• 산업기술연구
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• 제21권B호
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• pp.45-49
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• 2001

Many cities and provinces are rapidly depleting landfill spaces. As the result, some municities have adopted to incinerate their municipal solid waste(MSW). The motive behind the choice is that incineration significantly reduces the volume of solid waste in need of disposal, destroys the harmful organic compounds that are present in MSW, and provides an attractive source of alternative energy. Conclusively, the generation of MSW ash is expected to increse in the furture. However, disposing the MSW ash in landfills may not always be an environmentally or an economically feasible solution. This paper addresses the various issues associated with MSW ash and its possible use in construction applications.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.528-535
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• 2000

Solid waste incinerator is expected to become widely used in Korea. The incineration of solid waste produces large quantities of bottom and fly ash, which has been disposed of primary by landfilling. However, as landfills become undesirable other disposal method are being sought. In this study, an experimental research is conducted to determine the geotechnical properties of municipal solid waste incinerator fly ash(MSWIF) in order to evaluate the feasibility of using the material for geotechnical applications. Basic pysicochemical characteristics, moisture-density relationship, strength, permeability, and leaching characteristics are examined. The results of MSWIF are compared to other MSWIF and coal fly ash which are used as construction material. In addition, the effectiveness of cement stabilization is investigated using various mix ratios. The result of stabilized mixes are compared to the unstabilized material. Cement stabilization is found to be very effective in reducing permeability, increasing strength, and immobilizing heavy metals. This results indicate that MSWIF with cement stabilization may be used effectively for geotechnical application.

• 청정기술
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• 제7권1호
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• pp.27-34
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• 2001

CMP공정에서 발생되는 slurry는 다량의 입자성 물질과 중금속을 함유하고 있다. 이 폐 slurry는 응집성과 침강성에 문제가 있어 처리에 어려움이 있다. 따라서, 본 연구에서는 PACI과 Alum을 이용한 Jar-tester를 통하여 용수 재활용을 위한 최적 응집 조건을 도출하고자 하였다. 고형물 함량이 0.1wt%의 경우 PACI을 응집제로 사용할 때 최적 응집 조건은 pH 4 부터 6에서 투여량은 20~50 mg/L 였으며, 0.5 wt%의 경우 pH 4와 5에서 응집제 투여량은 50~100 mg/L였다.

• Environmental Engineering Research
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• 제20권3호
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• pp.268-276
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• 2015

Solid waste production increases due to population and consumption increments. Landfill is the ultimate destination for all kinds of municipal solid waste; and is the most convenient waste disposal method in developing countries. To minimize investment and operational costs and society's opposition towards locating landfills nearby, proper landfill sizing and siting are essential. In this study, solid waste forecasting using Autoregressive Integrating Moving Average (ARIMA) was integrated with government future plans and waste composition to estimate the required landfill area for the state of Selangor, Malaysia. Landfill siting criteria were then prioritized based on expert's preferences. To minimize ambiguity and the uncertainty of the criteria prioritizing process, the expert's preferences were treated using integrated Median Ranked Sample Set (MRSS) and Analytic Hierarchy Process (AHP) models. The results show that the required landfill area is 342 hectares and the environmental criteria are the most important; with a priority equal to 48%.

• 한국응용과학기술학회지
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• 제27권4호
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• pp.437-444
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• 2010

Dry Process(natural drying, hot-air drying, oil fry drying), optimized mixture ratio and the condition of carbonization was carried out in order to improve the product durability develop eco-friendly solid fuel mixing food waste and paper sludge. As a result of the experiment, oil fry drying process was the fastest method for drying food waste and paper sludge mixture that contains 80% water inside, and the optimized mixture ratio to minimize the generating concentration of chlorine gas against caloric value of mixture ratio was 7:3. Additionally proper temperature of product carbonization was about $200^{\circ}C$ and shown increasing product durability through the carbonization. Therefore, the pelletized solid fuel be shaped diameter around 0.5cm, length 2cm under which was pulverized and molded using 7:3 mixture of food waste, and paper sludge was the eco-friendly solid fuel possible to be industrialized which is consist of chlorine concentration of below 2.0wt% and the lowest caloric value of over 5,000kcal/kg. In conclusion, this developing manufacturing process of the solid fuel can be interpreted to contribute alternative energy development in accordance with low carbon and green growth era.

• Environmental Engineering Research
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• 제22권3호
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• pp.237-244
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• 2017

At present, in India, handling of solid waste has become a major challenge for the municipal authorities. Composting of solid waste, especially organic waste, can be one of the solutions to tackle the issue of handling solid waste. The present study is focused on agitated piles composting of flower waste (FW). Five combinations of FW with dry leaves (DL) and cow dung (CD) were prepared to conduct the study. Significant changes were observed due to the addition of bulking agent. The bulking material helps to reduce the production of leachate and also to maintain the aerobic condition within the piles. The reduction of total organic carbon was 21% in FW composting which increased by 36.48% during the composting of FW on addition of DL and CD. On the 120th day of composting, the pH of pile five (70 kg FW + 20 kg CD + 15 kg DL) was 7.33, electrical conductivity 2.77 mS/cm, total organic carbon 26.9%, total nitrogen 2.2%, and C:N ratio was 12. Appropriate proportion of waste mixture played an important role in providing favorable conditions for the microbial transformation of flower waste to stabilized compost. Finally, FW with the combination of CD and DL was found to be successful during pile composting.

• 신재생에너지
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• 제16권2호
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• pp.47-53
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• 2020

The amount of food waste and its water content depends on both the season and region. In particular, the water content typically varies between 73.8 wt.% and 83.3 wt.%, depending on the proportion of vegetables. Current food waste drying technologies are capable of reducing the water content to less than 10 wt.%, while increasing the heating value. Ongoing studies aim to utilize dried food waste as fuel. Food waste can be used to produce solid refuse fuel (SRF) by mixing it with various solid fuels or other types of waste. The analysis of specimens is very important when considering the direct combustion of food waste or its co-firing with solid fuels. In this study, the weight reduction of specimens after burning them in a small combustor, and compared with the results of thermogravimetric analysis (TGA). The concentration of various chemicals was also measured to define the characteristics of waste generation. Performed proximate analysis, elemental analysis, TGA, combustion experiment, the heating value, and derivative thermogravimetry (DTG).

• 에너지공학
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• 제26권1호
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• pp.76-83
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• 2017

In this paper, the carbon resources recycling of the overview of coffee waste generation in Vietnam. Since few years, there has been a significant research studies was done in the areas of coffee waste generation areas and also waste water generation from coffee production. The coffee residue (solid) and waste water (liquid) both are caused the underground water contamination and also soil contamination. These residues contain high organic matter and acid content leads to the severe threat to environment. In second stage of coffee production process, the major solid residue was generated. Various solid residues such as spent coffee grounds, defective coffee beans and coffee husks) pose several environmental concerns and specific problems associated with each type of residue. Due to the unlimited usage of coffee, the waste generation is high. At the same time, some researchers have been investigated the spent coffee wastes are the valuable sources for various valuable compounds. Biodiesel or biomass productions from coffee waste residues are the best available utilization method for preventing the landfill problems of coffee waste residues.

• 한국환경보건학회지
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• 제31권1호
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• pp.15-22
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• 2005

This study was conducted to evaluate air injection mode on stabilization of solid waste in lysimeter. For three lysimeters, one was maintained under anaerobic condition as control, and air was injected into two lysimeters in continuous mode (atmospheric pressure) and intermittent mode (high pressure of 2 bar). Distilled water was sprayed over solid waste in 1.4 l/$m^3$(solid waste)/day, supposing rainfall intensity of 1,200 mm/yr and 30% infiltration. Oxygen in landfill gas was not detected in control lysimeter during operational days. After 30 day-aeration, oxygen concentrations of continuous and intermittent modes were maintained in 14% and 6%, respectively. $COD_{Cr}$ removal efficiencies of continuous and intermittent modes were about 70% and 50%, and BOD5 removal efficiencies were about 80% and 20%, respectively. In view of oxygen supply, and $COD_{Cr}$ and $BOD_5$ removal, continuous air injection mode of atmospheric pressure was more effective than intermittent mode of 2 bar. Settling degree of solid waste in case of two air injection modes was 3 times higher than that of anaerobic condition as control. Considering the above results, it was thought that air injection (especially continuous atmospheric pressure) could improve degradation of solid waste and induce preliminary stabilization in landfill site.

• 한국미생물·생명공학회지
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• 제41권1호
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• pp.52-59
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• 2013

The nutritional requirements for the maximum production of lipopeptides by Bacillus subtilis N7 (B. subtilis N7) were investigated and optimized using response surface methodology (RSM) under shake flask fermentation. A one-factor-at-a-time experimental setup was used to screen carbon and nitrogen sources. A Plackett-Burman design (PBD) was employed to screen the most critical variables for lipopeptides production amongst ten nutritional elements. The central composite experimental design (CCD) was finally adopted to elucidate the composition of the fermentation medium. Statistical analyses (analysis of variance, ANOVA) of the results showed that KCl, $MnSO_4$ and $FeSO_4{\cdot}6H_2O$ were important components and that their interactions were strong. Lipopeptide production was predicted to reach 709.87 mg/L after a 60 h incubation using an optimum fermentation medium composed of glucose 7.5 g/L, peanut oil 1.25 g/L, $MgSO_4$ 0.37 g/L, $KH_2PO_4$ 0.75 g/L, monosodium glutamate 6.75 g/L, yeast extract and $NH_4Cl$ (5:3 w/w) 10 g/L, KCl 0.16 g/L, $FeSO_4{\cdot}6H_2O$ 0.24 mg/L, $MnSO_4$ 0.76 mg/L, and an initial pH of 7.0. Lipopeptide production ($706.57{\pm}3.70$ mg/L) in the optimized medium confirmed the validity of the predicted model.