Engine Emissions Stack Testing
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Engine Emissions Stack Testing and Analyzer Workshop
New Air Regulations, Test Requirements and Test Strategies
Jeff Thomason, QSTI
P j t Di tProject DirectorTRC
9225 U.S. Highway 183 SouthAustin, Texas512/243-0202
Topics of Conversation
Federal Regulations Subpart JJJJ Subpart ZZZZ Greenhouse Gases Measuring Hydrocarbons EPA Methods 1 and 1A VOCs, HAPs, & Hard Stuff
EPA National Stack Testing Guidelines
Goals Improve uniformity on how tests are
conducted Improve coordination between EPA and Improve coordination between EPA and
state/local agencies Enhance EPA oversight of state/local
programs http://www.epa.gov/ttn/emc/guidlnd/g
d-050.pdf
EPA National Stack Testing Guidelines
Regulated units include Reciprocating Internal Combustion
Engines NSPS Turbines NSPS Turbines Title V and PSD Permitted Sources
Title V: 10 tons / 25 tons qualifiers
Adopted by State Agencies for Construction &
Operating Permits
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests1. Time Frame
a facility that has not completed a stack test within the requisite time frame would be in violation of the requirement to stack test
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests2. Test Waivers-NO WAIVERS even on identical NO WAIVERSeven on identical units unless:
in service at the same facilityoperated/maintained the same wayemissions applicable standard
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests3. Notification of Stack Tests
Timing and content of notification Must provide notification of delays
as soon as possibleNotification is not necessary if the test
is for the facilitys own benefitHOWEVER
EPA National Stack Testing Guidelines
IF YOU FAIL (and are a Title V source)
YOU MUST REPORT THE FAILURE AND SUBMIT THE DATA TO THE PROPER AGENCY
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Test Protocol should be submitted
www.epa.gov/compliance/assistance/air/index.htmlhtml
Tell the agency which unit, where, why, when, and who
Explain the test matrix Describe process data and load determination Identify the test methods, and explain any request
for deviations
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Observation of Stack Tests
Will they come? Why should it matter? If notification wasnt timely then the
resulting test data may be rejected and a new stack test required.
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Representative Testing Conditions Generally, test at the maximum load condition y,
the source is designed for If you do not operate at that level, test at
where you do operate but you must DOCUMENT historical trends
Different state/local agencies have their own criteria
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Stoppages
If you stop because you might fail, you y p y g , ywould be considered in violation of both the requirement to test and the permit condition
If you have to stop because of equipment failure, severe weather and/or safety, complete the run thats in progress if possible and fully document the reasons for stoppage
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Postponements
Considered in same way as stoppagesy pp g the delegated agency should carefully
scrutinize the circumstances surrounding the postponement to determine whether the facility was in violation of the underlying emission limitationsand postponed to avoid a documented violation.
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Reports
Should be detailed enough to assess Should be detailed enough to assess compliance with the regulatory requirements
www.epa.gov/ttnemc01/guidlnd/gd-043.wpd
Submit as soon as possible-most states have specific timelines-Typically 30, 45, or 60 days. EPA reports have 60 days
EPA National Stack Testing Guidelines
Section VI-Conduct of Stack Tests Rounding of Significant Figures
Report the same number of figures that Report the same number of figures that are in your permit
If its less than 5, round down. If its more than 5, round up
If its exactly 5 followed by zeros, round up if the number is odd. Leave it if the number is even
Subpart JJJJ
QUAD JQUAD J
Subpart JJJJ
New Source Performance Standards (NSPS) 40 CFR 60, Subpart JJJJ
National Emission Standards for Hazardous Air Pollutants (NESHAP) 40 CFR 63, Subpart ZZZZ (RICE MACT)
Published January 18, 2008 Affects ALL new, reconstructed or modified
IC engines Standards get more stringent in 2010/2011
depending on engine type/size
Subpart JJJJ
Technology Basis Rich Burn: NSCR Lean Burn: combustion based controls
(Low Emission Combustion)
Pollutants and Emission Limits
(Low Emission Combustion) Emission Limits for NOx, CO, VOC
VOC as defined includes HCHO, but notincluded for this subpart
NOx + HC included for some smaller engines
Subpart JJJJ
Non-Emergency Engines 100hp
Subpart JJJJ
Non-Emergency Engines 100hp
Subpart JJJJ
Non-Emergency Lean Burn Engines 500hp
Subpart JJJJ
Non-Emergency Engines (except LB) 500 hp
Pollutants and Emission Limits
MFGDATE NOx CO VOC NOx CO VOC
7/1/2007 2.0 4.0 1.0 160 540 867/1/2010 1.0 2.0 0.7 82 270 60
g/bhp-hr ppmv @ 15% O2
Subpart JJJJ
Natural Gas Fired Lawn Mower Engines 25hp100
Pollutants and Emission Limits
MFGDATE CO
7/1/2008 6.53.8HC + NOx
g/bhp-hr
Subpart JJJJ
Reconstructed or modified engines Applies to EXISTING UNITS (6/12/06)
Pollutants and Emission Limits
R/M ppmv @ 15% O2g/bhp-hr
25 hp must meet new engine standard New engines subject to JJJJ that are R/M
must meet JJJJ standards
R/MDATE NOx CO VOC NOx CO VOC
6/12/2006 3.0 4.0 1.0 250 540 86(non emgy,
Subpart JJJJ
What is new? Date the engine was ordered is the day
construction starts
If ordered on or before 6/12/06, engine is EXISTING and Quad J engine is EXISTING and Quad J doesnt apply
If ordered after 6/12/06 but MANUFACTURED before, Quad J doesnt apply
If ordered after and manufactured after 6/12/06, Quad J DOES apply
Subpart JJJJ
What is Modified? Physical or operational change to an
existing facility that results in an increase in the emission rate
An existing facility is affected for each pollutant with a standard and an emission rate increase
Exemptions include installation of pollutant control devices
Compliance required within 180 days of the change
Subpart JJJJ
EPA Revisions proposed 6/8/10
Proposed rule includes new definition for reconstruction The fixed capital cost of new components
exceeds 50% of the cost of an entirely new facility in todays $$$
Engineering, transportation, installation, start-up, etc. costs must be INCLUDED
Must be feasible
Subpart JJJJ
EPA Revisions proposed 6/8/10 New definition: For purposes of
reconstruction, an existing t ti i i d fi d stationary engine is defined as
including those components mounted to or within the cylinder block, the engine housings, and engine mounted components, but excluding ancillary components such as external cooling for fuel supply.
Subpart JJJJ
EPA Revisions proposed 6/8/10 Draws narrower box around the equipment
considered in cost calculations than historical NSPS determinations and historical NSPS determinations and excludes necessary engine components
Mobile source paradigm (mounted on engine) does not properly consider stationary source scenario Comments stressed that components
inherent to engine operation (e.g., cooling) should be included in the costs
Subpart JJJJ
EPA Revisions proposed 6/8/10
Date of manufacture definition includes:Reconstructed engines are assigned a new date of manufacture if the crankshaft is removed as part of the reconstruction or if the the crankshaft is removed as part of the reconstruction or if the fixed capital cost of the new and refurbished components exceeds 75 percent of the fixed capital cost of a comparable new engine (see the definition of "reconstruct"). An engine that is produced from a previously used engine block does not retain the date of manufacture of the engine in which the engine block was previously used if the engine serial number was removed (or the engine otherwise loses its identity), or the engine is produced using all new components except for the engine block. In all these cases, the date of manufacture is the date of reconstruction or the date the new engine is produced.
Subpart JJJJ
What about Relocation? In and of itself, relocation does NOT
trigger modification or reconstruction and are not subject t NSPS to NSPS (unless manufactured after the earlier dates)
Evaluate whether reconstruction or modification occurs
EPA says changes in control equipment or method of operation can trigger applicability
Subpart JJJJAdditional stuff for relocated
engines Operators must understand changes,
if any, to relocated engines Has engine been modified i e rich to Has engine been modified, i.e. rich to
lean? Was engine rebuilt or was major
maintenance or repair completed?
Ownership changes does not make an engine new
Operators ARE responsible for ensuring compliance of relocated engines
Subpart JJJJ
Engine Rating (40CFR1039.140)An engine configurations maximum
engine power is the maximum brake power point on the nominal power curve power point on the nominal power curve for engine configuration
o Its manufacturer nameplate rating without consideration of elevation, etc.
o RICE MACT is site rated.
Subpart JJJJ
THREE ENGINE TYPES1. Certified Engines
2. Non-Certified Engines2. Non Certified Engines
3. Certified engines operating as non-certified engines
Subpart JJJJ
CERTIFIEDo manufacturers test the engine
according to a defined operating cycle to validate compliance
o Full Load tests requiredo High Load engines- 100% & 75%o ISO 8178, D-1 Cycle-100/100% plus
30%/100%; 50%/75%; 20%/50%o DO NOT require compliance tests
under JJJJ, but many states require it
Subpart JJJJ
CERTIFIEDo MFG insures compliance for certified
emissions life-5000 operating hours or lessMFG O&M MUST be followed by o MFG O&M MUST be followed by operator
o Operators must comply with the emission standards for the life of the engine
Subpart JJJJ
NON-CERTIFIEDo Requires an initial performance testo Maintenance plan & recordso Periodic tests for engines >500 Hpg p
o Every 8760 hours or once per 3 years
o No further tests for engines< 500 HPo Unless major repair or rebuild
(40CFR60.4243(f))o Major repair or rebuild is not defined
Subpart JJJJ
CERTIFIED OPERATING AS NON-CERTIFIED
o Operators can opt not to follow MFG O&M or may be precluded y p(fuel quality)
o Same requirements as non-certified
o Engines
Subpart JJJJ
PERFORMANCE TESTSo Subpart REQUIRES compliance
demonstration for NOx, CO, VOCo Applies to modified/reconstructedo Applies to modified/reconstructedo Applies to Non-Certified Engineso Applies to Certified operating as
Non-Certified 100 Hp
Subpart JJJJ
PERFORMANCE TESTSTest Timeline
o Non-certified > 25 Hp: within 60 days of max production but no later than 180 days of startuplater than 180 days of startup
o CONC 100 Hp: within 1 year of start up
o Subsequent tests for both >500 Hp every 8760 hrs/3 years
o After rebuild or major repair for engines >500 Hp
Subpart JJJJ
PERFORMANCE TESTSTest trigger for rebuild/major
repair not currently well definedo Operators burden to determine if
requiredo DOCUMENT THE DECISION
Subpart JJJJ
PERFORMANCE TESTSo Three test runs of at least one
houro Operate at 100 10%o Operate at 100 10%o Measure/collect at outlet of
any control deviceso Dont test during start up,
shut down or malfunction
Subpart JJJJ
PERFORMANCE TESTSo Measure NOx, CO, VOC, O2
and moistureo If complying with g/Hp-hr
o Exhaust gas flow rateo Hp
Subpart JJJJ
PERFORMANCE TESTSo EPA Reference Methods
o NOx-7Eo CO-10o O2-3Ao VOC methods to come
Subpart JJJJ
PERFORMANCE TESTSo Portable Analyzer Methods
o ASTM D6522o Administrator approved alternative portable analyzer method
o ASTM D6420-99 (GC/MS)
Subpart JJJJ
PERFORMANCE TESTSo Fourier Transform Infrared
Spectroscopy (FTIR)o EPA RM 320o ASTM D6348-03
o Wet or Dry Basis?o So?
Subpart JJJJ
PERFORMANCE TESTSo VOC Test Issues
o Does not include methane (CH ) th (C H )(CH4) or ethane (C2H6)
o Does not include HCHOo Reported as ppmv Propaneo Two approaches- additive or subtractive
Subpart JJJJ
PERFORMANCE TESTSo Additive Methods
o Quantify and sum applicable i di id l HC iindividual HC species
o Can be beneficial for NG fired sources due to high CH4/C2H6composition
Subpart JJJJ
PERFORMANCE TESTSo Subtractive Methods
o Difference between THC and CH + C HCH4 + C2H6
o Subtracting two very similar numbers can cause error
o Shouldnt be a problem if C2H6is
Subpart JJJJ
PERFORMANCE TESTSo Additive Methods
o Gas Chromatographyo FTIR
Presurvey requiredo Presurvey requiredo INGAA and EPA discussion of one-time
presurvey to define VOC species for NG-fired ICEs
o Option to adjust aldehydes and other oxygenated HC for 25A response factors
Subpart JJJJ
PERFORMANCE TESTSo Subtractive Methods
o EPA 25A +Gas Chromatographyo VOC = THC (CH + C H )o VOC = THC (CH4 + C2H6)o Poor response to HCHO but not a VOCo Must be performed very well
o EPA 25A with a methane cuttero Dual channel FIDo Possible high bias if high C2H6
Subpart JJJJ
PERFORMANCE TESTSo Exhaust Moisture
o VOC measured hot & weto Mass emissions are dryo Everything must be on same basis
Subpart JJJJ
PERFORMANCE TESTSo Exhaust Flow
o EPA Method 2 Pitot Tubeo EPA Method 19 o EPA Method 19
o Preferred due to pulsating flowo Must have
o Fuel Flow rate (orifice cal!)o Fuel Composition (not last
years)
Subpart ZZZZ
Reciprocating Internal Combustion Engines (RICE), Maximum Available Control Technology (MACT)
Subpart ZZZZ (RICE MACT) is designed to regulate hazardous air pollutants (HAPS). In the case of reciprocating engines, the surrogates are Carbon Monoxide (CO) and Formaldehyde (HCHO).
Subpart ZZZZ
RICE MACT REVISITEDo Final Rule amended 8/20/10o EFFECTIVE DATE IS 10/19/10o Three years (10/19/13) for newly o Three years (10/19/13) for newly
affected engines to complyo Now includes all engines except
existing major source lean burns >500 Hp
o These will be addressed in 2012
Subpart ZZZZ
RICE MACT REVISITEDo With proposed amendments,
ALL new and reconstructed units are affected regardless units are affected regardless of size
o Most units comply based on NSPS
o Original RICE MACT rule applies as appropriate
Subpart ZZZZ
RICE MACT REVISITEDo Major HAP source emits
o 10 tons/year of a single HAPo 25 tons/year of cumulative HAPSo 25 tons/year of cumulative HAPSo HCHO typically drives major source
status for sites with multiple RICEo If emissions reduced below the
threshold prior to the regulatory date, facility is an area source.
Subpart ZZZZ
Emission Limits:Major Sources
o SI RICE < 100 Hpo No numerical emission standards
o 2 Stroke Lean Burn (2SLB) 100 HP 500o CO concentration 225 ppmvd @ 15% O2
o 2 Stroke Lean Burn (2SLB) 500 Hpo Reduction of CO across an oxidation catalyst
58 %o CO concentration 225 ppmvd @ 15% O2
Subpart ZZZZ
Emission Limits:Major Sources
o 4 Stroke Lean Burn (4SLB) 100 HP 500CO t ti 47 d @ 15% Oo CO concentration 47 ppmvd @ 15% O2
o 4 Stroke Lean Burn (4SLB) 500 Hpo Reduction of CO across a catalyst 93%o HCHO concentration 14 ppmvd @ 15% O2
Subpart ZZZZ
Emission Limits:Major Sources
o 4 Stroke Rich Burn (4SRB) 100 HP 500HCHO t ti 10 3 d @ 15% Oo HCHO concentration 10.3 ppmvd @ 15% O2
o 4 Stroke Rich Burn (4SRB) 500 Hpo Reduction of HCHO across a catalyst 76%o HCHO concentration 350 ppbvd @ 15% O2
Subpart ZZZZ
Emission Limits:Area Sources
o 4 Stroke Lean Burn (4SLB) 500 HpR d ti f CO t l t 93%o Reduction of CO across a catalyst 93%
o CO concentration 47 ppmvd @ 15% O2
o 4 Stroke Rich Burn (4SRB) 500 Hpo Reduction of HCHO across a catalyst 76%o HCHO concentration 2.7 ppmvd @ 15% O2
Subpart ZZZZ
Test Frequency :Major Sources
o SI RICE < 100 Hpo Do not have to conduct any performance test.o Must develop a maintenance plan that specifies how the
management practice will be met and provides to the extent practicable for the maintenance and operation of the engine in a manner consistent with minimizing emissions.
o 2 Stroke Lean Burn (2SLB) 100 HP 500o Must conduct an initial performance test to demonstrate
that they are achieving the required emission standards.o If oxidation catalyst is changed, conduct new emission test.
Subpart ZZZZ
Test Frequency:Major Source
o 2 Stroke Lean Burn (2SLB) 500 Hpo Must conduct an initial performance test to demonstrate
that they are achieving the required emission standards.o Semi-annual testing until demonstrating compliance for
two consecutive tests, then annual testing.o If the results of any subsequent annual performance test
indicate the engine is not in compliance or you deviate from any of your operating limitations, you must resume semiannual performance testing.
o If oxidation catalyst is changed, conduct new emission test.
Subpart ZZZZ
RICE MACT REVISITEDo Oxidation catalyst temperature
monitored continuouslyo Catalyst inlet temperature
450F d 1350Fo 450F and 1350F
o Pressure drop across catalyst measured monthly
o P changes no more than 2 H2O from baseline
Subpart ZZZZ
RICE MACT REVISITEDo Performance tests
o Initial, within 180 days of compliance date
o Semiannual, goes to annual after 2 consecutive compliant tests (comes back if you fail a test)
o Catalyst change performance testo Re-establish P baseline
Subpart ZZZZ
RICE MACT REVISITEDo Performance tests
o Test at 100% 10%o DOCUMENT THE LOAD- define whato DOCUMENT THE LOAD define what
load is and how it was measuredo Measure inlet temperatureo Measure catalyst pressure dropo Must use approved methods
Subpart ZZZZ
RICE MACT REVISITEDo One New Source Subcategory
o N/R 4SLB @ MAJOR HAP SOURCEo 250 hpo 250 hp
o Requires catalytic controlo Requires catalyst inlet temperatureo Requires P monitoringo Requires Performance Testso Requires all reporting & recordkeeping
2010 NESHAP Revisions
NESHAPo National Emission Standards
for Hazardous Air Pollutantso Also known as MACT
o Maximum Achievable Control Technology
2010 NESHAP Revisions
Emission Limits:o Proposed limits for existing engines more
stringent that limits for new major source engines subject to RICE MACT
o Startup, shutdown and malfunction (SSM) emission limit:
o Start up must be limited to 30 minuteso EPA states that shutdown emissions should
be the same as normal operation (including catalytic control)
o Limits apply under all conditions and for all fuel types
2010 NESHAP Revisions
4SLB Emission Limits:o CO: 47 ppmv @ 15% O2 or 93% Reduction
o Doable for catalyst equipped LB
o Significant debate ongoing about EPA methodology
2010 NESHAP Revisions
4SRB Emission Limits:
o Major Source HCHO: 10.3 ppmv for 100 -500 Hp
o Area Source HCHO: 2.7 ppmv OR 76% reduction for >500 Hp
o Significant debate ongoing about EPA methodology
2010 NESHAP Revisions
2SLB Emission Limits:
o Major Source CO: 225 ppmv @ 15% O2 for 100 500 Hp
o MUST be met at ALL LOADSA b i t l t ?o Are we buying catalysts?
o Area Source: Management Practices for all regardless of Hp
o Implications unclear for 2012 Review
Green House Gas Emissions
Its here:o NG GHGs: CO2, CH4, N2Oo Engine exhaust CO2 and CH4
account for about 20% of GHG emissions at compressor stations
o Vented and fugitive emissions are ~30-70% of gas transmission emissions
o Mandatory Reporting in Place
Volatile Organic Compound Test Methods
Key difference in sampling is all VOC are sampled hot and wet vs. dry
Non-Methane, Non-Ethane Non Methane, Non Ethane Hydrocarbons
THC-Method 25A VOC-Method 18 (GC/FID) FTIR
VOC Testing
EPA Method 25A-Total Hydrocarbons by FID All THC measured-calibration basis
either methane or propane Mathematical calculation of VOC from
THC-THC in exhaust is reflection of unburned fuel
Methane cutter can give VOC contribution
Insensitive to HCHO
VOC TestingEPA Method 18-Gas Chromatographyo Speciation of hydrocarbons by
GC/FIDo Time intensiveo Time intensiveo QA/QC is vital to regulatory acceptanceo Tedlar bag and off site analyseso On site, direct interface sampling
VOC Testing
EPA Method 320-FTIR Can see most everything at
once except O2onceexcept O2 Requires long path length analytical cell Real time results Can add significantly to cost of testing Calibration technique
Where Does HCHO Come From?
If theres O2 in the exhaust, there can be HCHO
Very little formation in Rich Burn E iEngines
Did we shoot ourselves in the foot with lean charge engines to reduce NOx?
Have a catalyst? Prepare to test!
Formaldehyde (HCHO) Test Methods
CO IS A TREND INDICATOR FOR FORMALDEHYDE
FTIR-real time data, a bit pricey EPA Method 320, ASTM D5348,
Acetylacetone-much less expensive Precision increases with length of test
run EPA re-promulgatged Method 323 with
August 2010 revisions
Formaldehyde (HCHO) Test Methods
Best Choice for a reasonable budget:EPA Method 25A with a Methane Cutter-
VOCEPA Method 323-HCHO
Near Real time ResultsNear Real time ResultsShow trendsShow trendsDONT SAMPLE HCHO FROM A DROP TUBE!DONT SAMPLE HCHO FROM A DROP TUBE!
Other HAPS of Primary Interest
Acrolein- C3H4OTough to sample for, no published method weve
tried completely meets the objectives:i i-inexpensive
-repeatable -straightforward analyses
Test methodology will involve collection in impingersRatio somewhere around 30:1 HCHO to C3H4O
EPA Methods 1 and 1A
Tell you where to sample for velocityBased on the diameter and the configuration
of the stackSpecifies the number of traverse points to
use for velocity measurementsCan specify the measurement location for
emission concentrationsEPA has exempted stacks
EPA Methods 1 and 1A
AUPSTREAM
2 preferred
0 5 minimum
B
0.5 minimum
DOWNSTREAM
8 preferred
2 minimum
EPA Methods 1 and 1A0.5 1.0 1.5 2.0 2.5
10
20
30
40
50
24 or 25*20
1612
8 or 9*
stack diameter 12-24 in
stack diameter > 24 in
Duct diameters upstream from flow disturbance (Distance A)
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*Larger number forrectangular stacks
P a r t i c u l a t e T raverses
B
ADisturbance
Disturbance
MeasurementSiteNumber of
traverse points is based on
upstream and 2 3 4 5 6 7 8 9 10
0
Duct diameters downstream from flow disturbance (Distance B)
M
0.5 1.0 1.5 2.0 2.5
2 3 4 5 6 7 8 9 100
10
20
30
40
50
1612
8 or 9*
stack diameter 12-24 in
stack diameter > 24 in
Duct diameters downstream from flow disturbance (Distance B)
Duct diameters upstream from flow disturbance (Distance A)
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*Larger number forrectangular stacks
N o n - P a r t i c u l a t e T raverses
B
ADisturbance
Disturbance
MeasurementSite
downstream distance (in
stack diameters)
from the flow disturbance
EPA Methods 1 and 1A
Number of traverse points
is based on upstream and
24 point layout
downstream distance (in
stack diameters)
from the flow disturbance 12 point layout
Make it Easy on YOURSELF
Too much communication is almost enough
Clearly define your test objectives Involve Gas Control on Day One Prepare a reasonable schedule with time
for things to not go perfectly
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