• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.257-257
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• 2013

In order to selectively remove oil and organic compound from water, silica nanoparticles with hydrophobic coating was used. Since silica nanoparticles are generally hydrophilic, removal efficiency of oil and organic compound, such as toluene, in water can be decreased due to competitive adsorption with water. In order to increase the removal efficiency of oil and toluene, hydrophobic polydimethylsiloxane (PDMS) was coated on silica nanoparticles in the form of thin film. Hydrophobic property of the PDMS-coated silica nanoparticles and hydrophilic silica nanoparticles were easily confirmed by putting it in the water, hydrophilic particle sinks but hydrophobic particle floats. PDMS coated silica nanoparticles were dispersed on a slide glass with epoxy glue on and the water contact angle on the surface was determined to be over $150^{\circ}$, which is called superhydrophobic. FT-IR spectroscopy was used to check the functional group on silica nanoparticle surface before and after PDMS coating. Then, PDMS coated silica nanoparticles were used to selectively remove oil and toluene from water, respectively. It was demonstrated that PDMS coated nanoaprticles selectively aggregates with oil and toluene in the water and floats in the form of gel and this gel remained floating over 7 days. Furthermore, column filled with hydrophobic PDMS coated silica nanoparticles and hydrophilic porous silica was prepared and tested for simultaneous removal of water-soluble and organic pollutant from water. PDMS coated silica nanoparticles have strong resistibility for water and has affinity for oil and organic compound removal. Therefore PDMS-coated silica nanoparticles can be applied in separating oil or organic solvents from water.

• 자원리싸이클링
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• 제29권6호
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• pp.57-64
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• 2020

본 연구에서는 LCD 터치 패널 유리의 재활용을 위해 기계적 방법과 화학적 용해법을 혼용하여 OCA 및 유기 불순물을 제거하는 실험을 진행하였다. 터치 패널의 기계적 파분쇄를 위해 cut mill과 oscillation mill을 이용하였으며, OCA와 유기 불순물의 제거를 위해 물, 에탄올, 디클로로메탄을 이용하여 터치 패널 파쇄물을 세정하였다. 세정 이후 TGA를 통해 유기 불순물의 제거 효율을 평가한 결과 디클로로메탄 단일 용매를 사용한 경우 세정 효과가 가장 뛰어났으며, 세정 온도가 증가함에 따라 유기 불순물의 제거 효과가 증가함을 확인하였다. 제타 전위 측정을 통해 터치 패널 유리 파쇄물의 용매 내 분산도를 평가한 결과, 세정 효과가 가장 낮은 물의 제타 전위 절대값이 타용매에 비해 낮았으며, 유기물의 제거 효과는 화학적인 용해 특성뿐 아니라 용매 내 물리적인 분산 특성에 의해서도 영향을 받을 수 있음을 확인하였다.

• 한국해양생명과학회지
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• 제3권1호
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• pp.38-43
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• 2018

대형저서동물에서 우점하고 있는 갯지렁이류는 퇴적층의 유기물 섭취를 통하여 저질환경개선에 중요한 역할을 한다. 본 연구에서는 최근 양식기술이 개발된 바위털갯지렁이를 이용하여 갯벌 퇴적층의 유기물 제거효과를 검토하였다. 이를 위하여 입자특성이 다른 세종류의 저질환경(S1: 강사질, S2: 해사질, S3: 니사질)에서 해수 및 퇴적층의 TOC를 측정하였다. 바위털갯지렁이는 세종류의 입자특성에서 모두 유기물 제거효과를 나타내었으며, 입자가 클수록 제거율이 높았다. 유기물 정화능력을 정량적으로 평가한 결과 바위털갯지렁이는 각 저질별로 강사질에서 3.9856 ppm g^-1d^-1, 해사질에서 2.8021 ppm g^-1d^-1, 그리고 니사질에서 28.1142 ppm g^-1d^-1의 제거능력을 나타내었다. 본 연구결과는 바위털갯지렁이가 다양한 저질에서 유기물 제거에 기여하고 있음을 보여 주었다.

• 한국물환경학회지
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• 제39권6호
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• pp.465-474
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• 2023

The chemical composition and molecular weight characteristics of dissolved organic matter (DOM) exert a profound influence on the efficiency of organic matter removal in water treatment systems, acting as efficiency predictive indicators. This research evaluated the primary chemical and molecular weight properties of DOM derived from diverse sources, including rivers, lakes, and biomasses, and assessed their relationship with the efficiency of coagulation/flocculation treatments. Dissolved organic carbon (DOC) removal efficiency through coagulation/flocculation exhibited significant correlations with DOM's hydrophobic distribution, the ratio of humic-like to protein-like fluorescence, and the molecular weight associated with humic substances (HS). These findings suggest that the DOC removal rate in coagulation/flocculation processes is enhanced by a higher presence of HS in DOM, an increased influence of externally sourced DOM, and more presence of high molecular weight compounds. The results of this study further posit that the efficacy of water treatment processes can be more accurately predicted when considering multiple DOM characteristics rather than relying on a singular trait. Based on major results from this study, a predictive model for DOC removal efficiency by coagulation/flocculation was formulated as: 24.3 - 7.83 × (fluorescence index) + 0.089 × (hydrophilic distribution) + 0.102 × (HS molecular weight). This proposed model, coupled with supplementary monitoring of influent organic matter, has the potential to enhance the design and predictive accuracy for coagulation/flocculation treatments targeting DOC removal in future applications.

• 한국환경보건학회지
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• 제34권6호
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• pp.446-451
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• 2008

In this study, the removal characteristics of organic components and nutrients of sewage taken from the Suwon area were investigated in a lab-scale modified DNR (Daewoo Nutrient Removal) process. The modified DNR process consisted of a sludge denitrification tank, an anaerobic tank, an anoxic tank, an aerobic tank, a secondary anoxic tank and a secondary aerobic tank. The proposed process with the average C/N ratio of 3.5 was performed for the sewage treatment. The results were compared with other existing DNR processes. The organic fractions in sewage were analyzed by measuring the oxygen uptake rate. The resulting removal efficiencies of SS, BOD, COD, TN and TP were 93.1%, 95.5%, 86.1%, 67.8% and 80.6%, respectively.

• 환경위생공학
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• 제17권3호
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• pp.46-51
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• 2002

This study was performed to treat a sewage at the upper stream of dam using modified sequencing batch reactor, During the operating period, average $COD_{cr}$, removal efficiency was about 85% but average T-N and ${PO_4}^{3-}-P$ removal efficiencies were 43% and 30% respectively. Because the organic matter was very low compared with nitrogen and phosphorous in influent($BOD_{5}/{NH_4}^{+}-N{\;}={\;}2,{\;}BOD_{5}/{PO_4}^{3-}-P{\;}={\;}15.6$), nitrogen and phosphorus removal efficiency was relatively low. Average nitrogen removal efficiency was 50 % at $10^{\circ}C$ or above and it was 36 % at $10^{\circ}C$ or below. As reactor was located in outdoor without any thermostat, temperature decreased at least $2.4^{\circ}C$ in the winter season. Therefore, if we would apply this modified sequencing batch reactor to sewage which concentration of organic matter was very low compared with nitrogen and phosphorous, we have to addition of external carbon and installation of any thermostat.

• 환경위생공학
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• 제24권3호
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• pp.7-15
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• 2009

본 연구에서는 DEPHANOX공정을 변형한 두 개의 질산화 반응조를 둔 M-DEPHANOX 공정과 기존 변형된 질산화 반응조를 RBC로 대체한 형태로 단일 질산화 반응조로 운전된 M-DEPHANOX 공정을 운전하였다. 그리고 두 공정의 제거율을 비교하기 위하여 질소, 인 및 유기물 제거율과 질산화 반응조의 유기물 부하에 따른 $NH_3$-N 제거율을 조사하였다. 연구결과 $NH_3$-N 제거율은 M-DEPHANOX공정이 91.8%, M-eBNR 공정은 96.9%로서 두 공정 모두 높게 나타났다. TCOD와 SCOD 제거율은 M-DEPHANOX공정은 84.1와 78.2%, M-eBNR공정은 83.4%와 75.6%이었다. 또한 유기물이 $NH_3$-N 제거율에 미치는 영향은 M-eBNR 공정의 질산화 반응조에서는 1차 침전조에서 거의 나타나지 않았다. M-eBNR 공정의 $NH_3$-N 제거율은 도시하수의 유입성상이 달라지더라도 안정적으로 유지되었다.

• 상하수도학회지
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• 제18권2호
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• pp.208-214
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• 2004

Dissolved air flotation (DAF) is an effective solid/liquid separation process for low density floc particles such as algal, color-alum and clay-alum flocs produced from low turbidity water. The removal of taste and odor-causing organics (2-mthylisoboneol and geosmin) originating from algae in drinking water is a local and worldwide concern. Although DAF has been effectively applied for the removal of suspended solid, its application for the treatment of dissolved organic carbon is very limited. In this study, a new hybrid system consisting of adsorption and DAF processes was introduced for the simultaneous removal of algae and taste and odor-causing organics. Powdered activated carbon (PAC) was used as an adsorbent. In this proposed system, the major concern of eliminating the spent PAC from the system was also addressed. It was found that zeta potential of algae and PAC was increased with coagulant dosage, and the removal efficiency in DAF was also enhanced up to 90~95% under the given experimental conditions. Based on this study, the hybrid process was found to be a promising technology for the simultaneous removal of algae and dissolved organic pollutants.

• 산업기술연구
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• 제29권A호
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• pp.83-88
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• 2009

The removal efficiency of organic compounds and the toxicity evaluation of microorganism have been studied in dye wastewater treatment using $UV/TiO_2$ and $UV/H_2O_2$ photooxidation system. Sample waters tested in this work were raw dye wastewater and dye wastewater treated in $UV/TiO_2$ and $UV/H_2O_2$ photooxidation system respectively. Total organic carbon(TOC) removal rate was 50% in $UV/TiO_2$ process and 80% in $UV/H_2O_2$ process. It has been investigated with colony counting agar method and paper disk method whether the type of treatment process has affected the microorganism growth. In the raw wastewater, more than four types of microorganisms have survived. But, little of microorganisms were alive at TOC removal rate of 50% in $UV/TiO_2$ system. In contrast to that, two types of microorganisms were found at TOC removal rate of 80% in $UV/H_2O_2$ system.

• 대한환경공학회지
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• 제35권5호
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• pp.381-387
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• 2013

UASB-ABF (Up-flow anaerobic sludge blanket-aerated bio-filter) 시스템을 이용한 하수의 혐기성처리 방법에서 질소와 인을 제거하는 공법에 대하여 연구하였다. 160일간의 UASB-ABF 시스템을 운영한 결과 유출수 반송을 통하여 TCOD뿐만 아니라, TN과 TP를 효율적으로 제거할 수 있었다. 무반송의 경우 UASB 반응조에서 유기물 제거효율은 64%에 머물었으나, 반송률 120%, 180%, 240%로 증가한 결과 각각 92%, 95%, 96%로 향상되었다. 반송률 180% 이상에서는 유기물 제거효율 증가폭은 크지 않았다. ABF 유출수 반송으로 TN 제거효율이 크게 향상되었다. TN 제거효율은 무반송 조건일 때 18%에서 82%로 향상되었으며, UASB에서 지속적인 유기물질 제거로 인하여 ABF에서 질산화효율은 안정적으로 95% 이상으로 타나났다. ABF 유출수 반송으로 TP 및 $PO{_4}^{3-}$-P 제거효율이 모두 향상되었다. TP의 경우 무반송에서는 거의 제거되지 않았으나, 반송률이 120%, 180%, 240%에서는 각각 51%, 63%, 71%로 향상되었고, 주로 UASB에서 제거되었다.