Use of AERMOD to Determine a Hydrogen Sulfide Emission Factor for Swine Operations by Inverse Modeling

Details

• Personal Author:
  Altmaier R ; O'Shaughnessy PT
• Description:
  This study was conducted to determine both optimal settings applied to the plume dispersion model, AERMOD, and a scalable emission factor for accurately determining the spatial distribution of hydrogen sulfide concentrations in the vicinity of swine concentrated animal feeding operations (CAFOs). These operations emit hydrogen sulfide from both housing structures and waste lagoons. With ambient measurements made at 4 stations within 1 km of large swine CAFOs in Iowa, an inverse-modeling approach applied to AERMOD was used to determine hydrogen sulfide emission rates. CAFO buildings were treated as volume sources whereas nearby lagoons were modeled as area sources. The robust highest concentration (RHC), calculated for both measured and modeled concentrations, was used as the metric for adjusting the emission rate until the ratio of the two RHC levels was unity. Utilizing this approach, an average emission flux rate of 0.57 microg m-2 s-1 was determined for swine CAFO lagoons. Using the average total animal weight (kg) of each CAFO, an average emission factor of 6.06 x 10-7 microg yr-1 m-2 kg-1 was calculated. From studies that measured either building or lagoon emission flux rates, building fluxes, on a floor area basis, were considered equal to lagoon flux rates. The emission factor was applied to all CAFOs surrounding the original 4 sites and surrounding an additional 6 sites in Iowa, producing an average modeled-to-measured RHC ratio of 1.24. When the emission factor was applied to AERMOD to simulate the spatial distribution of hydrogen sulfide around a hypothetical large swine CAFO (1 M kg), concentrations within 0.5 km from the CAFO exceeded 25 ppb and dropped to 2 ppb within 6 km of the CAFO. These values compare to a level of 30 ppb that has been determined by the State of Iowa as a threshold level for ambient hydrogen sulfide levels. [Description provided by NIOSH]
• Subjects:
  Agriculture Air Pollutants, Occupational Air Pollution Animal Husbandry Animals Environmental Exposure Hazardous Substances Hazardous Waste Occupational Health Safety
• Keywords:
  AERMOD Agricultural Industry Agricultural Safety Agricultural Workers Airborne Particles Air Quality Measurement Air Quality Monitoring Analytical Models Animal Husbandry Animal Husbandry Workers Animal Waste Atmosphere Analyzers Author Keywords: Inverse Modeling Confinement Buildings Detectors Dispersion Emission Factor Emission Sources Exposure Levels Gas Detectors Gas Indicators Hazardous Waste Hydrogen Sulfide Models Toxic Gases

  More +
• ISSN:
  1352-2310
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Iowa ; OSHA Region 7
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  45
• Issue:
  27
• NIOSHTIC Number:
  nn:20061934
• Citation:
  Atmos Environ 2011 Sep; 45(27):4617-4625
• Contact Point Address:
  Patrick T. O'Shaughnessy, Department of Occupational and Environmental Health, The University of Iowa, UI Research Park, IREH, Iowa City, IA 52242, USA
• Email:
  patrick-oshaughnessy@uiowa.edu
• CAS Registry Number:
  Hydrogen sulfide (CAS RN 7783-06-4)
• Federal Fiscal Year:
  2011
• Performing Organization:
  University of Iowa
• Peer Reviewed:
  True
• Start Date:
  20050701
• Source Full Name:
  Atmospheric Environment
• End Date:
  20290630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:12615b8dd736875413088b7b9c39d8c532488eb1bf8b5536034276c3e2d7ef953e7ffea4df12d5e15e89547a56c80da71e75626be7a3c38468279951e79888ff
• Download URL:
  https://stacks.cdc.gov/view/cdc/225273/cdc_225273_DS1.pdf
• File Type:
  [PDF - 620.97 KB ]