• 한국지반환경공학회 논문집
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• 제13권12호
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• pp.59-66
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• 2012

본 연구에서는 철도정비창 부지 내에 폐기물 및 중금속오염 구간에서 채취한 토양을 대상으로 하였다. 그리고 효율적인 정화공정 설계를 위하여 고농도 오염구간, 저농도 오염구간, 폐주물사 함유 시료를 대상으로 입도분포 및 입도 분포 오염농도 분석을 실시하였다. 하지만 폐콘크리트, 폐목재 등의 건설폐기물, 폐주물사, 소각재 등이 부지 전반에 걸쳐 매립되어 있어 일반토양 오염과 다른 양상을 보이고 있었다. 따라서 일반적인 중금속정화기술로는 오염원이 감소하지 않아 혼합된 폐기물 중에 자성을 띠는 성분을 자력선별을 적용하여 실험한 결과 중금속 오염도는 감소하는 것으로 나타났다.

• 방사선산업학회지
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• 제17권1호
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• pp.11-17
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• 2023

Waste generated during the dismantling of nuclear power plants is not only diverse in types such as metal, concrete, soil, but also in a large amount, requiring systematic and efficient management. It is very important to quickly and accurately measure radioactive contamination of wastes generated simultaneously at the decommissioning site, classify them by level, and make decisions so that they can be disposed of in accordance with related laws and regulations. In this paper, for the technical and economic aspects of recycling of radioactive metal waste generated during the dismantling of nuclear power plants, we propose a management system that can measure the radioactive contamination by shape of metal waste at the decommissioning site and automatically classify it according to the presence or absence of contamination. Accordingly, a system for collecting information on metal samples such as weight measurement and shape acquisition of metal waste, measurement of radioactive contamination and identification of nuclides, and an automatic classification system according to radioactivity measurement results were described.

• 한국환경과학회지
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• 제16권11호
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• pp.1225-1230
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• 2007

The emissions characteristics of particulate matters(PM) according to the types of wastes from industrial waste incinerator of 800 kg/hr treatment capacity were investigated. For this study, the incinerate waste are as follows; waste resin, waste wood, waste urethane, waste gunny, and waste paper. The particulate samples were collected to be emitted in stack and air pollution control(both cyclone and bag filter). In stack, the concentrations of PM were in the range of 2.61 to $26.51 mg/Sm^3$ and the major chemical species were C, Si, Cl, K, Na, Ca in all the wastes. In cyclone fly ash, the mean content of heavy metal were in the order of Fe > Zn > Pb > Cu > Mn > Cr > Ni > Cd > As > Hg and the heavy metal content of waste resin were Zn 34,197.5 mg/kg, Fe 27,587.6 mg/kg, Pb 6,055.8 mg/kg, respectively. In bag filter fly ash, the mean content of heavy metal were in the order of Zn > Pb > Fe > Cu > Mn > Cd > Cr > Ni > As > Hg and the heavy metal content of waste wood were Pb 36,405.2 mg/kg, Fe 15,762.9 mg/kg, Cu 9,989.5 mg/kg, Cd 2,230.1 mg/kg, respectively. Comparing the heavy metal content of both cyclone and bag filter, in cyclone, the Cr, Fe, Ni content were higher than in bag filter and the Cd, Cu, Hg content were lower than in bag filter.

• Nuclear Engineering and Technology
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• 제49권1호
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• pp.165-171
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• 2017

To perform the permanent disposal of metal hydroxide waste from electro-kinetic decontamination, it is necessary to secure the technology for its solidification. The integrity tests on the fabricated solidification should also meet the criteria of the Korea Radioactive Waste Agency. We carried out the solidification of metal hydroxide waste using cement solidification. The integrity tests such as the compressive strength, immersion, leach, and irradiation tests on the fabricated cement solidifications were performed. It was also confirmed that these requirements of the criteria of Korea Radioactive Waste Agency on these cement solidifications were met. The microstructures of all the cement solidifications were analyzed and discussed.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 춘계학술논문요약집
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• pp.193-194
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• 2017

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.659-663
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• 2001

In Japan, the municipal solid waste, which amounts to 50 million tons, is generated every year and most of it is incinerated. The bottom and fly ashes are disposed to the registered disposal areas under the provisions of The Waste Disposal and Public Cleaning Law. Especially, as the fly ash from the municipal waste incineration (the primary fly ash) contains heavy metals (lead, zinc, etc) and dioxins, it cannot be disposed directly without decontamination, such as moiling, cementation, chelating and dissolving processes provided in the law. However, these procedures for decontamination, except melting, are not enough for dioxins. Even in case of melting, the fly ash from the process (the secondary fly ash) contains high concentration of heavy metals (e.g., Zn; 1-20%, Pb; 1-10%). For these reasons, Metal Mining Agency of Japan (MMAJ), a governmental organization, started a four-year project to develop the treatment technologies of these fly ashes in 1999. The purpose of the project is to establish the integrated technologies to recover the valuable metals from, and to decontaminate, the primary and secondary fly-ashes in the practical scale by utilizing the existing metallurgical processes and facilities, along with the energy saving and the reduction of the environmental impact.

• 한국환경과학회지
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• 제10권2호
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• pp.153-158
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• 2001

The biosorption abilities of different parts of waste brown seaweeds and their derivatives to remove heavy metals (Cd, Zn, Pb, Cu, Fe, Ni, Mn) from waste were evaluated. The two parts of waste brown seaweeds (Undaria pinnatifida) were stems and sporophyls, and the brown seaweed derivatives were alginic fibers, active carbon added alginate(AC-alginate) and dealginate. The abilities of the sporophyls to adsorb the heavy metal ions were higher than those of stems, and those of alginates were slightly higher than those of dealginate in single ion solution. With decreasing the size of biosorbents, the velocity and the amount of adsorption increased. The abilities of alginate to remove the heavy metal ions increased in multi-ion solutions by adding active carbon to alginate. The selectivity of these biosorbents(alginate, AC-alginate) to lead ion was highest and to manganese ion was lowest.

• 방사선산업학회지
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• 제17권4호
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• pp.457-469
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• 2023

The clearance level by nuclide is announced by the Nuclear Safety and Security Commission. However, the clearance level of uranium existing in nature has not been announced, and research is needed. Therefore, the purpose of this study was to evaluate the clearance level of uranium nuclides appropriate to domestic conditions preliminary. For this purpose, this study selected major processes for recycling metal wastes and analyzed the exposure scenarios and major input factors by investigating the characteristics of each process. Then, the radiation dose to the general public and workers was evaluated according to the selected scenarios. Finally, the results of the radiation dose per unit radioactivity for each scenario were analyzed to derive the clearance level of uranium in metal waste. The results of the radiation dose assessment for both the general public and workers per unit radioactivity of uranium isotopes were shown to meet the allowable dose (individual dose of 10 µSv y^-1 and collective dose of 1 Man-Sv y^-1) regulated by the Nuclear Safety and Security Commission. The most conservative scenarios for volumetric and surface contamination were evaluated for the handling of the slag generated after the melting of the metal waste and the direct reuse of the contaminated metal waste into the building without further disposal. For each of these scenarios, the radioactivity concentration by uranium isotope was calculated, and the clearance level of uranium in metal waste was calculated through the radioactivity ratio by enrichment. The results of this study can be used as a basic data for defining the clearance level of uranium-contaminated radioactive waste.

• Nuclear Engineering and Technology
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• 제43권2호
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• pp.149-158
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• 2011

Metal waste generated from the pyroprocessing of 10 MtU of spent fuel was classified by comparing the specific activity of a relevant radionuclide with the limit value of the specific activity specified in the Korean acceptance criteria for a lowand intermediate-level waste repository. A Korean Optimized Fuel Assembly design with a 17${\times}$17 array, an initial enrichment of 4.5 weight-percent, discharge burn-up of 55 GWD/MtU, and a 10-year cooling time was considered. Initially, the mass and volume of each structural component of the assembly were calculated in detail, and a source term analysis was subsequently performed using ORIGEN-S for these components. An activation cross-section library generated by the KENO-VI/ORIGEN-S module was utilized for top-end and bottom-end pieces. As a result, an Inconel grid plate, a SUS plenum spring, a SUS guide tube subpart, SUS top-end and bottom-end pieces, and an Inconel top-end leaf spring were determined to be unacceptable for the Gyeongju low- and intermediate-level waste repository, as these waste products exceeded the acceptance criteria. In contrast, a Zircaloy grid plate and guide tube can be placed in the Gyeongju repository. Non-contaminated Zircaloy cladding occupying 76% of the metal waste was found to have a lower level of specific activity than the limit value. However, Zircaloy cladding contaminated by fission products and actinides during the decladding process of pyroprocessing was revealed to have 52 and 2 times higher specific activity levels than the limit values for alpha and $^{90}Sr$, respectively. Finally, it was found that 88.7% of the metal waste from the 17${\times}$17 Korean Optimized Fuel Assembly design should be disposed of in a deep geological repository. Therefore, it can be summarized that separation technology with a higher decontamination factor for transuranics and strontium should be developed for the efficient management of metal waste resulting from pyroprocessing.

• 자원리싸이클링
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• 제28권3호
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• pp.21-25
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• 2019

The utilization of incineration ash from municipal waste must be promoted to solve the social problem on the shortage of final disposal site. In this research, metals should be recovered to avoid the damage of the crushing machine during the utilization of incineration ash in cement industry. In fact, incineration bottom ash from municipal waste contains iron in 3-5%. Nonferrous metal and stainless steel in 1% is also included. The research and development on the physical recovery process was performed not only to remove the metals but also to recover high grade products. Metals were separated from incineration ash in Maruya Co. Ltd.. In fact, iron scrap recovered by magnetic separation can be selled. After that, mixed metal was separated from incineration ash using screen. In this research, mixed metal tried to divided copper, aluminum, brass and stainless steel using drum type magnetic separation, eddy current separation and high magnetic separation. As a result, recovered iron had an 80% for the grade. Aluminum was recovered by eddy current separation without copper and brass.