• Journal of Electrochemical Science and Technology
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• 제12권1호
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• pp.21-32
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• 2021

This study reports for the first time the application of electrocoagulation (EC) from laboratory to pilot scales for the treatment of printing wastewater, a hazardous waste whose treatment and disposal are strictly regulated. The wastewater was taken from three real printing companies with strongly varying characteristics. The treatment process was performed in the laboratory for operational optimization and then applied in the pilot scale. The weight loss of the electrode and the generation of sludge at both scales were compared. The results show that the raw wastewater should be diluted before EC treatment if its COD is higher than about 10,000 mg/L. Pilot scale removal efficiencies of COD and color were slightly lower compared to those obtained from the laboratory scale. At pilot scale, the effluent CODs removal efficiency was 81.9 - 88.9% (final concentration of 448 - 992 mg/L) and color removal efficiency was 95.8 - 98.6% (final level of 89 - 202 Pt-Co) which proved the feasibility of EC treatment as an effective pre-treatment method for printing wastewater as well as other high colored and hard-biodegradable wastewaters.

• 한국수산과학회지
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• 제27권6호
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• pp.839-846
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• 1994

Changing concepts in fishery science increasingly are recognizing depletion of traditional stocks, utilization of alternate(non-traditional) species, demand for high quality products, and a total resource utilization approach. Innovative practices are occurring in fisheries processing wherein solid and liquid discharges are no longer treated as 'waste,' but rather as valuable feedstocks for recovery of a variety of value-added ('value enhanced') by-products. Among these are protein hydrolysates, soluble proteins and amino acids, proteolytic enzymes, flavor and flavor extracts, pigments, and biopolymers such as chitosan. Properties and applications of this deacetylated derivative of chitin are noted. Crustacean processing by-products are discussed in terms of their serving as materials for generation of natural flavors and flavor extracts, and products such as fish sauces using contemporary enzymatic techniques. Various food and feed applications of fisheries processing by-products are illustrated with increased usage seen in formulated diets for an expanding aquaculture market. Examples are given of aquaculture becoming increasingly significant in global fisheries resource projections. Critical issues in the international seafood industry Include those of seafood quality, processing quality assurance (HACCP), and recognition of the nutritional and health-related properties of fisheries products. A variety of current seafood processing research is discussed, including that of alternate fish species for surimi manufacture and formulation of value-added seafood products from crawfish and blue crab processing operations. Increasing emphasis is being placed on international aspects of global fisheries and the role of aquaculture in such considerations. Coupled with the need for the aquatic food industry to develop innovative seafood products for the 21st century is that of total resource utilization. Contemporary approaches in seafood processing recognize the need to discard the traditional concept of processing 'waste' and adapt a more realistic, and economically sound, approach of usable by-products for food and feed application. For example, in a period of declining natural fishery resources it is no longer feasible to discard fish frames following fillet removal when a significant amount of residual valuable flesh is present that can be readily recovered and properly utilized in a variety of mince-based formulated seafood products.

• 유기물자원화
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• 제24권2호
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• pp.59-66
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• 2016

본 연구는 음폐수를 대상으로 산발효와 메탄발효가 일체형으로 구성된 혐기성소화방식에 대한 경제적, 기술적 타당성 검토를 위함이며, 이를 위해 현재 운영 중인 24톤/일의 시설 운영현황 분석을 실시하였다. 실험 결과, 음폐수 내에 VS 기준 유기물 제거율은 73.7%로 분석되었으며, 바이오가스는 평균 $1,239m^3$/일($54.4m^3$/톤-투입음폐수)이 생산되었다. 일체형 소화조는 구조 특성상 분리형 2상 소화조 대비 설치 면적과 소요 열량이 각각 15.9%~47%, 11.6%~17.8%의 절감 효과가 있는 것으로 나타났다. 이상의 운전결과를 종합해보면, 분리형 소화 방식 대비 소요부지면적 축소, 시설비 절감 등의 이점이 기대되는 일체형 2상 혐기성소화 방식은 보다 상용화된 대형 플랜트로의 적용 타당성이 높을 것으로 판단된다.

• 농업과학연구
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• 제50권4호
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• pp.697-711
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• 2023

The global waste crisis has been escalating and its consequent impact on soil, water, air pollution, and eventually climate change acceleration has shed light on the importance of reducing waste. Amidst COVID-19 and the following surge in single-use plastics for food delivery, waste generation is on the incline. Companies and governments have embarked on developing various eco-friendly packaging technologies, but their effectiveness on the consumers is vague as definitions of eco-friendly packaging are vague, and research on its link to purchase intention remains scarce. Thus, the adoption of eco-friendly packaging has been slow. To address this issue, this study analyzes the awareness and purchase intention of four visual attributes of eco-friendly packaging-material, verbal statement, eco-label, and color-along with the environmental consciousness among undergraduate university students in Korea through online surveys and the ordered logit regression model. The study distinguished the attributes into evidence-based and conjectural categories. The findings revealed that eco-friendly visual attributes had a positive effect on purchase intention amongst undergraduate students in Korea; however the level of environmental consciousness had marginal effect on the purchase intention of eco-friendly visual attributes. The level of effectiveness also varied with each visual element. Analyses revealed that visual attributes to eco-friendly material had marginal effect on purchase intention; color was deemed not an "Eco-friendly attribute" by most students, and although eco-friendly labels were deemed as an eco-friendly attribute, trust in the labels varied according to environmental consciousness. These findings have implications for businesses and policymakers aiming to promote eco-friendly consumption within packaged food products.

• 유기물자원화
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• 제16권3호
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• pp.52-64
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• 2008

하수슬러지와 음식물 침출수슬러지 또는 제지슬러지를 혼합하여 부숙시킨 후 줄지렁이에게 급이하면서 지렁이의 섭식률 및 생장률을 조사하였다. 하수슬러지에 음식물쓰레기 침출수슬러지를 혼합하여 30일 부숙시킨 것에 대한 지렁이 개체군의 섭식량은 10, 20일 부숙시킨 것에 대한 섭식량보다 높았다. 그러나 부숙기간에 상관없이 먹이 급이 90일 경과 후 지렁이 개체군의 밀도는 감소하였고, 먹이급이 180일 경과 후 지렁이 개체군의 연령구성에서 성충의 비율이 현저하게 높은 것으로 보아 하수슬러지에 음식물쓰레기 침출수슬러지를 혼합하여 부숙시켜 전처리된 먹이는 지렁이 개체군의 차세대로의 성장을 저해하는 것으로 나타났다. 하수슬러지에 제지슬러지를 혼합하여 20일 부숙시킨 것에 대한 지렁이 개체군의 섭식량 및 밀도는 10, 30일 부숙시킨 것보다 높게 나타났다. 부숙기간에 상관없이 먹이급이 90일까지는 지렁이 개체군의 밀도가 증가하였으나, 먹이급이 90일 이후부터 감소하였다. 따라서 하수슬러지를 장기간 급이시 발생하는 밀도 감소에 기인하는 하수슬러지 내 독성물질의 규명 및 이를 제거하는 다른 전처리과정이 필요한 것으로 생각된다. 한편, 줄지렁이 개체군의 밀도, 유충 및 성충의 비율, 섭식량 등을 고려하였을 때, 하수슬러지와 제지슬러지를 혼합하여 20일 부숙시킨 것이 다른 전처리 먹이보다 지렁이퇴비화 가능성이 높은 것으로 판단된다.

• 환경영향평가
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• 제17권5호
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• pp.321-330
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• 2008

Methane is a potent greenhouse gas and methane emissions from landfills have been linked to global warming. In this study, LandGEM (Landfill Gas Emission Model) was applied to predict landfill gas quantity over time, and then this result was compared with the data surveyed on the site, Cheongju Megalo Landfill. LandGEM allows the input of site-specific values for methane generation rate (k) and potential methane generation capacity $L_o$, but in this study, k value of 0.05/yr and $L_o$ value of $170m^3/Mg$ were considered to be most appropriate for reflecting non-arid temperate region conventional landfilling, Cheongju Megalo Landfill. High discrepancies between the surveyed data and the predicted data about landfill gas seems to be derived from insufficient compaction of daily soil-cover, inefficient recovery of landfill gas and banning of direct landfilling of food garbage waste in 2005. This study can be used for dissemination of information and increasing awareness about the benefits of recovering and utilizing LFG (landfill gas) and mitigating greenhouse gas emissions.

• 한국식품영양과학회지
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• 제11권2호
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• pp.31-35
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• 1982

폐액으로 방류되는 두부 폐수(whey)를 이용하여 alcohol 발효를 실시하였으며 다음과 같은 결과를 얻었다. whey중(中)에 함유(含有)된 환원당은 약 0.71%로서 이당(糖)을 이용(利用)하며 l당(當) 최대(最大) 1.86 g의 ethanol이 생산(生産)되었으나 수률(收率)이 낮아서 경제성은 희박하다. 그러나 발효에 의해서 단백질과 당이 각각 94%, 81%만큼이나 감소한 결과(結果)로 미루어 보아 두부 폐수중(廢水中)의 유기물(有機物)을 alcohol 발효(醱酵)에 이용(利用)할 수 있음을 확인(確認)하였다.

• 유기물자원화
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• 제9권2호
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• pp.77-86
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• 2001

As construction and expansion of wastewater treatment works is continuing, generation of sludge is increasing. Bur most sludge is not used appropriately but disposed by landfill dumping to sea. Furthermore direct landfilling of sludge cake containing moisture content over 75% has been legally prohibited since 2001 that's enforcement will be more strict in 2003. Such a situation means nowadays recycling of organic waste such as sludge and food waste is necessary. Composting is one of recycling methods commonly and used as an effective means of stabilizing organic waste and then compost can be used as fertilizer. However fertilizer law management which include standard of compost products and other fertilizers applied all sludge products indiscriminiately and was not flexible. So MOE has graded organic composts according to land applications to improve recycle of organic wastes. The classified organic compost which contains low contaminants has been possible to use as various purpose. This study enalyzed 30 samples which were raw materials for compost and compost products management well and to estimate the quality of compost products. Heavy metals were measured in Raw materials and OM/N, NaCl and VS were tested in compost products as well as heavy metals. As a result, approximate 10% of raw materials was not suitable to the grade A and 6.7% over the grade B of the regulation on raw materials for compost. In the case of 30 produced compost propducts approximate, 57% of composts was not compatible with the grade A and B of the regulation on composting product. The qualities of compost products were worse than raw materials, because the compost products have more regulation item raw materials have.

• Journal of Biosystems Engineering
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• 제43권1호
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• pp.59-71
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• 2018

Purpose: Cellulose nanocrystals (CNCs) are natural polymers that have been promoted as a next generation of new, sustainable materials. CNCs are invaluable as reinforcing materials for composites because they can impart improved mechanical, chemical, and thermal properties and they are biodegradable. The purpose of this review is to provide researchers with information that can assist in the application of CNCs extracted from waste agricultural byproducts (e.g. rice husks, corncobs, pineapple leaves). Methods & Results: This paper presents the unique characteristics of CNCs based on agricultural byproducts, and lists processing methods for manufacturing CNCs from agricultural byproducts. Various mechanical treatments (microfluidization and homogenization) and chemical treatments (alkali treatment, bleaching and hydrolysis) can be performed in order to generate nanocellulose. CNC-based composite properties and various applications are also discussed. Conclusions: CNC-based composites from agricultural byproducts can be combined to meet end-use applications such as sensors, batteries, films, food packaging, and 3D printing by utilizing their properties. The review discusses applications in food engineering, biological engineering, and cellulose-based hydrogels.

• 신재생에너지
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• 제6권2호
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• pp.27-32
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• 2010

Low Calorific Gas Turbine (LCGT) has been developed as a next generation power system using landfill gas (LFG) and biogas made from various organic wastes, food Waste, waste water and Livestock biogas. Low calorific fuel purification by pretreatment system and carbon dioxide fixation by green house system are very important design target for the optimum applications of LCGT. Main troubles of Low Calorific Gas Turbine system was derived from the impurities such as hydro sulfide, siloxane, water contained in biogas. Even if the quality of the bio fuel is not better than natural gas, LCGT may take low quality gas fuel and environmental friendly power system. The mechanical characterisitics of LCGT system is a high energy efficiency (>70%), wide range of output power (30 kW - 30 MW class) and very clean emission from power system (low NOx). A green house has been designed for four different carbon dioxide concentration from ambient air to 2000 ppm by utilizing the exhaust gas and hot water from LCGT system. LCGT is expected to contribute achieving the target of Renewable Portfolio Standards (RPS).