albert j. heber, associate professor director, purdue agricultural air quality lab
DESCRIPTION
Building Environment Research & Education. Albert J. Heber, Associate Professor Director, Purdue Agricultural Air Quality Lab. AgAirQuality.com. Agricultural and Biological Engineering Purdue University. “A Buoyant Convective Flux Chamber for Measuring Liquid Surface Emissions”. - PowerPoint PPT PresentationTRANSCRIPT
Albert J. Heber, Associate ProfessorDirector, Purdue Agricultural Air Quality Lab
Agricultural and Biological Engineering
Purdue University
Building EnvironmentResearch & Education
AgAirQuality.com
“A Buoyant Convective Flux Chamber for Measuring Liquid Surface Emissions”
hoodsunny
A.J. Heber, T.T. Lim, J.Q. Ni and K.J. Fakhoury
AgAirQuality.com
Objectives Develop floating emission chamber Evaluate performance
Field Tests
Lab Tests
Air Supply Unit
Blower Adsorbent
Filter
Air Supply Blower
198 m3/h
(117 cfm)
Air Supply Unit
Air Supply Filter
22.4 kg of adsorbent Charcoal Permanganate Zeolite
Top View
Air outlet
Sampling location
Air velocity probe
Stainless steel
divider
Air inlet
Styrofoam boards for buoyancy
Liquid surface area = 0.76 m2
BCFC Inlet
Stainless Steel Lining
“Hairpin” Airflow Path
2.4 m path length
2.2 sec residence
time
1.1 m/sSampling location
Air velocity probe
Air outlet
Side View
Air inlet
End View
Air Inlet
Air Outlet
Divider31 cm
Samplingpoint
Lab Tests
N-butanol at 250-20,250 ppm in 200 L water
Odor emission only.Lagoon effluent: 100, 50 and 25% dilution
H2S, NH3, CO2 and odor emission.
Gas Analyzers Ammonia (0 to 200 ppm)
• Ammonia converted to nitric oxide with a SS converter, 875 C
• Chemiluminescense: PMT detects light emission from reaction of nitric oxide with ozone.
• Sample flow rate = 0.5 Lpm Hydrogen sulfide (0 to 10,000 ppb)
• Hydrogen sulfide converted to sulfur dioxide, SO2
• Pulsed fluorescence: PMT detects UV from decaying SO2 molecules
• Sample flow rate = 1.0 Lpm Carbon dioxide (0 to 5,000 ppm)
• Photoacoustic infrared sensor • Sample flow rate = 1.0 Lpm.
Instrumentation Room
Manifolds
PC
Gas sensors
Odor Threshold Measurement
1 of 8 panelists
Olfactometer
Tedlar bag
Panel leader’s hand
PC
N-Butanol Test Results
Blank: 9 OU Inlet mean: 10.4 OU (8 to 13 OU) Odor emission: 0.5 to 11.2 OU/s-m2
Emission Rate of N-Butanol
Emission Rate = 5.10 Log(C) - 13.05
R2 = 0.82
0
4
8
12
100 1000 10000 100000Concentration of N-butanol in Tank, ppm
Em
issi
on R
ate,
OU
/s-m
2
2027
5163
155
Lagoon Effluent Test Results
Inlet mean: 22 OU Outlet mean: 27 OU Odor emission: 0.8 OU/s-m2 at 100% Hydrogen sulfide too low to measure Inlet ammonia mean: 1.8 ppm Outlet ammonia mean: 2.9 ppm Ammonia emission proportional to
effluent concentration. Ammonia levels below odor threshold
Lagoon Effluent: NH3 Emission
Emission Rate = 4.15x - 18.1
R2 = 0.90
0
100
200
300
400
0 20 40 60 80 100 120Lagoon Effluent Dilution, %
Em
issi
on R
ate,
mg/
hr-
m2
Solids: 0.16%
Field Tests
Swine grow-finish facility Four consecutive days Day 1: Effect of air speed
crustincorner
Anaerobic Treatment Lagoons
2nd Stage Basin
1st Stage Basin
Six Swine Buildings
Deployment
Odor Emission Tests
hoodwtwovacs
3 Lpm
pumpsAir
velocity control
Hammer
Evacuation chamber
Raceway(6 m)
Chamber Inlet and Outlet Samples
hebervacus
Emission vs. Air Speed
Emission = 1.85 x 0.93
R2 = 0.88
0
1
2
3
4
0.0 0.5 1.0 1.5 2.0
Surface Air Speed, m/s
Measured Predicted
Emission, OU/m2-s
Field Test Results
Inlet mean: 23 OU (12 to 42 OU) Outlet mean: 52 OU Odor emission: 1.5 to 2.1 OU/s-m2
Mean of 1.7 OU/s-m2 corresponded to 1,000 ppm n-butanol.
Advantages
Large air filtration and cleaning unit Inlet air sampling Large liquid surface area Long air path
Disadvantages
Size (van or pickup required) Weight (2-4 people required) Gentle berm slopes required, >3:1 Limited reach (five meters)
Future Research
Reduce size and weight Evaluate and improve internal air profiles Study effect of flow rate on emission
Conclusions
Good comparative measurements of gas and odor emission rates
Conclusions
Low sampling variance
Conclusions
Lower detection limit: 500-1000 ppm n-butanol.
ConclusionsLower limit reached with
properly designed swine lagoon
0.16% solids
“Low odor” lagoon
Conclusions
hood5-7
Odor emission rate increased for 1000-20,000 ppm n-butanol
Acknowledgements
Purdue University Agricultural Research Program
State of Indiana Value Added Research Program Ramco Sales, Inc.
Questions?
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