control of toxics and nanoparticle emissions from cng-fueled, … · 2017. 9. 14. · mridul gautam...

Control of Toxics and Nanoparticle Emissions from CNG-Fueled, Heavy-duty Transit Buses

Mridul GautamNational Research Center for Alternative Fuels,

Engines and EmissionsDepartment of Mechanical and Aerospace Engineering

West Virginia University

Hemanth Kappanna, Scott Wayne,

Bobby John, Dan CarderCenter for Alternative Fuels, Engines and Emissions

Department of Mechanical and Aerospace EngineeringWest Virginia University

Adewale OshinugaSouth Coast Air Quality Management District

Bob Kreeb, Howard ParisEnvironment Canada

Ted TadrousECS

Lisa GrahamEnvironment Canada

ObjectivesGlobal Objective

To reduce toxic pollutants and nanoparticle emissions from CNG-fueled heavy-duty transit buses.

Specific ObjectivesCharacterize the emissions, including particle size distribution from

Cummins Westport C8.3G+ natural gas engine with and without OEM aftertreatment device, an oxidation catalyst (PHASE I).

Develop an exhaust aftertreatment device based on the baseline engine emissions results. Test and validate emission reduction potential of the new exhaust aftertreatment device (PHASE II)

The new “WVU-Lubrizol” Exhaust Aftertreatment System was a combination of a catalyzed PM filter followed by an oxidation catalyst.

Retest the exhaust aftertreatment device after six months of on-road demonstration to evaluate for any deterioration in the emissions reduction performance (PHASE III)

Test Vehicle and Engine Specifications

850 lb-ft @ 1400rpmPeak Torque

280 hp @ 2400rpmEngine Power rating

Auto Grade Natural GasFuel Type

1330 lbsNet Weight

Premixed Air/FuelFuel Injection

Spark IgnitedIgnition

10:1Compression Ratio

6No of Cylinders

8.3 litersEngine Displacement

2000Engine Model Year

C-Series, Gas PlusEngine Series

Cummins WestportEngine Manufacturer

1998Bus Model Year

OrionBus Manufacturer

Certified with a catalyst for California ULEV levels

NOx: 1.53 g/bhp-hrNMHC: 0.21 g/bhp-hr

Total PM: 0.008 g/bhp-hrCO: 0.8 g/bhp-hr

Test Vehicle:Orion, standard 40-foot, high-floor design

Test Cycle: Quad – Central Business District Cycle

Transportable Chassis Dynamometer Laboratory

PM and Speciation Sampling System

Total PM

PM1Cyclone

PM2.5 Cyclone

PM10 Cyclone

Toxic Gas Sampling System

Temperature Control Module

PUF/XAD/PUF Cartridge (not shown) connection

Sampling Media, and Methods used to Analyze Unregulated Emissions

Gravimetric Analysis16.7Size selective cyclone and 47 mm T60A20 filterPM1.0 mass

Gravimetric Analysis16.7Size selective cyclone and 47 mm T60A20 filterPM2.5 mass

Gravimetric Analysis28.3Size selective cyclone and 47 mm T60A20 filterPM10 mass

Gravimetric Analysis8170mm teflon coated glass-fiber filter (T60A20)Total PM mass

Accelerated solvent/microwave extraction followed by GC/MS. Nitro-PAHs separated by HPLC before GC/MS.

6070 mm teflon-impregnated, glass fiber filter (TX40) backed by PUF/XAD/PUF adsorbing cartridge

PAHs and nitro-PAHs, Hopanes and Steranes

Thermal Optical Reflectance (TOR) for EC/OC. Ion chromatography and automated Colorimetry for inorganic ions

16.7PM2.5 cyclonic separator with 47mm pre-fired quartz filter

EC/OC and Inorganic Ions

X-Ray Fluorescence metal detection16.7PM2.5 cyclonic separator with 47mm teflon filter

Metals and elemental analysis

High Performance Liquid chromatography (HPLC) for separation and quantization

1Two Sep-Pak cartridges impregnated with acidified 2,4-DNPH

Carbonyl Compounds

GC/MS/FID equipped with pre concentrator

6L @ 10psi(can)10L bag

Tedlar bags for onsite analysis and steel canisters for lab analysis

Volatile Organic Compounds (VOC)

MethodFlow Rate (lpm)Sampling MediaCompound Class

Phase I: Average Carbonyls Emissions

3.35

E-01

2.54

E+00

2.18

E-021.

10E+

00

1.91

E-01

2.21

E+00

1.40

E-02

1.28E+01

0.00E+00

2.00E+00

4.00E+00

6.00E+00

8.00E+00

1.00E+01

1.20E+01

1.40E+01

Formaldehyde Acetaldehyde Acetone Propionaldehyde

g/m

ile

Baseline

OEM Oxy Catalyst

3.51

E+0

0

1.57E+01

0.00E+002.00E+004.00E+006.00E+008.00E+001.00E+011.20E+011.40E+011.60E+011.80E+01

Baseline OEM Oxy Catalyst

Phase I

g/m

ile

PropionaldehydeAcetoneAcetaldehydeFormaldehydeTotal

Bseline vs. OEM Oxy CatalystFormaldehyde: 91%Acetaldehyde: 43%Acetone: 13%Propionaldehyde: 36%Total Aldehyde: 77%

Phase I: Average Poly Aromatic Hydrocarbons Emissions

1.18

E-04

2.12

E-05

0.00E+00

2.00E-05

4.00E-05

6.00E-05

8.00E-05

1.00E-04

1.20E-04

1.40E-04

Baseline OEM Oxy Catalyst

Phase I

g/m

ile

Naphthalene AcenaphthyleneAcenaphthene Fluorene2-Me-Fluorene PhenanthreneAnthracene FluoranthenePyrene Retene1-Me-Pyrene Benzo(g,h,i)FluorantheneBenzo(g,h,i)Perylene Benzo(a)AnthraceneTriphenylene ChryseneTotal

Baseline vs. OEM Oxy CatatlystTotal PAH: 82%

Phase I: Average Engine Wear & Lube Oil Additive Emissions

1.23

E-03

3.95

E-04

2.31

E-04

ND

ND

ND

0.00E+00

2.00E-04

4.00E-04

6.00E-04

8.00E-04

1.00E-03

1.20E-03

1.40E-03

Iron Copper Lead

g/m

ile

BaselineOEM Oxy Catalyst

2.30

E-04

2.82

E-04

4.65

E-04

4.87

E-04

1.99

E-04

6.58E-04

ND

6.30E-04

0.00E+00

1.00E-04

2.00E-04

3.00E-04

4.00E-04

5.00E-04

6.00E-04

7.00E-04

Phosphorus Sulfur Calcium Zinc

g/m

ile

Phase I: Steady State (20 mph) Particle Size Distribution, Cold and Warm Oxidation Catalyst

10 1000.0

2.0x105

4.0x105

6.0x105

8.0x10 5

1.0x106

SS 20mph With Oxidation Catalyst--coldSS 20mph With Oxidation Catalyst--hot

Particle diameter (nm)

Part

icle

Con

cent

ratio

n dN

/dlo

gDp

(#/c

m3 )

Burlingame, (2004)

Phase I: Concentration Trace of Different Size Particles With and Without

the OEM Catalyst84nm QCBD

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

0 200 400 600 800 1000

Time (Sec)

Nor

mal

ized

con

cent

ratio

n (d

N/d

log

Dp)

#/c

m^3

84nm With CAT84nm Without CAT

19nm QCBD

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

0 200 400 600 800 1000 1200 1400 1600

Time (Sec)

Nor

mal

ized

con

cent

ratio

n (d

N/d

log

Dp)

#/

cm^3

19nm With CAT19nm Without CAT

Test Cycle Specification

Name: Central Business District cycle (CBD)Duration: 560/590 sAverage Speed: 12.57 mphMaximum Speed: 20 mphDriving Distance: 2 milesMaximum Acceleration: 1.79 m/s2

WVU-Lubrizol Aftertreatment System(Oxidation Catalyst was Located Downstream of the PM Filter)Diesel Particulate Filter

Silicon Carbide, segmented honey comb (11.25” X 12”) 200 square CPI cell densityPlatinum coated on proprietary wash-coatPassive regeneration over duty cycles producing exhaust temperature 280oC - 320oC for >25% of the time

Oxidation CatalystCordierite flow-through monolith, (10.5” X 6”)400 square CPI cell densityPt and Pd (1:3) coated on proprietary wash-coat

Phase II: Transient Particle Concentrations

19nm QCBD

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

0 200 400 600 800 1000 1200 1400 1600

Time (Sec)

Nor

mal

ized

con

cent

ratio

n (d

N/d

log

Dp)

#/

cm^3

19nm With OEM CAT

19nm Without OEM CAT

19nm With PM trap and Oxi CAT

10 1000.0

5.0x10 3

1.0x10 4

1.5x10 4

2.0x10 4

2.5x10 4

3.0x10 4Pa

rtic

le C

once

ntra

tion

dN

/dlo

gDp

(#/c

m^3

)

Particle diameter (nm)

Background 1

Phase II: Steady State Particle Size Distribution

Phase II: Steady State Particle Size Distribution

1 10 100

0

1x10 6

2x10 6

3x10 6

4x10 6

5x10 6Pa

rtic

le C

once

ntra

tion

dN/d

logD

p(#

/cm

^3)

Particle Diameter (nm)

Steady State 25Mph Cold

Steady State 25Mph Hot

Particle Size Distribution with only Trap

10 1000.0

5.0x103

1.0x104

1.5x104

2.0x104

2.5x104

3.0x104

Part

icle

Con

cent

ratio

n dN

/dlo

gDp

(#/c

m^3

)

Particle diameter (nm)

Background 1

0 20 40 60 80 100 120 140 160 180

1x104

2x104

3x104

4x104

5x104

6x104

Particle diameter (nm)

Steady state 25Mph with Oxidation Catalyst and Trap

Phase II: Steady State Particle Size Distribution

Part

icle

con

cent

ratio

n dN

/dlo

gDp

(#/c

m^3

)

West Virginia University ,Morgantown,WV 26506

Sunline Transit Bus Transient Operation Quad CBD; Catalyzed PM Filter Only (Phase II)

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

0 200 400 600 800 1000 1200 1400 1600 1800

Time (sec)

Nor

mal

ized

par

ticle

con

cent

ratio

n N

/dlo

g D

p (#

/cm

^3)

13.29 nm

West Virginia University ,Morgantown,WV 26506

Transit Bus Transient Operation Quad CBD; Catalyzed PM Filter and

Oxidation Catalyst (Phase II)

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

0 100 200 300 400 500 600 700 800 900 1000

Time (sec)

Nor

mal

ized

con

cent

ratio

n dN

/dlo

g D

p (#

/cc)

18.8 nm

Average Regulated Emissions13

.20

0.38

0.13

0.14

37.7

0

32.8

0

23.4

0

1.08

0.34

0.19 0.60

0.04

0.02

0.00

0.06

0.01

17.1

0 27.6

0

21.0

0

N/A

0

5

10

15

20

25

30

35

40

Baseline OEM Oxy Cat WVU-LubrizolAftertreatment

Baseline WVU-LubrizolAftertreatment

Phase I Phase II Phase III

g/m

ile

CO

NOX

NMHC

TPM

0.00

1

0.00

7

0.03

9

0.01

5

0.06

4

0.000.010.020.030.040.050.060.07

Bas

elin

e

OE

M O

xy C

at

WV

U-L

ubriz

olA

ftertr

eatm

ent

Bas

elin

e

WV

U-L

ubriz

olA

ftertr

eatm

ent

Phase I Phase II Phase III

g/m

ile

Average Carbonyl Emissions

0.02

8

0.00

6

0.01

6

0.01

2

2.04

3.51

2.04

15.6

6

0

2

4

6

8

10

12

14

16

18

Bas

elin

e

BK

G

OEM

Oxy

cat

BK

G

WVU

-Lub

rizol

Afte

rtrea

tmen

t

BK

G

WVU

-Lub

rizol

Afte

rtrea

tmen

t

BK

G

Phase I Phase II Phase III

g/m

ile

propionaldehydeacetoneacetaldehydeformaldehydeTotal

1.17

E-02

1.62

E-02

5.69

E-03

2.79E-02

0.0000.0050.0100.015

0.0200.0250.030

WVU

-Lub

rizol

Aft

ertr

eatm

ent

BK

G

WVU

-Lub

rizol

Aft

ertr

eatm

ent

BK

G

Phase II Phase III

g/m

ile

Average Toxic Gas Emissions

6.84

E-03

5.74

E-03

6.84

E-03

6.99

E-03

6.05

E-03

4.32

E-03 6.

15E-

03

1.52E-02

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

Bas

elin

e

Bac

kgro

und

OEM

Oxy

Cat

alys

t

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

Phase I Phase II Phase III

Canister Sample

g/m

ile

o-Xylenem&p-Xylenee-BenzeneTolueneBenzene1,3-ButadieneTotal

Average Lube Oil Additive Emissions

ND

NDND

ND ND

ND

0.0000

0.0002

0.0004

0.0006

0.0008

0.0010

0.0012

0.0014

0.0016

0.0018

0.0020

Bas

elin

e

Bac

kgro

und

OEM

Oxy

Cat

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

Phase I Phase II Phase III

g/m

ile

ZincCalciumSulfurPhosphorus

Average Engine Wear Emissions

ND ND

ND ND ND ND

0.0000

0.0002

0.0004

0.0006

0.0008

0.0010

0.0012

0.0014

Bas

elin

e

Bac

kgro

und

OEM

Oxy

Cat

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

Phase I Phase II Phase III

g/m

ile

CopperIron

Transit Bus Total Ozone Forming Potential (CBD)

0

20000

40000

60000

80000

100000

120000

140000

ECD+CRT

ECD1+CRT

ECD1+NONE

CARB+NONE

CNG+NONE

CNG+NONE

C8.3G+, N

ONEC8.3

G+, OEM O

C

C8.3G+, W

VU-Lubrizo

l EAD

mg-

oz/m

i

Carbonyl UncorrectedVOC Uncorrected

0100200300400500600700

ECD

+CR

T

ECD

1+C

RT

ECD

1+N

ON

E

CA

RB

+NO

NE

C8.

3G+,

WVU

-Lu

briz

ol E

AD

Phase III: Transit Bus Steady State Operation 25 mph

PM Filter and Oxidation Catalyst

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1 10 100 1000Particle Diameter (nm)

dN/d

logd

P(#/

cm3 )

With Cat & Trap-LDMA-Day 1With Cat & Trap-NDMA-Day 2Baseline-NDMA-Day 3BKGD-LDMA Day 1BKGD-NDMA Day 2BKGD-NDMA-Day 3

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1 10 100 1000Particle Diameter (nm)

dN/d

logd

P(#/

cm3 )

With Cat & Trap-LDMA-Day 1BKGD-LDMA-Day 1Baseline-NDMA-Day 3BKGD-NDMA-Day 3

Phase III: Transit Bus Steady State Operation 35 mph

PM Filter and Oxidation Catalyst

Quadratic Response Surface of Mutagenicity as Function of Engine Speed and Load

1.344e7 2.637e7 3.931e7 5.225e7 6.519e7 7.812e7 9.106e7 1.04e8 1.169e8 1.299e8 above

Dose Response vs Engine Speed and LoadFUEL: DF2 z=-3.212e8+2.692e7*x+9.162e6*y-4.783e5*x*x-2.544e5*x*y+1.186e5*y*y

FUEL: FT z=-4.321e8+3.487e7*x+1.937e7*y-6.486e5*x*x-1.844e5*x*y-5.983e5*y

X-axis: SpeedY-axis: BMEP

FUEL: DF2 FUEL: FT

Conclusions• Distance specific total PM emissions were reduced by 90-98% with

WVU-Lubrizol EAS compared to baseline values.• Emissions of TACs were reduced by more than 99% and were

below the background levels.• Emissions of carbonyls were reduced below background levels with

WVU-Lubrizol EAS.• Emissions of toxic gases (BTEX & 1,3-butadiene) were reduced

below background levels with WVU-Lubrizol EAS.• PAH emissions were reduced by 80% and were below the

background levels.• Emissions of engine wear elements and lube oil additives were

effectively trapped by the WVU-Lubrizol EAS reducing them to below detection levels.

• Number concentration of nanoparticles were reduced to the level found in the background both by the new and aged WVU-Lubrizol EAS.

• No deterioration was observed in the emissions reduction performance of the in-field demonstrated WVU-Lubrizol EAS.

Acknowledgements

West Virginia University,Morgantown,WV 26506

Funding for the study was provided by:

•South Coast Air-Quality Management District

•The Gas Company

Thank You

Average Polycyclic Aromatic Hydrocarbons

1.18

E-04

3.32

E-05

2.12

E-05

3.32

E-05

2.29

E-05 4.34

E-05

1.65

E-04

2.18E-04

0.00E+00

5.00E-05

1.00E-04

1.50E-04

2.00E-04

2.50E-04

Bas

elin

e

Bac

kgro

und

OEM

Oxy

Cat

alys

t

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

WVU

-Lub

rizol

Afte

rtrea

tmen

t

Bac

kgro

und

Phase I Phase II Phase III

g/m

ile

Naphthalene AcenaphthyleneAcenaphthene Fluorene2-Me-Fluorene PhenanthreneAnthracene FluoranthenePyrene Retene1-Me-Pyrene Benzo(g,h,i)FluorantheneBenzo(g,h,i)Perylene Benzo(a)AnthraceneTriphenylene ChryseneTotal

Phase III: Trace of Particle Concentrations during a QCBD Cycle

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400

Time (s)

Parti

cle

Con

cent

ratio

n dN

/dlo

gdp

(#/c

m^3

)

16.8nm from Baseline Engine16.8 nm with Aged WVU-Lubrizol Aftertreatment

1.00E+00

1.00E+01

1.00E+02

1.00E+03

1.00E+04

1.00E+05

1.00E+06

1.00E+07

1.00E+08

1 10 100 1000Dp (nm)

dN/d

logD

p

Dallas Bus 1 -1Dallas Bus 1 -2Dallas Bus 2 -1Dallas Bus 2 -2Dallas Bus 2 -3Dallas Bus 2 -4Dallas Bus 3 -1Dallas Bus 3 - 2Dallas Bus 4 -1Dallas Bus 4 - 2Dallas Bus 5 -1 Dallas Bus 5 -2Dallas Bus 5 -3Dallas Bus 5 -4Location 2 DR = 24

Bus 5GMD -33 nm

Bus 4GMD - 50 nm

Bus 3GMD 41 nm

Bus 2GMD 47 nm

Bus 1GMD 20 nm

Langley Dataat location 2GMD - 54 nm

Typical Engine Exhaust Particle Size Distributions for Different Buses At Different Locations

(Gautam and Mehta, 2001)