On-board Emission Measurement from the World`s Largest Heavy

On-board Emission Measurement from
the World’s Largest Heavy Haulers
Xiaoliang Wang ([email protected])
Judith C. Chow
John G. Watson
Steven D. Kohl
Steven Gronstal
Desert Research Institute
Nevada System of Higher Education
Reno, NV, U.S.A.
Presented at
A&WMA International Specialty Conference: Leapfrogging
Opportunities for Air Quality Improvement
May 13, 2010
Background: Athabasca Oil Sands Region (AOSR)
Reserve: 1.7 trillion barrels of bitumen
Production: 1.3 million barrels per day in 2008
Wikipedia: “Athabasca Oil Sands”
Example of Emissions from One AOSR Facility
Mine fleet is a major contributor to CO, NOx, and PM in oil sand operations
Emission in tons (2003)
CO
H2S
NOx
TPM
PM10
PM2.5
SO2
VOC
3466
0
99
396
313
178
10
446
Flaring
216
5
40
1
1
1
2015
50
Fuel combustion-Cogeneration
574
0
1296
13
13
13
42
19
Fuel combustion-Gasoline light
vehicle fleet
203
0
271
17
17
16
2
350
7688
0
9037
213
205
192
12
317
23990
0
10289
2582
1540
524
76104
151
0
18
0
0
0
0
0
32859
138
6
0
22
13
4
0
7
36276
30
21033
3245
2102
929
78185
34199
21%
0%
43%
7%
10%
21%
0%
1%
Sources
Biomass combustion
Fuel combustion-Mine mobile fleet
Fuel combustion-Process
Fugitive
Process venting
All
Mine fleet%
Source: Clearstone Engineering Ltd. Report (2006).
Compliance testing do not represent real-world emissions
• To be in compliance with emission standards
requires compliance emission rates.
• Source-oriented dispersion modeling and
Receptor-oriented source apportionment modeling
require real-world emission rates.
• Forest and health effects studies require real-world
emission rates and source profiles.
Real-world emissions are needed for all but certification and compliance!
Objectives
•
•
•
Design and test an on-board system that
measures engine emissions under real-world
operations.
Measure real-wold emission factors of criteria
and non-criteria air pollutants.
Obtain VOC and PM2.5 source profiles.
Vehicle: Caterpillar 797B Heavy Hauler
Parameter
Specification
Introduction to Service
2002
Nominal Payload Capacity
345 tons
Gross Operating Weight
624 tons
Engine Power
3,370 hp (2,513 kW)
Displacement
117.1 L
Top Speed (Loaded)
42 mph (68 km/h)
Fuel Capacity
1,800 US gal (6,814 liter)
CAT 797 series
are among the
world’s largest
heavy haulers.
Schematics of the On-board Emission Measurement System
Exhaust Pipe
CAT 797B Hauler
w or
bo ct
El ne
on
C
Engine
Exhaust
Muffler
Box1: Sample
Conditioning
Box5: Battery
HEPA
Air
Compressor
HEPA
Filter
Dryer
0.8 L/min
Activated
Charcoal
Valve
Dilutor
Residence
Chamber
Flowmeter
32 L/min
Thermocouple
Omega TJ36-CASS-116U-6-SB
For Exhaust T
URG-2000-30ENG
Cyclone
7.1 µm Cut
33.12 L/min
PID 102+
(VOC)
Box 2: Real Time
Gas Module
Filter
sampler
Makeup Flow
For Balance
Nuclepore
Teflon + Citric acid
(mass, babs, element, (Lichen study)
isotope, NH3)
Quartz + AgNO3
1 liter
(EC/OC, markers, H2S)
Canister
(CH4, C2-C12)
Quartz + K2CO3
(Ions, WSOC, carbohydrates,
organic acids, HULIS, SO2)
Box 3: Integrated
Sample Module
TSI DustTrak DRX
(PM1, PM2.5, PM4,
PM10, PM15)
1.2 L/min
0.05 L/min
0.7 L/min
3 L/min
5 L/min
5 L/min
6.0 L/min
0.01 L/min
1 L/min
PM2.5
impactor
Pump
Testo 350
(CO, CO2, NO, NO2,
SO2, O2,T, P)
4.95 L/min
26 L/min
Flow
meter
Diluted
1 L/min
0.16 L/min
1 L/min
Background
PP Systems CO2 sensors
Undiluted
1 L/min
5 L/min
2.17 L/min
5 L/min
Filter
Grimm 1.108 OPC
(Size distribution
0.3-25 µm)
Magee AE51
(BC)
TSI CPC 3007
(Concentration 0.01-1 µm)
Box 4: Real Time
PM Module
On-board Emission Measurement System
Carbon
Filter
Air
Compressor
Stream to
Background
CO2
Valve Flowmeter
HEPA
Filter
Dryer
Stream to
Box 2
Teflon
Filter
Stream to
Box 3
Stream to
Box 4
Residence
Chamber Cyclone
Sample
Dilutor Dilution Air
Introduction Introduction
Stream for
Undiluted
CO2
CO2
Sensors
Testo 350
PID Analyzer
Battery Monitor
Pumps
Pump for
Makeup Flow
Computer
Flowmeters
Canister
Filter Packs
CPC
DRX
OPC
Deep Cycle
Marine Battery
Voltage
Regulator
Example of Time Series of Emission Concentrations
100
2000
1500
80
1000
70
500
60000
CO2
(ppm)
40000
NO (ppm)
Engine Speed
(rpm)
60
50
40
30
20000
20
0
10
600
CO
(ppm)
y = 0.0092x + 6.89
R2 = 0.65
90
0
0
400
2000
200
4000
CO2 (ppm)
6000
8000
0
NO
(ppm)
60
NO2
(ppm)
40
120
y = 16.04x + 2.83
R2 = 0.60
80
CO (ppm)
1000
800
600
400
200
0
40
20
0
4e+7
3e+7
2e+7
1e+7
0
Number
Concentration
(cm-3)
40
-1
0
1
2
Black carbon (mg/m 3)
3
4
3
4
14
y = 1.97x + 0.11
R2 = 0.57
12
20
10
0
40
30
20
10
0
PM2.5 Concentration
(mg/m3)
PM2.5 (mg/m 3)
Black Carbon
Concentration
(mg/m3)
0
8
6
4
2
0
Idle Leaving
parking lot
Waiting
to load
Leaving
with load
Backing
to shovel
Dumping
oil sand
Waiting
to load
Leaving
with load
Backing
to shovel
-2
-1
0
1
2
Black carbon (mg/m 3)
Sub-activity Engine Conditions and Emission Factors
1800
600
90
1200
900
600
500
Exhaust T (C)
1500
60
30
300
Load to dump
200
0
Dump to load
Idle
Truck Operation
Load to dump
Dump to load
30
15
10
5
NO2 Emission (g/kg fuel)
20
NO
40
20
0
0
Load to dump
Dump to load
Idle
Truck Operation
8.0E+14
4.0E+14
0.0E+00
Truck Operation
10
5
0
Idle
Dump to load
Load to dump
Dump to load
Truck Operation
PM2.5 Emission (g/kg fuel)
BC Emission (g/kg fuel)
1.2E+15
Load to dump
NO2
Dump to load
1.5
Particle number
Dump to load
15
Truck Operation
1.6E+15
Idle
Load to dump
Load to dump
Truck Operation
60
CO
Idle
Idle
Truck Operation
NO Emission (g/kg fuel)
CO Emission (g/kg fuel)
300
0
Idle
25
400
100
0
Number Emission (#/kg fuel)
Exhaust temperature
Engine load
Engine Load (%)
Engine Speed (rpm)
Engine speed
BC
1.2
0.9
0.6
0.3
0
1.5
1.2
PM2.5 (DRX)
0.9
0.6
0.3
0
Idle
Load to dump
Truck Operation
Dump to load
Idle
Load to dump
Truck Operation
Dump to load
Comparison of CAT 797B to EPA Tier 1
Standards
Emission Factor
(g/kg fuel)
Species
Gases
PM
CO2
3147
CH4
1.6
0.6
CO
8.5
3.8
NO
31.0
NO2
NOx
EPA Tier 1
(g/kg fuel)
6
Emission Rate
(kg/day)
14767
28
Emission Rate
(ton/year)
5390
10
7.6
2.6
2.8
0.9
39.7
17.6
14.5
6.4
5.1
145.5
23.7
53.1
8.7
3.6
1.2
16.8
5.5
6.1
2.0
34.6
6.0
162.3
28.3
59.2
10.3
51.0
41.2
SO2
(5.3
6.3)×10-3
(2.5
2.9) ×10-2
(9.2
1.1) ×10-2
H2S
(4.3
6.4) ×10-5
(2.0
3.0) ×10-4
(7.4
1.1) ×10-4
NH3
(7.2
15) ×10-5
(3.4
7.1) ×10-4
(1.2
2.6) ×10-4
NMHC
(8.7
3.1) ×10-2
Number
(2.4
3.0) ×1015
PM2.5
0.62
0.26
BC
0.49
0.11
5.8
0.41
0.14
(1.1 1.4) ×1019
2.4
Assumed: Fuel consumption rate 5520 L/day;
Brake specific fuel consumption (BSFC) 0.223 kg/kW-hr or 0.367 lb/hp-hr.
0.15
0.05
(4.0 5.2) ×1021
2.92
1.24
1.07
0.45
2.32
0.51
0.85
0.19
Concentration Normalized to Sum of PAMS
Alkanes and alkenes ~30-60%,
and aromatics ~10% of NMHC
0.255
0.046
n-Heptane
0.111
0.128
Propylene
0.100
0.022
Acetylene
0.058
0.022
Site S
1-Butene
0.057
0.026
Site A
Ethane
0.046
0.037
Toluene
0.036
0.010
n-Decane
0.032
0.018
1-Pentene
0.022
0.007
n-Nonane
0.021
0.016
n-Butane
0.018
0.014
isobutylene
0.017
0.004
Benzene
0.017
0.008
2-Methyl-1-Pentene
0.016
0.006
n-Undecane
0.014
0.005
m/p-Xylene
0.014
0.005
n-Hexane
0.014
0.006
Propane
0.012
0.009
m-Ethyltoluene
0.012
0.006
n-Pentane
0.012
0.005
1-heptene
0.010
0.004
0.5
0.4
0.3
0.2
0.1
0.0
Alkanes
&cycloalkanes
Alkenes
Acetylene
NMHC Compound Group
Abundance is normalized to the sum of 55
photochemical assessment monitoring station
(PAMS) compounds
Abundance
Ethylene
0.7
0.6
Compound
Aromatics
Highlighted are the EPA mobile source air toxics (MSATs).
Unidentified
9%
Soluble ions
3%
Carbonaceous species
account for ~87% of PM2.5
OC
27%
Elements
1%
EC
60%
100
Site A
OC
EC
Chemical Abundance (%)
10
3-
PO4
NO3
1
2+
2-
SO4
Mg
+
NH4
Ca2+
Si
Zn
Ca
P
Cl
S
-
0.1
NO2
Mo
La
Fe Cu
Na+
0.01
Sb
K+
K
Sm
Eu
Ur
Ga
Sc
Ba
Sr
Ti
0.001
Chemical Species
Zr Nb
Ag Sn
Au
Summary
• An on-board system was designed and deployed to
measure emissions from CAT 797B mining trucks
under real-world operations.
• CAT 797B Emission factors were below the EPA Tier
1 standards for CO, NOx, NMHC and PM.
• Source profiles found abundant alkanes and alkenes
in NMHC, and OC and EC in PM2.5.
Acknowledgements
• Sponsor: Wood Buffalo Environmental
Association (WBEA).
• Valuable discussions and field testing
coordination: Dr. Allan Legge (including project
initiation), Drs. Kevin Percy, and Yu-Mei Hsu,
Ms. Carna MacEachern, Ms. Simone Balaski,
and environmental officers at each company.
Filter packs
PM2.5 Impactor
Channel 1
(5 L/min)
Teflon-membrane
filter
Mass,
light transmission,
rare-earth elements,
elements, isotopes
PM2.5 Impactor
Channel 2
(5 L/min)
Quartz-fiber filter
Ions (Cl-,NO2-, NO3-,
PO4=, SO4=, NH4+,
Na+, Mg++, K+, Ca++),
total WSOC,
WSOC classesa,
Carbohydrates,
organic acids,
HULIS
Citric acidimpregnated
cellulose-fiber filter
Potassium
carbonateimpregnated
cellulose-fiber filter
NH3 as NH4+
SO2 as SO4=
PM2.5 Impactor
PM2.5 Impactor
Channel 3
Channel 4
(5 L/min)
Nuclepore
Polycarbonate filter
Quartz-fiber filter
OC, EC, carbon
fractions, carbonate,
~130 alkanes, alkenes,
PAHs, hopanes, and
steranes
Silver nitrateimpregnated
cellulose-fiber filter
H2S as S
(5 L/min)
Lichen study mass and
elemental analysis or
morphological analysis
a
Neutral compounds (NC)
Mono/dicarboxylic acids (MDA)
Polycarboxylic acids (PA)
Filter Analysis
Chemical
Analysisa
Teflonmembrane
filter
Quartz-fiber
filter
XRF for 51
elementsb
½ filter
extracted in
20 ml
distilleddeionized
water (DDW)
Acid
Digestion
Quartz-fiber
filter
0.5 cm2
punch
OC, EC, carbon
fractions,
carbonate by
thermal/optical
carbon
~1-2
cm2
punch
Organic
Markers by
TD-GC/MSc
Citric acidimpregnated
cellulose-fiber
filter
K2CO3impregnated
cellulose-fiber
filter
Silver nitrateimpregnated
cellulose-fiber
filter
Nuclepore
polycarbonate
-membrane
filter
½ filter
extracted in
10 ml DDW
½ filter
extracted in
10 ml 1:11
hydrogen
peroxide:
DDW dilution
Whole filter
without
extraction
Elemental
analysis or
morphological
analysis for
lichen studies
Ammonia by
AC
Sulfur dioxide by
IC
ICP-MS for
rare-earth
elements and
isotopesd
b
c
d
10 ml for anions and
cationse by IC, AC, and
AAS, acidified to pH 2 with
HCl
1 ml for total
WSOC by
thermal/optical
carbon
1 ml speciated WSOC
separated into three
classes: NC, MDA, and
PA by HPLC-IEC and
UV/Vis detection at
254 nm
Filtration of 5 ml through 0.2 µm
PTFE syringe filter
1 ml for NC
speciation (e.g.,
carbohydrates) by
IC-PAD
1 ml for MDA
speciation (e.g.,
organic acids) by IC
with conductivity
detector
e
Hydrogen
sulfide by
XRF as sulfur
Al – U (see Table 7-1)
124 organic marker species (see
Table 7-1)
Cs, Ba, La, Ce, Pr, Nd, Sm, Eu,
Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu,
Pb204, 205, 206, 207, 208
Cl-, NO2, NO3-, PO4=, SO4= (by
IC); NH4+ (by AC); Na+, Mg++, K+,
and Ca++ (by AAS)
1 ml for PA
speciation (e.g.,
HULIS) by HPLC–
SEC–ELSD–UV/VIS
a
Analytical Instruments:
AAS: Atomic absorption spectroscopy
AC: Automated colorimetry
ELSD: Evaporative light scattering
detector
HPLC-IEC: High performance liquid
chromatography with an ion exchange
column
IC: Ion chromatography
IC-PAD: IC with pulsed amperometric
detector
ICP-MS: Inductively coupled plasma –
mass spectrometry
PTFE: Polytetrafluoroethylene
SEC: Size-exclusion chromatography
TD-GC/MS: Thermal desorption-gas
chromatography/mass spectrometry
UV/VIS: Ultraviolet detector
XRF: X-ray fluorescence
Observables
OC: Organic carbon
EC: Elemental carbon
HULIS: Humic-like substances
MDA: Mono/dicarboxylic acids
NC: Neutral/basic compounds
PA: Polycarboxylic acids
BC, EC, babs
900
14000
babs
BC
800
700
BC = 1.39 x EC - 62
babs (mM-1)
10000
600
R2 = 0.96
8000
500
6000
400
300
4000
200
babs = 15.9 x EC - 1400
2000
100
R2 = 0.83
0
0
100
200
300
400
500
600
EC Concentration (µg/m3)
700
800
900
0
1000
BC Concentration (µg/m3)
12000