The research aimed to develop a high-efficiency plate-type heat exchanger for exhaust gas using computational fluid dynamics (CFD) thermal analysis based on the plate shape, and to identify the optimal shape. Following this, a water/air plate heat exchanger was manufactured, and its characteristics were studied experimentally. As the Re number increases on the gas (or air) side, the heat transfer rate increases significantly, whereas an increase in the Re number on the water side leads to a smaller increase in heat transfer. This is attributed to the larger convective heat resistance on the gas side, causing a substantial reduction in gas-side heat resistance as gas velocity increases, resulting in a considerable overall reduction in heat resistance. The fluid flow pressure drop showed similar results between the CFD calculations and experimental outcomes.

Since the implementation of the Odor Prevention Act in 2005, the number of odor complaints has continuously increased due to the increased interest in the living environment. The current odor control means is a concentrationbased method for the source of odor. That is why there is a difference between the odor sensitivity and the result of the odor measurement in the odor damage area. The government is considering the introduction of the grid method, which is the odor management method of Germany, as the method of odor investigation in the odor damage area in the second comprehensive Odor Prevention Policy (2019-2028). The grid method is receptor-based odor measurement method that investigators use to judge odors in the field, task that expensive and requires substantial manpower and time. To study an odor measurement method that is suitable for domestic conditions, this study compared the correlation between results based on the odor frequency concept grid method around the livestock facilities and the result of ammonia concentration measured by passive air sampler. The correlation coefficient (R) that is between the frequency of odor per spot for the entire odor and the ammonia concentration that was measured by passive air sampler was 0.65 which is relatively good. Among the entire odor detected by the grid method, the correlation coefficient (R) between the odor frequency selected only for livestock odor and the ammonia concentration was significantly increased to 0.80. In addition, the correlation between odor exposure (ECPexist) and the ammonia concentration for the overall odor was 0.81 (linear) and 0.86 (index). If only the livestock odors were selected, the correlation between odor exposure and the ammonia concentration was very high at 0.96 (linear) and 0.95 (index).

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.

This study was designed to assess the odor characteristics of paprika with metal oxide gas sensors. Non-decayed paprika and decayed paprika were assessed by sensor array system comprising 10 kinds of sensors. Three representative sensors were selected from among the 10. Selection was based on a correlation analysis between sensors from the results of the sensor array assessment on non-decayed paprika. It was found that the odor variation characteristics of paprika can be assessed by metal oxide gas sensors and that the odor variation characteristics of paprika are different depending on the type of gas sensors. The odor characteristics of paprika were different according to the color, the presence or absence of decay, the location of decay, the type of sensor, and the passage of time. Regardless of decay, the sensor response value of orange paprika was the highest, with the 2611 sensor yielding the highest response value. The SB-AQ1 sensor could not identify the difference in odor characteristics depending on the location of decay, while detection was possible by both SB-41 and 2611 sensors.

The purpose of this study is to evaluate the performance of a tube and badge type NO2 passive air sampler. The principle of the method is a colorimetric reaction of NO2 with N-1-naphthylethylendiamine under acidic conditions. The sampling rates for the tube and badge type passive air samplers was determined 12.3 ± 4.4 mL/min and 27.3 ± 4.9 mL/min, respectively, as obtained from the slope of the linear correlation between the NO2 mass collected by the passive air sampler and the NO2 concentration with the NO2 analyzer. The tube and badge type passive air sampler were moderately correlated with a correlation coefficient of 0.9112. The measurement for the precision and accuracy of the passive air sampling was carried out with duplicate measurement of passive air samplers. The passive air sampler had good precision and accuracy for measuring NO2 in atmosphere. A good correlation was observed between the passive air sampler and the NO2 analyzer with a coefficient of determination of 0.9153 (tube type) and 0.9514 (badge type). This passive air sampler would be suitable for the NO2 concentration monitoring in atmosphere.

The emission characteristics of VOCs (Volatile Organic Compounds) from assembly metal product manufacturing industry (Korean standard industry classification code: 28) were studied. The sampling was carried out at 54 sites in Shiwha-Banwol industrial area with 3 M OVM (Organic Vapor Monitor) #3500 from August to October in 2008. The EPA 8020/8040 (10 chemicals) was used as a standard solution for the quantitative analysis with GC/FID. As the results, the VOCs concentration appeared to range from 0.9 ppb to 22,721.1 ppb, and the average concentration ratio of benzene : toluene : ethylbenzene : m,p-xylene : o-xylene : styrene appeared to be 0.005 : 1.000 : 0.198 : 0.096 : 0.057 : 0.110. Total VOC concentration of the "Manufacture of Structural Metal Products, Tanks, Reservoirs and Steam Generators" (KSIC code: 281) appeared to be seven times higher than that of "Manufacture of other fabricated metal products; metal working service activities" (KSIC code: 289).

The application of gas sensors for the measurement of environmental odor was investigated. The test chamber systems were consist of three parts, as it were, sample injection, odor sensing and data process parts. Four type of sensors were tested with regard to sensor performance like baseline stability, sensitivity and reproducibility to H₂S, CH₃SH, NH₃, and (CH₃)₃N gases. As the results, two kinds of sensors were content with the circuit conditions used in this study. In addition, the influence of relative humidity to the selected two types sensors was tested. The [mal sensor, which was appeared to be the most stable sensor against relative humidity, was selected, and applied practically to measure the real odor from the manure odor source.