• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.404-408
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• 2001

This paper focuses on the pilot-scale investigation of direct recycling of electric arc furnace (EAF) stainless steelmaking dust. The direct recycling of EAF dust is to make pellets with the mixture of the dust and the reducing agent carbon, then introduce the pellets to the EAF. The valuable metals in the dust are reduced and get into the steel as the alloying elements. Experiments simulating direct recycling in an EAF were performed using an induction furnace. But it seems difficult to reduce all metal oxides in the dust so that some metal reducing agents added in the late stage of reduction process. The valuable metals in the dust were reduced partly by carbon and partly by metal reducing agent for the economical concern. The recovery of iron, chromium and nickel from the flue dust and the amount of metal oxides in the slag were measured. The results showed that the direct recycling of EAF stainless steelmaking dust is practicable. It wes also found that direct recycling of flue EAF stainless steelmaking dusts does not affect the chemistry and quality of stainless steel produced in the EAF. It is benefit not only for the environmental protection but also for the recovery of valuable metal resources in this way.

• Journal of the Korean Home Economics Association
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• v.36 no.9
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• pp.107-125
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• 1998

Focusing on 'reuse' with a view to the importance of unused cloths, this paper investigates the aspects of consumers' recycling attitudes regarding the cause and treatment of unused clothes. This research examines the responsibilities for recycling from the standpoint of consumers, and shows their requirements and advice to consumers themselves, clothing companies as the subject of production and the government and society. Considering the pattern of clothing life, this research deals with housewives who live I Seoul, Sung-nam and Choong-ju. After several pretests, the content and format of this questionnaire is revised and added. This investigation is carred by individual interviews and reponders' filling-out, from 24 November 1997 to 5 January 1998. Among the total 1,200 questionnaires, 1,150 sheets are taken back, but only 1,132 are available to analysis. The results are as follows: Most of all, among the causes of unused clothes, the problem of clothes itself is stemmed from the more responsibility of clothing companies rather than consumers'. From production to sale the companies, considering environment and recycling, should choose proper cloth material and adequate design. And then they require the consumers' attention to laundry and conservation. More important, consumers' attitudes should be changed because consumers themselves, in fact, recognize their responsibilities for recycling of clothing, from the questionnaire. After all, the recycling of clothing should lead to reduction of unused clothes as a fundamental solution. When it comes to unused clothes, its elimination pays more money and needs specialization. Moreover, citizens should participate in the problem independently and more information on the policies of recycling should be well-informed.

• Resources Recycling
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• v.19 no.1
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• pp.49-56
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• 2010

This paper has specific objective to contribute in improving recycling ratio and settling down strategic reverse management for waste recycling. To serve in such intention, focused in investigating technological issue and suggesting executive idea. Binding thus, technological tendency and global patent, study case were analyzed mainly in fields of waste recycling system based on incentives, waste automatic collection system using RFID, waste management information system. Descriptions are consisted of tendency for technology, government policy, case analysis, discussion, conclusion.

• Resources Recycling
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• v.16 no.4
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• pp.47-60
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• 2007

Plastic supply and recycling are increasingly becoming matters of social concern. In our country, Extended Producer Responsibility(EPR) system has been adopted in 2003 to expand recycle and reuse of waste resources at producer side, and due to expansion of the EPR system, amount of the mixed plastic waste generation has been drastically increased. Plastic-plastic separation is most fundamental technique to achieve effective plastic recycling. This paper reviews recent developments in plastic-plastic separation techniques and describe future tasks. The mechanisms of each separation which contain gravity separation, electrostatic separation, flotation, and separation of automotive shredder residue are described, and commercial scale and lab-scale results are introduced.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.1
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• pp.1-6
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• 2010

Paper industry in Korea produces 14 million tons of paper and 1.3 million tons of sludge per year. Most of them has been treated by incineration, landfilling or ocean dumping. The sludge recycling to minimize the impact on the environment, so its importance is highlighted. In this study, in order to develop a new way of recycling the sludge, it was calcined and the recycled ash was tried to use as papermaking filler. Concerning the yield of calcium carbonate and the brightness and the rheology of the recycled calcination sludge, the optimum calcination conditions were found to be $600^{\circ}C$ and 12 hours. The sludge ash itself was not suitable for papermaking due to its color and low brightness. Thus the ash from the sludge was first mixed with a commercial filler and then utilized for papermaking. The effect of the increased hardness after high temperature treatment on wire abrasion was confirmed.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.40-50
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• 2018

Today, the development of industries and rapid urbanization has a profound impact on the human environment. It can be said that the environment in the craft village is most affected. The environment in these areas is severely degraded and depending on the type of production, the environment in the craft villages is different. In Phong Khe ward of Bac Ninh Province, Vietnam, there are over 204 small and large facilities of recycling and producing paper. The paper facilities produce about 200,000 tons of paper each year and the amount of paper produced is not less than 500 tons each day in Phong Khe. They are creating livelihoods for more than 6,000 workers and generating local budgets from VND- 50 billion to VND 60 billion per year. Despite this great contribution, the use of old machines and "backward" modes of production means that paper recycling has caused serious air, soil, and water pollution in the region. The specific objectives of this study were as follows: (1) provide an overview of paper production process in the Phong Khe paper craft village; (2) comprehensive literature review of the current status of water environment, atmosphere environment, soil environment and solid waste; (3) figure out about waste treatment in Phong Khe ward.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.111-116
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• 2001

Waste office paper, photocopied or laser printed, has recently increased along with office automatization. In waste office paper, toner ink is used as the printing medium in place of conventional oil ink. Since toner ink cannot be saponificated by alkali and be decolored by bleaching, different from the case of oil ink, toner remains on regenerated paper as black specks. Although cascade recycling of waste office paper is compelled at present, the demand for low-grade paper is limited. From such circumstances, a new separation process for waste office paper is demanded to achieve parallel recycling. At the first stage of separation studies, the sharpness of separation is evaluated using small separators to obtain fundamental data. In a lab-scale separator, the sample amount of one feed is generally a few grams. However, the sample amount used for brightness, ERIC, and image analysis that are generally used to evaluate the efficiency of deinking are not small for lab-scale tests of these analyses. This paper describes an investigation of a sheet preparation method by a small amount of sample under 0.5g and compares the precision of toner content determination of spectroscopic analysis and image analysis from the viewpoint of separation evaluation. The easiness and convenience of the operation using only general-purpose equipments has also been set as a principle purpose. From the viewpoint of an analysis that yields high precision with a small amount of sample in short time, the method calculating the absorption coefficient from diffuse reflectance in the visible region is the most rational method in this study.

• Resources Recycling
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• v.23 no.1
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• pp.80-85
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• 2014

Commercially operating EAF dust recycling processes were investigated by means of unit process analysis. Over 80 % of EAF recycling processes are Waelz kiln process adapted a rotary kiln as a main reactor. There are differences among these pyrometallurgical processes by plant location and timely important things such as environmental regulations. In this paper, the characteristics of each plants are analysed with the point of unit process.

• International Journal of Automotive Technology
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• v.6 no.4
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• pp.413-419
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• 2005

The United States automotive recycling infrastructure has successfully reduced the amount of automotive waste sent to landfills, especially since the introduction of shredders in the late 1950s. Shredders are necessary to process and recycle automotive hulks and other durable goods. However, this industry faces significant challenges as the automotive manufacturers are increasing the use of nonmetallic components which are difficult to recycle. Additionally, it is becoming obvious that automobiles contain hazardous materials which place heavy burdens on the environment. To address this growing concern, we propose a process planning model for automotive shredders to make tactical decisions regarding at what level to process and at what level to reprocess feed stock materials. The purpose of this paper is to test analytical models to help shredders improve the profitability and efficiency of the bulk recycling processes for end of life automobile returns. The work is motivated by an actual recycling problem that was observed at Capitol City Metals shredding facility in Indianapolis, Indiana.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.7
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• pp.72-84
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• 2001

This paper proposes a design methodology for customer, assembly and disassembly considering recycling. The disign process starts with the identification of customer needs, which are in turn converted into functional requirements. The concepts of Design for Customer(DFC), Design for Assembly(DFA), Design for Variety(DFV) and Design for Disassembly(DFD) are considered in the product design phases in order to decreas production variety and mass customization. And, a new module generation approach is developed for rearranging and clustering parts and subassemblies for disassembly and recycling. Based on the result of the module generation, a new configuration methodology is suggested to minimize the disassembly time or number of disassembly operations for recycling.