• Resources Recycling
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• v.11 no.6
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• pp.3-11
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• 2002

Recently, waste printed circuit board (PCB) has significantly increased in its amount due to the rapid development of electronic industries. Since several kinds of noxious materials and also valuable metals are contained in it, the waste PCB is in an urgent need of recycling for the dual purposes for the prevention of environmental pollution and recovery of valuable resources. Also, the catalyst which equipped in the exhaust pipes of automobiles to reduce emission of air pollutants contains precious met-als so that their recovery from the waste auto-catalysts is required. In this study, the recovery of valuable metals from waste PCB and auto-catalyst by arc furnace melting process has been investigated, which is known to be very stable and suitable f3r less production of pollutants due to its high operating temperature. The effect of the kind of flux on the recovery of precious metals was examined by using quicklime, converter slag, and copper slag as the flux. In addition, the influence of direct and alternating current and the applying direction of direct current has been investigated. It was observed that using converter or copper slag as a flux was more desirable for a higher efficiency in the precious metal recovery compared with quicklime. For the effect of current, application of direct current taking the bottom as a negative pole generally showed a better efficiency for the extraction of valuable metals from waste PCB, which was also observed for the case of waste auto-catalyst. The average recovery of precious metals from both wastes by arc furnace melting process was very high, which was up to in the range of 95～97%.

• Ceramist
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• v.14 no.2
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• pp.29-40
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• 2011

• Resources Recycling
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• v.28 no.5
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• pp.19-29
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• 2019

Recently, it is increasing a amount of installized solar-cell rapidly, and waste Solar cell module are generated in according to the reduction of efficiency largely. Therefore, it is concerned at the environmental problems and recycling of valuable materials, greatly. The treatment processes of end-of-life photovoltaic modules are composed the disassembly of Aluminum frames, separation of Tempered glass, removal of Ethylene Vinyl Acetate and recovery of valuable Metals. For the efficient recycling, we are considered to the treatment technology seriously. And we are proposed on the general opinions according to the developing technology, EPR (Extended Producer Responsibility) problems and promotion plans for the activation of recycling industry.

• Resources Recycling
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• v.3 no.4
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• pp.74-82
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• 1994

• Resources Recycling
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• v.29 no.2
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• pp.48-54
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• 2020

Korea, one of the manufacturing-oriented countries, consumes a large amount of metals in various industrial areas, but should depend on import of most of the metals from foreign countries. Also, global metal consumption amounts are increasing in relation to those of the world's reserve and production. Some metals are limitedly produced from only several centuries, which might lead to instability of the future supply of those metals. In addition, when such metals are hazardous, those may result in various environmental troubles with contamination. To resolve those issues, the recovery and the recycling of hazardous but valuable metals in industrial waste are desirable. However, there are overwhelming numbers of the metal types, waste generators, and amounts of wastes containing the metals, so it can be troublesome even to implement a preliminary status analysis to screen proper metals, wastes with the metals, and waste producers. Therefore, this study introduces the valuable metals for Korean industry, announced by public institutions, Also, a flow chart is suggested to facilitate a preliminary status analysis, using the domestic PRTR (Pollutant Release and Transfer Register) database, to screen proper waste producers containing some of hazardous but valuable metals such as nickel, cobalt, and manganese.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.10a
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• pp.129-130
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• 1997

1. 서론 : 반도체 제조공정중 wafer가공 공정에 사용되는 많은 양의 RO 초순수는 미세한 규소입자를 비롯하여 비교적 낮은 농도의 불순물을 포함하고 있으나, 현재 1차세정후 공정폐수로 전량 희석되어 폐기되고 있다. 반도체 제조공정에서 발생되는 이러한 세정폐수를 적절한 전처리와 분리막 처리를 통하여 유가물질인 Si 입자를 회수하고, 처리수를 재이용함으로써 환경오염의 감소 및 공업용수의 증대를 도모할 수 있다. 본 연구에서는 고분자 분리막을 이용하여 반도체 제조공정중 발생한 세정중의 유가물질인 Si를 회수하고, 용수를 재이용하기 위하여 한외여과용 평막을 제조하여 Si 함유 폐수에 대한 막성능을 평가하였으며, 또한 상용 tubular 및 hallow fiber막의 성능과도 비교하였다.

• Resources Recycling
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• v.18 no.4
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• pp.14-23
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• 2009

In terms of resources recycling and resolving waste disposal problems, it is very important to recover precious metals like Au, Ag and Pd and valuable metals like Cu, Sn and Ni from the scraps of waste electrical and electronic equipment(WEEE) that consists of detective electrical and electronic parts discarded during manufacturing electrical and electronic equipments and waste electrical and electronic parts generated during disassembling them. In general, the scraps of WEEE are composed of various metals and alloys as well as refractory oxides and plastic components. Precious and valuable metals from the scraps of WEEE can be recovered by gas-phase-volatilization, hydrometallurgical, or pyrometallurgical processes. However, the gas-phase-volatilization and hydrometallurgical processes have been suggested but not yet commercialized. At the present time, most of the commercial plants for recovering precious and valuable metals from the scraps of WEEE adopt pyrometallurgical processes. Therefore, in this paper, the technical and environmental aspects on the important pyrometallurgical processes through literature survey are reviewed, and the scale-up result of a new pyrometallurgical process for recovering the precious and valuable metals contained in the scraps of WEEE using waste copper slag is presented.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.173-177
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• 2005

리튬이온 2차전지(Lithium ion battery, LIB)는 기존에 사용되던 전지에 비해 에너지 밀도가 높고 충방전 사이클이 우수하다. 이 때문에 휴대전화와 노트북 등에 수요가 급속하게 증가하고 있으며 1995년 LIB의 생산량은 4천만 개에서 2004년에는 약 8억 개로 20배 이상 증가하였다. 이에 따라 폐LIB도 급속하게 증가하게 되어 전국적인 재활용 시스템의 확보가 필요한 실정이다. 본 연구에서는 폐LIB에 함유되어 있는 유가금속 중에서 리튬코발트옥사이드(이하 $LiCoO_2$)를 회수하기 위하여 분쇄기(orient vertical cutting mill)와 진동 Screen을 사용하여 유기분리막, 금속류(Aluminium foil, Copper foil, case 등) 그리고 전극물질(lithium cobalt oxide와 graphite 등의 혼합 분말)로 분리하였다. 전극물질에서 $LiCoO_2$와 graphite 분리를 위한 전처리 단계로서 $500^{\circ}C$ 정도의 열처리를 하여 $LiCoO_2$의 표면 성질을 변화시켜 부유선별에 의해 $LiCoO_2$와 graphite의 분리가 가능하도록 하였다. 부유선별 실험 결과 93% 이상의 순도를 가지는 $LiCoO_2$를 92% 이상 회수할 수 있었다.

• Resources Recycling
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• v.31 no.6
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• pp.81-91
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• 2022

The use of lithium-ion batteries increases significantly with the rapid spread of electronic devices and electric vehicle and thereby an increase in the amount of waste batteries is expected in the near future. Therefore, studies are continuously being conducted to recover various resources of cathode active material (Ni, Co, Mn, Li) from waste battery. In order to recover the cathode active material, black mass is generally recovered from waste battery. The general process of recovering black mass is a waste battery collection - discharge - dismantling - crushing - classification process. This study focus on the crushing/classification process among the processes. Specifically, the particle size distribution of various samples at each crushing/classification step were evaluated, and the particle shape of each particle fraction was analyzed with a microscope and SEM (Scanning Electron Microscopy)-EDS(Energy Dispersive Spectrometer). As a result, among the black mass particle, fine particle less than 74 ㎛ was the mixture of cathode and anode active material which are properly liberated from the current metals. However, coarse particle larger than 100 ㎛ was present in a form in which the current metal and active material were combined. In addition, this study developed a PBM(Population Balance Model) system that can simulate two-species mixture sample with two different crushing properties. Using developed model, the breakage parameters of two species was derived and predictive performance of breakage distribution was verified.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.04a
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• pp.59-60
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• 1994

도금공업은 주로 금속, 플라스틱 등을 소재로 하는 각종 제품의 표면을 전기적 또는 화학적 방법에 따라 석출된 비철금속질로 피복가공하여 제품의 내식, 장식적 효과 내마모성, 전기특성, 광택성, 열특성등 많은 기능을 부가하는 것을 의미한다. 이러한 도금산업은 각종 유해한 화학물질을 취급하는 관계로 도금폐수도 역시 많은 유독한 화학약품이 포함되어 있어 엄격한 규제가 요구되고 있다. 현재의 도금폐수처리는 대부분 위탁업자에 의해 이루어 지고 있으며, 위탁업자는 웅집침전법에 의한 슬러지화(함수율 80% 이하) 하여 매립되고 있는 실정이다. 이 매립물은 침출수를 방출하여 환경에 새로운 문제를 야기시키고 있다. 이러한 도금폐수 중 유가금속(Zn, Cr, Ni, Cu등)을 membrane을 이용하여 회수하고, 생성되는 물을 도금공정에 다시 투입하므로서 공해가 없는 무공해공정을 설계하는 기초자료를 얻는데 본 연구의 목적이 있다. 본 실험에서는 유가금속 중 Cr을 회수하기 위하여 Cr도금 모델폐수를 이용하여 Cr의 농도, 압력, pH등을 변화시키면서 membrane과 Cr의 상관성을 살펴보았다.