• 한국진공학회지
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• 제14권3호
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• pp.165-170
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• 2005

의료용 임플랜트의 혈액적합성 개선을 위하여 박막코팅에 대한 관심이 증대하고 있다. 특히 diamond-like carbon(DLC)과 titanium nitride(TiN) 박막은 우수한 화학, 물리적 성질은 물론 생체적합 특성까지 갖추고 있다. 따라서 이들 박막의 혈액 적합성과 물리적 특성과의 관개를 연구하기 위하여 박막표면의 모폴로지 및 젖음성과 fibrinogen흡착 특성을 비교 분석하였다. 혈액응고 원인이 되는 fibrinogen의 흡착량은 DLC보다 TiN의 경우가 적어, 보다 우수한 특성을 보였으며, 이것은 TiN박막 표면의 높은 친수성으로 인한 것으로 판단된다. 박막표면의 fibrinogen 흡착을 줄이기 위해 플라즈마 처리 및 노(爐) 열처리를 각각 수행하였다. 산소 플라즈마 및 열처리를 하였을 경우 DLC 박막은 큰 효과가 없는 반면 TiN 박막의 경우 fibrinogen 흡착량이 크게 줄어 보다 개선된 결과를 보였다.

• 에너지공학
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• 제14권2호
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• pp.133-139
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• 2005

도장공정에서 발생하는 VOC의 처리를 위한 활성탄-광촉매 복합시스템을 제안하였고, VOC제거성능을 실험적으로 평가하였다. 활성탄 합은 톨루엔 흡착특성에 근거하여 설계하였고, 광촉매 시스템은 $TiO_2/SiO_2$ 유동층 반응기와 $TiO_2$코팅된 필터의 연계시스템으로 설계하였다. 본 활성탄-광촉매 복합시스템은 서로 다른 VOC 화학종 및 농도에 따라 $75\~100\%$에 이르는 VOC제거효율을 보여주었다.

• 한국대기환경학회지
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• 제19권4호
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• pp.363-376
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• 2003

In this study, the fugitive emission characteristics of airborne volatile organic compounds from different source categories were evaluated with respect to the concentrations measured in the vicinity of the sources. A total of 22 different sources were investigated, including gasoline storage and filling stations, painting spray booth, laundry, printing officer, textile industries, and a number of environmental sanitary facilities such as landfill, wastewater treatment and incineration plants. The target VOCs included 83 individual compounds, which were determined by adsorption sampling and thermal desorption coupled with GC/MS analysis. Overall, the aliphatic compounds appeared to be the most abundant class of compounds in terms of their concentrations, followed by aromatic, and halogenated hydrocarbons. As a single compound, however, toluene was the most abundant one, explaining 11% of the total VOC concentrations as an average of all the dataset. Among source categories, petroleum associated sources such as gasoline storage/filling stations, and laundry factory were identified as the most significant sources of aliphatic hydrocarbons, while aromatic VOCs were dominantly emitted from the sources handling organic solvents, such as painting booth, printing offices, and textile dyeing processes. However. there was no apparent pattern in terms of the contributions of eath group to the total VOCs concentrations in environmental sanitary facilities. It was also found that the activated carbon adsorption tower installed for the VOC emission control in some facilities do not show any effective performances, which may result in the increased VOC levels in the ambient atmosphere.

• 상하수도학회지
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• 제10권4호
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• pp.94-102
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• 1996

This study was accomplished to get the basic data for the optimum chemical feed, evaluating interference between tastes and odors chemicals and coagulants in existing water treatment processes. During the tastes and odors occurs at D intaking tower area in 1995, PAC(Powdered Activated Carbon) feed with coagulants was PAC feed only and with coagulant simultaneously were appeared TON removal efficiency about 84%-87% within 20 min reaction time, but feed with time intervals was about 98% TON removal efficiency. Therefore in the case of PAC feed with coagulant, it is effective to feed coagulant on some time intervals in removing tastes and odors. It is not effective to feed PAC with chlorine dioxide($ClO_2$) or chlorine simultaneously in removing tastes and odors, because these chemicals were reduced the adsorption capacity of PAC.

• 대한토목학회논문집
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• 제43권4호
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• pp.449-458
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• 2023

용존 유기물을 흡착 제거하는 기술로서, 흡착능이 우수한 입상활성탄을 우선적으로 적용할 수 있지만, 흡착탑의 운전기간에 따라 GAC의 흡착능이 현저히 저하되어 파과되는 한계가 있으며 파과된 활성탄인 spent-GAC는 교체나 재생이 불가피하다. 활성탄 교체는 비용의 경제성 때문에 기피되며 상업적으로 열재생법을 사용하고 있으나, 800℃ 이상의 고온 조건으로 인한 높은 에너지 비용과 활성탄의 질량 손실이 발생하는 단점이 있다. 본 연구에서는 CSOs내의 용존 유기물 처리에 사용된 spent-GAC의 재생효율을 제고하기 위해, Fenton 산화법과 초음파 산화를 융합한 다중산화기술인 Sono-Fenton 방법을 적용하였고, 산화제 주입농도와 초음파 주파수별 spent-GAC의 재생효율을 조사하였다. 적용된 Sono-Fenton 처리에서 Fe²⁺ 10 mmol/L, H₂O₂ 농도 1,000 mmol/L, 120분 초음파 주사시간, 초음파 주파수 40 kHz 재생처리 조건에서 68.5%의 가장 높은 재생효율을 얻을 수 있었고, 750 kHz에서도 유사한 효율을 얻을 수 있었으며, 다른 주파수의 초음파는 재생효율이 불량했고 주파수의 크기와 GAC 재생효율은 선형 관계를 나타내지 않았다. 실 하수를 희석하여 제조한 CSOs로 GAC 흡착탑을 연속운전 한 경우, 재생없이 700시간 내외의 운전이 가능했고 1회의 Sono-Fenton 처리를 적용한 결과, 총 1,000시간의 GAC 흡착 운전 기간 동안 40~70%의 COD_cr 제거 효율이 확보하였다.

• 청정기술
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• 제23권3호
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• pp.286-293
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• 2017

본 연구는 악취가스 물질(바이오가스의 불순물)의 하나인 $H_2S$를 제거하기 위한 흡착제의 성능을 향상시키기 위해 수행하였다. 기본 담체로서 4가지 물질($Fe_2O_3$, $Ca(OH)_2$, 분말 활성탄, $Al(OH)_3)$을 혼합 사용하여 pellet 형태의 흡착제를 제조하였다. 또한, 4가지 물질의 $H_2S$ 흡착에 미치는 영향을 평가한 결과, $Fe_2O_3$와 분말활성탄은 $H_2S$ 흡착성능이 각각 1.5, 2배로 증가하는 것으로 나타났으며 $Ca(OH)_2$와 $Al(OH)_2$는 $H_2S$ 흡착성능에는 영향이 없는 것으로 나타났다. 또한 4가지 물질을 기본혼합 담체로 한 후, 활성물질로 KI, KOH, $K_2CO_3$를 선정하여 각각 5 wt% 첨가한 후에 $H_2S$ 흡착성능을 시험한 결과 $K_2CO_3$를 첨가한 흡착제가 가장 성능이 우수한 것으로 나타났다. 또한 $K_2CO_3$를 5 ~ 30 wt%까지 변화시키면서 흡착성능을 확인한 결과, $K_2CO_3$ 함량이 20 wt%까지는 함량과 비례하여 $H_2S$ 흡착성능이 증가하는 것을 확인할 수 있었으나 30 wt%에서는 $H_2S$ 흡착성능 급격히 떨어지는 것을 확인하였다. 또한 $K_2CO_3$ 첨가 함량에 따른 $H_2S$ 흡착성능을 바탕으로 Thomas model을 이용하여 모델링을 실시한 결과에서도 $K_2CO_3$ 함량이 20 wt%까지는 실험값과 모사값이 잘 일치하고 있음을 보여주었다. 이러한 결과들을 바탕으로, 본 연구에서 확인된 활성물질의 종류와 활성물질의 함량을 흡착제 제조에 이용한다면 $H_2S$ 흡착제의 흡착성능 개선뿐만 아니라 흡착제의 사용수명 증대를 기대할 수 있었다.

• 상하수도학회지
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• 제21권3호
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• pp.341-348
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• 2007

The efficiency of powdered activated carbon (PAC) for removing taste and odor (T&O) in drinking water supplies is dependent on the contact time, quality of mixing, and the presence of competing compounds. All of these are strongly influenced by the stage in the treatment process at which the PAC is added. In conventional water treatment plants (WTPs), PAC is commonly added into the rapid mixing basin where chemicals such as coagulants, alkaline chemicals, and chlorine, are simultaneously applied. In order to prevent interference between PAC and other water treatment chemicals, alternative locations for addition of PAC, such as at transmission pipe in the water intake tower or into a separated PAC contactor, were investigated. Whatever the location, addition of PAC apart from other water treatment chemicals was more effective for geosmin removal than simultaneous addition. Among several combinations, the sequence 'chlorine-PAC-coagulant' produced the best result with respect to geosmin removal efficiency. Consequently, when PAC has to be applied to cope with T&O problems in conventional WTPs, it is very important to prevent interference with other water treatment chemicals, such as chlorine and coagulant. Adequate contact time should also be given for adsorption of the T&O compounds onto the PAC. To satisfy these conditions, installation of a separated PAC contactor would be the superior alternative if there is space available in the WTP. If necessary, PAC could be added at transmission pipe in the water intake tower and still provide some benefit for T&O treatment.

• 청정기술
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• 제28권4호
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• pp.285-292
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• 2022

대기 오염의 주요 원인인 휘발성유기화합물(VOCs)의 배출을 저감 하기 위한 방법으로 주로 활성탄 흡착탑이 활용되고 있다. 하지만 활성탄의 짧은 수명과 잦은 교체 주기의 단점이 있어 이를 극복하기 위한 다양한 기술이 개발되고 있으며, 광촉매-활성탄 복합체는 이러한 활성탄의 단점을 극복할 수 있는 방법임을 입증하였다. 광촉매-활성탄 복합체는 활성탄 표면에 금속산화물 광촉매를 코팅하여 광촉매 효과와 활성탄의 흡착능력 효과를 동시에 확보할 수 있는 휘발성유기화합물 저감 물질이다. 미세유체공정을 이용하여 ZnO, 은(Ag) 나노입자를 동시에 합성한 후 실시간으로 ZnO와 은(Ag) 나노입자 용액을 활성탄이 채워진 충진층 반응기에 주입하여 Ag-ZnO 활성탄 복합체를 합성하였다. 합성 반응시간에 따른 광촉매 복합체의 증착양을 분석했으며, 다양한 분석 방법을 통해 광촉매가 활성탄의 기공을 막지 않고 활성탄 표면에 선택적으로 증착 되었음을 확인하였다. 톨루엔 가스백 시험과 흡착 파괴시간 시험을 통해 광촉매-활성탄 복합체가 순수한 활성탄보다 우수한 저감 효과와 지속성을 가지는 것을 확인하였다. 본 연구를 통해 개발된 공정은 광촉매-활성탄 복합체를 효율적으로 생산할 수 있는 방법으로 대량 생산을 위한 스케일 업 공정을 통해 국내의 VOCs 저감 물질 가격 경쟁력을 높일 수 있을 것으로 사료된다.

• Journal of Korean Society for Atmospheric Environment
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• 제15권E호
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• pp.29-38
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• 1999

This study identified emission sources and emissions of air pollutants such as volatile organic compounds (VOCs), solvents, and acid gases produced from chemical plants. We collected air samples from various processes, reactors and facilities using VOC detectors and workers' experience. We identified chemical structures and emission concentrations of air pollutants. We analyzed total emissions of air pollutants emitted from the chemical plants. Also, we developed some emission reduction technologies based on chemical types and emission situations of the identified air pollutants. For reduction of air emissions of acid gases, we employed a method improving solubility of pollutants by reducing scrubber operation temperature, increasing surface area for effective contact of gas and liquid, and modifying or changing chemicals used in the acid scrubbers. In order to reduce air emissions of both amines and acid gases, which have had different emission sources each other but treated by one scrubber, we first could separate gas components. And then different control techniques based on components of pollutants were applied to the emission sources. That is, we first applied condensation and then acid scrubbing method using H2SO4 solution for amine treatment. However, we only used an acid scrubbing method using H2O and NaOH solution for acid gas treatment. In order to reduce air emissions of solvents such as dimethylformamide and toluene, we applied condensation and activated carbon adsorption. In order to reduce air emissions of mixture gases containing acid gases and slovents, which could not be separated in the processes, we employed a combination of various air pollution control devices. That is, the mixture gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower in sequence. In addition, for improvement of condensation efficiency of VOCs, we changed the type of the condensers attached in the reactors as a control device modification. Finally, we could successfully reduce air emissions of pollutants produced from various chenmical processes or facilities by use of proper control methods according to the types and specific emission situations of pollutants.

• 한국염색가공학회지
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• 제35권4호
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• pp.256-273
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• 2023

Among the dyeing industries, the tenter process is a process that improves the quality of fibers by drying and ironing (heat treatment) dyed fabrics, and drugs such as water repellents, antistatic agents, and fiber softeners are mainly used in these tenter processes. These drugs are vaporized in the process of treatment by high temperatures (180 ~ 230℃), and are observed in a complex form such as white smoke, oil mist, and fine dust, causing odor. To treat the complex exhaust gas at the rear end of the tenter facility, most companies operate by installing a wet scrubber and an adsorption tower alone or in parallel, but there are many problems. In particular, the insoluble oil mist at the rear end of the tenter has significantly low processing efficiency in the cleaning dust collection facility, and there is a problem in the facility by adsorption due to the occlusion phenomenon caused by the oil mist. In addition, the odor gas at the rear end of the tenter contains a lot of aldehydes, and in order to improve these various problems, a complex exhaust purification device using cyclone and electric support collector was developed. This study examined the applicability of economical and efficient technology by removing complex air pollution at the rear end of the tenter and applying improved technology than the existing technology.