real-world emissions from heavy haulers in alberta oil sands … · 2018. 3. 4. · cat797b-1...
TRANSCRIPT
Real-World Emissions from Heavy
Haulers in Alberta Oil Sands Mining
John G. Watson1 ([email protected]) Judith Chow1, Xiaoliang Wang1, Steven D. Kohl1, Barbara
Zielinska1, Allan H. Legge2, and Kevin E. Percy3
1Desert Research Institute, Reno, NV, U.S.A. 2Biosphere Solutions, Calgary, Canada
3Wood Buffalo Environmental Association, Ft. McMurray, Canada
Presented at
North American Oil and Gas Conference
Calgary, AB, Canada
October 22, 2014
Study Objectives
• Integrate modern measurement systems to quantify multipollutant emissions with multiple effects
• Measure real-world emission factors for gaseous and particulate emittants
• Obtain VOC and PM2.5 source profiles for emission inventory development and source apportionment
What do we mean by “multipollutant” and “multiple effect”? Future air quality management will address more than criteria
contaminants
Chow, J.C.; Watson, J.G. (2011). Air quality management of multiple pollutants and multiple
effects. Air Quality and Climate Change Journal, 45(3):26-32.
https://www.researchgate.net/publication/234903062_Air_quality_management_of_multiple_pollu
tants_and_multiple_effects?ev=prf_pub.
-25
25
75
125
175
225
275
325
375
1 2 3 4 5 6 7 8 9 10
Decile
Em
issio
n F
acto
r [g
CO/k
gF
ue
l]
CO
PM
0.025
0.275
0.225
0.175
0.125
0.075
0.375
0.325
-0.025
Em
issio
n F
acto
r [g
PM
/kg
Fu
el]
-1%
3%
0%
4%
0%
2%
1%
3%
1%
2%
2%
7%
3%
12%
5%
14%
12%
18%
78%
35%
Mazzoleni et al., 2004, JAWMA, 54(6):711-726
What do we man by real-world emissions?
Average emission rates measured in the laboratory for engine certification
don’t represent the full range of equipment, fuels, and operating conditions
Engine certification tests are performed on engine
dynamometers independent of the application Sample ISO 8178 Non-Road Steady-State Test Cycle Weighing Factors
Mode Number
1 2 3 4 5 6 7 8
Torque, %
100 75 50 10 100 75 50 0
Speed Rated speed Intermediate speed Low idle
Type C1* Factors
0.15 0.15 0.15 0.10 0.10 0.10 0.10 0.15
• Engines behave differently within and outside of the vehicle
• Engines are not subject to same aging and maintenance conditions
• Fuels are different
• Operating cycles differ, especially for transient operations
Diesel engines are the world’s workhorses • Advantages:
– High fuel efficiency (40-50% as compared to 25-35% for gasoline engines), more powerful, and more durable due to:
Higher compression ratio
Fuel-lean combustion
No throttling loss
• Disadvantages:
– Heavier and more expensive
– Emit more NOx and PM
– Noisier and harder to start in cold weather than gasoline engines
Ideal for off-road applications!
Rudolf Diesel (1858‒1913)
Four-stroke Diesel Cycle: • Air intake • Compression • Fuel injection • Exhaust
http://auto.howstuffworks.com/diesel1.htm#
The AOSR heavy hauler fleet operates all the
time and is growing rapidly
• Several hundred heavy haulers operate in the AOSR
• Each truck operates >6000 hr/yr and consumes > 1 million L/yr of diesel fuel
• Surface mining operations account for >75% of diesel fuel consumption
M.J. Bradley & Associates (2008)
Caterpillar 797B heavy haulers constitute most of the
fleet
Parameter CAT 797B
Introduction to Service 2002
Nominal Payload Capacity 345 tonnes
Gross Operating Weight 624 tonnes
Engine Power 3,370 hp (2,513 kW)
Displacement 117.1 Liter
Top Speed (Loaded) 42 mph (68 km/h)
Fuel Capacity 1,800 US gal (6,814 Liter)
Emission Standards Tier 1
Four Caterpillar 797B heavy haulers
were tested in three oil sands facilities
Trucks CAT
797B-1 CAT
797B-2 CAT
797B-3 CAT
797B-4
Facility B A A C
Study year 2009 2009 2010 2010
# of trucks in the fleet
60 41 41 23
Continuous and integrated samples of ~300
separate pollutants were measured
Residence time is ~3 sec
3 – 35 times dilution ratio
Muffler
Elbow
Connector
Engine
Exhaust
ThermocoupleOmega TJ36-CASS-116U-6-SB
For Exhaust T URG-2000-30ENG
Cyclone
7.1 µm Cut
0.8 L/min
Residence
Chamber
PM2.5
impactor
Teflon + Citric acid
(mass, babs, element,
isotope, NH3)
Pump
Quartz + K2CO3
(Ions, WSOC, carbohydrates,
organic acids, HULIS, SO2)
Quartz + AgNO3
(EC/OC, markers, H2S)
Nuclepore
(Lichen study)
5 L
/min
5 L
/min
5 L
/min
5 L
/min
Filter
sampler
Flow
meter
TSI DustTrak DRX
(PM1, PM2.5, PM4,
PM10, PM15)
3 L
/min
0.0
5 L
/min
Magee AE51
(BC)
0.7
L/m
in
TSI CPC 3007
(Concentration 0.01-2.5 µm)
PP
Sy
ste
ms
CO
2 s
en
so
rs
Testo 350
(CO, CO2, NO, NO2,
SO2, O2,T, P)
PID 102+
(Total
VOCs)
0.1
6 L
/min
1 L
/min
0.0
1 L
/min
Module 2:
Continuous Gas
Monitoring
Teflon
Filter
1 liter
Canister
(CH4, C2-C12)
1 L
/min
Dilu
ted
1 L
/min
Un
dilu
ted
1 L
/min
Ba
ck
gro
un
d
DryerHEPA
HEPA
Filter
Activated
CharcoalAir
CompressorValve
32 L/min
5.8
8 L
/min
Makeup Flow
For Balance
Flowmeter
3.75 L/min25.88 L/min
3.17 L/min
32.8 L/min
Dilutor
Module 1: Sample
Conditioning
Heavy HaulerExhaust Pipe
CaCl2 Desiccant
Valves
Pump
1 L
/min
Valve
Pump
DNPH
(Carbonyls)
Insulated
Transfer
Line
Water
Trap
Module 3:
Integrated
Sampling
Module 4:
Continuous PM
Monitoring
Module 5:
Power Supply
Valve
Filter
Measurement systems are located in interconnected modules
Testo 350CO2
SensorsPID Analyzer
Filter PacksCanisterPump for
Makeup FlowFlowmeters
Pumps
CPC DRX OPCComputer Deep Cycle
Marine BatteryVoltage
Regulator
Battery Monitor
Sample Conditioning Module Continuous Gas Module
Integrated Sample Module Continuous PM Module Power Supply
Each module measures = 80 cm L × 52 cm W × 32 cm H; Modules 1-4 weighs ~25 kg each, and power supply module with two battery weighs 80 kg.
Sample
Introduction
Elutriator Dilution
Air/Sample Mixer
Residence
ChamberDilution Air
Introduction
Air Compressor Valve Flowmeter Carbon Filter
HEPA
Filter
Stream for
Undiluted
CO2
Dryer Teflon
Filter
Cyclone
Stream to
Module 2
Stream to
Module 3
Stream to
Module 4
Stream to
Background
CO2
Samples were drawn from the exhaust pipe (muffler
outlet) of CAT 797B and diluted to ambient
temperatures
Driver
cabin
Sampling
platform
Sampling
modules
Muffler
Flange connecting
to the body
Exhaust pipe
Sampling port
Thermocouple
Sample
transfer line
Samples were taken during real-world
complete operating cycles
Loading Traveling with load
Dumping Traveling without load
EFP: Emission factor in g pollutant per g fuel CMFfuel: Carbon mass fraction of the fuel (86.2% for diesel) CP: Concentration of pollutant P in g/m3 CCO2: Concentrations of CO2 in g/m3 CCO: Concentrations of CO in g/m3
MC: Atomic weight of carbon (12 g/mole) MCO2: Molecular weight CO2 (44 g/mole) MCO: Molecular weight CO (28 g/mole) This equation assumes all carbon in fuel is converted to CO2 and CO.
Fuel-based Emission Factors (EF) are determined
CO
CCO
CO
CCO
PfuelP
M
MC
M
MC
CCMFEF
2
2
Moosmüller et al. (2003)
Differences between CAT 797B trucks are within experimental
variations (Higher emissions for CO, NOx, and particle number at Facility C)
9.6
0.7
49.3
0.50.5 0.5x1015
6.5
1.0
52.4
0.8
0.5
5.4
10.7
0.2
50.3
0.6
0.9
2.9
14.3
0.6
70.0
0.9
10.1
0.1
1
10
100
1000
Emis
sio
n F
cto
r (g
/kg
fue
l)
Pollutant
CAT797B-1 (Facility B) CAT797B-2 (Facility A)
CAT797B-3 (Facility A) CAT797B-4 (Facility C)
NMHC NOxCO BlackCarbon
PM2.5Particle
Number
NOx is expressed as NO2
Real-world operations emitted higher CO and NOx, lower
NMHC, and comparable PM2.5 to certification tests
• Real-world/Certification Ratio
– CO: 111-243%
– NMHC: 12-66%
– NOx: 131-187%
– PM2.5:65-112% Note: NOx is expressed as NO2
Emittant
Em
issio
n F
acto
r (g
/kg
fu
el)
0.1
1
10
100CAT 797B-1
CAT 797B-2
CAT 797B-3
CAT 797B-4
Certification
CO NMHC NOx PM
2.5
CAT 797B-3 (with fuel additive) reported 60–85% higher CO and BC,
70% lower NMHC, similar NOx, 27–56% less PM2.5 and particle
number than CAT 797B-2 (no additive)
The fuel additive does not have significant impact on emissions in Facility A. The two trucks tested one year apart (CAT 797B-2 in 2009 and CAT 797B-3 in 2010) reported comparable emissions.
6.5
1.0
52.4
0.8
0.5
5.4x1015 (#/kg fuel)10.7
0.2
50.3
0.6
0.9
2.9x1015
0.1
1
10
100
1000Em
issi
on
Fct
or
(g/k
g fu
el)
Pollutant
CAT797B-2 (Facility A, w/o Fuel Aditive)
CAT797B-3 (Facility A, w/ fuel additive)
NMHC NOxCO Black
CarbonPM2.5
Particle
Number
Different methods used to estimate emissions for the NPRI give different
results Method 1: Emission Rate = EF (g/kg fuel) × Fuel consumption (Facility A)
• Used 1985 EPA AP-42 EFs
Method 2: Emission = EFTier1 (g/kWh) × Operating Hr × Rated Vehicle Power × Load Factor (Facility A)
• Load factor is taken conservatively (59% or 100% recommended by EPA; CAT estimated 20‒50%; one facility estimated 35‒48%)
Method 3: Emission = max(EFTier1, EFcert composite) ×1.1/BSFC × Fuel consumption (Facility B)
BSFC = brake-specific fuel consumption (kg fuel/kWh)
0
20
40
60
80
100
120
140
CO NMHC NOx PM
Em
iss
ion
s (
ton
ne
s/t
ruck
/yr)
Emittant
Method 1
Method 2
Method 3
Real-World
Emissions varied by operating conditions (time series)
i. Idling: Concentration stable
and low.
ii. Leaving parking lot: All
concentrations increase.
iii. Top of uphill: Spikes of
concentrations.
iv.Leaving with load: high
concentration spikes when
accelerating.
v. Leaving after dumping:
concentration spikes when
climbing uphill.
vi.Waiting for load: low
concentration except when
moving forward in line.
Ground Speed(mph)
0
10
20
CO2
(ppm)
0
20000
40000
60000
80000
CO(ppm)
010002000300040005000
NOx
(ppm)
0
2000
4000
Black CarbonConcentration
(mg/m3)
0
20
40
60
80
NumberConcentration
(cm-3
)
01e+82e+83e+84e+85e+86e+8
PM2.5
Concentration
(mg/m3)
0
1e+2
2e+2
Total VOCs(ppm)
0100200300400500600
EngineSpeed(rpm)
600
900
1200
1500
Time (hh:mm)
12:35 12:40 12:45 12:50 12:55 13:00 13:05 13:10 13:15 13:20
Elevation(m)
240
260
280
300
i. Idle ii. Leaving
parking lot iv. Leaving
with load
v. Leaving
after dumping
Leaving
with load
iii. Top of
uphill road
vi. Waiting
for load
(c) CO2 analyzer
(b) Emission analyzer
(d) Emission analyzer
(a) PID analyzer
(f) micro-aethalometer
(e) CPC
(i) GPS
(h) Truck
(j) GPS
(g) DustTrak DRX
Traveling with load has the highest emission rates
0.0
0.5
1.0
1.5
2.0
2.5
Idle Traveling w/ load Traveling w/o
load
VO
Cs
Em
iss
ion
(g
/s)
Truck Operation
Total VOCs
0
1
2
3
4
5
6
7
Idle Traveling w/ load Traveling w/o load
CO
Em
iss
ion
(g
/s)
Truck Operation
CO
0
2
4
6
8
10
12
Idle Traveling w/ load Traveling w/o load
NO
Em
iss
ion
(g
/s)
Truck Operation
NO
0
0.04
0.08
0.12
0.16
Idle Traveling w/ load Traveling w/o load
PM
2.5
Em
iss
ion
(g
/s)
Truck Operation
PM2.5
NMHCs consist mostly of alkenes and alkanes (~10-80%).
Abundance is normalized to the sum of 56 photochemical assessment monitoring station (PAMS) compounds
Compound % of PAMS
Ethylene 28.3%
Propylene 15.4%
n-Heptane 5.6%
Acetylene 5.4%
1-Butene 4.9%
n-Decane 4.5%
Isobutane 4.1%
Isopentane 3.7%
Toluene 3.6%
Ethane 3.6%
Benzene 3.4%
Isobutylene 2.9%
n-Nonane 1.9%
2-Methyl-1-Pentene 1.8%
1-Pentene 1.7%
n-Octane 1.4%
n-Butane 1.3%
1-Heptene 1.3%
Propane 1.3%
m/p-Xylene 1.3%
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Alkanes andCylcoalkanes
Alkenes Alkyne Aromatics
Ab
un
dan
ce N
orm
aliz
ed
to
Su
m o
f PA
MS
NMHC Group
CAT 797B-1
CAT 797B-2
CAT 797B-3
CAT 797B-4
EC and OC are the most abundant (~68 - 88%) components in PM2.5
source profiles; Elevated P, S, Ca, and Zn suggest the origin from lube oil.
NO2-
NO3-
PO4≡
SO4=
NH4+
Na+
Mg++
Ca++
OCEC
Al
SiP
S
Cl
K
Ca
Sc
Ti
Fe
Cu
Zn
Ga
Sr
Zr
Nb
Mo
Ag
Sn
Sb Ba
La
Ce
Sm
Eu
Ir
Au PbUr
0.001
0.01
0.1
1
10
100
Ch
em
ica
l Ab
un
da
nc
e (
%)
Chemical Species
CAT 797B-1
Ch
em
ical A
bu
nd
an
ce (
%)
OC21%
EC56%
Elements2%
Soluble ions8%
Unidentified13%
CAT 797B-4
OC21%
EC67%
Elements1%
Soluble ions2%
Unidentified9%
CAT 797B-1
OC36%
EC49%
Elements2%
Soluble ions4%
Unidentified9%
CAT 797B-2
OC14%
EC55%
Elements1%
Soluble ions3%
Unidentified27%
CAT 797B-3
Particle-bound PAHs show two distinct
abundance groups
0.00
0.02
0.04
0.06
ph
en
an
thre
ne
an
thra
ce
ne
flu
ora
nth
en
e
pyre
ne
ben
zo
[a]a
nth
race
ne
ch
rys
en
e+
tri
ph
en
yle
ne
ben
zo
[b]f
luo
ran
then
e
ben
zo
[j+
k]f
luo
ran
then
e
ben
zo
[a]f
luo
ran
then
e
ben
zo
[e]p
yre
ne
ben
zo
[a]p
yre
ne
pery
len
e
ind
en
o[1
,2,3
-cd
]pyre
ne
dib
en
zo
[a,h
]an
thra
cen
e
ben
zo
[gh
i]p
ery
len
e
co
ron
en
e
dib
en
zo
[a,e
]py
ren
e
9-f
luo
ren
on
e
dib
en
zo
thio
ph
en
e
1 m
eth
yl p
he
na
nth
ren
e
2 m
eth
yl p
hen
an
thre
ne
3,6
dim
eth
yl p
he
na
nth
ren
e
me
thylf
luo
ran
then
e
rete
ne
ben
zo
(gh
i)fl
uo
ran
the
ne
ben
zo
(c)p
hen
an
thre
ne
benzo(b)naphtho[1,2-…
cyclo
pen
ta[c
d]p
yre
ne
Ma
ss
Pe
rce
nta
ge o
f O
rga
nic
Carb
on
(%
)
PAHs
CAT 797B-1
CAT 797B-2
CAT 797B-3
CAT 797B-4
Particle-bound n-Alkanes show abundances
between C19 and C30
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
n-p
en
tad
eca
ne
(n
-C15
)
n-h
exa
de
ca
ne
(n
-C1
6)
n-h
ep
tad
ecan
e (
n-C
17)
n-o
cta
de
ca
ne
(n
-C18
)
n-n
on
ad
eca
ne
(n
-C1
9)
n-i
co
san
e (
n-C
20)
n-h
en
eic
os
an
e (
n-C
21
)
n-d
oco
sa
ne
(n
-C2
2)
n-t
ric
os
an
e (
n-C
23
)
n-t
etr
aco
sa
ne
(n
-C24
)
n-p
en
taco
sa
ne
(n
-C25
)
n-h
exa
co
sa
ne
(n
-C2
6)
n-h
ep
taco
sa
ne
(n
-C27
)
n-o
cta
co
sa
ne
(n
-C28
)
n-n
on
aco
sa
ne
(n
-C2
9)
n-t
ria
co
nta
ne
(n
-C30
)
n-h
en
tria
co
tan
e (
n-C
31
)
n-d
otr
iaco
nta
ne
(n
-C3
2)
n-t
ritr
iac
tota
ne
(n
-C3
3)
n-t
etr
atr
iacto
an
e (
n-C
34)
n-p
en
tatr
iaco
nta
ne
(n
-C35
)
n-h
exa
tria
co
nta
ne
(n
-C36
)
n-h
ep
tatr
iaco
nta
ne
(n
-C37
)
n-o
cta
tria
co
nta
ne
(n
-C38
)
n-n
on
atr
iaco
nta
ne
(n
-C3
9)
n-t
etr
aco
nta
ne
(n
-C4
0)
**
Ma
ss
Pe
rce
nta
ge o
f O
rga
nic
Carb
on
(%
)
n-Alkanes
CAT 797B-1
CAT 797B-2
CAT 797B-3
CAT 797B-4
Summary • Real-world emissions were characterized for
four CAT 797Bs under normal operations.
• Real-world operations emitted higher CO and NOx, lower NMHC, and comparable PM2.5 to certification tests.
• Emission estimation methods differ by facility and from the real-world measurements
• Truck emission source profiles showed 10 – 80% alkenes and alkanes in non-methane hydrocarbons, and 68 – 88% carbon (OC and EC) in PM2.5.
How to use this information
• Criteria Contaminants
– Develop a more accurate and consistent estimate of fleet emissions, based on distributions of load factors and fuel consumption available from tracking systems
• Greenhouse Gases
– Estimate mine fleet Global Warming Potentials (GWP) for life-cycle assessments
• Toxics Inventory
– Revise emission estimates
• Source Apportionment
– Use chemical profiles to identify contributions to adverse ecosystem responses
• Anticipate future emission requirements
– Ultrafine particles and black carbon (EU and California are moving in this direction)
Future engines will substantially reduce emissions as
they penetrate the fleet
http://www.tandfonline.com/doi/pdf/10.1080/10473289.2001.10464315
http://www.tandfonline.com/doi/pdf/10.1080/10473289.2011.599277
0.1
1
10
100
Em
iss
ion
Fa
cto
r (g
/kg
fu
el)
Truck Tiers (Model Year)
CO NMHC
NOx PM
Base(<1988)
T0(1988-2000)
T1(2000-2006)
T2(2006-2011)
T4(2011-2015)
797B
/T282B
http://www.awma.org/publications/
journal
Acknowledgements
• Sponsor: Wood Buffalo Environmental Association (WBEA, Ft. McMurray, Alberta). The content and opinions expressed by the authors in this presentation do not necessarily reflect the views of WBEA or of the WBEA membership
• Special appreciation to: Drs. Ken Foster and Yu-Mei Hsu, Ms. Carna MacEachern, Ms. Veronica Chisholm, and environmental officers and staffs at each facility