References of "Calvet, S"
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See detailOdour evaluation of a dairy farm with anaerobic digestion
Ubeda, Yolanda; Neyrinck, Roland ULg; Calvet, S. et al

Conference (2010, September)

The present work focuses on odour evaluation of a dairy farm with anaerobic digestion, located in the Luxembourg province (Belgium). This study pursues three main goals: 1.- To evaluate the effect of the ... [more ▼]

The present work focuses on odour evaluation of a dairy farm with anaerobic digestion, located in the Luxembourg province (Belgium). This study pursues three main goals: 1.- To evaluate the effect of the anaerobic digestion process on the odour level in the farm, 2.- To compare field and laboratory odour measurement techniques and 3.-To study the influence of the meteorological observation frequency on the odour plume, through the use of dispersion models. Three different approaches were used to characterize the odour: dynamic and field olfactometry and sniffing team method. Odour emissions from all sources were measured by duplicated through dynamic chamber and olfactometric analysis in two different situations: in normal conditions and after stirring the odour source. Two odour field measurement campaigns were conduced in the surroundings of the farm, and meteorological conditions were recorded two times per minute with a weather station. After comparing odour emissions with field measurements through dispersion modeling, we concluded that the best results were obtained using minimum and averaged odour emission rates. Emission rates measured in stirring conditions overestimated the reach of odour perceived in the field in three field campaigns. Overall odour emitted from the farm increased with the anaerobic digestion process. Although odour emission from digested manure is reduced in comparison with non-treated manure, the presence of agricultural wastes increases global odour emission. Finally, meteorological data were averaged each one, five and fifteen minutes. Odour shape was thinner and more extended with 15-minutes data, whereas it was larger and shorter with 30-secondes records. One minute and 5-minute values showed intermediate situations. In conclusion, different techniques to measure odours were compared in this study and, according to the results, field techniques seemed to be more realistic than dynamic olfactometry. [less ▲]

Detailed reference viewed: 97 (19 ULg)
Peer Reviewed
See detailPreliminary study of effects of anaerobic digestion of manure on VFA content and Odor concentration
Ubeda, Yolanda; Nicolas, Jacques ULg; Calvet, S. et al

Conference (2010, September)

In this study, the potential reduction of odor of anaerobic digestion has been evaluated in three commercial facilities located in Belgium, Luxembourg and Germany. Odor concentrations were measured by ... [more ▼]

In this study, the potential reduction of odor of anaerobic digestion has been evaluated in three commercial facilities located in Belgium, Luxembourg and Germany. Odor concentrations were measured by olfactometric analyses in two different situations: at normal conditions and after the stirring the odor source. Parallel to these measures, representative samples were taken for digested and untreated manure and other co-substrates present in the facilities. Volatile solids, total solids, total suspended solids, volatile suspended solids, soluble chemical oxygen demand, ammonia nitrogen, total kjeldhal nitrogen, volatile fatty acids, and pH were determined in laboratory. The performance of anaerobic digestion in terms of VFA concentration reduction achieved values of 77-96%. Odor concentration was reduced by anaerobic digestion in the two studied scenarios: at normal conditions and after the stirring the odor source. No significant effect of anaerobic digestion on chemical analyses was observed, except for an increase in the ammonia nitrogen content. Significant correlations were found between the logarithm of odor concentration and different odor compounds (VFA, acetic, butyric, isobutyric, isovaleric). Correlations between odor concentration, VFA and other parameters (VS, VSS and pH) were also obtained. These results confirm that anaerobic digestion may reduce odor annoyance potential and VFA concentrations. In addition, odor concentration seems to be related with other chemical parameters, therefore more research is needed to obtain further conclusions. [less ▲]

Detailed reference viewed: 81 (16 ULg)
Peer Reviewed
See detailEvaluation of odour impact from a landfill area and a waste treatment facility through the application of two atmospheric dispersion models.
Ubeda, Yolanda; Ferrer, M.; Sanchis, E. et al

Conference (2010, July)

Odour emission from landfill areas has a high potential to cause significant annoyance to people living in their surroundings. In order to avoid odour nuisance, it is crucial to select the best location ... [more ▼]

Odour emission from landfill areas has a high potential to cause significant annoyance to people living in their surroundings. In order to avoid odour nuisance, it is crucial to select the best location in the project phase of these facilities. In the present work, two different atmospheric dispersion models were employed to predict odour impact from a projected landfill area and a waste treatment facility. The first model used was a simplified Gaussian Atmospheric Dispersion model developed by the authors. Calculated odour concentrations were represented using GIS tools (Esri ®ArcMapTM software). Regarding to the second model, it was a commercial bi-Gaussian Atmospheric Dispersion one. The odour impact of the waste treatment facility is expected to be low, because of the high efficiency of air biofiltration treatments and the dispersion effect of the stack. The shape and the reach of odour percentile contours were quite similar, providing coherent results between two models. Concerning the landfill installation, odour concentrations were modelled for the prevailing winds. The results obtained with both models differ in the reach of odour. The maximum distance obtained by the simple dispersion model was 1.5 km, compared with the almost 5 km modelled by the commercial bi-Gaussian one. The reasons of this disparity could be caused by the difference in the dispersion coefficients employed in the two models and also an error related to ground level emission. In addition, the meteorological conditions in the Mediterranean typically present a high proportion of calm winds, which provided worse dispersion results and did not reflect the real odour dispersion. Odour emission rate seems to be overestimated, and this could explain the high distance reached by odour. Field measurements are required when landfill installation becomes operational, in order to determine the real impact of odour. Bi-Gaussian Dispersion Models may not be appropriate to quantify the odour impact from agricultural sources. [less ▲]

Detailed reference viewed: 97 (4 ULg)