| Odor emission from concentrated animal feeding operation (CAFOs) has become a public nuisance, which causes serious obstacles to sustainable development of animal husbandry. Research on characteristics and change patterns of odor emission from CAFOs is the theoretical basis of odor control mechanisms. This was the first time to carry out odor emission measurement and simulate odor dispersion using atmospheric dispersion model in China. As the preliminary investigation on monitoring and assessment of odor emission from CAFOs in China, it could provide theoretical and technical basis for odor pollution control and assessment techniques of animal production.This thesis did primary research on odor emission charactoristics, dispersion modeling and odor emission reduction from pig buildings and composting facility as follows,1. Odor concentration was measured by Three Odor Bag Method in experimental finishing pig rooms with four types of floor systems. Diunal variation of odor concentration, odor emission factors were studied in the research. It showed that there were significantly positive correlations between odor concentration and temperature, pig weight (p<0.05). The correlation was not significantly between odor concentration and relative humidity (p>0.1). Significant differences were found in the four pig rooms with different floor systems (p<0.05). In summer, odor concentration was highest in the pig room with traditional concrete floor system, the second was for full-slatted floor system, and the third was for half-slatted floor system. In winter, odor concentration was highest in the pig room with half-slatted floor system, the second was for concrete floor system, and the third was for full-slatted floor system. Odor concentration was lowest in the pig room with deep-litter fermentation system in two seasons. The results indicated that deep-litter system was effective for odor mitigation. Odor emission factors from the deep-litter room, half-slatted floor room, fully-slatted floor room, and concrete floor room were 3.03±2.35,3.71±2.20,4.03±1.57,4.84±2.26 OU/m2/s, respectively.2. The effect on odor emission reduction and Nitrogen (N) reservation of 2%(w/v) H2SO4 spraying on compost materials in composting facility with mechanically ventilation was studied. It showed that H2SO4 spraying was effective to Odor emission reduction and N reservation. Odor concentration, NH3 concentration, N loss,NH3-N loss and NH3 commulative emission rate were reduced by 60.8%,41.8%,31.0%,63.4%,63.1%, respectively.3. Odor emission factors from growing-finishing pig rooms in extensive pig farm were studies and compared with odor emission datas from experimental growing-finshing pig rooms. Odor emission rate from nursery pig room, finishing pig room, gestating pig room and farrowing pig room were 1.05,2.71,3.92,10.15 OU/pig/s. It was estimated that total odor emission factor from the intensive pig farm was 32391.1 OU/s(0.6478 OU/m2/s)without consideration of odor emission from composting facility and lagoon.4. Based on odor emission factor from the extensive pig farm, odor dispersion was modeled with software of Aermod System 2.2. It was concluded that the predicted daily mean odor concentration> 5 OU/m3 of four villages were accounted for 45.3%,35.7%,9.7%,10.1%, respectively. As composting facility and lagoon were not considered, the total odor emission rater was relatively low, resulting in lower predicted value. After calibrated with the scaling factor of 47.3, Laotang village's annual odor concentration was 7.75 OU/m3. Therefore, the influence of pig farm on the surrounding residents should not be neglected.
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