• 청정기술
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• 제10권4호
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• pp.189-194
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• 2004

최근 환경부와 과학기술부에서 과학기술 분야의 효율적인 발전을 도모하고자 해당 기술분야의 기술지도를 마련하였다. 이를 위하여 산업기술동향을 분석한 후, 미래유망 기술 및 세계적 경쟁력을 확보할 수 있는 핵심기술 등이 도출되었고, 마련된 기술지도는 산 학 연 관의 전략적 연구 및 기술개발사업 추진에 방향성을 제시하고 있다. 여기에서는 최근 친환경공정기술과 관련한 분야로, 과학기술부 국가기술지도의 '환경/에너지 프론티어 진흥' 중 '환경친화적 소재/제품 및 공정기술' 부문과 환경부 차세대 핵심환경기술개발사업 10개년 종합계획의 '친환경 공정기술' 부문에서 작성된 기술지도 내용에서 무배출 기술 중심으로 살펴보았다. 그리고 해당 기술분야의 강점, 약점, 기회, 위협을 분석하고, 앞으로의 연구수행에 전략수립과 효율적인 발전에 기여하고자 하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.91-93
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• 2009

A large steel ingot needs to be larger and larger in size and an ultra high clean, no defect in quality with a low hot top ratio for the resent heavy industry. The demands are very difficult to achieve simultaneously because of their contradictive effect to each other in results. In this study, 30ton steel ingot was cast in a foundry with an optimized design parameter of cast mold and cast process conditions for the low hot top ratio, 12%. The cast ingot was analyzed in macro defect, segregations, and cleanness. No macro defect was founded in central surface of the ingot. The degree of segregation and cleanness are in the controlled range with a sound quality.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.442-447
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• 2006

In semiconductor manufacturing clean rooms, it becomes important to remove airborne molecular contaminants as well as particulate contaminant in outdoor air introduced into clean rooms. One suitable control technique for these chemical contaminants is air washing by water in an outdoor air handling unit. In order to enhance the removal efficiency of chemical contaminants the effect of adding a heating and humidifying process before an air washer was examined.

• 한국실내디자인학회논문집
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• 제20권5호
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• pp.178-187
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• 2011

This research suggested the hygienic spatial composition of sell-service restaurants applying HACCP(Hazard Analysis and Critical Control Point System). The circulation of the food, dishes, waste, workers and customers were each fractionated and arranged according to the hygienic sequence of cooking food in kitchen and process for eating food within the customer space. The spaces were separated by the degree of cleanness(clean area, semi-clean area, contaminated area). After that, hygiene facilities to remove contamination and pass facilities intended to control moving were added at the possible points of cross-contamination in oder to prevent the cross-contamination. For hygienic spatial composition of self-service restaurant, the following should be acknowledged: In the kitchen, spaces in which the food is handled after being heated should be located in the clean area. As of the customer space, spaces where dishes are prepared, food and water is received, and the table hall should be located in the clean area. Food circulation should flow from the contaminated area to the clean area. Food, dishes, waste should be moved through pass facilities so that workers do not have to come and go between other areas of cleanness. Also lockers for private clothes and lockers for uniforms should be separated. Hygiene facilities should be easily accessible so that workers can use them whenever they enter their working area. The contaminated area where dirty dishes are dealed with should be separated from the clean area. Waste should be thrown out without crossing cooking areas. As of customer circulation, the hygiene facility for hand washing should be located near the space where dishes for self-service are placed. The customer circulation should lead customers to leave restaurants after giving back the dirty dishes in the contaminated area.

• 청정기술
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• 제7권4호
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• pp.281-290
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• 2001

마이크로파를 이용하여 천연 게껍질로부터 키토산을 제조하는 공정에 대한 연구가 수행되었다. 본 연구의 주목적은 키토산을 제조함에 있어서 청정에너지원으로서 마이크로파의 효용성을 시험하고자 하는 것이다. 또한 기존의 염산을 사용하는 키토산 고분자의 올리고당화 가수분해 반응을 청정촉매인 인체 식용성 유기산으로 대체하는 공정도 연구되었다. 마이크로파는 반응시간을 줄이는데는 크게 효과적임을 알 수 있었다. 그러나, 반응시간 이외에 화학적 선택성 등의 부가적인 이점은 관찰하기 어려웠다. 키토산 고분자의 가수분해 반응에 본 연구에서 사용된 유기산은 매우 효과적임이 관찰되었다. 이러한 유기산의 촉매역할은 가압반응조건에서 더욱 두드러지게 나타났다. 예를 들어 300,000 이상의 분자량을 갖는 키토산 고분자는 $120^{\circ}C/1$시간의 가압반응을 통해서 거의 물에 가까운 점도를 갖는, 분자량이 매우 작은 키토산 올리고당으로 분해될 수 있음을 보여주었다.

• Korean Chemical Engineering Research
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• 제49권5호
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• pp.639-643
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• 2011

저등급석탄의 고품위화 기술 중 하나인 유중 슬러리 건조 공정은 슬러리 혼합, 슬러리 탈수, 유분 회수, 건조, 성형공정으로 구성된 건조 및 안정화 공정이다. 연간 백만 톤 규모의 저등급석탄 고품위화 공정에 대한 경제성을 분석하기 위하여 재료비, 노무비, 경비, 판매관리비를 산정하고 이에 따른 현금흐름을 계산하였다. 투자비 $1억, 할인율 12%, 내용 연수 20년에 대한 IRR, B/C ratio, NPV, 할인투자회수기간을 통해 사업의 경제성을 분석한 결과 모든 투자 기준을 만족하는 것으로 나타났다. 민감도 분석을 통해 투자가치가 원료탄과 제품 가격에 매우 민감한 것을 확인하였으며, 석탄가격이 급등하는 현 추세에서는 예상 투자가치가 증가할 것으로 판단되었다.

• 대한안전경영과학회지
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• 제9권1호
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• pp.197-211
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• 2007

The power of semiconductor, Korea is continuously constructing semiconductor production line for keeping a front-runner status. however, studies and data about potential risks in semiconductor factory are still short. If fire does not initially suppressed, the fire causes a great damage. To decrease fire risk factors, in addition to fire fighting safety equipment, more important thing is how to design and construct fire protection system. The current fire protection codes about semiconductor factory come under functional law, and this law is short of consideration about particularity of factory. The existing prescriptive fire codes depending on experience compose without evident engineering verifications, thus equipments which is created by the current prescriptive fire code may bring about a variety of problems. For example, the design under the current regulation can not cope with the excessive investments, low efficiencies, and the diversifying construction designs and be applied to the quick changes of new technologies. Ergo, an optimal design for fire protection is to equip fire protection arrangements with condition and environment of production field. Manufacturing factory of semiconductors is a windowless airtight space. And for cleanliness, there exists strong flow of cooperation. Therefore, there is a need for fire safety design that meets the characteristic of a clean room. Accordingly, we are to derive smoke flow according to cooperation process within a clean room and construction plan of an optimal sensor system. In this study, in order to confirm the performance of proposed smoke-exhaust equipment and suggest efficient smoke exhaust device when there is a fire of 1MW of methane in the clean room of company H, we have implemented fire simulation using fluid dynamics computation.

• 한국수소및신에너지학회논문집
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• 제24권4호
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• pp.282-287
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• 2013

Hydrogen production from water using solar energy is attractive way to obtain clean energy resource. Among the various solar-to-hydrogen production techniques, a combination of a photovoltaic and an electrolytic cell is one of the most promising techniques in term of stability and efficiency. In this study, we show successful fabrication of precursor solution processed CIGS thin film solar cells which can generate high voltage. In addition, CIGS thin film solar cell modules producing over 2V of open circuit voltage were fabricated by connecting three single cells in series, which are applicable to water electrolysis. The operating current and voltage during water electrolysis was measured to be 4.23mA and 1.59V, respectively, and solar to hydrogen efficiency was estimated to be 3.9%.

• 한국입자에어로졸학회지
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• 제5권4호
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• pp.171-178
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• 2009

$PM_{2.5}$ is one of critical air pollutants due to its high absorbability of heavy metallic fumes, PAH and bacillary micro organisms. Such a fine particulate matter is often formed through various nucleation processes including condensation. This study attempts to find the nucleation behaviors of $PM_{2.5}$ arisen from coal power stations using a classical heterogeneous Fletcher's theory. The numerical simulation by C-language could approximate the nucleation process of $PM_{2.5}$ from water vapor, of which approach revealed the required energy for embryo formation and embryo size and nucleation rate. As a result of the calculation, it was found that wetting agents could affect the particle nucleation in vapor condensation. In particular, critical contact angle relates closely with the vapor saturation. Particle condensation could be reduced by lowering the angles. The wetting agents aid to decrease the contact angle and surface tensions, thereby may contribute to save the formation energy.

• 전기화학회지
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• 제6권1호
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• pp.13-17
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• 2003

직접 메탄을 연료전지의 음극 촉매로 사용되는 Pt-Ru/C를 솔-젤법을 이용하여 크라이오젤 및 에어로젤 형태로 제조하였다. 탄소의 원료가 되는 유기물의 종류에 따라 B종의 촉매를 제조하였으며 XRD분석에 의해 금속이 탄소담체 위에 고분산되어 있음을 확인하였다. 초임계건조, 탄화. 환원 공정을 거쳐 완성된 에어로젤 촉매의 전극 활성은 Cyclic voltametry를 이용한 half cell test를 통하여 평가하였다. 그 중 Phloroglucinol-Formaldehyde(PF) 형의 촉매가 가장 우수한 활성을 보였으며 내구성 또한 양호하였다.