• Resources Recycling
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• v.31 no.1
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• pp.37-45
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• 2022

The development of the electrical, electronic, and telecommunication industries has increased the share of electricity in total energy consumption. With the enforcement of the Act on the Promotion of the Development, Use, and Diffusion of New and Renewable Energy in 2021, the mandatory supply ratio of new and renewable energy is expected to expand, and the amount of waste cables generated in the stage of replacing and discarding cables used in the industry is also expected to increase. The purpose of this study was to quantify the environmental burden of waste cable recycling through the life cycle assessment (LCA) method. The results showed that the higher the amount of glue contained in the waste cable, the greater was the amount of fine dust and greenhouse gases generated. In addition, by assigning weights to 10 environmental burden items, it was confirmed that the marine aquatic eco-toxicity potential (MAETP) and human toxicity potential (HTP) had the greatest environmental burden. The main causes were identified as heptane and ethanol, which were the glue contained in the waste cable and the cleaning solutions used to remove them. Therefore, it is necessary to refrain from using glue in the cable production process and reduce the environmental burden by reducing the use of waste cable cleaning solutions used in the recycling process or using alternative materials.

• Resources Recycling
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• v.3 no.2
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• pp.28-34
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• 1994

A part of used cables, such as electric and communication cables has already been recycled by using simple processing methods. However, it has been found that the main problems in recycling of the used cables are insufficient treatment of fine stranded wires and low recovery of copper by air separation process. It has been shown that copper can be effectively separated from the PE using a solvent treatment method. In the present study, the used communication wires having diameter of 0.4 mm are treated in the mixing solution of toluene and water at $86^{\circ}C$ for about 10 minutes. In the solvent treatment, the copper wires recovered have 10~15mm length, which are much longer than that of 1~2mm length copper wires recovered by air table concentration method used in current recycling plants. The process consisting of cutting, air separation and electrostatic separation would be recommendable for the treatment of mixed cables. In this investigation, fine copper powders can also efficiently be recovered from insulation materials using electrostatic separator at the conditions of 20~50RPM roller speed and 15~30KV high DC power.

• Applied Chemistry for Engineering
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• v.20 no.2
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• pp.223-226
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• 2009

In this study, we investigated the recovery of copper and synthetic fuel from the waste wire by low temperature pyrolysis which can overcome problems of the recent incineration methods. Through thermal decomposition process of waste wire, we achieved the big advantage of getting usable resources as the forms of copper and fuel with a very high value. The TG/DTA and small-scale reaction experiments were carried out to determine an optimum temperature for waste wire pyrolysis. And the pyrolysis was done at 350, 450, and $550^{\circ}C$, respectively, and heating rate of the TG/DTA was $5^{\circ}C/min$ untill $700^{\circ}C$. The result shows that the optimum temperature range for dehydrochlorination of PVC was $280{\sim}350^{\circ}C$, as a lower temperature range than $400{\sim}550^{\circ}C$ of PE and PP. Practically over 95% of copper metal and synthetic fuel, which has the 8027 kcal/kg as a calorific value, were recovered from the waste wire samples.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.375-376
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• 2005

본 연구에서는 폐전선 피복플라스틱의 재활용을 위해 마찰하전형 정전선별법을 이용하여 PVC와 rubber의 재질분리 실험을 수행하였다. 하전물질의 종류에 따른 실험결과 PVC와 Rubber의 중간 일함수 값을 갖고 있는 PP 재질이 가장 효과적이었으며, 단일 시료보다PVC와 Rubber의 혼합조건에서 더 높은 하전 값을 나타내었다. 하전특성 실험결과 공기량은 10.28wt/s 이상 그리고 상대습도는 40% 이하의 조건에서 입자의 높은 하전량을 얻을 수 있음을 확인하였다. 분리특성 실험결과 전압세기가 25kv 이상 그리고 분리대의 위치는 전기장의 중앙(0)으로부터 Negative 전극으로 -lcm 이동한 지점으로, 이때 PVC의 품위와 회수율을 각각 99.5%와 95%인 결과를 얻었다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2008.11a
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• pp.142-143
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• 2008

• Resources Recycling
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• v.22 no.5
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• pp.63-70
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• 2013

There are generated the hundreds of tons of waste electric wire per year due to replace for increase transmission capacity and/or replacement of old electric wire by Korea's national power grid and/or private industrial factories. Recently, the wire recycling technologies studied extensively in terms of effieiency by of economic aspects and environment aspects. In this paper, the patents and papers for the recycling technologies of spent electric wire were collected and analyzed. The range of search was limited in the open patents of USA (US), European Union (EP), Japan (JP), Korea (KR) and SCI journals from 1975 to 2011. Patents and journals were collected using key-words searching and filtered by filtering criteria. The trends of the patents and journals were analyzed by the years, countries, companies, and technologies.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 1993.03a
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• pp.5.3-5
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• 1993

• Journal of the Korean Applied Science and Technology
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• v.29 no.2
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• pp.268-277
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• 2012

The thermal decomposition characteristic of waste PVC wires has been studied by using TGA and fixed-bed reactor. The experimental conditions of decomposition temperatures, air flow rates and weight ratio of CaO/PVC were considered in this work. To verify the effectiveness of CaO addition to remove HCl and toxic gases generated from thermal decomposition of PVC wire, the gaseous products obtained from the thermal decomposition of PVC were analyzed by GC/MS(Gas Chromatograph and Mass Spectrometry). To investigate the effect of CaO in thermal decomposition of PVC, liquid products were also analyzed by GC/MS. And the effect of decomposition temperature, air flow rate and CaO/ PVC weight ratio on the yield of liquid, gas and residue fraction have been also studied. From this work, it was found that the removal amount of HCl generated from thermal decomposition of PVC increased with increase of CaO addition.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.202-206
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• 2003

전자파(Electromagnetic wave)는 인간이 사용하고 있는 모든 전기·전자제품에 의해 발생되는 전기장과 자기장을 의미하며 첨단과학기술의 발전과 함께 전기, 전자, 통신관련 기기의 사용이 급증함에 따라 전자파는 다른 전자기기의 심각한 전파장애와 인체에 유해한 요소로 작용하고 있다. 이러한 피해현상을 EMI(Electro Magnetic Interference)라 하며 소형화, 고집적화, 다기능화를 지향하는 현대 전기, 전자, 통신산업에 있어서 치명적인 장애요소로 대두되고 있다.(중략)

• KSBB Journal
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• v.23 no.5
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• pp.413-418
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• 2008

The production of 1,3.propanediol (1,3-PD) was investigated with Klebsiella pneumoniae DSM2026 and K. pneumoniae DSM4799 using crude glycerol obtained from biodiesel industry. Crude glycerol was used without prior purification to investigate effects of impurities in crude glycerol on 1,3-PD production. In the batch cultures, 1,3-PD production with crude glycerol was $1.1{\sim}2.5$ times higher than that with pure glycerol, indicating that crude glycerol is even a better substrate than pure glycerol for 1,3-PD fermentation. When glucose was added, 1,3-PD production and yield decreased in spite of enhanced cell growth. Furthermore, the addition of glucose was found to increase 2,3-butanediol, a by-product, significantly because of the change in metabolism in the presence of glucose. In semi-batch cultures without glucose addition, 26 g/L 1,3-PD was produced with crude glycerol, which was $2{\sim}3$ times higher than that with pure glycerol. Based on our results, it was clearly shown that crude glycerol is an effective substrate for biological 1,3-PD production, making it more feasible to produce 1,3-PD at a lower price.