• Korean Journal of Construction Engineering and Management
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• v.8 no.4
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• pp.146-154
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• 2007

Recently, the construction wastes increase rapidly due to the revitalization of reconstruction and redevelopment, the development of new urbanization of large housing development, the expansion of social infrastructure, and so on. To solve rapid increase of construction waste, the government established "the rule on the promotion of recycling of construction waste" in December, 2003. According to the rule, construction wastes can be recycled by either processing on commission or discharger of construction waste. This study proved the validation of site recycling for construction waste as economic efficiency is analyzed through the case study of site recycling at large housing development district. Using the sensitivity analysis, factors affecting the cost of site recycling was analyzed and the break-even point for the cost of site recycling was estimated according to the factors.

• Resources Recycling
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• v.23 no.2
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• pp.26-36
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• 2014

The materials flow of copper can be analyzed into up-stream and down-stream stages based on the literature survey. Discharge and recycling stages in the down-stream have been particularly analyzed through the field survey. The waste nickel resources circulation flow may conveniently be grouped into 4 stages discharge import, collection disuse, resource recovery and product production export, the resources mainly consist of copper scrap and stainless steel scrap in 2010. The resource circulation rate of 36.83% is obtained from the above flow. Various plans are therefore, suggested in each stage to increase resource circulation rate. At discharge import stage, it is suggested to consider this kind of waste as an important resources if it is appropriately classified in detail, basides applying quota tariff to this kind of waste. At collection disuse stage, the plan of stabilizing supply and demand is suggested through the improvement of bidding system. Resources professional cycling stage crushing and grinding companies foster coexistence between large and small plans and strategies were suggested. At product production export stage, the integrated approval is suggested approval for licensing to register units as waste-treating facilities instead of exempting registration under the present condition to activate recycling industries.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.215-220
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• 2000

건조는 열풍, 스팀 및 전자기파 등의 직접 또는 간접적인 에너지를 투입하여 최종 제품, 가공, 후처리 과정에서 수분을 제거하는 필수 단위공정으로서 화공, 섬유, 식품, 제지·목재, 금속부품 및 폐기물 등에 이르기까지 모든 산업의 생산과정에서 널리 사용되고 있다. 건조공정은 국내 총에너지소비량의 1.2%('95년기준 1,413천TOE), 산업부문 에너지소비량의 2.2%를 소비하는 에너지다소비 장치의 하나이다. 실제론 산업분야 건조설비 사용업체의 에너지사용 비중 중에서 건조공정의 에너지사용 비중이 30%를 초과하고 있으나, 대부분의 건조공정의 에너지 이용효율이 50%이하로서 매우 낮은 실정이다.(중략)

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1303-1308
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• 2006

지금까지 제조업체는 생산 및 물류 시스템의 효율성 증대를 통한 제품판매 증가에만 주의를 기울여왔다. 그러나 환경에 대한 관심이 높아지고, 관련 법규가 엄격해지면서 폐기물 처리와 재활용이 기업의 생존을 위한 중요한 과제로 떠오르고 있다. 자동차 제조업계에서 역시 폐자동차 재사용 및 재활용에 대한 연구가 진행되고 있으나, 한국에서는 자동차 산업의 외형적 성장과는 달리 이에 대한 시스템 구축이 미비한 상태이다. 본 연구에서는 폐자동차의 재활용에 관한 외국의 사례를 조사하고, 폐자동차의 회수 및 해체 촉진을 위한 바람직한 정부 정책 모델을 제시하려 한다.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.41-46
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• 2006

This study was carried out to evaluate the recycled waste soils from construction site for using vegetation media. The concentrations of Cd, Pb, $Cr^{6+}$, As, Hg, Cu, Cn, organic P, TCE, and PCE were measured at recycled soil piles of an industrial waste treating company in the Metropolitan landfill area. The concentrations of polluted materials did not exceed to the standard critical levels of soil pollution in all analyzed items. The results suggested a high potential of recycling of the wastes soils for vegetation soil media. However, Cd and $Cr^{6+}$ almost reached the critical levels by the time of sampling, and it is necessary to develop a skill to lower concentrations of those pollutants. In the turfgrass test, the recycled soil did show an encouraging result as vegetation media in the early growth stage of perennial ryegrass.

• Clean Technology
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• v.29 no.1
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• pp.1-9
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• 2023

Waste explosives such as useless ammunition discharged from the military and coproduced useless explosives during the manufacturers production process have been continuously produced. These are difficult to dispose with normal waste treatment facilities due to the dangers of fire and explosion. An open burning or an open detonation at military designated disposal facilities is a classical treatment method for the dangerous explosives. The classical method raises various environmental problems by the emission of hazardous materials. An air pollution by the emission of hazardous gases such as SO_x and NO_x, soil and water contaminations by the accumulation of non-biodegradable heavy metals, are representative pollution examples. To overcome these problems, various processes for eco-friendly waste treatment methods have been developed, and some processes have already been operated in some countries. In the current report, various eco-friendly disposal processes for waste explosives or harmful materials, and their advantages and disadvantages are documented to suggest future development directions for reducing the hazardous substances by the treatment processes.

• Journal of the Korea Institute of Building Construction
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• v.19 no.4
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• pp.307-312
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• 2019

Sludge generated in the production of ready-mixed concrete is classified as waste and processed at a high cost. In particular, small and medium-sized ready-mix manufacturer are burdened with such costs, and some companies are illegally processing them. Therefore, the purpose of this study is to suggest a method for recycled remicon sludge as a concrete block composition. When the remicon sludge is simply dried, the residual chemical admixture and ettringitee contained in the sludge are present, so that the compressive strength of the concrete block and the compressive strength after freezing and thawing are largely deteriorated to meet the quality standards of the concrete shore and retaining wall block It was not possible to do. As a method for satisfying the physical performance, it was found that the remicon sludge was calcined at a high temperature of about $900^{\circ}C$. to decompose ettringite and residual chemical admixture and then used it.

• Resources Recycling
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• v.20 no.3
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• pp.3-11
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• 2011

Magnesium has been used as parts of vehicles, case materials of notebook PC and mobile phone, and its demand has been increasing recently. So until now, there has little magnesium scraps from the end of life vehicles or electronic parts, and most scraps has been generated from magnesium processing lines such as melting, die casting and machining. It is to review the present status of magnesium recycling. Here, domestic demand of magnesium, recycling amount and technologies used in domestic recycling companies were surveyed in recent years. In 2010, 8,840 tons of magnesium scraps were processed and used as raw materials for die casting products. The recycling ratio was estimated as 32.5%.

• Journal of the Korea Organic Resources Recycling Association
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• v.18 no.4
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• pp.38-44
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• 2010

Foundry sands are made up of silica and some coking agents, such as bentonite or resin, and used as templates for the production of various casting products. Foundry sands, which are repeatedly used, were finally transformed into the waste materials by heat, losing their proper functions. The used foundry sands have been treated as general wastes according to the contents of coking agents used. Silica, however, can be recycled through the proper treatment due to its physical property not to changed by heat. In this study, we have identified and investigated at the occurrence, treatment and recycling status of the used foundry sands, as well as for the regime and inhibitory factors of the recycling of them in domestic and foreign cases.

• Resources Recycling
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• v.13 no.2
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• pp.47-53
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• 2004

Waste aluminum dross is a major waste in the aluminum scrap smelters, and some metallic aluminum remains in the waste dross. In the previous study, waste aluminum dross was leached with sodium hydroxide solution to extract the remained aluminum into the solution, and aluminum hydroxide precipitate was recovered from the leached solution. A pilot plant was constructed and tested to demonstrate the developed technology. One thousand tons of waste aluminum dross could be processed, and about five hundred tons of aluminum hydroxide could be produced in the pilot plant. From the test run of the pilot plant, it was confirmed that the developed technology could be employed as a commercial scale and the produced aluminum hydroxide could be used for water treatment agent.