• 한국해양환경ㆍ에너지학회지
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• 제15권1호
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• pp.47-53
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• 2012

중소형 폐 선박으로부터 생성되는 FRP를 재활용하기 위한 방법으로 층상으로 배열된 로빙층과 매트층을 분리하는 것은 친 환경적이면서도 경제적 재활용의 장점을 가지고 있다. 그러나 효율적으로 로빙층과 매트층을 분리하는 기술과 로빙층은 매트층에 비해 얇은 두께로 존재한다는 이유로 인해 로빙층을 매트층과 분리할 때 기계가 자동적으로 층간의 차이를 인식하는 방법은 아직 개발이 이루지지 않고 있다. 본 연구에서는 유리의 구성비가 다른 두 층의 화학적 성질의 차를 이용하여 광학적으로 층간 인식이 가능한 방법을 모색하였다. FRP에 대해 수지를 녹이는 진한 황산, 또는 유리를 녹이는 염기성 용액(KOH의 메탄올과 아이소프로판올 용액), 유리의 $SiO_2$와 반응하는 플루오르산(HF) 용액 등을 활용하여 두 층간의 차별화가 일어났다. 더 효율적으로는 HF 용액으로 처리한 후 수용성 물감으로 착색시킴으로써 광학적인 분별이 가능하였다. 층간 분별과 자동화된 층분리로 폐 FRP의 분리 공정이 단순화, 자동화를 달성하게 되었다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.48-51
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• 1998

This paper presents the transport and removal of organic substances from the contaminated soft soils and sludges such as marine dredging waste, marine sediments, mine tailing waste, and sewage sludge by electroosmosis. A series of laboratory experiments including variable conditions such as contamination levels, solid contents, and applied voltage rates were peformed with the contaminated soft clay specimen mixed with organic substance. Investigated are specimen density, dewatering rate, outflow rate, and outflow concentration. The test results showed that organic substances in the soils were removed by applied voltages. The results indicated that this process can be used efficiently to clean up the contaminated soil.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 Proceeding of CIN-KIN Joint Symposium 2000 on M.E.T. Under STCW 78/95 and SINO-KOREA MARITIME CONTACT IN MID-CENTURIES
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• pp.83-91
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• 2000

This paper illustrates a new idea methods and results of WPD oil applied to marine diesel engines. in recent years, we must make an effort to develop an advanced technique for recycling of waste plastics in order to utilize scrapped plastics as fuel source for diesel engine. It is very important and necessary for us to cope with the increasing calorific value and the growing need of environment protection. The experiment fuel oil was obtained by mixing of diesel oil, WPD and water.

• Journal of Advanced Marine Engineering and Technology
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• 제28권2호
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• pp.243-251
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• 2004

Absorption chiller/heater can utilize the unused energy of the daily life waste heat, the industry waste heat. the solar energy and the earth energy. These can contribute to energy savings. But the absorption chiller/heater has a demerit that the size of absorption chiller/heater is larger than that of the vapor compression type based on same capacity. In this study. the experimental apparatus of an absorber is manufactured as a plate. which is newly applied in an absorber. The experimental apparatus is composed of a plate type absorber. which can increase the heat exchange area per unit volume and thus facilitating to deeply investigate more detail features instead of that done by the existing type. i.e.. horizontal tube bundle type. The characteristics of heat transfer and refrigeration capacity are studied experimentally. The absorption enhancement by using surfactant is closely examined through the experiment and comparative figures are presented in quantitative and qualitative analysis.

• 한국태양에너지학회 논문집
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• 제36권1호
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• pp.19-26
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• 2016

Biomass has been used for energy sources from the prehistoric age. Biomass are converted into solid, liquid or gaseous fuels and are used for heating, electricity generation or for transportation recently. Solid biofuels such as bio-chips or bio-pellet are used for heating or electricity generation. Liquid biofuels such as biodiesel and bioethanol from sugars or lignocellulosics are well known renewable transportation fuels. biogas produced from organic waste are also used for heating, generation and vehicles. Biomass resources for the production of above mentioned biofuels are classified under following 4 categories, such as forest biomass, agricultural residue biomass, livestock manure and municipal organic wastes. The energy potential of those biomass resources existing in Korea are estimated. The energy potential for dry biomass (forest, agricultural, municipal waste) were estimated from their heating value contained, whereas energy potential of wet biomass (livestock manure, food waste, waste sludge) is calculated from the biological methane potential of them on annual basis. Biomass resources potential of those 4 categories in Korea are estimated to be as follows. Forest biomass 355.602 million TOE, agricultural biomass 4.019 million TOE, livestock manure biomass 1.455 million TOE, and municipal organic waste 1.074 million TOE are available for biofuels production annually.

• 한국환경과학회지
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• 제30권6호
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• pp.429-439
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• 2021

Food waste is both an industrial and residential source of pollution, and there has been a great need for food waste reduction. As a preliminary step in this study, waste reduction is quantitatively modeled. This study presents two models based on kinetics: a simple kinetic model and a mass transport-shrinking model. In the simple kinetic model, the smaller is the reaction rate constant ratio k₁, the lower the rate of conversion from the raw material to intermediate products. Accordingly, the total elapsed reaction time becomes shorter. In the mass transport-shrinking model, the smaller is the microbial decomposition resistance versus the liquid mass transfer resistance, the greater is the reduction rate of the radius of spherical waste particles. Results showed that the computed reduction of waste mass in the second model agreed reasonably with that obtained from a few experimantal trials of biodegradation, in which the microbial effect appeared to dominate. All calculations were performed using MATLAB 2020 on PC.

• 청정기술
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• 제28권1호
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• pp.32-37
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• 2022

Food waste is produced from food factories, food services, and home kitchens. The generated mass reached 5.4 million tons/year in 2020. The basic management technology for such waste has been biological degradation under an anaerobic environment. However, the whole process is intrinsically slow and considerably affected by the inner physicochemical properties of the waste and other surrounding conditions, which makes optimization of the process difficult. The most promising options to counter this massive generation of waste are eco-friendly treatments or recycling. As a preliminary step for these options, attempts were made to evaluate the feasibility and usability of three simulative models based on reaction kinetics. Model (A) predicted relative changes over reaction time for reactant, intermediate, and product. Overall, an increased reaction rate produced less intermediate and more product, thereby leading to a shorter total reaction time. Particle diminishing model (B) predicted reduction of the total waste mass. The smaller particles diminished faster along with the dominant effect of microbial reaction. In Model (C), long-chain cellulose was predicted to transform into reducing sugar. At a standard condition, 48% of cellulose molecules having 10⁵ repeating units turned into reducing sugar after 100 h. Also it was found that the optimal enzyme concentration where the highest amount of remnant sugar was harvested was 1 mg L^-1.

• 대한설비공학회지:설비저널
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• 제15권4호
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• pp.362-371
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• 1986

In the normal Refrigeration process, the condensation heat of refrigerant s not been used because of its low-temperature waste heat. To recover the condensation waste heat of R-12 refrigerator, a drying and hot water system was designed and experimented. The results obtained were summarized as follows: 1. As the temperature a temosphere was increased, the temperature of discharge gas of compressor was increased. And the temperature was $80-84^{\circ}C$ for air condensing type and was $68-71^{\circ}C$ for water condensing type during summer. 2. The condensation waste heat could be obtained up to $50-55^{\circ}C$ of drying heat-source and Hot water in summer. In this case, recovered rate was about $73\%$. And the more temperature of drying Heat-source and Hot water were increased, the more a recovered rate were decreased. 3. When comparing drying characteristics of Agro-products in dryer of waste heat utilization and Hot air, there was no quality difference in products. But drying time of the former was 3 Hours longer than the latter. 4. The condensation waste heat of compressor could be applied into the drying of marine products, the predrying of agro-products and making hot water. And showed high possibility of the waste heat using in low-temperature storage.

• 한국수산과학회지
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• 제34권4호
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• pp.389-393
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• 2001

굴통조림 가공부산물 (세척수 및 자숙수) 유래 혼합분말수프를 효율적으로 이용하기 위해 이의 품질안정성에 대하여 검토하였다. 굴열수추출물 유래 분말 수프는 열수추출물 분말에 식염, 분말크림, 유대체 분말, 밀가루, 옥수수분말, 전분, 포도당, 양파가루의 일정량씩을 각각 혼합하여 제조하였다. 굴통조림 가공부산물 유래 혼합분말 수프는 열수추출물 유래 분말 및 식염대신에 세척액 및 자숙수 유래 혼합 분말 (자숙액 유래 분말 : 세척액 유래 분말=12:8)을 첨가하고, 기타 첨가물의 경우 굴 열수추출물 유래 분말 수프와 같은 비율로 첨가하여 제조하였다. 굴 통조림 가공부산물 유래 혼합분말수프의 경우 저장 중 수분함량, 수분활성, 과산화물값 및 지방산 조성은 거의 변화 없었고, pH, 휘발성염기질소, 갈변도는 약간 증가하는 경향을, 백색도는 약간 감소하는 경향을 나타내었다. 이와 같은 저장 중 성분 변화 경향은 굴통조림 가공부산물 유래 혼합분말수프와 굴 열수추출물 유래 분말수프 간에 차이가 거의 없었다. 이들 굴을 이용한 분말수프를 식용할 수 있게 조리하여 관능검사한 결과 저장 12개월 동안 품질에 큰 변화가 인정되지 않았다. 이상의 이화학적 및 관능적 검사 결과로 미루어 볼 때 굴 통조림 가공부산물 유래 혼합분말수프는 알루미늄 적층 필름(OPP, $20{\mu}m/PE,\;20{\mu}m/paper,\;45g/m^3/PE,\;20{\mu}m/Al,\;7{\mu}\;m/PE,\;20{\mu}m$)에 포장하는 경우 상온에서 12개월 동안 품질변화가 크게 인지되지 않아 안전하게 유통 가능하다고 판단되었다.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.265-266
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• 2001

PCDDS and PCDFs are very stable chcmicals and have very long residence times in the environment and in organisms, including humans. Their hydrophobicity promotes accumulation in sediments and organisms, resulting in high concentrations in both sediments and organisms. Among toxicological effects reports arc teratogenicity, reduce reproduction, liver toxicity, decreased growth rate and behavioral changes (Zeise et al., 1990; Huff, 1992). PCDDs/DFs are inadvertently produced from various combustion sources and manufacturing processes, such as municipal solid waste incineration (Olie et at., 1977), motor vehicles (Marklund et al., 1987), steel mills (Tysklind et al., 1989), and chemical production processes (Hutzinger et al., 1985). (omitted)