Submitted to: Proceedings of American Society of Agricultural Engineers
Publication Type: Proceedings
Publication Acceptance Date: 7/20/2005
Publication Date: 7/20/2005
Citation: Koziel, J.A., Cai, L., Hoff, S., Xin, H., Wright, D.D., Trabue, S.L. 2005. Analysis of gases and odors associated with particulate matter in swine barns using SPME-GC-MS-Olfactometry. Proceedings of American Society of Agricultural Engineers Annual International Meeting, July 17-20, 2005, Tampa, Florida. Paper No. 050448. Interpretive Summary: Volatile and semi-volatile compounds in the vapor phase and sorbed to particulate matter (PM) are emitted from swine production facilities daily. To date, little is known on the types of compounds that are associated with PM. In this research, we characterize the volatile and semi-volatile compounds associated with various size fractions of PM from a swine finishing barn. The ambient particulate mass concentration of PM-10 (10 micrometer), PM-2.5 (2.5 micrometer), PM-1 (1 micrometer) and TSP (total suspended particulate matter) were collected continuously over a 24 hour periods using a TEOM 1400a monitor in November 2004. A total of 7 sets of filters were collected for each size fraction. Filters for TSP and various PM were collected and preserved using sealed 40 mL vials and transported to Atmospheric Air Quality Laboratory at Iowa State University. A method was developed to extract the gases/odors from TSP and PM filters using solid phase microextraction (SPME). Several SPME coatings, SPME fiber exposure times, and temperature were initially tested. The optimum method used a Carboxen/PDMS (polydimethylsiloxane) 85 micrometer SPME coated fiber with a 3 hr exposure time at 25oC. Gases and odors were extracted from each TSP and PM filter following the SPME method and analyzed on a gas chromatography-mass spectrometry-olfactometry (GC-MS-O) system. This instrument was used to determine chemical composition of gases adsorbed/absorbed to TSP and PM filters. Simultaneously to chemical analysis, the odor character and intensity associated with each PM filter was also determined on GC-MS-O instrument. More than 50 compounds were identified in swine PM including H2S, mercaptans, amines, ketones, aldehydes, alkanes, VFAs (volatile fatty acids), phenolics, and indolic compounds. This approach allowed for identification of several odor-defining swine compounds in TSP and various PM size fractions, and demonstrates the need to control swine dust to lower odor emitted from production facilities. Research results described in this report provides agricultural scientists and engineers methodology and data for determining the dominate odorants associated with various size fractions of particultate matter from swine production operations.
Technical Abstract: Gases, odors and particulate matter (PM) are emitted from swine barns. To date, little is known on the interactions between gases, odors, and PM. In this research, we measured concentrations of PM in a swine finish barn in Iowa using three collocated continuous TEOM 1400a monitors in November 2004. Four size ranges were measured, i.e. total suspended particulate (TSP), PM-10, PM-2.5, and PM-1, each lasting 24 hr at a time. The total of 7 sets of filters were collected. Used TSP and PM filters were collected and preserved in enclosed 40 mL vials and transported to Atmospheric Air Quality Laboratory at Iowa State University. A new method was developed to optimize extraction of gases and odors from dust filters using solid phase microextraction (SPME). Several SPME coatings and sampling/extraction times were initially tested. The Carboxen/PDMS 85 micrometer SPME coating, 3 hr extraction time at 25oC were then used to extract VOCs and odors from all 7 sets of filters. Gases and odors were extracted from the vial headspace and a gas chromatography-mass spectrometry-olfactometry (GC-MS-O) system was used to determine chemical composition of gases adsorbed/absorbed to PM. More than 50 compounds were identified in swine PM including H2S, mercaptans, amines, ketones, aldehydes, alkanes, VFAs, phenolics, and indolics. Simultaneously to chemical analysis, the odor character and intensity associated with PM was also determined on GC-MS-O. This approach allowed for identification of several of odor-defining swine odorants in dust. Work continues to quantify VOCs and correlate them with measured PM concentrations and measured odor intensity. Swine dust appears to be very important carrier of many key swine odorants. Control of swine dust has a great potential to simultaneously control odor.