• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.770-778
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• 2013

In this study, a liquid carbonation method was applied for producing precipitate calcium carbonate by liquid-liquid reaction. We recycled the recycling water of ready-mixed concrete, one of construction waste for use source of carbonate ion. A supernatant separated from the recycling water of ready-mixed concrete, as a result of ICP analysis of a cation, $Ca^{2+}$ was contained up to 1100 ppm. We used MEA as a $CO_2$ absorbent for the liquid carbonation. A precipitate $CaCO_3$ was produced at more than MEA 20 wt%. The precipitate $CaCO_3$ as a final product was separated and dried. The result of XRD was confirmed the generation of $CaCO_3$ to calcite structure.

• Journal of Powder Materials
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• v.23 no.4
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• pp.325-330
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• 2016

Owing to increasing demand of rare metals present in ICT products, it is necessary to promote the rare metal recycling industry from an environmental viewpoint and to prevent climate change. Despite the fact that information for toxic substances is partly indicated, a legal basis and an international standard indicating usage of rare metals is insufficient. In order to address this issue, a newly created study group of environment and climate change at the ITU (International Telecommunication Union) is doing research to develop methodologies for recycling rare metals from ICT products in an eco-friendly way. Under this group, the Republic of Korea has established two international standards related to rare metals present in ICT products. The first is 'Release of rare metal information for ICT products (ITU-T L.1100)' and the other is 'Quantitative and qualitative analysis methods for rare metals (ITU-T L.1101)'. A new proposal for recommending the provision of rare metal information through a label by manufacturers and consumer/recycling businesses has been approved recently and is supposed to be published later in 2016. Moreover, these recommendations are also being extended to IEC, ISO and other standardization organizations and a strategy to reinforce the ability for domestic standardization is being established in accordance with industrial requirements. This will promote efficient recycling of rare metals from ICT products and will help improve the domestic supply of rare metals.

• Clean Technology
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• v.21 no.4
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• pp.209-216
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• 2015

Indium-Tin-Oxide (ITO) is a material that is widely used for transparent conductive electrodes (TCEs). Indium (In), chief element of the ITO, is expected to be depleted in the near future owing to its high cost and limited reserves. To overcome the issue, ITO has to be retained by recycling redundant ITO targets after manufacturing processes. In this article, we proposed an efficient recycling way of the redundant ITO targets with investigation of the current recycling tendencies in domestic and foreign countries. As a result, it was revealed that only In is recycled from the redundant targets in domestic and Japan. As well, fabrication of TCEs is being researched with ITO nanoparticles solutions. However, since the TCEs fabricated with ITO target is superior to those with other materials, it is thought that establishment of regeneration technology of ITO itself is demanded for an efficient recycling and fabrication of ITO target.

• Resources Recycling
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• v.28 no.1
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• pp.3-14
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• 2019

Copper is used in many electronic components and construction parts due to its excellent electrical conductivity and heat transfer characteristics, and also used for pre-plating for double layer coating such as nickel, so that copper is an essential material in modern industry. Despite the expected increase of usage and importance on wiring, sensors and data equipment in the next generation industries, it is hard for securing stable copper supply and resource management resulting from the copper prices are fluctuating owing to the economic crisis in Europe, the low economic growth trend in China, and President Trump's commitment to public industrial facilities investment in U.S.. Since most of the domestic copper consumption is used by electrolytic copper cathode, we studied not only copper recycling technology which is being commercialized but also current research trend under the research stage. This study aims to examine the characteristics of each process and the areas where future recycling technology development is required.

• Resources Recycling
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• v.31 no.3
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• pp.27-39
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• 2022

The global demand for lithium-ion batteries (LIBs) has been continuously increasing since the 1990s along with the growth of the portable electronic device market. Of late, the rapid growth of the electric vehicle market has further accelerated the demand for LIBs. The demand for the LIBs is expected to surpass the supply of lithium from natural resources in the near future, posing a risk to the global lithium supply chain. Moreover, the continuous accumulation of end-of-life LIBs is expected to cause serious environmental problems. To solve these problems, recycling the spent LIBs must be viewed as a critical technological challenge that must be urgently addressed. In this study, recycling LIBs using pyrometallurgical processes and post-processes for efficient lithium recovery are briefly reviewed along with the major accomplishments in the field and current challenges.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.201-206
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• 2004

Recently, waste plastic recycling technology is transforming from Incineration system to pyrolysis gasification system which can derive the resources from environmental waste and charge no more environmental burden to nature. The present study was carried out to investigate the potential acute toxicity of derived product of pyrolysis gasifications system for recycling of waste plastic by a single oral dose in Sprague-Dawley Rats. In order to evaluate the hepatotoxic effects of derived product of pyrolysis gasification system, activities of serum transaminase were measured in rats. No related changes in survivals, clinical signs and the ratio of the liver to body weights of rats were monitored. The results showed that the single oral administration of material of pyrolysis system for recycling of waste plastic did not induce any toxic effect at orally single dose level of 0 and 100, 200, 400, 800mg/kg body weight in rats. We could not find out any significant tocxicity induced by single oral administrate of material of pyrolysis system for recycling of waste plastic.

• Nuclear Engineering and Technology
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• v.52 no.4
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• pp.689-699
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• 2020

In this work, new multi-recycling options of TRU nuclides using PWR fuel assemblies comprised of MOX and FCM (Fully Ceramic Micro Encapsulated) fuels are suggested and neutronically analyzed. These options do not use a fully recycling of TRU but a partial recycling where TRUs from MOX fuels are recycled while the ones from FCM fuels are not recycled due to their high consumption rate resulted from high burnup. In particular, additional external TRU feed in MOX fuels for each cycle was considered to significantly increase the TRU consumption rate and the finally selected option is to use external TRU and enriched uranium feed as a makeup for the heavy metal consumption in MOX fuels. This hybrid external feeding of TRU and enriched uranium in MOX fuel was shown to be very effective in significantly increasing TRU consumption rate, maintaining long cycle length, and achieving negative void reactivity worth during recycling.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.19.1-19
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• 1993

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.17.2-18
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• 1993

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.8-8
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• 1993