• 한국도로학회:학술대회논문집
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• 2002.10a
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• pp.89-92
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• 2002

The objective of this research is to evaluate engineering properties of recycled aggregates, slag as coarse & fine aggregate and waste foundry sand(WFS) as fine aggregate, in hot mix asphalt(HMA). In this research, soundness, gradation and particle analysis, abrasion, specific gravity and absorption test were carried out. The optimum asphalt binder content(OAC) for various HMA combinations of recycled aggregate was determined by Marshall Mix Design. The ranges determined is between 7.2% and 7.5%. Indirect tensile test, resilient modulus test, creep test were carried out for characterization of rutting behavior of various combination of HMA. Judging from the limited tests, the HMA with recycled aggregates is not as good rutting resistance as the HMA with common aggregates. After finishing the Wheel tracking test, the application or feasibility for the use of recycled aggregate as asphalt paving material will be determined.

• Applied Chemistry for Engineering
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• v.25 no.4
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• pp.409-413
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• 2014

This study was carried out to design the optimum mixing ratio of aggregate, cyclic aggregate, and binder (moisture, emulsified asphalt, and emulsion type additives) and produce recycling cold asphalt paving mixture satisfying site work standard. The cyclic aggregate satisfying KS F 2572 was collected from waste asphalt by adequate processing. As the moisture content increased, the shearing strength was decreased. The maximum marshall stability was shown at the 3.0 wt% moisture content. So the optimum moisture content was 3.0 wt%. The marshall stability and flow value with the amount of emulsified asphalt was satisfied in the range of 0.5~2.5 wt%, and the porosity was satisfied in the range of 0.7~2.5 wt%. So the optimum amount of emulsified asphalt was 1.6 wt%. The optimum amount of emulsion type additive was 0.1 wt% in the light of marshall stability and degree of saturation of recycling cold asphalt mixture.

• Resources Recycling
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• v.28 no.4
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• pp.15-22
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• 2019

Coal combustion products are generated during coal combustion and can be grouped into fly ash and bottom ash depending on collection methods. Fly ash and bottom ash can be recycled for various purposes based on their characteristics. Australia is the fourth largest coal production country in the world and reuses coal ash as cement, concrete, mine filler, and agricultural soil amendment. When fly ash is used as a supplement for cement and concrete, strength of the cement and the durability of the concrete can be improved. Use of coal combustion product for mine backfill stabilizes underground mine voids and stores a large amount of coal ash in the voids. Because of alkalinity of coal combustion products, it can neutralize acid mine drainage when used for mine backfill. In addition, it can be used as an agricultural soil amendment to improve acidity and physical properties of the soil and to supply plant nutrients. Recycling of fly ash in Australia will be further expanded because of its low trace element contents that can be toxic to plants and low radioactive element contents existing within soil background concentrations. The characteristics of coal combustion products are related to the characteristics of the coal used for combustion, and since Korea imports coal from Australia, Korean coal combustion products also can be recycled for various purposes.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.144-164
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• 2017

The purpose of this study is to analyze the tourism motivation of Chinese tourists visiting Daming Palace and Terra Cotta Warriors and to study market segmentation according to the motivation. As well as to research the difference of satisfaction toward cultural heritage utilization between Daming Palace and Terra Cotta Warriors. According to the results of the analysis, it was found that cultural heritage tourists preferred cultural experience of tourist sites. Therefore, it is necessary to put effort into cultural experience of cultural heritage sightseeing spots. What's more, it was showed that the preservation and recovery state of cultural heritage, the reality, the value of tangible cultural heritage, the experience programs related to cultural heritage, interpretation service, travel guides, rest facilities, symbolism of souvenirs, admission tickets, nearby restaurants and accommodation facilities could be influence factors of satisfaction toward cultural heritage utilization. The Managers of cultural heritage sightseeing spots are expected to preserve the cultural heritage well and to enhance the facilities and staff professionalism, to make visitors more easily understand cultural heritage, to put more emphasis on interpretation service, to make visitors feel that they got educational effect from visit experience, which will increase the satisfaction of cultural heritages.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.7
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• pp.72-84
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• 2001

This paper proposes a design methodology for customer, assembly and disassembly considering recycling. The disign process starts with the identification of customer needs, which are in turn converted into functional requirements. The concepts of Design for Customer(DFC), Design for Assembly(DFA), Design for Variety(DFV) and Design for Disassembly(DFD) are considered in the product design phases in order to decreas production variety and mass customization. And, a new module generation approach is developed for rearranging and clustering parts and subassemblies for disassembly and recycling. Based on the result of the module generation, a new configuration methodology is suggested to minimize the disassembly time or number of disassembly operations for recycling.

• Resources Recycling
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• v.32 no.3
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• pp.57-67
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• 2023

The treatment of waste plastic has primarily been entrusted to small companies, which has resulted in challenges in obtaining an accurate overview of the current state of affairs and ensuring profitability. Consequently, despite the presence of recycling technology, their practical application has proven to be challenging. In this study, as part of the waste plastic material recycling plan, it is assumed that the PET/OPP laminated waste film is peeled off at the waste film generation site for the second use. The recycling rate of PET/OPP delaminated waste film is assumed to be 2%, 10%, and 30% referring to the figures suggested by "Life-cycle Post Plastic Measures" from the Korean government. In this study, a physical separation method was developed as a recycling approach for waste PET. A result of cost-benefit analysis was conducted to evaluate the economic viability of the recycling process based on changes in the recycling rate. The findings indicated that a recycling rate of waste PET was 30% or higher resulted in a cost-benefit ratio (Benefit-cost ratio, BCR) of 1.32, exceeding the threshold of BCR ≥1, which is considered to meet the minimum requirement for cost-benefit balance. As the government's allocation ratio and unit price are expected to increase in the future, the cost-benefit ratio is expected to increase further. This case is expected to serve as a pilot initiative for waste PET recycling and foster profit creation for businesses in similar industries.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.97-106
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• 2005

현재 우리나라에서만 연간 약 26만들이 발생되고 있는 농업용 폐비닐은 재생원료로 재활용되어지면 국내외에서 그 용도가 매우 많으나 멀칭용으로 사용되었던 폐비닐은 그 오염도가 워낙 심하여 쉽게 재활용할 수 없는 처지이다. 즉 공급과 수요는 많으나 재생기술의 한계가 병목으로 작용하고 있는 현실이다. 따라서 간단하고 경제적인 방법으로 재활용할 수 있는 습식 및 건식 재생기술의 개발이 계속되어 요구되어 왔다. 강제 세척, 회전분리, 열풍 건조 및 압착성형을 이용한 새로운 간이습식공정을 통하여 멀칭용 농업용 폐비닐을 순도 95% 이상의 탄화 및 열화가 적은 압착 펠렛을 경제적으로 제조할 수 있었다. 이들의 재생 수지는 인장강도 $168.6{\pm}3.9kgf/cm^2$, 파단신을 315.8%, 인장탄성을 $2,551.8{\pm}50.1kgf/cm^2$, 굴곡강도와 굴곡탄성을 $166.7{\pm}7.4kgf/cm^2,\;5,716.2{\pm}242.2kgf/cm^2$ 그리고 충격강도는 $49.2kgf\;cm/cm$을 각각 보여 연질수지로써 기능하기 위한 충분한 성능을 보유하고 있음을 알 수 있었다. 또한 이들의 응용분야 확대를 위하여 fly ash 및 탄산칼슘을 배합하여 이들의 물성변화를 살폈다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.115-122
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• 2018

In this paper, the feasibility of recycling concrete waste as a method to reduce final disposal amount of wastes generated through decommissioning of nuclear power plant has been analyzed based on experimental results of existing literature. When recycled concrete waste was used as recycled aggregate, it was investigated through literature that the concrete strength decreased by 30~40% depending on the mixing ratio. It was also investigated that concrete with recycled aggregate can be used as a structural material when the quality of recycled aggregate is well managed since no significant problem was found. When recycled cement produced from concrete waste was used, the strength of concrete or mortar decreased considerably as the recycled cement content increased. Therefore, it can be concluded that concrete or mortar with recycled cement can be used as a filling material for final disposal of large radioactive waste rather than for structural use. This paper is expected to be useful for reduction on disposal volume and decommissioning cost for nuclear power plants such as Kori 1.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.2
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• pp.7-30
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• 1998

Generation and recycling potential of organic waste in Korea were estimated. Status of organic waste composting and compost utilization also were surveyed to promote the recycling of organic waste. From 1994 to 1997, generation of garbage decreased gradually while recycling rate increased due to positive governmental strategy. During the same period, livestock waste increased 11.2%. Municipal wastewater sludge was generated 3,500 ton/day which was 0.03% of wastewater treated in 1996. The energy Potential of industrial organic waste was estimated to 288 million TOE which was 1.75% of the nationwide first energy consumption in 1996. Recycling of industrial sludge was low to 31%, while recycling of animal waste, plant scraps, and wasted paper were relatively high over 50%. Industrial sludge should be recycled more as it was the most part of industrial organic waste. Conventional composting materials were mainly livestock waste, food processing waste, fishery waste, sawdust, and nightsoil. Garbage and sludge have been composted recently. 420,000 tons of compost in 1996 were produced by 288 makers, the most of which were utilized in agriculture. It was suggested that separated collection, compost standard, and quality management should be provided to promote the composting of organic waste.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.279-287
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• 2007

An ore of stone obtained from quarry lose its about 60% such as the muck and the stone-dust during the process of making the architectural block, the crushed aggregate and so on. A part of the muck is only reutilized for the crushed aggregate as road pavement materials, while the most of the muck in the shape of powder is mixed with water and then it is deposited in a sludge tank. The muck in the shape of powder is called the stone-dust. If the stone-dust is discharged and sprayed, an ecosystem will have terrible damage because the seepage of surface water, the flow of ground water and the movement of air are not occurred smoothly by packing the void of soils. As the Waste Management Law (2003) in Korea, the stone-dust is sorted out the industrial waste and the most of that is dumped in ground. Therefore, the establishments of an efficient recycling plan are necessary through the improvement of engineering properties of the stone-dust. To investigate the possibility of recycle and improvement for the stone-dust, the stone-dust and natural soils are sampled from six quarries in Korea. The various soil tests are performed by use of the mixed soils with the stone-dust content ratio. As the result of various soil tests, the recycle possibility of the stone-dust is analyzed as subbase layer materials of the roads.