• Resources Recycling
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• v.20 no.6
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• pp.3-18
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• 2011

In order to review the recycling status of urban mine resources in Korea, metal consumption, metal stock reserves and metal scraps and wastes such as iron scrap, end of life vehicles(ELV), E-waste were surveyed. In making up the list of the metal consumption, the statistical data from the Korea Non-Ferrous Association, the Korea Iron and Steel Association, the HS code of Korea Custom Service, the symposium and the related companies were collected. Finally, "Principle uses and recycling potential of metals in the periodic table" by T.E.Graedel was introduced. This paper suggested the key point for development of urban mine resources.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2006.05a
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• pp.159-163
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• 2006

본 연구는 국제환경규제에 따라 폐자동차의 재활용율 향상을 위한 재활용 부품 우선순위를 도출하고, 폐시트 등 부품 재활용에 의한 환경성을 평가하기 위하여 폐차 해체시스템 전과정평가를 수행하였다. 연구결과 차피의 고철을 재활용 할 경우에는 지구온난화와 오존층파괴에 큰 환경이득을 얻을 수 있으나 폐시트를 폴리올 원료로 재활용할 경우에는 많은 자원의 사용으로 오히려 소각으로 인한 환경부하보다 지구온난화와 오존층파괴, 광화학산화물생성 등의 부하를 증가시키는 것으로 나타났다. 그러나 폐차의 95% 이상을 재활용 및 회수하기 위해서는 분해시간 및 시장성, 기술현황 등을 종합하여 고려하여야 하며 재활용이 곤란한 유리와 같은 다른 부품과 함께 시트의 물질재활용도 반드시 포함되어야 될 것으로 사료된다. 처리와 재활용에 따른 환경성을 비교한 결과 재활용이 필요한 부품은 시트와 유리가 가장 시급하며, 배터리, 혼합플라스틱도 재활용시 환경친화적 공정개발이 필요한 것으로 도출되었다.

• Resources Recycling
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• v.26 no.3
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• pp.17-25
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• 2017

Electric arc furnace steelmaking dust has various physicochemical properties as volatile components generated in the melting process of steel scraps in an electric arc furnace, which is captured in oxide form as fine powder by reacting with oxygen in the air. In order to efficiently recycle these electric arc furnace dust, a kinetic basic experiment and a pilot production test were carried out in parallel. As a result, it was found that the electric arc furnace dust contain a large amount of Cl and alkali components, thus it was expected that the compounds have a great adverse effect on the actual operation for the recycling. It was confirmed that the volatilization behavior was progressing actively at $1100^{\circ}C$ and the electric arc furnace dust was melted at $1250^{\circ}C$. These results are the same as a result of pilot test for the formation behavior of zinc oxide and reduced iron. These results should be useful as basic data for designing the recycling plant of the electric arc furnace dust and establishing the operating conditions.

• Resources Recycling
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• v.26 no.6
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• pp.102-107
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• 2017

To estimate the bulk density applying the composition rate for recyclable residential waste, the composition rates by volume and weight basis, the bulk densities of the separated and commingled wastes were investigated four times respectively for recyclable waste of 1,800 kg transported to waste recovery facility. The bulk densities for separated wastes were $379.0kg/m^3$ of glass bottles that is highest and metals, residues, others, cans, plastics in order. The composition rates for each separated waste were changed widely depending on either volume basis or weight basis. The composition rate by weight basis as 40.6% of the glass bottles, 32.6% of the plastics were changed to 60.2% of the plastics and 8.9% of the glass bottles in that by volume basis. The bulk density of the commingled wastes applying the composition rate by volume basis showed the similar value to the measured density than by weight basis. So it was estimated that the composition rate by volume basis was appropriate for determining the bulk density of the commingled recyclable wastes.

• Resources Recycling
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• v.13 no.2
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• pp.39-46
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• 2004

The amount of electric furnace dust has been steadily increasing due to the increase of iron scraps which are usually recycled by electric furnace melting process. To date, this electric furnace dust has usually been treated by landfilling, however, because of shortage of landfill sites and heavy metal leaching more desirable treatment schemes are urgently needed. Among several possible schemes for the proper treatment of electric furnace dust, its recycling can be said to be most desirable. In present study, the triboelectrostatic separation of zinc and zinc-containing components from electric furnace dust was attempted based on its physicochemical properties such as particle shape, size distribution, and chemical assay. The dust was found to be mixed with spherical and non-spherical shaped particles and its major component materials were $ZnFe_2$$O_4$, ZnO, Fe, Zn, and FeO. The content of zinc-containing components in the entire dust was observed to be in the range of 15～30 wt%, which reasonably justified that zinc is recyclable. The triboelectrostatic characteristic of each component material was found to be different each other since their work functions were different, and based on this characteristic zinc and zinc-containing component could be flirty separated from the dust. After selecting a proper tribo-elec-trification material, the separation features of zinc and zinc-containing component were examined by taking the distance of electrodes, electric field strength, and scavenging as the experimental variables. The highest zinc-content obtained under the optimal separating condition was found to be up to 50wt%.

• Resources Recycling
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• v.32 no.1
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• pp.50-59
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• 2023

The amount of dust generated during the dissolution of scrap in an electric arc furnace is approximately 1.5% of the scrap metal input, and it is primarily collected in a bag filter. Electric arc furnace dust primarily consists of zinc and ion. The processing of zinc starts with its conversion into pellet form by the addition of a carbon-based reducing agent(coke, anthracite) and limestone (C/S control). These pellets then undergo reduction, volatilization, and re-oxidation in rotary kiln or RHF reactor to recover crude zinc oxide (60%w/w). Next, iron is discharged from the electric arc furnace dust as a solid called Fe clinker (secondary by-product of the Fe-base). Several methods are then used to treat the Fe clinker, which vary depending on the country, including landfilling and recycling (e.g., subbase course material, aggregate for concrete, Fe-source for cement manufacturing). However, landfilling has several drawbacks, including environmental pollution due to leaching, high landfill costs, and wastage of iron resources. To improve Fe recovery in the clinker, we pulverized it into optimal -sized particles and employed specific gravity and magnetic force selection methods to isolate this metal. A carbon-based reducing agent and a binding material were added to the separated coarse powder (>10㎛) to prepare briquette clinker. A small amount (1-3%w/w) of the briquette clinker was charged with the scrap in an electric arc furnace to evaluate its feasibility as an additives (carbonaceous material, heat-generating material, and Fe source).