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Odors due to malodorous gas and vapor emissions from units of Izmir Wastewater Treatment Plant (WWTP) were studied and evaluated with respect to chemical composition. Altogether 29 target compounds consisting of 4 different groups of chemicals were identified and quantified in the odorous gas samples from wastewater and sludges. Total volatile malodorous organic compounds (VMOC) consisted of reduced sulfur compounds (RSCs) and different volatile organic compounds (VOCs) including volatile organic compounds (VOCs), aldehydes, monoaromatics (BTX) and some halogenated organics. Among these components the most abundant group was the monoaromatics (69% of the total VOC). A statistically significant linear relationship was found between odor concentrations determined by olfactometry and total VOC concentrations (r2 = 0.89, n = 5, P < 0.05) in the samples of odorous gases. Based on the odor contribution ratios of the compounds studied, the results of the study revealed that hydrogen sulfide, propanal and toluene were dominating in the odor emissions and these were explaining 99% of the variability in odor concentrations (r2 = 0.99, n = 5, P < 0.05). It was shown that not only the hydrogen sulfide and RSCs but also other organics were important in forming the odors from sludge units and sludge management areas. [ABSTRACT FROM AUTHOR]

The article discusses a study in odor determination at wastewater collection systems. This paper focuses on the differentiation of olfactory and hydrogen sulfide analysis. Sampling and measurement of hydrogen sulfide in assessing nuisance odors in wastewater handling systems are studied. Results in concentrations and the perception of public in odor from wastewater collection and treatment systems are further studied for statistical relationships between analytical and sensory odor in hydrogen sulfide concentrations.

Odor levels around a meat packaging and rendering plant were predicted by using the CALPUFF dispersion model. The product of olfactometrically measured odor concentration and volumetric flow rate of the stack gas stream was used as emission strength of the source. Ambient odor levels were also measured at two sites downwind of the plant by olfactometry. This was possible, as odor concentrations were above 50 odor units per cubic meter (OU m −3 ), and this means that the concentrations were always exceeding the minimum 10 OU m−3 that can be safely measured by this technique. Odor samples were taken consecutively at two sites downwind of the source with 10 s duration each. These sampling sites were chosen so that they had continuous odor nuisance problems, which indicated that they were near the centerline of the plume. Between samples 10-s intervals were necessary to prepare the sampler for the next sampling bag connection. The overall sampling period was 10 min each at the two sites. Meteorological measurements were carried out throughout the odor sampling process at the sites. Wind direction and speeds were recorded at the end of each sampling and used in predictions made using the model. Predicted results were compared with the odor measurements carried out on the samples. Measured and predicted odor concentrations were tested to see the degree of correlation. The measured and predicted results at such very short averaging times correlated well, with a good agreement between the two series. [ABSTRACT FROM AUTHOR]

Daily average SO2 concentrations were measured during August 1999–September 2000 period in the mountains around Izmir. Sampling devices to collect integrated daily SO2 samples were located at four different sites. These sites were Yamanlar Mountain in the north, Tekketepe height of Karabelen Mountain in the south, and two mountain villages (Kiziluzum and Bespinar) located east of Izmir. Samples were analyzed by using standard methods. Maximum daily SO2 concentrations up to 433 μg m-3 were found with the average values ranging between 75–135 μg m-3 per day at the four mountain stations. Annual mean values were above the threshold levels acceptable for the health of trees. It is concluded that such high SO2 pollution might have caused the noted decline in the forests. In order to decide the sources of such high levels of pollution on the forested mountains, trajectory analyses were carried out. Results obtained at Tekketepe station are given in this article and they point to the fractional contributions of dense industrial areas around Izmir, to the forested heights of Tekketepe. Local topography and location of industrial zones around the city are seen to have a strong effect on the deteriorated air quality over the mountains. The annual and seasonal averages and ten maximum daily measurements at the Tekketepe sampling site indicate that the highest contribution to the deterioration of air quality is associated with the northerly wind sectors. [ABSTRACT FROM AUTHOR]