• 제목/요약/키워드: Waste quality

검색결과 1,127건 처리시간 0.025초

파쇄횟수가 순환골재의 품질특성에 미치는 영향 (The Material Properties on the Crushing Effect of Recycled Aggregates)

  • 원철;박상준
    • 한국건설순환자원학회논문집
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    • 제5권1호
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    • pp.125-130
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    • 2010
  • 최근 천연골재의 부족현상과 더불어 도심지의 재개발 재건축 사업 등이 진행됨에 따라 발생하는 막대한량의 폐콘크리트는 현재 당면하고 있는 심각한 문제라 할 수 있다. 따라서 본 연구에서는 원콘크리트의 배합조건 및 골재특성이 콘크리트의 유동 및 강도특성에 미치는 영향을 평가할 목적으로 동일 배합조건의 공시체를 제작하여 6개월간 폭로시킨 후, 파쇄하여 순환 골재로 사용함으로서 원콘크리트에 적용된 콘크리트의 특성이 순환골재의 기초특성에 미치는 영향을 평가하고, 아울러 천연골재와의 혼합비율에 따른 품질개선 효과 등에 대하여 검토하였다. 검토결과, 순환골재를 단독으로 사용하는 방안보다는 양질의 천연골재와 함께 적정비율 혼합하고, 여기에 물-결합재비가 다소 큰 일반강도 범위의 콘크리트에 대상으로 활용하는 것이 유효하다는 결론을 얻었다.

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인천해안의 수질관리를 위한 오염부하량 할당에 관한 연구 (A Waste Load Allocation Study for Water Quality Management of the Incheon Coastal Environment)

  • 김소연;최정현;나은혜;박석순
    • 대한환경공학회지
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    • 제27권1호
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    • pp.43-51
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    • 2005
  • 본 논문은 인천 해안에서 AQUASEA 모델을 적용한 오염부하량 할당 연구를 제시한다. 인천 해안의 복잡한 지형을 표현하기 위하여 유한요소격자망을 구성하였으며, 인천 해안 경계 지역의 13개 지점의 조위와 한강 유량이 조석조위 시뮬레이션을 위한 입력 조건으로 주어졌다. 또한, 해안으로 유입되는 모든 오염원의 부하량이 수질 시뮬레이션 입력 조건으로 주어졌다. 시뮬레이션된 변수는 조류와 화학적 산소요구량이며, 실측값을 이용하여 보정 및 검증되었다. 모델 결과는 대부분의 측정 지점에서 실측값과 적절한 일치를 이루었다. 시스템 분석 결과 한강에서 유입되는 오염물질은 염화수로에서부터 영흥도 북쪽 해역까지 수질에 영향을 미치며, 인천시에서 배출되는 오염물질은 영종도 아래에서부터 자월도 위쪽 해역까지 수질에 영향을 미치는 것으로 나타났다. 또한 시화호에서 방류되는 물은 배출 수문에서부터 인천항까지의 수질에 영향을 보이며, 경기도 연안에서 배출되는 오염물질은 오이도 부근 해역의 수질에 영향을 미치는 것으로 나타났다. 타당성이 검증된 모델의 오염부하량 분석을 통하여 효과적인 수질관리대책을 수립하였으며, 여기서 인천 해안의 수질기준치를 유지하면서 허용될 수 있는 오염부하량을 제시하였다.

폐타이어/폐유의 복합 열분해에 의한 오일화 공정개발 연구 (Oil Recovery through Wasts Tire/Wasts Oil Pyrolysis)

  • 김동찬;신대현;정수현
    • 자원리싸이클링
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    • 제4권4호
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    • pp.12-15
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    • 1995
  • In this paper, some representative waste tire pyrolysis were investigated together with the analysis of the problems associated with the commercialization of various waste tire treatment technologies. Also, R & D results on recovering the oil from the pyrolysis of waste tires, when waste oil was used as a heating medium, were summarized in this study. Experimental results show that the present pyrolysis process has both lower pyrolytic temperature and higher pyrolysis rate than usual one and that the quality of the product oil and residue obtained was relatively even with large availability.

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생태도시 조성을 위한 통합폐기물 관리방안 - 전과정평가(LCA) 기법의 응용 - (Integrated Solid Waste Management in Ecopolis -Applying LCA-)

  • 김익수
    • 환경영향평가
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    • 제8권1호
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    • pp.17-27
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    • 1999
  • Applicability of LCA in establishing the integrated solid waste management were examined. Data were collected from current waste management system. LCA method was then applied to find environmentally sustainable waste management. The process comprises five steps : (1) collecting data, comparing the data with comprehensive urban planning as well, (2) analyzing the current waste treatment procedure leading to the database establishment, (3) LCA for the waste management system, (4) finding alternative scenarios based on the former steps, (5) establishing the optimum method in Ecopolis, best fitted to the local situation. The results and suggestions in this study are expected to yield comprehensive analysis as to current practices in waste management. More importantly it will be a valuable data in minimizing environmental burdens in connecting with living environments of Ecopolis. Information regarding the urban system and total environmental quality are expected from this study.

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잔골재로 폐주물사를 이용한 모르타르의 특성에 관한 실험적 연구 (An Experimental Study on the Mortar Using Waste Foundry Sand as Fine Aggregate)

  • 박보열;정재호;류현기
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
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    • pp.71-75
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    • 2006
  • Problem of the environmental pollution and pollution by vast quantity occurrence of industrial waste by progress of industry is risen recently. Is real condition that waste foundry sand to be industrial waste that happen in casting industry of them has much the occurrence amount and the processing method is depending on most simplicity reclamation and so on. Therefore, by using waste foundry sand in the world by fine aggregate for mortar in recycling side of industrial waste necessity of development for new principal parts aggregate is risen along with rise of aggregate price by exhaustion phenomenon of natrual resources, wish to analyze physical and mechanical properties special quality and foretell practical use possibility availability.

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영농폐비닐 수거율 결정요인 분석 (An Analysis of the Determinants of the Collection Rate of Agricultural Plastic Waste)

  • 이우엘;안동환
    • 농촌계획
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    • 제25권3호
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    • pp.11-18
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    • 2019
  • It is widely known that agricultural plastic waste incineration by farmers may cause big forest fire or fine dust in rural areas. Hence, how to increase the rate of collection and recycling of the agricultural plastic waste is of concern to policy makers especially for rural environment. The purpose of this study is to find the determinants of the collection rate of agricultural plastic waste. This study used the data from 'Research on Agricultural Waste' by the Korea Environment Corporation from year 2012 to 2015 for 163 regions. This study found that the compensation rate for collection, the frequency of collecting services, and the quality of waste are important to increase the collection rate. And the regions with more elderly and low income people are more likely to have higher collection rate. Finally, the chief producing regions that are specialized in a certain crop shows higher collection rate.

당뇨식 잔반 감량을 위한 영양서비스 개선 활동의 효과 (Effects of Nutrition Service Improvement Activities for Reducing Plate Waste of the Diabetic Mellitus Diet in a General Hospital)

  • 손정민;염혜선
    • 대한지역사회영양학회지
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    • 제13권5호
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    • pp.674-681
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    • 2008
  • Hospital malnutrition could be caused by not completing the food served in the hospital. This has been a big problem since it delays the recovery of the patient and extends the length of hospital stay. The purpose of the study was to reduce the plate waste for the DM diet by performing several nutrition service improvement activities. The study was performed in a general hospital with 900 beds. A questionnaire survey was taken by 39 DM patients to obtain their aspect of the hospital foodservice systems and the quality of the meals at the beginning of the study. The amounts of foods served in the hospital kitchen and returned were measured by weights. After the improvement activities, the measurement of the plate waste was performed again for comparison. The average percentage of plate waste for the DM diet was 23.2%. The survey showed no difference by sex, age or duration of admission in plate waste. However, this food wastage percentage showed differences between the patients having a chance to get information about the diet therapy (12.21%) and not having one (26.06%) (p < 0.05). Using a five-point Likert-type scale, the quality of food by its taste was 2.49 (1: very poor, 5: excellent), the temperature score was 3.56 (1: very poor, 5: excellent), and the amount of food served score was 2.95 (1: very poor, 5: excellent), and the preference score was 3.13 (1: very dislike, 5: very like). Nutritional care improving activities were performed by adjusting seasonings, developing new menus, and standardizing cooking methods in order to increase the satisfaction of meal quality. The dietitian's inpatients care protocol was adjusted to expand the nutritional counseling chance for the DM patients. After the improvement activities, the average plate waste was reduced to 14.6%, and the satisfaction of food taste and preference increased to 3.21 (p < 0.001), and 3.36 (p < 0.05) correspondingly. The result shows that, for therapeutic diet patients, food intake could be increased by improving the food service satisfaction by controlling the meal quality and clinical nutritional service activities.

혼파초지에서 메탄발효폐액의 시용이 식생구성 , 수량 및 목초품질에 미치는 영향 (The Effects of Liquid Waste from Methane Fermentation on Botanical Composition , Dry Matter Production and Nutrient Quality of Pasture Mixtures)

  • 김정갑;신재성;임동규
    • 한국초지조사료학회지
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    • 제7권2호
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    • pp.103-108
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    • 1987
  • The experiment was carried out to determine the optimum application rate of liquid waste from methane fermentation (LW) and its effect on botanical composition, dry matter yields and nutrient quality of pasture mixtures. Experimental fields was designed as a randomized block treated with NPK chemical fertilizer (NPK = 28-20-24 kg/lOa), NPK + Water 28 ton, 112 NPK + LW 28 ton, 112 NPK + LW 42 ton, LW 28 ton, LW 42 ton and LW 56 ton/lOa at Livestock Experiment Station in Suweon, 1985. The results obtained are summarized as follows: 1. Vegetation of introduced pastures, both in grasses and legumes, was markedly increased in the plots treated with methane-liquid waste. However, heavy application of liquid waste tended to increase of native weeds such as Polygronum spp., Rumex spp. and Lactuca spp. 2. Crude protein contents was increased in the plants applied with liquid waste, but NFE was decreased compared with those of chemical fertilizer applied. The concentrations of crude fat and crude fibre were, however less affected by the fertilizer resource. Among cell-wall constituents, cellulose content was decreased as the liquid waste application rate increased, while hemicellulose showed a negative association. 3. Productivity of the pasture was increased as the liquid waste application rate increased. The highest dry matter yields was obtained in the plot treated with LW 42 ton/lOa by 71 1 kg/lOa, which shows about 71% increments compared with those of chemical fertilizer treated. Net energy yields, both in starch value and NEL, were also markedly increased under liquid waste application. As a results, the optimum application rate of methane-liquid waste was found to be 42 ton in 10 a.

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반도체 산업폐수의 재이용 기술에 관한 연구 (A Study on the Waste Water Recycling Technology for Semiconductor Industry)

  • 지은상;김재우;신대윤
    • 환경위생공학
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    • 제14권4호
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    • pp.137-142
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    • 1999
  • Current semiconductor industry factories are relying on the end-of-pipe treatment technology for waste water treatment and thus they mostly suffer from severe industrial water shortage. As a result in order to solve those waste and industrial water problems, there requires to be changed to the Clean Technology, that is Pollution Prevention Technology. Through above strategic actions with the Clean Technology, we shall strength more powerful and logical environmental pollution prevention system than those in the past. By changing the end-of-pipe treatment technology for waste water treatment and thus they mostly suffer from severe industrial water problems, there requires to be changed to the Clean Technology, that is Pollution Prevention Technology. Through above strategic actions with the Clean Technology, we shall strength more powerful and logical environmental pollution prevention system than those in the past. By changing the end-of-pipe treatment technology with physical, chemical and biological treatment methods as a mixed stream basis for treating of semiconductor waste stream into clean technology with pollution prevention technology as a waste segregation basis, we can bet 20 to 30% investment reduction as compared with end-of-pipe treatment technology.The results for water quality analysis were as follows : 1. Water quality analysis of the before treatment : pH : 9~10.5, Conductivity : $300~7,000{\mu}s/cm$, TDS : more then $3,000mg/{\ell}$, COD : $200~250mg/{\ell}$, SS : $500~600mg/{\ell}$, n-H : $8.3mg/{\ell}$ 2. Water quality analysis of the after treatment : pH : 6.5~7.5, Conductivity : 0.059, TDS : $40{\mu}s/cm$, COD : $20mg/{\ell}$, SS : $5mg/{\ell}$ n-H : $0.6mg/{\ell}$

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직원 급식서비스의 질 향상 사례 연구 -잔반 줄이기 중심으로- (A Case Study on Quality Improvement of the Food Services for Staff -Focused on Food Waste Reducing-)

  • 이승림;장유경
    • 대한영양사협회학술지
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    • 제10권1호
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    • pp.25-33
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    • 2004
  • The objective of this study is to analyze the effects of the food waste reducing campaign on food service. For this purpose, the author analyzed the quantity of food waste before and after the Quality Improvement(QI) activity and investigated employees' satisfaction with food service. Statistical data analyses were completed using the SPSS 11.0 program. The results can be summarized as follows : The number of employees who used the food service was 374.29$\pm$25.120 before QI and 332.89$\pm$27.274 after QI, so it decreased significantly after QI. The daily quantity of waste food was 39.52$\pm$3.060kg before QI and 19.58$\pm$4.825kg after QI, so it decreased significantly after QI. The quantity of waste food per person was 105.84$\pm$8.907g before QI and 59.07$\pm$15.125g after QI, so it decreased significantly after QI. Among 7 items related to employees' satisfaction, the taste of food was 3.30$\pm$0.890 before QI and 3.51$\pm$0.665 after QI, so it improved significantly after QI. No significant difference was found in the variety of menus, saltiness, temperature and compatibility of side dishes and tableware hygiene but employees appeared to be more satisfied with these items after QI. Employees' satisfaction with kindness/appearance did not show a significant difference but employees appeared to be less satisfied with it after QI.

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