline (pre-NSPS)
Fuel injection retard
aimed at meeting pro-
posed NSPS of 600 ppm
corrected to 15 per-
cent 0? and standard
atmospheric conditions
Engine exhaust:
~ SASS
Method 8
Method 5
~ Gas sample (Cj-Ce HO
Continuous NO. NOX, CO,
C02. 02, CH4. TUHC
Fuel
Lube oil
Fairbanks Morse
Division of Colt
Industries
,,Low-NOx residential
condensing heating
;system furnished by
Karlsons Blueburner
Systems Ltd. of Canada
Residential hot water
heater equipped with
M.A.N. low-NOx burner,
0.55 ml/s (O.I gal/hr)
firing capacity, con-
densing flue gas
Low-N0x burner design
by M.A.N.
Furnace exhaust:
-- SASS
~ Method 8
-- Method 5
Gas sample
Continuous , X
C02. 02. CH4, TUHC
Fuel
Waste water
New test
g HO
-- Continuous NO, NOX, CO,
'Rocketdyne/EPA
'low-NOx residential
I forced warm air furnace
Residential warm air
furnace with modified
high pressure burner and
firebox, 0.83 rol/s
(0.75 gal/hr) firing
capacl ty
Low-N0x burner design
and integrated furnace
system
Furnace exhaust:
SASS
~ Method 8
~ Controlled condensation
~ Method 5
Gas sample (Cj-Cg HO
~ Continuous NO, NOX, CO,
New test
Fuel
L.UII 11 iiuuua wu> nux »
C02, 02, CH4. TUHC
(continued)
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TABLE 1-1. (continued)
Source
Description
Test points
unit operation
Sampling protocol
Test collaborator
'Pulverized coal-fired
utility boiler,
Cpnesvllle station
400-MW tangentially
fired; new HSPS
design aimed at
meeting 301 ng/J
NO* limit
ESP Inlet and outlet.
one test
ESP Inlet and outlet:
SASS
-- Method 5
Controlled condensation
Gas sample (CpC* HC)
~ Continuous NO, NO., CO,
C02. 02
Coal
Bottom ash
ESP ash
Exxon Research and
Engineering (ER«E)
conducting cor-
rosion tests
Nova Scotia Technical
College Industrial
boiler
i
Ol
1,14 kg/s steam
(9,000 Ib/hr) firetube
fired with a mixture
of coal-oil-water (COM)
~ Baseline (COW)
Controlled SO?
emissions with .
limestone Injection
Boiler outlet:
~ SASS
Method 5
-- Method B
Controlled condensation
~ Gas sample (Cj-Cg H
Continuous 02, C0g,
HC)
Fuel
CO, NOX
Envlrocon per-
formed partlculate
and sulfur
emission tests
Adelphl University
Industrial boiler
1.89 kg/s steam
(15,000 Ib/hr)
hot water
firetube fired with a
mixture of coal-o11-
water (COM)
Baseline (COM)
Controlled SO?
emissions with
Na2C03 Injection
Boiler outlet:
~ SASS
~ Method 5
Method 8
-- Controlled condensation
~ Gas Sample (CrC6 HC)
Continuous 02, C02, NOX,
CO
Fuel
Adelphl University
Pittsburgh Energy
Technology Center (PETC)
Industrial boiler
3.03 kg/s steam
(24,000 Ib/hr) watertube
fired with a mixture of
coal-oil (COM)
Baseline test only
with COM
Boiler outlet:
~ SASS
~ Method 5
Controlled condensation
PETC and General
Electric (GE)
Continuous Oo, CO?, NO
Fuel
TUHC, CO
grab sample
-,
(continued)
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TABLE 1-1. (continued)
Source
Description
Test points
unit operation
Sampling protocol
Test collaborator
TOSCO Refinery vertical
crude oil heater
2.54 Ml/day
(16.000 bbl/day) natural
draft process heater
burning oil/refinery gas
Baseline
Staged combustion
using air Injection
lances
Heater outlet:
SASS
~ Method 5
~ Controlled condensation
-- Gas sample (CrC6 HC)
Continuous 02. NO.. CO.
CO,. HC
" NoO, grab sample
Fuel o?l
Refinery gas
KVB coordinated
the staged com-
bustion operation
and continuous
emission
monitoring
Mohawk-Getty Oil
Industrial boiler
8.21 kg/s steam
(65,000 Ib/hr)
-watertube burning
mixture of refinery gas
and residual oil
Baseline
Ammonia Injection
using the noncatalytlc
thermal deNOx
process
Economizer outlet:
~ SASS
Method 5, 17
Controlled condensation
Gas Sample (C|-Cs HC)
Ammonia emissions
NgO grab sample
Continuous Oy, NOX,
CO. C02
Fuels (refinery gas and
residual oil)
Mohawk-Getty Oil
Industrial boiler
2.52 kg/s steam
(20.000 Ib/hr) watertube
burning woodwaste
Baseline (dry wood)
Green wood
Boiler outlet:
SASS
~ Method 5
Controlled condensation
Gas sample (C^-Cc HC)
Continuous Oo, NOX, CO
Fuel
Flyash
North Carolina
Department of
Natural Resources,
EPA IERL-RTP
Industrial boiler
3.16 kg/s steam
(29.000 Ib/hr)
fire tube with refractory
firebox burning woodwaste
Baseline (dry wood)
Outlet of cyclone particulate
collector:
~ SASS
Method 5
Controlled condensation
Gas sample (Cj-Cg HC)
Continuous 02, NOX, CO
Fuel
Bottom ash
North Carolina
Department of
Natural Resources.
EPA IERL-RTP
(continued)
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TABLE 1-1. (continued)
Source
Description
Test points
unit operation
Sampling protocol
Test collaborator
Enhanced oil recovery
steam generator
15-MM (50 million Btu/hr)
steam generator burning
crude oil equipped with
MHI low-NOx burner
Performance mapping
-- Low KOX operation
Steamer outlet
SASS
Method 5
-- Method 8
Getty Oil Company,
CE-Natco
Gas sample (Cj-Cg HC)
Continuous 02, NOX. CO.
Fuel
CO?
N2& grab sample
Pittsburgh Energy
Technology Center
(PETC) industrial
boiler
3.03 kg/s steam
(24,000 Ib/hr) water tube
fired with a mixture of
coal-water slurry (CMS)
Baseline test only
with CMS
Boiler outlet
SASS
Method 5
Method 8
-- Gas sample (C}-Cg HC)
Continuous 02, NOX. CO,
COo, TUHC
MoO grab sample
Fuel
Bottom ash
Collector hopper ash
PETC
Spark-Ignited, natural-
gas-fueled reciprocating
Internal combustion
engine nonselective
NOX reduction catalyst
610-kW (818-hp) Haukesha
rich-burn engine
equipped with DuPont
NSCR system
Low-N0x (with catalyst) Catalyst inlet and outlet
15-day emissions
monitoring
~ SASS
~ NH3
HCN
N20 grab sample
-- Continuous 0?. CO?, NO*
TUHC
Lube oil
Southern California
Gas Company
Industrial boiler
180 kg/hr steam
(400 Ib/hr) stoker fired
with a mixture of coal
and plastic waste
Baseline (coal)
Coal and plastic
waste
Boiler outlet
~ SASS
~ VOST
Method 5
~ Method 8
~ HC1
-- Continuous 02, NOX,
CO*, TUHC
-- N2& grab sample
Fuel
Bottom ash
Cyclone ash
Vermont Agency of
Environmental
Conservation
CO,
(continued)
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TABLE 1-1. (concluded)
Source
Description
Test points
unit operation
Sampling protocol
Test collaborator
Industrial boiler
7.6 kg/s steam
(60,000 Ib/hr watertube
retrofit for coal water
slurry firing
Baseline test
with CHS
30-day emissions
monitoring
Boiler outlet
~ SASS
~ VOST
Method 5
~ Method 8
~ Grab sample (Cj-Ce HC)
N20 grab sample
Continuous NOX, CO, C02,
02, TUHC. SO?
Fuel
EPRI, DuPont
I i
10
Enhanced oil recovery
steam generator
15-MW (50 million Btu/hr)
steam generator burning
crude oil, equipped with
the EPA/EER low-NOx
burner
Low-N0x burner
30-day emissions
monitoring
Steamer outlet
SASS
~ VOST
~ Method 5
~ Method 8
Chevron U.S.A.,
EERC
Fuel
Controller condensation
Andersen Impactors
Grab sample (Cj-Cs HC)
N20 grab sample
Continuous NOX, CO, C02,
02, S02
Spark-Ignited,
natural-gas-fueled
reciprocating
Internal combustion
engine -- selective
NOX reduction catalyst
1.500-kW (2,000-hp)
Ingersoll-Rand engine
equipped with Engelhard
SCR system
Low NOX with catalyst
15-day emissions
monitoring
Catalyst Inlet and outlet
SASS
" NH3
~ HCR
~ N20 grab sample
-- Continuous 0?, CO?, NOX,
TUHC
Lube oil
Southern California
Gas Company
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REFERENCES FOR SECTION 1
1-1. Larkin, R. and E. B. Higginbotham, "Combustion Modification Controls
for Stationary Gas Turbines: Volume II. Utility Unit Field Test,"
EPA-600/7-81-122b, NTIS PB82-226473, July 1981.
1-2. Higginbotham, E. B., "Combustion Modification Controls for Residential
and Commercial Heating Systems: Volume II. Oil-fired Residential
Furnace Field Test," EPA-600/7-81-123b, NTIS PB82-231176, July 1981.
1-3. Higginbotham, E. B. and P. M. Goldberg, "Combustion Modification NOX
Controls for Utility Boilers: Volume I. Tangential Coal-fired Unit
Field Test," EPA-600/7-81-124a, NTIS PB82-227265, July 1981.
1-4. Sawyer, J. W. and E. B. Higginbotham, "Combustion Modification NOX
Controls for Utility Boilers: Volume II. Pulverized-coal Wall-fired
Unit Field Test," EPA-600/7-81-124b, NTIS PB82-227273, July 1981.
1-5. Sawyer, J. W. and E. B. Higginbotham, "Combustion Modification NOX
Controls for Utility Boilers: Volume III. Residual-oil Wall-fired
Unit Field Test," EPA-600/7-81-124c, NTIS PB82-227281, July 1981.
1-6. Goldberg, P. M. and E. B. Higginbotham, "Industrial Boiler Combustion
Modification NOX Controls: Volume II. Stoker Coal-fired Boiler Field
Test Site A/ EPA-600/7-81-126b, NTIS PB82-231085, July 1981.
1-7. Lips, H. I. and E. B. Higginbotham, "Industrial Boiler Combustion
Modification NOX Controls: Volume III. Stoker Coal-fired Boiler
Field Test Site B," EPA-600/7-81/126C, NTIS PB82-231093,
July 1981.
1-8. Waterland, L. R., et al., "Environmental Assessment of Stationary
Source NOX Control Technologies Final Report," EPA-600/7-82-034,
NTIS PB82-249350, May 1982.
1-9. Lentzen, D. E., etal., "IERL-RTP Procedures Manual: Level 1
Environmental Assessment (Second Edition)," EPA-600/7-78-201, NTIS
PB293795, October 1978.
1-10. Bartz, D., et al., "Control of Oxides of Nitrogen from Stationary
Sources in the South Coast Air Basin," KVB, Inc., Irvine, California,
September 1974.
1-11. "Draft Air Quality Management Plan," South Coast Air Quality
Management District, El Monte, California, October 1978.
1-10
-------
1-12. Harris, E. H., "Southern California Gas Company NOX Emission Control
Program 1982 Annual Report," Southern California Gas Company,
Los Angeles, California, February 1983.
1-13. Castaldini, C. and L. R. Waterland, "Environmental Assessment of a
Reciprocating Engine Retrofitted with Nonselective Catalytic
Reduction." EPA-600/7-84-073a, NTIS PB 84 - 224-351, June 1984.
1-11
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SECTION 2
SOURCE DESCRIPTION AND OPERATION
The tests were performed on a four-stroke turbocharged Ingersoll-Rand
412-KVS, 2,000-hp, gas compressor engine equipped with an Engelhard SCR
catalyst system. This engine is located at the SoCal Aliso Canyon compressor
station on the Northridge, California underground storage field. Table 2-1
summarizes the engine model specifications. The Engelhard Deoxo catalyst
r
system installed in Spring 1984, is a proprietary metal -oxide-based
formulation with operating temperature limits of 288° to 427°C (550° to
800°F). The catalyst, located downstream of the engine silencer, was
designed to reduce NOX emissions by 80 percent or greater, and thereby meet
the SCAQMD rule 1110.1. The reducing agent, anhydrous NH3 gas, is injected
into the exhaust gas to react with NOX and 02 in the presence of this metal
catalyst and reduce both NO and N0£. The SCR chemical reaction process is
typically envisioned to be as follows:
4NHa + 4NO + 02 * 4N2 +
i
4NH3 + 2N02 + 02 * 3N2 + 6H20
The SCR process requires fuel -lean engine operation and the addition of the
reducing agent NH3 in the flue gas upstream of the catalyst. An additional
requirement is the NHs control system whose function is to maintain the
appropriate NHa/NO molar ratio (generally set for 1.0 for _>90 percent NOX
2-1
-------
TABLE 2-1. ENGINE/COMPRESSOR SPECIFICATION
Engine:
Manufacturer
Model
Cycle
Air charging
Number of cylinders
Bore
Stroke
Displacement/cylinder
Compression ratio
BMEP
Bhp/cyl at rpm
Compressor:
Manufacturer
Bore (first stage)
Stroke (first stage)
Bore (second stage)
Stroke (second stage)
Ingersoll-Rand
412DT-KVS
4-strokes
Turbocharged (dual)
V-12
0.387m (15.25 in.)
0.487m (18.0 in.)
44.8 1 (2,735 in.3)
6.5:1
1.00 MPa (146 psi)
125 kW (167 Bhp) at 330 rpm
Ingersoll-Rand
0.235m (9.25 in.)
0.381m (15.2 in.)
0.159m (6.25 in.)
0.381m (15.2 in.)
2-2
-------
reduction) with varying NOX concentrations in the exhaust gas and varying
engine load. For the Aliso Canyon site, Engelhard installed an ammonia
control system which includes a chemiluminescent NOX analyzer to determine
the concentrations upstream and downstream of the catalyst and a
microprocessor to compare the values and control the ammonia flowrate.
Parametric testing of this catalyst conducted in 1982 on slip stream exhaust
indicated 90 percent NOX reduction capability with 100 ppm NH3 carryover for
NH3/NO of about 1.0 and a gas temperature in the range of about 400° to 4508C
(750° to 850°F) (Reference 2-1).
During the CMEA tests, exhaust emissions (NOX, 0£, CO, COg), and total
unburned hydrocarbon (TUHC) were measured on a continuous basis for a period
of 15 days during normal engine operation. In addition, a comprehensive
emission test program was performed over a 1-day period during which engine
load and NH3 flowrate were controlled for catalyst NOX reduction of about
80 percent. Table 2-2 summarizes the engine operation and ambient
atmospheric conditions during this 1-day comprehensive testing period.
As noted, engine load was maintained relatively constant throughout the
comprehensive test period. Engine power output of 1,270 kWt (1.700 Bhp) was
calculated using compressor performance curves available from the
manufacturer. Heat rate based on fuel lower heating value was measured to be
about 9,400 kJ/kWh (6,600 Btu/Bhp-hr). Measured turbocharger turbine gas
outlet temperature varied from 370° to 390°C (700° to 740°F). These
measurements are considered in error (low) though, as suggested by the
catalyst inlet temperature measurement which was between 390° to 400°C (740°
to 750°F).
2-3
-------
TABLE 2-2. ENGINE OPERATION
Parameter Range Average
Ambient
Dry bulb temperature, *C CF) 22 to 33 (72 to 92) 29 (84)
Wet bulb temperature, *C CF) 19 to 21 (67 to 70) 20 (68)
Relative humidity, percent 45 to 55 50
Barometric pressure. kPa (In. Hg) 96.2 (28.5)
Engine Operation
Engine load, kHt (Bhp)a 1,270 (1,700
Fuel flow, scm/fir (scfh) ~ 327 (11,550)
Heat input, MM (million Btu/hr)° 3.29 (11.2)
Specific fuel consumption, kJ/kHh 9,390 (6,610)
(Btu/Bhp-hr)°
Air manifold pressure. kPa (psig) 25 to 28 (3.6 to 4.0) 26.5 (3.85)
Air manifold temperature 'C CF) 68 to 70 (154 to 158) 69 (156)
Speed, rpm 320 to 333 325
Exhaust manifold temperatures, *C CF) 380 to 382 (716 to 720) 380 (718)
No. 1 cylinder 292 to 360 (560 to 680) 332 (630)
No. 2 cylinder 440 to 455 (820 to 850) 449 (840)
No. 3 cylinder 430 to 440 (800 to 820) 430 (810)
No. 4 cylinder 380 to 390 (720 to 730) 385 (725)
No. 5 cylinder 404 to 415 (760 to 780) 410 (775)
No. 6 cylinder 290 to 350 (550 to 660) 320 (610)
No. 7 cylinder 380 to 390 (710 to 730) 380 (720)
No. 8 cylinder 360 to 370 (680 to 700) 363 (685)
No. 9 cylinder 380 to 390 (700 to 740) 390 (730)
No. 10 cylinder 370 to 393 (700 to 730) 380 (715)
No. 11 cylinder 365 to 370 (690 to 700) 370 (722)
No. 12 cylinder 396 to 404 (745 to 760) 404 (760)
Turbine outlet temperature, *C CF)
L 380 to 390 (720 to 740) 390 (730)
R 370 to 380 (700 to 740) 380 (720)
Catalyst Inlet temperature. *C CF) 390 to 400 (740 to 750) 396 (745)
Catalyst outlet temperature, *C CF) 344 to 382 (652 to 720) 362 (683)
Gas Compressor
Suction pressure, MPa (psig) 4.02 (583)
Interstage pressure, MPa (psig) 7.86 (1,140)
Discharge pressure, MPa (psig) 19.97 (2,898)
Suction temperature. *C CF) 26 to 35 (78 to 95) 29 (85)
Interstage temperature. *C CF) 88 to 93 (190 to 200) 91 (195)
Discharge temperature. "C CF) 107 to 118 (225 to 245) 113 (235)
NH? System
NH3 flowate. standard T/s (scfh) 4.44 to 4.88 (565 to 620) 4.64 (590)
^Engine load obtained from engine performance curves.
DHeat Input based on low heating value (LHV) of natural gas from Table 2-3.
Specific fuel consumption based on LHV of fuel.
2-4
-------
Ammonia injection rate varied from 4.44 to 4.88 standard 1/s (565 to
620 scfh), corresponding to a NHs/NO molar ratio of about 1.04 to 1.10.
Average NH3 injection rate was about 464 standard 1/s (590 scfh)
corresponding to a NHa/NO ratio of 1.07.
Table 2-3 summarizes the typical analysis of the natural gas fuel.
This analysis, provided by SoCal, corresponds to a sample obtained prior to
the comprehensive test program.
It should be noted that prior to the test period, problems were
experienced with the 1% control system, specifically the NOX analyses and
also the NH3 control valve.
i
TABLE 2-3. NATURAL GAS FUEL ANALYSIS**
Component
CH4
^2^6
C3H8
C^HIQ
C5H12
CfiH14
C02
N2
Percent by volume
89.7
5.75
1.50
0.40
0.128
0.147
0.947
1.30
High heating valueb MJ/m3 (Btu/ft3)
39.8 (1,070)
i
Low heating valueb 36.2 (973)
Specific gravity 0.622
aTypical fuel analysis
Calculated heating value
2-5
-------
REFERENCE FOR SECTION 2
2-1. Harris, E. H., "Southern California Gas Company NOX Emission Control
Program 1982 Annual Report," Southern California Gas Company,
Los Angeles, California, February 1983.
2-6
-------
SECTION 3
EMISSION RESULTS
The objectives of this test program were: (1) to measure engine exhaust
emissions during a 15-day test period to evaluate the continuous performance
of the catalyst, utilizing continuous NOX and other gas emission analyzers,
and (2) to perform comprehensive tests over a 1-day period to measure the
effect of the catalyst on organic emissions as well as on NH3 breakthrough
and possible formation of HCN. Emission measurements were performed in
cooperation with SoCal, owner and operator of the test site, whose field
crew and equipment included an emission monitoring laboratory with operating
staff.
3.1 SAMPLING PROTOCOL
Figure 3-1 illustrates a schematic of the test site highlighting the
sampling locations, sampling and analytical test matrix, and the test team
performing the sampling and evaluation. As indicated, continuous monitoring
of flue gas was performed alternatively upstream and downstream of the
catalytic reactor utilizing heated; sample lines. The catalyst inlet sampling
A
location for the continuous monitors was upstream of the NHa injection
location to avoid any effect of added NH3 on the engine exhaust NOX
measurements. The sampling and gas conditioning system for this test program
included continuous monitors for 0£, COg, CO, NO, NOX, and TUHC. The
continuous monitors were operated throughout a 15-day test period while
3-1
-------
Stack
gas
I >
i
Muffler
1
NSCR
catalyst
T t
NH3 injection
Sample Location
A Natural
gas to
engine
B,D Catalyst
Inlet,
outlet
C,0 Catalyst
inlet,
outlet
Type of Sample
Grab sample Fuel
Extractive Sample
Continuous Monitors
Volatile organic
sampling train (VOST)
Sampling train
SASS
Analyses^
Sampling train
Modified Method 6
Sampling train
Modified Method 6
Grab sample Gas
bomb
Grab sample --
Method 7 flasks
Gas chromatography for
composition; heating value,
specific gravity
02, C02, CO, TUHC, MO, NOX,
Volatile organics in
accordance with EPA Method
624 (catalyst outlet only)
Particulate by gravimetry,
total semi volatile
organics by GC/FID, total
nonvolatile organics by
gravimetry, and semi- and
nonvolatile organic
compounds in accordance
with EPA Method 625
NH3 by selective ion
electrode
HCN by wet chemistry
N20 by GC/ECD
MOX by Method 7
Test
Number
SoCal
Acurex
SoCalb
Acurex
Acurex
Acurex
Acurex
Acurex
Acurex
Measurement and analysis techniques used are discussed in detail in
Appendix A
bNOx measurements also provided by SoCal as part of the NH3 Control System
Figure 3-1. Sampling sites and analysis test matrix.
3-2
-------
engine load and NH3 injection rate varied slightly. Certification of the NOX
analyzer readings was attempted once during this 15-day test period using
standard EPA Method 7 protocol.
The source assessment sampling system (SASS), the NH3, and the HCN
sampling trains were operated during 1 day of tests at both the inlet and
outlet of the catalytic converter. Catalyst inlet location for these
sampling systems was downstream of the 1% injection location. Simultaneous
inlet and outlet samples were performed to measure any change in the
composition of the exhaust gas across the catalyst. Volatile organics were
measured at the catalyst outlet only using the volatile organic sampling
train (YOST) per EPA protocol (Reference 3-1). These measurements were
i
performed while engine load was maintained constant and NH3 injection rate
was adjusted for about 80 percent NOX reduction by the catalyst.
Figure 3-2 illustrates the actual test activity schedule. The following
sections summarize the emission results. Sections 3.2 and 3.3 present
emission results obtained during the comprehensive tests that took place on
August 3, 1984. Section 3.4 summarizes results of continuous emission
measurements performed over the 15-day test period. EPA Method 7
certification tests, performed on August 2, 1984, are discussed in Section 4.
Details of the sampling and analysis procedures used are discussed in
Appendix A.
3.2 CRITERIA POLLUTANT AND OTHER VAPOR SPECIES EMISSIONS
Table 3-1 summarizes gaseous and particulate emissions measured during
the 1-day comprehensive tests performed at about the half-way point of the
15-day continuous monitoring period. Exhaust Q% was about 11.2 percent at
3-3
-------
Test activity
Continuous monitors /
(inlet/outlet)
Comprehensive tests
(inlet/outlet)
VOST (outlet only)
~ SASS
~ NH3
-- HCN
N20
Method 7 certification
July August
26 27 28 29 30 31 1 2 3 4 5 6 7 8 9
* A <
A
A
A
A
A
A
Figure 3-2. Test activity schedule.
3-4
-------
TABLE 3-1. CRITERIA AND OTHER GAS PHASE SPECIES
EMISSIONS: COMPREHENSIVE TESTS
Pollutant*
Catalyst inlet
Catalyst outlet
As measured by continuous
gas analyzers, range (average):
Og, percent dry
C02, percent dry
CO, ppm dry
NOX, ppm dry
TUHC, ppm dry of CH4f
11.1 to 11.3 (11.2)
5.0 to 5.9 (5.5)
180 to 310 (245)
2,200 to 2.600 (2,400)
NA
10.9 to 11.2 (11.1)
5.1 to 6.0 (5.6)
170 to 280 (225)
330 to 560 (445)
NA
Corrected average gaseous
emissions:
CO
N0xe
TUHCf
NH39
Total cyanide*1
Solid participate:
SASS solids
ppmb
150
1,470
1,084
0.004
ng/Jc
171
2,760
NA
752
0.004
g/Bhp-hrd
1.19
19.2
5.23
3 x 10-5
Negligible
ppmb ng/Jc
138 158
273 513
NA
56 39
1.3 1.4
g/Bhp-hrd
1.10
3.57
0.27
0.010
Negligible
aAppendix A discusses continuous monitor analyses used, sample gas conditioning system,
particulate sampling equipment, and other sampling trains and procedures
Corrected to 15 percent 02, dry
On heat input basis using fuel's lower heating value
"Shaft output basis
-------
both the inlet and outTet location. This indicates an air-fuel ratio of
about 35 on a weight basis.
NOX emissions at the engine outlet varied from 2,200 to 2,600 ppm as
measured, with an average of 2,400 ppm, corresponding to about 2.76 mg/J heat
input basis (19.2 g/Bhp-hr shaft output). NOX reduction efficiency by the
catalyst ranged between 78 to 85 percent with an average for the day of
81 percent. CO emissions were approximately 10 percent lower at the catalyst
outlet compared to the emissions measured in the untreated engine exhaust.
Unburned hydrocarbon data were not available for the comprehensive test
period due to instrument malfunction. However, test data obtained prior to
and following these tests showed TUHC concentration in the range of about
1,500 to 1,800 ppm as measured at both inlet and outlet locations.
NH3 emissions were measured using a wet impinger method and a continuous
method using a NOX analyzer. Sampling of NH3 using the impinger train took
place at the inlet to the catalyst, downstream of the NH3 injection location.
Therefore, the measured concentration of NH3 at this location is the direct
result of the NH3 injected in the engine exhaust for the catalytic reduction
of NOX. NH3 concentrations at this location ranged from 1,450 to 2,090 ppm
obtained with two separate gas samples. The NH3 injection rate during this
test period was recorded in the range of 4.44 to 4.88 1/s (565 to 620 scfh)
which would result in a concentration of 2,422 to 2,700 ppm in the engine
exhaust. Therefore, the amount of NH3 measured at the catalyst inlet by wet
chemical analysis accounts for about 60 to 77 percent of the measured NH3
injection rate.
Table 3-2 summarizes the NH3 gas concentrations recorded using
continuous gas monitors. Using two NOX analyzers, the NH3 was measured by
3-6
-------
TABLE 3-2. AMMONIA MEASUREMENTS, PPM DRY AS MEASURED
Percent
Emission9 Catalyst inletb Catalyst outlet change
1. NO 2,000 to 2,400 (2,200) 300 to 590 (445) -80
2. NO + N02 2,000 to 2,600 (2,400) 330 to 560 (445) -81
3. NO + N02 + NH3 2,200 to 2,600 (2,400) 390 to 622 (505) -79
4. NH3 0 20 to 140 (80)
(by difference 3-2)
5. NH3 by wet method0 NA 65 to 118 (92)
aYalues for emissions (1 through 4) were recorded using continuous analyzers
^Measurements upstream of NH3 injection location
CNH3 measurements by wet method were made downstream of NH3 injection
location, therefore a wet method measurement at the catalyst inlet is not
available
3-7
-------
the difference in readouts between NO + N0£ and NO + N02 + NH3. Appendix A
describes in detail the technique used. Upstream of the NH3 injection
location, the two analyzers showed no difference, indicating no MH3 present,
as expected. At the catalyst outlet location, the two analyzers indicated
NH3 concentration in the range of 20 to 140 ppm as measured. Using two
separate wet chemical analysis measurements, NH3 at this location was
recorded at 65 and 118 ppm, respectively. Average values were 80 ppm using
continuous monitors and about 90 ppm using wet chemical analysis.
Additional sampling was performed to quantitate cyanide and particulate
levels in the exhaust across the catalyst. Total cyanides, as HCN, increased
by three orders of magnitude from an average of about 4 pg/J (30 yg/Bhp-hr) to
1.4 ng/J (10 mg/Bhp-hr). Particulate emission levels were negligible at both
sample locations (actual particulate matter collected on the filter showed a
decrease after corrections for filter tare and blank).
NgO emissions were measured by gas chromatography with electron capture
detection of exhaust gas grab samples taken at the inlet and outlet of the
catalyst. Table 3-3 summarizes results of the N20 emissions sampled on
August 8. Corresponding exhaust NOX levels are also shown in the table. As
indicated, at the time the N20 samples were taken the SCR system was effecting
about 80 percent NOX reduction. Interestingly, N20 levels were reduced about
60 percent by the catalyst. The ^0 level was about 4 percent of NOX level in
the exhaust at the catalyst inlet and about 9 percent at the catalyst outlet.
These are significantly lower than the fractions measured in tests of external
combustion sources, which fall in the 15 to 25 percent range (Reference 3-2).
However, the ^0 fractions measured in tests of a rich-running engine were
also low (2 to 3 percent of NOX emission levels) (Reference 3-3).
3-8
-------
TABLE 3-3. N20 EMISSIONS: 1C ENGINE/SCR TESTS3
NOX,
N20,
Compound
ppm measured
ppm at 15% 02
ppm measured
ppm at 15% 02
Catalyst
inlet
2,600
1,640
98
62
Catalyst
outlet
490
300
43
26
Percent
reduction
82
57
aTests performed on August 8
3.3 ORGANIC SPECIES EMISSIONS
Organic analyses were performed on the exhaust gas samples collected at
the catalyst inlet and outlet locations. SASS samples were analyzed for
total semivolatile and nonvolatile organics according to the EPA Level 1
protocol (Reference 3-4) as outlined in Appendix A. Semivolatile organic
compounds with boiling points in the nominal Cj to CIQ range of 100° to 300°C
(210° to 570°F) were determined in the laboratory by total chromatographable
organic (TCO) analysis of the combined organic module sorbent (XAD-2) and
condensate extracts. Nonvolatile organic species having boiling points in
the nominal CIQ+ range of >300°C (570°F) were measured by gravimetric (GRAY)
analysis of SASS sample extracts.
Infrared speetrometry (IR) was performed on the GRAV residue of SASS
train extracts to identify organic functional groups possibly present. Gas
chromatography/mass speetrometry (GC/MS) analyses of the XAD-2 extracts were
also performed to identify specific polynuclear aromatic hydrocarbons (PAH).
and other organic components (the semivolatile organic priority pollutants).
3-9
-------
The components sought in the GC/MS analysis and their respective detection
limits are listed in Table 3-4.
In addition, emissions of volatile organics were measured at the
catalyst outlet using the volatile organic sampling train (YOST) protocol per
EPA procedures (Reference 3-1). Analysis of VOST samples was performed also
by GC/MS. Volatile organic compounds sought in this analysis are listed in
Table 3-5.
3.3.1 TCP. GRAV. GC/MS, and IR Analyses of SASS Sample Extracts
Table 3-6 summarizes the results of the organic analyses of the SASS
train XAO-2 sorbent module extract for the catalyst inlet and outlet tests.
As noted, total organic emissions decreased about 70 percent across the
catalyst from 4.9 to 1.5 mg/dscm. The greatest reduction apparently occurred
in the nonvolatile fraction. This fraction accounted for 65 percent of the
total organic at the catalyst inlet, but only 40 percent at the catalyst
outlet.
Two polynuclear aromatic hydrocarbon (PAH) compounds (naphthalene and
phenanthrene) and a nitrophenol were measured in the exhaust at the catalyst
inlet. Levels of these were significantly reduced at the catalyst outlet.
Concentrations were below 10 yg/dscm (about 40 ug/Bhp-hr) for both test
locations.
Table 3-7 summarizes the results of the IR analysis of organic module
extracts. The data suggest the presence of aliphatic hydrocarbons and
possibly some oxygenated hydrocarbons at both the inlet and outlet locations.
3-10
-------
TABLE 3-4. COMPOUNDS SOUGHT IN THE GC/MS AND THEIR DETECTION LIMITS
INJECTED)
Aci d Compounds
2,4,6-trichlorophenol
p-chloro-m-cresol
2-chlorophenol
2,4-dichlorophenol
2,4-dimethylphenol
5 2-m'trophenol
5 4-nitrophenol
5 2,4-dinitrophenol
5 4,6-dinitro-o-cresol
5 pentachlorophenol
phenol
Base Neutral Compounds
1,2,4-trichlorobenzene 1
1,2-dichlorobenzene 1
1,2-diphenylhydrazine . 1
(as azobenzene)
1,3-dichlorobenzene 1
1,4-dichlorobenzene ' 1
2,4-dinitrotoluene 1
2,6-dinitrotoluene 1
2-chloronaphthalene 1
3,3'-dichlorobenzid1ne 5
3-methyl cholanthrene 40
4-bromopheny! phenyl ether 1
4-chlorophenyl phenyl ether 1
7,12-dimethyl benz(a)anthracene 40
N-nitrosodi-n-propylamine 5
N-nitrosodimethylamine NA
N-nitrosodiphenylamine 1
acenaphthene 1
acenaththylene 1
anthracene 1
benzo(ghi)perylene 5
benzidine 20
benzo(b)fluoranthene 1
benzo(k)fluoranthene 1
benzo(a)anthracene 1
benzo(a)pyrene l 1
benzo(c)phenanthrene
bis(2-chloroethoxy)methane
bis(2-chloroethyl)ether
bis(2-chloroisopropylJether
bis(2-ethylhexylJphthalate
butyl benzyl phthalate
chrysene
di-n-butyl phthalate
di-n-octyl phthalate
dibenzo(a,h)anthracene
dibenzo(c,g)carbazole
diethyl phthalate
dimethyl phthalate
fluoranthene
fluorene
hexachlorobenzene
hexachlorobutadiene
hexachlorocyclopentadiene
hexachloroethane
indeno(l,2,3-cd)pyrene
isophorone
naphthalene
nitrobenzene
perylene
phenanthrene
pyrene
5
20
20
20
5
1
40
1
1
1
1
1
1
1
1
5
40
1
1
1
1
1
1
1
1
5
1
1
1
40
1
1
3-11
-------
TABLE 3-5. VOLATILE ORGANICS SOUGHT IN GC/MS ANALYSIS
Chlorinated All p ha tics
Chioromethane
Dichlorome thane
Chloroform
Tetrachlorome thane
Chloroethane
1,.
1,
,1-dichloroethane
,2-di chloroe thane
1,1,1-trichloroethane
1,1,2-trichloroethane
1,1,2,2-tetrachloroethane
1,2-dichloropropane
Hexachlorocyclohexane
Vinyl chloride
1,1-dichloroethylene
1,2-dichloroethylene
Tri chloroe thy1ene
Tetrachloroethylene
Alky! chloride
1,3-dichloropropene
Chloroprene
Ethers
Ethylene oxide
Propylene oxide
Chlorinated Ethers
Epichlorohydrin
2-chloroethyl vinyl ether
Aldehydes
Acetaldehyde
Acrolein
Amines and Nitriles
Aerylorn* trile
Aromatic Hydrocarbons
Benzene
To!uene
Ethyl benzene
o-xylene
m-xylene
p-xylene
Chlorinated Aromatics
Chlorobenzene
3-12
-------
TABLE 3-6. TOTAL ORGANIC AND SEMIVOLATILE ORGANIC PRIORITY POLLUTANT
EMISSIONS: 1C ENGINE/SCR SYSTEM TESTS, XAD-2 PLUS OMC EXTRACT
Component
Total semi volatile organics
(C, to C16 by TCO)
Total nonvolatile organics
(Ci5+ by gravimetry)
Total semi- and nonvolatile
orgam cs
Semi volatile organic
priority pollutants
Naphthalene
Phenanthrene
2-Nitrophenol
Oi-n-butyl phthalateb
Bis (2-ethylhexyl) phthalateb
Other semi volatile
organic priority pollutants
Catalyst
(mg/ train)
44
83
127
(vg/ train)
220
10
140
80
50
<10
inlet
(mg/dscm)
1.7
3.2
4.9
(yg/dscm)
8.4
0.4
5.3
3.1
1.9
<0.4
Catalyst
(mg/ train)
22*
16
38
(yg/train)a
10
<10
<10
140
25
<10
outlet
(mg/dscm)
0.9
0.6
1.5
(yg/dscm)
0.4
<0.4
<0.4
5.5
1.0
<0.4
aAverage of duplicate injections
^Suspected contaminants, commonly found in laboratory blanks
3-13
-------
TABLE 3-7. IR SPECTRA SUMMARY
Sample
XAD-2 + OMC extract,
catalyst inlet
XAD-2 + OMC extract,
catalyst outlet
Wave
number
(cm"1) Intensity3 Assignment
3350
2955
2920
2850
1570
1460
1340
1260
1055
950
880
770
700
635
2955
2920
2850
1710
1450
1410
1255
800
W
S
S
S
S
S
W
M
M
W
M
W
W
W
S
S
S
S
M
W
S
M
OH stretch
CH alky!
CH alkyl
CH alkyl
Not assigned
CH bendb
CH bendb
C-0 stretchb
C-0 stretchb
C-C stretch
CH rock
CH rock
CH rock
CH rock
CH alkyl
CH alkyl
CH alkyl
C=0 stretch
CH bendb
CH bendb
C-0 stretch
CH rock
Possible compound
categories present
Aliphatic hydro-
carbons possibly
with some
oxygenates
such as aldehydes
and alcohols
Aliphatic hydro-
carbons possibly
with some oxy-
genates such as
carboxylic acids
and ketones
*S = strong, M = moderate, W = weak
tentative assignment
3-14
-------
3.3.2 Volatile Organic Emissions
Table 3-8 summarizes results of the volatile organic sampling train
(VOST) testing of the engine. Only one abbreviated set (two runs) of VOST
tests was performed; sampling was at the catalyst outlet. As shown, benzene
and several substituted benzenes were emitted at highest concentrations:
benzene at 915 ug/dscm, toluene at 247 ug/dscm, xylenes at 85 ug/dscm,
chlorobenzene at 61 ug/dscm, and ethylbenzene at 20 yg/dscm. Small amounts
of chlorinated ethylenes and ethanes were also detected, although these
compounds are often Tenax contaminants. The protocol is described in
Appendix A.
3.4 EXTENDED CONTINUOUS EMISSION MONITORING
Continuous monitoring for exhaust gas 02, C02, CO, NOX, and TUHC was
performed over a 15-day period from July 26 to August 9, 1984. Actual
emission measurements for SCR performance did not begin until July 27 due
to NH3 feed problems and control. The engine was operated under normal
conditions with no restrictions on load during this period. NHs injection
rate was controlled by the automatic NOX feedback system installed on this
unit as part of the SCR control package. NH3 feedrate was set to provide
80 percent reduction in NOX. Figures 3-3 through 3-8 illustrate emission
data obtained over this test period. 'The emission data represent hourly
averages of the data taken on 5- to 15-min intervals.
Exhaust Q£ and C02, illustrated in Figure 3-3, show that engine
operation was fairly steady throughout the 14 days of actual emissions
testing. Gaps on the test data indicate engine shutdowns generally due to
lubrication system malfunction. This is most evident during the period
3-15
-------
TABLE 3-8. VOLATILE ORGANIC SAMPLING TRAIN RESULTS: CATALYST OUTLETS
Compound
Benzene
Chlorobenzene
1,2-dlchloroe thane
1,1,1-trlchloroe thane
1,1,2,2-tetrachloroethane
Chi oroe thane
Chloroform
1,1-dlchloroethene
t-l,2-d1chloroethene
Ethylbenzene
Methylene chloride
Chlorome thane
Bromome thane
Tetrachloroethene
Toluene
Trichloroethene
Vinyl chloride
Acetone
Total xylenes
Field
blank
(ug/trap
pair)
NDC
NO
ND
45
ND
ND
ND
ND
ND
ND
1.205
111
5
ND
ND
ND
ND
5
ND
Method
blank
(ug/trap
pair)
13
5
ND
ND
9
ND
ND
ND
ND
5
38
58
2
ND
31
ND
ND
ND
10
Run 1
dig/trap pair)
Measured
ND
1.700
ND
ND
60
56
11
31
7
700
1.200
155
6
ND
6,000
ND
11
720
ND
Corrected0
__
1.700
56
31
-
695
5,970
715
(ug/dscm)
corrected0
M.
81
2.7
1.5
~
33
285
34
Run 2
(pg/trap pair)
Measured
32,000
720
5
101
11
16
10
26
ND
127
1,700
130
5
85
3,700
3
5
ND
3.000
Corrected0
32,000
715
16
26
--
122
85
3,670
2.990
(ug/dscm)
corrected0
1.830
41
«
0.9
1.5
7.0
4.8
209
170
Average
(jjg/dscm)
915
61
1.8
1.5
20
~
2.4
247
17
85
aTraps desorbed and analyzed In pairs (Tenax and Tenax/charcoal)
"Corrected = measured maximum of field or method blank. If this not greater than 10 times the blank value and greater
than 10 times the method detection limit of 1 ng/trap pair, then assumed not significant, denoted by double dashes.
CND denotes less than the method detection limit of 1 ng/trap pair
-------
12-,
10-
*
^
£
CD
U
5-
OJ
CsJ
o
. 6-
CM
O
<0
-C
X
4 _
X
X
X
2 _
o
A
X
Inlet
Inlet CO,
Outlet 0,
Outlet CO.
I
6 8
Test day
I
10
\
12
14
Figure 3-3.
Exhaust 02 and C02 for the extended continuous monitoring
period.
3-17
-------
2,000-,
Inlet N0x
Outlet NO,
o
+->
1,600-
O
U)
»-«
00
&
in
I
o
z
1.200-
800-
Ul
8
400-
T~ r
6 8
Test day
10
12
Figure 3-4. Exhaust NOX levels for the extended continuous
monitoring period.
-------
lOO-i
Ol
a.
80-
o
o
u
£ 60
u
c
o
40-
20-
i
10
n
12
14
Test day
Figure 3-5.
Catalyst NOX reduction efficiency for the
extended monitoring period.
3-19
-------
00 -i
00 -
DO -
O
DO -
DO -
Test day
*e 3-6. Catalyst outlet NH3 emissions for the extended continuous
monitoring period.
3-20
-------
W
o
*->
£
4,000 -
3,000-J
|
~ 2,000 -|
8
1.000 -J
0
A
O Inlet CO
A Outlet CO
10
12
Test day
Figure 3-7. Exhaust CO levels for the extended continuous
monitoring period.
-------
3,000-,
2,500-
5 2,000-
£
E 1,500 -
a
10
£
1,000-
500 -
(D Inlet TUHC
A Outlet TUHC
6 8
Test day
o
A
10
12
14
Figure 3-8.
Exhaust hydrocarbon levels for the extended
continuous monitoring period.
3-22
-------
August 5 to 7. Comprehensive tests discussed in the previous sections were
performed on August 3.
NOX emissions are illustrated in Figure 3-4. Catalyst inlet levels
ranged from 1,200 to 1,600 ppm corrected to 15 percent 03. Catalyst outlet
levels ranged from about 100 to 400 ppm (at 15 percent 03) with most of the
measurements showing NOX of about 200 ppm. Corresponding NOX reduction
efficiencies are shown in Figure 3-5. Catalyst performance averaged about
80 percent with the exception of a brief period during August when NH3
flowrate was accidentally interrupted.
Figure 3-6 illustrates the catalyst outlet NH3 recorded using continuous
NOX analyzers as described in Appendix A. For the most part, NH3 emissions
throughout the test period were about 55 ppm at 15 percent Og (90 ppm as
measured). Figures 3-7 and 3-8 illustrate trends in both CO and TUHC
emissions. CO emissions showed a large variation from about 60 to 300 ppm
(also corrected to 15 percent 02). Changes in CO from average values of
about 140 to 150 ppm recorded during the comprehensive tests may be
attributed to surges in engine load recorded during some portion of the test
period and small variations in air/fuel ratios and ambient temperatures.
TUHC data were not obtained for much of the test period due to instrument
malfunction. Available data indicate TUHC levels in the range of about 750
to 1,250 ppm (at 15 percent 03) with no significant difference between the
catalyst inlet and outlet locations.
3-23
-------
REFERENCES FOR SECTION 3
3-1. "Protocol for the Collection and Analysis of Volatile POHC's Using
VOST," EPA-600/8-84-007, NTIS PB84-170042, March 1984.
3-2. Waterland, L. R., etal., "Environmental Assessment of Industrial
Boilers Firing Coal-Liquid Mixtures and Wood," in Proceedings of the
1982 Joint Symposium of Stationary Combustion NOX Control, Volume II.
EPA 600/9-85-022b, NTIS PB 85-235612, July 1985.
3-3. Castaldini, C. and L. R. Waterland, "Environmental Assessment of a
Reciprocating Engine Retrofitted with Nonselective Catalytic
Reduction," EPA 600/7-84-073a, NTIS PB84-224351, June 1984.
3-4. Lentzen, D. E., et al., "IERI-RTP Procedures Manual: Level 1
Environmental Assessement Second Edition," EPA-600/7-78-201,
NTIS PB 293795, Octoberl978.
3-24
-------
SECTION 4
QUALITY ASSURANCE ACTIVITIES
Specific quality assurance (QA) activities performed to determine the
accuracy and precision of the measurements made in this test program
included:
Performing EPA Method 7 certification tests to establish the
accuracy of the NOX continuous analyzers used in the tests
Spiking a sample of cleaned XAD-2 resin with TCO, GRAY, and
semivolatile priority pollutant compounds and analyzing the spiked
resin to determine the accuracy (recovery) of the resin extraction
and subsequent analyses
Analyzing a blind spike sample for ammonia to determine the accuracy
of the selective ion electrode analysis technique used
Performing duplicate TCO and GC/MS injections on the SASS train
XAD-2 extract to determine the precision of these measurements
The following paragraphs discuss results of these QA activities.
4.1 NOX CERTIFICATION RESULTS
A i
EPA Method 7 tests were performed once during the 15-day continuous
monitoring period, on August 2, 1984. The intent of the tests was to certify
the NOX analyzers by simultaneous measurement of emissions at the catalyst
outlet. NOX emissions by continuous monitors at the catalyst outlet measured
between 330 and 550 ppm, dry (445 ppm average) at stack conditions of about
4-1
-------
11 percent 03. By contrast, EPA Method 7 results obtained from 27 separate
samples Indicated NOX levels between 40 and 370 ppm with an average value of
about 132 ppm. During the same test period, visual observation of the SoCal
NOX monitoring instrumentation indicated NOX in the range of 350 to 600 at
the catalyst outlet, reflecting SCR NOX reduction performance settings of 80
percent. These SoCal NOX measurements using continuous monitors were
generally in good agreement with emissions recorded by the Acurex monitors.
Both SoCal and Acurex NOX instrumentation consisted of Thermo-Electron Model
10 AR monitors equipped with molybdenum and stainless steel converters. The
Acurex monitors (two were used as discussed in Appendix A) were calibrated at
least twice daily with high (2750 ppm), low (190 ppm), and zero (nitrogen)
certified span gases. SoCal and Acurex monitors were also found to be in
relatively good agreement for catalyst inlet NOX concentrations (less than 2
percent). In light of agreement between emissions obtained by SoCal and
Acurex using continuous monitors, the EPA Method 7 results are deemed
suspect. Therefore, results of the monitor certification tests are
considered inconclusive.
4.2 SPIKED XAD-2 RESIN ANALYSES
After extraction of the XAD-2 field blank, the same resin was spiked
with 10 mg bis(2-ethylhexyl)phthaiate, 40 mg hexadecane, and 400 yg each of
naphthalene, phenanthrene, pyrene, and dodecane. Thus, this resin contained
41 mg TCO compounds (dodecane, hexadecane, and naphthalene), 51 mg GRAY
compounds (the phthalate, phenanthrene, pyrene and hexadecane), and 400 yg
each of three polynuclear aromatics for the semivolatile organic priority
pollutant analysis (hexadecane will respond in both the TCO and GRAV
analyses).
4-2
-------
TABLE 4-1. XAD-2 RESIN SPIKE AND RECOVERY RESULTS
Measurement
Spiked Recovered
amount amount Percent Implied Accuracy
(mg) (mg) recovery accuracy objective4
Total chromatographable
organics (TCO)
Gravimetric organics
41.0
51.0
29.0
39.0
71
76
-29
-24
±50
±50
(GRAY)
Semivolatile organic
priority pollutants:
Naphthalene
Phenanthrene
Pyrene
Bis (2-ethylhexyl)
phthalate
Average
0.4
0.4
0.4
0.4
0.31
0.34
0.25
0.28
78
85
62
70
-22
-15
-38
-30
-50
+100
Reference 4-1.
4-3
-------
Results of the analyses of this spiked resin are shown in Table 4-1. As
noted, the recovery of the TCO analysis was 71 percent, the GRAY analysis
was 76 percent, and averaged 74 percent for the GC/MS analyses. If these are
interpreted to be the accuracy of these measurements, all fall within the
project accuracy objective (Reference 4-1) also noted in Table 4-1.
4.3 AMMONIA SPIKE SAMPLE ANALYSIS
An ammonia audit sample was prepared by adding a known amount of
ammonium hydroxide to a volume of 0.1N HC1 and submitted as a blind spike for
analysis. The analysis result was 0.38 mg NH3 per ml of solution, versus the
spiked amount of 0.48 mg/ml. This implies an analytical accuracy of
-21 percent.
4.4 DUPLICATE ORGANIC ANALYSES OF XAD-2 EXTRACT
The XAD-2 extract samples from the catalyst outlet SASS train for this
test were analyzed in duplicate for TCO content, and for the semivolatile
organic priority pollutants and other major peaks by GC/MS. The two TCO
measures were 21 and 24 mg/train, giving a relative standard deviation of
9.4 percent. This is within the precision objective of this measurement of
10 percent (Reference 4-1).
Results of the duplicate GC/MS injections are summarized in Table 4-2.
The relative standard deviations for all compounds quantitated were well
within the project precision objective of 50 percent for this measurement.
4-4
-------
TABLE 4-2. DUPLICATE GC/MS ANALYSIS RESULTS FOR THE
CATALYST OUTLET XAD-2 EXTRACT
Relative
standard
Run 1 Run 2 deviation
Compound (jig/train) (ug/train) (percent)
Naphthalene
Di-n-butyl phthalate
Bis (2-ethylhexyl)
phthalate
10
160
30
10
120
20
0
20.2
28.3
REFERENCE FOR SECTION 4
4-1. "Quality Assurance Plan for the Combustion Modification Environmental
Assessment," Acurex Corporation under EPA Contract 68-02-2160,
September 10, 1982.
4-5
-------
SECTION 5
SUMMARY
Field tests were performed in a lean-burn 1,500-kW (2,000-hp)
reciprocating internal combustion engine retrofitted with an ammonia-based
selective catalytic reduction (SCR) system for NOX reduction. Two series of
tests were performed: a comprehensive test program to characterize catalyst
inlet and outlet exhaust gas composition at a catalyst NOX reduction
performance target of 80 percent; and a 15-day exhaust monitoring program to
measure the catalyst performance under typical engine operation. Prior to
the test period, problems were experienced with the NHs control system,
specifically, the NOX analyzer and also the NH3 control valve.
NOX emission reduction during the 1-day comprehensive tests was
maintained relatively constant at about 80 percent using an NHs/NO molar
ratio of about 1.0. Catalyst inlet NOX levels from the four-stroke
turbocharged engine ranged between 2,200 and 2,600 ppm as measured at about
11 percent excess 02. At the catalyst outlet, NOX ranged from 330 to
560 ppm. NH3 carryover measured at the catalyst outlet ranged between 65 and
120 ppm (about 80 ppm average) using an extractive sampling system.
Continuous monitoring techniques suggested NHs carryover levels in the range
of 20 to 140 ppm (about 80 ppm average). Other emission measurements suggest
relatively minor effects of the catalyst on CO and particulate emissions.
Total cyanides increased from about 7 ug/dscm to 2.4 mg/dscm across the
5-1
-------
catalyst. Total organics (Cy+) decreased about 70 percent from 4.9 mg/dscm
to 1.5 mg/dscm. Analyses for volatile organics showed benzene and toluene as
the major compounds with catalyst outlet gas concentrations of about 920 and
250 pg/dscm, respectively. Semivolatile organic analyses showed a general
decrease of PAH compounds (naphthalene and phenanthrene) across the catalyst.
Outlet concentrations of these and other organics were generally below
0.4 ug/dscm (1.6 jig/Bhp-hr).
During the extended 15-day continuous monitoring of criteria gas
emissions, catalyst NOX reduction performance was maintained at about
80 percent. Brief periods of reduced catalytic performance were attributed
to engine load surges and an occasional malfunction in the NH3 injection
flowrate. NH3 carryover emissions at the catalyst outlet ranged from 0 to
about 150 ppm. Overall, the SCR system tested was found capable of
maintaining 80 percent NOX reduction with no significant environmental impact
apart from NH3 carryover of generally less than 100 ppm and cyanide
formation to 1.3 ppm.
5-2
-------
APPENDIX A
SAMPLING AND ANALYSIS METHODS
Emissions test equipment was provided by Acurex Corporation. Onsite
equipment included a continuous monitoring system for emissions measurements
of gaseous criteria pollutants; the SASS train for particulate mass,
semivolatile and nonvolatile organics; a VOST train by volatile organics; two
separate sampling trains for NH3 and HCN measurement; gas grab sampling
equipment for determining N20 emissions by laboratory gas chromatography, and
for validation of NOX measurements with EPA Method 7. The following sections
summarize the sampling and analysis equipment and methods used in the field
and laboratory.
A.I CONTINUOUS MONITORING SYSTEM
Acurex provided a continuous monitoring system modified to allow online
simultaneous NO, NOX, and NHs sampling capability alternatively at the inlet
and outlet of the catalytic reactor. Figure A-l illustrates a simplified
schematic of the gas conditioning and monitoring system. The monitoring
capability included Og, COg, CO (high and low concentrations), NO, NOX, NOX +
NH3, and TUHC. The heated sample gas was treated for moisture removal using
a permeation dryer. Simultaneous sampling of NO, NOX, and NH3 was achieved
by using two chemiluminescent analyzers. One was equipped with an unheated
molybdenum converter to prevent conversion of NH3 to NO in the sample gas and
one was equipped with a standard heated stainless-steel converter to convert
A-l
-------
Oll-ltu «lr
-D-CO
«Mt 10
(UMOIwrt
T« iMlrwwitl
Figure A-l. Schematic for continuous extractive sampling system.
A-2
-------
both N02 and NH3 to NO. NH3 emissions were calculated using the difference
in readings between the two analyzers. Table A-l lists the instrumentation
r
constituting the continuous monitoring and flue gas extractive sampling
system. A datalogger was used in addition to strip charts to record data
continuously.
A.2 SEMIVOLATILE AND NONVOLATILE ORGANIC EMISSIONS
Emissions of semivolatile and nonvolatile organics were sampled using
the source assessment sampling system (SASS). Designed for Level 1
\
environmental assessment (Reference A-l), the SASS collects large quantities
of gas and solid samples required for subsequent analyses of inorganic and
organic emissions.
The SASS, illustrated in Figure A-2, is generally similar to the system
utilized for total particulate mass emission tests (a high volume Method 5
train) with the exception of:
The addition of a gas cooler and organic sampling module
The addition of necessary vacuum pumps to allow a sampling rate of
2 1/s (4 cfm)
Particulate cyclones shown in Figure A-2 were not used for these tests
because of low particulate loading in the flue gas.
Schematics outlining the standard sampling and analytical procedures
using the SASS equipment are presented in Figures A-3 and A-4. The following
paragraphs briefly describe analytical procedures used in measuring organic
emissions.
Quantitative information on total organic emissions was obtained by gas
chromatography/flame ionization detector for total chromatographable organics
(TCO) and by gravimetry (6RAV) of sample extracts. Infrared spectroscopy
A-3
-------
TABLE A-l. CONTINUOUS MONITORING EQUIPMENT IN THE MOBILE LABORATORY
Instrument
NO
NOX
CO (1)
CO (2)
C02
S02
02
TUHC
Datalogger
Sample gas
conditioner
Strip chart
recorders
Principle of
Operation
Chemi luminescence
Nondi spersi ve
infrared (NDIR)
Nondi spersi ve
infrared (NDIR)
Nondi spersi ve
infrared (NDIR)
Pulsed
Fluorescence
Fuel cell
Flame ionization
detection (FID)
Electronic
Permeation
dryer
Dual pen analog
Manufacturer
Thermo
Electron
ANARAD
ANARAD
ANARAD
Thermo
Electron
Teledyne
Beckman
Acurex/
Autodata
Permapure
Linear
Instrument
Model
10 AR
500R
BOOR
AR500
40
400
10
E-46-SS
400
Range
0 to 2.5 ppm
0 to 10 ppm
0 to 25 ppm
0 to 100 ppm
0 to 250 ppm
0 to 1,000 ppm
0 to 2,500 ppm
0 to 10,000 ppm
0 to 1,000 ppm
0 to 1.0 percent
(10,000 ppm)
0 to 20 percent
0 to 100 ppm
0 to 1,000 ppm
0 to 5,000 ppm
0 to 10,000 ppm
0 to 5 percent
0 to 10 percent
0 to 25 percent
0 to 500 ppm
99 channels
10 scfm
0 to 10 mV
0 to 100 mV
0 to IV
0 to 10V
A-4
-------
Heated oven
filter
en
Stainless
steel
sample
nozzle
Stack T.C.
Organic module
Gas temperature T.C.
1/2" Teflon line
Stack
velocity
AP magneheliCi
gauges
1/2" Teflo
line
Isolation
ball valve
Stainless steel
probe assembly
Oven T.C
Sorbet)t cartridge
Heater controller
1
kol lector vessep
Imp/cooler trace
element collector
Coarse adjustment
Orifice All
magnehelic
gauge
Vacuum pumps
(10 ft3/mln each)
Impinger
T.C.
Ice bath
COO grams
silica gel
desicant
500 ml
0.2 H AgNOi
0.2 M (NII4)2
500 ml
30X
Heavy Mai 1
vacuum line
Note: T.C. = Thermocouple
Figure"A-2. Source assessment sampling train schematic.
-------
SAMPLE
rnunt WASH. ETC.
SORBENT CARTRIDGE
AQUEOUS CONOENSATE
FIRST 1MPINGER
ul
ui
at z
So -
-** «E°a 5
« ujS <
I *V £
* °1 s S
s *a 5 ui
t- CO U t-
« a u» a
i II * 5
x u c c Q
u a o O 3
^__<^sp!lT
-. *i ^x^
, *
\
/
SPLIT \
S GRAMS
^ AQUEOUS PORTION
N^ ORGANIC EXTRACT
i
C
> C
I I i
A
ii A al
1 PARR/ACID OIQESTION
1 SSMS
A
COMBINE
X
_/^~
a
§
BV AAS
SECOND AND THIRD
IMPINGERS COMBINED
TOTALS
S 2 S
K required, nmpl* should b. «t tiida for biological anatyin at this point.
Thn iitp it raquir^ TO dafin* (h« total maa of particulata catch. If th* ampta .«ca.oi 10% of th« teal eydon* and
dlt«r tampl. vMiqht procMd lo analym. If th. ampla it laii than 10% of th. catch, hold in rnmm.
Figure A-3. Flue gas analysis protocol for SASS samples.
A-6
-------
FLUE SOURCE
OPACITY
Figure A-4. Flue gas sample analysis protocol.
-------
(IR) and gas chromatography/mass spectroscopy (GC/MS) were used for
identification of organic functional groups and for determining polycyclic
organic matter (POM) and other organic species concentrations (the
semivolatile organic priority pollutants) in extract samples. Figure A-5
illustrates the organic analysis methodology used.
Passivation of the SASS train with 15 percent by volume HN03 solution
was performed prior to equipment preparation and sampling to produce
biologically inert surfaces. Detailed descriptions of equipment preparation,
sampling procedures, and sample recovery are discussed in Reference A-l and
will not be repeated here.
A.3 VOLATILE ORGANIC EMISSIONS
A volatile organic sampling train (VOST), shown schematically in
Figure A-6, was used to measure the low molecular weight volatile organic
compounds (boiling points ^110°C) in the flue gas according to the EPA
protocol (Reference A-2). The train consists of two organic sorbent traps
connected in series. The first trap contained ~1.6g of the porous polymer
Tenax-GC; 35/60 mesh. The second trap consisted of ~1.0g each of Tenax-GC
and petroleum-based charcoal. Prior to their use in the field, each trap was
conditioned to remove organic compounds. Conditioning consisted of baking
each trap at 190°C with a N£ purge for an 8-hr period. The traps were then
desorbed at 190°C directly into a GC/FID. If a trap showed no contaminant
peaks greater than 20 ng as benzene or toluene, it was considered ready for
sampling. The trap was then sealed at each end with compression fittings,
placed in clean, muffled culture tubes, and sealed in a metal can for
shipping.
A-8
-------
Organic Extract
or
Neat Organic Liquid
1
T
Analysis
Concentrate
Extract
«
K\
-------
'T' bore stopcock
Glass wool
participate
filter
Charcoal
backflush trap
Stack
(or test
system)
b
si
Thermocouple
insert port
Condensate
trap impinger
Empty Silica
impinger gel
Exhaust
Dry gas
meter
Figure A-6. Schematic of volatile organic sampling train (VOST).
A-10
-------
Before the field testing, the entire system was leak-checked at ~15 to
20-in. of vacuum. A leakage rate of 0.05 liter/min was considered
acceptable. Ambient air was drawn through a charcoal-filled tube to prevent
organic contamination while bringing the system back to ambient pressure.
One set of samples and a field blank were obtained for the test program.
The gas sample was obtained at the catalyst outlet (stock) location. A total
sample volume of 20 1 was taken over a 40-min period (0.5 1/min). Upon
completion of the test, the sample traps were removed from the train, sealed,
returned to their original culture tubes, and stored in a metal can on ice.
The VOST samples were analyzed by GC/MS according to the EPA VOST protocol.
Each pair of traps used was thermally desorbed and analyzed for the EPA
Method 624 (volatile) priority pollutants.
A.4 NH3 AND HCN SAMPLING AND ANALYSIS
NH3 and HCN were measured at the inlet and outlet locations of the
catalytic converter utilizing two separate sampling trains. Both trains were
similar to an EPA Method 6 train except that impinger solutions for NH3
absorption were acid based (0.1N HC1) and for HCN were caustic based
(0.1N NaOH) Concentrations of NH3 and HCN in solutions were determined in the
laboratory using approved wet chemical methods (HCN) of by specific ion
electrode (NH3) (Reference A-2).
A.5 N20 SAMPLING AND ANALYSIS ,
The stack gas grab samples were extracted into stainless-steel cylinders
for laboratory analysis for N20 using a sampling train illustrated in
Figure A-7. For analysis each sample cylinder was externally heated to 120°C
(250°F), then a 1-ml sample was withdrawn with a gas-tight syringe for
injection into the gas chromatograph (GC) equipped with an electron capture
A-ll
-------
I
(
I\J
0.7 \m sintered stainless-steel filter
l/4-1n. stainless-steel
probe
Teflon diaphragm pump
Pressure gauge
Inlet valve
.3
500-cm stainless-steel
sample cylinder
Ceramic Insulation
and heat tape
Outlet
valve
Thermocouple
Figure A-7. ^0 sampling system.
-------
detector (ECD). The GC column used was a 10 ft x 1/8 in. stainless-steel
column packed with 80/100 mesh chromosorb 101. The flow of nitrogen was
20 ml/min with the column kept at 45°C. Elution time for ^0 was
approximately 5 min.
A.6 NOX MONITOR CERTIFICATION SAMPLING AND ANALYSIS
Certification of the continuous NOX monitor was performed using the
standard EPA Method 7 equipment and protocols.
A-13
-------
REFERENCES FOR APPENDIX A
A-l. Lentzen, D. E., et al., "IERL-RTP Procedures Manual: Level 1
Environmental Assessment (Second Edition)," EPA-600/7-78-201,
NTIS PB293795, October 1978.
A-2. "Protocol for the Collection and Analysis of Volatile POHC's Using
VOST," EPA-600/8-84-007, NTIS P884-170042 March 1984.
A-3. "Methods for Chemical Analysis of Water and Wastes," EPA-600/4-79-020,
MTIS PB 297 686, March 1979.
A-14
-------
TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 REPORT NO.
EPA-600/7-86-014a
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE ANO SUBTITLE
Environmental Assessment of a Reciprocating Engine
Retrofitted with Selective Catalytic Reduction;
Volume I. Technical Results
i. REPORT DATE
April 1986
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
C. Castaldini and L. R. Water-land
8. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAME ANO ADDRESS
A cur ex Corporation
Energy and Environmental Division
P. O. Box 7555
Mountain View, California 94039
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3188
12. SPONSORING AGENCY NAME ANO ADDRESS
EPA, Office of Research and Development
Air and Energy Engineering Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final; 3-12/84
14. SPONSORING AGENCY CODE
EPA/600/13
15. SUPPLEMENTARY NOTES AEERL project officer is Joseph A. McSorley. Mail Drop 65.
919/541-2920. Volume II is a data supplement.
16- CT The report gives results of comprehensive emission measurements and
15-day continuous emission monitoring for a 1, 500 kW (2000 hp) gas-fired, four-
stroke turbocharged reciprocating engine equipped with an ammonia-based selective
catalytic reduction system for NOx control. Emission reductions were held at
about 80% using an ammonia/NO ratio of about 1.0. NOx levels at the catalyst inlet
ranged from 2,200 to 2, 600 ppm at an exhaust gas oxygen level of about 11%. NOx
levels at the catalyst outlet ranged from 65 to 120 ppm. The catalyst had relatively
minor effect on CO and particulate emissions, but increased total cyanides by 3
orders of magnitude (from 7 micrograms/dscm to 2.4 mg/dscm) across the cata-
lyst. Total organics decreased about 70%, from 4.9 to 1. 5 mg/dscm. Analyses
showed benzene and toluene as the major organic constituents in the catalyst exhaust
Polycyclic aromatics also decreased across the catalyst. The 15-day continuous
monitoring tests showed that the catalyst was generally able to maintain NOx reduc-
tions at about 80%. Departures from these levels occurred only during brief load
surges and ammonia flowrate spikes.
17.
KEY WORDS ANO DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATl Field/Croup
Pollution
Assessments
Reciprocating Engines
Gas Engines
Catalysis
Reduction (Chemistry)
Ammonia
Nitrogen Oxides
Pollution Control
Stationary Sources
Environmental Assess-
ment
Selective Catalytic Re-
duction
13B
14B
21G
07D
07B.07C
g. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report I
Unclassified
21. NO. OF PAGES
69
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 C9-71)
A-15
------- |