Workshop on Agricultural Air Quality Evaluation of Zeolite for Control of Odorants Emissions from Simulated Poultry Manure Storage

Poultry feeding operations are associated with aerial emissions of ammonia (NH3), volatile organic compounds (VOCs), and odor, and the magnitude of emissions is influenced by manure management practices. As a manure treatment additive, zeolites have been shown to have the potential to control NH3. Because of their properties it is also expected that zeolites could effectively adsorb VOCs and odor. In this controlled laboratory study involving simulated poultry manure storage, the effectiveness of zeolite in controlling odor and VOCs was evaluated. In the first 2 trials zeolite was topically applied on fresh poultry manure from egg layers at the rates of 0, 2.5%, 5 % or 10 % (by weight). In the third trial, zeolite was applied in layers over fresh manure. Headspace samples from the emission vessels were collected with solid phase microextraction (SPME) and analyzed on a multidimensional-gas chromatograph-mass spectrometer-olfactometry (MDGC-MS-O) system for identification and prioritization of poultry manure odorants (Figure 1). Acetic acid, butanoic acid, isovaleric acid, indole and skatole were consistently controlled, with the reduction rate being proportional to the zeolite application rate. Dimethyl trisulfide and phenol were consistently generated, and with a few exceptions, the rate of generation was proportional to the application rate. Average reduction of the total odor was 67 % (±12%) and 51 % (±26%) for the two topical applications, respectively, while no significant reduction of VOCs and odor was found for the layered application