• 한국축산시설환경학회지
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• 제5권2호
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• pp.123-132
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• 1999

This study was carried out to find deodorization management method of the efflux from swine slurry treated by thermophilic aerobic oxidation reactor. Three kinds of deodorization methods in Lab-scale reactors, were used in this experiment; No treatment, air injection treatment(50$m\ell$ air/min. $\ell$) and inoculumn of photrophic bacteria treatement(108 cell(Most probable number, MPN)/$m\ell$). The concentration of volatile fatty acids(VFAs), hydrogen sulfide(H2S), and ammonia(NH3) were analyzed during the treatment period(50 days). The major results obtained as follows. 1. Air injection method to efflux showed very high removal effect on malodorants such as VFAs, hydrogen sulfide(H2B). But ammonia(NH3) was emitted to much. 2. PTB inoculum method was also effective in removal of malodorants, VFAs, Hydrogen sulfide(H2S), when it was applied to the efflux. 3. We found that the concentrations of malodorants, VFAs, H2S, NH3 had some relatinships with the pH, ORP, BOD in the efflux.

• 생태와환경
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• 제38권4호통권114호
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• pp.435-438
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• 2005

We observed the physical, chemical, and biological characteristics of an acidic lake, Lake Katanuma, from 1998 to 2002 at weekly or biweekly intervals, except during the winter. This volcanic lake has a dimictic thermal pattern. In summer, the volcanic heat supply at the lake bottom results in weak thermal stratification. In 1998, 1999, and 2002, short-term holomixis was observed during the stratification period, when the anoxic, hydrogen sulfide-rich water from the hypolimnion spread across the entire lake. In contrast, distinct short-term holomixis did not occur during the stratificatlon period in 2000 and 2001. However, the early onset of the autumn turnover in August 2000 and 2001 caused anoxic conditions to persist throughout the entire water column for more than 2 weeks. The anoxic and hydrogen sulfide-rich conditions affected population densities of chironomid larvae (Chironomus acerbiphilus) and planktonic algae (Chlamydomonas acidophila), both dominant species in Lake Katanuma. Thus, the interannual variations of limnological characteristics influenced the seasonal population changes of these species.

• Asian-Australasian Journal of Animal Sciences
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• 제18권4호
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• pp.574-579
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• 2005

Optimal management of indoor air quality in a confined pig house, especially in winter, is indispensable for preventing infectious respiratory disease to workers and animals. This study was performed to elucidate the correlation of aerial contaminants and climate factors in a confinement. It was observed that indoor air contaminants ion in the confinement was the highest at 2:00-5:00 pm in a day, followed by 8:00-11:00 pm and 8:00-11:00 am. This was attributed to the increase of pig activities in the afternoon. The concentration of total dust and total airborne bacteria was found to have a significant correlation with temperature and relative humidity (p<0.05). Correlation of total dust and total airborne bacteria, total dust and ammonia, and total dust and odor were shown statistically significant at 95% confidence level. In conclusion, temperature and total dust concentration correlated significantly with all the parameters except for hydrogen sulfide ($H_2S$). This could be explained by the fact the dryness of pig feces by increase of interior temperature and resuspension of feed deposited on the floor by the pig activity, resulted in high generation of dust which adsorbed and carried the airborne bacteria and odor compounds in a confined pig house. It was proved that the adsorptive capacity of dust with ammonia ($NH_3$) was higher than that with hydrogen sulfide ($H_2S$).

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.450-450
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• 2011

This study reports the hydrogen sulfide gas sensing properties of ZnO nanorods bundle and the investigation of gas sensing mechanism. Also the improvement of sensing properties was also studied through the application of ZnO heterstructured nanorods. The 1-Dimensional ZnO nano-structure was synthesized by hydrothermal method and ZnO nano-heterostructures were prepared by sonochemical reaction. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectra confirmed a well-crystalline ZnO of hexagonal structure. The gas response of ZnO nanorods bundle sensor increased with increasing temperature, which is thought to be due to chemical reaction of nanorods with gas molecules. Through analysis of X-ray photoelectron spectroscopy (XPS), the sensing mechanism of ZnO nanorods bundle sensor was explained by well-known surface reaction between ZnO surface atoms and hydrogen sulfide. However at high sensing temperature, chemical conversion of ZnO nanorods becomes a dominant sensing mechanism in current system. In order to improve the gas sensing properties, simple type of gas sensor was fabricated with ZnO nano-heterostructures, which were prepared by deposition of CuO, Au on the ZnO nanorods bundle. These heteronanostructures show higher gas response and higher current level than ZnO nanorods bundle. The gas sensing mechanism of the heteronanostructure can be explained by the chemical conversion of sensing material through the reaction with target gas.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권2호
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• pp.914-922
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• 2019

Gas composition has a significant impact on the dispersion behavior and accumulation characteristics of blowout gas. However, few public studies has investigated the corresponding effect of gas composition. Therefore, this study firstly builds the FLACS-based numerical model about an offshore drilling platform. Then several scenarios by varying the composition of blowout gas are simulated while the scenario with the composition of "Deepwater Horizon" accident is regarded as the benchmark. Furthermore, the effects of the gas composition on the flammable cloud volume, the influenced area of flammable cloud, the influenced area of hydrogen sulfide and the critical time of the hydrogen sulfide spreading to the living area are analyzed. The results demonstrate that gas composition is a driving factor for dispersion characteristics of blowout gas. All the results can give support to reduce the risk of the similar accidents incurred by real blowouts.

• Environmental Engineering Research
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• 제24권4호
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• pp.572-581
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• 2019

The emission of hydrogen sulfide (H₂S) from the Kahrizak landfill was studied. Firstly, the field measurements were conducted in the summer and winter seasons; and the samples were analyzed using Jacob method. We predicted the H₂S concentrations in the downwind using AERMOD and ISCST3. According to the AERMOD, the maximum concentration of H₂S in the summer and winter were 117 ㎍/㎥ and 205 ㎍/㎥ respectively. The downwind concentrations reached zero at the distance of 35 km from the leachate treatment plant. The Geometric mean bias, Geometric variance, Fractional bias, Fraction of predictions within a factor of two of the observations and Normalized mean square error for the AERMOD were 0.58, 1.35, -0.12, 1.91 and 0.042, respectively in the summer and 1.39, 1.35, -0.05, 1.46 and 0.027 in the winter; and for the ISCST3, were 0.85, 1.03, 0.02, 1.45 and 0.04 in the summer and 1.18, 1.03, 0.15, 1.16 and 0.04 in the winter. The results of the AERMOD were compared with the ISCST3 and indicated that the AERMOD performance was more suitable than the ISCST3.

• Korean Chemical Engineering Research
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• 제45권4호
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• pp.372-377
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• 2007

본 연구에서는 생물학적 공정을 사용하여 황화수소를 제거하는데 있어 망상구조의 폴리우레탄 담체의 바이오필터 충진물로서의 특성을 유입가스농도와 유입가스량의 두 변수를 대상으로 조사하였다. 실험결과 망상구조의 폴리우레탄 담체를 적용한 바이오필터의 황화수소 최대제거용량은 $488.3g-H_2S/m^3{\cdot}h$이었으며, 추정된 임계부하속도는 $330.1g-H_2S/m^3{\cdot}h$이었다. 본 연구의 결과 망상구조의 폴리우레탄 담체를 황화수소의 생물학적 처리를 위한 바이오필터의 담체로서 적용가능성을 확인하였다.

• 한국지반환경공학회 논문집
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• 제8권4호
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• pp.41-45
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• 2007

바이오필터의 운전에 있어 큰 표면적, 높은 한계 역압력을 가지고 있는 충진 담체의 선택은 매우 중요하다. 본 연구의 목적은 황산화 세균을 분리하고 분리된 황산화 세균과 바이오필터를 이용해 담체 종류에 따른 황화수소의 제거특성을 조사하는 것이며 연구결과는 다음과 같다. 1) 전남 화순의 폐탄광 폐수에서 Thiobacillus sp. IW.를 분리하였다. 2) 다양한 담체를 이용해 유입농도, 공간속도에 따른 바이오필터의 황화수소 제거특성 및 압력손실 변화 살펴본 결과 무기성 담체가 유기성 담체에 비해 우수한 성능을 나타내었다. 3) 무기성 담체 중에서는 섬유상, PU 담체가 다른 담체에 비해 우수한 성능을 나타내었다.

• 한국대기환경학회지
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• 제27권4호
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• pp.379-386
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• 2011

Catalyst-assisted plasma system with a DBD (Dielectric Barrier Discharge) reactor was used to remove hydrogen sulfide, which is one of the odorous species in this study. The ${\gamma}-Al_2O_3$ and ${\beta}$-Zeolite catalysts impregnated by Ag, Cu and Mn species were employed as catalysts and their $H_2S$ removal characteristics under plasma irradiation were investigated. From the experimental study, we found that the $H_2S$ removal efficiency increases with decreasing space velocity in the system and increasing specific input energy. Furthermore, ${\beta}$-Zeolite catalysts are efficient to remove $H_2S$ than ${\gamma}-Al_2O_3$ catalysts. Especially, the catalysts impregnated by Ag have higher removal efficiency than other catalysts (Cu, Mn).

• 산업기술연구
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• 제39권1호
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• pp.41-45
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• 2019

Hydrogen sulfide ($H_2S$) is mainly produced along with methane and hydrocarbons in many gas fields as well as hydrodesulfurization processes of crude oils containing sulfur compounds and the emission of $H_2S$ has a considerable effect on both environmental problem and human health aspects due to formation of, e.g. acid rain and smog. In recent years, ionic liquids (ILs) have been proposed as the most promising solvents for $CO_2$ and hazardous pollutants capture, such as $H_2S$ and sulfur dioxide ($SO_2$). In this work, we demonstrate the use of the predictive COSMO-SAC model for the prediction of Henry's law constant of $H_2S$ in ILs. Furthermore, the method is used to screen for potential IL candidates for $H_2S$ capture from a set of 2,624 ILs formed from 82 cations and 32 anions. The effects of cation on the Henry's law constant of $H_2S$ such as (i) the variation of the alkyl chain length on cation, (ii) the substituent of methyl group ($-CH_3$) for H in C(2) position and (iii) the change of ring structure for cation family are clearly predicted by COSMO-SAC model.