This ammonia prediction study was performed using the time-series artificial neural network model, Long-short term memory (LSTM), after long-term monitoring of ammonia and environmental factors (ventilation rate (V), temperature (T), humidity (RH)) from a slurry finishing pig farm on mechanical ventilation system. The difference with the actual ammonia concentration was compared through prediction of the last three days of the entire breeding period. As a result of the analysis, the model which had a low correlation (ammonia concentration and humidity) was confirmed to have less error values than the models that did not. In addition, the combination of two or more input values [V, RH] and [T, V, RH] showed the lowest error value. In this study, the sustainability period of the model trained by multivariate input values was analyzed for about two days. In addition, [T, V, RH] showed the highest predictive performance with regard to the actual time of the occurrence of peak concentration compared to other models . These results can be useful in providing highly reliable information to livestock farmers regarding the management of concentrations through artificial neural network-based prediction models.

This study aimed to investigate the characteristics of odor-causing substances in Yeosu national industrial complex, which is designated as an “Odor management Area,” in 2019 and the surrounding area. The sampling sites were divided into three areas: five sites within the industrial complex (Management area), one site within the borders of the complex (Boundary area), and two sites within residential areas (Affected area) affected by odors. The odor compounds were collected from March to September at dawn, daytime, and night. The analytical items were meteorological data, complex odor, legally-designated 22 odor compounds and other VOCs. Complex odor was exceeded on the limit three occasions at two sites in the management area. Ammonia, two types of sulfides, three types of aldehydes, and five VOCs were detected to be within the emission standards. Ammonia was the most frequently detected compounds. Aldehydes and sulfur compounds made a relatively high contribution to the level of odors. Therefore, aldehydes and sulfur compounds should be reduced first in order to prevent odors from occurring.

This study was conducted to find an efficient and economical mixing ratio of deodorant and a isolated microorganism to reduce ammonia in livestock manure compost. In this study, a simple experimental device that can compare the degree of odor reduction by connecting the vial containing the odor generating source and the gas detection tube and leaving it to stand was used. This test method cannot accurately measure ammonia concentration according to the characteristics of the detector tube, but it is an easy method to compare various experimental conditions. The microorganism isolated from pig manure, “Enterococcus casseliflavus” was found to have an effect on ammonia reduction. Surfactant (sodium dodecyl sulfate), mineral A, mineral B, sulfur, persimmon leaves, and glycerin used as a deodorant were mixed with E. casseliflavus NO-2-L to find the optimum mixing ratio. When 20% of deodorants and E. casseliflavus NO-2-L were added to the source of odor alone, the ammonia reduction efficiency of NO-2-L was the highest (66.7%) compared with other deodorants. When a mixture of microorganisms and deodorants were used, the ammonia reduction efficiency was the best when the mixing ratio of the deodorant was 20%. When mineral B and sulfur were added, the ammonia concentration reduction efficiency was the highest at 83.3%.

The emission of particulate matter and volatile organic compounds (VOCs) from a motor vehicle painting booth was quantitatively evaluated. Most particulate matter was emitted during the spraying process, in which the PM10 concentration was 16.5 times higher than that of the drying process. When the paint was being sprayed, the particles with a diameter of 1.0~2.5 μm accounted for 39.4% and particles greater than 2.5 μm in diameter accounted for 30.6% of total particles. On the other hand, small particles less than 0.5 μm in diameter accounted for 52.4% of total particles during the drying process. In contrast to the particulate matter, high concentrations of VOCs were emitted during both spraying and drying processes. Butyl acetate, xylene, toluene, and m-ethyltoluene were the most abundant VOCs emitted from the motor vehicle painting booth. Additionally, xylene, butyl acetate, toluene, and 1,2,3-trimethylbenzene were the dominant ozone precursors. Especially, xylene exhibited the highest ozone production contribution (32.5~44.4%) among 34 species of the ozone precursors. The information obtained in this study can be used to establish a suitable management strategy for air pollutants from motor vehicle painting booths.

The objective of this study is to identify the emission characteristics of VOCs from small-scale painting facilities, such emissions being pollutants that impact nearby living areas and to devise improvement measures to enhance management plans regarding pollutant emissions from painting facilities. VOCs emissions from painting facilities were estimated according to Clean Air Policy Support System (CAPSS) data based on the National Institute of Environmental Research (NIER)'s emission list in 2017. Three automotive painting facilities in Seoul were chosen for evaluation of the adsorption system. We analyzed the characteristics of VOCs generated by type of different operation and measured the removal efficiency of the adsorption system. Therefore, we analyzed current emissions of VOCs from automotive painting facilities based on field measurements. According to such detailed analysis, a systematic management plan was proposed.

This study was carried out in order to help establish a continuous efficiency test method to evaluate the performance of chemical odorants. We designed a continuous efficiency test device, and conducted several experiments during 240 mins with D.W. and two chemical deodorants for several specified substances, and a complex odor compound. Based on the results, it was confirmed that the deocorant test only for ammonia and amine could yield no useful outcome because the solubility of the two compounds was very high. Henceforth, simultaneous tests for sulfides, mercaptans, aldehydes, and so on, shoud be conducted in order to ascertain the accurate deodorant performance results. It is also clear that the concentration of target compounds and reaction time are very important for the purposes of accurate deodorant tests. In addition, information about the absorption efficiency with regard to complex odor compound such as DMS+DMDS may be important and the results based on air dilution olfactory method should be provided. It is believed that this study can make a contribution to formulating the correct standards regarding the testing of deodorants and the application of such tests.

Environmental fundamental facilities have different odor emission characteristics depending on the type of treatment facilities. To overcome the limitations of the olfactometry method, research needs to be conducted on how to calculate the dilution factor from the individual odor concentrations. The aim of this study was to determine the air dilution factor estimated from manually measured concentration data of individual odor substances (22 specified odor species) in three environmental treatment facilities. In order to calculate the optimum algorism for each environmental fundamental facility, three types of facilities were selected, the concentration of odor substances in the exhaust gas was measured, and the contribution of the overall dilution factor was evaluated. To estimate the dilution factor, four to six algorism were induced and evaluated by correlation analysis between substance concentration and complex odor data. Dilution factors from O municipal water treatment (MWT) and Y livestock wastewater treatment (LWT) facilities showed high level of dilution factors, because concentration levels of hydrogen sulfide and methylmercaptan, which had low odor threshold concentrations, were high. In S food waste treatment (FWT) facility, the aldehyde group strongly influenced dilution the factor (dominant substance: acetaldehyde, i-valeraldhyde and methylmercaptan). In the evaluation of four to six algorism to estimate the dilution factor, the vector algorism (described in the text) was optimum for O MWT and Y LWT, while the algorism using the sum of the top-three dominant substances showed the best outcome for S FWT. In further studies, estimation of the dilution factor from simultaneously monitored data by odor sensors will be developed and integrated with the results in this study.

In this study, a manganese catalyst on the surface of a ceramic support was developed for the removal of odor emitted from barbecuing restaurants. Its ozone oxidation at room temperature was tested using acetaldehyde (CH3CHO), the most dominant compound in the barbecuing odor, and the ozonation efficiency under wet conditions was also studied. The manganese catalyst was made with the honeycomb-type ceramic support, and an acid pretreatment was applied to increase its specific surface area, resulting in an increase of the degree of dispersion of manganese oxide. The acetaldehyde removal efficiency using the manganese catalyst on the acidpretreated support (Mn/APS) increased by 49%, and the ozone decomposition rate and the CO2 conversion rate also increased by 41% and 27%, respectively. The catalyst without surface pretreatment (Mn/S) showed a low efficiency for the acetaldehyde ozonation, and other organic compounds such as acetic acid (CH3COOH) and nonanal (CH3(CH3)7CHO) were found as oxidation by-products. In comparison, CO2 was the most dominant product by the ozonation of acetaldehyde using the Mn/APS. When the relative humidity was increased to 50% in the influent gas stream, the acetaldehyde removal efficiency using the Mn/APS decreased, but only the production rates of CO2 and acetic acid were changed. As a result, the manganese oxide catalyst on the surface of the acid-pretreated honeycomb support manifested high acetaldehyde ozonation even at humid and room temperature conditions.

To obtain information on the indoor air quality of un-disinfected libraries used for paper records preservation, temperature, humidity, and bacterial concentration and species were investigated at five un-disinfected libraries from May to September in 2019 in the National Archives, Seoul (Nara Repository), Korea. Temperature and humidity of all the five un-disinfected libraries were well maintained at 18-22oC and 40-55% in compliance with the National Archives Paper Records Preservation Environment Standard. Bacterial concentration ranged from 2 CFU/m3 up to 280 CFU/m3 which were lower than the Korean indoor air quality standard value. A total of 68 bacterial species belonging to 33 genera were identified from indoor air of the five un-disinfected libraries. Among the 33 genera, Bacillus, Micrococcus, and Staphylococcus were the major genera. Only Micrococcus yunnanensis, Roseomonas mucosa, and Moraxella osloensis were commonly found among the five un-disinfected libraries. Bacterial species producing colonies with color on TSA media were present. Among the 68 species, Bacillus circulans and B. megaterium known to produce cellulases were found. There were also 17 species which have harmful effect on human health. The results of this study indicate that continuous monitoring of air borne bacteria is necessary in the un-disinfected libraries used for paper records preservation.

This study obtained the following conclusions using the measurement results of indoor and outdoor PM10 with regard to cardiovascular disease patients in Cheongju-area in November 2020. Most of the PM10 has an I/O ratio of less than 1, which is an outdoor source. Since we measured once and twice time, Without the air purifier device’s working status, there were no concentration changes of PM10 in the first and second indoor areas. As for the concentration of PM10 according to the living environment, the distribution of PM10 is higher indoors than outdoors when the residential area is 30 m2 or more, and the outdoor PM10 concentration tends to be high when the distance to the road is within 50 m. The more time spent indoors, the higher the indoor PM10 concentration. The smaller the ventilation time and frequency, the longer the cooking time was, and the higher the number of cooking times, the higher the concentration of PM10 could be. The indoor PM10 contribution ratio through multiple regression analysis showed the possibility of increasing indoor PM10 as β = 28.590 when the time spent indoors was longer than 16 hours (p<0.05). The result regarding PM10 exposure reveals that PM10 can be inhaled not only indoors but also outdoors, and the subjects of this study appear to have lived indoors for about 16 hours or longer on a daily basis, which may affect their health regardless of gender.