• Title/Summary/Keyword: e-waste

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Shear Properties of Waste Tire-Bottom Ash Mixture with Different Particle Size of Waste Tire (폐타이어 입경에 따른 폐타이어-저회 혼합토의 전단특성)

  • Kim, Yun-Tae;Kang, Hyo-Sub
    • Journal of the Korean Geotechnical Society
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    • v.26 no.2
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    • pp.55-62
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    • 2010
  • This paper investigates the shear properties of waste tire-bottom ash mixture with various particle size of waste tire powder. Test specimens were prepared at 5 different percentages of waste tire powder content (i.e., 0%, 25%, 50%, 75%, 100% by weight of the dry bottom ash), and with three different particle sizes of waste tire powder (i.e., 0.1 mm~2.0 mm, 0.9 mm~5 mm and 2 mm~10 mm). In this study several series of direct shear tests were carried out. The experimental results indicate that the mechanical characteristics of waste tire-bottom ash mixture are strongly influenced by the particle size as well as waste tire powder content. It is shown that the shear strength and internal friction angle of waste tire-bottom ash mixture decrease with an increase in waste tire powder content. However, the shear strength and internal friction angle of the mixture increase due to interlocking effect between waste tire powder and bottom ash as the particle size of waste tire powder increases.

Borehole Disposal Concept: A Proposed Option for Disposal of Spent Sealed Radioactive Sources in Tanzania (보어홀 처분 개념: 탄자니아의 폐밀봉선원 처분을 위한 제안)

  • Salehe, Mikidadi;Kim, Chang-Lak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.11 no.4
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    • pp.293-301
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    • 2013
  • Borehole Disposal Concept (BDC) was initiated by the South African Nuclear Energy Corporation (NECSA) with the view to improve the radioactive waste management practices in Africa. At a time when geological disposal of radioactive waste is being considered, the need to protect ground water from possible radioactive contamination and the investigation of radionuclides migration through soil and rocks of zone of aeration into ground water has becomes very imperative. This is why the Borehole Disposal Concept (BDC) is being suggested to address the problem. The concept involves the conditioning and emplacement of disused sealed radioactive sources in an engineered facility of a relatively narrow diameter borehole (260 mm). Tanzania is operating a Radioactive Waste Management Facility where a number of spent sealed radioactive sources with long and short half lives are stored. The activity of spent sealed radioactive sources range from (1E-6 to 8.8E+3 Ci). However, the long term disposal solution is still a problem. This study therefore proposing the country to adopt the BDC, since the repository requires limited land area and has a low probability of human intrusion due to the small footprint of the borehole.

A Study on the Waste Reduction of Parcel Delivery Packaging (택배 유통포장 폐기물 감량화 방안 연구)

  • Oh, Jae Young;Jo, Hyun Jun;Suh, Sang Uk;Lee, Ga Eun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.25 no.2
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    • pp.23-29
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    • 2019
  • The volume of parcel delivery is steadily increasing with the rapid growth of the global online e-commerce market. However, a large amount of packaging materials used for these parcel delivery is finally causing environmental problems as waste. The rapid increase of these packaging waste has been making many countries to research ways to reduce the generation of distribution packaging waste. In this study, we have measured the empty space ratio for 131 packagings of parcel delivery purchased through the several domestic online stores in order to investigate the present situation in connection with the degree of excessive or overpack in korean parcel delivery packagings, so that 64 packagings were exceeded 50% in the empty space ratio. And we have suggested ways to reduce the generation of distribution packaging waste raised by e-commerce-based parcel delivery through analyzing the previous research and case studies ; one is to optimize and minimize the packaging design by safe transit test(field-to-lab test), another is to develop a reusable & returnable transport packaging and system applicable in the domestic supply chain, the other is to regulate directly with a policy.

Life Cycle Assessment(LCA) of Rubber Recycling Process in Waste Tire (폐타이어 고무 재활용 공정의 전과정평가 연구)

  • Ahn, Joong Woo;Kim, Jin Kuk
    • Resources Recycling
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    • v.27 no.1
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    • pp.74-83
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    • 2018
  • This study conducted the Life Cycle Assessment(LCA) on waste rubber recycling technology for recovering rubber product from the waste tires. Environmental impacts were assessed for the five categories of impacts: global warming, resource depletion, acidification, eutrophication, photochemical oxide production, and ozone layer depletion. When recycling 1ton of waste tire containing rubber, global warming impact was 1.77E+02 kg $CO_2-eq.$, resource depletion impact was 1.23E+00 kg Sb-eq., acidification impact was 5.92E-01 kg $SO_2-eq.$, eutrophication impact was 1.23E-01 kg $PO{_4}^{3-}-eq.$, photochemical oxide production impact was 3.42E-01 kg $C_2H_4-eq.$, and ozone layer depletion impact was 1.87E-04 kg CFC11-eq. In terms of overall environmental impacts, carbon, softener and electricity the greatest impact, so it is necessary to compare the environmental impacts of the raw materials to replace carbon and softener, and a method to reduce the filler usage in the process is needed. In addition, it is necessary to improve energy efficiency, change to low-energy sources, and apply renewable energy.

A Study on the Characteristics of the Biochar by Hydrothermal Carbonization with Food Waste (열수가압탄화법(HTC, Hydrothermal Carbonization)에 의한 음식물 폐기물 biochar의 특성 연구)

  • Cho, Woo Ri;Oh, Minah;Chung, Wonduck;Park, Seong-Kyu;Bae, Sunyoung;Lee, Jai-young
    • Journal of Soil and Groundwater Environment
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    • v.21 no.1
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    • pp.22-27
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    • 2016
  • Hydrothermal carbonization (HTC) is a carbonization method of thermochemical process at a relatively low temperature (180-250℃). It is reacted by water containing raw material. In this study, it was selected for effective disposal method of food waste because food waste in Korea has large amount water. 5 kg, 10 kg, 15 kg of food waste were reacted for 6 hours at 200℃ for selecting the optimum amount of raw material. Since the derived optimum amount, food waste was reacted for 2 hours, 4 hours and 6 hours at 200℃ and 1.5 MPa. After carbonization, it was analyzed to evaluated the properties by ultimate analysis, iodine adsorption, BET surface area and SEM. After analyzing the characteristics, it can be utilized as a basic data for applied.

A unique Vietnam's red clay-based brick reinforced with metallic wastes for γ-ray shielding purposes: Fabrication, characterization, and γ-ray attenuation properties

  • Ta Van Thuong;O.L. Tashlykov;K.A. Mahmoud
    • Nuclear Engineering and Technology
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    • v.56 no.4
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    • pp.1544-1551
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    • 2024
  • A unique brick series based on Vietnamese clay was manufactured at 114.22 MPa pressure rate for γ-ray attenuation purposes, consisting of (x) metallic waste & (90%-x) red clay mineral & 10% (hardener mixed with epoxy resin), where (x) is equal to the values 0%, 20%, 40%, 50%, and 70%. The impacts of industrial metal waste ratio in the structure and radiation protective characteristics were evaluated experimentally. The increase in metallic waste doping concentrations from 0% to 70% was associated with an increase in the manufactured brick's density (ρ) from 2.103 to 2.256 g/cm3 while the fabricated samples' porosity (Φ) decreased from 11.7 to 1.0%, respectively. Together with a rise in fabricated brick's density and a decrease in their porosities, the manufactured bricks' γ-ray attenuation capacities improved. The measured linear attenuation coefficient (μ, cm-1) was improved by 30.8%, 22.1%, 21.6%, and 19.7%, at Eγ equal to the values respectively 0.662, 1.173, 1.252, and 1.332 MeV, when the metallic waste concentration increased from 0% to 70%, respectively. The study demonstrates that manufactured bricks exhibit superior radiation shielding properties, with radiation protection efficiencies of 88.4%, 90.0%, 91.7%, 92.1%, and 92.4% for bricks with industrial metal waste contents of 0%, 20%, 40%, 50%, and 70%, respectively, at γ-ray energy (Eγ) of 1.332 MeV.

Urban Mine Resources and Metal Recycling in Korea (한국(韓國)의 도시광산(都市鑛山)(사용후제품) 자원(資源)과 금속재자원화(金屬再資源化))

  • Oh, Jae-Hyun;Kim, Joon-Soo;Moon, Suk-Min;Min, Ji-Won
    • Resources Recycling
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    • v.20 no.6
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    • pp.3-18
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    • 2011
  • In order to review the recycling status of urban mine resources in Korea, metal consumption, metal stock reserves and metal scraps and wastes such as iron scrap, end of life vehicles(ELV), E-waste were surveyed. In making up the list of the metal consumption, the statistical data from the Korea Non-Ferrous Association, the Korea Iron and Steel Association, the HS code of Korea Custom Service, the symposium and the related companies were collected. Finally, "Principle uses and recycling potential of metals in the periodic table" by T.E.Graedel was introduced. This paper suggested the key point for development of urban mine resources.

Development of Substrate and Cultural Method for the Cultivation of Pleurotus sajor-caju (느타리 버섯(Pleurotus sajor-caju) 재배를 위한 기질 및 재배방법의 개발)

  • Hong, B.S.;Kim, S.J.;Song, C.H.;Hwang, S.Y.;Yang, H.C.
    • The Korean Journal of Mycology
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    • v.20 no.4
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    • pp.354-359
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    • 1992
  • The effect of the addition of various vegetable oils on the mycelial growth was studied. Most vegetable oils were proved to be stimulative for the mycelial growth, and the best mycelial growth (12 mg/ml) was obtained with the addition of cotton seed oil. Several agricultural wastes i.e., rice straw, peanut hull, sawdust, rice hull, cocoa hull, coffee waste and beer waste were empolyed as substrates for sporophore production of p. sajor-caju. The biological efficiency(BE) for sporophore productions of rice straw and peanut hull were 36.4% and 32.6%, respectively. The highest yield of sporophore was obtained from the mixture of rice straw (50%) and beer waste (50%)(BE 109.6%) followed by peanut hull (50%) and beer waste (50%)(BE; 74.5%).

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