• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.335-343
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• 2005

The Methodology of burnup calculation with EPMA test set up in this study. The spent fuel from PWR nuclear power plant was used as specimen. This $UO_2$ fuel with $3.2\%$ of enrichment had been irradiated up to 35,000 MWd/MTU(reference data). The burnup is very important factor for nuclear fuel to estimate all fuel behaviors in reactor. To measure amounts of fission products and actinides for the burnup calcualation, chemical analysis (destructive method) has been used but it mattes long experimental time and second radio-wastes. In this study, EPMA test was available to measure amount of fission products. Neodymium is able to be detected and quantified. It can be compared with the results from chemical analysis and ORIGEN-2 code calculation. Concentration of Nd from EPMA test showed good agreement with result of ORIGEN-2 code in the same burnup.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.51-57
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• 2014

A MILD(Moderate and Intense Low oxygen Dilution) combustion, which is effective in the reduction of NOx, is considerably affected by the recirculation flow position of hot exhaust gas to the combustion furnace. A numerical analysis was accomplished to elucidate the flow characteristics in the MILD combustion incinerator for several cases with or without exhaust gas recirculation. It could be seen from the result of the present numerical study that the flow recirculation could be observed in the upper region over the vertical dividing wall for the case without exhaust gas recirculation. The optimal position of exhaust gas recirculation position was derived by the comparison of %RMS of x directional velocity for the cases with exhaust gas recirculation. The case with the exhaust gas recirculation position at the upper right of free board was the most effective with the smallest value of 57.4% RMS.

• Resources Recycling
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• v.5 no.1
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• pp.21-28
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• 1996

Burmng method tn Bnidi-ied beds 101 the effectlvr reclamation of Sunn fi,uadry sand war u~ed lather tl~an rncchan1c;ll or p~~cumatiace thodq. which are co~nmonlyu scd in foundry factoricr in Kojcu In olrlcr to rcrnuvc hlc;~ns and ha~doersi ~nm foundry sand sndaces in the fluidized bcd, the lnnsl sffccuve lcmpemture mge was h00-70W. Sulbcr slab~l~liyn dca and comliresslvc streugtli oL rccla~mcd sand recyclcd by the burning luctllod wcre lalgcr dao those of rcclalmcd a n d by lllc pncumatlc mctllod. Tile energy cost IOIt he bummy mctliod was cstimalcd al SlZ0011'on oi llie iccl;~~rncds md. The coql l~ductlon in pul.chasing nzw s;od as well as the prevenllon or cnv~conmcnl.il contamlnallnn could hc hmefitcrl hy usl~lg Ihc rec1;~rnnl~oonf liisndry siod ~ecycledb y the method rleieloped in thls sludy

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.3
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• pp.267-275
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• 2023

The cement industry has been contributing to solve the wastes problem by using various combustible wastes as alternative fuel to replace natural coal. To use more alternative fuels such as waste plastics, in the cement manufacturing process, it is necessary to stably burn alternative fuels and reduce air emissions such as NOx. This study is a case study on the multi-stage combustion calciner process, which is a technology that decreases the amount of NOx while increasing the use of alternative fuels. This study is a case study on the multi-stage combustion process, a technology that reduces the amount of harmful air emissions such as NOx while increasing the use of alternative fuels. Along results of comparing before and after applying the technology to actual cement manufacturing facilities, the amount of coal consumption decreased by 38 %, waste plastics consumption increased by 122 %, and NOx emissions decreased by 17 %. Results show that increasing the use of alternative fuels and reducing NOx emissions by multi-stage combustion is effective.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.10a
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• pp.107-123
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• 2005

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.13 no.2
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• pp.141-154
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• 2015

In general, conventional criticality analysis for spent fuel transport/storage systems have been performed based on the assumption of fresh fuel concerning the potential uncertainties from number density calculations of actinide nuclides and fission products in spent fuel. However, these evaluation methods cause financial losses due to an excessive criticality margin. In order to overcome this disadvantage, many studies have recently been conducted to design and commercialize a transportation and storage cask applied to the Burnup Credit (BUC). This study conducted an assessment to ensure criticality safety for reactor operating parameters, axial burn-up profiles and misload accident conditions, which are the factors that are likely to affect criticality safety when the BUC is applied to the dual-purpose cask under development at the KOrea RADioactive waste agency (KORAD). As a result, it was found that criticality resulting from specific power, changed substantially and relied on conditions of low enrichment and high burn-up. Considering the end effect in the case of high burn-up produced a positive-definite result. In particular, the increment of maximum effective multiplication factors due to misloading was 0.18467, confirming that misload is a factor that must be taken into account when applying the BUC. The results of this study may therefore be utilized as references in developing technologies to apply the BUC to domestic models and operational procedures or preventing any misload accidents during the process of spent fuel loading.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.237-245
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• 2011

As necessity of safety re-evaluation for spent fuel storage facility has emphasized after the Fukushima accident, accuracy improvement of heat load evaluation has become more important to acquire reliable thermal-hydraulic evaluation results. As groundwork, parametric and sensitivity analyses of various storage conditions for Kori Unit 4 spent fuel storage pool and spent fuel depletion parameters such as axial burnup effect, operation history, and specific heat are conducted using ORIGEN2 code. According to heat load evaluation and parametric sensitivity analyses, decay heat of last discharged fuel comprises maximum 80.42% of total heat load of storage facility and there is a negative correlation between effect of depletion parameters and cooling period. It is determined that specific heat is most influential parameter and operation history is secondly influential parameter. And decay heat of just discharged fuel is varied from 0.34 to 1.66 times of average value and decay heat of 1 year cooled fuel is varied from 0.55 to 1.37 times of average value in accordance with change of specific power. Namely depletion parameters can cause large variation in decay heat calculation of short-term cooled fuel. Therefore application of real operation data instead of user selection value is needed to improve evaluation accuracy. It is expected that these results could be used to improve accuracy of heat load assessment and evaluate uncertainty of calculated heat load.

• Clean Technology
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• v.27 no.3
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• pp.247-254
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• 2021

In this study, an eco-friendly combustion process of waste 2,4,6-trinitrotoluene (TNT: 2,4,6-trinitrotoluene) was developed, and fundamental data for the quantity of the organic matter in the final combustion residues is presented. Because complete combustion of TNT is not possible theoretically, the combustion process was optimized to reduce organic matter content in the combustion residue by performing measures such as heating time changes, addition of propellant material, and after treatment using a high-temp electrical furnace. From the results, it was confirmed that the organic matter content in the residue could be decreased to 7 ~ 10% with each method. The quantity of the organic matter could be minimized by optimizing the combustion conditions of the process. With only a combustion time increase, the amount of organic matter in the combustion residues was measured at about 9 wt%. The environmental friendliness of the final exhaust gas was also confirmed by real time gas component analyses. In addition, the organic contents could be reduced by a further 2 wt% by applying an additional heat treatment using an external electric furnace after the first incineration treatment. In the combustion process of propellant added waste TNT, it was found that various TNT wastes could be treated using the same eco-friendly protocols because the organic content in the residue decreased in accordance with the amount of propellant. The amount of the organic matter content produced by all these methods fulfilled the requirements under the Waste Management Act.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.1046-1049
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• 2009

최근 화석에너지 고갈 문제와 폐기물의 지속적인 발생량 증가로 인해 폐기물을 이용한 열에너지 회수가 이슈화 되고 있다. 폐기물처리를 통한 에너지 회수 공정 가운데 소각이 가장 많이 이용되고 있으나 소각시 발생하는 대기오염 물질을 처리하기 위한 설계 및 설치비용에 많이 소요 된다. 본 연구에서는 화학공정 모사기인 Aspen plus를 이용해 소각공정 및 배가스 처리 공정모사를 실시하였다. 폐기물 소각 공정으로는 1 2차 연소실과 NO2를 환원하는 SNCR공정, 산성가스(HCl, SO2)를 제거하는 SDA공정, 입자상 물질을 처리 하는 bag filter공정을 모사하였다. 공정모사 결과 실제 산업폐기물 소각로의 처리효율과 일치 하였고 이를 바탕으로 동일한 공정 및 조건하에 소각로에 투입되는 폐기물의 조성비를 달리하여 공정 모사한 결과 오염물질의 배출량을 예측할 수 있었다. 이러한 오염물질 발생량 예측은 소각장의 폐기물 투입이 일정하지 않을 경우 조업 조건의 변경에 도움 뿐만아니라 공정개선의 효과적일 것으로 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.825-828
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• 2009

고형원료인 폐기물의 감량화 및 자원화 기술 중 가장 대표적인 기술로 폐기물의 소각(incineration)기술과 가스화(gasification)용융기술을 들 수 있다. 폐기물 가스화 기술은 폐기물 내의 탄소, 수소 성분을 가스화하여 CO, $H_2$가 주성분인 합성가스(synthesis gas, syngas)로 전환하여 불연물은 용융되어 환경적으로 무해한 슬래그로 회수하는 기술이다. 폐기물 가스화 용융 시스템으로 발생된 합성가스를 재순환하여 사용하는 합성가스 재순환시스템을 통해 가스화에 필요한 열을 시스템 내에서 대체하여 사용하는 기술개발은 폐기물 가스화 용융기술의 경제성을 높일 수 있다. 본 연구에서는 고형 폐기물 가스화반응에 의해 발생되는 합성가스를 재순환하여 폐기물 가스화 용융 시스템내의 자체 에너지원으로 활용할 수 있도록 하는 합성가스 재순환 시스템 및 버너의 운전특성을 고찰하였다. 합성가스의 재순환 장치에서의 운전 압력 제어 및 유량제어를 통해서 안정적인 합성가스 재순환 성능과 재순환버너의 연소 성능을 유지할 수 있었다. 합성가스 재순환버너에 의한 16,800 $kcal/Nm^3$ 조건 및 33,600 $kcal/Nm^3$ 조건에서 운전시에도 가스화기의 운전온도는 안정적으로 유지됨에 따라 생산된 합성가스의 가스화기 보조연료 대체 및 에너지절감이 가능한 것으로 판단된다.