1

1

Biodiesel and Renewable Diesel Emissions Study(Regulated Emissions)

Dec. 8th, 2010

Kwangsam Na

California Environmental Protection AgencyCalifornia Environmental Protection Agency

AirAir Resources BoardResources Board

Heavy Duty Diesel Emission Testing LaboratoryMobile Source Control Division

2

Regulated Emissions

(PM, NOx, CO, THC)

Global Warming Gas

(CO2)

Blend Levels

(20%, 50%, 100%)

Feed Stocks

(Soy-based biodiesel, Animal fat biodiesel,

Renewable diesel)

Driving Cycles

(UDDS, Cruise)

Objectives

To look at the impact of blend levels, feed stocks, and driving cycles on regulated emissions and a global warming gas.

3

Emission Testing

2

4

Vehicles Tested

Veh. #1: 2000 Freightliner C15 Caterpillar Veh. #2: 2006 International ISM 370

Veh. #3: 2008 Freightliner Mercedes Benz MBE 4000

5

450at 1900 rpm

370at 2100 rpm

550 at 1800 rpm

Horse power/Torque

CARB diesel,Soy-based biodiesel(S20, S50, S100),

Animal-based( A20, A50, A100),

12.8

Cruise:57,490

UDDS:43,480

8,000EGR,DOC,DPF

2008 FreightlinerMercedes Benz

MBE 4000

CARB diesel,Soy-based biodiesel(S20, S50, S100),

Animal-based( A20, A50, A100),

10.8

Cruise:61,189

UDDS:43,480

93,000EGR 2006 InternationalISM 370

CARB diesel,Soy-based biodiesel(S20, S50, S100),

Animal-based( A20, A50, A100),Renewable diesel(R20, R50, R100)

14.6

Cruise:58,744

UDDS:43,861

34,0002000 Freightliner C15 Caterpillar

Test fuelsEngine

Displacement(liter)

Inertia weight(lbm)

Odometer(miles)

EmissionControlDevices

Make/model/year

Description on vehicles and fuels tested

6

Driving Cycles Tested

II. 50 mph Highway Cruise: High load cycle

I. Urban Dynamometer Driving Schedule (UDDS): low load cycle

0

20

40

60

80

0 200 400 600 800Time (s)

Spe

ed (

mile

/h)

0

20

40

60

80

0 200 400 600 800 1000

Time (s)

Spe

ed (

mile

/h)

3

7

Emission Data Measured

Regulated components Non-regulated components

• Oxides of Nitrogen (NOx)

• Particulate Matter (PM)

• Total Hydrocarbons (THC)

• Carbon Monoxide (CO)

• Carbon Dioxide (CO2)

• Nitrous Oxide (N2O)

• NO2 fractions in NOx

8

Constant Volume Sampling (CVS) Dilution Tunnel and PM sampling Conditions

Horiba full flow dilution tunnel

Horiba PM filter unit

• Dilution air temp.: 25±5 oC• Heated filter temp.: 47±5 oC• Filter face velocity: 100±10 cm/s

9

PM and Gas Analysis

PM: Mettler Toledo UMX2Micro Balance

Readability: 0.1 µg

Gases: Horiba MEXA 7200DExhaust Gas Analyzer

• CO, CO2: NDIR (Non-dispersive infrared)• THC: FID (flame ionization detector)• NOx: CLD (Chemi-luminescence detector)

Detector for Gas Analysis

4

10

Test R

esults

11

Drift o

f NOxEmission fo

r

2000 Vehicle

10

15

20

25

CARB-Soy

S20

S50

S100

CARB-Animal

A20

A50

A100

CARB-Renewable

R20

R50

R100

CARB-2

A20

A100

CARB-Soy

S20

S50

S100

CARB-Animal

A20

A50

A100

CARB-Renewable

R20

R50

R100

CARB-2

A100

S20

UD

DS

Cru

ise

Cy

cles &

Fu

el B

len

ds

NOx Emission Rate (g/mile)

12 14 16 18

11-28-0812-18-08

1-7-091-27-09

2-16-09

Testin

g d

ate

NOx emissions (g/mile)

CA

RB

Diesel

12

PM Emissions

0.00

0.10

0.20

0.30

CARB

S20

S50

S100

A20

A50

A100

R20

R50

R100

CARB

B20

B50

B100

A20

A50

A100

R20

R50

R100

Soy base

Anim

al baseR

enewable

Soy base

Anim

al baseR

enewable

Double U

DD

S50 M

PH

Highw

ay Cruise

Emission rate for PM(g/mi)

20002006

2008

5

13

CO Emissions

0.0

1.0

2.0

3.0

4.0

CA

RB

S20

S50

S10

0

A20

A50

A10

0

R20

R50

R10

0

CA

RB

B20

B50

B10

0

A20

A50

A10

0

R20

R50

R10

0

Soy base Animal base Renewable Soy base Animal base Renewable

Double UDDS 50 MPH Highway Cruise

Em

issi

on

rat

e fo

r C

O(g

/mi)

2000 2006 2008

14

0.0000

0.0002

0.0004

0.0006

0.0008

0.0010

0.0012

0.0014

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

Elapsed time (s)

TH

C (

gram

)

0.000

0.005

0.010

0.015

0.020

0.025

0.030

0.035

CO

(gr

am)

THC (g) CO (g)

1st UDDS cycle 2nd UDDS cycle

THC and CO Emissions

Before and After the DOC is Warmed up(2008 model year vehicle, CARB diesel, double UDDS cycle)

0

100

200

300

400

0 500 1000 1500 2000

Elapsed time (s)

Exh

aust

tem

per

atu

re (

oC

)

0.0000

0.0002

0.0004

0.0006

0.0008

0.0010

0.0012

0.0014

TH

C e

mis

sio

ns

(g)

Before DOC+DPF After DOC+DPF THC (g)

Exhaust temperature

THC emission

100 oC

15

THC Emissions

0.0

0.2

0.4

0.6

CA

RB

S20

S50

S10

0

A20

A50

A10

0

R20

R50

R10

0

CA

RB

B20

B50

B10

0

A20

A50

A10

0

R20

R50

R10

0

Soy base Animal base Renewable Soy base Animal base Renewable

Double UDDS 50 MPH Highway Cruise

Em

issi

on

rat

e fo

r T

HC

(g

/mi)

2000 2006 2008

6

16

CO2 Emissions

0

500

1000

1500

2000

CA

RB

S20

S50

S10

0

A20

A50

A10

0

R20

R50

R10

0

CA

RB

B20

B50

B10

0

A20

A50

A10

0

R20

R50

R10

0

Soy base Animal base Renewable Soy base Animal base Renewable

Double UDDS 50 MPH Highway Cruise

Em

issi

on

rat

e fo

r C

O2

(g/m

i)

2000 2006 2008

17

NO2 Fractions in total NOx emissions

0

20

40

60

80

100

CA

RB

S20

S50

S10

0

A20

A50

A10

0

R20

R50

R10

0

CA

RB

B20

B50

B10

0

A20

A50

A10

0

R20

R50

R10

0

Soy base Animal base Renewable Soy base Animal base Renewable

Double UDDS 50 MPH Highway Cruise

NO

2 in

to

tal N

Ox

(%)

2000 2006 2008

18

Summary

Continued on next slide

• Average PM, THC and CO emission rates decreased with increasing blend level of biodiesel regardless of the driving cycles and the vehicle model year.

• For the 2008 vehicle, THC and CO emissions sharply dropped when the DOC is warmed up and were not affected by biodiesel concentration. PM emissions were close to or below detection limit. In other words, the use of biodiesel did not show any benefits in the reduction of THC, CO and PM emissions when used with DOC/DPF.

• The 2008 vehicle equipped with DOC and DPF showed the lowest regulated pollutant emissions among the vehicles tested. However, this vehicle was not effective at reducing CO2 emissions.

7

19

Continued on next slide

Summary (Contd)

• NOx significantly increased for 50% and higher biodiesel blends regardless of the driving cycles and the vehicle model year. Increase in NOx emission was most noticeable for the 2008 vehicle.

• For renewable diesel, NOx shows a decreasing trend with increasingblend level for both driving cycles. However, its significant increase was observed for pure renewable diesel.

• For the 2000 vehicle with no NOx control device (EGR), more NOx was emitted for the highway cruise cycle (having high load) than the UDDS cycle (with lower load). However, this emission pattern was opposite for vehicles equipped with EGR, showing a better NOx reduction efficiency under higher load driving cycle.

20

Summary (contd)

• CO2 emissions were not significantly impacted by biodiesel blend levels for different vehicle model year except for renewable diesel blend levels higher than 50% which significantly decreased CO2 emissions for both driving cycles.

• No significant impact of biodiesel was found on NO2 fractions for all vehicles tested. The NO2 fractions were the highest for the 2008 vehicle equipped with a DOC. The 2006 vehicle equipped with EGR showed ahigher NO2 fraction than the 2000 vehicle with no EGR.

21

Thank you for your attention !!!