Open Path Methods Building Environment Research & Education AgAirQuality.com Agricultural and Biological Engineering Purdue University Albert J. Heber,

Open Path Methods

Building EnvironmentResearch & Education

AgAirQuality.com

Agricultural and Biological Engineering

Purdue University

Albert J. Heber, [email protected]

Biocurtain at Laying House

Biocurtain over 3 fans

Lab

Inside Biocurtain at Layer House

NRC Report on Air EmissionsEmissions Global/Nat. Local Concern

NH3 Major Minor N-Dep/PM2.5

N2O Significant Insignificant Climate

NOx Significant Minor Haze/Health

CH4 Significant Insignificant Climate

VOCs Insignificant Minor Quality

H2S Insignificant Significant Quality

PM10 Insignificant Significant Haze

PM2.5 Insignificant Significant Health/Haze

Odor Insignificant Major Quality

Type of Sensor FTIR UV OPL

Detector cooling Cryocooler - -

Path Length, m 400 150-1000 2000

Mode Monostatic Bistatic Monostatic

Compounds NH3, VOC*, CH4 NH3, H2S, Nox H2S or NH3

Scan frequency, Hz 1 1 4000

Detection Limits

Hydrogen sulfide Deuterium

ppm-m 10-30 0.4-5 6-25

ppb 75-600 2.8-33 3-120

Linear upper range

Ammonia Xenon

ppm-m 1.5 2 2

ppb 2-50 3-20 1-40

Linear upper range 903

Models BLS, TOM BLS, TOM BLS

Comparing Open Path Sensors

Type of Sensor FTIR UV OPL

Scanning Yes Yes ?

Reflectors -

200 m 30 cube Small retro

400 m 60 cube

1000 m 90 cube

Real-time quantification yes yes, w/ BLS yes

Capital cost 140K $20K-$45K $30K

Short term costs none none none

Annual costs Repump cooler, replace retros

New source None

Recalibration needs None Annually $7K laser/7 yr.

FTIR with 48-m Closed Cell Advantages

Measures greenhouse gases Measures ammonia: MDL=<6 ppb, NO, NO2

Measures dozens of other gases, SO2

Real-time measurement Quick response: limited by cell volume

Disadvantages Expensive: $75,000 Heavy, non-portable

Scanning FTIR - Tomography Layer house Horizontal scanning Vertical scanning

Source: Bruce Harris, U.S. EPA, 2004

Source: Bruce Harris, U.S. EPA, 2004

Field Measurement of Air Pollutants Near Swine Confined Animal Feeding Operations using UV DOAS and FTIR

C. D. Secrest (paper presented in 2000)

Ambient ammonia concentrations 0.8 km from a large swine facility with lagoons over a two week period were 0 to 900 ppb.

An Iowa Study Group recommended that ambient exposure to ammonia should not exceed 150 ppb.

The UV DOAS and FTIR were in good agreement. Open-path monitors combined with wind monitors are

powerful tools for comparing daytime and nighttime pollutant concentrations, and for determining the effect of wind speed on concentration.

S ourceW ind Di rect ion

FT IR on s c anne r

D ir ec tly m eas u r ed p lu m e c om ponen t

R e tr o re f lec to r s m oun ted abov e the g r ound

IR b eam ex ec u tin g a s ing le “ m on i to ring ev en t” (5 ev en ts m ak e up a com p le te “p lum e tr av e rs e ” )

G round m eas u red re tr o re flec to r s

M easuring a Fugitive Source w ith P lane Integrated O pen -Path Fourier T ransform In frared Spectrom eter

Source: Bruce Harris, U.S. EPA, 2004

Area sources -> diffuse plumes Open-path -> entire plume length An array paths maps the plume

Source: Bruce Harris, U.S. EPA, 2004

wind

OP-FTIR Measurement Pathsfor Path-Integrated Optical Remote Sensing (Tomography)

Controlled release simulation of an area source under unstable air conditions – worst case

Source: Bruce Harris, U.S. EPA, 2004

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght

[met

ers] Oxford 10/15/99: average flux - 1.12g/s

0.2

0.2

0.2

0.2

0.2

0.4

0.4

0.4

0.4

0.6

0.6

0.6

0.7

0.7

concentrations are in mg/m3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght

[met

ers] Oxford 10/15/99: Run #1 flux - 1.22g/s

0.1

0.1

0.1

0.1

0.10.1

0.3

0.3

0.3

0.3

0.3

0.4

0.4

0.4

0.4

0.5

0.5

0.5

concentrations are in mg/m 3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght

[met

ers]

Oxford 10/15/99: Run #2 flux - 1.15g/s

0.2

0.2

0.2

0.2

0.2

0.3

0.3

0.3

0.3

0.5

0.5

0.5

0.6

0.6

concentrations are in mg/m3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght

[met

ers]

Oxford 10/15/99: Run #3 flux - 1.01g/s

0.2

0.2

0.2

0.2

0.3 0.3

0.3

0.5

0.5

0.7

0.7

concentrations are in mg/m3

Hei

ght [

met

ers]

Reconstructed plumesActual release rate = 1.7 g/s

Calculated flux = 1.2 g/sMeasured σθ = 50.7°

Pasquill-Gifford Stability A - Unstable

Controlled release simulation of an area source under stable air conditions – best case

Source: Bruce Harris, U.S. EPA, 2004

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght [

met

ers]

Oxford 10/19/99: average flux - 1.45g/s

0.9 0.9

1.8

1.8

2.6

3.5

concentrations are in mg/m 3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght [

met

ers]

Oxford 10/19/99: Run #1 flux - 1.29g/s

0.9

0.9

1.9

1.9

2.83.8

concentrations are in mg/m 3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght [

met

ers]

Oxford 10/19/99: Run #2 flux - 1.6g/s

1.1

1.1

1.1

2.1

2.1

3.24.2

concentrations are in mg/m3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]H

eigh

t [m

eter

s]

Oxford 10/19/99: Run #3 flux - 1.49g/s

3.5

3.57

7

10.5

14

concentrations are in mg/m3

0 40 80 120 160 200 2402

6

10

14

Crosswind Distance [meters]

Hei

ght [

met

ers]

Oxford 10/19/99: Run #4 flux - 1.75g/s

1

1

2

2

2.93.9

concentrations are in mg/m3

Reconstructed plumesActual release rate = 1.7 g/s

Calculated flux = 1.5 g/sMeasured σθ = 12.7°

Pasquill-Gifford Stability C-D - Neutral

Source: Bruce Harris, U.S. EPA, 2004

FTIR ReferencesHarris, D. B., and E.L. Thompson, Jr. 1998. Evaluation of ammonia emission from

swine operations in North Carolina. Proc. Emission Inventory-Living in a Global Environment, VIP-88, pp. 420-429. AWMA, Pittsburgh, PA.

Harris, D. B., E.L. Thompson, Jr., D.A. Kirchgessner, J.W. Childers, M. Clayton, D.F. Natschke, W.J. Phillips. 1999. Multi-pollutant concentration mapping around a concentrated swine production facility using open-path FTIR spectrometry. Workshop on Atmospheric Nitrogen Compounds II: Emissions, Transport, Transformation, Deposition and Assessment, NCSU, Raleigh, NC, pp. 237-246.

Childers, J. W., E.L. Thompson, Jr., D.B. Harris, D.A. Kirchgessner, M. Clayton, D.A. Natschke, W.J. Phillips. 2001. Multi-pollutant measurements around a concentrated swine production facility using open-path spectrometry. Atm. Env. 35: 1023-1936.

Childers, J. W., Thompson, E. L., Jr., Harris, D. B., Kirchgessner, D. A., Clayton, M., Natschke, D. A., Phillips, W. J. (2001) Application of standardized quality control procedures to open-path fourier transform infrared data collected at a concentrated swine production facility. Env. Science & Tech. 35:1859-1866.

Source: Bruce Harris, U.S. EPA, 2004

FTIR ReferencesChilders, J. W., E.L. Thompson, Jr., D.B. Harris, D.A. Kirchgessner, M. Clayton, D.A.

Natschke, W.J. Phillips. 2000. Comparison of an innovative algorithm to classical least squares for analyzing open-path fourier transform infrared spectra collected at a concentrated swine production facility. Appl.Spect. 56:325-336.

Hashmonay, R. A., D.A. Natschke, K. Wagoner, D.B. Harris, E.L. Thompson, Jr., M.G. Yost. 2001. Field evaluation of a method for estimating gaseous fluxes from area sources using open-path fourier transform infrared. Env. Sci. Tech. 35:2309-2313.

Harris, D. B., E.L. Thompson, Jr., Vogel, C. A., Hashmonay, R. A., Natschke, D. A., Wagoner, K. Yost, M.G. Innovative approach for measuring ammonia and methane fluxes from a hog farm using open-path fourier transform infrared spectroscopy. 94th Annual Conf. of the AWMA, VIP-102-CD, AWMA, Pittsburgh, PA 2001.

Hashmonay, R.A. and D.B. Harris. 2001. Particulate matter measurements using open-path Fourier transform infrared spectroscopy. 94th Annual Conference of the Air & Waste Management Association, VIP-102-CD, AWMA, Pittsburgh, PA.

Harris, D.B., R.C. Shores, L.G. Jones. Ammonia Emission Factors from Swine Finishing Operations. Int. Emissions Inventory Conference, “One Atmosphere, One Inventory, Many Challenges.” www.epa.gov/ttn/chief/conferences/ei10/index.html.

0 0.2 0.4 0.6 0.8 1 1.2

Calculated Flux / Actual Flux

0

10

20

30

40

50

Hei

gh

t o

f o

bse

rvat

ion

s (m

) Notice that a complete flux measurement (flux sampling of plume to large height) overestimates the flux by ~ 10% (this is because of the neglect of turbulent flux)

15 m

5 m

25 m

C plume in neutral conditions along measurement plane

Flux measurement plane

Neutral Stability

Wind

Source: Lowry Harper USDA-ARS, 2004

ponds sheds

ponds

sheds

15 m

5 m

25 m

C plume in unstable conditions along measurement plane

Flux measurement plane

0 0.2 0.4 0.6 0.8 1 1.2

Calculated Flux / Actual Flux

0

10

20

30

40

50

Hei

gh

t o

f o

bse

rvat

ion

s (m

)

Notice that even if you go to z=50 m you don’t capture all the flux

Unstable (daytime)

Wind

Source: Lowry Harper USDA-ARS, 2004

Smearedplume

15 m

5 m

25 m

C plume in stable conditions along measurement plane

Flux measurement plane

0 0.2 0.4 0.6 0.8 1 1.2

Calculated Flux / Actual Flux

0

10

20

30

40

50

Hei

gh

t o

f o

bse

rvat

ion

s (m

)

Stable (nighttime)

Wind

Source: Lowry Harper USDA-ARS, 2004

Backward Lagrangian Stochastic (BLS) Dispersion Models

Backward Lagrangian Stochastic Modeling Introduced by Flesch, T.K., and J.D. Wilson.

1995. Backward-time Lagrangian stochastic dispersion models and their application to estimate gaseous emissions. J. Applied Meteorology 34:1320-1332.

Utilizes point or line measurement Ultrasonic or cup anemometers Flexible and easy to use. Surface layer model. Locate < 1 km. Commercial software available

www.thunderbeachscientific.com

UV-DOAS

Ultraviolet Differential Optical Absorption Spectroscopy

1-1000 ppb path length Fast scanning, compact, tunable EPA Equivalent Method for SO2, O3 and NO2. Also measures ammonia, benzene, toluene,

xylenes, styrene, Hg, HF, HNO2, HCHO Continuous operation MDL for ammonia = 2.8 to 5.8 ppb

Source: Myers, J., T. Kelly, C. Lawrie, and K. Riggs. 2000. ETV Technology Evaluation Report. Opsis, Inc. AR-500 Ultraviolet Open-Path

Monitor. ETV Advanced Monitoring Systems Center, Battelle.

EPA Lab for Ambient Measurements

UV-DOAS

UV-DOAS

UV-DOAS

TEOM

TEOM

METtower

1-min averaging andrecording intervals

Collocated UV’s

Source: Bruce Harris, U.S. EPA, 2004

Micromet Setup at Lagoons

FTIR & Tomography

UV & BLS

FTIR & BLS

Equipment Required per Team Two FTIR scanning systems with 20 retros Two UV systems Four computers for optical remote sensors One computer for data QAQC and analysis Two 3D ultrasonic anemometers (2 and 12 m) Complete weather station Two, 12-m towers for FTIR/UV systems One, 2 m tower for ultrasonic anemometer Software for computed tomography method Software for BLS method Van and trailer

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