• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.141-148
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• 2003

한국원자력연구소에서 발생하는 액체폐기물은 환경으로의 무방출 원칙에 따라 탱크에 임시저장하면서 증발농축의 감용처리를 거쳐 고체화하거나 자연증발시설을 통해 최종 증발 처리를 한다. 폐기물의 효율적 관리를 위한 체계적인 이력관리와 문서관리 및 각종 통계자료를 도출할 수 있는 데이터베이스 시스템의 구축의 일환으로 현재 연구소에서 실시하는 액체와 고체 방사성폐기물의 처리공정상에서의 데이터 확보가 필요하다. 이를 위해 폐기물 발생현황과 처리공정별 데이터를 분석하고 공정의 흐름과정에서 확보하는 데이터를 데이터베이스에 입출력하는 응용프로그램 설계를 완료하였다. 본 연구는 연구소에서 발생하는 방사성폐기물의 발생현황과 이를 수집하여 부피축소와 감용 처리 공정을 거치는 일련의 공정과정을 분석하여 도식화한 결과와 이를 토대로 폐기물처리 업무에 맞는 데이터 입출력 프로그램을 설계 내용을 소개한다. 제한된 환경에서의 실험이 아닌 실제 처리공정상의 데이터는 서류와 인적, 물적 자원의 절약을 도모하고 방사성폐기물에 대한 추적관리 및 처리의 효율성을 향상시키며 정확하고 신속한 정보를 제공하여 방사성폐기물의 물질수지연구에 이바지 할 수 있다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.337-337
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• 2004

As one of researches for the P ＆ T purposes, a basic experiment on the recovery of actinide elements from the mixture with rare earth elements by means of electrorefining using a liquid cadmium cathode in the LiCl-KC1 eutectic melt was carried out. In order to examine the behaviors of electrodeposition of metal ions on a liquid electrode, recovery experiments of rare earth metals resulting from forming electrodeposits were performed by a galvanostatic electrolysis method at various current densities. A cyclic voltammetric technique was applied to determine reduction-oxidation potential of each metal element in the melt and to detect the changes of the multi component melt composition for on-line monitoring. Also, a collaboration study with RIAR was completed to test the preliminary feasibility on a recovery of actinide elements from the mixture with rare earth elements using a liquid cadmium cathode and actinide metals. Experimental results showed that the ratio of actinides to rare earths, 9: 0.5∼1 led to the rare earth content of about 5∼10 wt% in the deposit.

• Elastomers and Composites
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• 제23권1호
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• pp.11-17
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• 1988

The transport of chromium(VI) ion from waste water through the liquid surfactant membrane containing tri-n-octylamine as a carrier, was analyzed by a slab model and was investigated through experiments. For the experiment of membrane stability, concentrations of surfactant and liquid paraffin oil were analyzed. Extraction experiments were carried out to observe the effect of system variables, such as concentrations of carrier, and initial chromium(VI) ion in external aqueous phase at $25^{\circ}C$. It is concluded that the most stable formation of liquid membrane emulsion was obtained when surfactant concentration is above 3 wt.% and liquid paraffin oil concentration is 50 vol.%. The theoretical equation on the transport of chromium(VI) ion agreed well with the experimental results.

• 방사성폐기물학회지
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• 제22권1호
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• pp.45-54
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• 2024

Currently, off-site dose calculations for nuclear power plants are conducted using a computer program (K-DOSE 60). The program is developed based on the regulatory guidelines of the Korea Institute of Nuclear Safety (KINS), which is a domestic nuclear regulatory agency. In this study, a domestic application of the International Atomic Energy Agency (IAEA) TRS (Technical Reports Series)-472 methodology for ³H and ¹⁴C in liquid effluents was studied. The dose-evaluation methods adopted and the program configuration for dose evaluation are described based on ³H and ¹⁴C in the liquid-effluent-evaluation module of the computer program. The accuracy of the program is verified by comparing the program-calculated results with hand calculation values. Furthermore, a comparative evaluation with LADTAP II, which is a liquid-effluent-evaluation methodology developed by the U.S. NRC (Nuclear Regulatory Commission), is performed. The result confirms that the program-calculated results for the IAEA TRS-472 methodology are consistent with the hand calculation values. Meanwhile, the result of comparative evaluation with LADTAP II indicates different results depending on the methodology used.

• International Journal of Air-Conditioning and Refrigeration
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• 제12권1호
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• pp.1-9
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• 2004

The purpose of the present study is to examine the heat transport limitations in a screen mesh heat pipe for electronic cooling by theoretical analysis. Diameter of pipe was 6mm, and mesh numbers were 50, 100, 150, 200 and 250, and water was investigated as working fluid. According to the change of mesh number, wick layer, inclination and saturation temperature, the maximum heat transport limitations by capillary, entraintment, sonic and boiling were analyzed by a theoretical design method of heat pipe, including capillary pressure, pumping pressure, liquid friction coefficient in wick, vapor friction coefficient, etc. Based on the results, the capillary limitation in a small diameter of heat pipe is largely affected by mesh number and wick layer. Mesh number of 250 is desirable not to be used in pipe diameter of 6 mm, because capillary heat transport limitation decreases by the abrupt increase of liquid friction pressure due to the small liquid flow area. For the heat transport of 15 watt in 6mm diameter pipe, mesh number of 100 and one layer is an optimum wick condition, which thermal resistance is the smallest.

• Nuclear Engineering and Technology
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• 제47권7호
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• pp.859-866
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• 2015

The aim of this work is to investigate the transport mechanism of radioactive nuclides through the reverse osmosis (RO) membrane and to estimate its effectiveness for nuclide separation from radioactive liquid waste. An analytical model is developed to simulate the RO separation, and a series of experiments are set up to confirm its estimated separation behavior. The model is based on the extended Nernst-Plank equation, which handles the convective flux, diffusive flux, and electromigration flux under electroneutrality and zero electric current conditions. The distribution coefficient which arises due to ion interactions with the membrane material and the electric potential jump at the membrane interface are included as boundary conditions in solving the equation. A high Peclet approximation is adopted to simplify the calculation, but the effect of concentration polarization is included for a more accurate prediction of separation. Cobalt and cesium are specifically selected for the experiments in order to check the separation mechanism from liquid waste composed of various radioactive nuclides and nonradioactive substances, and the results are compared with the estimated cobalt and cesium rejections of the RO membrane using the model. Experimental and calculated results are shown to be in excellent agreement. The proposed model will be very useful for the prediction of separation behavior of various radioactive nuclides by the RO membrane.

• 한국토양비료학회지
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• 제30권4호
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• pp.377-383
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• 1997

제약폐기은행잎의 유기물자원화 및 식물생장억제제 개발을 위한 기초자료로 활용코자 은행잎 제약폐기물중에 함유된 식물생육 억제물질을 분리 동정하고 이들물질을 처리하여 무와 벼의 발아 및 초기생육을 검토한 결과는 다음과 같다. 1) 폐기은행잎 조추출물 10% 용액은 무 종자 발아율을 저하시키고 유묘의 생육을 억제하였으나, 1% 농도에서는 뿌리 길이가 약간 짧아졌고, 0.1% 농도는 무처리와 비슷하였다. 벼 발아율은 조추출물 10% 농도에서 31%이상 억제되었다. 2) 지베렐린 $A_3(3.3{\times}10^{-6}M)$와 조추출액(10%)을 벼 유묘와 함께 처리하면 지베렐린 $A_3(3.3{\times}10^{-6}M)$ 단독처리보다 제2엽초장이 짧았다. 3) 조추출액의 산도를 달리한 3종의 액액분리물은 (EtOAc $(pH9)A_1$, EtOAc $(pH3)A_2$, BuOH $A_3$) 모두 1% 농도에서 무 종자의 발아를 완전히 억제하였다. 4) 조추출액을 액액분리, column chromatography, HPLC에 의한 분리정제를 통하여 활성성분을 분리하고, GC/MS, NMR 분석 결과 phenol류인 catechol로 판명되었으며, 폐기은행잎 29kg으로부터 분리한 catechol량은 0.76g이었다.

• 방사성폐기물학회지
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• 제17권1호
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• pp.59-73
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• 2019

원자력발전소 운영 과정에서 발생되는 폐기물인 폐수지를 원천적으로 저감하기 위해, 새로운 폐수 정화기술을 개발하고 원전 폐수처리시스템에 가상적으로 적용하여 효용성을 평가하고자 하였다. 본 기술의 기본 원리는 폐수에 존재하는 주요 핵종이온들을 생물학적 혹은 화학적 방법을 통해 무기 결정광물로 바꾸는 방식이다. 실험실에서 폐수를 대상으로 회분식실험을 통해 핵종 제거율을 측정한 결과, 생물학적 방법은 24시간 이내에 세슘을 80% 이상 제거하였고, 화학적 방법은 95% 이상 세슘을 선택적으로 제거할 수 있었다. 그리고 원전 폐수에 존재하는 다른 주요 핵종들(Co, Ni, Fe, Cr, Mn, Eu)에 대해서도 초기 99% 이상의 높은 제거율을 보여 주었다. 우리는 APR1400 원자력발전소의 폐수처리시스템 공정에서 역삼투압(R/O)과 유기 이온교환수지 모듈 사이에 가상으로 본 기술 모듈을 설치하였다. 가상의 모듈 설치를 통한 기술적 타당성 평가를 통해, 우리는 폐수의 주요 핵종들이 90% 이상 선택적으로 제거되고 폐수지의 발생량이 대폭 감소된다는 결과를 얻을 수 있었다. 이러한 결과가 의미하는 바는 본 기술이 향후 미래에 상용화되었을 경우, 폐수지 관리 비용을 크게 감소시키고 수지 수명도 대폭 연장시킬 수 있어, 결과적으로 월성 방사성폐기물 처분시설의 저장고 포화시점을 최대한 늦출 수 있는 이점이 있다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 Proceedings of The 6th korea-china joint workshop on nuclear waste management
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• pp.329-337
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• 2005

Synroc which comprises hollandite-rich ($Ba_{1-x}Cs_{2x}\;(Al_yTi_{2-y})\;Ti_{6}O_{16},\;75wt\%$), perovskite ($Ca_{1-x}Sr_xTiO_3,\;15wt\%$) and rutile ($TiO_2,\;10wt\%$) is devised for the immobilization of Sr/Cs (1:3, wt$\%$) separated from HLW liquid. Especially, hollandite-rich Synroc with different contents of Al element is fabricated, and its mineral phase assemblage and microstructure are determined by using XRD and SEM/EDS. The durability test is carried out by using MCC-1 method, leachate is analyzed by using ICP/MS and ICP/ AES. The results indicate that hollandite-rich Synroc variants is a suitable host for Immobilization of Sr/Cs separated from HLW liquid.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 춘계 학술대회
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• pp.196-199
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• 2005

The centrifuge system in liquid radwaste system(LRS) is composed of several skids including Decanter and Separator. The decanter separates the sludge over 5mm in size within liquid radwaste by centrifuge force and drops it into 55gallon drum. The separator separates the sludge over $0.1{\mu}m$ in size within the liquid radwaste processed by Decanter by centrifuge force. The process of separating the sludge from the LRS keeps the resin in Ion Exchanger from being damaged and improves the performance of Ion Exchanger, and satisfies the decontamination factor suggested in Uljin 5,6 FSAR to safety discharge into the outer environment.