PM , Air Toxics, And Crankcase Emissions In The Truck Stop … · 2015-08-28 · Managed by...

Managed by UT-Battellefor the Department of Energy

PM2.5 , Air Toxics, And Crankcase Emissions In The Truck Stop Environment

November 5, 2009

National Ambient Air Monitoring Conference

Nashville, Tennessee

John Storey, Jim Parks, and Teresa Barone

Fuels, Engines, and Emissions Research Center

[email protected] 865-946-1232

2 Managed by UT-Battellefor the Department of Energy Presentation_name

Acknowledgements

This work supported by the NTRC, Inc. with CMAQ funds ultimately from FHWA

Collaboration with UT –

Dr. Terry Miller et al.

Dr. James Eberhardt and DOE’s

Office of Freedom CAR and Vehicle Technologies’

Environmental

Sciences Program provided support for the WRELI initiative

EPA Office of Transportation and Air Quality provided some support for the crankcase emissions study


Average Annual Daily Truck TrafficSource: Federal Highway Administration (DOT) [www.dot.gov/freight/]


Average Annual Daily Truck Traffic … Expected to GrowSource: Federal Highway Administration (DOT) [www.dot.gov/freight/]


Tennessee Truck Traffic

1998 2020AADTT: Average Annual Daily Truck Traffic

50,00025,00012,500


Aerial view looking South

Region in non-attainment for PM2.5 , near non-attainment for ozone


Why study the Watt Road interchange?

Confluence of I-40 and I-75 for twenty miles

Heavy commercial truck traffic (~20K/day)–

FHWA interested in traffic influences on PM

Multiple over-nighting facilities for Class 8trucks, including truck stop electrification–

CMAQ project interested in seeing effects of TSE

Proximity to ORNL/UT


Elevation Exaggeration=3x

Watt Road-Interstate 40/75 Interchange

Watt Road-I-40/75 Interchange

Three Major Truckstops

Weigh Station


Air Quality Studies: Location of Roadside, Truckstop, and Ridgetop(Background) Sampling Points

I-40/I-75

Watt Road

RoadsideElevation: 877 ft

Ridgetop(Background)Elevation: 1182 ft

TruckstopElevation: 920 ft

N

SW E

IdleaireInstallation


0.0

50.0100.0150.0

200.0250.0300.0

1 3 5 7 9 11 13 15 17 19 21 23

Hour of Day

Con

c(p

pb)

InterstateIdling

0.0

50.0100.0150.0

200.0250.0300.0

1 3 5 7 9 11 13 15 17 19 21 23

Hour of Day

Con

c(p

pb)

InterstateIdling

0.0

50.0100.0150.0

200.0250.0300.0

1 3 5 7 9 11 13 15 17 19 21 23

Hour of Day

Con

c(p

pb)

InterstateIdling

0.02.0

4.06.08.0

10.012.0

1 3 5 7 9 11 13 15 17 19 21 23

Hour of Day

Con

c(u

g/m

3)

InterstateIdling

0.02.0

4.06.08.0

10.012.0

1 3 5 7 9 11 13 15 17 19 21 23

Hour of Day

Con

c(u

g/m

3)

InterstateIdling

0.02.0

4.06.08.0

10.012.0

1 3 5 7 9 11 13 15 17 19 21 23

Hour of Day

Con

c(u

g/m

3)

InterstateIdling

NOx

Idling Trucks at Truckstops are Largest NOx and PM2.5 Contributor to Roadside Air Quality (Interstate Off Ramp)

Combination of data used to determine contribution of idling trucks to air quality at ramp site near roadway–

NOx, PM Monitoring–

Meteorological Data–

EPA’s MOBILE 6.2 Emission Factors

Despite >20,000 Trucks per day traveling interstate near interchange…–

100s of Idling trucks dominate the NOx and PM2.5 right next to the interstate

–

Traffic on interstate free-flowing for this study

PM2.5


Hot Spot” of High Pollutant Levels Formed by Idling Trucks at Truck Stops Near Roadway

Truckstops

form “Hot Spots”

of poor air quality

–

NOx, PM, MSATs elevated

Boundary of “Hot Spot”

difficult to define

–

Dependent on number of factors

Recent health risk studies link higher risk to residency near roadways

Further studies of “Hot Spots”

warranted

–

Health impacts of 2007/10 technology introduction

I-40/I-75

Watt Road



Measured NO and NO2 well above NAAQS for NO2

NAAQS NO2

Monthly Mean NO and NO2 Concentrations at Trailer #1

0

50

100

150

200

250

300

350

400

Dec-03 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 Jul-04 Aug-04Month

NO

(NO

2) C

once

ntra

tions

(ppb

)

NONO2

chart courtesy of Dr. Terry Miller, UT


1.8

4.8

9.9 9.8

24.3

16.7

0

5

10

15

20

25

30

Winter Summer

Form

alde

hyde

(mic

rog/

m^3

)

MinimumAverageMaximum

Ambient Formaldehyde at Truck Stop

MinimumRiskLevel

Measured Formaldehyde exceeds minimum risk level often


Mobile Source Air Toxics: Air Quality Near Truckstops

High Concentrations of Formaldehyde and Acetaldehyde observed at truckstop especially in winter

Formaldehyde may transport to roadside and background in winter

0

4

8

12

Truckstop Ramp Ridge

Con

cent

ratio

n (u

g/m

3)

Winter Formaldehyde

Summer Formaldehyde

Winter Acetaldehyde

Summer Acetaldehyde

Roadside Background


Monthly Average PM2.5 Concentrations at Trailer #1 & Trailer #2

0

10

20

30

40

50

Dec-03 Jan-04 Feb-04 Mar-04 Apr-04 May-04 Jun-04 Jul-04 Aug-04PM2.

5 C

once

ntra

tion

(ug/

m3)

Trailer #1

Trailer #2

Year-round PM2.5 levels at the truckstop exceed EPA’s required annual average

Max yearly average for PM2.5

chart courtesy of Dr. Terry Miller, UT


24-Average PM2.5 Concentrations at Trailer #2

0

20

40

60

80

100

120

140

10-Dec 25-Dec 9-Jan 24-Jan 8-Feb 23-Feb 9-Mar 24-Mar 8-Apr 23-Apr 8-May 23-May 7-Jun 22-Jun 7-Jul 22-Jul 6-Aug

Time (Hour)

24-H

our A

vera

ge P

M2.

5 C

once

ntra

tion

(ug/

m3)

24-Average PM2.5 Concentrations at Trailer #2


Mean Dp decreases when PM numbers increase, and vice versa

0

10

20

30

40

50

60

70

80

90

12:00AM

12:00PM

12:00AM

12:00PM

12:00AM

12:00PM

12:00AM

12:00PM

Time

Geo

met

ric M

ean

(nm

)

0.0E+00

5.0E+05

1.0E+06

1.5E+06

2.0E+06

2.5E+06

3.0E+06

Tota

l Num

ber (

#/cc

)

number


Size distributions show 10-fold increase in nano-particles and combustion aerosols during overnight hours

1.E+03

1.E+04

1.E+05

1.E+06

1.E+07

10 100 1000Dp (nm)

dN/d

logD

p

11:00 AM8:30 PM

~35 nm!


Winter OC & EC show more variation

July_Aug_OC_EC_sampling_summary_20041005

0

10

20

30

40

day night

Car

bon

Cou

nt (u

g/m

^3)

Truck Stop OC Truck Stop EC Road OC Road EC

error bars represent +/- COV

Summer

0

0

0

0

0

day night

Winter

0

25

50

16-Feb18-Feb20-Feb22-Feb23-Feb24-Feb25-Feb26-Feb27-Feb 2-Mar 3-Mar 4-Mar

PAH

Con

cent

ratio

n (n

g/m

^3)

0

12

24

36

48

PM2.

5 C

once

ntra

tion

(ug/

m^3

)

AcenaphthyleneAcenaphtheneFluorenePhenanthreneAnthraceneFluoroanthenePyrenePM 2.5

• The concentration of three- and four-ring PAHs follows the trend of PM2.5 concentration• PAHs are typically associated with combustion aerosols like diesel PM

>40 µg/m3 !


Lube-related alkanes heavy on some winter days

0

50

100

150

16-F

eb18

-Feb20

-Feb

22-F

eb24

-Feb26

-Feb28

-Feb

2-Mar

4-Mar

Con

cent

ratio

n (n

g/m

^3)

n-Eicosanen-Heneicosanen-Docosanen-Tricosanen-Tetracosanen-Pentacosane


Fast forward to a new understanding of crankcase emissions

Looking at evaluation methods for field-aged, retrofit DPF technology (EPA-OTAQ)

Crankcase emissions difficult to measure–

No vacuum or pressure can be exerted on the engine–

Particle sizes go well beyond SMPS–

Aerosol Particle Sizer very sensitive to concentration - >1000:1 dilution required

Contribute directly to PM2.5 as primary organic aerosol


Exhaust Sampling System

DPF

Engine: 1999 Cummins B5.9 Diesel

Sampler forcrankcase PM


Crankcase Emissions Sampling

System

Pri

mar

y D

iluti

on T

unne

l

CrankcaseHEPA

198 LPM To Pump (Roots Blower)

RoomAir

RoomAir

~8 LPM

~190 LPM

4 in.

Draft tube

1 LPM

70 mm filters

Isokinetic probe

Secondary Dilution Tunnel

99 LPM

Mass Flow Controller

HEPA-filtered air

Re=8500Isokinetic probe

Aerodynamic Particle Sizer**

5 LPM95 LPM

To Pump

SMPS*

* Scanning mobility particle sizer

(SMPS): measures particles < 1 um** Aerodynamic particle sizer: measures particles > 1 um

Manometer to ensure vacuum not exerted on crankase

1.5 in.


Crankcase PM Mass Emissions

Total crankcase PM emitted during FTPMass collected: ~ 63 mg each filter

Exhaust PM collected during FTPMass sampled:~1.1 mg


Transient Test

Cold FTP Hot FTP

Cra

nkca

se P

M M

ass

Emis

sion

s R

ate

(g/h

p-hr

)

0.000

0.005

0.010

0.015

0.020Engine BaselineIncreased BackpressureDPF Present

Crankcase PM Mass Emissions for FTP Cycles

SOF

Soluble organics~90% of

crankcase PM

Crankcase emissions ~ 3 X greater than DPF treated exhaust emissionsFor hot FTP:

FTP w. DPF


dp (nm)

101 102 103 104 105

dN/d

logd

p (#

/cm

3 )

0.0

5.0e+7

1.0e+8

1.5e+8

2.0e+8

2.5e+8

SMPSAPS

µg = 114 ± 2 nm Ctot = 2.9 x 107 #/cm3

dp (nm)

101 102 103 104 105

dN/d

logd

p (#

/cm

3 )

0.0

5.0e+7

1.0e+8

1.5e+8

2.0e+8

2.5e+8

SMPSAPS

µg = 159 ± 2 nm Ctot = 1.4 x 108 #/cm3

Crankcase Emissions Number-Size Distribution

1400 RPM, 300 ft lbs

Increased Backpressure

Engine Baseline

Backpressure 280 mbarat rated speed (1400 RPM)

dp

> 540 nmCtot

= 1.1 x 107

dp

> 540 nmCtot

= 1.8 x 106


Summary

Winter temperatures, overnight stays influenced PM2.5

–

higher in truck stop, despite heavy truck traffic on I-40

OC/EC dominated by biogenics

in summer levels of both EC and OC higher in winter

–

much more variability in winter

Lube and PAH important in PM2.5

at the truck stop

Formaldehyde levels can get high in winter

–

strongly dependent on temperature/mixing

Crankcase PM

–

mass emissions ~ 3 X greater than DPF-out PM emissions over FTP

–

For dp

> 540 nm, total number concentration was about 1 x 107

for case of elevated backpressure

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PM , Air Toxics, And Crankcase Emissions In The Truck Stop … · 2015-08-28 · Managed by...

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