Modification and Validation of Modification and Validation of Diesel Particulate Matter Diesel Particulate Matter

Cassette for PM-1.0 Sampling at Cassette for PM-1.0 Sampling at Different Flow RatesDifferent Flow Rates

Saulius Trakumas and Peter HallSKC Inc., Eighty Four, Pennsylvania

Objective:Objective:

Modify Diesel Particulate Matter (DPM) Cassette for PM-1.0 sampling at various flow rates.

Outline:Outline:

Why PM-1.0 is important

DPM cassette: purpose, operation, and performance

Experimental validation of modified DPM Cassette

Conclusions

There is evidence from epidemiological studies that adverse health effects are associated with increased exposure to fine and ultra fine particles.

Particulates smaller than 1.0 micrometer (PM-1.0) represent a significant fraction of the emissions from many industrial sources.

Airborne Particle Size Distribution in a Diesel Equipped MineAirborne Particle Size Distribution in a Diesel Equipped Mine

Aerodynamic Particle Diameter, da, m

0.01 0.1 1 10 100

Du

st M

ass,

M, m

g/m

3

0

1

2

3

Diesel Particulate

Mine Dust

Total PM mass measurements can be strongly influenced by mechanically produced large particles, which may not be associated with adverse health effects.

Size-selective Sampling Using ImpactorSize-selective Sampling Using Impactor

AccelerationNozzle

ImpactionPlate

AirStreamline

Impacted Particle

Particle too Small to Impact

Particle Collection Efficiency CurveParticle Collection Efficiency Curve

Aerodynamic Particle Diameter, da, m

Co

llect

ion

Eff

icie

ncy

, E=

(1-C

DO

WN/C

UP)1

00, %

0

25

50

75

100

d50

Actual

Ideal

AccelerationNozzle

ImpactionPlate

AirStreamline

Impacted Particle

Particle too Small to Impact

Diesel Particulate Matter CassetteDiesel Particulate Matter Cassette

Diesel Particulate Matter CassetteDiesel Particulate Matter Cassette

Inlet

Cassette Body

Impactor Assembly

Filter (in capsule)

Outlet

Diesel Particulate Matter CassetteDiesel Particulate Matter Cassette

Impactor Assembly

DPM Cassette Performance at 2.0 Lpm DPM Cassette Performance at 2.0 Lpm

Aerodynamic Particle Diameter, da, m

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Co

llect

ion

Eff

icie

ncy

, E, %

0

25

50

75

100

Dioctyl Phthalate

Aerodynamic Particle Diameter, da, m

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Co

llect

ion

Eff

icie

ncy

, E, %

0

25

50

75

100

Glass Spheres

Aerodynamic Particle Diameter, da, m

0.0 0.5 1.0 1.5 2.0 2.5 3.0

Co

llect

ion

Eff

icie

ncy

, E, %

0

25

50

75

100

PSL particles

Impaction Theory Predicts:Impaction Theory Predicts:

The original DPM Cassette will sample PM-1.0 when operated at approximately 1.0 Lpm flow rate.

In order to sample PM-1.0 at higher flow rates the size of impactor orifices should be increased.

During this study the DPM Cassette impactors with orifice sizes of 0.6, 0.9, 1.0, 1.1, and 1.4 mm were tested at different flow rates.

Experimental Experimental SetupSetup

Clean Air(20-100 Lpm )

ChargeNeutralizer

TurbulenceGenerators

Honeycom bFlow Straightener

Clear PlexiglassCylinder

(D=12 , H=48 )” ”

AccessPort

Foam

Sam plingLines

TestDevice

To Filter

APS is switched between twosampling lines

Add/SubtractM akeup Flow

AerosolGenerator

Aerodynam icParticle

Sizer

E = 100%1 - CDOWN

CUP

Aerodynamic Particle Diameter, da, m

0 1 2 3 4 5

Co

llect

ion

Eff

icie

ncy

, E, %

0

25

50

75

100

Dioctyl Phthalate

Glass Spheres

QS=3.0 Lpm ,

QS=2.0 Lpm ,

QS=1.0 Lpm ,

Performance of the Original DPM Cassette (d=0.6 mm)Performance of the Original DPM Cassette (d=0.6 mm)

Performance of the Modified DPM Cassette (d=1.0 mm)Performance of the Modified DPM Cassette (d=1.0 mm)

Aerodynamic Particle Diameter, da, m

0 1 2 3 4 5

Co

llect

ion

Eff

icie

ncy

, E, %

0

25

50

75

100

Dioctyl Phthalate

Glass Spheres

, QS=5.0 Lpm , QS=4.0 Lpm

QS=3.0 Lpm ,

QS=2.0 Lpm ,

QS=1.0 Lpm ,

Performance of the Modified DPM Cassette (d=1.4 mm)Performance of the Modified DPM Cassette (d=1.4 mm)

Aerodynamic Particle Diameter, da, m

0 1 2 3 4 5

Co

llect

ion

Eff

icie

ncy

, E, %

0

25

50

75

100

Dioct

yl

Phtha

late

Gla

ss

Spher

es

, QS=10.0 Lpm , QS=8.0 Lpm

QS=5.0 Lpm ,

QS=3.0 Lpm ,QS=1.0 Lpm ,

Sampling Flow Rate, QS, Lpm

0 2 4 6 8 10

50%

Cu

t D

iam

eter

, d5

0,

m

0

1

2

3

4

5

Dioctyl Phthalate

Glass Spheres

d=1.4 mm

d=1.0 mm

d=0.6 mm

50% Cut-off Size at Different Flow Rates50% Cut-off Size at Different Flow Rates

Sampling Flow Rate, QS, Lpm

0 2 4 6 8 10

50%

Cu

t D

iam

eter

, d5

0,

m

0

1

2

3

4

5

Theory for solid collection surface

Sampling Flow Rate, QS, Lpm

0 2 4 6 8 10

50%

Cu

t D

iam

eter

, d5

0,

m

0

1

2

3

4

5

Theory for porous collection surface

Impactor Orifice Diameter as a Function of the Flow Rate Impactor Orifice Diameter as a Function of the Flow Rate for Sampling PM-1.0 for Sampling PM-1.0

Sampling Flow Rate, QS, Lpm

0 2 4 6 8 10

Imp

acto

r O

rifi

ce D

iam

eter

, dO

R, m

m

0.0

0.5

1.0

1.5

2.0

Experimental data

Theoreticallypredicted

ConclusionsConclusions

The original DPM Cassette can be used for PM-1.0 sampling when operated at 1.0 Lpm.

Results of this study can be used to modify the DPM Cassette for sampling PM-1.0 at preferred flow rates ranging from 1.0 to 10.0 Lpm.