• Resources Recycling
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• v.21 no.3
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• pp.3-14
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• 2012

In order to review the recycling status of urban mine resources in China, recycling of ELV(End of Life Vehicles), E-waste(WEEE) and nonferrous metals were surveyed. Number of the sales volume of the new vehicles were over more than ten million and number of discharge vehicles are increasing now. However, recycling system has not been managed smoothly in China. Though usage of home appliances in urban is similar with advanced countries, there are significant differences in rural community. In the other hand, China is the country with the largest E-waste import in the world. Production and consumption of the nonferrous metals are increasing year by year in China, but recycling of metals is not enough.

• Journal of Environmental Science International
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• v.27 no.2
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• pp.109-122
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• 2018

This study was conducted to investigate the removal characteristics of heavy metals and sulfate ion from acid mine drainage by porous zeolite-slag ceramics (ZS ceramics) that was prepared by adding wood flour as pore-foaming agent while calcining the mixtures of natural zeolite and converter slag. The batch test showed that the removal efficiency of heavy metals by pellet-type porous ZS ceramics increased as the particle size of wood flour was decreased and as the weight mixing ratio of wood flour to ZS ceramics was increased. The optimal particle size and weight mixing ratio of wood flour were measured to be $75{\mu}m$ and 7~10%, respectively. The removal test with the porous ZS ceramics prepared in these optimal condition showed very high removal efficiencies: more than 98.4% for all heavy metals and 73.9% for sulfate ion. Relative to nonporous ZS ceramics, the increment of removal efficiency of heavy metals by porous ZS ceramics with $75{\mu}m$ and 10% wood flour was 5.8%, 60.5%, 36.9%, 87.7%, 10.3%, and 57.4% for Al, Cd, Cu, Mn, Pb, and Zn, respectively. The mechanism analysis of removal by the porous ZS ceramics suggested that the heavy metals and sulfate ion from acid mine drainage are eliminated by multiple reactions such as adsorption and/or ion exchange as well as precipitation and/or co-precipitation.

• Resources Recycling
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• v.24 no.3
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• pp.44-50
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• 2015

Recycling technologies would be required in consideration of increasing demand in lithium ion batteries (LIBs). In this study, the leaching behavior of Ni, Co and Mn is investigated with ammoniacal medium for spent cathode active materials, which are separated from a commercial LIB pack in hybrid electric vehicles. The leaching behavior of each metal is analyzed in the presence of reducing agent and pH buffering agent. The existence of reducing agent is necessary to increase the leaching efficiency of Ni and Co. The leaching of Mn is insignificant even with the existence of reducing agent in contrast to Ni and Co. The most conspicuous difference between acid and ammoniacal leaching would be the selective leaching behavior between Ni/Co and Mn. The ammoniacal leaching can reduce the cost of basic reagent that makes the pH of leachate higher for the precipitation of leached metals in the acid leaching.

• Journal of Digital Convergence
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• v.12 no.8
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• pp.35-47
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• 2014

With the qualitative methods for casino-related policy analysis on sense of residents, the degrees of expectation, support, adequacy, awareness, participation, contribution, and benefit which were derived from results are as follows: Firstly, from the recognition analysis on casino related policy, recognition III ranked at the top, and benefit and contribution II followed next. From the result, promotion policy on closed mine area fell short of expectations. The second phase of development project and appropriate the dead-mine development fund for promotion of substitute industry by the needs of residents. Secondly, derived from the comparative evaluation of casino-related industry, all comparison targets ; awareness of promoting policy and contribution to regional development, participation and contribution to Regional development, benefits and contribution to regional development, participation in the closed-mine area and contribution to regional balanced development, and lastly benefits and regional balanced development) are related to each other.

• Korean Institute of Interior Design Journal
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• v.20 no.5
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• pp.254-261
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• 2011

Industrial/Technological Cultural Properties are closely related to contemporary life, and have played the dominant role as a bridge between the traditional architectural buildings and contemporary architectural buildings, reflecting the overall economical, social and cultural portraits of that time. Nowadays, due to various sprawling developments and new development-oriented urban policies, only a select few Industrial/Technological Cultural Properties are being protected, the rest facing with demolition and damages. In order to better cope with such situation, Korea has officially introduced the Registered Cultural Properties System since 2001, and began acknowledging the historical values of industrial buildings as modem cultural properties. Under this circumstances, purpose of this study is to analyze main project plans of each facility in Abanoned Nordstern Mine Gelsenkirchen in the state of Nordhein-Westfalen, that have been preserved and recycled as office spaces. and to bring out the main features of the plans, so that they can be utilized to find suggestions for Industrial /Technological Cultural Properties Revitalization.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.6 s.119
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• pp.111-129
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• 2007

Industrial heritage artifacts may include the industrial products, technologies and infrastructures that have contributed to modernization beginning with the Industrial Revolution. The history of our industrial heritage spans 50 to 150 years and can be characterized by taking into account the site and the technology. This paper analyzes 13 precedents in Japan, Canada, and the United States in terms of these concerns, with focus on the reuse of abandoned mines as industrial heritage. Field surveys and interviews about each abandoned mine were used to obtain historical records and material. The results describe progress in three phases (1) recognizing phase, (2) organizing phase, and (3) maintenance management phase. A proper methodology for reuse is necessary to ensure the authenticity of the abandoned mine, particularly in the face of poor tourism-oriented approaches. As a result of analyzing the 13 cases, we determined that the following principles should be considered during the reuse process. Firstly, reuse of abandoned mines should not be compulsory but should be a spontaneous process and especially, should be carried out by inhabitants. Secondly, education and real experiences in the abandoned mine should be used to ive visitors a feeling of authenticity. Thirdly, creative remodeling methods can be used to enhance the abandoned mine's facilities and the site. Finally, historic and new functions should be the focus of the revitalization. Because this paper mainly focused on 13 precedents, there are likely more diverse cases. However, the conclusions of this report have practical value for reuse of abandoned mines and can be used in establishing methods for reusing Korean abandoned mines as industrial heritage.

• Economic and Environmental Geology
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• v.38 no.5 s.174
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• pp.535-545
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• 2005

Environmental survey from some abandoned metal mine areas was undertaken on to assess the risk of adverse health effects on human exposure to arsenic influenced by past Au-Ag mining activities. Elevated levels of As were found in tailings from the studied mine areas. This high concentration may have a impact on soils and waters around the tailing piles. In order to perform the human risk assessment, chemical analysis data of soils, rice grains and waters fur As have been used. The HQ values fer As via the rice grain and groundwater consumption were significantly higher compared with other exposure pathways in all metal mine areas. However, there were minimal soil and water dermal contact risks. The resulting Hl values of As from the Dongil, Okdong and Hwacheon mine areas were higher than 5.0, and their toxic risk due to drinking water and rice grain was strong in these mine areas. The cancer risk of being exposed to As by the rice grain route from the Dongil, Okdong and Hwacheon mine areas was $5.2\times10^{-4},\;6.0\times10^{-4}\;and\;8.1\times10^{-4}$, respectively. The As cancer risk via the exposure pathway of drinking water from these mine areas exceeded the acceptable risk of 1 in 10,000 fer regulatory purposes. Thus, the daily intakes of groundwater and rice grain by the local residents from the Dongil, Okdong and Hwacheon mine areas can pose a potential health threat if exposed by long-term arsenic exposure.

• Resources Recycling
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• v.30 no.4
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• pp.3-10
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• 2021

The field of recycling for waste electronic components, which is the typical example of an urban mine, requires the development of useful sorting techniques. In this study, a sorter based on image identification by deep learning was developed to select electronic components into four groups. They were recovered from waste printed circuit boards and should be separated to depend on the difference after treatment. The sorter consists of a workstation with GPU, camera, belt conveyor, air compressor. A small piece (less than 3.5 cm) of electronic components on the belt conveyor (belt speed: 6 cm/s) was taken and learned as teaching data. The accuracy of the image identification was 96% as kinds and 99% as groups. The optimum condition of sorting was determined by evaluating accuracies of image identification and recovery rates by blowdown when changing the operating condition such as belt speed and blowdown time of compressed air. Under the optimum condition, the accuracy of image classification in groups was 98.7%. The sorting rate was more than 70%.

• Journal of Korean Society of Water Science and Technology
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• v.26 no.6
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• pp.13-26
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• 2018

This research was conducted to elucidate the removal mechanism of heavy metals and sulfate ion from acid mine drainage(AMD) by porous zeolite-slag ceramics (ZS ceramics) packed in a column reactor system. The average removal efficiencies of heavy metals and sulfate ion from AMD by the 1:3(Z:S) porous ZS ceramics in the column reactor under the HRT condition of 24 hours were Al 97.5%, As 98.8%, Cd 86.1%, Cu 96.2%, Fe 99.7%, Mn 64.1%, Pb 97.2%, Zn 66.7%, and $SO_4{^{2-}}$ 76.0% during 121 days of operation time. The XRD analysis showed that the ferric iron from AMD could be removed by adsorption and/or ion-exchange on the porous ZS ceramics. In addition it was known that Al, As, Cu, Mn, and Zn could adsorb or coprecipitate on the surface of Fe precipitates such as schwertmannite, ferrihydrite, or goethite. The EDS analysis revealed that Al, Fe, and Mn, which were of relatively high concentration in the AMD, would be adsorbed and/or ion-exchanged on the porous ZS ceramics and also exhibited that Al, Cu, Fe, Mn, and Zn could be precipitated as the form of metal hydroxide or sulfate and adsorbed or coprecipitated on the surface of Fe precipitates. The microscopic results on the porous ZS ceramics and precipitated sludge in a column reactor system suggested that the heavy metals and sulfate ion from AMD would be eliminated by the multiple mechanisms of coprecipitation, adsorption, ion-exchange as well as precipitation.

• Journal of the Korean GEO-environmental Society
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• v.18 no.12
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• pp.25-36
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• 2017

This research was conducted to investigate the removal characteristics of heavy metals and sulfate ion from acid mine drainage (AMD) by multi-functional zeolite-slag ceramics (ZS ceramics), in which natural zeolite and converter slag were mixed and calcined at high temperature. The batch test showed that the removal efficiency of heavy metals by pellet-type ZS ceramics increased as the mixing weight ratio of converter slag to natural zeolite increased. The optimal mixing ratio of natural zeolite to converter slag for the removal of heavy metals and sulfate ion from AMD was observed to be 1:2~1:3. The adequate calcination temperature and time of ZS ceramics for the treatment of AMD were found to be $600{\sim}800^{\circ}C$ and 2 hours, respectively. The removal test of heavy metals and sulfate ion from AMD by the ZS ceramics prepared in optimal condition exhibited very high removal efficiencies close to 100% for all heavy metals (Al, As, Cd, Cu, Fe, Mn, Pb, Zn) and 77.1% for sulfate ion. The experimental results in this study revealed that the ZS ceramics could function as an effective agent for the treatment of AMD.