Laor, Y., Agricultural Research Organization, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Ravid, U., Agricultural Research Organization, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Armon, R., Faculty of Civil and Environmental Engineering, Technion, Haifa, Israel
Saadi, I., Agricultural Research Organization, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Ozer, Y., Agricultural Research Organization, Newe Ya'ar Research Center, Ramat Yishay 30095, Israel
Koziel, J.A., Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, United States
Yang, X., Department of Agricultural and Biosystems Engineering, Iowa State University, Ames, IA, United States

Advanced oxidation technologies such as various combinations of UV/TiO 2/O3 have the potential to decompose multiple odorous volatile organic compounds (VOCs). Only limited work has been devoted to investigate the potential of these methods to treat real odors emitted from various agricultural and industrial sources. The present study explores the effectiveness of UV-TiO2 photocatalysis to treat the odors associated with poultry manure. A dynamic (flow-through) setup was built in which the odor source was obtained by purging fresh or aged suspension of poultry manure. The photoreactor was constructed out of a 2.5-liters quartz tube which was surrounded by a ring of 24 individually controlled 18W "black light" lamps (365 nm). A TiO2-coated support was placed inside the reactor. The effectiveness of the various treatments was assessed by analyzing specific odorants (using headspace solid phase microextraction followed by GC-MS) and collecting the total air in Tedlar bags for odor analysis by dynamic olfactometry. Ammonia was measured with Kitagawa color tubes. Samples were withdrawn through ports before and after the photoreactor, and the effectiveness of treatments was assessed as percent removal for each target compound based on peak area counts obtained for separate VOCs or concentrations of ammonia obtained by the color tubes. Experiments were designed to examine the effect of flow rates (i.e. residence time), number of lamps in use (i.e. energy dose), and the role of TiO2. Removals of key manure-associated odorants, such as dimethyl disulfide, dimethyl trisulfide and p-cresol, were between 80 to ∼100% (decreased to below detection limit). The total odor was reduced by 75% in one experiment with fresh manure suspension (starting from about 70,000 odor units, OU) and was not reduced much in another experiment with aged manure suspension (starting from about 700 OU) The latter was presumably due to the contribution of odor from trace levels of ozone which was generated under the photo catalytic conditions. Ammonia was reduced between 0-50% in the various treatments. The reported removals were obtained for residence times ranging from only a few and up to a maximum of about 10 seconds. After optimization, this approach may become applicable for the treatment of outflow air at mechanically-ventilated barns. Copyright ©2010, AIDIC Servizi S.r.l.