The objective of this experiment was to evaluate the effect of Chamaecyparis obtus extract to reduce odor emissions released from the swine feeding operations. Finisher pigs [Landrace × (Yorkshire × Duroc)] with an initial body weight averaging 50 kg were housed separately in two rooms with eighty eight pigs in each room at a swine feeding operation site. C. obtus extract was sprayed in the room by ceiling sprayer for one minute at twice per day during two months. Concentrations of odorous compounds from air in the room of the swine feeding operation were analyzed at four times during two months. Levels of butyric acid, valeric acid, i-butyric acid, ivaleric acid, skatole, methylmercaptan, and trimethylamine tended to decrease in C. obtus extract spray treatment group compared to the non-spray treatment group (P > 0.05). Odor activity values of butyric acid, valeric acid, skatole and trimethylamine were higher than other odorous compounds and decreased by 72%, 76%, 54% and 20%, respectively, in C. obtus extract spray treatment group compared to the non-spray group. Taken together, C. obtus extract showed an odor reducing capability in the air of a swine feeding operation suggesting that it possesses anti-bacterial properties as well as having a dust removal and masking effect.

In this study, odor active compounds, emitted from food waste composting facility, were analyzed and their contribution degree were evaluated. Sample gases were collected at the inlet and outlet of scrubbing tower and bio-filter, respectively. The odor active compounds were separated by GC/FID/Olfactometry (GC/FID/O) and identified by GC/MS. Odor intensity and SNIF (Surface of Nasal Impact frequency) were used to evaluate contribution of each odor active compound. It was possible to calculate contribution rate (%) and reduction rate (%) of odor active compounds using analysis and evaluation of contribution degree of odor active compounds. As a result, the compounds showing the high contribution degree were fatty acids, ketones at inlet and aldehydes, ketones at outlet. Deodoring equipment of food waste composting facility appeared effective for the reduction of aldehydes, ketones but appeared week for the reduction of aldehydes. Although scrubbing tower and bio-filter could reduce 7 times of odor level, the outlet gases had odor dillution ratio of 3000, which exceed the allowable levels of Korean guideline by 6 times.