• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2013년 춘계학술대회
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• pp.655-668
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• 2013

In this study, a combination of the plasma discharge in the reactor by the reaction surface discharge reactor complex catalytic reactor and air pollutants, hazardous gas SOx, change in frequency, residence time, and the thickness of the electrode, the addition of simulated composite catalyst composed of a variety of gases, including decomposition experiments were performed by varying the process parameters. 20W power consumption 10kHz frequency decomposition removal rate of 99% in the decomposition of sulfur oxides removal experiment that is attached to the titanium dioxide catalyst reactor experimental results than if you had more than 5% increase. If added to methane gas was added, the removal efficiency increased decomposition, the oxygen concentration increased with increasing degradation rate in the case of adding carbon dioxide decreased.

• 한국대기환경학회지
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• 제20권1호
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• pp.77-85
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• 2004

In this study, the concentrations of reduced S compounds (including hydrogen sulfide (H$_2$S); methyl mercaptan ($CH_3$SH); dimethyl sulfide (($CH_3$)$_2$S); carbon disulfide (CS$_2$); and dimethyl disulfide (($CH_3$)$_2$S$_2$) were determined from landfill gas (LFG) in three municipal landfill sites in the two cities of Gwang Ju (GJ) and Jeju (JJ), Korea. The S gas concentrations measured in these landfill sites were found to be dominated by H$_2$S with its mean concentration of 850 ppm from 10 LFG samples. Both absolute and relative dominance of H$_2$S was seen to be significant in most LFG samples, except those collected from very old and inactive landfills. Unlike the pattern of H$_2$S, other S gases were typically observed at much reduced concentration levels (a few ppm or less) as follows: DMS (3.5); $CH_3$SH (1.3); CS$_2$(1.2); and DMDS (0.02 ppm). If compared equally in mass concentration unit (mg m$^{-3}$ ), H$_2$S generally explained far above 90% of all S gas masses determined concurrently. Moreover, as its mass concentration commonly exceeds those of the major aromatic VOC components in LFG (like benzene and toluene), it appeared to be one of the most dominant gaseous components emitted as LFG in a quantitative sense.

• Tribology and Lubricants
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• 제13권4호
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• pp.60-65
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• 1997

The tungsten disulfide $(WS_2)$ solid lubricant was synthesized by two different reaction processes, i.e., the reaction between $CS_2$ gas phase and solid $WO_3$powder, and the vapour phase transport method of tungsten and sulfur in a high vacuum. The chemical and physical characteristics of synthesized $WS_2$powder were analyzed in terms of the average particle size, morphology, crystalline phase etc. in comparison with those of commercial $WS_2$powder. The solid $WO_3$ powder with the average size of 0.2 ${\mu}{\textrm}{m}$ was reacted with $CS_2$gas flowed with$N_2$or 96%$N_2{\times}4%H_2$forming gas for 36 h and 24 h at 90$0^{\circ}C$ respectively. $WS_2$ crystalline phase was then formed through the intermediate phase of .$W_{20}O_{58}$ In the case of vapour phase transport method, the 3.5 wt% iodine was added as a vapour transport reagent into the composition of tungsten and sulfur powders maintaining a constant molar ratio of W:S=1:2.2. The mixture was then heat treated at 85$0^{\circ}C$ for 2 weeks in vacuum. The reaction product obtained showed the average size of 12 ${\mu}{\textrm}{m}$ and the hexagonal plate shape of typical solid lubricant with 2H-$WS_2$crystalline phase.

• 플랜트 저널
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• 제4권4호
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• pp.71-77
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• 2008

The sulfur oxides is one of important materials to come about air pollution at thermal plant consuming fossil fuel. The several flue gas desulfurization equipments are installed and operated to decrease sulfur oxides. The flue gas desulfurization of our thermal plant is designed for optimizing flue gas desulfurization technical development and research by Korea Electric Power Research Institute. We operate this desulfurization equipment. Now, our country imports nearly 97 percentage of the energy source and competes with the world for the energy because of the sudden rise of raw materials cost. The fuel cost decrease of power plants is the most important factor of the operation. The fuel used in the experiment is the domestic anthracite from Kangwon Taeback and the bituminous coal from Taldinsky Mine in Russia. This Study is experimental investigations of desulfurization characteristics for domestic anthracite power plant by increasing bituminous coal. We surveyed possible parameters and conducted the performance about desulfurization equipment in Yong Dong thermal power plant.

• 한국표면공학회지
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• 제54권2호
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• pp.43-52
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• 2021

The Ni-based superalloy, Inconel 740, was corroded between 800 and 1100℃ for up to 100 hr in air and Ar-0.2%SO₂ gas in order to study its corrosion behavior in air and sulfur/oxygen environment. It displayed relatively good corrosion resistance in both environment, because its corrosion was primarily dominated by not sulfidation but oxidation especially in Ar-0.2%SO₂ gas. Such was attributed to the thermodynamic stability of oxides of alloying elements when compared to corresponding sulfides. The scales consisted primarily of Cr₂O₃, together with some NiAl₂O₄, MnCr₂O₄, NiCrMnO₄, and rutile-TiO₂. Sulfur from SO₂ gas made scales prone to spallation, and thicker. It also widened the internal corrosion zone when compared to air. The corrosion resistance of IN740 was mainly indebted to the formation of protective Cr₂O₃-rich oxides, and suppression of the sulfide formation.

• 한국토양비료학회지
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• 제11권2호
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• pp.105-112
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• 1979

대기오염물질의 하나인 아황산가스를 $0.2mg/{\ell}$ 및 $0.5mg/{\ell}$의 농도(濃度)로 대두(大豆)에 접촉(接觸)시켜 접촉시간(接觸時間) 및 시각(時刻)에 따른 피해증상(被害症狀), 피해엽률(被害葉率), 수량(收量), 체내유황함량, 엽록소함량 등(等)을 조사(調査)한 결과(結果)를 보면 다음과 같다. 가, $0.5mg/{\ell}$ 아황산가스를 시간별(時間別)로 접촉(接觸), ${\bullet}$ 5분간(分間)의 단시간접촉(短時間接觸)에서 52%의 감수(減收)를 가져왔고 60분접촉(分接觸)에서 76.4%로 감수(減收)하였다. ${\bullet}$ 가스접촉시간(接觸時間) 및 감수률(減收率)과 체내유황함량은 정(正)의 상관(相關)이 있었고 수용성(水溶性) 유황(硫黃)이 전유황(全硫黃)보다 유의도(有意度)가 높았다. 나, $0.2mg/{\ell}$의 아황산가스를 시각별(時刻別)로 접촉(接觸), ${\bullet}$ 엽피해(葉被害)는 10-11시(時)에 가장 심(甚)하였으며 22-23시(時)에는 육안적(肉眼的) 피해(被害)가 없었다. ${\bullet}$ 엽(葉) 경내 유황함량(硫黃含量)은 10-11시(時)에 가장 많았고 18-19시(時)에 가장 적었으며 엽록소함량은 10-11시(時)에 가장적고 22-23시(時)에 가장 많았다. ${\bullet}$ 엽내유황함량(葉內硫黃含量)과 피해엽률(被害葉率)은 정(正)의 상관이 있었으며 엽록소함량과 피해엽률(被害葉率)과는 부(否)의 상관이 있었다. ${\bullet}$ 엽록체의 흡광도(吸光度)는 10-11시(時)에 가장 감소(減少)가 컸고 22-23시(時)에 가장 감소(減少)가 적었으며 $456m{\mu}$ 및 $663m{\mu}$에서 흡광도(吸光度)의 감소(減少)가 컸다.

• 한국작물학회지
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• 제38권3호
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• pp.283-289
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• 1993

콩의 생육 및 수량에 미치는 대기 중 아황산가스의 영향을 평가하고자 공업단지 주변에서 아황산가스의 농도 측정, 밭토양의 특성조사 및 콩의 생육 및 수량을 조사한 결과를 이용하여 콩의 생육기간중의 아황산가스의 등 농도곡선을 작성하고 이를 이용한 콩의 생육과 수량에 미치는 아황산가스의 영향과 토양 pH의 영향을 검토한 결과는 다음과 같다. 1. 조사지역의 콩의 주요 생육기간인 7월중순부터 9월중순까지의 아황산가스의 평균농도는 77mg /100$cm^2$ PbO$_2$/day였다. 2. 콩의 수량감소율은 5～30% 정도였으며, 7월중순부터 9월 중순까지의 아황산가스농도와 수량과는 유의 한 부의 상관관계 (r=-0.846＊＊)를 보였다. 7월 16일부터 8월 9일까지의 아황산가스의 농도와 주당 협수 및 100립 중, 8월 9일부터 9월 17일까지의 아황산가스의 농도와 100립중과는 유의한 상관관계를 보이지 않았다. 3. 조사지역의 토양 pH는 4.2～6.5였으며, 토양의 pH와 수량과는 正의 상관관계(r=0.813＊＊)를 보였으며, 석회시용으로 토양 pH가 교정된 곳에서는 아황산가스에 의한 수량감소가 적었다. 4. 콩의 수량 형성에 미치는$SO_2$의 영향은 만성적, 누적 적으로 나타났고, 아황산가스의 등농도 곡선으로 콩의 수량감소 예측이 가능하였다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.711-711
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• 2009

Global warming has been widely recognized as a serious problem threatening the future of human beings. It is caused by the buildup in the atmosphere of greenhouse gases, such as carbon dioxide, methane, hydrofluorocarbons (HFCs), and sulfur hexafluoride (SF6). Particularly, SF6 has extremely high global warming potential compare to those of other global warming gases. One option for mitigating this greenhouse gas is the development of an effective process for capturing and separating these gases from anthropogenic sources. In general, gas hydrates can be formed under high pressure and low temperature. However, SF6 gas is known to form hydrate under relatively milder conditions. Therefore, technological and economical effects could be expected for the separation of SF6 gas from waste gas mixtures. In this study, we carried out morphological study for the SF6 hydrate crystals to understand its formation and growth mechanisms. The observations were made in high-pressure optical cell charged with liquid water and SF6 gas at constant pressure and temperature. Initially SF6 hydrate formed at the surface between gas and liquid regions, and then subsequent dendrite crystals grew at the wall above the gas/water interface. The visual observations of crystal nucleation, migration, growth and interference were reported. The detailed growth characteristics of SF6 hydrate crystals were discussed in this study.

• 공업화학
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• 제19권1호
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• pp.31-36
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• 2008

혐기성소화가스(ADG)를 원료로 수소를 제조하여 연료전지에 활용할 경우 ADG에 포함된 황화합물이 개질기의 촉매와 연료전지의 전극에 독으로 작용하므로 금속이온이 담지된 활성탄을 이용하여 황화합물을 제거하였다. 수분과 산소농도에 따라 고정층 흡착량이 변화하였으며, 산소 0.2 vol%, RH 90% 이상일 때 가장 높은 흡착량을 나타내었다. 본 연구에서는 KI 첨착한 활성탄에서 황화합물의 흡착특성을 고정층에서 동특성 실험을 통해 관찰하고 그 결과를 기준으로 흡착탑을 설계 제작 현장실험을 실시하였다.

• 상하수도학회지
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• 제14권3호
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• pp.271-280
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• 2000

This study was conducted to determine the applicable loading rate and to evaluate the possibility of using limestones as an alkalinity source for the removal of ${NO_3}^{-}-N$ remaining after denitrification/nitrification process with the down-flow sulfur packed bed reactor(SPBR). The pretreated sewage was fed to SPBR. Three SPBRs were filled with elemental sulfur particles and limestones and the volumetric ratios of sulfur to limestone were 0%, 12.5% and 25% for R-0%, R-12.5% and R-25%, respectively. The applicable loading rate was evaluated increasing flow rate with influent ${NO_3}^{-}-N$ concentration of 20 mg/L. For R-0% with external alkalinity supply, denitrification efficiency was greater than 96% up to loading rate of $354.8g\;{NO_3}^{-}-N/m^3{\cdot}day$, and corresponding EBCT was 1.4hr. For R-12.5% and R-25%, where alkalinity was supplied by the limestone filled in the reactor, denitrification efficiency was greater than 94% up to loading rate of $283.8g\;{NO_3}^{-}-N/m^3{\cdot}day$, and corresponding EBCT was 1.7hr. The slightly better performance of R-12.5 compared to R-25 suggests that the volumetric sulfur to limestone ratio of 12.5% was enough for the supply of alkalinity required for sulfur-utilizing denitrification. DO was appeared not showing inhibitory effect on sulfur-utilizing denitrification. The clogging of SPBR caused by the produced gas can effectively be eliminated by regular introduction of treated water in up-flow mode.