title: Performance of commercial nonmethane hydrocarbon analyzers in monitoring oxygenated volatile organic compounds emitted from animal feeding operations.
abstract: Quantifying non-methane hydrocarbons (NMHC) from animal feeding operations (AFOs) is challenging due to the broad spectrum of compounds and the polar nature of the most abundant compounds. The purpose of this study was to determine the performance of commercial NMHC analyzers for measuring volatile organic compounds (VOCs) commonly emitted from AFOs. Three different NMHC analyzers were tested for response to laboratory generated VOCs, and two were tested in the field at a commercial poultry facility. The NMHC analyzers tested included gas chromatography/flame ionization detector (GC/FID), photoacoustic infrared (PA-IR) and photoionization detector (PID). The GC/FID NHHC analyzer was linear in response to nonpolar compounds, but detector response to polar oxygenated compounds were lower than expected due to poor peak shape on the column. The PA-IR NMHC instrument responded well to the calibration standard (propane), methanol, and acetone, but it performed poorly with larger alcohols and ketones and acetonitrile. The PA-IR response varied between compounds in similar compound classes. The PID responded poorly to many of the most abundant VOCs at AFOs, and it underreported alcohols by > 70%. In the field monitoring study, total NMHC concentrations were calculated from sum total of VOC determined using EPA Methods TO-15 and TO-17 with GC-MS compared to results from NMHC analyzers. NMHC GC/FID values were greater than the values calculated from the individual compound measurements. This indicated the presence of small hydrocarbons not measured with TO-15 or TO-17 such as propane. The PA-IR response was variable, but it was always lower than the GC/FID response. Results suggest that improved approaches are needed to accurately determine the VOC profile and NMHC emission rates from AFOs.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, National Laboratory for Agriculture and the Environment, Ames, Iowa 50011, USA. steven.trabue@ars.usda.gov
authors.forename: Steven
authors.initials: S
authors.lastname: Trabue
authors.forename: Kenwood
authors.initials: K
authors.lastname: Scoggin
authors.forename: Laura L
authors.initials: LL
authors.lastname: McConnell
authors.forename: Hong
authors.initials: H
authors.lastname: Li
authors.forename: Andrew
authors.initials: A
authors.lastname: Turner
authors.forename: Robert
authors.initials: R
authors.lastname: Burns
authors.forename: Hongwei
authors.initials: H
authors.lastname: Xin
authors.forename: Richard S
authors.initials: RS
authors.lastname: Gates
authors.forename: Alam
authors.initials: A
authors.lastname: Hasson
authors.forename: Segun
authors.initials: S
authors.lastname: Ogunjemiyo
authors.forename: Ronaldo
authors.initials: R
authors.lastname: Maghirang
authors.forename: Jerry
authors.initials: J
authors.lastname: Hatfield
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D000822:Animal Husbandry; D000818:Animals; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D006799:Housing, Animal; D006838:Hydrocarbons / Q000737:chemistry*; D055549:Volatile Organic Compounds / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D006838:Hydrocarbons; D055549:Volatile Organic Compounds