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PB82-188699
Sulfate and Particulate Emissions from In-Use
Catalyst Vehicles: Regulated/Unregulated
Emissions and Fuel Economy
-New York State Dept. of Environmental
Conservation, Albany
Prepared for
Environmental Protection Agency
Research Triangle Park, NC
ttOlor Vehicle Emission Lab
LIBRARY
Dec 79
U.&. Department of Commerce
National Technical Information Service
-------
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 MISCELLANEOUS REPORTS series. This
series is reserved for reports whose content does not fit into one of the other specific
series Conference proceedings, annual reports, and bibliographies are examples
of miscellaneous reports.
EPA REVIEW NOTICE
This report has been reviewed by the JJ S. Environmental Protection Agency, and
approved for publication Approval does not signify that the contents necessarily
reflect the views and policy of the Agency, 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 Information
Service. Springfield. Virginia 22161.
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EPA-600/9-79-047
December 1979
Sulfate and Participate Emissions
From In-Use Catalyst Vehicles:
Regulated/Unregulated Emissions
and Fuel Economy
by
R.E Gibbs. G P. Wotzak. S M. Byer, and N P. Kolak
Division of Air Resources
Automotive Emissions Evaluation
New York State Department of Environmental Conservation
50 Wolf Road
Albany. New York 12233
Grant No. R803520-01
Project Officer Frances Duffield
Environmental Criteria and Assessment Office
Research Triangle Park, NC 27711
Preoared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Office of Health and Environmental Assessment
Environmental Criteria and Assessment Office
Research Triangle Park. NC 27711
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DISCLAIMER
This report has been reviewed by the Environmental Criteria and
Assessment Office, U.S. Environmental Protection Agency, and approved for
publication. Approval does not signify that the contents necessarily
reflect the views and policies of the U.S. Environmental Protection Agency,
nor does mention of trade names or commercial produces constitute
endorsement or recommendation for use.
11
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FOREWORD ; .
To .issess tlie effects of pollution on thr environment and the public
health, a broad range of scientific and technical information is needed.
This means that the Environmental Protection Agency must carry out
. activities simultaneously on several fronts, including the measurement,
analysis, and precise characterization of the pollutants invading the
--environment, as well as the evaluation of the varied and oilen complex
biological effects of these pollutants. By critically .reviewing ar.d
interpreting such information, the Environmental Criteria and Assessment
Office of EPA provides a scientific basis for decisions on the regulation
of pollutants that may affect the environment or the public health.
this report presents- the results of a study on the pollutant emissions
and fuel economy of selected cars over a two and one-half year period. In
focusing on catalyst-equipped vehicles operated under "real world" conditions,
. this study attempts to provide information needed to accurately assess a
1' number of pollution problems associated with the use of automobiles.
'"i ' \
V ' : \ " \
'. ' \ Lester D. Grant \
\ \ ' - Director.
\ \ Environmental Criteria and
\ Assessment Office-
Jin
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ABSTRACT
An emissions and fuel economy study of 56 catalyst cars in consumer use
and maintenance has been performed by repeated testing of the cars over a two
and one-half year period. This report summarizes analyses of the data base,
and includes results on i^.le CO levels, mass emissions of HC, CO, NOX, sulfate.
S02 and total particulate; total particulate elemental analyses, catalyst
activity, and fuel economy. Test cycles used were the 1975 FTP, one-hour 50 mph
cruise, Congested Freeway Driving Schedule, Highway -Fuel Economy Test, and idle,
30 and 50 mph cruise for catalyst activity tests. Fuel economy data for over-
the-road driving are also presented from on-board totalizing fuel and engine
hour meters on each car.
Idle CO indicative of naladjuct«?d carburetors (> 1%) was found to cor-
relate with FTP CO emissions, purge of stored sulfur in the form of S02 from
catalysts, and decreases in catalyst activity at idle in comparison to 30 and
50 mph activity results. Particulate sulfate emissions accounted for only 3.7%.
of fuel sulfur for the 256 CFDS tests in the data base. Over-the-road fuel
economy was most closely represented by the FTP (city) value.
i
i
iv
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CONTENTS
Disclaimer ii
Abstract ill
Figures ........ ...... v
Tables viii
Abbreviations and Conversions ................. x
Acknowledgements ........................ xi
1. Introduction ..................... 1
2. Conclusions ...................... 6
3. Regulated and Sulfate remissions 8
4. Fuel Economy 24
5. Characterization of Particulate Emissions ...» ,. . . 40
6. Catalyst Activity Tests ..* ........ 57
7. Sulfur Dioxide Emissions ..i. ........... 64
8. Experimental Procedures and F Jipment ......... 72
References ........... ....... 100
Appendix A 1Q4
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FIGURES
Number Page
1 Mileage Test Point Roster. ............... 4
2 Mileage Accumulation Trends for HC Emissions ........... 12
3 Mileage Accumulation Trends for CO Emissions and
Mileage Accumulation Trends for Idle CO. ............ 13
4 Comparison of Idle CO and FTP CO Trends. ............. 15
TJ Mileage Accumulation Trends for NOX Emissions 17
6 Mileage Accumulation Trends for SO^ Emissions. .......... 18
7 FTP, CFDS, HFET Driving Schedules 26
8 Fuel Economy by Test Mode. .................... 28
9 Fuel Economy by Test Mode: Chrysler 225 CID 1-6 29
10 Fuel Economy by Test Mode: Chrysler 313 CID V-8 30
11 Fuel Economy by Test Mode: fiuick 350 < ID V-8 31
12 Fuel Economy vs. Mileage Accumulation, Car #2. .......... 32
i
13 Fuel Economy vs. Mileage Accumulation, Car #19 ..... 32
14 Fuel Economy vs. Mileage Accumulation, Car #25 .......... 32
15 Mileage Accumulation Trends for Carbon Balance Fuel Economy. ... 33
16 Seasonal OTR Fuel Economy. .'................... 34
17 Seasonal OTR Vehicle Speed '. 35
18 Cumulative Frequency Distribution OTR Vehicle Speed 37
19 Seasonal OTR Fuel Economy for Control Vehicle 38
M Seasonal OTR Vehicle Speed for Control Vehicle 39
vi
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FIGURES
tlumber Page
21 Sulfatc Emissions for Successive CFDS Cycles:
Monolith, no air pump. ..................... 41
22 Sulfatc Emissions for Successive CF^,- . /c-les:
Monolith, air pump .........
23 Sulfate Emissions for Sur-o^sivo iJFDS Cycles: Beaded,
no air pump. ...............««««««« 41
24 Fuel Analyses, Three Month Running Averages. ........... 44
25 Frequency Distribution of Particulate Bromine Emissions. ..... 49
26 Frequency Distribution of Particulate Lead Emissions ....... 49
27 Frequency Distribution of Particulate Zinc Emissions ...... . SO
28 Frequency Distribution of Particulate Copper Emissions ...... 50
29 Frequency Distribution of Particulate Iron Emissions ....... 51
30 Frequency Distribution of Particu'ate Sulfur Emissions ...... 51
31 Frequency Distribution of Particulate Calcium Emissions. ..... 52
32 Frequency Distribution of Particulate Phosphorous Emissions. ... 52
33 Frequency Distribution of Particulate Aluminum Emissions ..... 53
34 Frequency Distribution of Particulate Manganese Emissions. .... 53
35 Frequency Distribution of Percent Particulate Sulfur Recovery. . . 54
36 Frequency Distribution of Percent Particulate Lead Recovery. ... 54
37 Frequency Distribution of Percent Particulate Manganese Recovery . 55
38 Purge of S02 from Catalyst ......... ........... 66
39 SO 2 Purge Fractions by Idle CO Level: 50 mph cruise ....... 67
40 SO 2 Purge Fractions by Idle CO Level: CFDS. ........... 68
41 OTR Fuel Meter Installation ............. . ...... 75
42 Collection of Tank Fuel Samp-le ........... ....... 75
43 Vehicle Check-In ... ...................... 77
vi i
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FIGURES
I i
Number Page j 1
44 Vehicle Check-In Log Sheet 78 j
4? Car Mover Operation 79 ;,
h
46 Before/After Catalyst Sample Ports 79 j
47 Emissions Test Bay ................ 80
48 Dynamometer, Cooling Fans 81
49 Exhaust Sampling Equipment .................... 81
50 Schematic of Exhaust Handling and Particulate Sampling System. . . 83
51 Particulate Sample Probes. ... ........... 84
52 Oxygen in Raw Exhaust Sample System. ........ 86
53 SO2 Measurement System ........ 87
54 S02 Electronic Integration Switching System. ........... 88
55 Microbalance for Particulate Mass. ................ 91
56 BCA Apparatus Set-Up ....................... 93
57 Schematic for Automated BCA Analysis of Sulfate. ......... 94
58 XRF System for Particulate Analysis. ............... 95
59 Comparison of Total Particulate Emissions for Two Probes ..... 97
60 Comparison of 1C and BCA Sulfate Analysis ...« 98
61 Comparison of 1C and XRF Sulfur Analysis 99
viii
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TABLES
Numbc r Page
1 Test Croup Roster. 3
2 Classification of Cars and Tests 5
3 Average Emission Results by Car. ................. 9
4 Average Emission Results by Mileage Intervals. .......... 10
5 CO Trends by Mileage Accumulation. ................ 16
6 Average Emission Results, All Tests, All Manufacturers 19
7 Average Emission Results, General Motors Vehicle Tests 20
8 Average Emission Results, Ford Vehicle Tests ........... 21
9 Average Emission Results, Chrysler Vehicle Tests ......... 22
10 Tests Grouped by Emission Cut Points 23
11 Average Fuel Economy from Test G^oup Vehicles. .......... 25
12 Test Mode Characteristics 24
13 Sulfate Emissions as Percent of Fuel Sulfur Recovery .. 43
14 Total Particulate Emissions by Car ................ 45
15 XRF Detection Limits * * *'i ^7
i
16 Average XRF Elemental Emissions by Car '......... 48
17 Total Particulate Subclassification. .... 56
18 Catalyst Activity Measurements at Steady State: Idle 58
19 Catalyst Activity Measurements at ?-.cady State: 30 mph. ..... 59
20 Catalyst Activity Measurements at Steady State: 50 mph 60
IX
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TABLES
Number Page
21 Before/After Catalyst Measurement Comparison. ........... 61
22 Fuel Sulfur Recovery 69
23 Data List For Each Emissions Test 73
24 Typical Test Day 74
25 Exhaust Gas Measurement Instrumentation .............. 85
26 Computer Output for Typical Emissions Test. ............ 105
27 Computer Output Parameter List. .................. 106-7
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LIST OF ABBREVIATIONS
FTP -- (1975) Federal Test Procedure
CFDS Congested Freeway Driving Schedule, also known as S-7, SET-7,
CUE
HFET -- Highway Fuel Economy Test:
OTR Over.the-road
CVS Constant volume sampler
XRF x-ray fluorescence
EGA Barium chloranilace
k -- thousand (as in 5k miles = 5,000 miles)
1C Ion Chromatograph
AEL Automotive Emissions Laboratory, NYS Dept. of Environmental
Conservation, Latham, NY
CID Cubic inch displacement
S sulfur
mi -- mile(s)
hr hour(s)
km kilometer
g gram
mg milligram
uS micro gram
mpg » miles per gallon
1 liter
mm ~ millimeter
nm nanometer
CONVERSIONS
to convert from to multiply first column unit by
mi km 1.6
mi/hr km/hr 1.6
g/mi g/km 0.625
rag/mi . mg/km 0.625
mpg km/1 0.421
gm/gal gm/1 0.264
xi
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ACKNOWLEDGMENTS
Project Officer Vandy DuffieId's dedicated assistance contributed to this
study from its inception to conclusion, and is gratefully acknowledged.
Analysis of fuel samples was performed by Bob Jungers and the staff of the
Source, Fuels, and Molecular Chemistry Section at RTF. Vehicle owners, who
with their cars, became collectively the important feature of this "real-world"
experimental study arc each acknowledged for their generosity of involvement.
The cooperation of many individuals from organizations with participating fleet
vehicles was also instrumental in carrying out the study.
xn
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SECTION 1
INTRODUCTION
BACKGROUND
In 1974 and 1975 several engine stand ?nd prototype vehicle studies'1'8)
demonstrated the potential of catalyst equipped cars to emit suIfuric acid
fsulfate) aerosol at sufficient levels to be of identifiable concern. As the
tnpnufacturing commitments to oxidaiive catalyst emission control technology
were made well in advance of these findings, the need for a sulfate emissions
data base from assembly-line produced, consumer-driven and consumer-maintained
vehicles was evident. Sulfate emissions drta for this puipose were part of a
more comprehensive investigation of in-use catalyst cars summarized in this
project report, \fliile this work was in progress much of the concern for
vehicular sulfate emissions lessened, mostly in response to the low emission
rates found, especially from non-air pump cataiyst cars(9-12). In the
present study, a group of vehicles were repeatedly tested over a period of
two and a half years to characterize suifate emissions, HC/CO/NOX emissions
under different test modes, idle HC/CO levels, fuel economy in laboratory
and over-the-road (OTR) driving, catalyst activity, purge of stored sulfur
from catalysts, particulate emissions, state of engine tune, and tank fuel
characteristics.
The collection of field-service vehicular data is usually more time-
consuming, cumbersome and expensive than permitted or warranted by the demands
of -time and the many questions for which data are needed. However, emission
and fuel economy characteristics of consumer-driven and maintained vehicles
relate directly to air pollution and energy consumption in general, and pro-
jections for the vehicle popul .ion at large are not always accurate if based
on results from prototype vehicles. Within limitations, this project's data
base should be useful for a variety of emission and fuel economy evaluations
for first generation catalyst cars.
VEHICLE TESTING METHODOLOGY
A vehicle test protocol WPS adopted in response to specific data elements
considered essential to the study. Vehicles were tested in "as-received"
condition upon delivery to the New York State Department of Environmental
Conservation Automotive Emissions Laboratory (AEL). Numerous engine param-
eters and idle HC/CO exhaust levels were logged, and a tank fuel sample was
collected in preparation for dynrmomstcr testing. HC/CO/NOX emissions were
measured by the 1975 federal Test Procedure (FTP)(13) applicable to these cars.
-------
A one hour 50 mph steady cruise test was included to: 1) collect particulate
for 10 elemental analyses by x-ray fluorescence (XRF)i 2) pre-condition the
vehicle's catalyst for subsequent sulfate measurements during the Congested
Freeway Driving Schedule (CFDS)(14); and 3) provide a comparison'of sulfate
emissions between 50 mph cruise and the CFDS. Five successive CFDS test
cycles were adopted to insure stabilized sulfate emission rates, since sulfur
storage/release from catalysts had been identified as causing observations of
erratic values of tailpipe sulfate emissions for successive test cycles (2,15-17).
At the last vehicle test catalyst activity for HC and CO conversion was
measured by sampling raw exhaust before and after the catalyst at idle, 30 mph
and 50 mph.
Fuel economy was measured in all dynamometer test modes by carbon balance
procedure. In addition, each vehicle was equipped with an engine hour meter
and totalizing fuel meter throughout the project to provide over-the-road
average speed and fuel economy between tests. Necr the end of the project, a
Highway Fuel Economy Test (HFET) was added to further characterize dynamometer
fuel economy.
Test protocol and laboratory analyses procedures are covered in Section 8
in further detail.
VEHICLE TEST GROUP
Fifty-six 1975/76 model year catalyst-equipped cars made up the test
group sample. Table 1 is a roster of these vehicles listing vehicle informa-
tion and a "car number" identifier used throughout this report. Figure 1 is
a mileage test point roster. While a total of 266 tests were performed, 10
tests were deleted as technically defective; therefore, 256 vehicle tests
serve as the data base for this report.
Car #1 was stationed at AEL as a control vehicle and served as an over-
night loan car in order to gain access to other test-group vehicles. It was
fueled exclusively at AEL and maintained in accordance with manufacturer's
specifications. The remainder of the test group vehicles were drawn from
four institutional fleets in the Albany, N.Y. area and private vehicles
accessed by letter solicitation to owners of all 1975/76 cars in the New York
State Department of Environmental Conservation parking lot, 50 Wolf Road,
Albany, N.Y. No screening criteria were used in establishing the test group.
Private vehicle owners were provided a fill-up of gasoline and two car wash
tickets as the only 'incentive for participation. Vehicle test and check-in
results were provided to these owners only upon their request to minimize the
influence of the testing program oh these vehicles.
Table 2 provides a breakdown for 256 vehicle tests by vehicle manufacture,
model year and ownership.
'.
The test group is not statistically representative of the vehicle popula-
tion at large. No particular attempt was made to accurately represent all
makes, engine family types, inertia weight classes, etc. However, the test
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Table 1
TFST GROUP ROSTF.R
Make
Model
Trana Carp Vent.
Faml ly
Air Cond
10
11
12
11
14
IS
It
17
IS
19
20
21
22
2)
Ik
25
26
27
28
29
30
11
)2
I)
3'.
31
to
37
38
3»
40
it
42
4)
64
45
4h
47
48
49
50
it
52
5)
V.
55
56
.
1975
1 ClJt
i»/O
1975
1'7}
1
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Figure
MILEAGE TEST POINT ROSTER
-DENOTES EMISSION TEST ON VEHICLE
to
21
oo
o-»
Z5
2t>
Z7
29
29
3O
32
33
^c
Vi
«7
4 '
*\4
*
*
*
.
1
.
*
*.
r M
.
* -~
.
r
t ₯
1
5
0 5 10 15 20 25 30 35 40 45 50 55 60 65
MILEAGE IN THOUSANDS
4
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group encountered "refl-world" factors in nuch the same manner as the general
vehicle population. This hypothesis is supported by the similarity of idle
CO patterns in the test group to those from P larger sample of catalyst cars
throughout New York Stfte. tested ?s prrt of s 25,000 car, 5-year idle
emissions inventory '11, 18).
TABLE 2. CLASSIFICATION OF CARS AND TESTS
56 Cars
29 Fleet Cars
26 Personal Cars
1 Control Car
1975 Model Cars
1976 Model Cars
1977 Model Cars
256 Emissions Tests
143 Fleet Tests
102 Private Tests
I
t
11 Control Tests
General Motors
21
6
14
1
8
11
2
95
29
55
11
Ford
10
2
8
0
4
6
0
38
7
ji
0
Chr.-sler
24
20
4
0
17
6
1 i
1
1
120
104
16
0
AMC
1
1
0
0
0
1
0
3
3
0
0
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SECTION 2
CONCLUSIONS
SULFATE EMISSIONS
For 256 vehicle tests, CFDS sulfate emissions averaged 3.1 rag/mi, and
only 147. of these tests gave sulfate emissions in excess of 10 mg/mi. These
emission rates are significantly less than prototype results (I, 15, 16, 17)
and are attributed to oxygen starvation of non-air pump catalyst systems with
maladjusted carburetors. Another factor influencing these results was the
low sultur content of commercial unleaded gasoline used Cor testing (project
average 0.020 wt % S).
FTP CARBON MONOXIDE EMISSIONS
CO was the most common pollutant outside the design standard for these
vehicles, being greatly affected by maladjusted carburetors. Only 93 of 256
tests gave FTP CO at or below the 15 gin/mi standard. Idle CO level corre-
sponded to FTP CO emissions. For the 116 tests characterized by idle CO less
than 1% FTP CO emissions averaged 12.9 gin/mi, in contrast to the 140 tests on
vehicles with idle CO greater than 1% which averaged 42.5 gtn/rai FTP CO.
FUEL ECONOMY
Laboratory carbon balance fuel economy measurements showed close corre-
spondence to EPA certification values applicable to test group vehicles. Fuel
economy based on 1.5 million miles of over-the-road driving averaged about
10% higher than the measured FTP (city) values. Over-the-road vehicle speed
pveraged 33 mi/hr in contrast to 21 mi/hr for the FTP.
PURGE OF S02 FROM CATALYSTS
Catalysts stored sulfur in some operational modes, and released S0£ upon
deceleration to idle. This phenomenon was pronounced for vehicles with
carburetors characterized by idle CO > 1%. /
CATALYST CONVERSION ACTIVITY
Exhaust sampling before/after catalysts near the conclusion of the
project showed 70% of the vehicles (30 out of 43) to be capable of 90% CO
-------
ppd 75" HC conversions. Therefore, most LesLs in this project are considered
to 'i.-»v»' iH-fii performed on vehicles with active cptalysts.
Hvon active catalysts showed large- decreases in CO conversion at idle
if the crrburetor was adjusted to give high engine-out CO 0 17,). This
phenomenon results in dormant catalysts at times of high emissions, and also
accounts Cor the observed decrease in CO emissions for cars restored to
proper carburetor adjustmc-nt.
EMISSION TRENTJS WITH MILEAGE ACdWULATION
Emission rates of the measured pollutrnts were not found to be a
consistent function of vehicle mileage.
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SECTION 3
REGULATED AND SULFATE EMISSIONS
INTRODUCTION
No single method for organizing the data from these in-use vehicles has
been -found to be completely satisfactory. Instead, several different
a roaches have been included in this report in order to provide a composite
picture of how various emissions related factors interrelate. In this
section the data base has been analy7td by the following: 1) individual
vehicle emissions averages; 2) mileage accumulation trends of the overall
fleet; 3) individual vehicle mileage accumulation trends; and 4) tests grouped
by various parameter subclassifications.
EMISSION RESULTS AVERAGED BY CAR
i
Emissions of each car, averaged over all tests on that car, are shown by
car number in Table 3. The number of tests per vehicle and the mileage
interval spanned from the first to last test are indicated for each vehicle.
HC/CO/NOX results are reported for the FTP. CFDS, and 50 mph cruise tests.
CFDS values in Tnble 3 are taken from the second CFDS cycle, as discussed in
Section 5.
EMISSION TRENDS WITH MILEAGE ACCUMUTATION: OVERALL TEST GROUP
Changes" in emissions with mileage accumulation for the test group were
investigated by averaging all tp«=ts in the data base in 5,000 mile intervals
(i.e. 0-5k, 5-10k miles, etc.). These results are shown in Table 4.
Individual columns in Table 4 show average emission rates for successive
5,000 mile intervals. Idle CO averaged 1.3% in the first interval, rose to
2.47. in the 5k to 10k mile interval and was relatively unchanged thereafter.
The increase in FTP CO in the second 5,000 mile interval parallels the in-
crease in idle CO. FTP HC emissions show an overall increasing trend with
mileage accumulation. N'0X levels showed no significant change with mileage.
Particulate sulfate emissions in both the 50 mph cruise and the CFDS show a
significant falloff with increasing mileage.
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3. Avriagc tnlnslnn Ki'Bulll by Car
CAR MMC'i
i rrsii TEWrt
1 11 2'.'J76.(i
2 I, 3i-.'«.7.7
1 7 41nb<>.l
4 '. 3 1 6 3 1 . 6
1 4 l.t.9.7
6 1 JJJI9.4
1 5, J14b4.9
e 5 11)114. 9
9 i i727e.5
10 5 10509. *'
11 5 17666.3
1? 0 36715.1
13 1C 14719.')
14 2 7H2B. 1
IS 4 28799.9
16 j 37876.2
17 S 36202.9
IB 5 12412.6
19 37367.]
20 404A4.9
21 V9012.6
22 11961.1
2} 2943B.2
24 1286.4
35 28704.0
26 ::i7i.O
27 26067.9
2B 19104.7
29 21752. J
30 1794-1.)
31 1P091.4
32 37030.7
33 26S60.4
34 24631.7
Jl 11)861.1
36 31692.2
37 10944.2
38 30299.9
39 14162. J
40 4222.8
41 2)181.9
42 27107.7
4J 29JJ6.8
44 13B09.7
45 12J84.1
46 2713S.4
47 26144.9
48 2J5V0.5
49 6I«.0
jO . 6084.0
11 J3771.6
52 15487.9
51 76846.7
54 31842.9
11 " 17011.6
56 4V19D.6
IMF
CO *
O.dl
l.-ir
J.7J
4.16
1 .80
O.U4
2.74
1. 14
3. .4
1.08
2.00
0.04
5.39
0.70
3.95
1.57
0.00
3.18
1.90
1.46
5.06
2.00
5.17
1.75
0.00
0.28
3.10
2.92
1.98
0.30
0.38
5.32
0.97
5.24
0.66
1.90
4.B7
0.07
0.63
4.45
2. 65
2.98
1.98
0.03
2.40
7.18
1.55
4.28
3.80
0.60
U.OO
1.23
0.4U
0.08
3.b3
2.37
FTP MJ-I CFDS
HOT
HC CO CO(l) NT* HC CO TJOX Sfto -.MID HC CO HOZ SC4 SC4I?)
U. II >1.28 1.36 l.'lj U.O,' li.UI I.JI1 ').7', 14.44 U.Of 1.10 1.-4 9.CI 14. ',0
l.JM Ji.80 2li.'.l J."7 II.IM '..l; .'.n O.JO O.J7 0.1" 13.75 2.«0 0.22 0.4|
2. .7 56.79 4..-.V3 J.t.1 0.01 (..ii7 ..7'J j.31 4.39 I'.il 15.71 J.16 1.3V 2.bb
1.16 66.06 47.71 1.J3 a.i.t |.l; .01 1 . ?4 2.04 J.H. 17.02 1.72 1.20 2.14
i.i't 41.45 .(J.07 2-iH U.l.u '..'.I .-it I..J4 0.56 U.67 /. Id 2.19 U.."j 0.41
11.16 7.68 4.13 2.-J1 u. Ill U.,/4 .1.1 1.U2 2.31 U.ll 1.52 3.2P 0.72 1.7?
2.47 30.14 20.74 3.1" O.U9 O.UO .1J >-.|9 6.17 0.93 6.42 2 95 0.29 0.'J4
O.U9 5.82 11.71 1.12 0.13 O.U9 .""I 1U.34 22.23 0.13 0.46 2.51 8.04 21.00
2.17 4:. 54 1C." 2.J7 0.13 U 05 .71 1.54 9.72 0.47 4.50 2.15 1.28 4.81
1.24 21.02 '.->< 2.22 0.06 U..., .91 4.60 5.33 0.15 1.12 1.75 O.U5 0.93
1.52 25.56 9.1J 3.J2 0.06 0.00 .32 4.42 5.04 0.19 2.16 1.00 1.01 1.31
2.49 29.78 B.73 1.80 U.22 0.17 .71 6.15 7.86 0.38 1.60 2.09 9.78 14.12
1.74 75.00 51.41 3.12 0.03 O.t'4 .67 1.98 3.66 0.64 17.39 4.45 0.15 1.02
0.93 39.13 31.60 1.10 0.11 12.38 .63 3.07 6.04 0.23 16.65 1.09 0.67 1.45
2.01 56.38 24.84 2.71 O.C8 0.03 .42 1.43 12.20 0.16 7.88 1.90 1.1!) 2.41
1.69 44.10 11.49 1.79 0.11 0.03 .76 4.20 7.14 0.17 2.90 2.09 4.97 9.81
1.71 8.22 4.33 2.17 0.21 0.24 .16 1.26 6.P2 0.32 2.00 2.79 3.84 4.97
1.40 28.36 11.18 1.68 0.10 0.01 .11 1U.48 13.31 0.30 4.76 1.S6 1.7h s.BIl
2.09 46.75 17.61 2.33 0.11 0.10 .72 13. 5fl 18 80 0.16 4.18 2.38 6.S2 10.79
1.55 26.58 8.20 2.96 D.Ob 0.07 .56 4.29 5.1V 0.27 2.78 2.J3 2.52 3.02
2.72 49.22 30.70 2.16 0.12 U.U9 .45 2.17 2.66 0.63 9.06 1.26 0.11 0.71
1.17 20.28 16.34 1.89 0.05 .1.40 .1H U.ll 0.27 0.25 6.21 .'.26 0.07 O.It
2.32 41.02 28.40 2.91 0.07 0.00 .54 3.91 6.03 0.16 9.47 2.37 0.36 0.54
1.25 24.90 24.27 2.03 0.13 2.77 .34 9. OR 13.98 0.40 8.95 2.31 2.34 4.22
0.87 3.41 2.33 2.91 0.14 0.17 .14 7.19 8.11 0.27 0.7S 1.72 8.P6 10.23
1.17 13.91 10.35 3.84 0.72 4.17 .J3 6.76 8.85 0.92 4.91 1.51 7.0J 9.73
4.23 52.2? 44.34 2. '2 U.ll 7.46 .19 0.4U 0.74 1.41 24.40 2.56 0.42 0.67
1.44 20.92 16. b9 2.6i 0.04 U.UU .}'. 0.44 0.61 0.36 4.78 2.11 0.37 0.61
1.34 15.18 11.87 2.40 0.04 (1.00 .13 0.16 0.70 0.30 4.05 2.61 0.11 0.71
0.71 6.55 2.82 6.06 0.1)6 0.01 .49 0.17 0.87 0.15 1.7J 5.73 0.11 O.M
1.28 28.80 21.21 2.64 0.115 1.24 .11 2.78 2.98 0.42 14.51 1.16 0.82 0.87
2.42 34.76 25.61 2.65 0.05 0.00 .08 0.18 0.44 0.",2 v.10 2.83 0.58 1.62
1.64 26.21 20.48 2.61 0.11 l.HO .92 1.11 0.97 U.68 12.07 2.00 0.5) O.M
2.14 67.60 6J.H7 2.49 0.04 O.UJ .11 11.57 16.91 0.61 21.56 1.13 0.54 O.bl
1.51 11.72 C..08 2.46 0.04 0.02 .34 17.25 20.99 0.21 2.42 2.96 1.79 5.91
1.10 17.02 1.77 3.40 0.09 0.04 .48 6.31 9.54 0.19 1.44 2.65 0.97 1.45
1.27 29.11 22.04 1.91 O.Q4 fl.Ol .12 0.46 0.61 0.18 10.17 1.73 0.57 0.74
0.74 6.68 1.67 1.34 0.09 0.01 .57 2.48 1.74 0.17 0.97 1.19 1.41 2.26
1.01 9.81 7.71 1.86 0.07 1.02 .18 0.55 1.19 0.17 1.47 1.64 0.69 1.10
2.20 34.80 10.31 7.09 C.06 0.01 .27 1.49 1.20 0.61 8.00 2.23 0.44 0.19
O.C9 20.08 11.09 4.7* 0.19 3.00 .IS 0.20 0.42 0.35 9.05 1.94 0.68 1.34
1.U1 36.68 24.75 .'.23 n. 10 0.01 .21 1.38 11.11 0.41 8.40 2.71 1.30 2.PO
1.64 j4.91 11.04 2*81 0.11 O.in .19 2.77 4.41 0.17 5.25 2.01 0.50 0.84
0.49 2.21 0.51 4.71 0.12 0.01 .74 18.49 18.16 0.19 0.40 5.08 16.25 16.11
1.18 28.71 23. Ill 2.17 0.31 !.?7 .16 4.19 5.92 0.46 7.61 2.44 3.10 4.14
1.50 "18. 98 15.11 1.61 0.24 0.78 .11 7.17 10.68 0.52 7.00 1.8] 8.18 12.22
1.41 14.41 9.96 1.70 0.69 1.11 .49 4.44 6.49 O.U9 1.45 1.55 1.66 6.81
1.17 27.45 21. lit 2.91- O.UJ 0. 1U .76 0.11 0.97 C . 24 6.00 1.68 0.14 0.18
1.00 21.11 20.12 1.72 0.08 O.OU .03 1.72 8.87 0.57 7.4] 3.84 0.91 1.17
1.21 12.30 1.18 2.12 U.07 0.03 .06 1.U1 8.44 0.21 2.10 2.21 Lit 1.66
0.18 H.04 4.8V 2.11 O.Ub 0.01 .32 2.1} 1.22 0.18 4.10 2.20 0.9* 1.67
0.8A 2.9) 0.12 1.04 0.11 0.02 .1) 30.17 54.12 0.21 0.10 2.03 33.18 61.57
1.17 11.46 6.96 2.77 O.UJ 0.01 .'11 5.41 7.21 0.24 1.01 1.60 1.87 1 67
u.85 11.01 7.92 l.HO O.OH 0.47 .211 U.41 0.76 0.20 5.1) 2.28 0.45 0.82
5. OB 110.91 97.34 1 . -Ji 1.77 41.77 .98 0.16 0.97 2.77 61.01 2.44 0.64 1.11
1.17 11.77 47.12 1.16 4.50 211.12 .09 11.99 12.81 2.30 16.70 2.86 11.79 10.90
H*«n- 4.6 27117.0 2.16 1.72 2b.»0 19.JO 2.6) 0.2S 2.25
NOTK. HC. CO. NOX all (|a/nl). S04 (ng/crt)
(I) Hot FTP CO with Big 111 for Bag I
(2) S04 v«lue> (djuitid to 0.010 ut. X fuel (uUur
2.24
1.14 7.77 0.14 8.2i 2.73 1.20 5.29
-------
Table 4
AVERAGE RESULTS BY MILEAGE INTERVALS
MILEAGE
INTERVAL
0-5
5MO
10-13
IS -2O
20-29
25-30
30-35
35-40
40-45
45-5O
>50
«ft
TESTS
27
29
37
28
37
25
26
13
16
7
9
IDLE
C0(%)
1.3
2.4
2.2
2.3
2.9
2.2
1.5
'2.3
2.0
2.0
2.5
FTP
HC CO NOx
.0 17.5 2.6
.4 25.8 2.6
.6 27.5 2.6
.8 29.7 2.5
.6 31.2 2.5
.7 31.6 2.7
.9 29.2 2.7
.9 31.3 32
2.3 329 2.9
3.3 46.8 2.4
2.4 38.0 2.9
50 mph CRUISE
HC CO NOx S04
O.I 06 2.3 11.8
0.1 0.4 2.1 6.7
C.2 1.4 2.2 7.3
0.1 2.5 20 7.2
0.2 1.7 2.1 5.7
0.2 2.2 2.5 8.1
0.3 2.2 2.4 8.3
O.I O.I 2.7 4.9
0.2 1.0 2.6 52
«.7 10.7 2.8 6.5
0.1 O.I 2.7 4.5
CFDS
HC CO NOx S04
0.2 3.8 2.7 100
O.4 7.6 2.6 7.7
0.7 7.1 2.7 3.7
0.5 9.5 2.5 4.5
0.9 7.8 2.6 2.7
0.5 9.2 2.9 6.8
0.5 6.9 2.9 4.1
0.5 7.2 3.3 1.8
0.8 8.9 3.3 3.0
1.3 19.1 3.0 6.7
0.5 7.2 3.2 2.4
NOTE: MILEAGE INTERVALS IN THOUSANDS OF MILES
HC, CO, N0», ALL (grit/mi)
S04 MEASUREMENTS NORMALIZED TO 0.030 WT.% FUEL SULFUR, IN (mg/mi)
-------
EMISSION TRENDS WITH MILEAGE ACCUMULATION: INDIVIDUAL VEHICLES
Loast-squares-regressions of emissions results for tests on individual
vehicles have been used to compute mileage accumulation trends. The compu-
tation?! procedure is simil?r to that used to determine "deterioration
fr-ctors" ?s defined in federal certification procedures (10). In new car
certification, the change of an emissions parameter with accumulated mileage
is computed as the ratio of the emissions at 50,000 miles to emis.sions at
4,000 miles, as determined by the straight line regression of test data. This
definition of deterioration could not be applied here since all cars did not
accumulate the same number of miles, and the emission data sets frequently
exhibited sufficient scatter so es to preclude extrapolation to a common
50,000 :nile basis as required by the "deterioration factor" definition.
A common 10,000 mile basis for comparison of emissions trends among test
group cars was adopted to avoid extrapolation difficulties. For each vehicle,
a straight line regression was used to compute a change in emissions for this
common 10,000 mile basis. Dividing this emission change per 10,000 miles by
the mean of the emission data set used for the regression yields a normalized
"percent change in 10,000 miles". These values are not a comparison of the
absolute emission rates among the test group vehicles, and only indicate how
an individual vehicle's emissions changed as a percentage of its own average.
The "percent change in 10,000 miles" values for the 56 test group cars thus
serve as a basis for additional comparisons; histograms of these values for
the test group give a picture of the variability in trends with accumulated
miles for various emission parameters and test cycles.
Hydrocarbon Trends ,
Figure 2 contains histograms of the mileage accumulation trends in HC
emissions for the test group for FTP. CFDS and 50 mph cruise. The "percent
change in 10,000 mile" abscissa ranges from -100% to +1007., the ordinate,
"test group cars", is expressed as a percentage of the vehicle sample. In a
few instances the least squares regression lines resulted in trends in excess
of + 100% change in 10,000 mites, and these have been arbitrarily excluded in
the preparation of histograms (the number of vehicles used being noted on
each histogram). The mean HC trend for the FTP is a 14% increase in emissions
per 10,000 miles. CFDS and 50 mph cruise are similar to the FTP, although
the absolute emissions levels in these test modes are lower (Table 4).
Carbon Monoxide Trends V
Figure 3 shows mileage accumulation trend results for CO emissions in
the same format as Figure 2. Idle CO trends are also presented in this figure.
For each test mode in Figure 3 the mean change is only a few percent, con-
sistent wit'. ..he relatively unchanged emissions in the 5,000 mile intervals
of Table 4.
The range of "percent change in 10,000 miles" of FTP CO appears to bo
less than either the CFDS or 50 mph cruise. This must be viewed in light of
11
-------
Tig 2 MILEAGE ACCUMULATION TRENDS FOR HC EMISSION'S
JC
28
24
§
u
§16
6
I"
8
4
rt
nil
N=54
-
4O 80
28
24
20
16
12
8
4'
n
Men
pp
i nrrrf
i
52
i=16.4
ft
?£
28-
24
20
16
12
8
4'
n
nnf
M^nt(B7
II
"
n
-80 -4O
4O 80
-80 -40
% Change m 10,000 Mi
FTP
% Change m C.OOOMi
CFOS
% Change in 10,OOOMi
SOmph Cruise
12
-------
Fig. 3 MILEAGE ACCUMULATION TRENDS FOR CO EMISSIONS
C.O
24-
g20-
2
o
ex
6 12-
Tn
8
4-
0
28
24-
§20-
e
o
o 16-
~ 12-
M
8-
4-
n
I
n
N = 52
Mean= 4 7
.
i r
-80 ' -40 ' 0 40 8O
% Change in 10,000 Mi
FTP
"
IF
N=43
"
~
Mean= -34
_ _
e.o
24-
g20
a is-
^12-
8-
4-
28
24-
g20-
C
O
I16
»12.
^i
8-
4-
n
Ifflff
N=50
Meon=-14
"i ^n
-
-80 -40 0 ' 40 80
% Chgnge in 10,000 Mi
CFDS
n r
^l
N = 49
'Mean = 53
!
-
-i i-j
nn
-80 -40 o *0 80
% Change m iO.OOOMi
SOmph Cruise
-160 -80 o 80
% Change in lO.OOOMi
IDLE
13
-------
the absolute CO mass emissions in each segment, FTP, CFDS and 50 mph cruise
averaging 29.1, 7.8, 1.6 g/rni respectively. Small changes in emissions from
test to test for an individual vehicle often have a greater relative effect
on the CFDS and 50 mph cruise. In Figure 4 "percent change in 10,000 miles"
values for idle CO and FTP CO are plotted against each other. Car number
identifiers ?re indicated beside each point. The results of test data
presented graphically in Figure 4 are summarized in Table 5. Trends in idle
CO and FTP CO values correspond except for values for 6 vehicles with increas-
ing idle CO and decreasing FTP CO. Four of these six vehicles are Fords
(air pump vehicles).
Two institutional flsets began to use HC/CO analyzers to maintain their
vehicles near the conclusion of this study. This change was unknown to us at
the time, but corresponds to observations of decreasing idle CO values
observed for several high mileage vehicles. T.-»n of the 21 vehicles with
decreasing idle CO values were from these two fleets.
NOy Trends
Figure 5 shows histograms of NOX trends for the FTP, CFDS end 50 mph
cruise test modes. The range of mileage accumulation trend values for NOX
are less than for HC and CO, and are also more consistent among test modes.
Particulate Sulfate t
Figure 6 shows the effect of mileage accumulation on particulate sulfate
emission rates for the CFDS and 50 mph cruise, with emission rates normalized
to a common 0.030 wt % sulfur fuel. The substantial percentage changes are
again in part a reflection of sensitivity due to low emission rates.
EMISSIONS RESULTS CATEGORI7ED BY INDIVIDUAL TESTS
Above, the data for each test group car were treated as an independent,
mileage-related data set. Analysis of test results for mileage accumulation
trends from individual cars implicitly assumes a relationship among the test
data for any given car. The fact that tests were all performed on the same
vehicle does not totally define this relationship for the test data since
events between test points Xparticularly vehicle maintenance) can abruptly
influence emissions. The range of positive and negative trends in the above
histograms, especially idle CO, demonstrates this point. The predominant
such event observed in this study was a major change in idle CO between tests.
<
As an alternative to treating the data on each car as a mileage dependent
data set, each test was considered as being independent of other tests. In
Table 6 the results of all tests have been tabulated for various subclassi-
ficstions without regard to the cars on which they were performed. The number
of tests and cars in each classification is indicated. Tables 7, 8, and 9 are
similar to Table 6 with only the cars of the indicated manufacturer included.
Sulfate results in Tables 6, 7, 8, and 9 are as measured, and not normalized
to 0.030 wt 7, for sulfur fuel.
14
-------
Fig. 4 Comparison of Idle CO and FTP CO Trends
100-
50-
o
o
o
o"
"
2
o
-50-
-100-
-150-
50 51
ts
V ««. .»
»6
r.s32-«'
1» II
19
40
|»
IT
.. V4
2 Tests
-350 -300 -250 -200 -150 -100 -50 0 50 100 150 200
% Change in 10,000 Mi
IDLE
15
-------
Table 5
CO Trends by Mileage Accumulation
Comparison of Idle CO and FTP CO
56 CARS
IDLE
C0(%)
increasing t
decreasing |
unchanged -
FTP C0(gm/mi)
increasing t
19
4
4
decreasing 1
6
19
2
unchanged -
2
0
0
16
-------
Fig 5 MILEAGE ACCUMULATION TRENDS FOR NO, EMISSIONS
-------
Fig. 6 MILEAGE ACCUMULATION TRENDS FOR SULFATE EMISSIONS
o
o
It
12-
ID-
S'
6-
4-
2
o
N= 51
Mean= 0.2
r
MB
-
-
-
-i
11
-80 -40
80
% Change in 10,000 Mi
Particulate Sulfate, SOmph Cruise, .03Owt %
Fuel Sulfur
it
12-
10-
o
o
& 6-
o
I4'
2-
o
N = 47
Mean =0.1
-80 -40
40 80
% Change in 10,000 Mi
Particulate Sulfate, CFDS, .030 wt %
Fuel Sulfur
18
-------
TABLE 6
Average Emission Results
All Tests, All Manufacturers
vO
Classification _. No.
of Tests . - Tests
All
FTP CO < 15 gm/rai
FTP CO < 15 em/mi. HC < 1.5 ^m/mi
FTP CO < 15 gm/mi, HC < 1.5 gm/mi
NOv < 3. 1 gm/mi
Idle CO ^ 1%
Idle CO » 1%
FTP CO * 45 gm/mi
Stall in Beg I of FTP
Fleet Vehicles
Private Vehicles
0 - 15,000 miles
15,000 - 30,000 miles
30,000 - 45,000 miles
AS. OOP miles
256
93
87
66
116
140
51
58
143
102
93
90
57
16
No.
Cars
56
31
28
26
39
47
18
31
29
26
45
51
37
13
Idle
COX
2.2
0.4
0.4
0.5
0.2
3.8
4.9
1.8
2.4
2.1
2.0
2.5
1.9
2.3
FTP
gm/mi
HC
1.7
0.9
0.8
0.8
1.0
2.3
3.4
1.5
1.9
1.6
1.4
1.8
2.0
2.8
CO
29.1
8.0
7.8
8.0
12.9
42.5
70.3
24.6
35.1
22.6
24.1
30.9
30.8
41.9
N0,:
2.7
2.8
2.8
2.3
2.7
2.6
2.6
2.4
2.5
2.9
2.6
2.6
2.9
2.7
1 Hr
HC
0.2
0.1
0.1
0.1
0.1
0.3
0.5
0.1
0.2
0.2
0.2
0.2
0.2
0.3
50 m.ph
gm/mi
CO
1.6
0.2
0.1
0.1
0.6
2.5
5.0
0.9
1.3
2.3
0.9
2.1
1.4
4.7
Cruise
NOx
2.3
2.4
2.4
1.9
2.3
2.2
2.7
2.1
2.2
2.5
2.2
2.2
2.6
2.6
mg/mi
504
5.0
7.3
7.9
7.8
6.9
3.5
4.7
7.8
5.1
4.5
6.1
4.5
4.3
4.5
HC
0.5
0.2
0.2
0.2
0.2
0.8
1.2
0.4
0.5
0.5
0.5
0.5
0.6
0.9
CFDS
gm/mi
CO
7.8
1.8
1.7
1.9
2.4
12.3
21.4
6.5
8.3
7.9
6.3
8.7
7.6
12.4
NOX
2.8
3.0
2.9
2.5
2.9
2.7
3.1
2.6
2.7
3.0
2.7
2.6
3.1
3.1
mg/mi
S04
t
3.1
i
6.0
6,1
6.4
5.5
1.2
0.7
5.2
2.3
I
3.5 !
4.0
2.7
2.3
3.0
-------
TABLE 7
Average Emission Results
General Motors Vehicle Tests
Classification
of Tests
All Oncr.il Motors Vehicles
FTP CO < 15 gm/mi
FTP CO < 15 gm/mi, HC < 1.5
FTP CO < 15 gm/mi, HC < 1.5
N'Ox < 3.1 gm/mi
Idle CO < 17.
Idle CO ^ 17.
FTP CO > 45 gm/mi
CFDS S04 > 10 mg/mi
Fleet Vehicles
Private Vehicles
0 - 15,000 miles
15.000 - 30.000 miles
30.000 - 45.000 miles
45,000 miles
No.
Tests
95
46
gm/mi 45
gm/mi ,
36
53 '
42
7
6
29
55
" '33
40
19
3
No.
Cars
21
13
13
12
15
14
3
2
6
14
16
19
11
3
Idle
C07.
1.6
0.2
0.2
0.2
0.1
3.6
3.8
0.0
0.7
2.4
1.6
2.1
0.9
1.3
HC
1.4
0.8
0.7
0.7
0.9
2.1
4.3
0.7
1.1
1.8
1.1
1.7
1.2
2.7
FTP
gm/mi
CO
21.8
8.2
8.1
8.4
9.9
36.8
84.3
9.2
14.5
27.8
18.8
26.0
17.7
25.8
NOX
2.7
2.8
2.8
2.3
2.7
2.7
2.6
1.9
2.4
3.0
2.4
2.7
3.2
2.2
1 Hr
HC
0.1
0.1
0.0
0.0
0.1
0.2
0.9
0
0.1
0.2
0.1
0.2
0.1
0.2
50 mph Cruise
gm/mi
CO
2.4
0.1
0.1
0.1
0.3
5.1
20.7
0
1.3
3.5
1.5
3.6
1.2
4.0
NOx
2.2
2.2
2.2
1.7
2.2
2.3
2.3
1.4
1.9
2.6
1.9
2.3
2.8
2.4
mg/mi
S04
2.3
3.3
3.3
3.8
3.8
0.5
0.4
13.4
1.6
1.2
2.4
1.8
2.9
5.8
HC
0.4
0.2
0.1
0.1
0.2
0.7
1.9
0.1
0.3
0.6
0.3
0.5
0.4
0.8
CFDS
gn/mi
CO
8.1
2.3
2.3
2.5
2.8
14.8
44.5
1.0
5.8
10.7
6.5
10.2
6.0
9.9
NOX
2.7
2.8
2.8
2.4
2.8
2.6
2.6
2.1
2.7
2.9
2.4
2.8
3.2
2.7
mg/mi
S0£
1.8
2.8
2.9
3.4
3.0
0.4
0.4
14.9
1.1
0.7
1.8
1.6
2.1
4.4
-------
TABLE 8
Average Emission Results
Ford Vehicle Tests
Classification
of Tests
All Ford Vehicles
FTP CO < 15 em/mi
FTP CO < 15 sm/mi, HC < 1.5 gin/mi
FT? CO < 15 gm/mi, HC < 1.5 gm/mi,
KOX < 3.1 gm/mi
Idle CO < IT.
Idle CO >> 17.
FTP CO - 45 gm/ml
CFDS S04 » 10 mg/mi
Fleet Vehicles
Private Vehicles
0 - 15.000 miles
15,000 - 30,000 miles
30.000 - 45,000 miles
45,000 miles
No.
Tests
38
.24
:
21
12
23
15
0
12
7
31
18
15
5
0
No.
Cars
10
7
7
5
P
6
0
6
2
8
8
9
5
0
Idle
C07,
1.3
0.8
0.9
1.4
0.2
3.0
.
0.8
1.2
1.3
0.9
1.8
1.2
HC
1.1
0.9
0.8
0.8
0.9
1.4
.
0.8
0.9
1.2
1.0
1.2
1.4
FTP
gm/mi
CO
13.6
5.4
4.5
3.4
8.7
21.1
'
3.9
15.4
13.2
8.3
18.7
17.6
1 Hr
50 mph Cruise
gin/mi
NOX
2.8
3.1
3.1
2.2
3.1
2.3
.
3.2
2.3
2.9
3.4
2.2
2.1
HC
0.3
0.3
0.2
0.2
0.3
0.3
.
0.2
O.I
0.3
0.3
0.2
0.3
CO
1.8
0.5
0.2
0.1
1.9
1.5
.
0.3
3.6
1.3
1.3
1.9
3.1
NOX
2.5
3.0
3.0
2.1
3.0
1.8
.
2.9
1.5
2.7
3.0
2.1
2.0
mg/mi
S04
9.6
13.0
13.8
16.1
12.2
5.7
.
18.0
8.3
9.9
11.2
8.9
6.0
CFDS
gm/mi
HC
0.5
0.4
0.3
0.3
0.4
0.6
.
0.3
0.3
0.5
0.4
0.4
0.6
CO
4.2
1.1
0.8
0.5
2.7
6.4
.
0.6
5.1
4.0
2.2
6.2
5.4
NOX
2.9
3.3
3.3
2.5
3.2
2.4
.
3.4
2.1
3.1
3.5
2.5
2.3
mg/mi
S04
9.3
13.5
14.2
16.5
12.8
3.9
.
20.8
6.0
10.0
11.5
7.7
5.8
,
-------
TABU 9
Average Emission Kesuics
Chrysler Vehicle Tests
Classification
of Tests
All Chrysler Vehicles
FTP CO < 15 gm/mi
FTP CO < 15 Rm/ml. HC < l.S cm/mi.
FTP CO < 15 gm/mi, HC < 1.5 gra/mi,
NOX < 3.1 gm/mi
Idle CO < 17.
.Idle CO ^> 1%
FTP CO > AS gtn/ni
CFDS S04 > 10 mg/mi
Fleet Vehicles
Private Vehicles
Police Cruisers
Fleet -- No Police Cars,
Fleet and Private Vehicles --
No Police Cars
0 - 15,000 miles
15,000 - 30,000 miles
30,000 - 45.000 miles
45,000 -liles
No.
Tests
120
22
20
17
38
82
44
19
104
16
28
76
92
40
34
33
13
No
Cars
24
10
8
8
15
24
14
11
20
4
4
16
20
20
22
22
10
Idle
C07.
2.9
0.6
0.6
0.6
0.3
4.1
5.1
1.9
3.0
2.5
3.2
2.9
2.8
2.9
3.4
2.5
2.5
FTP
gm/mi
HC
2.2
1.0
0.9
0.9
1.2
2.6
3.2
1.4
2.3
1.6
2.6
2.1
2.0
1.7
2.1
2.6
2.S
CO
39.8
10.5
10.5
10.2
19.3
49.3
68.1
30.3
42.2
22.9
50.8
39.3
36.4
35.9
41.5
40.4
45.5
NOX
2.6
2.5
2.4
2.2
2.6
2.6
2.6
2.4
2.5
3.0
2.8
2.4
2.5
2.4
2.6
2.8
2.8
I Hr
50 mph Cruise
gm/mi
HC
0.2
0.1
0.1
0.1
0.1
0.3
0.5
0.1
0.3
0.1
0.5
0.2
0.3
0.1
0.1
0.2
1.0
CO
1.0
0.0
0.0
0.0
0.0
1.4
2.5
0.0
l.l
0.0
3.1
0.4
0.2
O.I
0.3
1.2
4.9
NOx
2.3
2.3
2.2
2.1
2.2
2.3
2.7
2.4
2.3
1.9
3.2
2.0
2.0
2.1
2.1
2.5
2.7
mg/mi
S04
5.8
9.8
10.3
11.1
8.3
4.6
5.3
18.5
5.9
5.1
4.6
6.4
6.2
7.0
5.9
4.9
4.2
CFDS
gm/mi
HC
0.6
0.2
0.2
0.2
0.2
0.8
1.1
0.3
0.6
0.5
0.8
0.6
0.6
0.6
0.5
1.0
0.9
CO
8.7
1.4
1.3
1.3
1.3
12.1
17.7
5.9
9.1
5.9
14.9
7.0
6.8
7.7
8.0
8.9
13.0
NOX
2.8
2.8
2.7
2.5
2.8
2.8
3.2
2.7
2.6
2.7
3.7
2.5
2.5
2.5
2.6
3,2
3.2
mg/mi
SO*
2.2
*.7
5.1
5.9 ,
4.8 >
i
i.o !
0.8
6.9
2.4
0.9
2.3
2.4
2.2
2.7
1.8
1.9
2.6
-------
Tables 6, 7, 8, and 9 were used to evaluate the cars and tests against
various emission criteria. Applicable emission standards for these vehicles
ere 1.5/15/3.1 (gm/rai) for HC/CO/NOX respectively. Table 10 is extracted
from Tables 6-9 and indicates the number of cars and tests meeting various
combination v-of these emission standards. The idle CO < 17. criteria shows
a general correspondence to the FTP CO < 15 gin/mi criteria.
Toblt 1O
TESTS GROUPED BY EMISSION CUT POINTS
ALL TESTS
FTP:CO< 15
FTP-CO<15,HC<1.5
FTP-CO 1%
CFDS S04>10mg/mi
ALL
TESTS
37
19
GM
FORD
Chrysler
22
NOTE- 3 tests on 4 AMC vehicle not included
HC.CO. NO, oil (gm/mi)
23
-------
SECTION 4
FUEL ECONOMY
LABORATORY AND OVER-THE-ROAD DATA
Laboratory fuel economy was measured by the carbon balance technique for
FTP, CFDS and 50 mph cruise segments of each vehicle test. HFET fuel economy
was added in the final few months of testing. Average over-the-road (OTR)
fuel economy and vehicle speed were obtained between vehicle test points by
use of fuel and hour meters installed on each car at the beginning of che
project. Further experimental details are presented in Section 8 of this
report.
Table 11 lists the average fuel economy results obtained for each of the
test group cars throughout the two year.' of testing. The HFET was included
as a part of the test sequence at test #118 in August 1972; by that time 12
vehicles had left the project. Except for three vehicles with more than one
test after this date, HFET and Combined fuel economy reported are for the
final test on each vehicle. Table 11 also gives EPA fr.el economy results for
certification vehicles corresponding to test group vehicles by e.igine family
and inertia weight specification(20-22). Figure 7 shows speed versus time
traces for the three EPA driving schedules used in this study; Table 12 gives
some characteristics of the various laboratory test cycles.
TABLE 12. TEST MODE CHARACTERISTICS
FTP
HFET
Combined
CFDS
50 Cruise
length
(miles)
11.1
10.2
10.7
13.5
50.0
average speed max speed
(mph) (mph)
21.3
48.2
28.4
34.8
50.0
56.7
59.9
59.9
57.0
50.0
time stops/mile
(sec.)
1877
765
1135
1398
3600
2.1
0.1
0.2
0.2
0.0
time at idle
(W
19.2
1.0
2.1
2.3
0.0
Average fuel econotiy from carbon balance and OTR measurements are shown
graphically in Figurt S as a function of average vehicle speed for the various
test segments. The C.~R data covers 1.5 million vehicle miles and averaged
32.8 mph and 15.1 mpc.
24
-------
TABLE 11
AVERAGE FUEL ECONOMY FUCK TEST CRCXT VEHICLES
AEL Carbon Balance KPC Hc»«ur«neni»
At.L Over Tnt Ro«d Meat jreaent i
FPA UPC
Car «
1
2
3
6
5
6
7
B
9
10
11
12
13
16
1}
U
1?
IB
19
20
21
22
23
24
25
26
27
28
29
30
?l
31
33
31
35
56
37
3e
39
60
41
42
43
6i
45
66
47
48
49
SO
51
52
S3
54
55
56
Means
STD. DEV
FT?
9.9
12.1
9.1
10.3
16.9
11.9
16.6
13.6
11.3
16.9
16.9
10.2
9.4
8.5
10.6
10.7
11.2
10.9
11.0
16.7
16.1
IS 3
16 0
9.S
19.3
11.6
14.2
16.7
17.9
U.I
12.0
20.2
15.0
9.6
10.1
18.0
IS. 9
1S.S
11. S
12.6
1°.B
11.9
17.6
16.9
10.7
18.0
12.1
23.6
17.3
10.2
12.4
16.6
9.7
13.3
11.6
8.1
13.7
3.S
H"tT
1S.S
..
..
17.6
2S.9
..
28.1
16.0
22.2
2S.1
23.8
13.4
..
..
17.8
17.6
-.
16.7
IS. 8
2S.2
23.1
-.
22.8
..
29 2
17.4
23.4
23.6
33. 5
-.
IS. 9
3S.O
21.5
16.9
16.6
23.6
..
21.3
..
..
27.9
19.7
2S.6
20.5
16. S
27.0
19.7
36.3
2S.O
16.2
17.3
1<».5
17.8
18.1
17.3
13.2
21.4
S.S
CoiMne>!
12.1
..
..
13.4
20.0
..
22.3
17.2
13.8
21.0
19.0
11.3
..
13.6
13.4
..
13.2
12.4
19.6
18.3
--
18.3
..
22.7
13.9
19.9
19.6
23.3
..
13.6
26.3
17.5
12.5
12.6
20.3
..
17.5
..
.-
22.3
14.7
20.9
17.7
13.1
21.2
IS. 2
27.6
20.
11.
16.
16.
13.
13.
13.?
10.0
17.0
6.2
CFD5
13.3
15.8
13.0
16.0
23.0
16.0
22.6
16.8
16.7
22.8
23.2
13.3
13.6
11.7
16.6
16.6
IS. 2
16 4
14 7
22.8
22.2
20.5
21.6
13.2
25.8
15.3
19 7
21.9
26.3
21.1
15.6
28.1
18.5
13.8
14.1
22.7
20.6
19.9
15.7
16.6
26.6
16.5
22.9
19.9
16.7
26.3
16.6
31.7
22.6
13.7
16.3
17.8
13.6
16.8
15.2
11.6
16.3
6.6
50 Cruise
15.6
17.9
16.9
18.6
25.4
18.0
25.9
18.3
18.6
26.3
26.3
17.1
15.6
13.0
18.6
16 6
17.5
18 3
17.7
26.3
26.1
26 1
25.6
16.9
31.7
18.1
23.9
26.7
36 1
26.3
17.6
34.3
21.6
17.7
17.9
25.6
23.1
22.8
17.7
19 3
30.0
20.8
25.9
21.6
17.3
26.1
19.9
36.9
25.9
15. S
19.0
20.3
16.2
19.9
17.7
13.8
21.5
5.6
FTP HFET COB* i-
30.5
30.5
27.6
33.0
26 8
35.1
33.6
36.2
38.6
SO. 6
36.2
39.2
37.0
37.6
28.2
33.6
31.6
37.3
38.7
38.6
3. .3
:s.o
36.2
37.1
36 1
27.5
28.5
21.6
60. 3
36.1
19 2
35.2
40.2
36.8
36.9
36.6
26.6
36.1
36.2
23.9
35. 2
26.8
31.1 '
22.6
33.0
32.5
35.7
25.7
19.6
26.1
31.9
27.6
36.3
32.2
26 8
65.4
32.8
6.0
10.6
11 7
7.1
11.9
16.3
13.2
16.9
11.6
13.1
21.7
18.2
1!.3
6.2
6.3
13. S
12.4
11.0
13.2
13.7
17 8
16.6
15.2
16.6
12.6
23.8
12.2
16.1
16.9
25. 8
26 5
9.7
23.7
19.2
12.8
12.5
17.6
16.7
17.6
13.6
10.7
20.3
13.1
21.8
15.7
15.6
20.6
16.6
22.8
..
..
13.5
16.6
8.7
13.1
12.0
..
1S.1
6.6
10
16
10
12
17
16
17
16
12
17
17
12
10
10
12
12
16
12
12
18
18
17
17
10
26
13
IS
18
22
IS
13
19
17
13
13
18
16
16
IS
13
19
13
16
16
11
22
13
30
18
12
16
16
11
16
13
9
1S.O
3.9
16
18
IS
17
23
18
23
18
17
23
23
17
IS
16
17
17
16
. 17
17
23
23
25
23
16
36
19
23
23
35
19
16
78
23
17
17
23
21
23
21
18
28
17
23
21
16
31
19
39
23
16
19
21
15
19
18
17
20.6
5.2
11
IS
12
16
19
IS
19
16
16
19
19
16
12
11
16
16
IS
16
16
20
20
20
19
11
27
15
16
20
26
17
15
22
19
16
16
20
16
19
17
IS
22
15
20
ie
13
26
IS
33
20
13
16
16
13
16
16
11
17.0
4.3
25
-------
TRANSIENT
PHASE
BAGSI83
too
80
= 60
i«o
20
O
20
STABILIZED
PHASE
BAG 2
200 400 600 600
TiME, sec
FTP (or LA-4.UODS)
10 oo
1200
1J7I
100
80
.1 *°
20
0
6O
40
200 40O 600 800
TIME, sec
CFDS(orSET-7,(CUE)
IOOO
<200
use
765
Figure 7
FTP.CFDS AND HFET DRIVING SCHEDULE
(SPEED vt TIME)
26
-------
Vehicle test group averages are presented for measured carbon balance
FTP, HFET, CFDS and 50 mph cruise fuel economy at the bottom of Table 11.
The EPA certification FTP fuel economy value of 15.0 mpg was in very close
agreement to the measured OTR value of 15.1 mpg. Measured FTP fuel economy
averaged 9% less than the OTR economy while the HFET and 50 mph cruise values
overestimated the actual OTR economy by 41 and 427. respectively. Figures 9, 10
and 11 show the same results as Figure 7 for three engine family groups:
Chrysler 225 CID 1-6 cylinder, Chrysler 318 CID V-8, and Buick 350 CID V-8,
respectively. Laboratory fuel economy results within these engine family
groupings are quite uniform as seen by the + Lr bounds indicated.
Fuel Economy Trends With Mileage Accumulation
Plots of fuel economy vs. mileage accumulation were prepared for each test
group vehicle. From these, data trends of fuel economy with increasing vehicle
age can be evaluated. Figures 12, 13 and 14 are typical of the variety of
fuel economy results obtained on three test group vehicles.
For most vehicles the fuel economy is relatively unchanged with mileage.
Some long-term drift, both increasing and decreasing fuel economy, is observed
as in Figures 12 and 13. Large jumps in fuel economy between two test points,
such as in Figure 14, are not uncommon however. It has proved impossible to
systematically determine the reasons for such changes in every case. Change
in vehicle driver, rapid deterioration of drive-train, major and minor main-
tenance, etc., are not part of the data base, making correlation of fuel
economy with all pertinent vehicle parameters impossible. Increases i'n fuel
economy have been noted for several (but not all) vehicles when idle CO level
dropped significantly.
Fuel economy and mileage accumulation data were fitted with straight
lines from which slopes, normalized to a 10,000 mile basis, were computed in
the same manner as for emissions trend analysis as in Section 3. The slopes
from all vehicles were then used to prepare histograms showing percentage
change in ftfel economy per 10,000 miles for the test group. Figure 15 contains
the histograms for the FTP, CFDS and 50 mph cruise. In all three cases, an
increase of approximately 27. tuel economy per 10,000 miles was found.
Analysis of OTR Fuel Economy Results
The average fuel economy and vehicle speed data between laboratory test
points has been analyzed for seasonal variation and effect of vehicle inertia
weight. Fuel economy from all intervals was first averaged for each car, and
the ratio of fuel economy in each interval to the overall average for that
vehicle computed. Data from all cars and all intervals were then plotted
against the month in the year, computed as the midpoint between test dates.
Figure 16 shows these fuel economy results, and Figure 17 shows average vehicle
speed plotted in the same manner. From these figures, no seasonal shifts in
vehicle economy or speed are ap'parent. Seasonal changes may be obscured by the
method of using the calendar midpoint to represent the interval between tests.
The range of fuel economy and speed variations shown in Figures 16 and 17 give
an indication of the OTR variability for these parameters. Average vehicle
27
-------
IS}
OB
E
27
26
25
24
23
21
20
18
17
16
13
14
13
11
10
20
FTP
FUEL
Figure 8
ECONOMY BY TEST MODE
mpg vs. mph
56 Vehicles, 256 Emissions Testa,
1,530,873.7 Over The Road Miles
i
t> AEL Carbon Balance mpg
1 (±10~ Bounds Identified)
6 EPA Carbon Balance mpg
* Average Over The Road mpg 8 mph
Measurements For 1,530,873.7 Miles
25
30
COMB.
35
CFDS
mph
40
45
50
HFET
CRUISE
-------
NJ
vO
a
E
31
30
29
28
27
26
25
£4
23
22
22
21
20-
19
18
17
16-j
15
20 )
FTP
Figure 9
225-16 CHRYSLER
FUEL ECONOMY BY TEST MODE
mpg vs. mph
10 Vehicles, 35 Emissions Tests,
213,667 Over The Road Miles
A EL Carbon Balance mpg
(1
-------
w
o
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
20
. Figure 10
318- V8 CHRYSLER
FUEL ECONOMY BY TEST MODE
mpg vs. mph
8 Vehicles, 35 Emissions Tests,
264,229 Over The Road Miles
£
AEL Carbon Balance mpg
(tier Bounds Identified)
EPA Carbon Balance mpg
Average Over The Road mpg & mph
Measurements For 264,229 Miles
FTP
25 | 30
COMB.
45
CFDS
mph
HFET
50
T
50
CRUISE
-------
22
21
20
19
18
17
16
o15
a
6 14
13
12
10
9
8
7
6
5
Figure 11
350-V8 BUICK
FUEL ECONOMY BY TEST MODE
mpg vs. mph
5 Vehicles, 25 Emissions Tests,
167,509 Over The Road Miles
AEL Carbon Balance mpg
(tlor Bounds Identified)
EPA Carbon Balance mpg
Average Over The Road mpg ft mph
Measurements For 167,509 Miles
20
25
30
FTP
COMB.
35
Cf^DS
mph
40
45
1
5?
HFET 5*0
CRUISE
-------
FUEL ECONOMY vs MILEAGE ACCUMULATION
Figure 12 CAR NO. 2
20-1
:
10
f
-FTP
Ftood
20
0 5 10 15 20 25 30 35 4O 45 50
Figure 13 CAR NO. 19
s \
115J
1
10
Road
FTP
36
"5
1
0 5 10 15 20 25 30 35 4O 45 50
Figure 14. CAR NO. 25
50 Cruise
16
0 5 10 15 20 25 30 35 40 45 50
ODOMETER (thousands)
32
-------
Figure 15
MILEAGE ACCUMULATION TRENDS FOR
CARBON BALANCE FUEL ECONOMY
TOTAL VEHICLE SAMPLE GROUP
CJ
20
Q
UJ
V>
£15
OT
UJ
U
fe
^o 5
. .
J
1
Li
£
MEAN INCREASE" 2 OZ%
(Par 10 ,000 Miles)
-
in
i r
W
1_
y
-------
2.0
1.9
i.e
1.7
1.6
1.5
1.4
I.I
1.2
1.1
1.0
0.9
0.8
0.7
0.6
O.S
0.4
0.3
0.2
0.1
0.0
M = (interval DTK rapg)/(Average Car OTR mpg)
*
* *
* +
Figure 16. Seasonal OTR Fuel Economy*
-------
w -
m 5
2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1.1
1.0
0.4
0.8
0.7
0.6
O.S
0.4
0.3
0.2
0.1
0.0
S - (Interval OTR mph)/(Average Car OTR wph)
J J A
Month
. Figure 17. Seasonal OTR Vehicle Speed
-------
speed from all intervals is also shown in Figure 18 as a cumulative frequency
plot.
Several analyses were performed to establish a relationship between
vehicle inertia weight and Tuel economy. While inertia weight had a signifi-
cant effect on fuel economy in comparisons among individual cars, the wide
range of results at any one inertia setting and the limited weight range
representation in the test group did not support any conclusions quantifying
a general relationship between fuel economy and vehicle inertia weight.
Control Vehicle Fuel Economy
OTR fuel economy and vehicle speed are available for the project control
vehicle (# 1) for every tank fill in the course of the scudy, spanning over
30,000 miles. The control vehicle was fueled exclusively from a 1,000 gallon
tank at AEL using commercial lead free fuel. These data are for much snorter
time and distance intervals than the 5,000 mile test interval values used for
the calculation of other test vehicle OTR fuel economy. Figure; 19 and 20
show OTR fuel economy and average speed for this vehicle for each tank fill
by month of the year.
In Figure 19 a gradual seasonal fuel economy shift is noticeable during
the warmer months. Each point in Figure 19 represents at most a few hundred
miles and a time period of not more than a week. This allows the data to be
more sensitive to factors such as type of usage, weather and road conditions,
etc., than for the OTR intervals on other test group cars where eac.h interval
represents about 5,000 miles and several months.
36
-------
100
S 90-
LJ
vi BOi
ui 70
V 60-
^ 30-
40*
g 20
58 10
Figure 18
CUMULATIVE FREQUENCY DISTRIBUTION
OTR VEHICLE SPEED
56 Vehicles, 178 Intervals,~2 5 Million Miles
10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46
SPEED (mph)
L
-------
u>
17
16
IS
14
1)
12
11
10
9
8
7
6
5
4
3
2
1
'0
**
**
* +
* *
AHJJASON
Month
Figure 19. Seasonal OTR Fuel Economy for Control Vehicle.
mini iMnlffrr ""-
-------
70
60
mph
\o
40
30
20
» «
'. .v .
*
AHJJASON
Month
Figure 20* Seasonal OTR Vehicle Speed for Control Vehicle.
-------
SECTION 5
CHARACTERI7ATION OF PARTICULATE EMISSIONS
INTRODUCTION
Particulate samples were analyzed for sulfate content as one of the key
objectives of the project, and these emission retes have been presented in
Section 3. Addition?! analyses provide a more complete characterization of
the parliculate emissions for these cars and are included in this section.
SULFATE EMISSIONS
Stabilized CFDS Sulfate Emissions
Previous studies (1-8) of sulfate production from catalyst-equipped
vehicles have shown that the efficiency of conversion of fuel sulfur to
sulfate particulnte is dependent on catalyst type (monolith or beaded) and the
presence or absence of an air pump. Measurement of sulfate particulate
emissions from catalyst-equipped cars is complicated by storage and release of
sulfur-bearing compounds from the catalyst. Early studies of prototype cars
(2, 15, 16, 17) frequently showed large variations in observed emission rates
from the same vehicle in series of back-to-back tests. Therefore, five con-
secutive CFDS cycles were used in order to insure representative CFDS sulfate
values.
After 155 tests, analysis of the five CFDS cycles yielded fairly consis-
tent patterns of sulfate emissions for three of the four possible catalyst/air
pump configurations. The five CFDS sulfate emission rates were individually
averaged over all tests representing each configuration to ascertain a com-
posite pattern of sulfate emissions variation for the given system configura-
tion. These results .are shown in. Figures 21, 22, and 23 for the following
configurations: 1) monolith without air pump, 73 tests; 2) monolith with air
pump, 22 tests; and 3) beaded without air pump, 51 tests. Since only 9 tests
on two vehicles comprised the last configuration, beaded with air pump, this
group was not analyzed for emission variations.
Examination of cycle'T sulfate averages for the monolith without air pump
configuration reveals cycle 1 sulfate emission rates which are significantly
higher than the average of cycles 3. 4, and 5. Indeed, almost half of the
tests on vehicles with this configuration exhibit cycle 1 emissions which are
greater then the above pverage value by more than three times the standard
40
-------
SULFATE EMISSIONS FOR CFDS CYCLES
Figure 21. MONOLITH CATALYST WITHOUT AIR PUMP
30
2.0
=! 1.0
to
STD DEVIATION
*~ BOUNDS
REPRESENTATIVE
AVERAGE
234
CYCLE NO.
|150-
CO
V)
je
Ul
2 5.0
n
STD. DEVIATION
BOUNDS
REPRESENTATIVE
AVERAGE
o
<
K
LJ
1.5
1.0
05*
12345
CYCLE NO.
Figure 23. BEADED CATALYST WITHOUT AIR PUMP
STD DEVIATION
- BOUNDS,
REPRESENTATIVE
AVERAGE
234
CYCLE NO.
41
-------
deviation. As seen in Figures 22 and 23, there appears to be little "memory"
of previous test cycles for the monolith with air pump and beaded without air
pump configurations, -for all three configurations, the second CFDS cycle
gives an average sulfate value within the standard deviation bounds defined
by the lest three CFDS cycles. Therefore, in order to simplify test protocol
while still maintaining data integrity, only two CFDS cycles were run for
tests #163 and beyond. On this basis, all individual vehicle sulfate emission
rates presented in Section 3 are the second CFDS value. Detailed analysis of
sulfate emission rates in Sections 5 and 7 use the second CFDS value fur tests
after #162; for tests where 5 CFDS cycles exist the average of the last 3
cycles were employed.
Sulfate Emissions at Idle
Two filters were collected during idle periods of the test sequence for
tests up to and including test #162. One was collected during the 5-minute
idle separating the 50 mph cruise from the first CFDS cycle, the other was a
composite sample from idle periods after CFDS cycles 3, 4, and 5. BCA analy-
sis of these filters showed low levels of sulfate emissions during idle
operation. When a driving cycle and its associated idle period were combined,
less than 27, of the sulfate collected and 0.2% of the fuel culfur recovery
could be attributed to the idle period.
Sulfate Emission Rates
Sulfate emissions as percent of fuel sulfur recovery are presented in
Table 13. All emission rates have been normalized to 0.030 wt 7. S using
actual fuel sulfur values provided by fuel analysis. Fuel sulfur content, as
well as fuel lead and manganese, are indicated in Figure 24 as three month
running averages.
TOTAL PARTICULATE MASS
.Total particulate mass was determined for every filter collected. Par-
ticulate from the cold-start FTP usually appeared as a black carbon-like
deposit, while the CFDS and 50 mph cruise tests showed a tan or white partic-
ulate. Sulfete emissions from the FTP were lower than for the CFDS or 50 mph
cruise. Table 14 gives totnl particulate mass, averaged over all tests on
each car, for the FTP, CFDS, and 50 mph cruise segments. The percentage of
this particulate found to be sulfate is indicated for each segment. Also
presented in this table are comparisons of relative emission rates of total
particulate in CFDS and 50 mph cruise relative to FTP results.
ELEMENTAL PARTICULATE ANALYSIS BY XRF
Perticulate samples from the 1-hour 50 mph cruise were analyzed for 10
elements by x-ray fluorescence (XRF). Elements analyzed were: bromine, lead,
zinc, copper, iron, sulfur, calcium, phosphorous, aluminum, and manganese.
The 1-hour cruise was adopted in order to collect sufficient particulate for
42
-------
Table 13
Sulfate Emissions as % of Fuel
Sulfur Recovery By
Catalyst/Air Pump Configuration
Configuration
Tests Fuel Sulfur Recovery as Sulfate(%)
Sulfate Emission Rate (mg/mi)
Monolith '.Jithout Air Pump
Monolith with Air Pump
Beaded without Air Pump
Beaded with Air Pump
All Tests
124
39
80
16
259
FIT
0.82
2.33
0.50
0.60
0.94
50 Cruise
6
14
1
6
6
.31
.26
.58
.32
.04
CFDS
1.98
14.13
0.94
6.00
3.74
HFET
2.79
36.33
2.14
15.74
7.24
FIT
1.72
4.29
0.89
1.34
1.83
50 Cruise
8.08
17.20
2.03
10.16
7.71
cros
3.21
18.70
1.32
10.13
5.39
3
31
?
25
10
IIKET
.53 (24)
.33 (8)
.75 (11)
.49 (5)
.30 (44)
Note: All sulfate emission rates normalized to 0.030 weight percent
sulfur in fuel.
For HFET # of tests are indicated in parentheses.
-------
Figure 24
FUEL ANALYSES
THREE MONTH RUNNING AVERAGES
NUMBER OF SAMPLES USED IN AVERAGES (229 TOTAL)
8 . B , 6 . 9 t 12 , 15 , 18 , 14 t 7 , 11 , 10, T , 7 , 5 . 1 , 6 , 16, 9 t 9 , 14 g I ,0,9,9.9,9,2
.020
.010
1
i
.000
.020
MANGANESE ANALYSIS BEGAN DEC. 1976
o
.000
.040-
D20-
0
1975
JFMAMJJASONO
1976
LL
JFMAMJJASONCI F
19V7 1978
-------
Table 14
Total Articulate Dritsicns ty car
Total Paniculate ng/n TP; % of FTP
« T> at S04
CARt t
1
2
3
4
5
6
7
t
9
10
11
12
13
14
IS
16
17
16
19
20
21
22
23
24
25
2fc
27
26
29
30
31
32
33
34
35
36
37
36
39
<0
41
42
43
44
45
46
47
48
45
SO
51
52
53
1<
55
56
AVLFACb
of Tests
11
6
7
5
4
4
5
S
5
5
S
S
10
2
4
3
5
S
4
5
S
4
6
2
6
4
5
5
4
4
4
S
3
S
S
5
3
6
3
2
4
4
4
3
4
5
4
4
3
3
5
3
b
4
3
3
F7P
22.62
10.70
10.90
43. t6
54.28
3.76
15.11
6.34
37.65
2S.41
37.71
36.99
26.95
9.14
52.31
53.16
5.13
.6.17
34.24
26.77
44.35
4.24
31.68
10.69
11.57
41.46
32.47
3.62
11.51
4.72
11.20
10.09
12.04
22.38
17.96
13.8'.
6.92
7.55
5.78
10.98
8.07
55.35
24.36
35.49
10. 16
15.75
21.33
9.05
7.9d
6.96
4. '6
17 68
14.23
5.74
16.28
J3.97
21.70
SOC
10. (1
1.C6
S.OS
4.23
4.12
1.92
3.70
11.77
12.70
4. £4
6.25
8.25
4.40
6.46
8.47
6.18
6.10
12.54
13.52
7. 55
5.16
0.79
4.SE
9.69
11. El
13.95
7.34
1.34
1.63
1.41
10.22
O.EO
14.62
16.41
22.19
10.30
1.67
4.93
3.34
4.62
2.12
6.76
7.33
20.64
io.es
13.77
10.60
1.9B
9. 06
0.92
4.70
20.19
10.95
l.f.
11.91
18.47
U.22
CFDS
13.01
l.Et
2.2'i
4.16
4.59
2.49
4.60
14.67
5.75
2.53
3.19
I/. . 57
4.19
11.17
6.35
7.75
4.22
6. El
6.73
4.C4
4.75
1.10
2.76
3.23
13.68
23.74
9.29
1.73
3.16
2.33
9.36
3.75
7.76
4.34
6.79
5.61
5.E5
3.71
4.15
2.04
6.67
9.24
9.08
28.79
9.t5
12.26
14.97
2.<2
3.
-------
detection since emission rates were expected La be very low. Detection
limits (ug/cm? of filter area) for the :iRK system are shown in Table 15.
Translation of these detection limits to tig/mi for typical l-hour-50 mpb
cruise sampling conditions are also shown in Table 15. In addition, Table 15
lists the percentage of tests wj.ch samples below the XRF detection limit for
each element. Table 16 is a tabulation of individual car average particulate
elemental emissions. No trend with mileage accumulation was observed for
elements analyzed. Histograms in Figures 25-34 illustrate the distribution
of observed emissions. Tests with non-detectable emissions have been excluded
from these histograms and the number of exclusions indicated on each figure.
For lead, sulfur and manganese, the particulate emitted can be compared
to the fuel input for each element during the 50 mph cruise. Recoveries of
these elements based on fuel usage were low. Lead and manganese are probably
trapped in the catalyst and engine/exhaust system. Most fuel sulfur is
emitLed as SC>2 and little is found as particulate sulfur. Figures 35, 36,
and 37 are histograms of the individual test particulzte recovery percentages
for sulfur, lead, and manganese, respectively.
PARTICULATE ANALYSIS BY 7.0N CHROMATOGRAPHY (1C)
At the end of the study, ion chromatography (23) was used to analyze the
archived filters previously used for XRF analysis. Anions determined by 1C
were Cl~, Br~, PO,-, F~, and N0-j~, in water soluble extracts of particulate.
Chromatographs of these filter extracts showed low levels of the ions analyzed.
Section 8 contains a comparison of the results of the BCA, XRF and 1C analyses
for sulfui and sulfate. In Table 17 the total particulate mass emission rate
during the 50 mph cruise is broken down into a sulfete (based on XRF sulfur),
XRF non-sulfate, 1C non-sulfate and "remainder" contributions. When sulfate,
XRF non-sulfate, and 1C detected species are combined, they account for
approximately 65% of the total mass of emitted particulate regardless of the
various sub-classifications listed in Table 17. These findings are in
general agreement with results from similar work at Southwest Research
Institute (14).
46
-------
Table 15
XRF Detection Limits
ELEMENT
Lower limit of detection
by calibration standard
(microgram/cm? of exposed
filter area)
Same as above translated
to typical 1 hr. 50 raph
cruise (micrograms/mi.)
7. of tests lower than
detection limit
Br
0.05
2.2
47
Pb
0.1
4.4
27
Zn
0.2
8.8
74
Cu
0.2
8.8
91
Fe
0.05
2.2
71
S
0.025
1.1
2
Ca
0.008
0.4
33
P
0.09
4.0
24
Al
0.07
3.1
92
Mn
0.011
0.5
67
-------
Table 16* Average XKF Emissions by Car
w
Miles
Car Tests Tested Br
1 11 49176. b O.UO
2
)
M
5
5
^
8
9
10
11
12
1} 1
14
1 V
If
17
ia
19
;u
21
22
2)
24
25
26
27
28
29
10
)1
12
))
34
Ji
J6
37
18
39
40
41
42
4 J
44
45
46
47
4H
49
50
51
54
51
14
5S
bo
16467.
41869.
llbJl.
12629.
13719.
13904.
JU114.
37270.
3U509.
37606.
48771.
54719.
7B4B.
4H799.
J7b7o.
364U2.
324 12.
17367.
40464.
29U54.
IOJ',2.
29118.
J2B6.
28704.
1217S.
28067.
19504.
21752.
1794}.
I2U93.
17010.
26560.
24611.
JOBbl.
11692.
10914.
30299.
'" 14162.
4222.
414H5.
22107.
29JJ6.
11809.
322B4.
27135.
26544.
21590.
6197.
60S4.
11771.
15487.
0.12
0.04
0.01
0.21
0.01
0.00
0.01
0.01
0.02
0.01
0.00
0.08
0.01
0.01
u.oi
0.00
0.00
0.00
0.01
U.OI
0.14
0.00
0.00
0.00
0.02
0.14
0.02
0.00
0.00
0.25
0.00
O.U5
0.00
0.00
0.00
0.02
0.00
0.13
0.01
U.02
0.04
0.04
0.00
0.00
0.05
.01
.01
.00
.00
.68
.01
76H46.7 0.01
J1B42.9 P. 26
17U51.6 0.17
4V19U.b O.OB
Mean *» 327UB.il 0.07
Pb
0.01
0.01
0.01
0.01
0.02
0.01
0.02
0.11
0.04
0.01
0.02
0.01
0.01
0.10
0.04
0.01
O.U4
0.01
0.02
0.02
0.01
o.oo
0.01
o.o4
0.01
0.05
0.04
0.02
0.02
0.01
0.12
o.oi
0.08
o.oi
0.01
O.OJ
0.02
0.02
0.04
0.02
O.U2
0.04
O.U2
0.04
O.OS
0.01
0.06
O.UU
0.02
0.01
0.00
0.09
O.OJ
O.Oii
3.0J
O.IJ
0.04
Zn
0.04
0.01
0.01
0.00
o.oo
0.00
o.ui
o.oo
0.04
u.oo
o.ui
0.00
0.04
0.00
n.on
u.iiu
O.OI
U.OI
0.01
0.00
0.01
o.ou
o.ou
0.00
0.00
0.00
0.00
0.00
o.co
o.oi
O.OS
U.HO
0.01
O.UO
O.UI
o.uu
O.UO
O.UO
U.OI
0.00
U.OI
O.UI
o.ui
0.00
u.ul
0.02
u.oo
o.oi
O.UO
0.00
O.UO
0.01
o.ni
o.i-u
0.00
O.M5
0.01
Cu
0.02
0.01
0.01
0.02
n.oo
o.on
0.00
0.00
O.UO
o.ni
0.01
o.ui
u.uo
o.oo
o.oo
U.UU
U.Ul
U.UH
0.04
o.oo
o.uu
O.UO
0.00
0.00
0.01
O.UI
o.oo
o.oo
0.00
o.ou
u.oii
n.oo
o.oo
0.06
o.ui
o.oo
u.uo
U.UU
O.OI
u.oo
u.ou
0.00
o.uu
0.00
11.01
o.uu
0.00
0.00
o.uo
o.uu
o.uu
u.oo
(1.00
U.UO
u.uo
(1.00
0.01
Fe
0.01
0.01
0.01
0.02
0.00
n.oo
o.ou
0.04
n.oi
(i.OO
I). 00
0.01
O.UJ
U.OI
U.UU
U.UU
0.01
u.oo
u.oo
u.oo
0.00
0.01
0.00
0.00
0.00
0.09
11.00
O.OI
o.u.
0.00
0.02
0.00
0.05
U.Ul
0.00
U.OI
0.01
11.00
0.00
0.00
u.oi
u.oo
o.uu
0.01
0.01
u.ou
0.01
o.ou
o.ni
o.oo
0.00
0.01
(1. 04
o.ou
u . no
II. (1(1
P. 01
s
2.19
0.05
1.211
0.16
0.00
0.17
0.01
2.6H
1.67
U.96
1.18
1.41
o.co
0.16
1.4B
u.yy
1.70
4.31
3.57
1.19
0.84
U.U2
1.05
2.11
1.79
1.64
0.01
0.11
0.16
0.22
0.75
0.02
0.21
4.59
4.17
2.10
0.15
1.49
0.12
1.01
0.01
1.11
U.B6
l.frB
1.05
1.19
1.1.1
O.U4
1.7V
1.11
O.B1
5.57
1.86
0.07
0.01
1.26
1.45
Ca
0.19
0.00
0.04
0.0}
O.OS
0.02
0.04
0.05
O.OH
0.02
0.01
0.02
0.08
0.00
0.04
.0.0}
0.00
O.OS
0.07
0.04
0.04
0.02
0.01
0.00
0.03
O.OS
0.10
0.02
0.02
0.02
0.07
0.04
0.03
0.04
O.OS
O.OS
0.01
0.04
O.OI
0.00
O.OS
0.16
0.07
0.12
0.03
O.OS
0.08
0.02
0.07
0.06
0.03
0.19
O.OS
O.OS
0.13
0.13
0.06
P
0.17
0.01
0.09
0.01
O.OS
0.01
0.04
O.OS
o.in
0.02
0.04
0.02
0.18
0.02
0.04
O.OS
0.02
O.OS
0.07
0.07
0.07
0.04
0.01
0.01
0.01
0.10
0.12
0.01
0.02
0.01
0.11
0.01
O.OS
O.OS
0.07
O.OS
0.01
0.04
0.01
0.00
O.OS
0.26
0.07
0.11
0.03
0.07
0.07
0.02
0.06
0.08
0.02
0.21
0.01
0.04
0.12
O.lb
0.07
Al
0.00
n.oo
o.no
o.oo
o.oo
o.oo
o.oo
0.00
0.01
O.Ob
o.on
0.00
o.ou
0.00
0.00
0.00
0.01
o.ou
0.00
o.ou
0.00
0.00
0.00
0.00
0.00
0.01
0.00
0.00
0.01
0.00
O.OI
0.00
0.00
0.00
0.00
0.00
0.00
O.OU
0.00
0.00
0.02
0.00
0.00
0.00
o.ou
o.ou
0.00
0.00
o.ou
o.ou
u.oo
n.oo
o.ns
n.on
o.oc
n.iin
0.00
Mn
0.00
O.UO
0.00
0.00
0.00
0.00
0.00
O.or
0.11
0 >
o.oo
0.00
0.00
0.00
0.00
0.00
0.00
0.01
0.00
0.01
0.00
0.00
0.00
0.00
0.01
0.00
O.OI
0.00
0.00
0.00
0.01
o.ou
0.00
0.02
0.01
0.00
0.00
0.00
0.00
0.00
0.01
0.01
0.00
O.UO
0.00
0.01
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.00
o.no
o.no
0.00
All jjg/mi except S which is mg/mi.
-------
r
c
i
5
jS
**
0
Ul
o
u
£
w
f|
id
cr
24
20
16
12
8
4
n
Figure 25 FREQUENCY DISTRIBUTION
OF
~
PARTICULATE BROMINE EMISSIONS
134 Emission Tests in Figure
120 Tests Lower Than Detectable
Limit Not Shown
-T
n
1 HfLrrfh fTvTI n-TIr, r r^ n
O.OO OO4 OOB 012 016 O20 O24 O 28 032 O36 040 O44 O48
BROM:NE EMISSION RATE
"yi
£
.5
?
E
s
5*
>
Z
i±i
3
£5
E
UJ
>
»=
<
UJ
a:
36
32
28
20
16
12
8
4
o
n Figure 26 FREQUENCY DISTRIBUTION
OF
PARTICULATE LEAD EMISSIONS
186 Emission Tests in Figure
68 Tests Lower Than Detectable
Limit Not Shown
-
"
>|
1 rrn n n-,-, n - n r-i r-,
OOO O04 OO8 O12 O.<8 O2O O24 O 28 052 036 04O
BROMINE EMISSION RATE (mg/mO
-------
5 28
£
c
S 24
j£
6 20
s?
> <6
I 12
I.
§
Ul
Figure 27 FREQUENCY DISTRIBUTION
OF
PARTICULATE ZINC EMISSIONS
65 Emission Tests in Figure
189 Tests Lower Than Detectable
Limit Not Shown
PI rn
OOI O02 O03 OO4 OO5 O06 0.07 OO8 O.O9 OlO OH
ZINC EMISSION RATE (mg/m.)
Figure 28 FREQUENCY DISTRIBUTION
S 28
o '
*> 94.
.2
5 20
> 16
2
Ul
o 12
Ul
ct
«* 8-
Ul
a ft
wr
PARTICULATE COPPER EMISSIONS
f
23 Emission Tests in Figure
231 Tests Lower Than Detectable
Limit Not Shown
in n o
OOO 004 O08 012 O16 020 024 026
COPPER EMISSION RATE (mg/mi)
50
-------
36-r
m
I32
K 28-
ft
124
0°«
o
5 16
§
£.2
u.
UJ
> 8
S 4-
or
oL
000
Figure 29 FREQUENCY DISTRIBUTION
OF
PARTICULATE IRON EMISSIONS
74 Emission Tests in Figure
180 Tests Lower Than Detectable
Limit Not Shown
-
-
Ih nm n n n
004 008 012 016 O20 O24 028 O32 O,S6
IRON EMISSION RATE (mg/mi)
f
"s e
M
c 7
8
I 6
"5
5s 5
FREQUENCY
c>< *
o
f '
T
nL
: Figure 30 FREQUENCY DISTRIBUTION
OF
PARTICULATE SULFUR EMISSIONS
250 Emission Tests in Figure
-. ,-, 4 Tests Lower Than Detectable
Limit 'Not Shown
I
\
p
m r r r
-T ll" > rrrflfln rfl n
000 040 080
120 160 200 240 280 32O 36O 400 440 480
SULFATE EMISSION RATE (mg/mi)
51
-------
8 .6,
I ,«H
I
£ ,0
§
OC
U.
O
UJ
UJ
QL
6
Figure 31
FREQUENCY DISTRIBUTION
OF
PARTICULATE CALCIUM EMISSIONS
169 Emission Tests in Figure
B5 Tests Lower Than Detectable
Limit Not Shown
UJ
OO OO6 012 O18 O24 030 034
CALCIUM EMISSION RATE (mg/mi)
16
VI '
jt 14
.§
R 12
ti
o «>
8?
i 8
UJ
3 H
UJ
a:
u. 4
UJ
f-igure 32 FREQUENCY DISTRIBUTION
OF
PARTICULATE PHOSPHORUS EMISSIONS
192 Emission Tests in Figure
62 Tests Lower Than Detectable
Limit Not Shown
r-Tlpn
00 004 008 Ol? 016 020 024 028 O32 O36 040 044
PHOSPHORUS EMISSION RATE tmg/mii
52
-------
« 35
c
Q
1 30-
"B 25-
fc 20-
U
o 15
UJ
DC
u.
uj 10-
i
UJ
K o
1
Figure 33 FREQUENCY DISTRIBUTION
OF
PARTICULATE ALUMINUM EMISS
21 Emission Tests in Figure
233 Tests Lower Than Detectable
Limit Not Shown
-
ip n
0.0 0.04 008 0.12 0.16 0.20 024 O28 032 036 040
ALUMINUM EMISSION RATE (mg/mi)
r
5 7CH
I **
£ ^
" 40
UJ
3
u
a:
UJ
30
uj 20
< 10
Figure 34 FREQUENCY DISTRIBUTION
OF
PARTICULATE MANGANESE EMJSSIONS
84 Emission Tests in Figure
170 Tests Lower Than Detectable
'Limit Not Shown
00 001 O02 003 004 005 006 O07 O08 009
MANGANESE EMISSION RATE (mg/mi)
53
-------
32-
«
28-
24-
20-
16-
12-
I 8-
Figure 35
FREQUENCY DISTRIBUTION OF PERCENT
FUEL SULFUR RECOVERY IN PARTICULATE
4.7% Mean Recovery on 250 Tests
0
8 12
16 20 24 28
Sulfur Recovery (%)
32 36 40
Figure 36
FREQUENCY DISTRIBUTION OF PERCENT
FUEL LEAD RECOVERY IN PARTICULATE
1O % Mean Recovery on 176 Tests
Lead values below detection limit
on 68 tests not included
16 20 24 28
Lead Recovery (%)
32 36 40
54
-------
8
Figure 37
FREQUENCY DISTRIBUTION OF PERCENT
FUEL MANGANESE RECOVERY IN PARTICULATE
.a
UJ 6
12% Mean Recovery on 69 Tests
Mn values below detection limit
an 85 tests not included
I3'
2-
H
0
mi
m
u
8 12 16 20 24 28
Manganese Recovery (%)
32 36 40 44
55
-------
Table 17
Total Particulate Subclassification
Classification # of Tests
All Tests
Ford Tests
CM Tests
Chrysler Tests i
Total Particulate:
< 3 rag /mi
< 10 mg/ml
> 10 mg/mi
Tests in Mileage Interval:
0-10 k mi
10 k - 35 k mi
> 35 k mi
214
29
82 ' :
103
72
163
51
46
127
41
Total
Particulate
(mg/mi)
6.86
11.13
4.15
7.81
1.61
3.87
16.41
7.65
6.76
6.25
Sulfrte
(mg/mi)
4.44
7.99
2.10
5.31
0.67
2.19
11.62
5.92
4.15
3.68
Zxrf
non-sulfur
(mg/mi)
0.25
0.21
0.29
0.23
0\14
0.23
0.31
0.26
0.22
0.33
EIC
non-sulfur
(mg/mi)
0.14
0.08
0.19
0.12
0.11
0.15
0.13
0.17
0.14
0.10
7. of
Total Particulate
(Sulfate+xrf+IC)
64.38
69.30
58.26
67.88
57.48
62.56
70.21
73.39
62.30
60.75
-------
SECTION 6
CATALYST ACTIVITY TESTS
INTRODUCTION
Near the completion of the data collection phase of the project the test
protocol was modified to include raw exhaust measurements before and after
the catalyst through sample ports welded into the exhaust system. Data were
collected at idle, 30 mph and 50 nph cruise. Parameters measured were HC, CO
CO. concentrations, and exhaust gas temperatures.
Thirteen of the 56 cars had left the .project prior to the introduction
of catalyst activity testing, leaving 43 cars in the catalyst activity test
data base. Results of the before/after catalyst tests are summarized in
Tables 18, 19, and 20 for idle, 30 and 50 mph test modes, respectively.
RESULTS AT 30 AND 50 MPH
Conversions of HC and CO for 30 and 50 mph tests were used to identify
those cars vith active catalysts. Using an arbitrary criteria of 75% HC and
90% CO conversion, 707. of th'e 43 cars tested were active at the last test in
the project. A breakdown by catalyst system configuration gave the following
percentage of active catalysts in each group: 1) monolith without air pump,
73%; 2) monolith with air punp, 88%; and 3) beaded without air punp, 54%.
Since this activity test was performed as the last test for each car, we con-
clude that the la-rge majority of tests during the study were performed on
cars with active catalysts.
RESULTS AT IDLE
Many of the catalyses identified as active for CO oxidation at 30 and
50 inph were inactive at idle. For example, Table 21 shows a comparison of
results for two cars, similar in their 30 and 50 mph activities, but exhibit-
ing markedly different idle CO conversions. For car 23, engine-out idle CO
of 1200 ppm is 100% converted, whereas for car 21 no conversion was found with
an engine-out idle CO of 15,000 ppm (1.5%). When engine-out CO is high the
intrinsic capacity of the catalyst to oxidize CO is overcome by the CO levels
present in the gas rcream. This phenomena was not apparent for HC conversions
at idle.
57
-------
Table 18 Catalyst Activity Measurements at Steady Statet Idle
Ui
00
Car Number
1
6
s
7
8
9
10
11
12
IS
16
18
19
20
21
23
25
26
27
28
29
31
32
34
35
30
38
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
Catalyse
Inlet Conccntratlons(ppnO
HC
1700
. 2300
600
1400
9000
tSOO
2800
1200
1400
2000
900
2100
3800
2800 .
9100
1600
1500
6500
1800
10000
6600
7000
7800
3800
1700
1600
s:oo
4100
2000
7000
1300
900
3100
1800
3500
4000
3300
5500
5500
3600
8700
6800
9800
CO
1200
15800
700
4100
35600
9000
15800
14800
5300
24400
2700
15000
13600
11200
15000
1200
1400
1700
10500
61200
62000
1400
73500
47000
8000
7600
1300
16JCO
12500
1700
3800
6500
26000
7700
47000
4500
4400
900
14000
2200
2200
26500
35200
Average Converter
Tegycrature( C)
347
296
244
196
216
214
136
218
375
25C
2? 5
238
417
234
274
295
287
396
260
235
162
360
171
252
303
160
211
144
304
146
298
437
350
378
366
136
314
290
288
431
294
260
356
Catalytic ConversienQJ
HC
81
22
15
22
13
23
4
0
72
23 .
13
33
84
44
86
83
62
89
23
7
34
95
40
27
33
19
43
26
70
11
86
67
20
81
27
23
53
76
15
79
85
24
0
CO
100
0
0
0
15
89
0
2
99
3
0
0
99
17
0
100
100
82
0
1
0
100
23
0
8
0
24
0
85
4
100
65
15
100
0
2
35
88
8
96
100
12
16
Mass Cenversion(g/mln)
HC
0.45
0.15
0.01
0.04
0.25
0.32
0.00
0.00
0.38
0.12
0.03
0.17
1.30
0.24
1.30
0.28
0.14
1.52
0.09
0.09
0.21
1.69
0.27
0.29
0.17
0.07
0.46
0.10
0.29
0.09
0.30
0.24
0.08
0.37
0.12
0.09
0.54
0.82
0.13
0.57
1.22 ;
0.28
0.00
CO
0.80
0.00
0.00
0.00
2.21
5.03
0.00
0.09
3.96
C.32
0.00
0.00
11.27
0.73
0.00
0.51
0.42
0.74
0.00
0.19
0.00
0.71
2.89
0.00
0.40
0.00
0.12
0.00
4.51
0.02
2.05
3.56
1.14
1.39
0.00
0.02
0.96
0.31
0.35
0.85
0.74
1.08
3.23
Exhaust
How Rate SCm
20.2
18.6
9.2
8.3
12.7
19.1
5.0
9.0
22.9
15.8
14.2
14.7
25.0
12.0
10.2
12.8
9.0
16.2
13.7
7.7
5.7
15.5
5.3
17.3
18.5
0.7
11.7
5.8
12.9
7.4
16.3
25.6
8.8
15.6
7.7
6.6
18.7
1-2.0
9.7
12.0
10.2
10.6
17.4
-------
Table 19 Catalyst Activity Measurements at Steady State: 30 qph
in
NO
Car Hunter
1
4
5
7
8
9
10
11
12
IS
16
16
19
20
71
23
25
26
27
28
29
31
32
34
35
36
38
41
42
43
44
4}
46
47
48
49
50
it
52
53
54
Si
56
Catalyst
Inlet Concentrations(ppin)
Average Converter
Temperature( C)
Catalytic Converston(I)
HC
500
1200
1200
1000
2300
1400
1200
1100
1400
1300
1500
1400
1'.00
2000
9100
1400
1700
700
1300
2400
1400
1400
1700
2500
1700
1400
1500
1300
2200
1600
600
500
3100
500
2500
13CO
1800
1300
1600
1000
1100
5300
10000
CO
1800
1900
1100
700
9200
8000
1300
900
1300
6500
800
1300
900
2C.OO
800
500
19HOO
3800
3600
6000
1700
400
900
15500
500
900
800
900
6500
900
400
... 4200
19800
1800
6800
800
4200
600
3600
1400
1300
50000
11900
425
366
360
330
375
386
352
364
380
370
343
374
392
360
382
357
462
502
465
325
360
442
310
326
362
324
302
354
378
340
422
506
424
458
425
330
450
428
428
464
370
394
554
HC
87
16
90
86
43
82
92
84
88
86
85
91
93
92
98
91
82
76
24
29
90
95
59
19
93
80
76
90
92
82
86
67
16
82
62
89
41
91
86
71
88
23
27
CO
100
15
100
100
34
100
100
100
100
99
100
100
100
100
100
100
96
100
0
0
100
100
61
0
100
96
87
100
100
97
100
72
21
100
36
100
54
100
100
99
93
12
44
Mass Conversiendt/mllc)
HC
0.28
0.09
0.34
0.25
0.36
0.41
0.38
0.34
0.62
0.56
0.57
0.56
0.76
0.77
2.98
0.48
0.50
0.30
0.11
0.23
0.32
0.63
0.17
0.20
0.81
0.37
0.46
0.35
0.81
0.49
0.28
0.23
0.15
0.26
0.28
0.41
0.41
0.70
0.70
0.21
0.36
0.54
1.78
CO
2.36
0.28
0.70
0.44
2.33
5.82
0.90
0.67
1.33
6.54
0.72
1.15
1.06
2.19
0.54
0.38
14.21
4.41
0.00
0.00
0.69
0.38
0.77
0.00
0.51
0.58
0.56
0.55
5.25
0.65
0.49
1.98
2.53
2.20
0.90
0.57
2.54
0.72
3.18
0.79
0.90
5.46
7.00
Exhaust
Flow Rate SCfM
39.8
29.5
19.4
19.0
22.7
22.1
21.0
J2.7
31.0
30.8
27.3
26.7
35.7
25.6
20.4
23.1
22.0
35.?
22.1
19.9
15.9
?9.0
IliO
25:7
J1.2
20.5
24.4
18.5
24.5
22.6
37.2
40.2
18.6
37.1
11.1
21.6
34.0
36.3
26.8
17.2
22.8
26.7
40.7
-------
Table 20 Catalyst Activity Measurements at Steady States SO oph
Car Number
1
4
5
7
a
9
H-
11
12
IS
16
IS
19
20
21
23
25
26
27
28
29
31
32
34
35
36
38
41
42
43
44
45
46
47
48
49
50
SI
52
S3
54
Catalyst
Inlet Concentratlena(ppm)
HC
100
800
1800
700
600
1500
900
sno
800
500
800
1400
900
1900
8900
1300
900
900
600
700
1100
600
1200
700
1100
800
1800
1300
1500
1300
500
500
1900
1000
1600
600
600
600
800
200
600
3100
9500
CO
4600
900
4000
700
4400
1300
2:00
1100
1200
300
1500
1100
1200
1700
1100
1000
2400
1900
6000
1000
800
1500
1000
600
1200
1000
200
6600
1300
1200
800
900
800
900
2400
900
1300
1300
1600
1000
1400
23600
29300
Average Converter
Temperature(°C)
Catalytic Convorslon(Z)
641
S09
514
460
527
534
518
526
530
480
518
S38
532
493
512
498
492
S4P
518
494
454
S98
442
502
501
507
444
S18
516
490
536
566
593
509
587
473
583
SS4
536
573
541
566
628
HC
94
22
85
94
77
82
92
88
75
87
86
91
92
94
98
94
76
95
16
94
94
97
90
94
94
86
93
94
93
84
79
52
84
84
95
91
94
94
84
87
91
34
28
CO
100
39
84
100
99
98
100
100
90
100
99
100
100
ICO
100
100
96
100
0
100
100
100
100
100
100
98
100
94
100
97
99
64
98
100
99
100
100
100
99
100
100
14
46
Mass Conversion(g/mllc)
HC
0.11
0.1S
0.87
0.48
0.44
l.OS
0.63
0.35
0.74
0.43
0.70
1.21
0.94
1.03
5.78
1.03
0.51
0.96
0.06
0.60
0.49
0.68
0.51
0.61
0.81
0.45
1.36
0.67
l.OS
0.76
0.42
0.26
0.97
0.81
0.66
0.47
0.60
0.64
0.83
0.09
0.44
0.89
3.07
CO
11.23
0.65
3.84
1.02
8.61
2.17
3.42
1.63
2.56
0.56
2.67
2.11
2.73
1.97
1.47
1.69
3.62
4.40
0.00
1.74
0.76
3.54
0.96
1.55
O.S1
1.27
0.33
6.87
1.98
1.63
1.68
1.19
0.96
1.84
2.09
1.21
2.94
2.78
3.76
0.92
2.28
5.67
31.69
Exhaust
Flow Rate SCFM
70.9
55.7
34.7
44.2
60.0
51.9
47.2
44.8
72.0
56.5
58.9
58.1
69.0
35.2
40.4
51.2
47.6
70.2
41.9
52.6
29.0
71.7
29.1
58.6
31.2
39.5
49.6
33.6
46.2
42.6
64.5
63.2
37.2
62.0
26.6
40.6
68.6
64.8
71.5
29.3
49.3
51.0
71.7
-------
TABLE 21
BEFORE/AFTER CATALYST MEASUREMENT COMPARISON
CAR 2\
IDLE 30mph 50mph
CAR 23
IDLE 30mph 50mph
Engine out CO (ppm)
Average temperature (°C)
Catalyst conversion of C0(%)
Catalyst conversion of HC(%)
15,000
274
0
86
800
382
100
98
1100
512
> 100
98
1200
295
100
83
500
357
100
91
1000
498
100
94
-------
ANALYSIS OF CATALYST ACTIVITY RESULTS
Although the steady state test program emphasized a determination of
catalyst activity for each car, other catalyst behavior information was
obtained. This data has been used to provide an insight into the disparity
between idle and high speed CO oxidation, and to provide a possible explana-
tion of S02 purge behavior presented in Section 7. Idle catalyst activity
corresponds to high-speed activity for cases with low idle CO; however,
vehicles with high idle CO exhibit lower CO conversions than can be projected
from 30 and SO mph results, even though sufficient oxygen appears to be
present in the exhaust stream during idle. A conservative method was used to
project idle catalyst conversions from high speed results. Assuming a first
order rate law for CO oxidation on automotive catalysts in the low CO con-
centration regime (24, 25, 26), rate constants at measured idle gas stream
temperatures were calculated by use of the standard Arrhenius law. An acti-
vation energy of 30.0 kcal/gmole - °K was used; this vplue is consistent with
both reported kinetic data (24-29) and apparent activation energies calculated
from the present data. Using the above method and a 30 mph rate constant
calculated from the data, an -idle rate constant was projected. Idle conver-
sions of CO were then calculated from these projected rate constants. Those
tests which had measured CO conversions less than the projected conversion
were classified as being idle-inactive. Considering only active catalysts
(based on 30 and 50 mph conversions), 90% were found to be idle-inactive when
idle CO was greater than 1%, but only 217. were idle-inactive for idle CO less
than 1%. High CO appears to inhibit CO conversion over catalysts which are
active under low CO conditions.
This inhibition of CO oxidation at high CO concentrations (greater than
1%) for catalysts in actual field use agrees with laboratory studies on CO
oxidation over supported noble metal catalysts. Kinetic studies (24-27)
indicate that CO oxidation is first order in CO below ~100 ppm CO (at approx-
imately one atmosphere reactor pressure), negative order in CO above ~1% CO,
but there is a wid« disagreement in the 100 ppm to 1% CO range for the temper-
atures at which automotive catalytic converters operate. Uncertainty in this
concentration range partially involves the transition from first to negative
-order kinetics, but above kinetic studies of this reaction system explain
this uncertainty to be a result of the existence of multiple steady states.
Various researchers (30-32) attribute this multiplicity to intraparticle
diffusion effects, although recent experimental work (26, 33) points to
surface-phenomena-based explanations for the multiple steady state (or
hysteresis) behavior.
The cited experimental evidence indicates that CO oxidation over noble
metals is first order in carbon monoxide at low concentrations. As CO level
is increased, a critical CO concentration is reached at which a rapid tran-
sition to negative order CO kinetics occurs, accompanied by a large decrease
in the oxidation rate. These laboratory results corroborate our field studies
where steady-state test segments with high CO concentrations exhibit very
poor carbon monoxide conversion, even though the oxygen content of the exhaust
62
-------
stream (> 27. 02) favors more complete CO conversions in the catalytic
converter.
It appears that the high CO levels found at idle in improperly tuned
cars doubly impairs the operation of automotive catalyst systems. Not only
do these high idle CO levels place a large load on the catalytic converters
in terms of pollutant mass input, but the existence of these high CO levels
forces converter performance into a regime characterized by inefficient
operation relative to original design specifications.
63
-------
SECTION 7
SULFUR DIOXIDE EMISSIONS
INTRODUCTION
Most sulfur present in gasoline is emitted from the engine as S02« As
exhaust gases pass over the catalyst some of this SO2 may be oxidized to SO^
which will quickly combine with water vapor in the exhaust to form sulfate
aerosol particulatc upon cooling. Other sulfur compounds may form in catalysts
(34, 36) (e.g. -h"2s» COS) and though these, if formed, could have important
consequences, they probably do not constitute a significant percentage of the
total fuel sulfur throughput. SOo in the exhaust can also interact wit i the
catalyst resulting in storage and/or release of sulfur compounds, again
principally as S02. Thus, measurement cc S02, though not a complete analysis
of sulfur compounds or the primary focus of the study, can provide insight to
the dynamic catalyst behavior during various vehicle test modes.
S02 was monitored continuously in dilute exhaust. SO2 mass emitted during
any particular test segment was obtained by integration of S02 concentration
and the known CVS flow. Separate SO2 mass emission values were obtained for
the 5 minute idle periods and the actual test segments. Details of this
detection system are given in Section 8.
S02 PURGE AT IDLE
Two distinct S02 emission patterns were found in the 5 minute Idle periods
separating the various te:..: modes. The first pattern is characterized by
insignificant S02 emission in idle periods, consistent with low fuel consumption
and correspondingly low sulfur throughput. S02 emission dropped raonotonically
to these idle values when the vehicle was decelerated from either the 50 mph
cruise or CFDS.
The second S02 emission pattern is characterized by a significant release
of S02 during the deceleration to the five-minute idle period following com-
pletion of the 50 mph cruise or CFDS. Based on fuel sulfur throughput during
idle, this quantity of S02 can on.ly represent the release of previously stored
sulfur from the catalyst. This S02 purge is characterized by a maximum
emission level up to twcncy-fivs times the stabilized SO2 level attained
during 50 mph cruise. Representative purges in the idle following a CFDS
cycle usually exhibit ~.iximuro SO? emission rates of less than one-half those
associated with the 50 mph cruise, and arc found to begin during the final
idle of the CFDS. Within a given test, there is a reasonable consistency of
purge magnitudes for all CFDS cycles. A correlation was found between the
magnitude of S02 purge and idle CO levels. For example, for all three tests
64
-------
through 12,753 miles, Car 3 exhibits S02 emission behavior similar to the S02
trace from Test 41 in Figure 38. Very little SC>2 release is observed during
idle periods from this vehicle, characterized by low idle CO. At Test 57 at
20,000 miles this car showed high idle CO and a dramatic change in S02
emissions pattern occurred, also shown in Figure 38. Large~SO2 purges are
noted during idle periods for this vehicle exhibiting high idle CO.
One percent idle CO is an approximate cutoff value separating small and
large idle S02 purges. In order to quantify purge phenomena, S02 concentra-
tions in the dilute exhaust were integrated during each driving cycle and idle
period, yielding corresponding S02 mass values for each segment. A ratio of
these masses was defined as follows:
idle purge SO9 macs
SOo purge fraction = ,,_ f g f .. _.
* r ° previous cycle S02 mass + idle purge S02 mass
Vehicles with idle CO values greater than 1% yield larger purge fractions than
those with lower CO values, as illustrated by Figures 29 and 40 for post-50 mph
cruise and post-CFDS cycles, respectively.
TOTAL SULFire RECOVERY
Total ilfur recoveries for a given cycle were calculated r.s the sum of
sulfur output in the form of cycle sulfate and S02, as compared to sulfur input
..computed from fuel analysis multiplied by fuel consumption for the cycle. In
general, total sulfur recoveries were considerably less tlian fuel sulfur input,
averaging 32% for all 50 mph cruise tests. When idle purge S02 was included,
an average of 457. of fuel sulfur was recovered. Corresponding values for the
CFDS were 587. and 77%, respectively. Several factors have been considered in
an attempt to resolve the difference between fuel sulfur input and measured
sulfur species output, but no single satisfactory explanation has been found.
Although it is unlikely on the basis of investigation, the most simple
explanation would be a systematic error in the SO2 detection system. More
likely are the complexities of long-term sulfur storage and release of
different sulfur compounds in relation to the specific driving cycles of the
laboratory test, and over-thc-road use. In either case, purge fraction is
essentially unaffected, being only a relative measure of when S02 emission
occurs in the test driving cycle.
The magnitude of the idle purge in relation to fuel sulfur input is
demonstrated in Table 22 where the ratio of idle period purge S02 to fuel
sulfur input to the catalyst in the preceding cycle is tabulated as "S02
purge sulfur recovery (7.)". Marked differences are apparent in purge magni-
tude for tests with idle CO less than and greater than 17.. Total fuel sulfur
recoveries are also listed in Table 22. These ''total cycle sulfur recoveries
(7.)" include the S02 purge contribution fron the idle following each cycle.
A few vehicles exhibit high CO emissions during the 50 mph cruise (Table
3). Compared to similar vehicles with low CO emissions in the 50 mph cruise,
these high CO emitters exhibit lower idle S02 purges even though both are
65
-------
--
Figure 38
PURGE OF S02 FROM CATALYST
10-
6-
i
4
la,
Ul
UJ 0
t
_J
O
-10-
CL
a. 8-
cvl
O
W g.
4-
2
0
1975 PLYMOUTH
440 V8/A3
12,753 miles
IDLE CO = 0.2%
TEST 41
FTP
' rf
50 MPH CRUISE
5 MIN IDLES .
1975 PLYMOUTH
440 V8 'A3
20,200 miles
IDLE CO = 7.0%
TEST 57
i "''"-."
_.
NO PURG
f
fliM
SET-7
E ATIDL
.J»
SET-7
E
IDLE PURSE OF S02
i^**"
i */
^| »
^
J*k
SET-7
A
,AA
SET-7
^SA^J
^U
SET-7
l\
1
f
3
30 60 90 120 150 180 210 240
TIME (min.)
-------
Figure 39
0.60
^
§
fc
^
^
«S °-40
0.20
0.00
S02 PURGE FRACTIONS
BY IDLE CO LEVEL'
SOmph CRUISE
.
IDLE K
' '0
IDLE T
CO>1%L
w/////m.
-
^
jg
NJ
^^M
~|
_J
1
MONOLITH MONOLITH PELLETED
W.O AIR PUMP W AIR PUMP W.O. AIR PUMP
-------
Figure 40
0.60
0.40
0.20
o.oo
SOz PURGE FRACTIONS
BY IDLE COT LEVEL CFDS
C0<1% fcSI
C0>1% I I
MONOLITH
W 0 AIR FUMP
MONOLITH
W. AIR PUMP
PELLETED
W.O. AIR PUMP
-------
Table 22
Fuel Sulfur Recovery
Category
S0; Purge Fraction SO., Purge Sulfur -RecoveryQO Total Cycle Sulfur RecoveryC/.)
SOmph Cruise CFDS Cycle SOmph Cruise CFPS Cycle SOmph Cruise CFDS Cycle
A) Monolith Without
Air Pump
(111 tests)
All Tests 0.39
CO < 1% 0.24
CO > 1% 0.44
B) Monolith With
Air Pump
(37 tests)
All Tests 0.11
CO < 17. 0.07
CO > 17. 0.17
C) Beaded Without
Air Pump
(72 tests)
All Tests 0.39
CO < 1% ' 0.12
CO > U 0.62
0.22
0.16
0.25
0.13
0.06
0.24
0.29
0.09
0.49
15.3
8.0
17.8
5.3
2.0
10.1
13.6
2.4
24.8
16.5
11.8
18.2
9.2
3.6
17.3
20.6
5.7
35.5
45.2
41.8
46.5
57.2
49.7
68.2
33.8
22..
44.7
77.2
76.1
77.6
76.8
76.7
77.0
67.1
64.2
70.1
-------
characterized by idle CO in excess of 1%. Finally, a comparison of tests
performed at low mileage (< 15,000 miles) and high mileage indicates no
statistically significant effect of mileage accumulation on SC>2 purge behavior.
DISCUSSION OF S02 PURGE PHENOMENA
Comparison of occurrences of S02 purges during idle periods characterized
by high CO levels provides a basis for relating SC>2 purges and catalyst opera-
tion. With this connection taken into consideration, analysis of catalyst
operation under high CO level conditions points to two plausible hypotheses
for the existence of SC>2 purges.
Parametric temperature sensitivity of the reactor system to relatively
small changes in converter inlet conditions (i.e. CO concentration) may
explain these S02 purge patterns. However, temperature data obtained since
our earlier analysis(ll) of this S02 release mode indicate that catalyst
temperature excursions do not appear to be sufficient in most cases to accou.it
for release of significant S(>2 during idle periods. Even though CO loads on
the catalyst systems are sufficiently high, the very low conversions character-
istic of the negative order CO kinetic regime do not result in heat production
rates large enough to yield significant temperature increases within in
catalyst substrate.
An alternative explanation of the occurrence of S02 purges focuses upon
surface phenomena characteristic of supported noble metal catalysts operating
fn the presence of high lex-els of carbon monoxide. CO oxidation at these
conditions appears to be negative or.ler in CO because of the strong adsorption
of CO on platinum relative to other species present in the engine exhaust
stream(24, 25, 26). As gas phase CO concentrations increase, surface coverage
by adsorbed CO (on Pt) increases to the point where adsorbed Oo (necessary
for the oxidation reaction) is displaced by adsorbed CO, thereby reducing the
CO oxidation rate. Our evaluation of the pertinent Langmuir-Hinshelwood type
rate equations for CO oxidation indicates that the surface coverage of
adsorbed oxygen in the catalyst falls off faster than the corresponding rise
in CO surface coverage with increased gas phase CO levels. Therefore, bince
the CO oxidation rate is proportional to a product of 02 and CO surface
coverages, the overall CO oxidation rate falls off with increasing CO gas phase
concentration at high CO levels. If high CO levels strip the catalytic surface
of adsorbed 02, the same phenomena can occur with adsorbed S02 and other sulfur-
bearing species.
The following scenario is proposed to explain the purge of S02 after
deceleration to idle in the presence of high idle CO levels. The large
increase in gas phase CO concentration coincides with deceleration to idle
results in a much greater concentration of CO on the catalyst surface than
characteristic of non idle operation during the previous test cycle. Catalyst
surface coverage by CO becomes so large that significant amounts of adsorbed
02( M>2 and possibly other sulfur-bearing species are quickly stripped off
the catalytic surface and dumped into the converter gas stream, creating an
S02 purge. This surface phenomena model of S02 purges is supported by the
finding that purge magnitude correlates with idle CO concentration.
70
-------
Also in agreement with the above proposed hypothesis is the observation
that no significant S02 purges were found for vehicles exhibiting high CO
emissions during the 50 mph cruise despite the high idle CO exhibited by these
same vehicles. If the exhaust during the 50 mph cruise has high CO levels,
then the corresponding large CO surface coverages limit the amount of S02
adsorbed during the 50 mph cruise. The advent of high idle CO during the
subsequent idle period does not result in a S02 purge because very little
adsorbed sulfur is available for stripping off into the gas stream during
idle.
71
-------
SECTION 8
EXPERIMENTAL PROCEDURES AND EQUIPMENT
EMISSIONS TESTING
Background
This study was initiated in response to the need for data on sulfate
emissions from catalyst cars during extended periods of mileage accumulation
in consumer use. Regulated emissions, fuel consumption, non-sulfate particu-
late, and tune-up parameters were also of interest for cars in the study since
1975 marked the public introduction of oxidaLive catalyst emission control
technology. The testing sequence adopted to obtain these data at each vehicle
test point is shown in Table 23. In the course of two and one half years of
data collection, modifications were incorporated to this initial test protocol.
These changes are listed at the bottom of Table 23 with the vehicle test
number at which the change was instituted. Table 24 shows the typical time-of-
day schedule for the various test segments.
Vehicle Check-In and Soak i
i
Fuel and Hour Meters
Upon introduction to the test group, each vehicle was outfitted with an
engine hour meter (Engler Instrument Co., Model J12N6) and a totalizing fuel
meter (Service Recorder CO., Service Oil Meter). These meters remained on
the vehicle throughout th». project. A typical fuel meter installation is
shown in Figure 41. The fuel meter is a positive displacement type (no
minimum flow requirement) with an accuracy of + 17.. Fuel meters and a pro-
tecting fuel filter were installed between the fjel pump and carburetor. The
hour meter was connected to the ignition switch and was in operation whenever
that switch was in the "start" or "run" position.
Tank Fuel Sample
Vehicles were tested in "as received" condition such that owner's tank
fuel was used whenever possible. Since the length of each tesc was approxi-
mately 120 miles, the vehicle- tank, had to be at least 1/2 full prior to
testing. When vehicles were delivered to AEL with insufficient fuel for the
entire test sequence, enough additional conuiercial lead-free gasoline was
added (and recorded) from the AEL fuel facility to perform the test. When
sufficient fuel was in the tank, a one gallon sample was pumped, as shoxm in
Figure 42. These fuel samples were shipped in lots of 10 to the EPA Sourer.
Fuels and Molecular Chemistry Section in Research Triangle Park for analysis
72
-------
TABLE 23
Data List for Each Emissions Test
Test Segment
Measurements
Vehicle Check-In before 12-20 | Idle HC, CO; Engine Analyzer Check-in
Hour Soak
(ignition, timing, power balance, EGR,
etc.) Visual emission system integrity.
Tank fuel sample: Sulfur, Lead, Phos-
phorous, Manganese, Reid Vapor Pressure,
API Gravity, Density, Distillation
(Mote 1)
Odometer, Engine hour meter, totalizing
fuel meter.
1975 FTP
Gaseous emissions: HC, CO, NOX, C02, S02
One 47mm fluoropore filter for entire
FTP: Total particulate mass, Soluble
sulfate by Barium Chloranilate (EGA)
SC>2 trace in dilute exhaust and mass by
continuous integration.
02 continuous trace in raw exhaust.
1-Hour - 50 MPH Cruise
Same as for FiT? with 1 additional 47ram
fluoropore filter for Particulate
Elemental Analysis by X-ray Fluorescence:
Aluminum, Phosphorous, Sulfur, Calcium,
Iron, Copper, Bromine, Zinc, Platinum, Lead
and Manganese. Anions: Cl~, Br~
Fl", NOo" by 1C.
5-Minute Idle Periods
SO2 trace, mass by continuous integra-
tion. Soluble sulfate mass by BCA from
47mm filters collected; A) one filter
for first idle after 50 cruise and B)
last 3 idle periods averaged on single
filter (Note 2)
Five CFDS cycles followed by
5-minute idle periods
(Note 3)
Sane as for FTP.
HFET (Note)
Same as for FTP,
Three, 15-minute steady state i HC, CO, C02, 02 and temperature before
(Idle, 30mph, 50mph) raw | and after catalyst during last 10 minutes
exhaust tests (Note 5) j of each segment.
NOTES: 1) Added nanganeso analysis from tank fuel after test #149, 12/76.
2) Dropped idle filters af^er test #162, 3/77.
3) Dropped last thre= CFDS segments after test #162, 3/77.
4) HFET segment added at test #218, 8/77.
5) Added steady state converter performance segments at
test #218, 8/77.
73
-------
Table 24
Test Day
TVpical Time Test Segment
2:00-4:00 Deliver loan vehicle and pick-up test vehicle.
3:00-5:00 Check-in test vehicle, collect fuel sample,
initiate cold soak, weld pores for raw exhaust
test, swap tires.
7:00-9:00 Begin FTP testing.
9:00-10:00 Begin one hour 50 mph cruise.
10:00-11:00 Begin CFDS cycles.
11:00-1:30 Begin HFET and before/after catalyst tests.
12:30-2:00 Prepare test vehicle for owner return.
1:00-3:00 Return test vehicle, pick up loan vehicle.
-------
Figure 41. OTR Fuel Meter Installation.
. .... ^ _ t^j^r-
Figure 42. Collection of Tank Fuel Sample.
Photography by Robert Johnson
75
-------
Analyses performed were: Sulfur, Lead, Phosphorous, Reid Vapor pressure, API
gravity, density, and distillation. Analysis for manganese was added in
December 1977.
Engine Analyzer ~
Figure 43 shows a typical engine check-in progress. Engine and idle
emission parameters were recorded on a check-in sheet shown in Figure 44. The
engine analyzer was a Sun Model EET940. A Sun "EPA-75M" HC/CO analyzer was
used through most of the project, but was replaced by a Horiba Mexa-300
analyzer for the last six months of testing. Both instruments were ini-ially
calibrated against NBS traceable gases and checked with working gases period-
ically thereafter. EGR valve operation was checked by manual application of
vacuum to the EGR valve with observation of drops in manifold vacuum and
engine idle speed confirming its operation.
Cold Soak Preparation ~
After check-in, the vehicle was prepared for cold soak. During winter
months front and rear wheels were swapped to avoid testing with snow tires,
many of which were studded. The dynamometer tire pressure was set at 35 psi
for all tests. The checked-in vehicle was normally placed in cold soak about
4:30 p.m. for testing the next morning. The FTP portion of the test sequence
normally began about 9:00 a.m., resulting in 14-16 hours of soak. Vehicles
were moved to the test bay from the cold soak bay by a car mover shown in
operation in Figure 45. Vehicles were soaked in a climate controlled room
with a maximum/minimum temperature thermometer adjacent to the car. Soak
temperature control set point was 72°F, with an extreme minimum of 6b°F and
extreme maximum of 75°F throughout the two and one-half years of testing.
For the final test on all but 13 vehicles, raw exhaust sampling and
temperature measurements before and after the catalyst were added. Sample
ports were welded into the exhaust system to obtain these data as shown in
Figure 46.
Emissions Testing Equipment
Test Bay \
I
The AEL test bay is shown in Figures 47-49. Two air conditioner/electric
heater/humidity control units circulate 15,000 cfra of room air through over-
head ducts parallel to the vehicle as positioned on the dynamometer. Tempera-
ture control was maintained at 22 + 2°C regardless of test mode or seasonal
variation; humidity control was less responsive to load changes, and was set
at 507. relative humidity with a range of 30-60% RH bracketing all test condi-
tions. The dynamometer used for testing was a Clayton CTE-50-full lift,
equipped with automatic road load and direct-drive variable inertia simulation.
A Hartzel Model N24-'JW fan (525t) cfm) was directed at the front of the
vehicle. A 20-inch squirrel cage blower (7000 cfm), Dayton Model 3C011, was
directed diagonally from the drivers side of the vehicle toward the rear
wheels. This blower is located behind the converter to provide rear-tire
76
-------
I
Figure 43. Vehicle Check-In.
77
, \
-------
Figure 44. Vehicle Check-In Log Sheet
AUTOMOTIVE EMISSIONS LABORATORY ($18) 1*57-3200
New York Slate Department of Environmental Conservation
SO Wolf Road. Albany. New York 12233
ENEIhc ANALYSIS CHECK IN SHEET
TEST NUMBER TEST BATE. , DATE VEHICLE
MAKE
START
IDLE
CRUISE
ACCEL-
ERATION
HIGH
SPEED
COHM
^
^B
m
^
w
MODEL TEAS
TEST PROCEDURE
Cranking Voltage
Cranking Coil Output
Cranking Vacuum
Idle Spaed
Dwell
Initial Timing
Hydrocarbon* PPM.
Carbon Monoxide
PCV Tail
Manifold Vacuum
Dwell Variation
Con Polaniy
Spark Plug Firing Voltage
Mr. 'Tium Coil Output
Secondary Circuit Insulation
Secondary Circuit Condition
Coil and Condenser Condition
Breaker Point Condition
Cam Lob* Accuracy
Hydrocarbon* P. P M.
Carbon Mor-oxide Percent
Cylinder Power Balance
Record R P.M.
Bpa'k Mugs Under Load
kccrlerator Pump Action
Timing Advance
Charging Voltage
NydrocaiBons PPM
Carbon Monoxide P -re- «
Exhaust Restrictiori
READ
Voltmeter
Scope (Display)
Vacuum Gauge
Tachometer
Dwell- Meter
Timing Advance Unit
Hydrocarbons Meter
Carbon Monoxide Meter
Carbon Monoxide Meier
Vccuum Gauge
Dweil Meter
Scone (D-splav)
Scope (Duplex)
Scope pispisv)
Sccoe ;Dispiav)
Scope (Raster)
Scope (Rare')
Scope (R«:er)
Scope (Superimposed)
Hydrocarbons Meter
Caibon Monoxide Meier
Tachometer
1 12 |3
SPECS.
'Illllllli
RESULTS
'/////////
GOOD
BAD
4 IS 16 |7 |8
Scope (Display)
Caibon Monoxide Meter
Timing Advance Unit
Volirneu-r
Hydrocarbons Meier
C-TOon Monoxide Meier
Vacuum Gauge
1 |
1
LNIS :
78
-------
Figure 45. Car Mover Operation.
Figure 4t. Bcfore/Afl-:r Catalyst Sample Ports,
i
79
\
\
\
M
i
-------
J
Figure 47. Emissions Test Bay.
80
' '
\
>
.w. .'*.-.
-------
-** .-. - ; .^.* «_
,. m
-i -**-Ti^-»/-- j
Figure 48. Dynamometer, Cooling Fans*
Figure 49. Exhaust Sampling Equipment,
. 81
-------
cooling in order Co prevent tire failure. These fans are shown in operating
position in Figure 48.
Particulate Collection and Exhaust Handling
Exhaust particulate was collected in a standard dilution tunnel(37, 38)
connected between the ir.let of the Scott model 302 positive-displacement-pump
constant-volurae-sampler (CVS) and the vehicle exhaust inlet. CVS flow was a
nominal 400 cftn. The dilution tunnel and particulate collection probes are
shown schematically in Figure 50. Dilution air inlet to the standard filter
box was ducted from the exit of one of the test bay air conditioners. Parti-
culate was collected through two probes (1 in I D x 6 In lengths) into 47 ram
Millipore filter holders. These probes and filter holders were rigidly
mounted by a quick disconnect clamp to a 6 in diameter probe access port on
the dilution tunnel. The probes are shown in Figure 51. Flow control through
the probes was regulated by 10-turn Parker-Hannifin (N-800-B11) valves. Flow
rate was monitored by Brooks model R-8M-25-2 flow meters. A vacuum gauge
between the filter and the control valve was used to make pressure corrections
to compute total volume filtered.
The CVS was outfitted with 9 sets of exhaust/background bags to accom-
modate the test sequence without delays for bag evacuation. Background
sample was collected from the dilution air filter box. CVS blower differential
and absolute pressures were measured on Merian 10AA25WM-36 and 2QAA25WM mano-
meters, respectively. CVS blower inlet temperature was continuously recorded
on a Rustrack Model 2133 tiwnuistor probe strip chart recorder.
Gaseous Analysis
Bag analysis of HC, CO, C02» and NOX followed the Federal Register sample
conditioning and analysis procedures for the 1975 FTP(13). Instruments used
for exhaust gas analysis are listed in Table 25.
Oxygen concentration in undiluted exhaust was determined by sampling at
the inlet to the dilution tunnel (see Figure 50). The 02 measurement system
is schematically sliown in Figure 52.
*
S02 mass emissions were determined by continuous measurement and elec-
tronic integration of SC>2 concentration in dilute exhaust, sampled at the
dilution tunnel particulate filter station (see Figure 50). The SO2 measure-
ment system is shown schematically in Figure 53. Output signal from the
SM-1000 UV spectrometer was integrated electronically and also strip chart
recorded by Disk integrator to provide hard copy output of where S02 emission
occurred in any test segment. Large purges of S02 in idle periods were
observed in the early tests, and an electronic switching system was designed
to restart the continuous electronic integration procedure in synchronization
with the CVS bag switches. This switching system, shown in Figure 54, per-
mitted the SO2 mass to be determined for successive back-to-back test segments.
Emission Test Procedures
Dynamometer
Dynamometer calibration was established both by recommended Clayton
82
-------
8
Dilution Air
From Air Conditioner
Porticulate Collection
(2 Duplicate Systems) Vent
Constant Volume Sanr'er
Bag
Analysis
Sample Port
Flow
Restriction
Figure 50. SCHEMATIC OF EXHAUST HANDLING AND
PARTICULATE COLLECTION
-------
Figure 51. ParticuLate Sample Probes
-------
Table 25
Exhaust Gas Measurement Instrumentation
00
Ul
Gas
CO
CO
C02
CO 2
02
HC
NOX
S02
CO
C02
1IC
Manufacturer
Ethyl-Intertek
Horiba
Ethyl-Intertek
Horiba
Scott
Scott
Scott
Lear-Seigler
Beckman
Beckman
Beckman
Model
URAS 2T
AIA-21-AS
URAS 2T
AIA-21
150
215
125
SM-1000
315
864
400
Type
Instrument
ND1R
NDIR
NDIR
NDIK
Paramagnetic
FID
Chemiluminescence
2nd dcrivitive UV
Spectrometer
NDIR
NDIR
FID
Notes
Replaced URAS after test #161
Replaced URAS after test #249
Used for before/after
converter tests
-------
Refrigerator
Raw
Exhaust
00
a*
Water Removal
1CFM
Pump
Ballston
Filter
Strip Chart
Recorder
Bypass
Paramagnetic
02 Meter
Figure 52. OXYGEN IN RAW EXHAUST SAMPLE SYSTEM
-------
Exit
Temp
Control
110°
Sample Cell
Raw Exhaust
Mace Teflon Filter
Fluoropore Filter Media
Lear-Seigler
SM1000
SOZ
Strip Chart
Figure 53. S02 MEASUREMENT SYSTEM
-------
00
00
FILL BAGS
CVS
CVS
wiring
CIRCUITS
Oplo-
iietotor
Logic
Pulse
Animating between these two sets of CVS switehfo produces a pulse
to print the integrated count and reset/restart the counter
Negative
Pulse
Figure 54. S02 ELECTRONIC INTEGRATION SWITCHING SYSTEM
-------
caii brat. io procedures ai:ci by c-ost -do'.T. procedures as specified in the Federal
Hegi.;ter. rhre*» compler-* roast-dowi calibrations were -performe-j in rhe course
of tnis we./.. Daily checks on the 50 nuh power absorbtion as port of dyna-
mometer warr*-up were used to verify st.->< If ty cf calibration. Two Drivers
aides were used, and the-je were zero checked ar.H calibrated at 50 mph as part.
of Lhe daily dynamometer preparation. A Scott Model 201 drivers aide was used
for FTP testing, and Varian A- 4 drivers aide was used for the CFDS tests.
Inertia settings were assigned to test vehicles based on new car certification
test data published in the Federal Register (40CFR 3/11/75, 41CFR46 3/8/76).
Particulate Collection
Hot-wire anemometer measurements were used to measure the flow profile in
the dilution tunnel at the particulate sampling station. These experiments
verified a flat velocity distribution consistent with fully developed turbu-
lent flow. Mixing of exhaust gas and dilution air was also characterized by
injecting propane in the exhaust inlet to the tunnel at a constant rate while
performing a traverse of propane concentration across the diameter of tunnel
at the particulate sample station. A uniform propane profile was observed
indicating satisfactory mixing. The tunnel was swept and washed at 6 month
intervals with the debris sent to EPA for analysis. Fluoropore filters, 0.5
micron pore specification, were used for particulate sampling throughout this
study. Flow adjustment was frequently required to maintain constant flow as
filters became progressively loaded. Vacuum measurements were recorded and
used to correct observed flow to standard conditions. A dry gas meter was
connected to the exit of this by stem for several tests in order to confirm
the accurate determination of total filter flow.
Constant Volume Sampler
The Scott Model 302 constant volume sampler (CVS) was extensively flow
calibrated using an Autotronics Inc. turbine flrv meter (Model 1000 flow com-
puter and Series 100 flow transducer) prior to the beginning of this project.
A minute change in calibration was observed for the one additional flow
calibration performed during the course of this project to check the system for
long-term drift.
Three CVS blower revolution counters were used -on .an alternating basis
as part of the daily propane injection test to check for any deterioration of
counter accuracy. Propane injection tests through test #218 were by a gravi-
metric determination using lecture bottles of propane suspended .from an Ohaus
balance (Model 71032). Tests beyond #218 used a Horiba critical flow orifice
device (CFO model 201). A + 5% propane recovery error cutoff was utilized,
but this error bound was decreased to + 2% without any CVS or instrument
calibration changes when the CFO device replaced the cumbersome gravimetric
method.
Analytic? 1 Instruments
tor jnalysli of '1C, CO, CO;. N0X, and 02 v*re calibrated on
a riorrlily h«.'i.is with laboratory standards. These standard gases were + 2%
from '.he mar.<_facL:ir<> t'.::s* were. t.alilratfid by the EPA Mobile Sources
89
-------
Laboratory in Ann Arbor, Michigan. From these primary calibration gases,
working span gases were establisned for daily use. Zero, span, and gain
settings were checked as part of the daily preparation before testing, and
between test segments. Strip chart recordings were used to determine instru-
ment response and provide a hard copy of all calibration, zero, span, and
emission determinations. NOX converter efficiency was checked as per Federal
Register (40CFR Ft. 86) as part of the monthly calibration. Instruments were
operated continuously to obtain maximum stability. The URAS-2T CO instrument
required the removal of t^O and CC^; two banks of Ascarite/Drierite columns
were used for all determination on that instrument.
The Lear-Seigler SM-1000 second derivative UV spectrometer was set at
301 nm to detect SO* in dilute exhaust. The instrument was supplied with a
servo-operated ampule containing SO2 as a calibration. A series of tests using
gravimetric injection of pure 3O2 to the exhaust inlet of the dilution tunnel
analogous to a propane injection test confirmed the operation of the system.
S02 calibration gas was also used directly in the instrument to set the instru-
ment calibration factor. The internal S02 span ampule was calibrated from this
gas calibration and used for a daily span check. A wet chemical method for
SO2 determination(14) was also used to check for interference from other
exhaust species. This method absorbs SO2 into 37, H202 as sulfate for subsequent
determination by the BCA system used for determination of particulate sulfate.
Several vehicle tests with parallel Lear-Seigler and bubbler tests confirmed
the instrument calibration and the absence of major interference by other
exhaust species.
Laboratory Analysis of Particulate
Filter Handling
All particulate samples were collected on 47 mm diameter Fluoropore 0.5
micron pore size media. Fresh filters from stock were stabilized overnight in
a dessicator containing drierite prior to initial weighing. Filters were
weighed on a micro-balance housed in a controlled humidity and temperature
glove box, shown in Figure 55. Each filter was placed in a numbered petri dish
upon weighing and transported to the vehicle test bay in groups of 20 filters.
After completion of a test segment filters were immediately returned to the
petri dish. The eight filters from each completed test were placed in a
dessicator containing dilute NH&OH vapors for a minimum of 1/2 hour, to
stabilize particulate H2SO^ as (NH4>2 SO^. The ammoniated filters were then
placed in a dessicator containing drierite overnight in order to remove water
associated with the particulate H^SO^. Since the anxnoniation step changes the
filter loading according to the amount of l^SO^ present, subsequent sulfate
analysis results were used to compute the NH^+ mass to be subtracted from the
total particulate mass to arrive at the mass of water free particulate col-
lected.
- Filters were individually placed in 50 ml Poly-cons with 20 ml of 607.
isopropyl alcohol to solublize sulfate. The samples were mechanically agitated
for one hour prior to filtering the extractate through Whatman #40 filters in
preparation for sulfate measurement.
90
-------
Figure 55. Microbalance for Particulate Mass.
91
. v..
.
\
-------
Soluble Sulfate by BCA -.
The semi-automated barium chloranilate (BCA) method of Tejada and Sigsby
(39) was used for determination of soluble sulfate loadings on the filters.
Figure 56 shows -he system in operation, while Figure 57 is a schematic of the
system. Detectio.. of soluble sulfate occurs by passing liquid sample through
a column packed with barium chloranilaLc; barium sulfate is then formed, re-
leasing chloranilate which is quantitatively detected by a UV detector set at
310 run. The instrumentation used here was a Technicon Samplpv IV and Propor- ,
tioning Pump III, Valcor 5-port air actuated valve, Instrumentation Specialties
Co. high pressure pump, pressure monitor (# 1.590), flow controller (#314), and
absorbance monitor (#UA-5). A Hewlett-Packard 7100B strip chart recorder in
parallel with a Columbia Scientific Supergntor II programmable integrator
provided necessary output.
Prepared filter extracts were loaded in the Technicon carousel sample
holder with several blank solvent and calibration samples of (NH^)2SO^. The .
BCA apparatus was operated on a 6 min cycle, with 4 rain to fill the sample '
loop and 2 min to inject the sample. The BCA column was 1/4 in x 3 in stain-
less steel, the injection loop 1/16 in x 3 in stainless steel, and high
pressure pump rate was 100 ml/rain. Integrated peak areas from the calibration
standards were used to generate a 2nd o'ier polynomial fit calibration curve
for each batch of samples (usually 2 complete bar tests). Soluble sulfate ,
values for the samples were computed based on this calibration curve. XRF '
and Ion Chromatograph analyses of filter samples indicated that interferences
of other ions with BCA sulfate determinations were negligible for filters in
this study.
Elemental Analyses by XRF
Elemental analyses of particuiate were performed on a Siemens wavelength-
dispersive x-ray fluorescence (XRF) spectrometer shown in Figure 5, The
basic XRF unit was equipped with a model &- x-ray generator and a 10-position
carousel filter holder. One 47 mm dia ammoniated filter from the 1-hour 50 raph
cruise was used for XRF analyses. Ten elements were measured; bromine, lead,
zinc, copper, iron, sulfur, calcium, phosphorus, aluminum, and manganese. The
XRF system was calibrated with standards purchased from Columbia Scientific
Industries. Multiple standards were used for each element from which a least
squares calibration line was calculated. Correlation coefficients for these
calibration lines were typically 0.999, indicating excellent linearity to the
lower limit of detectability. Some additional calibrations were performed for
light elements (sulfur, phosphorus, manganese) by deposition of aerosol particu-
late on fluoropore filters. These filters were analyzed both by XRF and atomic
absorbtion to establish calibration.
Comparison of BCA, XRF and Ion Chromatograph Sulfate Methods
To check the integrity of BCA sulfate results, the duplicate 50 mph cruise
filters previously used for XRF elemental analysis were analyzed for sulfate by
ion chromatography(23) at the end of the project. A valid comparison of sulfate
values from simultaneously collected filters required an p^lo-irce for una\ *.i j
92
i
-------
Figure 56. BOA Apparatus Set-Up.
-------
Techntcon IV
Sample
Holder
uv
Detector
i i
UV
Absorbance
Monitor
Discard
Electronic
Peak
Area
Integrator
Sample
Injector
Loop\
Fill Loop/ Solvent Baseline
Inject Sample
Figure 57
SCHEMATIC FOR AUTOMATED BARIUM CHLORANILATE SYSTEM
-------
Figure 58. xrf System for Particulate Analysis,
95
-------
able flow differences between the filter used for BCA analysis, and the XRF
filter. An indication of differences between these filters can be seen in a
comparison of specific total particulate loadings as illustrated by Figure 59.
Most of the points far from the diagonal on Figure 59 represent cases where
one or both of ur' filters plugged during the 50 mph cruise. These cases were
not included in the pool of data used for BCA-1C comparisons.'
Figure 60 illustrates the comparison of 1C to BCA sulfate values for those
tests where sulfate responses are above the detectable limit for both instru-
ments and no filter plugging was encountered.
The same filter was used for elemental sulfur determination by XRF and
sulfur in the form of sulfate by 1C. A comparison of these results in Figure
61 indicate that essentially all sulfur on the filters was found as sulfate.
For sulfur mass emission rates above 2 rag/mi, 1C sulfur values were larger than
those determined by XRF.
1
ft.
>
t
96
\
\
-------
"xrf"
filter
emission;;
40.0 -
35.0
30.0
25.0
20.0
15.0
10.0
5.0
0.0
0.0
( -
. * ,-:*
.
S.O 10.0 15.0 20.0 25.0 10.0 1S.O 40.0
EGA filter emissions (mg/mi)
Figure 59* Comparison of Total Par'-.iculate Emissions for Two Probes,
-------
Sulfate
> by 1C
09 Ong/mi)
25.0
20.0
15.0
10.0
s.o
0.0 U
0.0
5.0
10.0 15.0 20.0
Sulfate by EGA (mg/mi)
2S.O
30.0
Figure 60. Comparison of 1C and EGA Sulfate Analysis,
-------
Sulfur
by
1C
(mg/rai)
9.0
1.0
7.0
6.0
4.0
1.0
2.0
1.0
;/
0.0
0.0
l.O 2.0 1.0 4.0 ).0 6.0 1,0
Sulfur by xrf (mg/mi)
1.0 9.0
Figure 61. Comparison of 1C and xrf Sulfur Analysis.
-------
REFERENCES
! Bradow, R.L., and J.B. Moran, "Sulfate Emissions from Catalyst Cars: A
Review11. SAE Technical Paper No. 750090, Society of Automotive Engineers,
Warrendale, Pa., 1975.
2. Begeman, C.R., M.U. Jackson, and G.J. Nebel, "Sulfatr Emissions from
Catalyst-Equipped Vehicles". SAE Technical Paper No. 741060, Society of
Automotive Engineers, Warrendale, Pa., 1974.
3. Trayser, D.A., et al, "Sulfuric Acid and Nitrate Emissions from Oxidation
Catalysts". SAE Technical Paper No. 750091, Society of Automotive
Engineers, Warrendale, Pa., 1975.
4. Creswick, F.A., et al, "Sulfuric Acid Emissions from an Oxidation-Catalyst
Equipped Vehicle". SAE Technical Paper No. 750411, Society of Automotive
Engineers, Warrendale, Pa., 1975.
5* Pierson, W.R., R.H. Hammerle, and J.T. Kunmer, "Sulfuric Acid Aerosol
Emissions from Catalyst-Equipped Engines". SAE Technical Paper No. 740287,
Society of Automotive Engineers, Warrendale, Pa., 1974.
6. Beltzer, M., R.J. Campion, and W.L. Petersen, "Measurement of Vehicle
Parti^culate Emissions". SAE Technical Paper No. 740286, Society of
Automotive Engineers, Warrendale, Pa., 1974.
7. Bradow, R.L., et al, "Sulfate Emissions from Catalyst and Non-catalyst
Equipped Automobiles". SAE Technical Paper No. 740528, Society of
Automotive Engineers, Warrendale, Pa., 1974.
8. Holt, E.L., et al, "0-jntrol of Automotive Sulfate Emissions". SAE Tech-
nical Paper No. 750683, Society of Automotive Engineers, Warrendale, Pa.,
1975.
9. Somers, J.H., et al, "Automotive Sulfate Emissions - A Baseline Study".
SAE Technical Paper No. 770166, Society of Automotive Engineers, Warren-
dale, Pa., 1977.
10. Herling, R.J., et al, "Characterization of Sulfate and Gaseous Emissions
from California Consumer-Owned Catalyst-Equipped Vehicles". SAE Technical
Paper(No. 770062, Society of Automotive Engineers, Warrendale, Pa., 1977.
100
-------
REFERENCES
11. Gibbs, R.E., et al, "Emissions from In-Use Catalyst Vehicles". SAE
Technical Paper No. 770064, Society of Automotive Engineers, Varrendale,
Pa., 1977.
12. Gibbs, R.E., et al, "A Study of Fifty-Six In-Use Catalyst Vehicles". SAE
Technical Paper No. 780645, Society of Automotive Engineeis, Warrendale,
Pa., 1978.
13. 40CFR85; 38FR 16062, June 20, 1973, Effective August 20, 1973, Amended as
shown in Volume 40, Code of Federal Regulations, Revised as of July 1,
1975; 40FR 28066, July 3, 1975; 40FR 33973, August 13, 1975; 40FR 58647,
December 18, 1975.
40CFR86; 40FR 27590, June 30, 1975; 40FR 33973, August 13, 1975; 40FR
58647, December 18, 1975; 41FR 9878, March 8, 1976; 41FR 29389, July 16,
1976; 41FR 31471, July 28, 1976.
14. USEPA, Ann Arbor, Michigan, "Recommended Practice for Measurement of
Exhaust Sulfate Emission from Light Duty Vehicles and Trucks". September,
1977.
15. Irish, D.C., and R.J. Stefan, "Vehicle Sulfuric Acid Level Characteriza-
tion". SAE Technical Paper No.. 760037, Society of Automotive Engineers,
Warrendale, Pa., 1976.
16. Trayser, D.A., et al, "Effect of Catalyst Operating History on Sulfate
Emissions". SAE Technical Paper No. 760036, Society of Automotive
Engineers, Warrendale, Pa., 1976.
17. Krause, et al, "Critical Factors Affecting Automotive Sulfate Emissions".
SAE Technical Paper No. 760091, Society of Automotive Engineers, Warren-
dale, Pa., 1976.
18. Helme, M.P., and W.J. Pienta,- "Idle Emissions from New York Vehicles; An
Analysis Over* Five Years". Presented at 1977 Air Pollution Control
Association Annual Meeting, Houston, June, 1978.
19. 40CFR85; 38FR 16062, June 20, 1973, Effective August 20, 1973, Amended as
.shown in Volume 40, Code of Federal Regulations, Revised as of July 1,
1975; 40FR 28066, July 3, 1975; 40FR 33973, August 13, 1975; 40FR 53647,
December 18, 1975.
20. 1975 Gas Mileage Guide, Second Edition, January, 1975, USEPA/FEA, U.S.
Dtpc. of Energy, Washington, D.C. 20545.
21. 1076 Gas Mileage Guide, Second-Edition, January, 1976, USEPA/FEA, U.S.
Dcpt. of Energy, Washington, D.C. 20545.
\
22. 1977 Gas Mileage Guide, Second Edition, January, 1977, USEPA/FEA, U.S.
Dept. of Energy, Washington, D.C. 20545.
101
-------
REFERENCES
23. Sawicki, E., J.D. Mulik, and E. Wittgenstein, "Ion Chzomatographic
Analysis of Environmental Pollutants". Ann Arbor Science, Ann Arbor,
Michigan, 1978.
24. Wei, J., "Catalysis for Motor Vehicle Emissions". Advances in Catalysis,
.24, 57 (1975).
25. Voltz, S.E., et al, "Kinetic Study of Carbon Monoxide and Propylene
Oxidation on Platinum Catalyst". Industrial and Engineering Chemistry
Product Reseat;h and Development, 12, 294 (1973).
26. Tennant, B., and J. Wei, "Carbon Monoxide Oxidation in a Single Pellet
Reactor". Paper 25a, 70th Annual Meeting of American Institute of
Chemical Engineers, New York, New York, November, 1977.
27. Hlavacek, V., and J. Votruba, "Experimental Study of Multiple Steady State
in Adiabatic Catalytic Systems". American Chemical Society Mvances in
Chemistry Series Number 133, p. 545, Washington, D.C., 1974.
28. Kuo, J.C.W., et al, "Mathematical Modeling of CO and HC Catalytic Con-
verter Systems"* SAE Technical Paper No. 710289, Society of Automotive
Engineers, V.'arrendale, Pa., 1971.
29. Harnet, J.L., "Analytical Evaluation of a Catalytic Converter System".
SAE Technical Paper No. 720520, Society of Automotive Engineers,
Warrendale, Pa., 1972.
30. Smith, T*G., J. Zahradnik, and J.J. Carberry, "Non-Isothermal Inter-
Intraphase Effectiveness Factors for Negative Order Kinetics - CO
Oxidation over Pt". Chemical Engineering Science, 30. 763 (1975).
31. Hegedus, L.L., S.H. Oh, K. Barren, "Multiple Steady States in an
Isothermal, Integral Reactor: ' The Catalytic Oxidation of Carbon Monoxide
over Pt - Alumina". Paper llOb, 70th Annual Meeting of American Institute
of Chemical Engineers, New York, New York, November, 1977.
32. Finlayson, B.A., and L.C. Young, "Mathematical Models of the Monolith
Catalytic Converter: Part III: Hysteresis in Carbon Monoxide Reactor".
Paper HOa, 70ch Annual Meeting of American Institute of Chemical
Engineers, New York, New York, November, 1977.
33. Cutlip, M.B., and C.N. Kenney, "Elementary Step Model and Multiplicity
in Surface Rate Processes". Paper 55b, 69th Annual Meeting of American
Institute of Chemic I Engineers, Chicago, Illinois, November, 1977.
34. Barnes, G.J., and J.C. Summers, "Hydrogen Sulfide Formation Over Auto-
motive Oxidation .Catalysts". SAE Technical Paper No. 750093, Society
of Automotive Engineers, Warrendale, Pa., 1975.
102
-------
REFERENCES
35. Cadle, S.H., and P.A. Mulawa, "Sulfide Emissions from Catalyst-Equipped
Cars". SAE Technical Paper No. 780200, Society of Automotive Engineers,
Warrendale, Pa., 1978*
36. Bradow, R.L,, and F.D. Stump, "Unregulated Emissions from Threc-Way
Catalyst Cars". SAE Technical Paper No. 770369, Society of Automotive
Engineers, Warrendale, Pa., 1977.
37. Somers, J.H., et al, "Sulfuric Acid Emissions from Light Duty Vehicles".
SAE Technical Paper No. 760034, Society of Automotive Engineers, Warren-
dale, Pa., 1976.
38. Ingalls, M.N., K.J. Springer, and R.D. Lawrence, "Automotive Sulfates -
A CVS Compatible Sampling System". SAE Technical Paper No. 780644,
Society of Automotive Engineers, Warrendale, Pa., 1978.
39. Sigsby, J., and S. Tejada, "Determination of Soluble-Sulfate from CVS-
diluted Exhaust: An Automated Method". NIEHS Symposium "Health
Consequences of Environmental Controls", Durham, N.C., April, 1974.
103
-------
APPENDIX A
A punched-tape computer output of the project data base has been provided
to EPA. Request for copies of this tape should be directed to Mr. Peter
Gabel", MD-46, MSERB, EMCD, ESRL, EPA, Research Triangle Park, North Carolina.
Table 26 is a copy of a typical vehicle test output from the punched tape,
and Table 27 defines the variable identifiers from Table 1.
. J
-------
1
TABLE 2fc
Compute i: Output for Typical Emissions Test
itil CAT i,A1L CAF *t- .'.AKE A-.GLLL MILEAGE HiAFS CALS
lul 9 7/2o/7t> l»7i i-LV.-.OU'ih J-uri 2151U.O 3o4.6 o io . 3
*'.F 50-C CFCS 1 CFL£ 2
V-MX 91.82 161.65 94.03 662.45 258.91 259.00
KH 0.90 0.90 0.*2
DF 6.80 12.50 8.85
hC TG 16.82 8.85 5.67
CO TG 511.27 211.21 77.55
NOX .1C 5.93 9.C3 11.20
C02 TG 2287.04 2459.58 2251.97
hC G/H 2.58 0.00 0.00
CO G/H 64.90 0.00 O.OC
NOX C/M 2.4C 0.00 0.00
C02 L/f. 610.22 0.00 0.00
MC 11. 99 0.00 O.CO
LAC 1 STALL 0
CFCS 3 CFCS 4 CFC.L 5
V-MA 256.12 258. 66 258.66
Kh G.S2 O.S2 0.9-1
Lf t.12 8.11 b.26
IX 1C &.4e 9.58 9.62
Co -1C, 124. OC 124.10 122.00
l.tX 'iC 27.22 2o.68 ^7.14
CCI 1C 6815.41 6*02. ID /Oil. 91
III C,/:. 0.70 U.71 0.72
CO C/I-. S.1S S.21 9.C6
NuX C/K 2.02 l.»b 2.C1
0,2 C^ 51C.O- 511. 2', 524.71
i.FO 16. bS 16. tl lb.4l
lit SOC IFC£ 1
Sc2.C/hC\CLE 2.11 10. tS 17.17
SO2 l(/i-j CiC. + ID O.OC 22.47 57.12
i lUtL £ A£ 502 2.46 IS. 10 84. Ob
{AHT ^AES rc/h 0.00 28.03 1.56
£04 tC/1; CYCLE O.CO 4.8'i 0.37
% FULL £ AS S04 O.OC 5.07 0.37
ClitCK IN FtLL
Ci.i.EK 2.0 i i t.T C.OiC
ILLt SFL 650.0 td C/IAL C.OC7
iLbL 1U. 1.0 f C/CAi O.bOL
I DLL liC &CG.G ft.V.t-. S.40G
IDLE CC 7.0 A.t.l. 56.400
Sh MN t.O ^t.NSI'l^ 0.745
£f / AX 1C.U l.B.f- fcS.L'CO
10CO IX 120.0 10 & 121'. COC
IbOC CO i.o 5u fc 221. OCC
FULL ACV l^.u <>C % 1'iS.OUC
lilbj-C IX 12C. 1 Lfr -.C^.bLL
hlS?C CO 0.0 . N G/GAL C.UOo
0, 92 0 . 92
6.12 8.26
4.95 9.06
3.78 122.57
65.44 28.42
25172.17 6996.62
0.09 0.67
0.07 9.08
1.31 2.11
503.44 518.27
17.62 16.60
hFLT
1. 00
0.0.0
U.CO
0.00
O.CO
0.00
C.CO
b.OO
0.00
c.ou
0.00
0.00
OLi 2 CFCS 1 CrtS 4
10. b9. 30.58 30.71
48. 8U 46.24 47. 60
70.76 69.09 7G.*4
O.CO O.OC C.OO
O.OG 0.00 0.00
O.CO 0.00 0.03
XKF ^/K
(A££ U5.E57
E? O.OC7
Fo 0.012
zt. c.o:o
CL O.OGU
FL O.CGC
£ 1.406
CA 0.017
F L.016
AL OiOCC
. N U.COO
G.92
8.12
9.29
121.35
29.49
7106.48
0.69
b.99
2.18
526.41
16.15
CfL£ 5
1C. 11
45. Cb
65.55
0.00
C.CO
0.00
hFtT
C.OO
O.CO
0.00
0.00
O.OC
C.CO
105
-------
Item
Test
Car
Datf.
Mileage
Hours
Gals
v-mx
KH
DF
HC TG
CO TG
NOX TG
O>2 TG
HC G/M
CO G/H
NOX G/H
C02 G/M
MFC
S02 MG/M Cycle
S02 MG/M Cycle- + ID
% Fuel S as S02
Part MASS MG/M
SO* MG/M Cycle
% Fuel S as 804
OWNER
IDLE SPD
IDLE TIM
IDLE HC
IDLE 'CO
SP MIN
SP MAX
1000 HC
1000 CO
FULL ADV
HISPD HC
HISPD CO
TABLE 27
Computer Output Parameter List
Description
Serial number of test
Test group vehicle number
Date of test
Odometer at date of test
Reading from under-hood hour meter
Reading from under-hood fuel meter ?
CVS v-mix (m3) ' '
Humidity correction factor
Dilution factor
Total grams from particular test segment
zf.ro values
missing
indicate
data
ii ii ii n
Emission rate ga/mi
it
ii
n
it
Carbon balance fuel economy
SO2 Emissions rate (mg/mi) - cycle only
S02 Emission rate (mg/mi) - cycle + idle purge
7. Fuel sulfur emitted as S02, includes idle purge
Total Particulate emission, gravimetric (mg/mi)
Sulfate emission by BCA (mg/mi)
% Fuel Sulfur emitted as sulfate
Identifies vehicle source: 0 = AEL, 1 = Red Cross,
2 = NYS Thruway, 3 = NYS Office of General Services,
A = NY Telephone Co., 5 = private
Vehicle idle speed
Spark advance BTDC, negative values indicate retard
HC concentration at idle, ppm hexane
CO concentration at idle (%)
Lowest spark firing voltage (K volts)
Highest spark firing voltage (K volts)
HC concentration at 1000 rpm
CO concentration at 1000 rpm
Spark advance at 2500 rpm minus initial advance
HC concentration at 2500 rpm, ppm hexane
CO concentration at 2500 rpm, 7.
106
-------
TABLE 27
(continued)
Computer Output Parameter List
Item Description
S % WT Sulfur content wt %
FB Lead content gm/gal
P Phosphorous content gm/gal
R.V.P. Reid Vapor Pressure (Ib)
A.P.I. API gravity at 60°F
DENSITY Density at 15°C (gm/cn3)
IBP Distillation Analysis (°F)
10% " "
50% » »
90% " "
EP " »
MN Manganese content (gm/gal)
MASS Total ^articulate emission rate for xrf
filter (mg/mi)
Br, Pb, etc. Emission rate (mg/mi)
i
i
V.
107
\
\
-------
TECHNICAL REPORT DATA
(Please read Instruction! on the re\ erse before completing)
I. REPORT NO.
EPA-600/9-79-047
2.
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
5. REPORT DATE
SULFVTE AND PARTICULATE EMISSIONS FROM TN-USE CATALYST
VEHICLES. Regulated/Unregulated Emissions and Fuel
Economy.
1Q7Q
6. PERFORMING ORGANIZATION CODE
7. AUTMOniS)
8. PERFORMING ORGANIZATION REPORT NO.
R. . Gibbs. G. P. Wotzak. S. M. Bver. and N. P. Kolak
9. PERFORMING ORGANIZATION NAME AND ADDRESS
10. PROGRAM ELEMENT NO.
New York State Department of Environmental Conservation
Division of Air Resources
50 Wolf Reid
Albany. NY 12233
11. CONTRACT/GRANT NO.
R803520-01
12. SPONSORI JG AGENCY NAME AND AOpRESS
U.S. Environmental Protection Agency
Office of Research and Development
Office of Health and Environmental Assessment
Environmental Criteria and Assessment Office (MD-52)
1"** NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
EPA/600/00
16. ABSTRACT
An emissions and fuel economy study of 56 catalyst cars in consumer use and
maintenance has been performed by repeated testing of the cars over a two and one-half
year period. This report summarizes analyses of the data base, and includes results
on idle CO levels, mass emissions of HC, CO, NO , sulfate, S02 and total particulate;
total particulate elemental analyses, catalyst activity, and fuel economy. Test cycles
used were the 1975 FTP, one-hour 50 mph cruise, Congested Freeway Driving Schedule,
Highway Fuel Economy Test, and idle,30 and 50 mph cruise for catalyst activity tests.
Fuel economy data for over-the-road driving are also presented from on-board totalizing
fuel and engine hour meters on each car.
Idle CO Indicative of maladjusted carburetors (> 1*) was found to correlate with
FTP CO emissions, purge of stored sulfur in the form of S02 from catalysts, anc
decreases in catalyst activity at idle in comparison to 30 and 50 mph activity results
Particulate sulfur emissions accounted for only 3.7% of fuel sulfur for the 256 CFDS
tests in the data base. Over-the-road fuel economy was most closely represented by
the FTP (city) value.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
18. DISTRIBUTION STATEMENT
DISTRIBUTE TO PUBLIC
19. SECURITY CLASS /Titit Keporlj
UNCLASSIFIED
21. NO. Of PAGES
120
20 SECURITY CLASS /This pagt)
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (Rev. 4-77) PREV.OUS EDIT.ON is OBSOLETE
108
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