• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.05a
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• pp.196-202
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• 2005

• Clean Technology
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• v.25 no.4
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• pp.289-295
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• 2019

Though the usage of vinyls and plastics produced from fossil fuels has been increasing in the world, the eco-friendly domestic disposal or recycling of waste vinyls has to be executed because the migration or importation of waste vinyls or waste plastics are globally prohibited. Even though the eco-friendly domestic disposal or recycling of waste vinyls and waste plastics should be developed, promising eco-friendly recycling methods are few because there are extraneous substances in waste vinyls and waste plastics. Also, conventional incineration and landfill methods result in secondary contamination and then increase disposal costs. Therefore, the selective elimination of extraneous substances or other materials included in waste vinyls and waste plastics could make valuable recycling or reuse possible. In particular, the novel hybrid process in which crushing and screening are simultaneously conducted in a rotary kiln type reactor can domestically maximize the material recycling or reuse. In this study, the feasibility study for a crushing/screening hybrid process developed in Korea was performed and evaluated in case of thermal recycling (TR) and material recycling (MR). The effect of various subsidies on economic efficiency was especially evaluated by means of domestic recycling plans. The incentive revenues from waste vinyl recycling and the incineration share of waste vinyls affected the net present values and internal rate of returns of the hybrid process.

• Journal of Environmental Science International
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• v.12 no.9
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• pp.911-919
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• 2003

When the city water was heated for the optimum use of unused energy, the energy flows and losses were calculated and evaluated to improve the value of heated water systems at dwelling side. To obtain this purpose, it was simulated on heat flows under two conditions like with heat pumps or not and calculated the energy sayings. Furthermore, recycling water system was suggested for enhancing the value of heated water system. From this results, the energy flows without heat pumps showed that it was 3-4 percents of heat losses from pipes, 62 percents of energy savings from hot water uses and 34 percents of unutilized heat. When the heated water system adopt the recycling water system at dwelling side, it was improved 12 percents of total energy sayings.

• Korean Journal of Materials Research
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• v.28 no.12
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• pp.691-695
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• 2018

In this study, we investigate the recycling of aluminum-based metal matrix composites(AMCs) embedded with SiC particulates. The microstructure of the AMCs is characterized by X-ray diffraction and scanning electron microscopy. The possibility of recycling the composite scrap is attempted from the melted alloy and SiC particulates by re-melting, holding and solidification in crucibles. The recovery percentage of the matrix alloy is calculated after a number of holding times, 0, 5, 10, 15, 20, 25 and 30 minutes and for different particulate sizes and weight fractions in the Al matrix. The results show that the recovery percentage of the matrix alloy, as well as the time required for maximum recovery of the matrix, is dependent on the size and weight fraction of SiC particulates. In addition, the percentage recovery increases with particulate size but drops with the particulate fraction in the matrix. The time to reach maximum recovery falls rapidly with an increase in particulate size and fraction.

• Resources Recycling
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• v.5 no.4
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• pp.17-24
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• 1996

The computer simulation model was established to verify the applicability of smelting reduction concept to treatment of industrial wastes which becomes issue on the enviromental and recycling view point. Computer simulation model provides as following results. The increase of post combustion ratio(PCR) and heat transfer efficiency of PC energy(HTE) is effective ways to save energy. But, in order to increase PCR, recovery efficiency of post combustion energy(HTE) have to be higher than 85% HTE considering refractory life and saving energy together. Coke is most useful fuel source because it shows lowest dependence of PCR and low hydrogen content. The quality of hot metal of current process would be expected to the similar level with that of blast furnace. The utilization of scrap and Al dross can be also possible to maximize the advantages of current process which is high temperature and chemical dilution with hot metal and slag. In case of scrap, energy consumption was slightly increases because of heating up energy of scrap. Consquently, current process concept provides the possibility of intergrating recycles of industrial wastes materials such as EAF slag, coke oven dust, life terminated acidic refractory, aluminium dross and scrap by smelting reduction process.

• Resources Recycling
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• v.32 no.1
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• pp.13-20
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• 2023

The objective of this article is to summarize the commercial lithium ion battery (LIB) recycling processes in Korea and to suggest new direction for LIB recycling. A representative LIB recycler, SungEel Hitech Co. has successfully operated the LIB recycling process for over 10 years, and new recycling processes were recently proposed or developed by many recycling companies and battery manufacturers. In the new recycling processes, lithium is recovered before nickel and cobalt due to the rapid rise in lithium prices, and metal sulfate solution as final product of recycling process can be supplied to manufacturers. The main problem that the new recycling process will face is impurities, which will mainly come from end-of-life electric vehicles or new additives in LIB, although the conventional processes must be improved for mass processing.

• Journal of Power Electronics
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• v.18 no.4
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• pp.1007-1014
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• 2018

A novel dual DC-DC flyback converter with leakage-energy recycling is presented in this paper. Only an active switch is used for this converter. A pulse-width-modulation strategy is adopeted to control this switch. Two transformers are employed for the proposed converter. During the switch ON-period, the primary windings of the two transformers store energies. At the switch OFF-period, the energies stored in the primary windings of the two transformers are released to the output via the secondary windings of the two transformers. Meanwhile, the leakage energies of the two transformers can be recycled. The operating principles and steady-state analyses of the proposed converter are described in detail. A prototype circuit of the proposed converter is implemented for verifying the performances.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.1
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• pp.13-24
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• 2013

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.107-123
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• 2005

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.675-679
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• 2001

The research is to discuss the current resource recycling and recovery policy, which was enacted by Environmental Protection Administrative (EPA) in Taiwan. For the past few years, the solid waste generated in Taiwan has greatly increased about 5 % per year. In addition to the construction of landfill sites and incineration plants, 4 R techniques (Reduction, Reuse, Recycle and Recovery) were also publicized among the citizens and then promulgated to furthermore manage these increased solid waste. Although the regulations have been carried out to a great success, they still need to be revised and updated since solid waste contains varieties of different materials. Therefore, this research discusses the current regulation and makes suggestion for future regulation revision. From the results of this study, energy recovery was suggested to be emphasized in the regulation. Energy could be recovered from materials such as waste tires, and all kinds of plastic containers. Waste tires and most of the plastic containers made of hydrocarbon species, which contains great heating values, should be considered as one of the alternatives for the resource recycling.