• 청정기술
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• 제3권2호
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• pp.28-30
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• 1997

발효 아미노산을 분리하는 기존의 공정인 이온교환법에서 폐액 및 폐수처리에 따른 문제점을 해결하기 위한 새로운 분리공정으로 탈염 전기투석과 Water-splitting Electrodiaysis를 이용한 발효 아미노산의 분리 가능성 및 다양한 cell configuration과 막에 대한 성능 실험을 실시하였다. 실험결과 전기투석에 의해 경도물질을 제거한 후 양이온교환막과 bipolar 막으로 구성된 2-compartment WSED로 효과적으로 발효액에서 아미노산을 분리 할 수 있었으나 1가 양이온에 선택성을 지닌 양이온교환막으로는 아미노산의 분리가 어려움을 알 수 있었다.

• 청정기술
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• 제9권1호
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• pp.37-42
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• 2003

Biofiltration was successfully applied to treat a mixture of volatile organic compounds(benzene, xylene) from contaminated air stream. Immobilized Ps. oleovorans biofilter was evaluated for its value in simultaneous removal of benzene and xylene from waste air stream. The variety of operating conditions were tested to evaluate important factors such as space velocity, pH, water content, etc.

• 청정기술
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• 제3권2호
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• pp.74-86
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• 1997

최근 청정기술의 필요성이 증가하면서 막분리 공정에 의한 산업폐수 처리기술에 대한 관심이 높아가고 있다. 이 연구는 중화법과 water-splitting electrodialysis (WSED)를 이용하여 금속을 포함하고 있는 폐수에서 유용한 물질을 회수하고 무방류계를 실현하기 위한 것이다. 본 연구에서는 산폐수와 혼합폐수 처리의 공정 설계를 위한 공정의 흐름를 확립하였고, 이 공정에 따른 물질수지를 계산하였다. 또한 주요 단위공정인 침전조와 산회수공정의 운전인자에 대한 실험을 수행하였다. 침전공정에서는 KOH와 NaOH를 중화제로 이용하여 pH에 따른 침전효율과 슬러지양을 비교하였으며 산회수 공정에서는 KCl과 NaCl을 합성원료로 이용하여 WSED의 막구조에 따른 회수효율을 조사하였다.

• 청정기술
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• 제29권4호
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• pp.321-326
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• 2023

최근 탄소중립과 관련하여 연소 시 이산화탄소 배출이 없어 청정한 수소에너지에 대한 관심이 증가하고 있다. 이에 따라 수소 생산에 관련된 연구가 계속되고 있으며 본 연구에서는 폐기물을 처리함과 동시에 고순도 수소를 생산하기 위해 폐기물 유래 합성가스를 수성가스전이반응에 적용하였다. 마그네슘을 세륨과 함께 지지체로 사용하여 고온수성가스전이(HT-WGS)반응에서 촉매의 활성을 향상시키고자 하였다. HT-WGS 반응의 활성물질로 구리를 사용해 Cu-CeO₂-MgO 촉매를 제조하였으며, 제조방법에 따른 촉매활성 연구를 진행하였다. HT-WGS 반응 결과 함침법으로 제조된 Cu-CeO₂-MgO 촉매가 가장 높은 활성을 보였으며, 이는 가장 높은 산소 저장능과 많은 활성 Cu 종을 가지는 특성에 기인한 결과이다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.85-92
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• 2002

When the United Nation classified as Korea is the one of the water deficit country. The consensus was made that the water is the one of the precious national resources. Government increases their R/D budget trying to get more clean water bodies. For instances, 'Sustainable Water Resources Development' project is the one of major title in '21 Century Frontier Research project and there are several small research projects are undergoing by the Ministry of Agriculture and KARICO. However, when the environmental preservation issue has been get more emphasis, construction of the Surface Dam met the blockage from the environmentalists due to the problem of the their water buried area. Since the most fitting site for surface dam had been used in the past, some engineer move their focus on modification of the existing Dam's height to enlarge its capacity or dredging the bottom of the reservoir recently However dredging evoke water quality problem in return by accumulated materials at the bottom. Last year the Dong Gang Dam plan has been canceled by environmental problem in water buried area of the reservoir. With the point of this view, ground water gets more focus for the one of the useful alternative for clean water bodies. Underground dam technique which had widely applied once in the early nineteen eighties by the KARICO and attenuated due to engineering insufficiency. The technique is newly studied with the advanced engineering technique. Still groundwater usage rate in Korea is much lower comparing with the advanced countries and has many rooms to develop. Wells, under ground dam and radial collector wells are typical facilities up to now. There is little application in Korea for the Recharge Dam, which had been widely used in the advanced countries. The Recharge Dam is technique to conjunct surface water and groundwater body together, This technique had developed to increase groundwater recharge at the beginning This research is the result of the study on the possibility of the development of the new technology, Groundwater Reservoir' which was modified from Recharge Dam. Groundwater Reservoir is like a deep artificial lakes trenched in hard rock aquifer to get groundwater. The advantage of the Groundwater Reservoir is followings 1) It can be developed at the plains area, not in the deep valley 2) Huge water body can be developed without dam 3) Small buried area comparing surface water dam makes the least environmental effect. 4) Trenching cost can be substitute by the income of the selling rock debris 5) Outfit of the reservoir can be modified to match with the site prospect 6) Rock debris can be used as constructing materials 7) It can be used as groundwater recharge system when the heavy rains comes 8) The reservoir looks like scenery lake with huge clean water bodies.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2004년도 춘계학술대회 발표 논문집
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• pp.118-122
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• 2004

본 연구에서는 반도체 세정 챔버 내부에서 회전 척을 사용하는 기판의 세정 공정에서 세정장치와 건조장치를 분리하지 알고 일체화하는 기술을 연구하는 한편, 초음파 세정기술을 이용하여, 세정에 사용되는 약액을 절감하는 방법도 연구하였다. UWA(Ultrasonic Water and Clean Air) system은 초음파 진동부, 초순수 공급부 그리고 clean air공급부를 모듈화 하였다. UWA system으로 공급된 초순수에 70～130kHz범위의 초음파가 더하여지고 반도체 기판 위에 분사되면 기판 위의 미세 파티클을 세정하는 효과를 갖는다. 세정 후 연속적으로 clean air를 분사하여 기판 위의 수분을 완전히 제거한다. Particle 세정 작업을 실시한 후 표면을 검사하여 정밀세정 능력을 확인하였다.

• 한국태양에너지학회 논문집
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• 제27권3호
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• pp.37-44
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• 2007

For the past few years, the concern for clean energy has been greatly increased. Ocean Thermal Energy Conversion(OTEC) power plants are studied as a viable option for the supply of clean energy. In this paper, the thermodynamic performance of OTEC cycle was examined. Computer simulation programs were developed under the same condition and various working fluids for closed Rankine cycle, regeneration cycle, Kalina cycle, open cycle and hybrid cycle. The results show that the regeneration cycle using R125 showed a 0.17 to 1.56% increase in energy efficiency, and simple Rankine cycle can generate electricity when the difference in warm and cold sea water inlet temperatures are greater than $15^{\circ}C$. Also, the cycle efficiency of OTEC power plant using the condenser effluent from nuclear power plant instead of the surface water increased about 2%.

• 동력기계공학회지
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• 제21권3호
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• pp.74-84
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• 2017

This paper presents the development of the underwater cleaning robot platform for a higher efficiency in manufacturing industry. Human operators directly go into the cistern and clean sludge after drainage of the water so far. It is sometimes dangerous because of the harmful chemical materials from the product making process. In addition, it takes long time for water drainage and supplying it back. However, the robot cleaning operation does not need to drain water so that it could be applied to the sludge cleaning work at any time without the plant pause. Moreover, it can prevent the safety accidents because human operators are not necessary to enter directly the sludge cisterns. This paper shows the performance of cleaning work that can be applied in the industrial field through the design and development of underwater cleaning robot platform. And these results demonstrate that the developed underwater cleaning robot has great possibilities to clean other industrial water cisterns.

• 한국물환경학회지
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• 제22권4호
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• pp.639-647
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• 2006

The temperature effect at $20^{\circ}$ and $10^{\circ}$ on the nutrient removal efficiency was evaluated in the combined biological nutrient removal system (CBNR) with anaerobic-intermittent aerobic-oxic reactors. The test was conducted under the conditions of various ratios of intermittent aeration time and distribution of influent raw water to CBNR. The removal efficiencies of organics, nitrogen and phosphorus were a little bit better at $20^{\circ}$ than at $10^{\circ}$. However the large difference of temperature effect on the nutrient removal efficiency between $20^{\circ}$ and $10^{\circ}$ was not appeared because of highly sustained MLSS concentrations in the reactors and controlled intermittent aeration time. In the removal of phosphorus, Mode III (50/70 min in aeration on/off time, 3 times of intermittent aeration) showed more effective compared with short aeration time of Mode IV. In case of N, P removal, the denitrification rate was lower in Mode A with splitted inflow into anaerobic and intermittent aeration basins than in Mode B with sole inflow into anaerobic basin.

• 청정기술
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• 제8권2호
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• pp.67-76
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• 2002

Dewatered sludge of 400,000t/y from water treatment plants in Korea is being disposed through landfill and ocean dumping. However, the disposal is posing more and more serious environmental problems at the same time not only because of landfill site shortage in municipal suburbs, but because of the concern it will contaminate the oceans. In this study, the research on utilizing the sludge dried by flash dryer as covering soil in the landfill sites was carried out to solve these problems on environmental affinity. Both dewatered and dried sludge were exposed to the natural condition and observed according to the atmospheric changes. An experiment of soil engineering characteristics of the dried sludge and tests on mixed sludge(silty sandy soil : dried sludge = 10:90 ~ 30:70) such as particle size distribution, liquid and plastic limit, moisture content, specific gravity and compaction test were carried out. According to the compaction test, the compaction was confirmed as the optimum water content ratio was observed in the condition of SM-silty sand of particle size distribution, NP of liquid and plastic limit, 101.4% of moisture content, 2.04~2.12 of specific gravity. The results showed that dried sludges mixed with at least 30% of natural soil could be used as daily covering soil in the landfill sites.