• Title/Summary/Keyword: Materials recycling

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A Basic Study on the Treatment and Recycling of Disused Electric Motor Unit (EMU) (효율적인 폐전동차 처리 및 재활용을 위한 기초 연구)

  • Park, Sung-Hwan;Lee, Jae-Young;Kim, Yong-Ki
    • Proceedings of the KSR Conference
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    • 2007.05a
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    • pp.1250-1252
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    • 2007
  • Recently, a large amount of waste has been occurred from electric motor units (EMUs) due to the excess of their duration or the exchange of interior. In Korea, most of waste has been treated by incineration or landfill because the special treatment system of disused EMUs has not been existed until now. The objective of this study is to investigate the international railroad cases for the efficient treatment of disused EMUs. Japanese railroad makes an effort to enhance the recycling efficiency of rolling stocks such as the use of recycling materials or the development of recycling technology. Also, Europe has decided to treat the disused rolling stocks considering the inspection of their conditions and the increase of management cost. Therefore, in the future, it will be necessary to improve the domestic regulations related to the duration of rolling stocks and to develop the recycling technology of interior preferentially.

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Methods of Separating Used Plastics for Recycling (폐플라스틱의 선별기술)

  • 윤여환
    • Resources Recycling
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    • v.6 no.2
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    • pp.12-21
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    • 1997
  • Plastics waste constitutes approximately 23% by volume of the municipal solid waste(MSW) generated in the U.S. each year, and have slow rate of degradation in the environment. Therefore, there is a great deal of public pressure to recycle plastics, and more than 100 million people participate in the curbside recycling programs. Despite the high level of public interest, only 3.5% of the plastic are recycled, which is substantially lower than the recycle rates of other materials such as paper fibers, glass, and iron. Although a large part of the reason is due to the low price of virgin polymers, which in turn is due to the low price of oil, it is possible to make the plastics recycling as a profitable business by developing advanced technologies. In this communication, various methods of separating pplastics from metals and from each other are discussed.

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Current Recycling Status of End-of-Life Vehicles(ELV) and Proposal of Recycling System Model (자동차(自動車)리싸이클링의 현황(現況)과 리싸이클링모델의 제시(提示))

  • Oh, Jae-Hyun;Kang, Jung-Ho
    • Resources Recycling
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    • v.16 no.1 s.75
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    • pp.15-27
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    • 2007
  • The Korean Auto industry has developed remarkably over the past 30 years. In 2005 alone, Korea produced 3.7 million vehicles, and the number of vehicles registered surpassed the 15 million marks. The rapid growth in registration, however, has given increasing problems to the traffic congestion and the environmental pollution. The system for handling of ELV in Korea is governed by the 'Motor management law'. The law places the responsibility for vehicle scrapping directly on the vehicle owners. The take-back rate of ELV reaches nearly 100% in Korea since 1987. To further entourage recycling, the government introduced the extended producer responsibility system(EPRS) starting January 1, 2003, which imposes waste recycling obligations on producers or importers. According to the system, producers must recycle home appliances and packaging materials. This system, however, did not involve the automobiles. In 2006, the automobiles recycling law is under preparing now by the government. This article is concerning current status for End-of-Life vehicle's recycling and the recycling system model for advanced ELV industries in Korea.

Dialysis in double-pass cross-flow rectangular membrane modules with external recycle for improved performance

  • Yeh, Ho-Ming
    • Membrane and Water Treatment
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    • v.2 no.2
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    • pp.75-89
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    • 2011
  • The predicting equations for mass transfer rate in cross-flow rectangular dialyzers with double flow and recycle, have been derived by mass balances. The recycling operation has two conflicting effects. One is the desirable effect of the increase in fluid velocity, resulting in an increased mass transfer coefficient. The other is the undesirable effect of the reduction in concentration difference due to remixing, resulting in decreased mass-transfer driving force. In contrast a single-pass device without recycling, considerable improvement in mass transfer is achieved if the cross-flow rectangular dialyzer of same size is operated with double pass and external recycling. It is concluded that recycle can enhance mass transfer, especially for larger reflux ratio.

A Fundamental Study on Supercritical CO2 Curing of Resource-Recycling Concrete Containing Concrete Sludge Waste as Main Materials (레미콘 슬러지 고형분을 주재료로 한 자원순환형 콘크리트의 초임계 CO2 양생에 관한 기초적 연구)

  • Sim, Sang-Rak;Lee, Young-Do;Ryu, Dong-Woo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.27-28
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    • 2022
  • In this study, the mechanical properties of resource-recycling concrete containing concrete sludge waste as main materials was compared depending on whether supercritical CO2 curing was applied for the realization of CCU technology. After supercritical CO2 curing, the compressive strength of the steam-cured specimen was lowered, but it was confirmed that the compressive strength of the underwater-cured specimen was improved.

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A Study on the Change of Optical and Mechanical Properties by Reprocessing for High Melt-Indexed Polycarbonate Used in Injection Molded Optical Parts (광학용 사출성형품에 사용되는 고유동성 폴리카보네이트의 재사용에 따른 광학적, 기계적 물성 변화에 대한 연구)

  • Lee, J.H.;Kang, J.J.;Yoon, K.H.;Kim, J.S.
    • Transactions of Materials Processing
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    • v.27 no.4
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    • pp.211-221
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    • 2018
  • To estimate the recycling feasibility of high melt-indexed polycarbonate, 3.5 inch LGP, tensile, flexural and impact specimens were injection-molded and the LGP was shredded into scraps. The scraps were injection-molded again and this process was repeated for 4 times. Properties of the sample, i.e., optical properties, mechanical properties and number average molecular weight were measured at each cycle. Based on the results, as the number of reprocessing increased, transmittance decreased at low wavelength and color coordinate was changed systematically to yellow. Yellow index increased more than twofold during 4 recycling processes. On the other hand, the number average molecular weight decreased during recycling processes. Flexural and impact strength showed no tendency according to the number of recycling, but tensile strength decreased sharply after the third recycling process. Based on these properties, it was concluded that the number of recycling for high melt-indexed polycarbonate allowed in this study was one.