In this study, hybrid devices were developed to simultaneously remove odor and particulate matter (PM) emitted during meat grilling, and their performance was evaluated. A ceramic filter system and surfactant microbubble plasma system were used to reduce particulate matter. For odor reduction, an electro-oxidation system, an ozone-active catalytic oxidation system, and a multi-adsorption filter system were used. By combining the above particulate matter reduction and odor reduction devices, the reduction efficiency of odor and particulate matter generated during meat grilling was analyzed. As a result, most of the six combined device conditions showed a reduction efficiency of more than 90% for particulate matter. The combined odor also showed a high reduction efficiency of less than 200 times the emission concentration standard. This study also evaluated 22 types of odorous substances, of which ammonia (NH3) and hydrogen sulfide (H2S) showed removal efficiencies of more than 99%. Therefore, it is expected that the combination of these technologies can be used and applied directly to the sites where meat grilling restaurants are located to effectively contribute to the simultaneous reduction of particulate matter and odor.
Four types of metal oxide semiconductor gas sensor arrays were used to observe the aroma and spoilage odor emitted during the ripening process of plum & banana fruits. All gas sensors showed a high correlation (R=0.82~0.90) with the olfactory. The TGS 2603 sensor showed a high correlation of 0.90 between the odor generated and sensory perception of smell in the process of ripening and decaying fruits. In addition, it showed a very high correlation of 0.91 with the decay rate of the plum sample, and the significance probability through one-way ANOVA was also less than 0.05, which confirmed it as an optimal gas sensor (TGS 2603). Principal component analysis was performed using all the data. The cumulative variability was 99.54%, which could be explained only by two principal components, and the first principal component was 95.11%, which was related to the freshness of the fruit. It was analyzed as fresh fruit in the negative(-) direction and decayed fruit in the positive(+) direction.
In this study, actual odor conditions were investigated in restaurants, livestock facilities, and major odor discharge facilities around daily life, and an odor modeling program was performed to find ways to improve odors in odor discharge facilities. The odor modeling results of restaurants around daily life showed that the complex odor concentration of large restaurants, which are close to residential areas, is higher than the acceptable complex odor standard at the receiving point. It was judged that a plan to increase the height of the restaurant odor outlets and a plan to reduce the amount of odor discharge was necessary. As a result of modeling the life odor of livestock housing facilities, when the distance from the housing facility is far away, the actual emission concentration is much lower than the acceptable emission concentration at the receiving point. It was judged that such facilities need to be reviewed for ways to reduce the emission of odorous substances, such as sealing the livestock housing facilities or improving the livestock environment. The main odor emission business sites that show complex odor concentration as 1,000 times or greater than the outlet odor emission standard were businesses associated with surfactant preparation, compounded feed manufacturing, textile dyeing processing, and waste disposal. Due to the separation distance and high exhaust gas flow rate, it was found that odor reduction measures are necessary. In this study, it was possible to present the allowable odor emission concentration at the discharge facilities such as restaurants, livestock houses, and industrial emission facilities by performing the process of verifying the discharge concentration of the actual discharge facility and the result of living odor modeling. It is believed that suitable odor management and prevention facilities can be operated.
Most of the odorous substances generated in public environment facilities are treated using a local exhaust ventilation system. This study assessed the leakage of odorous substances by measuring design criteria, collected air volume, and complex odor in the unit process of sewage treatment facilities. The closer the guideline/design operation airflow ratio of each odor source is to 1.0, the more identical the guideline:design:operation airflow. The average air volume ratio of the facilities under the study was 0.95~0.99 for the MBR process and 0.29~0.68 for the BNR process. As a result of comparing the types of wastewater treatment processes, the leakage of odorous substances was about 9.7 times higher in the BNR process (192,732 m3/min) than in the MBR process (19,838 m3/ min). In this study, it was found that the following two means are important for the proper collection and prevention of odorous substances. The first is the estimation of collection air volume with consideration to the characteristics of the odor source (temperature, odor generation condition, etc.). The second is the design and operation of the local exhaust ventilation system.
This study was performed to evaluate the odor occurrence of offensive leather odor in a district in Gyeonggi-do, where Jeil industrial complex is located, and its residential district, by using olfactory field frequency measurement (Gird Method). In addition, we measured the composite odor. The target points were 9 spots in Jeil industrial complex and 12 spots in the residential district, and we conducted the measurements 13 times each spot. As a result, odor occurrence in descending order was investigated as follows, leather industry > drug industry > food industry. Moreover, odor exposure of the industrial complex exceeded the industrial zone standard of 0.15 (=German odor standard) in all 9 spots (average 0.78). In addition, odor exposure of the residential district exceeded the residential zone standard of 0.10 (=German odor standard) in 12 spots (average 0.78). All the composite odors were below 20 (industrial zone standard). However, as the odor intensity of the sampling site and the lab analysis data showed a large deviation, we found that much supplementation is needed of the odor analysis techniques in the equipment measurement methods.
Recently, public complaints about unpleasant odor are increasing, particularly in urban areas. One of the odor sources is meat grilling restaurants in the vicinity of the residential areas. In this study, we characterized the odorous compounds generated from the stack of grilling restaurants, and evaluated the removal efficiency of the control facilities. As a result of the field investigation, the dilution index of the complex odor exceeded 500 times that of all test restaurants. The main substance was acetaldehyde. In addition, the correlation coefficient (R2) between the total odor and the sum of odor activity values (SOAV) was 0.73, a value high enough to indicate significant responsibility. The performance of the control facility has been shown to be strongly influenced by maintenance activities, such as cleaning and filter replacements.
The stench of various sources has become a complex issue that all governments must face and solve. n-Butanol is often used as an odor intensity reference for daily air quality monitoring and evaluation. However, its odor space, including odor sensation and odor effect, is still not fully understood, especially in wide concentration ranges. This study described n-butanol odor character profiles with objective descriptors. They are mostly presented as “odorless” or “offensive” at low concentrations, and frequently characterized as “chemical” or “medicinal” at high concentrations. The semantic differential shows that n-butanol odor is a negative emotional odor rather than a positive one. The principal component analysis shows that the representative factors of the n-butanol sensibility structure according to the sensibility evaluation are expressed with diverse sensibility vocabulary, and ‘esthetics’ represent its characterless nature. The good linearity between intensity and concentration, the near absence of gender difference, diverse odor types rather than a specific type, and ease with which to make a wide range of concentrations, makes n-butanol a candidate to be considered as a suitable standard odorant.
The odor substances generated in a feed manufactory operating for the commercialization of animal-vegetable materials were analyzed and the odor reduction efficiency by a chemical scrubber was evaluated. The major causative substances in the feed manufactory comprised about 45.4% of ketone compounds and about 13.3% of aldehyde compounds. On the other hand, the removal efficiencies of diacetyl and acetoin as ketone compounds were 77.3% and 78.1%, respectively, by a chemical scrubber. Additionally, the removal efficiencies of acetaldehyde, butyraldehyde, valeraldehyde, 2-furancarboxaldehyde, and nonanal were 86.0%, 78.9%, 67.4%, 52.8%, and 71.9%, respectively. These rates were higher than the odor generation substance contribution rate as a result of treating the exhaust gas generated from the feed manufactory by the chemical scrubber using 5% of C3. It was also found that xylene, methylcyclopentane, benzene, ethylbenzene, 1,3,5-trimethylbenzene, and decane were almost not removed.
The purpose of this study is to produce an adsorbent material with biomass by-product that are readily visible in daily life. The biomass by-product used in the study are coffee grounds, oak leaves and chestnut peels. These biomass by-products were produced with dry, carbonization and activation treatments. The equipment for the evaluation of adsorption capacity was the batch type system to measure the concentration of test gases with the odor sensor device. Biomass by-products have been shown to improve the absorption characteristics of adsorbent through carbonization and activation. The adsorbent made with coffee grounds and chestnut peels had superior adsorption capacity to hydrogen sulfide (H2S) and complex odor (H2S & NH3) in a comparison with regular activated carbon. The odor sensor device could be used to evaluate the device of adsorption capacity of the adsorbent.
The changes in the aroma and spoilage odor emitted from eleven ‘Hongro’ apples during ten weeks’ storage were investigated using six types of metal oxide semiconductor gas sensor arrays. The gas sensors used in the evaluation were sensitive to apple-emitted aroma or spoilage odor, and a high reproducibility of 5% relative standard deviation or less was confirmed. Significantly, the change in apple-emitted aroma or spoilage odor was easily distinguished by the optimal gas sensor and a significant correlation (r=0.992) between decay rate and sensitivity change was observed. The results of a principal component analysis of the signal patterns obtained by data standardization using the optimal gas sensor showed a clear classification between decayed sampler groups and undecayed sampler groups.
In order to reduce odor and methane emission from the landfill, open biocovers and a closed biofilter were applied to the landfill site. Three biocovers and the biofilter are suitable for relatively small-sized landfills with facilities that cannot resource methane into recovery due to small volumes of methane emission. Biocover-1 consists only of the soil of the landfill site while biocover-2 is mixed with the earthworm casts and artificial soil (perlite). The biofilter formed a bio-layer by adding mixed food waste compost as packing material of biocover-2. The removal efficiency decreased over time on biocover-1. However, biocover-2 and the biofilter showed stable odor removal efficiency. The rates of methane removal efficiency were in order of biofilter (94.9%)>, biocover-1(42.3%)>, and biocover-2 (37.0%). The methane removal efficiency over time in biocover-1 was gradually decreased. However, drastic efficiency decline was observed in biocover-2 due to the hardening process. As a result of overturning the surface soil where the hardening process was observed, methane removal efficiency increased again. The biofilter showed stable methane removal efficiency without degradation. The estimate methane oxidation rate in biocover- 1 was an average of 10.4%. Biocover-2 showed an efficiency of 46.3% after 25 days of forming biocover. However, due to hardening process efficiency dropped to 4.6%. After overturn of the surface soil, the rate subsequently increased to 17.9%, with an evaluated average of 12.5%.
In this study, a correlation analysis of odor was performed in order to assess the reliability and the field applicability of the Odorous gas sensor for continuous real-time monitoring. Hydrogen sulfide was found to have a correlation of 41.5~65.8%, and Ammonia is was found to have very low correlation in less than 200 ppb concentration. Reactivity evaluation result, hydrogen sulfide is the reactivity was higher than the low concentration condition of 100 ppb or less indicated by 31.3~36.4% in the 100 ppb or more high density condition based on the reference density value. For ammonia was very low reactivity in the low-concentration conditions below 200 ppb. TVOC and composite odor assessment did not occur Reactivity no reference concentration value, the specific comparison between both sensors showed a similar trend. In the same Odorous gas sensor accuracy between the result, 40.3~130.6% hydrogen sulfide, ammonia, 69.1~104.9%, TVOCs is 24.7~98.6%, exhibited human odor intensity from 5.5~33.2%.
The object of this study is to investigate the relationship between the air dilution sensory test and the threshold odor number (TON) method for evaluating the odor of domestic wastewater, plating plant wastewater, food plant wastewater and lake water. The dilution factor of raw wastewater evaluated by the air dilution sensory test was in the order of food plant > plating plant > domestic > lake, and that evaluated by the threshold odor number method was in the order of food plant > domestic > plating plant > lake. The same results were obtained when the raw wastewater and lake water were diluted 2 and 5 times with pure water. The relative geometric standard deviation determined from the threshold values of each panel on the air dilution sensory test was much larger than that calculated from results derived from the threshold odor number method. The relative geometric standard deviation obtained from samples with a low dilution factor was greater. There was a very good linear correlation (correlation coefficient = 0.968~1.000) between the air dilution sensory test and the threshold odor number method. But, the reduction in odor intensity (the slopes of regression curves) by dilution was dependent on the types of the odor-emission sources.
향-냄새에 대한 감수성은 종족, 성에 따라 상이하며 냄새에 대한 인지력과 식별력은 가령화에 따라 쇠퇴한다고 한다. 가령화에 따른 향의 평가에 관한 선행보고들은 그 대상이 유아에서 노인에 이르기까지 다양함에도 불구하고 제시 향에 단순 알코올이나 단순 초산염이 주로 사용되었으며, 냄새 인지력이나 식별력 둥 지성적인 측면에서의 평가가 대부분이었다. 본 연구에서는 후각기능이 정상인 19~68세 50명을 대상으로 6종의 천연향에 대해 안정/폐안 상태에서 ECG, 피부저항, 그리고 주관평가를 실시하여 서로 다른 연령층에 따른 변화를 살펴보고자 하였다. 그 결과, 20대, 40대의 청\ulcorner중년층은 lemon을, 60대는 Lavender를 긍정적으로 반응\ulcorner평가하였다. 특히 40대 그룹은 평균 RR 간격, 심박수, 피부저항, 주관평가의 결과에서 가장 높은 상관성을 보여 후각기능이 가장 성숙한 연령대임이 확인되었다. 제시 향에 대해 연령별로 상이하게 반응/평가한 본 연구결과는 연령별로 차별화된 향장품 개발뿐만 아니라 인공냄새 그리고 맛의 개발에도 응용이 가능할 것으로 여겨진다.